xref: /openbmc/linux/net/sctp/socket.c (revision dea54fba)
1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2001, 2004
3  * Copyright (c) 1999-2000 Cisco, Inc.
4  * Copyright (c) 1999-2001 Motorola, Inc.
5  * Copyright (c) 2001-2003 Intel Corp.
6  * Copyright (c) 2001-2002 Nokia, Inc.
7  * Copyright (c) 2001 La Monte H.P. Yarroll
8  *
9  * This file is part of the SCTP kernel implementation
10  *
11  * These functions interface with the sockets layer to implement the
12  * SCTP Extensions for the Sockets API.
13  *
14  * Note that the descriptions from the specification are USER level
15  * functions--this file is the functions which populate the struct proto
16  * for SCTP which is the BOTTOM of the sockets interface.
17  *
18  * This SCTP implementation is free software;
19  * you can redistribute it and/or modify it under the terms of
20  * the GNU General Public License as published by
21  * the Free Software Foundation; either version 2, or (at your option)
22  * any later version.
23  *
24  * This SCTP implementation is distributed in the hope that it
25  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
26  *                 ************************
27  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
28  * See the GNU General Public License for more details.
29  *
30  * You should have received a copy of the GNU General Public License
31  * along with GNU CC; see the file COPYING.  If not, see
32  * <http://www.gnu.org/licenses/>.
33  *
34  * Please send any bug reports or fixes you make to the
35  * email address(es):
36  *    lksctp developers <linux-sctp@vger.kernel.org>
37  *
38  * Written or modified by:
39  *    La Monte H.P. Yarroll <piggy@acm.org>
40  *    Narasimha Budihal     <narsi@refcode.org>
41  *    Karl Knutson          <karl@athena.chicago.il.us>
42  *    Jon Grimm             <jgrimm@us.ibm.com>
43  *    Xingang Guo           <xingang.guo@intel.com>
44  *    Daisy Chang           <daisyc@us.ibm.com>
45  *    Sridhar Samudrala     <samudrala@us.ibm.com>
46  *    Inaky Perez-Gonzalez  <inaky.gonzalez@intel.com>
47  *    Ardelle Fan	    <ardelle.fan@intel.com>
48  *    Ryan Layer	    <rmlayer@us.ibm.com>
49  *    Anup Pemmaiah         <pemmaiah@cc.usu.edu>
50  *    Kevin Gao             <kevin.gao@intel.com>
51  */
52 
53 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
54 
55 #include <crypto/hash.h>
56 #include <linux/types.h>
57 #include <linux/kernel.h>
58 #include <linux/wait.h>
59 #include <linux/time.h>
60 #include <linux/sched/signal.h>
61 #include <linux/ip.h>
62 #include <linux/capability.h>
63 #include <linux/fcntl.h>
64 #include <linux/poll.h>
65 #include <linux/init.h>
66 #include <linux/slab.h>
67 #include <linux/file.h>
68 #include <linux/compat.h>
69 
70 #include <net/ip.h>
71 #include <net/icmp.h>
72 #include <net/route.h>
73 #include <net/ipv6.h>
74 #include <net/inet_common.h>
75 #include <net/busy_poll.h>
76 
77 #include <linux/socket.h> /* for sa_family_t */
78 #include <linux/export.h>
79 #include <net/sock.h>
80 #include <net/sctp/sctp.h>
81 #include <net/sctp/sm.h>
82 
83 /* Forward declarations for internal helper functions. */
84 static int sctp_writeable(struct sock *sk);
85 static void sctp_wfree(struct sk_buff *skb);
86 static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p,
87 				size_t msg_len);
88 static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);
89 static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);
90 static int sctp_wait_for_accept(struct sock *sk, long timeo);
91 static void sctp_wait_for_close(struct sock *sk, long timeo);
92 static void sctp_destruct_sock(struct sock *sk);
93 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
94 					union sctp_addr *addr, int len);
95 static int sctp_bindx_add(struct sock *, struct sockaddr *, int);
96 static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);
97 static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);
98 static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);
99 static int sctp_send_asconf(struct sctp_association *asoc,
100 			    struct sctp_chunk *chunk);
101 static int sctp_do_bind(struct sock *, union sctp_addr *, int);
102 static int sctp_autobind(struct sock *sk);
103 static void sctp_sock_migrate(struct sock *, struct sock *,
104 			      struct sctp_association *, sctp_socket_type_t);
105 
106 static unsigned long sctp_memory_pressure;
107 static atomic_long_t sctp_memory_allocated;
108 struct percpu_counter sctp_sockets_allocated;
109 
110 static void sctp_enter_memory_pressure(struct sock *sk)
111 {
112 	sctp_memory_pressure = 1;
113 }
114 
115 
116 /* Get the sndbuf space available at the time on the association.  */
117 static inline int sctp_wspace(struct sctp_association *asoc)
118 {
119 	int amt;
120 
121 	if (asoc->ep->sndbuf_policy)
122 		amt = asoc->sndbuf_used;
123 	else
124 		amt = sk_wmem_alloc_get(asoc->base.sk);
125 
126 	if (amt >= asoc->base.sk->sk_sndbuf) {
127 		if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK)
128 			amt = 0;
129 		else {
130 			amt = sk_stream_wspace(asoc->base.sk);
131 			if (amt < 0)
132 				amt = 0;
133 		}
134 	} else {
135 		amt = asoc->base.sk->sk_sndbuf - amt;
136 	}
137 	return amt;
138 }
139 
140 /* Increment the used sndbuf space count of the corresponding association by
141  * the size of the outgoing data chunk.
142  * Also, set the skb destructor for sndbuf accounting later.
143  *
144  * Since it is always 1-1 between chunk and skb, and also a new skb is always
145  * allocated for chunk bundling in sctp_packet_transmit(), we can use the
146  * destructor in the data chunk skb for the purpose of the sndbuf space
147  * tracking.
148  */
149 static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
150 {
151 	struct sctp_association *asoc = chunk->asoc;
152 	struct sock *sk = asoc->base.sk;
153 
154 	/* The sndbuf space is tracked per association.  */
155 	sctp_association_hold(asoc);
156 
157 	skb_set_owner_w(chunk->skb, sk);
158 
159 	chunk->skb->destructor = sctp_wfree;
160 	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
161 	skb_shinfo(chunk->skb)->destructor_arg = chunk;
162 
163 	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
164 				sizeof(struct sk_buff) +
165 				sizeof(struct sctp_chunk);
166 
167 	refcount_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
168 	sk->sk_wmem_queued += chunk->skb->truesize;
169 	sk_mem_charge(sk, chunk->skb->truesize);
170 }
171 
172 /* Verify that this is a valid address. */
173 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
174 				   int len)
175 {
176 	struct sctp_af *af;
177 
178 	/* Verify basic sockaddr. */
179 	af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
180 	if (!af)
181 		return -EINVAL;
182 
183 	/* Is this a valid SCTP address?  */
184 	if (!af->addr_valid(addr, sctp_sk(sk), NULL))
185 		return -EINVAL;
186 
187 	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
188 		return -EINVAL;
189 
190 	return 0;
191 }
192 
193 /* Look up the association by its id.  If this is not a UDP-style
194  * socket, the ID field is always ignored.
195  */
196 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
197 {
198 	struct sctp_association *asoc = NULL;
199 
200 	/* If this is not a UDP-style socket, assoc id should be ignored. */
201 	if (!sctp_style(sk, UDP)) {
202 		/* Return NULL if the socket state is not ESTABLISHED. It
203 		 * could be a TCP-style listening socket or a socket which
204 		 * hasn't yet called connect() to establish an association.
205 		 */
206 		if (!sctp_sstate(sk, ESTABLISHED) && !sctp_sstate(sk, CLOSING))
207 			return NULL;
208 
209 		/* Get the first and the only association from the list. */
210 		if (!list_empty(&sctp_sk(sk)->ep->asocs))
211 			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
212 					  struct sctp_association, asocs);
213 		return asoc;
214 	}
215 
216 	/* Otherwise this is a UDP-style socket. */
217 	if (!id || (id == (sctp_assoc_t)-1))
218 		return NULL;
219 
220 	spin_lock_bh(&sctp_assocs_id_lock);
221 	asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
222 	spin_unlock_bh(&sctp_assocs_id_lock);
223 
224 	if (!asoc || (asoc->base.sk != sk) || asoc->base.dead)
225 		return NULL;
226 
227 	return asoc;
228 }
229 
230 /* Look up the transport from an address and an assoc id. If both address and
231  * id are specified, the associations matching the address and the id should be
232  * the same.
233  */
234 static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
235 					      struct sockaddr_storage *addr,
236 					      sctp_assoc_t id)
237 {
238 	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
239 	struct sctp_af *af = sctp_get_af_specific(addr->ss_family);
240 	union sctp_addr *laddr = (union sctp_addr *)addr;
241 	struct sctp_transport *transport;
242 
243 	if (!af || sctp_verify_addr(sk, laddr, af->sockaddr_len))
244 		return NULL;
245 
246 	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
247 					       laddr,
248 					       &transport);
249 
250 	if (!addr_asoc)
251 		return NULL;
252 
253 	id_asoc = sctp_id2assoc(sk, id);
254 	if (id_asoc && (id_asoc != addr_asoc))
255 		return NULL;
256 
257 	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sctp_sk(sk),
258 						(union sctp_addr *)addr);
259 
260 	return transport;
261 }
262 
263 /* API 3.1.2 bind() - UDP Style Syntax
264  * The syntax of bind() is,
265  *
266  *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
267  *
268  *   sd      - the socket descriptor returned by socket().
269  *   addr    - the address structure (struct sockaddr_in or struct
270  *             sockaddr_in6 [RFC 2553]),
271  *   addr_len - the size of the address structure.
272  */
273 static int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
274 {
275 	int retval = 0;
276 
277 	lock_sock(sk);
278 
279 	pr_debug("%s: sk:%p, addr:%p, addr_len:%d\n", __func__, sk,
280 		 addr, addr_len);
281 
282 	/* Disallow binding twice. */
283 	if (!sctp_sk(sk)->ep->base.bind_addr.port)
284 		retval = sctp_do_bind(sk, (union sctp_addr *)addr,
285 				      addr_len);
286 	else
287 		retval = -EINVAL;
288 
289 	release_sock(sk);
290 
291 	return retval;
292 }
293 
294 static long sctp_get_port_local(struct sock *, union sctp_addr *);
295 
296 /* Verify this is a valid sockaddr. */
297 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
298 					union sctp_addr *addr, int len)
299 {
300 	struct sctp_af *af;
301 
302 	/* Check minimum size.  */
303 	if (len < sizeof (struct sockaddr))
304 		return NULL;
305 
306 	/* V4 mapped address are really of AF_INET family */
307 	if (addr->sa.sa_family == AF_INET6 &&
308 	    ipv6_addr_v4mapped(&addr->v6.sin6_addr)) {
309 		if (!opt->pf->af_supported(AF_INET, opt))
310 			return NULL;
311 	} else {
312 		/* Does this PF support this AF? */
313 		if (!opt->pf->af_supported(addr->sa.sa_family, opt))
314 			return NULL;
315 	}
316 
317 	/* If we get this far, af is valid. */
318 	af = sctp_get_af_specific(addr->sa.sa_family);
319 
320 	if (len < af->sockaddr_len)
321 		return NULL;
322 
323 	return af;
324 }
325 
326 /* Bind a local address either to an endpoint or to an association.  */
327 static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
328 {
329 	struct net *net = sock_net(sk);
330 	struct sctp_sock *sp = sctp_sk(sk);
331 	struct sctp_endpoint *ep = sp->ep;
332 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
333 	struct sctp_af *af;
334 	unsigned short snum;
335 	int ret = 0;
336 
337 	/* Common sockaddr verification. */
338 	af = sctp_sockaddr_af(sp, addr, len);
339 	if (!af) {
340 		pr_debug("%s: sk:%p, newaddr:%p, len:%d EINVAL\n",
341 			 __func__, sk, addr, len);
342 		return -EINVAL;
343 	}
344 
345 	snum = ntohs(addr->v4.sin_port);
346 
347 	pr_debug("%s: sk:%p, new addr:%pISc, port:%d, new port:%d, len:%d\n",
348 		 __func__, sk, &addr->sa, bp->port, snum, len);
349 
350 	/* PF specific bind() address verification. */
351 	if (!sp->pf->bind_verify(sp, addr))
352 		return -EADDRNOTAVAIL;
353 
354 	/* We must either be unbound, or bind to the same port.
355 	 * It's OK to allow 0 ports if we are already bound.
356 	 * We'll just inhert an already bound port in this case
357 	 */
358 	if (bp->port) {
359 		if (!snum)
360 			snum = bp->port;
361 		else if (snum != bp->port) {
362 			pr_debug("%s: new port %d doesn't match existing port "
363 				 "%d\n", __func__, snum, bp->port);
364 			return -EINVAL;
365 		}
366 	}
367 
368 	if (snum && snum < inet_prot_sock(net) &&
369 	    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
370 		return -EACCES;
371 
372 	/* See if the address matches any of the addresses we may have
373 	 * already bound before checking against other endpoints.
374 	 */
375 	if (sctp_bind_addr_match(bp, addr, sp))
376 		return -EINVAL;
377 
378 	/* Make sure we are allowed to bind here.
379 	 * The function sctp_get_port_local() does duplicate address
380 	 * detection.
381 	 */
382 	addr->v4.sin_port = htons(snum);
383 	if ((ret = sctp_get_port_local(sk, addr))) {
384 		return -EADDRINUSE;
385 	}
386 
387 	/* Refresh ephemeral port.  */
388 	if (!bp->port)
389 		bp->port = inet_sk(sk)->inet_num;
390 
391 	/* Add the address to the bind address list.
392 	 * Use GFP_ATOMIC since BHs will be disabled.
393 	 */
394 	ret = sctp_add_bind_addr(bp, addr, af->sockaddr_len,
395 				 SCTP_ADDR_SRC, GFP_ATOMIC);
396 
397 	/* Copy back into socket for getsockname() use. */
398 	if (!ret) {
399 		inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num);
400 		sp->pf->to_sk_saddr(addr, sk);
401 	}
402 
403 	return ret;
404 }
405 
406  /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
407  *
408  * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
409  * at any one time.  If a sender, after sending an ASCONF chunk, decides
410  * it needs to transfer another ASCONF Chunk, it MUST wait until the
411  * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
412  * subsequent ASCONF. Note this restriction binds each side, so at any
413  * time two ASCONF may be in-transit on any given association (one sent
414  * from each endpoint).
415  */
416 static int sctp_send_asconf(struct sctp_association *asoc,
417 			    struct sctp_chunk *chunk)
418 {
419 	struct net 	*net = sock_net(asoc->base.sk);
420 	int		retval = 0;
421 
422 	/* If there is an outstanding ASCONF chunk, queue it for later
423 	 * transmission.
424 	 */
425 	if (asoc->addip_last_asconf) {
426 		list_add_tail(&chunk->list, &asoc->addip_chunk_list);
427 		goto out;
428 	}
429 
430 	/* Hold the chunk until an ASCONF_ACK is received. */
431 	sctp_chunk_hold(chunk);
432 	retval = sctp_primitive_ASCONF(net, asoc, chunk);
433 	if (retval)
434 		sctp_chunk_free(chunk);
435 	else
436 		asoc->addip_last_asconf = chunk;
437 
438 out:
439 	return retval;
440 }
441 
442 /* Add a list of addresses as bind addresses to local endpoint or
443  * association.
444  *
445  * Basically run through each address specified in the addrs/addrcnt
446  * array/length pair, determine if it is IPv6 or IPv4 and call
447  * sctp_do_bind() on it.
448  *
449  * If any of them fails, then the operation will be reversed and the
450  * ones that were added will be removed.
451  *
452  * Only sctp_setsockopt_bindx() is supposed to call this function.
453  */
454 static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
455 {
456 	int cnt;
457 	int retval = 0;
458 	void *addr_buf;
459 	struct sockaddr *sa_addr;
460 	struct sctp_af *af;
461 
462 	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n", __func__, sk,
463 		 addrs, addrcnt);
464 
465 	addr_buf = addrs;
466 	for (cnt = 0; cnt < addrcnt; cnt++) {
467 		/* The list may contain either IPv4 or IPv6 address;
468 		 * determine the address length for walking thru the list.
469 		 */
470 		sa_addr = addr_buf;
471 		af = sctp_get_af_specific(sa_addr->sa_family);
472 		if (!af) {
473 			retval = -EINVAL;
474 			goto err_bindx_add;
475 		}
476 
477 		retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
478 				      af->sockaddr_len);
479 
480 		addr_buf += af->sockaddr_len;
481 
482 err_bindx_add:
483 		if (retval < 0) {
484 			/* Failed. Cleanup the ones that have been added */
485 			if (cnt > 0)
486 				sctp_bindx_rem(sk, addrs, cnt);
487 			return retval;
488 		}
489 	}
490 
491 	return retval;
492 }
493 
494 /* Send an ASCONF chunk with Add IP address parameters to all the peers of the
495  * associations that are part of the endpoint indicating that a list of local
496  * addresses are added to the endpoint.
497  *
498  * If any of the addresses is already in the bind address list of the
499  * association, we do not send the chunk for that association.  But it will not
500  * affect other associations.
501  *
502  * Only sctp_setsockopt_bindx() is supposed to call this function.
503  */
504 static int sctp_send_asconf_add_ip(struct sock		*sk,
505 				   struct sockaddr	*addrs,
506 				   int 			addrcnt)
507 {
508 	struct net *net = sock_net(sk);
509 	struct sctp_sock		*sp;
510 	struct sctp_endpoint		*ep;
511 	struct sctp_association		*asoc;
512 	struct sctp_bind_addr		*bp;
513 	struct sctp_chunk		*chunk;
514 	struct sctp_sockaddr_entry	*laddr;
515 	union sctp_addr			*addr;
516 	union sctp_addr			saveaddr;
517 	void				*addr_buf;
518 	struct sctp_af			*af;
519 	struct list_head		*p;
520 	int 				i;
521 	int 				retval = 0;
522 
523 	if (!net->sctp.addip_enable)
524 		return retval;
525 
526 	sp = sctp_sk(sk);
527 	ep = sp->ep;
528 
529 	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
530 		 __func__, sk, addrs, addrcnt);
531 
532 	list_for_each_entry(asoc, &ep->asocs, asocs) {
533 		if (!asoc->peer.asconf_capable)
534 			continue;
535 
536 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
537 			continue;
538 
539 		if (!sctp_state(asoc, ESTABLISHED))
540 			continue;
541 
542 		/* Check if any address in the packed array of addresses is
543 		 * in the bind address list of the association. If so,
544 		 * do not send the asconf chunk to its peer, but continue with
545 		 * other associations.
546 		 */
547 		addr_buf = addrs;
548 		for (i = 0; i < addrcnt; i++) {
549 			addr = addr_buf;
550 			af = sctp_get_af_specific(addr->v4.sin_family);
551 			if (!af) {
552 				retval = -EINVAL;
553 				goto out;
554 			}
555 
556 			if (sctp_assoc_lookup_laddr(asoc, addr))
557 				break;
558 
559 			addr_buf += af->sockaddr_len;
560 		}
561 		if (i < addrcnt)
562 			continue;
563 
564 		/* Use the first valid address in bind addr list of
565 		 * association as Address Parameter of ASCONF CHUNK.
566 		 */
567 		bp = &asoc->base.bind_addr;
568 		p = bp->address_list.next;
569 		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
570 		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
571 						   addrcnt, SCTP_PARAM_ADD_IP);
572 		if (!chunk) {
573 			retval = -ENOMEM;
574 			goto out;
575 		}
576 
577 		/* Add the new addresses to the bind address list with
578 		 * use_as_src set to 0.
579 		 */
580 		addr_buf = addrs;
581 		for (i = 0; i < addrcnt; i++) {
582 			addr = addr_buf;
583 			af = sctp_get_af_specific(addr->v4.sin_family);
584 			memcpy(&saveaddr, addr, af->sockaddr_len);
585 			retval = sctp_add_bind_addr(bp, &saveaddr,
586 						    sizeof(saveaddr),
587 						    SCTP_ADDR_NEW, GFP_ATOMIC);
588 			addr_buf += af->sockaddr_len;
589 		}
590 		if (asoc->src_out_of_asoc_ok) {
591 			struct sctp_transport *trans;
592 
593 			list_for_each_entry(trans,
594 			    &asoc->peer.transport_addr_list, transports) {
595 				/* Clear the source and route cache */
596 				sctp_transport_dst_release(trans);
597 				trans->cwnd = min(4*asoc->pathmtu, max_t(__u32,
598 				    2*asoc->pathmtu, 4380));
599 				trans->ssthresh = asoc->peer.i.a_rwnd;
600 				trans->rto = asoc->rto_initial;
601 				sctp_max_rto(asoc, trans);
602 				trans->rtt = trans->srtt = trans->rttvar = 0;
603 				sctp_transport_route(trans, NULL,
604 				    sctp_sk(asoc->base.sk));
605 			}
606 		}
607 		retval = sctp_send_asconf(asoc, chunk);
608 	}
609 
610 out:
611 	return retval;
612 }
613 
614 /* Remove a list of addresses from bind addresses list.  Do not remove the
615  * last address.
616  *
617  * Basically run through each address specified in the addrs/addrcnt
618  * array/length pair, determine if it is IPv6 or IPv4 and call
619  * sctp_del_bind() on it.
620  *
621  * If any of them fails, then the operation will be reversed and the
622  * ones that were removed will be added back.
623  *
624  * At least one address has to be left; if only one address is
625  * available, the operation will return -EBUSY.
626  *
627  * Only sctp_setsockopt_bindx() is supposed to call this function.
628  */
629 static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
630 {
631 	struct sctp_sock *sp = sctp_sk(sk);
632 	struct sctp_endpoint *ep = sp->ep;
633 	int cnt;
634 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
635 	int retval = 0;
636 	void *addr_buf;
637 	union sctp_addr *sa_addr;
638 	struct sctp_af *af;
639 
640 	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
641 		 __func__, sk, addrs, addrcnt);
642 
643 	addr_buf = addrs;
644 	for (cnt = 0; cnt < addrcnt; cnt++) {
645 		/* If the bind address list is empty or if there is only one
646 		 * bind address, there is nothing more to be removed (we need
647 		 * at least one address here).
648 		 */
649 		if (list_empty(&bp->address_list) ||
650 		    (sctp_list_single_entry(&bp->address_list))) {
651 			retval = -EBUSY;
652 			goto err_bindx_rem;
653 		}
654 
655 		sa_addr = addr_buf;
656 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
657 		if (!af) {
658 			retval = -EINVAL;
659 			goto err_bindx_rem;
660 		}
661 
662 		if (!af->addr_valid(sa_addr, sp, NULL)) {
663 			retval = -EADDRNOTAVAIL;
664 			goto err_bindx_rem;
665 		}
666 
667 		if (sa_addr->v4.sin_port &&
668 		    sa_addr->v4.sin_port != htons(bp->port)) {
669 			retval = -EINVAL;
670 			goto err_bindx_rem;
671 		}
672 
673 		if (!sa_addr->v4.sin_port)
674 			sa_addr->v4.sin_port = htons(bp->port);
675 
676 		/* FIXME - There is probably a need to check if sk->sk_saddr and
677 		 * sk->sk_rcv_addr are currently set to one of the addresses to
678 		 * be removed. This is something which needs to be looked into
679 		 * when we are fixing the outstanding issues with multi-homing
680 		 * socket routing and failover schemes. Refer to comments in
681 		 * sctp_do_bind(). -daisy
682 		 */
683 		retval = sctp_del_bind_addr(bp, sa_addr);
684 
685 		addr_buf += af->sockaddr_len;
686 err_bindx_rem:
687 		if (retval < 0) {
688 			/* Failed. Add the ones that has been removed back */
689 			if (cnt > 0)
690 				sctp_bindx_add(sk, addrs, cnt);
691 			return retval;
692 		}
693 	}
694 
695 	return retval;
696 }
697 
698 /* Send an ASCONF chunk with Delete IP address parameters to all the peers of
699  * the associations that are part of the endpoint indicating that a list of
700  * local addresses are removed from the endpoint.
701  *
702  * If any of the addresses is already in the bind address list of the
703  * association, we do not send the chunk for that association.  But it will not
704  * affect other associations.
705  *
706  * Only sctp_setsockopt_bindx() is supposed to call this function.
707  */
708 static int sctp_send_asconf_del_ip(struct sock		*sk,
709 				   struct sockaddr	*addrs,
710 				   int			addrcnt)
711 {
712 	struct net *net = sock_net(sk);
713 	struct sctp_sock	*sp;
714 	struct sctp_endpoint	*ep;
715 	struct sctp_association	*asoc;
716 	struct sctp_transport	*transport;
717 	struct sctp_bind_addr	*bp;
718 	struct sctp_chunk	*chunk;
719 	union sctp_addr		*laddr;
720 	void			*addr_buf;
721 	struct sctp_af		*af;
722 	struct sctp_sockaddr_entry *saddr;
723 	int 			i;
724 	int 			retval = 0;
725 	int			stored = 0;
726 
727 	chunk = NULL;
728 	if (!net->sctp.addip_enable)
729 		return retval;
730 
731 	sp = sctp_sk(sk);
732 	ep = sp->ep;
733 
734 	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
735 		 __func__, sk, addrs, addrcnt);
736 
737 	list_for_each_entry(asoc, &ep->asocs, asocs) {
738 
739 		if (!asoc->peer.asconf_capable)
740 			continue;
741 
742 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
743 			continue;
744 
745 		if (!sctp_state(asoc, ESTABLISHED))
746 			continue;
747 
748 		/* Check if any address in the packed array of addresses is
749 		 * not present in the bind address list of the association.
750 		 * If so, do not send the asconf chunk to its peer, but
751 		 * continue with other associations.
752 		 */
753 		addr_buf = addrs;
754 		for (i = 0; i < addrcnt; i++) {
755 			laddr = addr_buf;
756 			af = sctp_get_af_specific(laddr->v4.sin_family);
757 			if (!af) {
758 				retval = -EINVAL;
759 				goto out;
760 			}
761 
762 			if (!sctp_assoc_lookup_laddr(asoc, laddr))
763 				break;
764 
765 			addr_buf += af->sockaddr_len;
766 		}
767 		if (i < addrcnt)
768 			continue;
769 
770 		/* Find one address in the association's bind address list
771 		 * that is not in the packed array of addresses. This is to
772 		 * make sure that we do not delete all the addresses in the
773 		 * association.
774 		 */
775 		bp = &asoc->base.bind_addr;
776 		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
777 					       addrcnt, sp);
778 		if ((laddr == NULL) && (addrcnt == 1)) {
779 			if (asoc->asconf_addr_del_pending)
780 				continue;
781 			asoc->asconf_addr_del_pending =
782 			    kzalloc(sizeof(union sctp_addr), GFP_ATOMIC);
783 			if (asoc->asconf_addr_del_pending == NULL) {
784 				retval = -ENOMEM;
785 				goto out;
786 			}
787 			asoc->asconf_addr_del_pending->sa.sa_family =
788 				    addrs->sa_family;
789 			asoc->asconf_addr_del_pending->v4.sin_port =
790 				    htons(bp->port);
791 			if (addrs->sa_family == AF_INET) {
792 				struct sockaddr_in *sin;
793 
794 				sin = (struct sockaddr_in *)addrs;
795 				asoc->asconf_addr_del_pending->v4.sin_addr.s_addr = sin->sin_addr.s_addr;
796 			} else if (addrs->sa_family == AF_INET6) {
797 				struct sockaddr_in6 *sin6;
798 
799 				sin6 = (struct sockaddr_in6 *)addrs;
800 				asoc->asconf_addr_del_pending->v6.sin6_addr = sin6->sin6_addr;
801 			}
802 
803 			pr_debug("%s: keep the last address asoc:%p %pISc at %p\n",
804 				 __func__, asoc, &asoc->asconf_addr_del_pending->sa,
805 				 asoc->asconf_addr_del_pending);
806 
807 			asoc->src_out_of_asoc_ok = 1;
808 			stored = 1;
809 			goto skip_mkasconf;
810 		}
811 
812 		if (laddr == NULL)
813 			return -EINVAL;
814 
815 		/* We do not need RCU protection throughout this loop
816 		 * because this is done under a socket lock from the
817 		 * setsockopt call.
818 		 */
819 		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
820 						   SCTP_PARAM_DEL_IP);
821 		if (!chunk) {
822 			retval = -ENOMEM;
823 			goto out;
824 		}
825 
826 skip_mkasconf:
827 		/* Reset use_as_src flag for the addresses in the bind address
828 		 * list that are to be deleted.
829 		 */
830 		addr_buf = addrs;
831 		for (i = 0; i < addrcnt; i++) {
832 			laddr = addr_buf;
833 			af = sctp_get_af_specific(laddr->v4.sin_family);
834 			list_for_each_entry(saddr, &bp->address_list, list) {
835 				if (sctp_cmp_addr_exact(&saddr->a, laddr))
836 					saddr->state = SCTP_ADDR_DEL;
837 			}
838 			addr_buf += af->sockaddr_len;
839 		}
840 
841 		/* Update the route and saddr entries for all the transports
842 		 * as some of the addresses in the bind address list are
843 		 * about to be deleted and cannot be used as source addresses.
844 		 */
845 		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
846 					transports) {
847 			sctp_transport_dst_release(transport);
848 			sctp_transport_route(transport, NULL,
849 					     sctp_sk(asoc->base.sk));
850 		}
851 
852 		if (stored)
853 			/* We don't need to transmit ASCONF */
854 			continue;
855 		retval = sctp_send_asconf(asoc, chunk);
856 	}
857 out:
858 	return retval;
859 }
860 
861 /* set addr events to assocs in the endpoint.  ep and addr_wq must be locked */
862 int sctp_asconf_mgmt(struct sctp_sock *sp, struct sctp_sockaddr_entry *addrw)
863 {
864 	struct sock *sk = sctp_opt2sk(sp);
865 	union sctp_addr *addr;
866 	struct sctp_af *af;
867 
868 	/* It is safe to write port space in caller. */
869 	addr = &addrw->a;
870 	addr->v4.sin_port = htons(sp->ep->base.bind_addr.port);
871 	af = sctp_get_af_specific(addr->sa.sa_family);
872 	if (!af)
873 		return -EINVAL;
874 	if (sctp_verify_addr(sk, addr, af->sockaddr_len))
875 		return -EINVAL;
876 
877 	if (addrw->state == SCTP_ADDR_NEW)
878 		return sctp_send_asconf_add_ip(sk, (struct sockaddr *)addr, 1);
879 	else
880 		return sctp_send_asconf_del_ip(sk, (struct sockaddr *)addr, 1);
881 }
882 
883 /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
884  *
885  * API 8.1
886  * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt,
887  *                int flags);
888  *
889  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
890  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
891  * or IPv6 addresses.
892  *
893  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
894  * Section 3.1.2 for this usage.
895  *
896  * addrs is a pointer to an array of one or more socket addresses. Each
897  * address is contained in its appropriate structure (i.e. struct
898  * sockaddr_in or struct sockaddr_in6) the family of the address type
899  * must be used to distinguish the address length (note that this
900  * representation is termed a "packed array" of addresses). The caller
901  * specifies the number of addresses in the array with addrcnt.
902  *
903  * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns
904  * -1, and sets errno to the appropriate error code.
905  *
906  * For SCTP, the port given in each socket address must be the same, or
907  * sctp_bindx() will fail, setting errno to EINVAL.
908  *
909  * The flags parameter is formed from the bitwise OR of zero or more of
910  * the following currently defined flags:
911  *
912  * SCTP_BINDX_ADD_ADDR
913  *
914  * SCTP_BINDX_REM_ADDR
915  *
916  * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
917  * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given
918  * addresses from the association. The two flags are mutually exclusive;
919  * if both are given, sctp_bindx() will fail with EINVAL. A caller may
920  * not remove all addresses from an association; sctp_bindx() will
921  * reject such an attempt with EINVAL.
922  *
923  * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
924  * additional addresses with an endpoint after calling bind().  Or use
925  * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
926  * socket is associated with so that no new association accepted will be
927  * associated with those addresses. If the endpoint supports dynamic
928  * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
929  * endpoint to send the appropriate message to the peer to change the
930  * peers address lists.
931  *
932  * Adding and removing addresses from a connected association is
933  * optional functionality. Implementations that do not support this
934  * functionality should return EOPNOTSUPP.
935  *
936  * Basically do nothing but copying the addresses from user to kernel
937  * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
938  * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
939  * from userspace.
940  *
941  * We don't use copy_from_user() for optimization: we first do the
942  * sanity checks (buffer size -fast- and access check-healthy
943  * pointer); if all of those succeed, then we can alloc the memory
944  * (expensive operation) needed to copy the data to kernel. Then we do
945  * the copying without checking the user space area
946  * (__copy_from_user()).
947  *
948  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
949  * it.
950  *
951  * sk        The sk of the socket
952  * addrs     The pointer to the addresses in user land
953  * addrssize Size of the addrs buffer
954  * op        Operation to perform (add or remove, see the flags of
955  *           sctp_bindx)
956  *
957  * Returns 0 if ok, <0 errno code on error.
958  */
959 static int sctp_setsockopt_bindx(struct sock *sk,
960 				 struct sockaddr __user *addrs,
961 				 int addrs_size, int op)
962 {
963 	struct sockaddr *kaddrs;
964 	int err;
965 	int addrcnt = 0;
966 	int walk_size = 0;
967 	struct sockaddr *sa_addr;
968 	void *addr_buf;
969 	struct sctp_af *af;
970 
971 	pr_debug("%s: sk:%p addrs:%p addrs_size:%d opt:%d\n",
972 		 __func__, sk, addrs, addrs_size, op);
973 
974 	if (unlikely(addrs_size <= 0))
975 		return -EINVAL;
976 
977 	/* Check the user passed a healthy pointer.  */
978 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
979 		return -EFAULT;
980 
981 	/* Alloc space for the address array in kernel memory.  */
982 	kaddrs = kmalloc(addrs_size, GFP_USER | __GFP_NOWARN);
983 	if (unlikely(!kaddrs))
984 		return -ENOMEM;
985 
986 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
987 		kfree(kaddrs);
988 		return -EFAULT;
989 	}
990 
991 	/* Walk through the addrs buffer and count the number of addresses. */
992 	addr_buf = kaddrs;
993 	while (walk_size < addrs_size) {
994 		if (walk_size + sizeof(sa_family_t) > addrs_size) {
995 			kfree(kaddrs);
996 			return -EINVAL;
997 		}
998 
999 		sa_addr = addr_buf;
1000 		af = sctp_get_af_specific(sa_addr->sa_family);
1001 
1002 		/* If the address family is not supported or if this address
1003 		 * causes the address buffer to overflow return EINVAL.
1004 		 */
1005 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1006 			kfree(kaddrs);
1007 			return -EINVAL;
1008 		}
1009 		addrcnt++;
1010 		addr_buf += af->sockaddr_len;
1011 		walk_size += af->sockaddr_len;
1012 	}
1013 
1014 	/* Do the work. */
1015 	switch (op) {
1016 	case SCTP_BINDX_ADD_ADDR:
1017 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
1018 		if (err)
1019 			goto out;
1020 		err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
1021 		break;
1022 
1023 	case SCTP_BINDX_REM_ADDR:
1024 		err = sctp_bindx_rem(sk, kaddrs, addrcnt);
1025 		if (err)
1026 			goto out;
1027 		err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
1028 		break;
1029 
1030 	default:
1031 		err = -EINVAL;
1032 		break;
1033 	}
1034 
1035 out:
1036 	kfree(kaddrs);
1037 
1038 	return err;
1039 }
1040 
1041 /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
1042  *
1043  * Common routine for handling connect() and sctp_connectx().
1044  * Connect will come in with just a single address.
1045  */
1046 static int __sctp_connect(struct sock *sk,
1047 			  struct sockaddr *kaddrs,
1048 			  int addrs_size,
1049 			  sctp_assoc_t *assoc_id)
1050 {
1051 	struct net *net = sock_net(sk);
1052 	struct sctp_sock *sp;
1053 	struct sctp_endpoint *ep;
1054 	struct sctp_association *asoc = NULL;
1055 	struct sctp_association *asoc2;
1056 	struct sctp_transport *transport;
1057 	union sctp_addr to;
1058 	sctp_scope_t scope;
1059 	long timeo;
1060 	int err = 0;
1061 	int addrcnt = 0;
1062 	int walk_size = 0;
1063 	union sctp_addr *sa_addr = NULL;
1064 	void *addr_buf;
1065 	unsigned short port;
1066 	unsigned int f_flags = 0;
1067 
1068 	sp = sctp_sk(sk);
1069 	ep = sp->ep;
1070 
1071 	/* connect() cannot be done on a socket that is already in ESTABLISHED
1072 	 * state - UDP-style peeled off socket or a TCP-style socket that
1073 	 * is already connected.
1074 	 * It cannot be done even on a TCP-style listening socket.
1075 	 */
1076 	if (sctp_sstate(sk, ESTABLISHED) || sctp_sstate(sk, CLOSING) ||
1077 	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
1078 		err = -EISCONN;
1079 		goto out_free;
1080 	}
1081 
1082 	/* Walk through the addrs buffer and count the number of addresses. */
1083 	addr_buf = kaddrs;
1084 	while (walk_size < addrs_size) {
1085 		struct sctp_af *af;
1086 
1087 		if (walk_size + sizeof(sa_family_t) > addrs_size) {
1088 			err = -EINVAL;
1089 			goto out_free;
1090 		}
1091 
1092 		sa_addr = addr_buf;
1093 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
1094 
1095 		/* If the address family is not supported or if this address
1096 		 * causes the address buffer to overflow return EINVAL.
1097 		 */
1098 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1099 			err = -EINVAL;
1100 			goto out_free;
1101 		}
1102 
1103 		port = ntohs(sa_addr->v4.sin_port);
1104 
1105 		/* Save current address so we can work with it */
1106 		memcpy(&to, sa_addr, af->sockaddr_len);
1107 
1108 		err = sctp_verify_addr(sk, &to, af->sockaddr_len);
1109 		if (err)
1110 			goto out_free;
1111 
1112 		/* Make sure the destination port is correctly set
1113 		 * in all addresses.
1114 		 */
1115 		if (asoc && asoc->peer.port && asoc->peer.port != port) {
1116 			err = -EINVAL;
1117 			goto out_free;
1118 		}
1119 
1120 		/* Check if there already is a matching association on the
1121 		 * endpoint (other than the one created here).
1122 		 */
1123 		asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1124 		if (asoc2 && asoc2 != asoc) {
1125 			if (asoc2->state >= SCTP_STATE_ESTABLISHED)
1126 				err = -EISCONN;
1127 			else
1128 				err = -EALREADY;
1129 			goto out_free;
1130 		}
1131 
1132 		/* If we could not find a matching association on the endpoint,
1133 		 * make sure that there is no peeled-off association matching
1134 		 * the peer address even on another socket.
1135 		 */
1136 		if (sctp_endpoint_is_peeled_off(ep, &to)) {
1137 			err = -EADDRNOTAVAIL;
1138 			goto out_free;
1139 		}
1140 
1141 		if (!asoc) {
1142 			/* If a bind() or sctp_bindx() is not called prior to
1143 			 * an sctp_connectx() call, the system picks an
1144 			 * ephemeral port and will choose an address set
1145 			 * equivalent to binding with a wildcard address.
1146 			 */
1147 			if (!ep->base.bind_addr.port) {
1148 				if (sctp_autobind(sk)) {
1149 					err = -EAGAIN;
1150 					goto out_free;
1151 				}
1152 			} else {
1153 				/*
1154 				 * If an unprivileged user inherits a 1-many
1155 				 * style socket with open associations on a
1156 				 * privileged port, it MAY be permitted to
1157 				 * accept new associations, but it SHOULD NOT
1158 				 * be permitted to open new associations.
1159 				 */
1160 				if (ep->base.bind_addr.port <
1161 				    inet_prot_sock(net) &&
1162 				    !ns_capable(net->user_ns,
1163 				    CAP_NET_BIND_SERVICE)) {
1164 					err = -EACCES;
1165 					goto out_free;
1166 				}
1167 			}
1168 
1169 			scope = sctp_scope(&to);
1170 			asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1171 			if (!asoc) {
1172 				err = -ENOMEM;
1173 				goto out_free;
1174 			}
1175 
1176 			err = sctp_assoc_set_bind_addr_from_ep(asoc, scope,
1177 							      GFP_KERNEL);
1178 			if (err < 0) {
1179 				goto out_free;
1180 			}
1181 
1182 		}
1183 
1184 		/* Prime the peer's transport structures.  */
1185 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL,
1186 						SCTP_UNKNOWN);
1187 		if (!transport) {
1188 			err = -ENOMEM;
1189 			goto out_free;
1190 		}
1191 
1192 		addrcnt++;
1193 		addr_buf += af->sockaddr_len;
1194 		walk_size += af->sockaddr_len;
1195 	}
1196 
1197 	/* In case the user of sctp_connectx() wants an association
1198 	 * id back, assign one now.
1199 	 */
1200 	if (assoc_id) {
1201 		err = sctp_assoc_set_id(asoc, GFP_KERNEL);
1202 		if (err < 0)
1203 			goto out_free;
1204 	}
1205 
1206 	err = sctp_primitive_ASSOCIATE(net, asoc, NULL);
1207 	if (err < 0) {
1208 		goto out_free;
1209 	}
1210 
1211 	/* Initialize sk's dport and daddr for getpeername() */
1212 	inet_sk(sk)->inet_dport = htons(asoc->peer.port);
1213 	sp->pf->to_sk_daddr(sa_addr, sk);
1214 	sk->sk_err = 0;
1215 
1216 	/* in-kernel sockets don't generally have a file allocated to them
1217 	 * if all they do is call sock_create_kern().
1218 	 */
1219 	if (sk->sk_socket->file)
1220 		f_flags = sk->sk_socket->file->f_flags;
1221 
1222 	timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK);
1223 
1224 	if (assoc_id)
1225 		*assoc_id = asoc->assoc_id;
1226 	err = sctp_wait_for_connect(asoc, &timeo);
1227 	/* Note: the asoc may be freed after the return of
1228 	 * sctp_wait_for_connect.
1229 	 */
1230 
1231 	/* Don't free association on exit. */
1232 	asoc = NULL;
1233 
1234 out_free:
1235 	pr_debug("%s: took out_free path with asoc:%p kaddrs:%p err:%d\n",
1236 		 __func__, asoc, kaddrs, err);
1237 
1238 	if (asoc) {
1239 		/* sctp_primitive_ASSOCIATE may have added this association
1240 		 * To the hash table, try to unhash it, just in case, its a noop
1241 		 * if it wasn't hashed so we're safe
1242 		 */
1243 		sctp_association_free(asoc);
1244 	}
1245 	return err;
1246 }
1247 
1248 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
1249  *
1250  * API 8.9
1251  * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt,
1252  * 			sctp_assoc_t *asoc);
1253  *
1254  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
1255  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
1256  * or IPv6 addresses.
1257  *
1258  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
1259  * Section 3.1.2 for this usage.
1260  *
1261  * addrs is a pointer to an array of one or more socket addresses. Each
1262  * address is contained in its appropriate structure (i.e. struct
1263  * sockaddr_in or struct sockaddr_in6) the family of the address type
1264  * must be used to distengish the address length (note that this
1265  * representation is termed a "packed array" of addresses). The caller
1266  * specifies the number of addresses in the array with addrcnt.
1267  *
1268  * On success, sctp_connectx() returns 0. It also sets the assoc_id to
1269  * the association id of the new association.  On failure, sctp_connectx()
1270  * returns -1, and sets errno to the appropriate error code.  The assoc_id
1271  * is not touched by the kernel.
1272  *
1273  * For SCTP, the port given in each socket address must be the same, or
1274  * sctp_connectx() will fail, setting errno to EINVAL.
1275  *
1276  * An application can use sctp_connectx to initiate an association with
1277  * an endpoint that is multi-homed.  Much like sctp_bindx() this call
1278  * allows a caller to specify multiple addresses at which a peer can be
1279  * reached.  The way the SCTP stack uses the list of addresses to set up
1280  * the association is implementation dependent.  This function only
1281  * specifies that the stack will try to make use of all the addresses in
1282  * the list when needed.
1283  *
1284  * Note that the list of addresses passed in is only used for setting up
1285  * the association.  It does not necessarily equal the set of addresses
1286  * the peer uses for the resulting association.  If the caller wants to
1287  * find out the set of peer addresses, it must use sctp_getpaddrs() to
1288  * retrieve them after the association has been set up.
1289  *
1290  * Basically do nothing but copying the addresses from user to kernel
1291  * land and invoking either sctp_connectx(). This is used for tunneling
1292  * the sctp_connectx() request through sctp_setsockopt() from userspace.
1293  *
1294  * We don't use copy_from_user() for optimization: we first do the
1295  * sanity checks (buffer size -fast- and access check-healthy
1296  * pointer); if all of those succeed, then we can alloc the memory
1297  * (expensive operation) needed to copy the data to kernel. Then we do
1298  * the copying without checking the user space area
1299  * (__copy_from_user()).
1300  *
1301  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
1302  * it.
1303  *
1304  * sk        The sk of the socket
1305  * addrs     The pointer to the addresses in user land
1306  * addrssize Size of the addrs buffer
1307  *
1308  * Returns >=0 if ok, <0 errno code on error.
1309  */
1310 static int __sctp_setsockopt_connectx(struct sock *sk,
1311 				      struct sockaddr __user *addrs,
1312 				      int addrs_size,
1313 				      sctp_assoc_t *assoc_id)
1314 {
1315 	struct sockaddr *kaddrs;
1316 	gfp_t gfp = GFP_KERNEL;
1317 	int err = 0;
1318 
1319 	pr_debug("%s: sk:%p addrs:%p addrs_size:%d\n",
1320 		 __func__, sk, addrs, addrs_size);
1321 
1322 	if (unlikely(addrs_size <= 0))
1323 		return -EINVAL;
1324 
1325 	/* Check the user passed a healthy pointer.  */
1326 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
1327 		return -EFAULT;
1328 
1329 	/* Alloc space for the address array in kernel memory.  */
1330 	if (sk->sk_socket->file)
1331 		gfp = GFP_USER | __GFP_NOWARN;
1332 	kaddrs = kmalloc(addrs_size, gfp);
1333 	if (unlikely(!kaddrs))
1334 		return -ENOMEM;
1335 
1336 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
1337 		err = -EFAULT;
1338 	} else {
1339 		err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
1340 	}
1341 
1342 	kfree(kaddrs);
1343 
1344 	return err;
1345 }
1346 
1347 /*
1348  * This is an older interface.  It's kept for backward compatibility
1349  * to the option that doesn't provide association id.
1350  */
1351 static int sctp_setsockopt_connectx_old(struct sock *sk,
1352 					struct sockaddr __user *addrs,
1353 					int addrs_size)
1354 {
1355 	return __sctp_setsockopt_connectx(sk, addrs, addrs_size, NULL);
1356 }
1357 
1358 /*
1359  * New interface for the API.  The since the API is done with a socket
1360  * option, to make it simple we feed back the association id is as a return
1361  * indication to the call.  Error is always negative and association id is
1362  * always positive.
1363  */
1364 static int sctp_setsockopt_connectx(struct sock *sk,
1365 				    struct sockaddr __user *addrs,
1366 				    int addrs_size)
1367 {
1368 	sctp_assoc_t assoc_id = 0;
1369 	int err = 0;
1370 
1371 	err = __sctp_setsockopt_connectx(sk, addrs, addrs_size, &assoc_id);
1372 
1373 	if (err)
1374 		return err;
1375 	else
1376 		return assoc_id;
1377 }
1378 
1379 /*
1380  * New (hopefully final) interface for the API.
1381  * We use the sctp_getaddrs_old structure so that use-space library
1382  * can avoid any unnecessary allocations. The only different part
1383  * is that we store the actual length of the address buffer into the
1384  * addrs_num structure member. That way we can re-use the existing
1385  * code.
1386  */
1387 #ifdef CONFIG_COMPAT
1388 struct compat_sctp_getaddrs_old {
1389 	sctp_assoc_t	assoc_id;
1390 	s32		addr_num;
1391 	compat_uptr_t	addrs;		/* struct sockaddr * */
1392 };
1393 #endif
1394 
1395 static int sctp_getsockopt_connectx3(struct sock *sk, int len,
1396 				     char __user *optval,
1397 				     int __user *optlen)
1398 {
1399 	struct sctp_getaddrs_old param;
1400 	sctp_assoc_t assoc_id = 0;
1401 	int err = 0;
1402 
1403 #ifdef CONFIG_COMPAT
1404 	if (in_compat_syscall()) {
1405 		struct compat_sctp_getaddrs_old param32;
1406 
1407 		if (len < sizeof(param32))
1408 			return -EINVAL;
1409 		if (copy_from_user(&param32, optval, sizeof(param32)))
1410 			return -EFAULT;
1411 
1412 		param.assoc_id = param32.assoc_id;
1413 		param.addr_num = param32.addr_num;
1414 		param.addrs = compat_ptr(param32.addrs);
1415 	} else
1416 #endif
1417 	{
1418 		if (len < sizeof(param))
1419 			return -EINVAL;
1420 		if (copy_from_user(&param, optval, sizeof(param)))
1421 			return -EFAULT;
1422 	}
1423 
1424 	err = __sctp_setsockopt_connectx(sk, (struct sockaddr __user *)
1425 					 param.addrs, param.addr_num,
1426 					 &assoc_id);
1427 	if (err == 0 || err == -EINPROGRESS) {
1428 		if (copy_to_user(optval, &assoc_id, sizeof(assoc_id)))
1429 			return -EFAULT;
1430 		if (put_user(sizeof(assoc_id), optlen))
1431 			return -EFAULT;
1432 	}
1433 
1434 	return err;
1435 }
1436 
1437 /* API 3.1.4 close() - UDP Style Syntax
1438  * Applications use close() to perform graceful shutdown (as described in
1439  * Section 10.1 of [SCTP]) on ALL the associations currently represented
1440  * by a UDP-style socket.
1441  *
1442  * The syntax is
1443  *
1444  *   ret = close(int sd);
1445  *
1446  *   sd      - the socket descriptor of the associations to be closed.
1447  *
1448  * To gracefully shutdown a specific association represented by the
1449  * UDP-style socket, an application should use the sendmsg() call,
1450  * passing no user data, but including the appropriate flag in the
1451  * ancillary data (see Section xxxx).
1452  *
1453  * If sd in the close() call is a branched-off socket representing only
1454  * one association, the shutdown is performed on that association only.
1455  *
1456  * 4.1.6 close() - TCP Style Syntax
1457  *
1458  * Applications use close() to gracefully close down an association.
1459  *
1460  * The syntax is:
1461  *
1462  *    int close(int sd);
1463  *
1464  *      sd      - the socket descriptor of the association to be closed.
1465  *
1466  * After an application calls close() on a socket descriptor, no further
1467  * socket operations will succeed on that descriptor.
1468  *
1469  * API 7.1.4 SO_LINGER
1470  *
1471  * An application using the TCP-style socket can use this option to
1472  * perform the SCTP ABORT primitive.  The linger option structure is:
1473  *
1474  *  struct  linger {
1475  *     int     l_onoff;                // option on/off
1476  *     int     l_linger;               // linger time
1477  * };
1478  *
1479  * To enable the option, set l_onoff to 1.  If the l_linger value is set
1480  * to 0, calling close() is the same as the ABORT primitive.  If the
1481  * value is set to a negative value, the setsockopt() call will return
1482  * an error.  If the value is set to a positive value linger_time, the
1483  * close() can be blocked for at most linger_time ms.  If the graceful
1484  * shutdown phase does not finish during this period, close() will
1485  * return but the graceful shutdown phase continues in the system.
1486  */
1487 static void sctp_close(struct sock *sk, long timeout)
1488 {
1489 	struct net *net = sock_net(sk);
1490 	struct sctp_endpoint *ep;
1491 	struct sctp_association *asoc;
1492 	struct list_head *pos, *temp;
1493 	unsigned int data_was_unread;
1494 
1495 	pr_debug("%s: sk:%p, timeout:%ld\n", __func__, sk, timeout);
1496 
1497 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
1498 	sk->sk_shutdown = SHUTDOWN_MASK;
1499 	sk->sk_state = SCTP_SS_CLOSING;
1500 
1501 	ep = sctp_sk(sk)->ep;
1502 
1503 	/* Clean up any skbs sitting on the receive queue.  */
1504 	data_was_unread = sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
1505 	data_was_unread += sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
1506 
1507 	/* Walk all associations on an endpoint.  */
1508 	list_for_each_safe(pos, temp, &ep->asocs) {
1509 		asoc = list_entry(pos, struct sctp_association, asocs);
1510 
1511 		if (sctp_style(sk, TCP)) {
1512 			/* A closed association can still be in the list if
1513 			 * it belongs to a TCP-style listening socket that is
1514 			 * not yet accepted. If so, free it. If not, send an
1515 			 * ABORT or SHUTDOWN based on the linger options.
1516 			 */
1517 			if (sctp_state(asoc, CLOSED)) {
1518 				sctp_association_free(asoc);
1519 				continue;
1520 			}
1521 		}
1522 
1523 		if (data_was_unread || !skb_queue_empty(&asoc->ulpq.lobby) ||
1524 		    !skb_queue_empty(&asoc->ulpq.reasm) ||
1525 		    (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime)) {
1526 			struct sctp_chunk *chunk;
1527 
1528 			chunk = sctp_make_abort_user(asoc, NULL, 0);
1529 			sctp_primitive_ABORT(net, asoc, chunk);
1530 		} else
1531 			sctp_primitive_SHUTDOWN(net, asoc, NULL);
1532 	}
1533 
1534 	/* On a TCP-style socket, block for at most linger_time if set. */
1535 	if (sctp_style(sk, TCP) && timeout)
1536 		sctp_wait_for_close(sk, timeout);
1537 
1538 	/* This will run the backlog queue.  */
1539 	release_sock(sk);
1540 
1541 	/* Supposedly, no process has access to the socket, but
1542 	 * the net layers still may.
1543 	 * Also, sctp_destroy_sock() needs to be called with addr_wq_lock
1544 	 * held and that should be grabbed before socket lock.
1545 	 */
1546 	spin_lock_bh(&net->sctp.addr_wq_lock);
1547 	bh_lock_sock_nested(sk);
1548 
1549 	/* Hold the sock, since sk_common_release() will put sock_put()
1550 	 * and we have just a little more cleanup.
1551 	 */
1552 	sock_hold(sk);
1553 	sk_common_release(sk);
1554 
1555 	bh_unlock_sock(sk);
1556 	spin_unlock_bh(&net->sctp.addr_wq_lock);
1557 
1558 	sock_put(sk);
1559 
1560 	SCTP_DBG_OBJCNT_DEC(sock);
1561 }
1562 
1563 /* Handle EPIPE error. */
1564 static int sctp_error(struct sock *sk, int flags, int err)
1565 {
1566 	if (err == -EPIPE)
1567 		err = sock_error(sk) ? : -EPIPE;
1568 	if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
1569 		send_sig(SIGPIPE, current, 0);
1570 	return err;
1571 }
1572 
1573 /* API 3.1.3 sendmsg() - UDP Style Syntax
1574  *
1575  * An application uses sendmsg() and recvmsg() calls to transmit data to
1576  * and receive data from its peer.
1577  *
1578  *  ssize_t sendmsg(int socket, const struct msghdr *message,
1579  *                  int flags);
1580  *
1581  *  socket  - the socket descriptor of the endpoint.
1582  *  message - pointer to the msghdr structure which contains a single
1583  *            user message and possibly some ancillary data.
1584  *
1585  *            See Section 5 for complete description of the data
1586  *            structures.
1587  *
1588  *  flags   - flags sent or received with the user message, see Section
1589  *            5 for complete description of the flags.
1590  *
1591  * Note:  This function could use a rewrite especially when explicit
1592  * connect support comes in.
1593  */
1594 /* BUG:  We do not implement the equivalent of sk_stream_wait_memory(). */
1595 
1596 static int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
1597 
1598 static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
1599 {
1600 	struct net *net = sock_net(sk);
1601 	struct sctp_sock *sp;
1602 	struct sctp_endpoint *ep;
1603 	struct sctp_association *new_asoc = NULL, *asoc = NULL;
1604 	struct sctp_transport *transport, *chunk_tp;
1605 	struct sctp_chunk *chunk;
1606 	union sctp_addr to;
1607 	struct sockaddr *msg_name = NULL;
1608 	struct sctp_sndrcvinfo default_sinfo;
1609 	struct sctp_sndrcvinfo *sinfo;
1610 	struct sctp_initmsg *sinit;
1611 	sctp_assoc_t associd = 0;
1612 	sctp_cmsgs_t cmsgs = { NULL };
1613 	sctp_scope_t scope;
1614 	bool fill_sinfo_ttl = false, wait_connect = false;
1615 	struct sctp_datamsg *datamsg;
1616 	int msg_flags = msg->msg_flags;
1617 	__u16 sinfo_flags = 0;
1618 	long timeo;
1619 	int err;
1620 
1621 	err = 0;
1622 	sp = sctp_sk(sk);
1623 	ep = sp->ep;
1624 
1625 	pr_debug("%s: sk:%p, msg:%p, msg_len:%zu ep:%p\n", __func__, sk,
1626 		 msg, msg_len, ep);
1627 
1628 	/* We cannot send a message over a TCP-style listening socket. */
1629 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) {
1630 		err = -EPIPE;
1631 		goto out_nounlock;
1632 	}
1633 
1634 	/* Parse out the SCTP CMSGs.  */
1635 	err = sctp_msghdr_parse(msg, &cmsgs);
1636 	if (err) {
1637 		pr_debug("%s: msghdr parse err:%x\n", __func__, err);
1638 		goto out_nounlock;
1639 	}
1640 
1641 	/* Fetch the destination address for this packet.  This
1642 	 * address only selects the association--it is not necessarily
1643 	 * the address we will send to.
1644 	 * For a peeled-off socket, msg_name is ignored.
1645 	 */
1646 	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
1647 		int msg_namelen = msg->msg_namelen;
1648 
1649 		err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
1650 				       msg_namelen);
1651 		if (err)
1652 			return err;
1653 
1654 		if (msg_namelen > sizeof(to))
1655 			msg_namelen = sizeof(to);
1656 		memcpy(&to, msg->msg_name, msg_namelen);
1657 		msg_name = msg->msg_name;
1658 	}
1659 
1660 	sinit = cmsgs.init;
1661 	if (cmsgs.sinfo != NULL) {
1662 		memset(&default_sinfo, 0, sizeof(default_sinfo));
1663 		default_sinfo.sinfo_stream = cmsgs.sinfo->snd_sid;
1664 		default_sinfo.sinfo_flags = cmsgs.sinfo->snd_flags;
1665 		default_sinfo.sinfo_ppid = cmsgs.sinfo->snd_ppid;
1666 		default_sinfo.sinfo_context = cmsgs.sinfo->snd_context;
1667 		default_sinfo.sinfo_assoc_id = cmsgs.sinfo->snd_assoc_id;
1668 
1669 		sinfo = &default_sinfo;
1670 		fill_sinfo_ttl = true;
1671 	} else {
1672 		sinfo = cmsgs.srinfo;
1673 	}
1674 	/* Did the user specify SNDINFO/SNDRCVINFO? */
1675 	if (sinfo) {
1676 		sinfo_flags = sinfo->sinfo_flags;
1677 		associd = sinfo->sinfo_assoc_id;
1678 	}
1679 
1680 	pr_debug("%s: msg_len:%zu, sinfo_flags:0x%x\n", __func__,
1681 		 msg_len, sinfo_flags);
1682 
1683 	/* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */
1684 	if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) {
1685 		err = -EINVAL;
1686 		goto out_nounlock;
1687 	}
1688 
1689 	/* If SCTP_EOF is set, no data can be sent. Disallow sending zero
1690 	 * length messages when SCTP_EOF|SCTP_ABORT is not set.
1691 	 * If SCTP_ABORT is set, the message length could be non zero with
1692 	 * the msg_iov set to the user abort reason.
1693 	 */
1694 	if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) ||
1695 	    (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) {
1696 		err = -EINVAL;
1697 		goto out_nounlock;
1698 	}
1699 
1700 	/* If SCTP_ADDR_OVER is set, there must be an address
1701 	 * specified in msg_name.
1702 	 */
1703 	if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) {
1704 		err = -EINVAL;
1705 		goto out_nounlock;
1706 	}
1707 
1708 	transport = NULL;
1709 
1710 	pr_debug("%s: about to look up association\n", __func__);
1711 
1712 	lock_sock(sk);
1713 
1714 	/* If a msg_name has been specified, assume this is to be used.  */
1715 	if (msg_name) {
1716 		/* Look for a matching association on the endpoint. */
1717 		asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1718 
1719 		/* If we could not find a matching association on the
1720 		 * endpoint, make sure that it is not a TCP-style
1721 		 * socket that already has an association or there is
1722 		 * no peeled-off association on another socket.
1723 		 */
1724 		if (!asoc &&
1725 		    ((sctp_style(sk, TCP) &&
1726 		      (sctp_sstate(sk, ESTABLISHED) ||
1727 		       sctp_sstate(sk, CLOSING))) ||
1728 		     sctp_endpoint_is_peeled_off(ep, &to))) {
1729 			err = -EADDRNOTAVAIL;
1730 			goto out_unlock;
1731 		}
1732 	} else {
1733 		asoc = sctp_id2assoc(sk, associd);
1734 		if (!asoc) {
1735 			err = -EPIPE;
1736 			goto out_unlock;
1737 		}
1738 	}
1739 
1740 	if (asoc) {
1741 		pr_debug("%s: just looked up association:%p\n", __func__, asoc);
1742 
1743 		/* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED
1744 		 * socket that has an association in CLOSED state. This can
1745 		 * happen when an accepted socket has an association that is
1746 		 * already CLOSED.
1747 		 */
1748 		if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) {
1749 			err = -EPIPE;
1750 			goto out_unlock;
1751 		}
1752 
1753 		if (sinfo_flags & SCTP_EOF) {
1754 			pr_debug("%s: shutting down association:%p\n",
1755 				 __func__, asoc);
1756 
1757 			sctp_primitive_SHUTDOWN(net, asoc, NULL);
1758 			err = 0;
1759 			goto out_unlock;
1760 		}
1761 		if (sinfo_flags & SCTP_ABORT) {
1762 
1763 			chunk = sctp_make_abort_user(asoc, msg, msg_len);
1764 			if (!chunk) {
1765 				err = -ENOMEM;
1766 				goto out_unlock;
1767 			}
1768 
1769 			pr_debug("%s: aborting association:%p\n",
1770 				 __func__, asoc);
1771 
1772 			sctp_primitive_ABORT(net, asoc, chunk);
1773 			err = 0;
1774 			goto out_unlock;
1775 		}
1776 	}
1777 
1778 	/* Do we need to create the association?  */
1779 	if (!asoc) {
1780 		pr_debug("%s: there is no association yet\n", __func__);
1781 
1782 		if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) {
1783 			err = -EINVAL;
1784 			goto out_unlock;
1785 		}
1786 
1787 		/* Check for invalid stream against the stream counts,
1788 		 * either the default or the user specified stream counts.
1789 		 */
1790 		if (sinfo) {
1791 			if (!sinit || !sinit->sinit_num_ostreams) {
1792 				/* Check against the defaults. */
1793 				if (sinfo->sinfo_stream >=
1794 				    sp->initmsg.sinit_num_ostreams) {
1795 					err = -EINVAL;
1796 					goto out_unlock;
1797 				}
1798 			} else {
1799 				/* Check against the requested.  */
1800 				if (sinfo->sinfo_stream >=
1801 				    sinit->sinit_num_ostreams) {
1802 					err = -EINVAL;
1803 					goto out_unlock;
1804 				}
1805 			}
1806 		}
1807 
1808 		/*
1809 		 * API 3.1.2 bind() - UDP Style Syntax
1810 		 * If a bind() or sctp_bindx() is not called prior to a
1811 		 * sendmsg() call that initiates a new association, the
1812 		 * system picks an ephemeral port and will choose an address
1813 		 * set equivalent to binding with a wildcard address.
1814 		 */
1815 		if (!ep->base.bind_addr.port) {
1816 			if (sctp_autobind(sk)) {
1817 				err = -EAGAIN;
1818 				goto out_unlock;
1819 			}
1820 		} else {
1821 			/*
1822 			 * If an unprivileged user inherits a one-to-many
1823 			 * style socket with open associations on a privileged
1824 			 * port, it MAY be permitted to accept new associations,
1825 			 * but it SHOULD NOT be permitted to open new
1826 			 * associations.
1827 			 */
1828 			if (ep->base.bind_addr.port < inet_prot_sock(net) &&
1829 			    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) {
1830 				err = -EACCES;
1831 				goto out_unlock;
1832 			}
1833 		}
1834 
1835 		scope = sctp_scope(&to);
1836 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1837 		if (!new_asoc) {
1838 			err = -ENOMEM;
1839 			goto out_unlock;
1840 		}
1841 		asoc = new_asoc;
1842 		err = sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL);
1843 		if (err < 0) {
1844 			err = -ENOMEM;
1845 			goto out_free;
1846 		}
1847 
1848 		/* If the SCTP_INIT ancillary data is specified, set all
1849 		 * the association init values accordingly.
1850 		 */
1851 		if (sinit) {
1852 			if (sinit->sinit_num_ostreams) {
1853 				asoc->c.sinit_num_ostreams =
1854 					sinit->sinit_num_ostreams;
1855 			}
1856 			if (sinit->sinit_max_instreams) {
1857 				asoc->c.sinit_max_instreams =
1858 					sinit->sinit_max_instreams;
1859 			}
1860 			if (sinit->sinit_max_attempts) {
1861 				asoc->max_init_attempts
1862 					= sinit->sinit_max_attempts;
1863 			}
1864 			if (sinit->sinit_max_init_timeo) {
1865 				asoc->max_init_timeo =
1866 				 msecs_to_jiffies(sinit->sinit_max_init_timeo);
1867 			}
1868 		}
1869 
1870 		/* Prime the peer's transport structures.  */
1871 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN);
1872 		if (!transport) {
1873 			err = -ENOMEM;
1874 			goto out_free;
1875 		}
1876 	}
1877 
1878 	/* ASSERT: we have a valid association at this point.  */
1879 	pr_debug("%s: we have a valid association\n", __func__);
1880 
1881 	if (!sinfo) {
1882 		/* If the user didn't specify SNDINFO/SNDRCVINFO, make up
1883 		 * one with some defaults.
1884 		 */
1885 		memset(&default_sinfo, 0, sizeof(default_sinfo));
1886 		default_sinfo.sinfo_stream = asoc->default_stream;
1887 		default_sinfo.sinfo_flags = asoc->default_flags;
1888 		default_sinfo.sinfo_ppid = asoc->default_ppid;
1889 		default_sinfo.sinfo_context = asoc->default_context;
1890 		default_sinfo.sinfo_timetolive = asoc->default_timetolive;
1891 		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
1892 
1893 		sinfo = &default_sinfo;
1894 	} else if (fill_sinfo_ttl) {
1895 		/* In case SNDINFO was specified, we still need to fill
1896 		 * it with a default ttl from the assoc here.
1897 		 */
1898 		sinfo->sinfo_timetolive = asoc->default_timetolive;
1899 	}
1900 
1901 	/* API 7.1.7, the sndbuf size per association bounds the
1902 	 * maximum size of data that can be sent in a single send call.
1903 	 */
1904 	if (msg_len > sk->sk_sndbuf) {
1905 		err = -EMSGSIZE;
1906 		goto out_free;
1907 	}
1908 
1909 	if (asoc->pmtu_pending)
1910 		sctp_assoc_pending_pmtu(asoc);
1911 
1912 	/* If fragmentation is disabled and the message length exceeds the
1913 	 * association fragmentation point, return EMSGSIZE.  The I-D
1914 	 * does not specify what this error is, but this looks like
1915 	 * a great fit.
1916 	 */
1917 	if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
1918 		err = -EMSGSIZE;
1919 		goto out_free;
1920 	}
1921 
1922 	/* Check for invalid stream. */
1923 	if (sinfo->sinfo_stream >= asoc->stream.outcnt) {
1924 		err = -EINVAL;
1925 		goto out_free;
1926 	}
1927 
1928 	if (sctp_wspace(asoc) < msg_len)
1929 		sctp_prsctp_prune(asoc, sinfo, msg_len - sctp_wspace(asoc));
1930 
1931 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1932 	if (!sctp_wspace(asoc)) {
1933 		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
1934 		if (err)
1935 			goto out_free;
1936 	}
1937 
1938 	/* If an address is passed with the sendto/sendmsg call, it is used
1939 	 * to override the primary destination address in the TCP model, or
1940 	 * when SCTP_ADDR_OVER flag is set in the UDP model.
1941 	 */
1942 	if ((sctp_style(sk, TCP) && msg_name) ||
1943 	    (sinfo_flags & SCTP_ADDR_OVER)) {
1944 		chunk_tp = sctp_assoc_lookup_paddr(asoc, &to);
1945 		if (!chunk_tp) {
1946 			err = -EINVAL;
1947 			goto out_free;
1948 		}
1949 	} else
1950 		chunk_tp = NULL;
1951 
1952 	/* Auto-connect, if we aren't connected already. */
1953 	if (sctp_state(asoc, CLOSED)) {
1954 		err = sctp_primitive_ASSOCIATE(net, asoc, NULL);
1955 		if (err < 0)
1956 			goto out_free;
1957 
1958 		wait_connect = true;
1959 		pr_debug("%s: we associated primitively\n", __func__);
1960 	}
1961 
1962 	/* Break the message into multiple chunks of maximum size. */
1963 	datamsg = sctp_datamsg_from_user(asoc, sinfo, &msg->msg_iter);
1964 	if (IS_ERR(datamsg)) {
1965 		err = PTR_ERR(datamsg);
1966 		goto out_free;
1967 	}
1968 	asoc->force_delay = !!(msg->msg_flags & MSG_MORE);
1969 
1970 	/* Now send the (possibly) fragmented message. */
1971 	list_for_each_entry(chunk, &datamsg->chunks, frag_list) {
1972 		sctp_chunk_hold(chunk);
1973 
1974 		/* Do accounting for the write space.  */
1975 		sctp_set_owner_w(chunk);
1976 
1977 		chunk->transport = chunk_tp;
1978 	}
1979 
1980 	/* Send it to the lower layers.  Note:  all chunks
1981 	 * must either fail or succeed.   The lower layer
1982 	 * works that way today.  Keep it that way or this
1983 	 * breaks.
1984 	 */
1985 	err = sctp_primitive_SEND(net, asoc, datamsg);
1986 	/* Did the lower layer accept the chunk? */
1987 	if (err) {
1988 		sctp_datamsg_free(datamsg);
1989 		goto out_free;
1990 	}
1991 
1992 	pr_debug("%s: we sent primitively\n", __func__);
1993 
1994 	sctp_datamsg_put(datamsg);
1995 	err = msg_len;
1996 
1997 	if (unlikely(wait_connect)) {
1998 		timeo = sock_sndtimeo(sk, msg_flags & MSG_DONTWAIT);
1999 		sctp_wait_for_connect(asoc, &timeo);
2000 	}
2001 
2002 	/* If we are already past ASSOCIATE, the lower
2003 	 * layers are responsible for association cleanup.
2004 	 */
2005 	goto out_unlock;
2006 
2007 out_free:
2008 	if (new_asoc)
2009 		sctp_association_free(asoc);
2010 out_unlock:
2011 	release_sock(sk);
2012 
2013 out_nounlock:
2014 	return sctp_error(sk, msg_flags, err);
2015 
2016 #if 0
2017 do_sock_err:
2018 	if (msg_len)
2019 		err = msg_len;
2020 	else
2021 		err = sock_error(sk);
2022 	goto out;
2023 
2024 do_interrupted:
2025 	if (msg_len)
2026 		err = msg_len;
2027 	goto out;
2028 #endif /* 0 */
2029 }
2030 
2031 /* This is an extended version of skb_pull() that removes the data from the
2032  * start of a skb even when data is spread across the list of skb's in the
2033  * frag_list. len specifies the total amount of data that needs to be removed.
2034  * when 'len' bytes could be removed from the skb, it returns 0.
2035  * If 'len' exceeds the total skb length,  it returns the no. of bytes that
2036  * could not be removed.
2037  */
2038 static int sctp_skb_pull(struct sk_buff *skb, int len)
2039 {
2040 	struct sk_buff *list;
2041 	int skb_len = skb_headlen(skb);
2042 	int rlen;
2043 
2044 	if (len <= skb_len) {
2045 		__skb_pull(skb, len);
2046 		return 0;
2047 	}
2048 	len -= skb_len;
2049 	__skb_pull(skb, skb_len);
2050 
2051 	skb_walk_frags(skb, list) {
2052 		rlen = sctp_skb_pull(list, len);
2053 		skb->len -= (len-rlen);
2054 		skb->data_len -= (len-rlen);
2055 
2056 		if (!rlen)
2057 			return 0;
2058 
2059 		len = rlen;
2060 	}
2061 
2062 	return len;
2063 }
2064 
2065 /* API 3.1.3  recvmsg() - UDP Style Syntax
2066  *
2067  *  ssize_t recvmsg(int socket, struct msghdr *message,
2068  *                    int flags);
2069  *
2070  *  socket  - the socket descriptor of the endpoint.
2071  *  message - pointer to the msghdr structure which contains a single
2072  *            user message and possibly some ancillary data.
2073  *
2074  *            See Section 5 for complete description of the data
2075  *            structures.
2076  *
2077  *  flags   - flags sent or received with the user message, see Section
2078  *            5 for complete description of the flags.
2079  */
2080 static int sctp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
2081 			int noblock, int flags, int *addr_len)
2082 {
2083 	struct sctp_ulpevent *event = NULL;
2084 	struct sctp_sock *sp = sctp_sk(sk);
2085 	struct sk_buff *skb, *head_skb;
2086 	int copied;
2087 	int err = 0;
2088 	int skb_len;
2089 
2090 	pr_debug("%s: sk:%p, msghdr:%p, len:%zd, noblock:%d, flags:0x%x, "
2091 		 "addr_len:%p)\n", __func__, sk, msg, len, noblock, flags,
2092 		 addr_len);
2093 
2094 	lock_sock(sk);
2095 
2096 	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED) &&
2097 	    !sctp_sstate(sk, CLOSING) && !sctp_sstate(sk, CLOSED)) {
2098 		err = -ENOTCONN;
2099 		goto out;
2100 	}
2101 
2102 	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
2103 	if (!skb)
2104 		goto out;
2105 
2106 	/* Get the total length of the skb including any skb's in the
2107 	 * frag_list.
2108 	 */
2109 	skb_len = skb->len;
2110 
2111 	copied = skb_len;
2112 	if (copied > len)
2113 		copied = len;
2114 
2115 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
2116 
2117 	event = sctp_skb2event(skb);
2118 
2119 	if (err)
2120 		goto out_free;
2121 
2122 	if (event->chunk && event->chunk->head_skb)
2123 		head_skb = event->chunk->head_skb;
2124 	else
2125 		head_skb = skb;
2126 	sock_recv_ts_and_drops(msg, sk, head_skb);
2127 	if (sctp_ulpevent_is_notification(event)) {
2128 		msg->msg_flags |= MSG_NOTIFICATION;
2129 		sp->pf->event_msgname(event, msg->msg_name, addr_len);
2130 	} else {
2131 		sp->pf->skb_msgname(head_skb, msg->msg_name, addr_len);
2132 	}
2133 
2134 	/* Check if we allow SCTP_NXTINFO. */
2135 	if (sp->recvnxtinfo)
2136 		sctp_ulpevent_read_nxtinfo(event, msg, sk);
2137 	/* Check if we allow SCTP_RCVINFO. */
2138 	if (sp->recvrcvinfo)
2139 		sctp_ulpevent_read_rcvinfo(event, msg);
2140 	/* Check if we allow SCTP_SNDRCVINFO. */
2141 	if (sp->subscribe.sctp_data_io_event)
2142 		sctp_ulpevent_read_sndrcvinfo(event, msg);
2143 
2144 	err = copied;
2145 
2146 	/* If skb's length exceeds the user's buffer, update the skb and
2147 	 * push it back to the receive_queue so that the next call to
2148 	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
2149 	 */
2150 	if (skb_len > copied) {
2151 		msg->msg_flags &= ~MSG_EOR;
2152 		if (flags & MSG_PEEK)
2153 			goto out_free;
2154 		sctp_skb_pull(skb, copied);
2155 		skb_queue_head(&sk->sk_receive_queue, skb);
2156 
2157 		/* When only partial message is copied to the user, increase
2158 		 * rwnd by that amount. If all the data in the skb is read,
2159 		 * rwnd is updated when the event is freed.
2160 		 */
2161 		if (!sctp_ulpevent_is_notification(event))
2162 			sctp_assoc_rwnd_increase(event->asoc, copied);
2163 		goto out;
2164 	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
2165 		   (event->msg_flags & MSG_EOR))
2166 		msg->msg_flags |= MSG_EOR;
2167 	else
2168 		msg->msg_flags &= ~MSG_EOR;
2169 
2170 out_free:
2171 	if (flags & MSG_PEEK) {
2172 		/* Release the skb reference acquired after peeking the skb in
2173 		 * sctp_skb_recv_datagram().
2174 		 */
2175 		kfree_skb(skb);
2176 	} else {
2177 		/* Free the event which includes releasing the reference to
2178 		 * the owner of the skb, freeing the skb and updating the
2179 		 * rwnd.
2180 		 */
2181 		sctp_ulpevent_free(event);
2182 	}
2183 out:
2184 	release_sock(sk);
2185 	return err;
2186 }
2187 
2188 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
2189  *
2190  * This option is a on/off flag.  If enabled no SCTP message
2191  * fragmentation will be performed.  Instead if a message being sent
2192  * exceeds the current PMTU size, the message will NOT be sent and
2193  * instead a error will be indicated to the user.
2194  */
2195 static int sctp_setsockopt_disable_fragments(struct sock *sk,
2196 					     char __user *optval,
2197 					     unsigned int optlen)
2198 {
2199 	int val;
2200 
2201 	if (optlen < sizeof(int))
2202 		return -EINVAL;
2203 
2204 	if (get_user(val, (int __user *)optval))
2205 		return -EFAULT;
2206 
2207 	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
2208 
2209 	return 0;
2210 }
2211 
2212 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
2213 				  unsigned int optlen)
2214 {
2215 	struct sctp_association *asoc;
2216 	struct sctp_ulpevent *event;
2217 
2218 	if (optlen > sizeof(struct sctp_event_subscribe))
2219 		return -EINVAL;
2220 	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
2221 		return -EFAULT;
2222 
2223 	/* At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT,
2224 	 * if there is no data to be sent or retransmit, the stack will
2225 	 * immediately send up this notification.
2226 	 */
2227 	if (sctp_ulpevent_type_enabled(SCTP_SENDER_DRY_EVENT,
2228 				       &sctp_sk(sk)->subscribe)) {
2229 		asoc = sctp_id2assoc(sk, 0);
2230 
2231 		if (asoc && sctp_outq_is_empty(&asoc->outqueue)) {
2232 			event = sctp_ulpevent_make_sender_dry_event(asoc,
2233 					GFP_ATOMIC);
2234 			if (!event)
2235 				return -ENOMEM;
2236 
2237 			sctp_ulpq_tail_event(&asoc->ulpq, event);
2238 		}
2239 	}
2240 
2241 	return 0;
2242 }
2243 
2244 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
2245  *
2246  * This socket option is applicable to the UDP-style socket only.  When
2247  * set it will cause associations that are idle for more than the
2248  * specified number of seconds to automatically close.  An association
2249  * being idle is defined an association that has NOT sent or received
2250  * user data.  The special value of '0' indicates that no automatic
2251  * close of any associations should be performed.  The option expects an
2252  * integer defining the number of seconds of idle time before an
2253  * association is closed.
2254  */
2255 static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
2256 				     unsigned int optlen)
2257 {
2258 	struct sctp_sock *sp = sctp_sk(sk);
2259 	struct net *net = sock_net(sk);
2260 
2261 	/* Applicable to UDP-style socket only */
2262 	if (sctp_style(sk, TCP))
2263 		return -EOPNOTSUPP;
2264 	if (optlen != sizeof(int))
2265 		return -EINVAL;
2266 	if (copy_from_user(&sp->autoclose, optval, optlen))
2267 		return -EFAULT;
2268 
2269 	if (sp->autoclose > net->sctp.max_autoclose)
2270 		sp->autoclose = net->sctp.max_autoclose;
2271 
2272 	return 0;
2273 }
2274 
2275 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
2276  *
2277  * Applications can enable or disable heartbeats for any peer address of
2278  * an association, modify an address's heartbeat interval, force a
2279  * heartbeat to be sent immediately, and adjust the address's maximum
2280  * number of retransmissions sent before an address is considered
2281  * unreachable.  The following structure is used to access and modify an
2282  * address's parameters:
2283  *
2284  *  struct sctp_paddrparams {
2285  *     sctp_assoc_t            spp_assoc_id;
2286  *     struct sockaddr_storage spp_address;
2287  *     uint32_t                spp_hbinterval;
2288  *     uint16_t                spp_pathmaxrxt;
2289  *     uint32_t                spp_pathmtu;
2290  *     uint32_t                spp_sackdelay;
2291  *     uint32_t                spp_flags;
2292  * };
2293  *
2294  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
2295  *                     application, and identifies the association for
2296  *                     this query.
2297  *   spp_address     - This specifies which address is of interest.
2298  *   spp_hbinterval  - This contains the value of the heartbeat interval,
2299  *                     in milliseconds.  If a  value of zero
2300  *                     is present in this field then no changes are to
2301  *                     be made to this parameter.
2302  *   spp_pathmaxrxt  - This contains the maximum number of
2303  *                     retransmissions before this address shall be
2304  *                     considered unreachable. If a  value of zero
2305  *                     is present in this field then no changes are to
2306  *                     be made to this parameter.
2307  *   spp_pathmtu     - When Path MTU discovery is disabled the value
2308  *                     specified here will be the "fixed" path mtu.
2309  *                     Note that if the spp_address field is empty
2310  *                     then all associations on this address will
2311  *                     have this fixed path mtu set upon them.
2312  *
2313  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
2314  *                     the number of milliseconds that sacks will be delayed
2315  *                     for. This value will apply to all addresses of an
2316  *                     association if the spp_address field is empty. Note
2317  *                     also, that if delayed sack is enabled and this
2318  *                     value is set to 0, no change is made to the last
2319  *                     recorded delayed sack timer value.
2320  *
2321  *   spp_flags       - These flags are used to control various features
2322  *                     on an association. The flag field may contain
2323  *                     zero or more of the following options.
2324  *
2325  *                     SPP_HB_ENABLE  - Enable heartbeats on the
2326  *                     specified address. Note that if the address
2327  *                     field is empty all addresses for the association
2328  *                     have heartbeats enabled upon them.
2329  *
2330  *                     SPP_HB_DISABLE - Disable heartbeats on the
2331  *                     speicifed address. Note that if the address
2332  *                     field is empty all addresses for the association
2333  *                     will have their heartbeats disabled. Note also
2334  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
2335  *                     mutually exclusive, only one of these two should
2336  *                     be specified. Enabling both fields will have
2337  *                     undetermined results.
2338  *
2339  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
2340  *                     to be made immediately.
2341  *
2342  *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
2343  *                     heartbeat delayis to be set to the value of 0
2344  *                     milliseconds.
2345  *
2346  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
2347  *                     discovery upon the specified address. Note that
2348  *                     if the address feild is empty then all addresses
2349  *                     on the association are effected.
2350  *
2351  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
2352  *                     discovery upon the specified address. Note that
2353  *                     if the address feild is empty then all addresses
2354  *                     on the association are effected. Not also that
2355  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
2356  *                     exclusive. Enabling both will have undetermined
2357  *                     results.
2358  *
2359  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
2360  *                     on delayed sack. The time specified in spp_sackdelay
2361  *                     is used to specify the sack delay for this address. Note
2362  *                     that if spp_address is empty then all addresses will
2363  *                     enable delayed sack and take on the sack delay
2364  *                     value specified in spp_sackdelay.
2365  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
2366  *                     off delayed sack. If the spp_address field is blank then
2367  *                     delayed sack is disabled for the entire association. Note
2368  *                     also that this field is mutually exclusive to
2369  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
2370  *                     results.
2371  */
2372 static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
2373 				       struct sctp_transport   *trans,
2374 				       struct sctp_association *asoc,
2375 				       struct sctp_sock        *sp,
2376 				       int                      hb_change,
2377 				       int                      pmtud_change,
2378 				       int                      sackdelay_change)
2379 {
2380 	int error;
2381 
2382 	if (params->spp_flags & SPP_HB_DEMAND && trans) {
2383 		struct net *net = sock_net(trans->asoc->base.sk);
2384 
2385 		error = sctp_primitive_REQUESTHEARTBEAT(net, trans->asoc, trans);
2386 		if (error)
2387 			return error;
2388 	}
2389 
2390 	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
2391 	 * this field is ignored.  Note also that a value of zero indicates
2392 	 * the current setting should be left unchanged.
2393 	 */
2394 	if (params->spp_flags & SPP_HB_ENABLE) {
2395 
2396 		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
2397 		 * set.  This lets us use 0 value when this flag
2398 		 * is set.
2399 		 */
2400 		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
2401 			params->spp_hbinterval = 0;
2402 
2403 		if (params->spp_hbinterval ||
2404 		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
2405 			if (trans) {
2406 				trans->hbinterval =
2407 				    msecs_to_jiffies(params->spp_hbinterval);
2408 			} else if (asoc) {
2409 				asoc->hbinterval =
2410 				    msecs_to_jiffies(params->spp_hbinterval);
2411 			} else {
2412 				sp->hbinterval = params->spp_hbinterval;
2413 			}
2414 		}
2415 	}
2416 
2417 	if (hb_change) {
2418 		if (trans) {
2419 			trans->param_flags =
2420 				(trans->param_flags & ~SPP_HB) | hb_change;
2421 		} else if (asoc) {
2422 			asoc->param_flags =
2423 				(asoc->param_flags & ~SPP_HB) | hb_change;
2424 		} else {
2425 			sp->param_flags =
2426 				(sp->param_flags & ~SPP_HB) | hb_change;
2427 		}
2428 	}
2429 
2430 	/* When Path MTU discovery is disabled the value specified here will
2431 	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
2432 	 * include the flag SPP_PMTUD_DISABLE for this field to have any
2433 	 * effect).
2434 	 */
2435 	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
2436 		if (trans) {
2437 			trans->pathmtu = params->spp_pathmtu;
2438 			sctp_assoc_sync_pmtu(asoc);
2439 		} else if (asoc) {
2440 			asoc->pathmtu = params->spp_pathmtu;
2441 		} else {
2442 			sp->pathmtu = params->spp_pathmtu;
2443 		}
2444 	}
2445 
2446 	if (pmtud_change) {
2447 		if (trans) {
2448 			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
2449 				(params->spp_flags & SPP_PMTUD_ENABLE);
2450 			trans->param_flags =
2451 				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
2452 			if (update) {
2453 				sctp_transport_pmtu(trans, sctp_opt2sk(sp));
2454 				sctp_assoc_sync_pmtu(asoc);
2455 			}
2456 		} else if (asoc) {
2457 			asoc->param_flags =
2458 				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
2459 		} else {
2460 			sp->param_flags =
2461 				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
2462 		}
2463 	}
2464 
2465 	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
2466 	 * value of this field is ignored.  Note also that a value of zero
2467 	 * indicates the current setting should be left unchanged.
2468 	 */
2469 	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
2470 		if (trans) {
2471 			trans->sackdelay =
2472 				msecs_to_jiffies(params->spp_sackdelay);
2473 		} else if (asoc) {
2474 			asoc->sackdelay =
2475 				msecs_to_jiffies(params->spp_sackdelay);
2476 		} else {
2477 			sp->sackdelay = params->spp_sackdelay;
2478 		}
2479 	}
2480 
2481 	if (sackdelay_change) {
2482 		if (trans) {
2483 			trans->param_flags =
2484 				(trans->param_flags & ~SPP_SACKDELAY) |
2485 				sackdelay_change;
2486 		} else if (asoc) {
2487 			asoc->param_flags =
2488 				(asoc->param_flags & ~SPP_SACKDELAY) |
2489 				sackdelay_change;
2490 		} else {
2491 			sp->param_flags =
2492 				(sp->param_flags & ~SPP_SACKDELAY) |
2493 				sackdelay_change;
2494 		}
2495 	}
2496 
2497 	/* Note that a value of zero indicates the current setting should be
2498 	   left unchanged.
2499 	 */
2500 	if (params->spp_pathmaxrxt) {
2501 		if (trans) {
2502 			trans->pathmaxrxt = params->spp_pathmaxrxt;
2503 		} else if (asoc) {
2504 			asoc->pathmaxrxt = params->spp_pathmaxrxt;
2505 		} else {
2506 			sp->pathmaxrxt = params->spp_pathmaxrxt;
2507 		}
2508 	}
2509 
2510 	return 0;
2511 }
2512 
2513 static int sctp_setsockopt_peer_addr_params(struct sock *sk,
2514 					    char __user *optval,
2515 					    unsigned int optlen)
2516 {
2517 	struct sctp_paddrparams  params;
2518 	struct sctp_transport   *trans = NULL;
2519 	struct sctp_association *asoc = NULL;
2520 	struct sctp_sock        *sp = sctp_sk(sk);
2521 	int error;
2522 	int hb_change, pmtud_change, sackdelay_change;
2523 
2524 	if (optlen != sizeof(struct sctp_paddrparams))
2525 		return -EINVAL;
2526 
2527 	if (copy_from_user(&params, optval, optlen))
2528 		return -EFAULT;
2529 
2530 	/* Validate flags and value parameters. */
2531 	hb_change        = params.spp_flags & SPP_HB;
2532 	pmtud_change     = params.spp_flags & SPP_PMTUD;
2533 	sackdelay_change = params.spp_flags & SPP_SACKDELAY;
2534 
2535 	if (hb_change        == SPP_HB ||
2536 	    pmtud_change     == SPP_PMTUD ||
2537 	    sackdelay_change == SPP_SACKDELAY ||
2538 	    params.spp_sackdelay > 500 ||
2539 	    (params.spp_pathmtu &&
2540 	     params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
2541 		return -EINVAL;
2542 
2543 	/* If an address other than INADDR_ANY is specified, and
2544 	 * no transport is found, then the request is invalid.
2545 	 */
2546 	if (!sctp_is_any(sk, (union sctp_addr *)&params.spp_address)) {
2547 		trans = sctp_addr_id2transport(sk, &params.spp_address,
2548 					       params.spp_assoc_id);
2549 		if (!trans)
2550 			return -EINVAL;
2551 	}
2552 
2553 	/* Get association, if assoc_id != 0 and the socket is a one
2554 	 * to many style socket, and an association was not found, then
2555 	 * the id was invalid.
2556 	 */
2557 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
2558 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
2559 		return -EINVAL;
2560 
2561 	/* Heartbeat demand can only be sent on a transport or
2562 	 * association, but not a socket.
2563 	 */
2564 	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
2565 		return -EINVAL;
2566 
2567 	/* Process parameters. */
2568 	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2569 					    hb_change, pmtud_change,
2570 					    sackdelay_change);
2571 
2572 	if (error)
2573 		return error;
2574 
2575 	/* If changes are for association, also apply parameters to each
2576 	 * transport.
2577 	 */
2578 	if (!trans && asoc) {
2579 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2580 				transports) {
2581 			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2582 						    hb_change, pmtud_change,
2583 						    sackdelay_change);
2584 		}
2585 	}
2586 
2587 	return 0;
2588 }
2589 
2590 static inline __u32 sctp_spp_sackdelay_enable(__u32 param_flags)
2591 {
2592 	return (param_flags & ~SPP_SACKDELAY) | SPP_SACKDELAY_ENABLE;
2593 }
2594 
2595 static inline __u32 sctp_spp_sackdelay_disable(__u32 param_flags)
2596 {
2597 	return (param_flags & ~SPP_SACKDELAY) | SPP_SACKDELAY_DISABLE;
2598 }
2599 
2600 /*
2601  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
2602  *
2603  * This option will effect the way delayed acks are performed.  This
2604  * option allows you to get or set the delayed ack time, in
2605  * milliseconds.  It also allows changing the delayed ack frequency.
2606  * Changing the frequency to 1 disables the delayed sack algorithm.  If
2607  * the assoc_id is 0, then this sets or gets the endpoints default
2608  * values.  If the assoc_id field is non-zero, then the set or get
2609  * effects the specified association for the one to many model (the
2610  * assoc_id field is ignored by the one to one model).  Note that if
2611  * sack_delay or sack_freq are 0 when setting this option, then the
2612  * current values will remain unchanged.
2613  *
2614  * struct sctp_sack_info {
2615  *     sctp_assoc_t            sack_assoc_id;
2616  *     uint32_t                sack_delay;
2617  *     uint32_t                sack_freq;
2618  * };
2619  *
2620  * sack_assoc_id -  This parameter, indicates which association the user
2621  *    is performing an action upon.  Note that if this field's value is
2622  *    zero then the endpoints default value is changed (effecting future
2623  *    associations only).
2624  *
2625  * sack_delay -  This parameter contains the number of milliseconds that
2626  *    the user is requesting the delayed ACK timer be set to.  Note that
2627  *    this value is defined in the standard to be between 200 and 500
2628  *    milliseconds.
2629  *
2630  * sack_freq -  This parameter contains the number of packets that must
2631  *    be received before a sack is sent without waiting for the delay
2632  *    timer to expire.  The default value for this is 2, setting this
2633  *    value to 1 will disable the delayed sack algorithm.
2634  */
2635 
2636 static int sctp_setsockopt_delayed_ack(struct sock *sk,
2637 				       char __user *optval, unsigned int optlen)
2638 {
2639 	struct sctp_sack_info    params;
2640 	struct sctp_transport   *trans = NULL;
2641 	struct sctp_association *asoc = NULL;
2642 	struct sctp_sock        *sp = sctp_sk(sk);
2643 
2644 	if (optlen == sizeof(struct sctp_sack_info)) {
2645 		if (copy_from_user(&params, optval, optlen))
2646 			return -EFAULT;
2647 
2648 		if (params.sack_delay == 0 && params.sack_freq == 0)
2649 			return 0;
2650 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
2651 		pr_warn_ratelimited(DEPRECATED
2652 				    "%s (pid %d) "
2653 				    "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
2654 				    "Use struct sctp_sack_info instead\n",
2655 				    current->comm, task_pid_nr(current));
2656 		if (copy_from_user(&params, optval, optlen))
2657 			return -EFAULT;
2658 
2659 		if (params.sack_delay == 0)
2660 			params.sack_freq = 1;
2661 		else
2662 			params.sack_freq = 0;
2663 	} else
2664 		return -EINVAL;
2665 
2666 	/* Validate value parameter. */
2667 	if (params.sack_delay > 500)
2668 		return -EINVAL;
2669 
2670 	/* Get association, if sack_assoc_id != 0 and the socket is a one
2671 	 * to many style socket, and an association was not found, then
2672 	 * the id was invalid.
2673 	 */
2674 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
2675 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
2676 		return -EINVAL;
2677 
2678 	if (params.sack_delay) {
2679 		if (asoc) {
2680 			asoc->sackdelay =
2681 				msecs_to_jiffies(params.sack_delay);
2682 			asoc->param_flags =
2683 				sctp_spp_sackdelay_enable(asoc->param_flags);
2684 		} else {
2685 			sp->sackdelay = params.sack_delay;
2686 			sp->param_flags =
2687 				sctp_spp_sackdelay_enable(sp->param_flags);
2688 		}
2689 	}
2690 
2691 	if (params.sack_freq == 1) {
2692 		if (asoc) {
2693 			asoc->param_flags =
2694 				sctp_spp_sackdelay_disable(asoc->param_flags);
2695 		} else {
2696 			sp->param_flags =
2697 				sctp_spp_sackdelay_disable(sp->param_flags);
2698 		}
2699 	} else if (params.sack_freq > 1) {
2700 		if (asoc) {
2701 			asoc->sackfreq = params.sack_freq;
2702 			asoc->param_flags =
2703 				sctp_spp_sackdelay_enable(asoc->param_flags);
2704 		} else {
2705 			sp->sackfreq = params.sack_freq;
2706 			sp->param_flags =
2707 				sctp_spp_sackdelay_enable(sp->param_flags);
2708 		}
2709 	}
2710 
2711 	/* If change is for association, also apply to each transport. */
2712 	if (asoc) {
2713 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2714 				transports) {
2715 			if (params.sack_delay) {
2716 				trans->sackdelay =
2717 					msecs_to_jiffies(params.sack_delay);
2718 				trans->param_flags =
2719 					sctp_spp_sackdelay_enable(trans->param_flags);
2720 			}
2721 			if (params.sack_freq == 1) {
2722 				trans->param_flags =
2723 					sctp_spp_sackdelay_disable(trans->param_flags);
2724 			} else if (params.sack_freq > 1) {
2725 				trans->sackfreq = params.sack_freq;
2726 				trans->param_flags =
2727 					sctp_spp_sackdelay_enable(trans->param_flags);
2728 			}
2729 		}
2730 	}
2731 
2732 	return 0;
2733 }
2734 
2735 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
2736  *
2737  * Applications can specify protocol parameters for the default association
2738  * initialization.  The option name argument to setsockopt() and getsockopt()
2739  * is SCTP_INITMSG.
2740  *
2741  * Setting initialization parameters is effective only on an unconnected
2742  * socket (for UDP-style sockets only future associations are effected
2743  * by the change).  With TCP-style sockets, this option is inherited by
2744  * sockets derived from a listener socket.
2745  */
2746 static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, unsigned int optlen)
2747 {
2748 	struct sctp_initmsg sinit;
2749 	struct sctp_sock *sp = sctp_sk(sk);
2750 
2751 	if (optlen != sizeof(struct sctp_initmsg))
2752 		return -EINVAL;
2753 	if (copy_from_user(&sinit, optval, optlen))
2754 		return -EFAULT;
2755 
2756 	if (sinit.sinit_num_ostreams)
2757 		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
2758 	if (sinit.sinit_max_instreams)
2759 		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
2760 	if (sinit.sinit_max_attempts)
2761 		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
2762 	if (sinit.sinit_max_init_timeo)
2763 		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
2764 
2765 	return 0;
2766 }
2767 
2768 /*
2769  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
2770  *
2771  *   Applications that wish to use the sendto() system call may wish to
2772  *   specify a default set of parameters that would normally be supplied
2773  *   through the inclusion of ancillary data.  This socket option allows
2774  *   such an application to set the default sctp_sndrcvinfo structure.
2775  *   The application that wishes to use this socket option simply passes
2776  *   in to this call the sctp_sndrcvinfo structure defined in Section
2777  *   5.2.2) The input parameters accepted by this call include
2778  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
2779  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
2780  *   to this call if the caller is using the UDP model.
2781  */
2782 static int sctp_setsockopt_default_send_param(struct sock *sk,
2783 					      char __user *optval,
2784 					      unsigned int optlen)
2785 {
2786 	struct sctp_sock *sp = sctp_sk(sk);
2787 	struct sctp_association *asoc;
2788 	struct sctp_sndrcvinfo info;
2789 
2790 	if (optlen != sizeof(info))
2791 		return -EINVAL;
2792 	if (copy_from_user(&info, optval, optlen))
2793 		return -EFAULT;
2794 	if (info.sinfo_flags &
2795 	    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
2796 	      SCTP_ABORT | SCTP_EOF))
2797 		return -EINVAL;
2798 
2799 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
2800 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
2801 		return -EINVAL;
2802 	if (asoc) {
2803 		asoc->default_stream = info.sinfo_stream;
2804 		asoc->default_flags = info.sinfo_flags;
2805 		asoc->default_ppid = info.sinfo_ppid;
2806 		asoc->default_context = info.sinfo_context;
2807 		asoc->default_timetolive = info.sinfo_timetolive;
2808 	} else {
2809 		sp->default_stream = info.sinfo_stream;
2810 		sp->default_flags = info.sinfo_flags;
2811 		sp->default_ppid = info.sinfo_ppid;
2812 		sp->default_context = info.sinfo_context;
2813 		sp->default_timetolive = info.sinfo_timetolive;
2814 	}
2815 
2816 	return 0;
2817 }
2818 
2819 /* RFC6458, Section 8.1.31. Set/get Default Send Parameters
2820  * (SCTP_DEFAULT_SNDINFO)
2821  */
2822 static int sctp_setsockopt_default_sndinfo(struct sock *sk,
2823 					   char __user *optval,
2824 					   unsigned int optlen)
2825 {
2826 	struct sctp_sock *sp = sctp_sk(sk);
2827 	struct sctp_association *asoc;
2828 	struct sctp_sndinfo info;
2829 
2830 	if (optlen != sizeof(info))
2831 		return -EINVAL;
2832 	if (copy_from_user(&info, optval, optlen))
2833 		return -EFAULT;
2834 	if (info.snd_flags &
2835 	    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
2836 	      SCTP_ABORT | SCTP_EOF))
2837 		return -EINVAL;
2838 
2839 	asoc = sctp_id2assoc(sk, info.snd_assoc_id);
2840 	if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
2841 		return -EINVAL;
2842 	if (asoc) {
2843 		asoc->default_stream = info.snd_sid;
2844 		asoc->default_flags = info.snd_flags;
2845 		asoc->default_ppid = info.snd_ppid;
2846 		asoc->default_context = info.snd_context;
2847 	} else {
2848 		sp->default_stream = info.snd_sid;
2849 		sp->default_flags = info.snd_flags;
2850 		sp->default_ppid = info.snd_ppid;
2851 		sp->default_context = info.snd_context;
2852 	}
2853 
2854 	return 0;
2855 }
2856 
2857 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
2858  *
2859  * Requests that the local SCTP stack use the enclosed peer address as
2860  * the association primary.  The enclosed address must be one of the
2861  * association peer's addresses.
2862  */
2863 static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
2864 					unsigned int optlen)
2865 {
2866 	struct sctp_prim prim;
2867 	struct sctp_transport *trans;
2868 
2869 	if (optlen != sizeof(struct sctp_prim))
2870 		return -EINVAL;
2871 
2872 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
2873 		return -EFAULT;
2874 
2875 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
2876 	if (!trans)
2877 		return -EINVAL;
2878 
2879 	sctp_assoc_set_primary(trans->asoc, trans);
2880 
2881 	return 0;
2882 }
2883 
2884 /*
2885  * 7.1.5 SCTP_NODELAY
2886  *
2887  * Turn on/off any Nagle-like algorithm.  This means that packets are
2888  * generally sent as soon as possible and no unnecessary delays are
2889  * introduced, at the cost of more packets in the network.  Expects an
2890  *  integer boolean flag.
2891  */
2892 static int sctp_setsockopt_nodelay(struct sock *sk, char __user *optval,
2893 				   unsigned int optlen)
2894 {
2895 	int val;
2896 
2897 	if (optlen < sizeof(int))
2898 		return -EINVAL;
2899 	if (get_user(val, (int __user *)optval))
2900 		return -EFAULT;
2901 
2902 	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
2903 	return 0;
2904 }
2905 
2906 /*
2907  *
2908  * 7.1.1 SCTP_RTOINFO
2909  *
2910  * The protocol parameters used to initialize and bound retransmission
2911  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
2912  * and modify these parameters.
2913  * All parameters are time values, in milliseconds.  A value of 0, when
2914  * modifying the parameters, indicates that the current value should not
2915  * be changed.
2916  *
2917  */
2918 static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, unsigned int optlen)
2919 {
2920 	struct sctp_rtoinfo rtoinfo;
2921 	struct sctp_association *asoc;
2922 	unsigned long rto_min, rto_max;
2923 	struct sctp_sock *sp = sctp_sk(sk);
2924 
2925 	if (optlen != sizeof (struct sctp_rtoinfo))
2926 		return -EINVAL;
2927 
2928 	if (copy_from_user(&rtoinfo, optval, optlen))
2929 		return -EFAULT;
2930 
2931 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
2932 
2933 	/* Set the values to the specific association */
2934 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
2935 		return -EINVAL;
2936 
2937 	rto_max = rtoinfo.srto_max;
2938 	rto_min = rtoinfo.srto_min;
2939 
2940 	if (rto_max)
2941 		rto_max = asoc ? msecs_to_jiffies(rto_max) : rto_max;
2942 	else
2943 		rto_max = asoc ? asoc->rto_max : sp->rtoinfo.srto_max;
2944 
2945 	if (rto_min)
2946 		rto_min = asoc ? msecs_to_jiffies(rto_min) : rto_min;
2947 	else
2948 		rto_min = asoc ? asoc->rto_min : sp->rtoinfo.srto_min;
2949 
2950 	if (rto_min > rto_max)
2951 		return -EINVAL;
2952 
2953 	if (asoc) {
2954 		if (rtoinfo.srto_initial != 0)
2955 			asoc->rto_initial =
2956 				msecs_to_jiffies(rtoinfo.srto_initial);
2957 		asoc->rto_max = rto_max;
2958 		asoc->rto_min = rto_min;
2959 	} else {
2960 		/* If there is no association or the association-id = 0
2961 		 * set the values to the endpoint.
2962 		 */
2963 		if (rtoinfo.srto_initial != 0)
2964 			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
2965 		sp->rtoinfo.srto_max = rto_max;
2966 		sp->rtoinfo.srto_min = rto_min;
2967 	}
2968 
2969 	return 0;
2970 }
2971 
2972 /*
2973  *
2974  * 7.1.2 SCTP_ASSOCINFO
2975  *
2976  * This option is used to tune the maximum retransmission attempts
2977  * of the association.
2978  * Returns an error if the new association retransmission value is
2979  * greater than the sum of the retransmission value  of the peer.
2980  * See [SCTP] for more information.
2981  *
2982  */
2983 static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, unsigned int optlen)
2984 {
2985 
2986 	struct sctp_assocparams assocparams;
2987 	struct sctp_association *asoc;
2988 
2989 	if (optlen != sizeof(struct sctp_assocparams))
2990 		return -EINVAL;
2991 	if (copy_from_user(&assocparams, optval, optlen))
2992 		return -EFAULT;
2993 
2994 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
2995 
2996 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
2997 		return -EINVAL;
2998 
2999 	/* Set the values to the specific association */
3000 	if (asoc) {
3001 		if (assocparams.sasoc_asocmaxrxt != 0) {
3002 			__u32 path_sum = 0;
3003 			int   paths = 0;
3004 			struct sctp_transport *peer_addr;
3005 
3006 			list_for_each_entry(peer_addr, &asoc->peer.transport_addr_list,
3007 					transports) {
3008 				path_sum += peer_addr->pathmaxrxt;
3009 				paths++;
3010 			}
3011 
3012 			/* Only validate asocmaxrxt if we have more than
3013 			 * one path/transport.  We do this because path
3014 			 * retransmissions are only counted when we have more
3015 			 * then one path.
3016 			 */
3017 			if (paths > 1 &&
3018 			    assocparams.sasoc_asocmaxrxt > path_sum)
3019 				return -EINVAL;
3020 
3021 			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
3022 		}
3023 
3024 		if (assocparams.sasoc_cookie_life != 0)
3025 			asoc->cookie_life = ms_to_ktime(assocparams.sasoc_cookie_life);
3026 	} else {
3027 		/* Set the values to the endpoint */
3028 		struct sctp_sock *sp = sctp_sk(sk);
3029 
3030 		if (assocparams.sasoc_asocmaxrxt != 0)
3031 			sp->assocparams.sasoc_asocmaxrxt =
3032 						assocparams.sasoc_asocmaxrxt;
3033 		if (assocparams.sasoc_cookie_life != 0)
3034 			sp->assocparams.sasoc_cookie_life =
3035 						assocparams.sasoc_cookie_life;
3036 	}
3037 	return 0;
3038 }
3039 
3040 /*
3041  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
3042  *
3043  * This socket option is a boolean flag which turns on or off mapped V4
3044  * addresses.  If this option is turned on and the socket is type
3045  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
3046  * If this option is turned off, then no mapping will be done of V4
3047  * addresses and a user will receive both PF_INET6 and PF_INET type
3048  * addresses on the socket.
3049  */
3050 static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsigned int optlen)
3051 {
3052 	int val;
3053 	struct sctp_sock *sp = sctp_sk(sk);
3054 
3055 	if (optlen < sizeof(int))
3056 		return -EINVAL;
3057 	if (get_user(val, (int __user *)optval))
3058 		return -EFAULT;
3059 	if (val)
3060 		sp->v4mapped = 1;
3061 	else
3062 		sp->v4mapped = 0;
3063 
3064 	return 0;
3065 }
3066 
3067 /*
3068  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
3069  * This option will get or set the maximum size to put in any outgoing
3070  * SCTP DATA chunk.  If a message is larger than this size it will be
3071  * fragmented by SCTP into the specified size.  Note that the underlying
3072  * SCTP implementation may fragment into smaller sized chunks when the
3073  * PMTU of the underlying association is smaller than the value set by
3074  * the user.  The default value for this option is '0' which indicates
3075  * the user is NOT limiting fragmentation and only the PMTU will effect
3076  * SCTP's choice of DATA chunk size.  Note also that values set larger
3077  * than the maximum size of an IP datagram will effectively let SCTP
3078  * control fragmentation (i.e. the same as setting this option to 0).
3079  *
3080  * The following structure is used to access and modify this parameter:
3081  *
3082  * struct sctp_assoc_value {
3083  *   sctp_assoc_t assoc_id;
3084  *   uint32_t assoc_value;
3085  * };
3086  *
3087  * assoc_id:  This parameter is ignored for one-to-one style sockets.
3088  *    For one-to-many style sockets this parameter indicates which
3089  *    association the user is performing an action upon.  Note that if
3090  *    this field's value is zero then the endpoints default value is
3091  *    changed (effecting future associations only).
3092  * assoc_value:  This parameter specifies the maximum size in bytes.
3093  */
3094 static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
3095 {
3096 	struct sctp_assoc_value params;
3097 	struct sctp_association *asoc;
3098 	struct sctp_sock *sp = sctp_sk(sk);
3099 	int val;
3100 
3101 	if (optlen == sizeof(int)) {
3102 		pr_warn_ratelimited(DEPRECATED
3103 				    "%s (pid %d) "
3104 				    "Use of int in maxseg socket option.\n"
3105 				    "Use struct sctp_assoc_value instead\n",
3106 				    current->comm, task_pid_nr(current));
3107 		if (copy_from_user(&val, optval, optlen))
3108 			return -EFAULT;
3109 		params.assoc_id = 0;
3110 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
3111 		if (copy_from_user(&params, optval, optlen))
3112 			return -EFAULT;
3113 		val = params.assoc_value;
3114 	} else
3115 		return -EINVAL;
3116 
3117 	if ((val != 0) && ((val < 8) || (val > SCTP_MAX_CHUNK_LEN)))
3118 		return -EINVAL;
3119 
3120 	asoc = sctp_id2assoc(sk, params.assoc_id);
3121 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
3122 		return -EINVAL;
3123 
3124 	if (asoc) {
3125 		if (val == 0) {
3126 			val = asoc->pathmtu;
3127 			val -= sp->pf->af->net_header_len;
3128 			val -= sizeof(struct sctphdr) +
3129 					sizeof(struct sctp_data_chunk);
3130 		}
3131 		asoc->user_frag = val;
3132 		asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
3133 	} else {
3134 		sp->user_frag = val;
3135 	}
3136 
3137 	return 0;
3138 }
3139 
3140 
3141 /*
3142  *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
3143  *
3144  *   Requests that the peer mark the enclosed address as the association
3145  *   primary. The enclosed address must be one of the association's
3146  *   locally bound addresses. The following structure is used to make a
3147  *   set primary request:
3148  */
3149 static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
3150 					     unsigned int optlen)
3151 {
3152 	struct net *net = sock_net(sk);
3153 	struct sctp_sock	*sp;
3154 	struct sctp_association	*asoc = NULL;
3155 	struct sctp_setpeerprim	prim;
3156 	struct sctp_chunk	*chunk;
3157 	struct sctp_af		*af;
3158 	int 			err;
3159 
3160 	sp = sctp_sk(sk);
3161 
3162 	if (!net->sctp.addip_enable)
3163 		return -EPERM;
3164 
3165 	if (optlen != sizeof(struct sctp_setpeerprim))
3166 		return -EINVAL;
3167 
3168 	if (copy_from_user(&prim, optval, optlen))
3169 		return -EFAULT;
3170 
3171 	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
3172 	if (!asoc)
3173 		return -EINVAL;
3174 
3175 	if (!asoc->peer.asconf_capable)
3176 		return -EPERM;
3177 
3178 	if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
3179 		return -EPERM;
3180 
3181 	if (!sctp_state(asoc, ESTABLISHED))
3182 		return -ENOTCONN;
3183 
3184 	af = sctp_get_af_specific(prim.sspp_addr.ss_family);
3185 	if (!af)
3186 		return -EINVAL;
3187 
3188 	if (!af->addr_valid((union sctp_addr *)&prim.sspp_addr, sp, NULL))
3189 		return -EADDRNOTAVAIL;
3190 
3191 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
3192 		return -EADDRNOTAVAIL;
3193 
3194 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
3195 	chunk = sctp_make_asconf_set_prim(asoc,
3196 					  (union sctp_addr *)&prim.sspp_addr);
3197 	if (!chunk)
3198 		return -ENOMEM;
3199 
3200 	err = sctp_send_asconf(asoc, chunk);
3201 
3202 	pr_debug("%s: we set peer primary addr primitively\n", __func__);
3203 
3204 	return err;
3205 }
3206 
3207 static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
3208 					    unsigned int optlen)
3209 {
3210 	struct sctp_setadaptation adaptation;
3211 
3212 	if (optlen != sizeof(struct sctp_setadaptation))
3213 		return -EINVAL;
3214 	if (copy_from_user(&adaptation, optval, optlen))
3215 		return -EFAULT;
3216 
3217 	sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
3218 
3219 	return 0;
3220 }
3221 
3222 /*
3223  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
3224  *
3225  * The context field in the sctp_sndrcvinfo structure is normally only
3226  * used when a failed message is retrieved holding the value that was
3227  * sent down on the actual send call.  This option allows the setting of
3228  * a default context on an association basis that will be received on
3229  * reading messages from the peer.  This is especially helpful in the
3230  * one-2-many model for an application to keep some reference to an
3231  * internal state machine that is processing messages on the
3232  * association.  Note that the setting of this value only effects
3233  * received messages from the peer and does not effect the value that is
3234  * saved with outbound messages.
3235  */
3236 static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
3237 				   unsigned int optlen)
3238 {
3239 	struct sctp_assoc_value params;
3240 	struct sctp_sock *sp;
3241 	struct sctp_association *asoc;
3242 
3243 	if (optlen != sizeof(struct sctp_assoc_value))
3244 		return -EINVAL;
3245 	if (copy_from_user(&params, optval, optlen))
3246 		return -EFAULT;
3247 
3248 	sp = sctp_sk(sk);
3249 
3250 	if (params.assoc_id != 0) {
3251 		asoc = sctp_id2assoc(sk, params.assoc_id);
3252 		if (!asoc)
3253 			return -EINVAL;
3254 		asoc->default_rcv_context = params.assoc_value;
3255 	} else {
3256 		sp->default_rcv_context = params.assoc_value;
3257 	}
3258 
3259 	return 0;
3260 }
3261 
3262 /*
3263  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
3264  *
3265  * This options will at a minimum specify if the implementation is doing
3266  * fragmented interleave.  Fragmented interleave, for a one to many
3267  * socket, is when subsequent calls to receive a message may return
3268  * parts of messages from different associations.  Some implementations
3269  * may allow you to turn this value on or off.  If so, when turned off,
3270  * no fragment interleave will occur (which will cause a head of line
3271  * blocking amongst multiple associations sharing the same one to many
3272  * socket).  When this option is turned on, then each receive call may
3273  * come from a different association (thus the user must receive data
3274  * with the extended calls (e.g. sctp_recvmsg) to keep track of which
3275  * association each receive belongs to.
3276  *
3277  * This option takes a boolean value.  A non-zero value indicates that
3278  * fragmented interleave is on.  A value of zero indicates that
3279  * fragmented interleave is off.
3280  *
3281  * Note that it is important that an implementation that allows this
3282  * option to be turned on, have it off by default.  Otherwise an unaware
3283  * application using the one to many model may become confused and act
3284  * incorrectly.
3285  */
3286 static int sctp_setsockopt_fragment_interleave(struct sock *sk,
3287 					       char __user *optval,
3288 					       unsigned int optlen)
3289 {
3290 	int val;
3291 
3292 	if (optlen != sizeof(int))
3293 		return -EINVAL;
3294 	if (get_user(val, (int __user *)optval))
3295 		return -EFAULT;
3296 
3297 	sctp_sk(sk)->frag_interleave = (val == 0) ? 0 : 1;
3298 
3299 	return 0;
3300 }
3301 
3302 /*
3303  * 8.1.21.  Set or Get the SCTP Partial Delivery Point
3304  *       (SCTP_PARTIAL_DELIVERY_POINT)
3305  *
3306  * This option will set or get the SCTP partial delivery point.  This
3307  * point is the size of a message where the partial delivery API will be
3308  * invoked to help free up rwnd space for the peer.  Setting this to a
3309  * lower value will cause partial deliveries to happen more often.  The
3310  * calls argument is an integer that sets or gets the partial delivery
3311  * point.  Note also that the call will fail if the user attempts to set
3312  * this value larger than the socket receive buffer size.
3313  *
3314  * Note that any single message having a length smaller than or equal to
3315  * the SCTP partial delivery point will be delivered in one single read
3316  * call as long as the user provided buffer is large enough to hold the
3317  * message.
3318  */
3319 static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
3320 						  char __user *optval,
3321 						  unsigned int optlen)
3322 {
3323 	u32 val;
3324 
3325 	if (optlen != sizeof(u32))
3326 		return -EINVAL;
3327 	if (get_user(val, (int __user *)optval))
3328 		return -EFAULT;
3329 
3330 	/* Note: We double the receive buffer from what the user sets
3331 	 * it to be, also initial rwnd is based on rcvbuf/2.
3332 	 */
3333 	if (val > (sk->sk_rcvbuf >> 1))
3334 		return -EINVAL;
3335 
3336 	sctp_sk(sk)->pd_point = val;
3337 
3338 	return 0; /* is this the right error code? */
3339 }
3340 
3341 /*
3342  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
3343  *
3344  * This option will allow a user to change the maximum burst of packets
3345  * that can be emitted by this association.  Note that the default value
3346  * is 4, and some implementations may restrict this setting so that it
3347  * can only be lowered.
3348  *
3349  * NOTE: This text doesn't seem right.  Do this on a socket basis with
3350  * future associations inheriting the socket value.
3351  */
3352 static int sctp_setsockopt_maxburst(struct sock *sk,
3353 				    char __user *optval,
3354 				    unsigned int optlen)
3355 {
3356 	struct sctp_assoc_value params;
3357 	struct sctp_sock *sp;
3358 	struct sctp_association *asoc;
3359 	int val;
3360 	int assoc_id = 0;
3361 
3362 	if (optlen == sizeof(int)) {
3363 		pr_warn_ratelimited(DEPRECATED
3364 				    "%s (pid %d) "
3365 				    "Use of int in max_burst socket option deprecated.\n"
3366 				    "Use struct sctp_assoc_value instead\n",
3367 				    current->comm, task_pid_nr(current));
3368 		if (copy_from_user(&val, optval, optlen))
3369 			return -EFAULT;
3370 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
3371 		if (copy_from_user(&params, optval, optlen))
3372 			return -EFAULT;
3373 		val = params.assoc_value;
3374 		assoc_id = params.assoc_id;
3375 	} else
3376 		return -EINVAL;
3377 
3378 	sp = sctp_sk(sk);
3379 
3380 	if (assoc_id != 0) {
3381 		asoc = sctp_id2assoc(sk, assoc_id);
3382 		if (!asoc)
3383 			return -EINVAL;
3384 		asoc->max_burst = val;
3385 	} else
3386 		sp->max_burst = val;
3387 
3388 	return 0;
3389 }
3390 
3391 /*
3392  * 7.1.18.  Add a chunk that must be authenticated (SCTP_AUTH_CHUNK)
3393  *
3394  * This set option adds a chunk type that the user is requesting to be
3395  * received only in an authenticated way.  Changes to the list of chunks
3396  * will only effect future associations on the socket.
3397  */
3398 static int sctp_setsockopt_auth_chunk(struct sock *sk,
3399 				      char __user *optval,
3400 				      unsigned int optlen)
3401 {
3402 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3403 	struct sctp_authchunk val;
3404 
3405 	if (!ep->auth_enable)
3406 		return -EACCES;
3407 
3408 	if (optlen != sizeof(struct sctp_authchunk))
3409 		return -EINVAL;
3410 	if (copy_from_user(&val, optval, optlen))
3411 		return -EFAULT;
3412 
3413 	switch (val.sauth_chunk) {
3414 	case SCTP_CID_INIT:
3415 	case SCTP_CID_INIT_ACK:
3416 	case SCTP_CID_SHUTDOWN_COMPLETE:
3417 	case SCTP_CID_AUTH:
3418 		return -EINVAL;
3419 	}
3420 
3421 	/* add this chunk id to the endpoint */
3422 	return sctp_auth_ep_add_chunkid(ep, val.sauth_chunk);
3423 }
3424 
3425 /*
3426  * 7.1.19.  Get or set the list of supported HMAC Identifiers (SCTP_HMAC_IDENT)
3427  *
3428  * This option gets or sets the list of HMAC algorithms that the local
3429  * endpoint requires the peer to use.
3430  */
3431 static int sctp_setsockopt_hmac_ident(struct sock *sk,
3432 				      char __user *optval,
3433 				      unsigned int optlen)
3434 {
3435 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3436 	struct sctp_hmacalgo *hmacs;
3437 	u32 idents;
3438 	int err;
3439 
3440 	if (!ep->auth_enable)
3441 		return -EACCES;
3442 
3443 	if (optlen < sizeof(struct sctp_hmacalgo))
3444 		return -EINVAL;
3445 
3446 	hmacs = memdup_user(optval, optlen);
3447 	if (IS_ERR(hmacs))
3448 		return PTR_ERR(hmacs);
3449 
3450 	idents = hmacs->shmac_num_idents;
3451 	if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS ||
3452 	    (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo))) {
3453 		err = -EINVAL;
3454 		goto out;
3455 	}
3456 
3457 	err = sctp_auth_ep_set_hmacs(ep, hmacs);
3458 out:
3459 	kfree(hmacs);
3460 	return err;
3461 }
3462 
3463 /*
3464  * 7.1.20.  Set a shared key (SCTP_AUTH_KEY)
3465  *
3466  * This option will set a shared secret key which is used to build an
3467  * association shared key.
3468  */
3469 static int sctp_setsockopt_auth_key(struct sock *sk,
3470 				    char __user *optval,
3471 				    unsigned int optlen)
3472 {
3473 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3474 	struct sctp_authkey *authkey;
3475 	struct sctp_association *asoc;
3476 	int ret;
3477 
3478 	if (!ep->auth_enable)
3479 		return -EACCES;
3480 
3481 	if (optlen <= sizeof(struct sctp_authkey))
3482 		return -EINVAL;
3483 
3484 	authkey = memdup_user(optval, optlen);
3485 	if (IS_ERR(authkey))
3486 		return PTR_ERR(authkey);
3487 
3488 	if (authkey->sca_keylength > optlen - sizeof(struct sctp_authkey)) {
3489 		ret = -EINVAL;
3490 		goto out;
3491 	}
3492 
3493 	asoc = sctp_id2assoc(sk, authkey->sca_assoc_id);
3494 	if (!asoc && authkey->sca_assoc_id && sctp_style(sk, UDP)) {
3495 		ret = -EINVAL;
3496 		goto out;
3497 	}
3498 
3499 	ret = sctp_auth_set_key(ep, asoc, authkey);
3500 out:
3501 	kzfree(authkey);
3502 	return ret;
3503 }
3504 
3505 /*
3506  * 7.1.21.  Get or set the active shared key (SCTP_AUTH_ACTIVE_KEY)
3507  *
3508  * This option will get or set the active shared key to be used to build
3509  * the association shared key.
3510  */
3511 static int sctp_setsockopt_active_key(struct sock *sk,
3512 				      char __user *optval,
3513 				      unsigned int optlen)
3514 {
3515 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3516 	struct sctp_authkeyid val;
3517 	struct sctp_association *asoc;
3518 
3519 	if (!ep->auth_enable)
3520 		return -EACCES;
3521 
3522 	if (optlen != sizeof(struct sctp_authkeyid))
3523 		return -EINVAL;
3524 	if (copy_from_user(&val, optval, optlen))
3525 		return -EFAULT;
3526 
3527 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3528 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3529 		return -EINVAL;
3530 
3531 	return sctp_auth_set_active_key(ep, asoc, val.scact_keynumber);
3532 }
3533 
3534 /*
3535  * 7.1.22.  Delete a shared key (SCTP_AUTH_DELETE_KEY)
3536  *
3537  * This set option will delete a shared secret key from use.
3538  */
3539 static int sctp_setsockopt_del_key(struct sock *sk,
3540 				   char __user *optval,
3541 				   unsigned int optlen)
3542 {
3543 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3544 	struct sctp_authkeyid val;
3545 	struct sctp_association *asoc;
3546 
3547 	if (!ep->auth_enable)
3548 		return -EACCES;
3549 
3550 	if (optlen != sizeof(struct sctp_authkeyid))
3551 		return -EINVAL;
3552 	if (copy_from_user(&val, optval, optlen))
3553 		return -EFAULT;
3554 
3555 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3556 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3557 		return -EINVAL;
3558 
3559 	return sctp_auth_del_key_id(ep, asoc, val.scact_keynumber);
3560 
3561 }
3562 
3563 /*
3564  * 8.1.23 SCTP_AUTO_ASCONF
3565  *
3566  * This option will enable or disable the use of the automatic generation of
3567  * ASCONF chunks to add and delete addresses to an existing association.  Note
3568  * that this option has two caveats namely: a) it only affects sockets that
3569  * are bound to all addresses available to the SCTP stack, and b) the system
3570  * administrator may have an overriding control that turns the ASCONF feature
3571  * off no matter what setting the socket option may have.
3572  * This option expects an integer boolean flag, where a non-zero value turns on
3573  * the option, and a zero value turns off the option.
3574  * Note. In this implementation, socket operation overrides default parameter
3575  * being set by sysctl as well as FreeBSD implementation
3576  */
3577 static int sctp_setsockopt_auto_asconf(struct sock *sk, char __user *optval,
3578 					unsigned int optlen)
3579 {
3580 	int val;
3581 	struct sctp_sock *sp = sctp_sk(sk);
3582 
3583 	if (optlen < sizeof(int))
3584 		return -EINVAL;
3585 	if (get_user(val, (int __user *)optval))
3586 		return -EFAULT;
3587 	if (!sctp_is_ep_boundall(sk) && val)
3588 		return -EINVAL;
3589 	if ((val && sp->do_auto_asconf) || (!val && !sp->do_auto_asconf))
3590 		return 0;
3591 
3592 	spin_lock_bh(&sock_net(sk)->sctp.addr_wq_lock);
3593 	if (val == 0 && sp->do_auto_asconf) {
3594 		list_del(&sp->auto_asconf_list);
3595 		sp->do_auto_asconf = 0;
3596 	} else if (val && !sp->do_auto_asconf) {
3597 		list_add_tail(&sp->auto_asconf_list,
3598 		    &sock_net(sk)->sctp.auto_asconf_splist);
3599 		sp->do_auto_asconf = 1;
3600 	}
3601 	spin_unlock_bh(&sock_net(sk)->sctp.addr_wq_lock);
3602 	return 0;
3603 }
3604 
3605 /*
3606  * SCTP_PEER_ADDR_THLDS
3607  *
3608  * This option allows us to alter the partially failed threshold for one or all
3609  * transports in an association.  See Section 6.1 of:
3610  * http://www.ietf.org/id/draft-nishida-tsvwg-sctp-failover-05.txt
3611  */
3612 static int sctp_setsockopt_paddr_thresholds(struct sock *sk,
3613 					    char __user *optval,
3614 					    unsigned int optlen)
3615 {
3616 	struct sctp_paddrthlds val;
3617 	struct sctp_transport *trans;
3618 	struct sctp_association *asoc;
3619 
3620 	if (optlen < sizeof(struct sctp_paddrthlds))
3621 		return -EINVAL;
3622 	if (copy_from_user(&val, (struct sctp_paddrthlds __user *)optval,
3623 			   sizeof(struct sctp_paddrthlds)))
3624 		return -EFAULT;
3625 
3626 
3627 	if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
3628 		asoc = sctp_id2assoc(sk, val.spt_assoc_id);
3629 		if (!asoc)
3630 			return -ENOENT;
3631 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
3632 				    transports) {
3633 			if (val.spt_pathmaxrxt)
3634 				trans->pathmaxrxt = val.spt_pathmaxrxt;
3635 			trans->pf_retrans = val.spt_pathpfthld;
3636 		}
3637 
3638 		if (val.spt_pathmaxrxt)
3639 			asoc->pathmaxrxt = val.spt_pathmaxrxt;
3640 		asoc->pf_retrans = val.spt_pathpfthld;
3641 	} else {
3642 		trans = sctp_addr_id2transport(sk, &val.spt_address,
3643 					       val.spt_assoc_id);
3644 		if (!trans)
3645 			return -ENOENT;
3646 
3647 		if (val.spt_pathmaxrxt)
3648 			trans->pathmaxrxt = val.spt_pathmaxrxt;
3649 		trans->pf_retrans = val.spt_pathpfthld;
3650 	}
3651 
3652 	return 0;
3653 }
3654 
3655 static int sctp_setsockopt_recvrcvinfo(struct sock *sk,
3656 				       char __user *optval,
3657 				       unsigned int optlen)
3658 {
3659 	int val;
3660 
3661 	if (optlen < sizeof(int))
3662 		return -EINVAL;
3663 	if (get_user(val, (int __user *) optval))
3664 		return -EFAULT;
3665 
3666 	sctp_sk(sk)->recvrcvinfo = (val == 0) ? 0 : 1;
3667 
3668 	return 0;
3669 }
3670 
3671 static int sctp_setsockopt_recvnxtinfo(struct sock *sk,
3672 				       char __user *optval,
3673 				       unsigned int optlen)
3674 {
3675 	int val;
3676 
3677 	if (optlen < sizeof(int))
3678 		return -EINVAL;
3679 	if (get_user(val, (int __user *) optval))
3680 		return -EFAULT;
3681 
3682 	sctp_sk(sk)->recvnxtinfo = (val == 0) ? 0 : 1;
3683 
3684 	return 0;
3685 }
3686 
3687 static int sctp_setsockopt_pr_supported(struct sock *sk,
3688 					char __user *optval,
3689 					unsigned int optlen)
3690 {
3691 	struct sctp_assoc_value params;
3692 	struct sctp_association *asoc;
3693 	int retval = -EINVAL;
3694 
3695 	if (optlen != sizeof(params))
3696 		goto out;
3697 
3698 	if (copy_from_user(&params, optval, optlen)) {
3699 		retval = -EFAULT;
3700 		goto out;
3701 	}
3702 
3703 	asoc = sctp_id2assoc(sk, params.assoc_id);
3704 	if (asoc) {
3705 		asoc->prsctp_enable = !!params.assoc_value;
3706 	} else if (!params.assoc_id) {
3707 		struct sctp_sock *sp = sctp_sk(sk);
3708 
3709 		sp->ep->prsctp_enable = !!params.assoc_value;
3710 	} else {
3711 		goto out;
3712 	}
3713 
3714 	retval = 0;
3715 
3716 out:
3717 	return retval;
3718 }
3719 
3720 static int sctp_setsockopt_default_prinfo(struct sock *sk,
3721 					  char __user *optval,
3722 					  unsigned int optlen)
3723 {
3724 	struct sctp_default_prinfo info;
3725 	struct sctp_association *asoc;
3726 	int retval = -EINVAL;
3727 
3728 	if (optlen != sizeof(info))
3729 		goto out;
3730 
3731 	if (copy_from_user(&info, optval, sizeof(info))) {
3732 		retval = -EFAULT;
3733 		goto out;
3734 	}
3735 
3736 	if (info.pr_policy & ~SCTP_PR_SCTP_MASK)
3737 		goto out;
3738 
3739 	if (info.pr_policy == SCTP_PR_SCTP_NONE)
3740 		info.pr_value = 0;
3741 
3742 	asoc = sctp_id2assoc(sk, info.pr_assoc_id);
3743 	if (asoc) {
3744 		SCTP_PR_SET_POLICY(asoc->default_flags, info.pr_policy);
3745 		asoc->default_timetolive = info.pr_value;
3746 	} else if (!info.pr_assoc_id) {
3747 		struct sctp_sock *sp = sctp_sk(sk);
3748 
3749 		SCTP_PR_SET_POLICY(sp->default_flags, info.pr_policy);
3750 		sp->default_timetolive = info.pr_value;
3751 	} else {
3752 		goto out;
3753 	}
3754 
3755 	retval = 0;
3756 
3757 out:
3758 	return retval;
3759 }
3760 
3761 static int sctp_setsockopt_reconfig_supported(struct sock *sk,
3762 					      char __user *optval,
3763 					      unsigned int optlen)
3764 {
3765 	struct sctp_assoc_value params;
3766 	struct sctp_association *asoc;
3767 	int retval = -EINVAL;
3768 
3769 	if (optlen != sizeof(params))
3770 		goto out;
3771 
3772 	if (copy_from_user(&params, optval, optlen)) {
3773 		retval = -EFAULT;
3774 		goto out;
3775 	}
3776 
3777 	asoc = sctp_id2assoc(sk, params.assoc_id);
3778 	if (asoc) {
3779 		asoc->reconf_enable = !!params.assoc_value;
3780 	} else if (!params.assoc_id) {
3781 		struct sctp_sock *sp = sctp_sk(sk);
3782 
3783 		sp->ep->reconf_enable = !!params.assoc_value;
3784 	} else {
3785 		goto out;
3786 	}
3787 
3788 	retval = 0;
3789 
3790 out:
3791 	return retval;
3792 }
3793 
3794 static int sctp_setsockopt_enable_strreset(struct sock *sk,
3795 					   char __user *optval,
3796 					   unsigned int optlen)
3797 {
3798 	struct sctp_assoc_value params;
3799 	struct sctp_association *asoc;
3800 	int retval = -EINVAL;
3801 
3802 	if (optlen != sizeof(params))
3803 		goto out;
3804 
3805 	if (copy_from_user(&params, optval, optlen)) {
3806 		retval = -EFAULT;
3807 		goto out;
3808 	}
3809 
3810 	if (params.assoc_value & (~SCTP_ENABLE_STRRESET_MASK))
3811 		goto out;
3812 
3813 	asoc = sctp_id2assoc(sk, params.assoc_id);
3814 	if (asoc) {
3815 		asoc->strreset_enable = params.assoc_value;
3816 	} else if (!params.assoc_id) {
3817 		struct sctp_sock *sp = sctp_sk(sk);
3818 
3819 		sp->ep->strreset_enable = params.assoc_value;
3820 	} else {
3821 		goto out;
3822 	}
3823 
3824 	retval = 0;
3825 
3826 out:
3827 	return retval;
3828 }
3829 
3830 static int sctp_setsockopt_reset_streams(struct sock *sk,
3831 					 char __user *optval,
3832 					 unsigned int optlen)
3833 {
3834 	struct sctp_reset_streams *params;
3835 	struct sctp_association *asoc;
3836 	int retval = -EINVAL;
3837 
3838 	if (optlen < sizeof(struct sctp_reset_streams))
3839 		return -EINVAL;
3840 
3841 	params = memdup_user(optval, optlen);
3842 	if (IS_ERR(params))
3843 		return PTR_ERR(params);
3844 
3845 	asoc = sctp_id2assoc(sk, params->srs_assoc_id);
3846 	if (!asoc)
3847 		goto out;
3848 
3849 	retval = sctp_send_reset_streams(asoc, params);
3850 
3851 out:
3852 	kfree(params);
3853 	return retval;
3854 }
3855 
3856 static int sctp_setsockopt_reset_assoc(struct sock *sk,
3857 				       char __user *optval,
3858 				       unsigned int optlen)
3859 {
3860 	struct sctp_association *asoc;
3861 	sctp_assoc_t associd;
3862 	int retval = -EINVAL;
3863 
3864 	if (optlen != sizeof(associd))
3865 		goto out;
3866 
3867 	if (copy_from_user(&associd, optval, optlen)) {
3868 		retval = -EFAULT;
3869 		goto out;
3870 	}
3871 
3872 	asoc = sctp_id2assoc(sk, associd);
3873 	if (!asoc)
3874 		goto out;
3875 
3876 	retval = sctp_send_reset_assoc(asoc);
3877 
3878 out:
3879 	return retval;
3880 }
3881 
3882 static int sctp_setsockopt_add_streams(struct sock *sk,
3883 				       char __user *optval,
3884 				       unsigned int optlen)
3885 {
3886 	struct sctp_association *asoc;
3887 	struct sctp_add_streams params;
3888 	int retval = -EINVAL;
3889 
3890 	if (optlen != sizeof(params))
3891 		goto out;
3892 
3893 	if (copy_from_user(&params, optval, optlen)) {
3894 		retval = -EFAULT;
3895 		goto out;
3896 	}
3897 
3898 	asoc = sctp_id2assoc(sk, params.sas_assoc_id);
3899 	if (!asoc)
3900 		goto out;
3901 
3902 	retval = sctp_send_add_streams(asoc, &params);
3903 
3904 out:
3905 	return retval;
3906 }
3907 
3908 /* API 6.2 setsockopt(), getsockopt()
3909  *
3910  * Applications use setsockopt() and getsockopt() to set or retrieve
3911  * socket options.  Socket options are used to change the default
3912  * behavior of sockets calls.  They are described in Section 7.
3913  *
3914  * The syntax is:
3915  *
3916  *   ret = getsockopt(int sd, int level, int optname, void __user *optval,
3917  *                    int __user *optlen);
3918  *   ret = setsockopt(int sd, int level, int optname, const void __user *optval,
3919  *                    int optlen);
3920  *
3921  *   sd      - the socket descript.
3922  *   level   - set to IPPROTO_SCTP for all SCTP options.
3923  *   optname - the option name.
3924  *   optval  - the buffer to store the value of the option.
3925  *   optlen  - the size of the buffer.
3926  */
3927 static int sctp_setsockopt(struct sock *sk, int level, int optname,
3928 			   char __user *optval, unsigned int optlen)
3929 {
3930 	int retval = 0;
3931 
3932 	pr_debug("%s: sk:%p, optname:%d\n", __func__, sk, optname);
3933 
3934 	/* I can hardly begin to describe how wrong this is.  This is
3935 	 * so broken as to be worse than useless.  The API draft
3936 	 * REALLY is NOT helpful here...  I am not convinced that the
3937 	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
3938 	 * are at all well-founded.
3939 	 */
3940 	if (level != SOL_SCTP) {
3941 		struct sctp_af *af = sctp_sk(sk)->pf->af;
3942 		retval = af->setsockopt(sk, level, optname, optval, optlen);
3943 		goto out_nounlock;
3944 	}
3945 
3946 	lock_sock(sk);
3947 
3948 	switch (optname) {
3949 	case SCTP_SOCKOPT_BINDX_ADD:
3950 		/* 'optlen' is the size of the addresses buffer. */
3951 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3952 					       optlen, SCTP_BINDX_ADD_ADDR);
3953 		break;
3954 
3955 	case SCTP_SOCKOPT_BINDX_REM:
3956 		/* 'optlen' is the size of the addresses buffer. */
3957 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3958 					       optlen, SCTP_BINDX_REM_ADDR);
3959 		break;
3960 
3961 	case SCTP_SOCKOPT_CONNECTX_OLD:
3962 		/* 'optlen' is the size of the addresses buffer. */
3963 		retval = sctp_setsockopt_connectx_old(sk,
3964 					    (struct sockaddr __user *)optval,
3965 					    optlen);
3966 		break;
3967 
3968 	case SCTP_SOCKOPT_CONNECTX:
3969 		/* 'optlen' is the size of the addresses buffer. */
3970 		retval = sctp_setsockopt_connectx(sk,
3971 					    (struct sockaddr __user *)optval,
3972 					    optlen);
3973 		break;
3974 
3975 	case SCTP_DISABLE_FRAGMENTS:
3976 		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
3977 		break;
3978 
3979 	case SCTP_EVENTS:
3980 		retval = sctp_setsockopt_events(sk, optval, optlen);
3981 		break;
3982 
3983 	case SCTP_AUTOCLOSE:
3984 		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
3985 		break;
3986 
3987 	case SCTP_PEER_ADDR_PARAMS:
3988 		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
3989 		break;
3990 
3991 	case SCTP_DELAYED_SACK:
3992 		retval = sctp_setsockopt_delayed_ack(sk, optval, optlen);
3993 		break;
3994 	case SCTP_PARTIAL_DELIVERY_POINT:
3995 		retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
3996 		break;
3997 
3998 	case SCTP_INITMSG:
3999 		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
4000 		break;
4001 	case SCTP_DEFAULT_SEND_PARAM:
4002 		retval = sctp_setsockopt_default_send_param(sk, optval,
4003 							    optlen);
4004 		break;
4005 	case SCTP_DEFAULT_SNDINFO:
4006 		retval = sctp_setsockopt_default_sndinfo(sk, optval, optlen);
4007 		break;
4008 	case SCTP_PRIMARY_ADDR:
4009 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
4010 		break;
4011 	case SCTP_SET_PEER_PRIMARY_ADDR:
4012 		retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
4013 		break;
4014 	case SCTP_NODELAY:
4015 		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
4016 		break;
4017 	case SCTP_RTOINFO:
4018 		retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
4019 		break;
4020 	case SCTP_ASSOCINFO:
4021 		retval = sctp_setsockopt_associnfo(sk, optval, optlen);
4022 		break;
4023 	case SCTP_I_WANT_MAPPED_V4_ADDR:
4024 		retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
4025 		break;
4026 	case SCTP_MAXSEG:
4027 		retval = sctp_setsockopt_maxseg(sk, optval, optlen);
4028 		break;
4029 	case SCTP_ADAPTATION_LAYER:
4030 		retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
4031 		break;
4032 	case SCTP_CONTEXT:
4033 		retval = sctp_setsockopt_context(sk, optval, optlen);
4034 		break;
4035 	case SCTP_FRAGMENT_INTERLEAVE:
4036 		retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
4037 		break;
4038 	case SCTP_MAX_BURST:
4039 		retval = sctp_setsockopt_maxburst(sk, optval, optlen);
4040 		break;
4041 	case SCTP_AUTH_CHUNK:
4042 		retval = sctp_setsockopt_auth_chunk(sk, optval, optlen);
4043 		break;
4044 	case SCTP_HMAC_IDENT:
4045 		retval = sctp_setsockopt_hmac_ident(sk, optval, optlen);
4046 		break;
4047 	case SCTP_AUTH_KEY:
4048 		retval = sctp_setsockopt_auth_key(sk, optval, optlen);
4049 		break;
4050 	case SCTP_AUTH_ACTIVE_KEY:
4051 		retval = sctp_setsockopt_active_key(sk, optval, optlen);
4052 		break;
4053 	case SCTP_AUTH_DELETE_KEY:
4054 		retval = sctp_setsockopt_del_key(sk, optval, optlen);
4055 		break;
4056 	case SCTP_AUTO_ASCONF:
4057 		retval = sctp_setsockopt_auto_asconf(sk, optval, optlen);
4058 		break;
4059 	case SCTP_PEER_ADDR_THLDS:
4060 		retval = sctp_setsockopt_paddr_thresholds(sk, optval, optlen);
4061 		break;
4062 	case SCTP_RECVRCVINFO:
4063 		retval = sctp_setsockopt_recvrcvinfo(sk, optval, optlen);
4064 		break;
4065 	case SCTP_RECVNXTINFO:
4066 		retval = sctp_setsockopt_recvnxtinfo(sk, optval, optlen);
4067 		break;
4068 	case SCTP_PR_SUPPORTED:
4069 		retval = sctp_setsockopt_pr_supported(sk, optval, optlen);
4070 		break;
4071 	case SCTP_DEFAULT_PRINFO:
4072 		retval = sctp_setsockopt_default_prinfo(sk, optval, optlen);
4073 		break;
4074 	case SCTP_RECONFIG_SUPPORTED:
4075 		retval = sctp_setsockopt_reconfig_supported(sk, optval, optlen);
4076 		break;
4077 	case SCTP_ENABLE_STREAM_RESET:
4078 		retval = sctp_setsockopt_enable_strreset(sk, optval, optlen);
4079 		break;
4080 	case SCTP_RESET_STREAMS:
4081 		retval = sctp_setsockopt_reset_streams(sk, optval, optlen);
4082 		break;
4083 	case SCTP_RESET_ASSOC:
4084 		retval = sctp_setsockopt_reset_assoc(sk, optval, optlen);
4085 		break;
4086 	case SCTP_ADD_STREAMS:
4087 		retval = sctp_setsockopt_add_streams(sk, optval, optlen);
4088 		break;
4089 	default:
4090 		retval = -ENOPROTOOPT;
4091 		break;
4092 	}
4093 
4094 	release_sock(sk);
4095 
4096 out_nounlock:
4097 	return retval;
4098 }
4099 
4100 /* API 3.1.6 connect() - UDP Style Syntax
4101  *
4102  * An application may use the connect() call in the UDP model to initiate an
4103  * association without sending data.
4104  *
4105  * The syntax is:
4106  *
4107  * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
4108  *
4109  * sd: the socket descriptor to have a new association added to.
4110  *
4111  * nam: the address structure (either struct sockaddr_in or struct
4112  *    sockaddr_in6 defined in RFC2553 [7]).
4113  *
4114  * len: the size of the address.
4115  */
4116 static int sctp_connect(struct sock *sk, struct sockaddr *addr,
4117 			int addr_len)
4118 {
4119 	int err = 0;
4120 	struct sctp_af *af;
4121 
4122 	lock_sock(sk);
4123 
4124 	pr_debug("%s: sk:%p, sockaddr:%p, addr_len:%d\n", __func__, sk,
4125 		 addr, addr_len);
4126 
4127 	/* Validate addr_len before calling common connect/connectx routine. */
4128 	af = sctp_get_af_specific(addr->sa_family);
4129 	if (!af || addr_len < af->sockaddr_len) {
4130 		err = -EINVAL;
4131 	} else {
4132 		/* Pass correct addr len to common routine (so it knows there
4133 		 * is only one address being passed.
4134 		 */
4135 		err = __sctp_connect(sk, addr, af->sockaddr_len, NULL);
4136 	}
4137 
4138 	release_sock(sk);
4139 	return err;
4140 }
4141 
4142 /* FIXME: Write comments. */
4143 static int sctp_disconnect(struct sock *sk, int flags)
4144 {
4145 	return -EOPNOTSUPP; /* STUB */
4146 }
4147 
4148 /* 4.1.4 accept() - TCP Style Syntax
4149  *
4150  * Applications use accept() call to remove an established SCTP
4151  * association from the accept queue of the endpoint.  A new socket
4152  * descriptor will be returned from accept() to represent the newly
4153  * formed association.
4154  */
4155 static struct sock *sctp_accept(struct sock *sk, int flags, int *err, bool kern)
4156 {
4157 	struct sctp_sock *sp;
4158 	struct sctp_endpoint *ep;
4159 	struct sock *newsk = NULL;
4160 	struct sctp_association *asoc;
4161 	long timeo;
4162 	int error = 0;
4163 
4164 	lock_sock(sk);
4165 
4166 	sp = sctp_sk(sk);
4167 	ep = sp->ep;
4168 
4169 	if (!sctp_style(sk, TCP)) {
4170 		error = -EOPNOTSUPP;
4171 		goto out;
4172 	}
4173 
4174 	if (!sctp_sstate(sk, LISTENING)) {
4175 		error = -EINVAL;
4176 		goto out;
4177 	}
4178 
4179 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
4180 
4181 	error = sctp_wait_for_accept(sk, timeo);
4182 	if (error)
4183 		goto out;
4184 
4185 	/* We treat the list of associations on the endpoint as the accept
4186 	 * queue and pick the first association on the list.
4187 	 */
4188 	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
4189 
4190 	newsk = sp->pf->create_accept_sk(sk, asoc, kern);
4191 	if (!newsk) {
4192 		error = -ENOMEM;
4193 		goto out;
4194 	}
4195 
4196 	/* Populate the fields of the newsk from the oldsk and migrate the
4197 	 * asoc to the newsk.
4198 	 */
4199 	sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
4200 
4201 out:
4202 	release_sock(sk);
4203 	*err = error;
4204 	return newsk;
4205 }
4206 
4207 /* The SCTP ioctl handler. */
4208 static int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
4209 {
4210 	int rc = -ENOTCONN;
4211 
4212 	lock_sock(sk);
4213 
4214 	/*
4215 	 * SEQPACKET-style sockets in LISTENING state are valid, for
4216 	 * SCTP, so only discard TCP-style sockets in LISTENING state.
4217 	 */
4218 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
4219 		goto out;
4220 
4221 	switch (cmd) {
4222 	case SIOCINQ: {
4223 		struct sk_buff *skb;
4224 		unsigned int amount = 0;
4225 
4226 		skb = skb_peek(&sk->sk_receive_queue);
4227 		if (skb != NULL) {
4228 			/*
4229 			 * We will only return the amount of this packet since
4230 			 * that is all that will be read.
4231 			 */
4232 			amount = skb->len;
4233 		}
4234 		rc = put_user(amount, (int __user *)arg);
4235 		break;
4236 	}
4237 	default:
4238 		rc = -ENOIOCTLCMD;
4239 		break;
4240 	}
4241 out:
4242 	release_sock(sk);
4243 	return rc;
4244 }
4245 
4246 /* This is the function which gets called during socket creation to
4247  * initialized the SCTP-specific portion of the sock.
4248  * The sock structure should already be zero-filled memory.
4249  */
4250 static int sctp_init_sock(struct sock *sk)
4251 {
4252 	struct net *net = sock_net(sk);
4253 	struct sctp_sock *sp;
4254 
4255 	pr_debug("%s: sk:%p\n", __func__, sk);
4256 
4257 	sp = sctp_sk(sk);
4258 
4259 	/* Initialize the SCTP per socket area.  */
4260 	switch (sk->sk_type) {
4261 	case SOCK_SEQPACKET:
4262 		sp->type = SCTP_SOCKET_UDP;
4263 		break;
4264 	case SOCK_STREAM:
4265 		sp->type = SCTP_SOCKET_TCP;
4266 		break;
4267 	default:
4268 		return -ESOCKTNOSUPPORT;
4269 	}
4270 
4271 	sk->sk_gso_type = SKB_GSO_SCTP;
4272 
4273 	/* Initialize default send parameters. These parameters can be
4274 	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
4275 	 */
4276 	sp->default_stream = 0;
4277 	sp->default_ppid = 0;
4278 	sp->default_flags = 0;
4279 	sp->default_context = 0;
4280 	sp->default_timetolive = 0;
4281 
4282 	sp->default_rcv_context = 0;
4283 	sp->max_burst = net->sctp.max_burst;
4284 
4285 	sp->sctp_hmac_alg = net->sctp.sctp_hmac_alg;
4286 
4287 	/* Initialize default setup parameters. These parameters
4288 	 * can be modified with the SCTP_INITMSG socket option or
4289 	 * overridden by the SCTP_INIT CMSG.
4290 	 */
4291 	sp->initmsg.sinit_num_ostreams   = sctp_max_outstreams;
4292 	sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
4293 	sp->initmsg.sinit_max_attempts   = net->sctp.max_retrans_init;
4294 	sp->initmsg.sinit_max_init_timeo = net->sctp.rto_max;
4295 
4296 	/* Initialize default RTO related parameters.  These parameters can
4297 	 * be modified for with the SCTP_RTOINFO socket option.
4298 	 */
4299 	sp->rtoinfo.srto_initial = net->sctp.rto_initial;
4300 	sp->rtoinfo.srto_max     = net->sctp.rto_max;
4301 	sp->rtoinfo.srto_min     = net->sctp.rto_min;
4302 
4303 	/* Initialize default association related parameters. These parameters
4304 	 * can be modified with the SCTP_ASSOCINFO socket option.
4305 	 */
4306 	sp->assocparams.sasoc_asocmaxrxt = net->sctp.max_retrans_association;
4307 	sp->assocparams.sasoc_number_peer_destinations = 0;
4308 	sp->assocparams.sasoc_peer_rwnd = 0;
4309 	sp->assocparams.sasoc_local_rwnd = 0;
4310 	sp->assocparams.sasoc_cookie_life = net->sctp.valid_cookie_life;
4311 
4312 	/* Initialize default event subscriptions. By default, all the
4313 	 * options are off.
4314 	 */
4315 	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
4316 
4317 	/* Default Peer Address Parameters.  These defaults can
4318 	 * be modified via SCTP_PEER_ADDR_PARAMS
4319 	 */
4320 	sp->hbinterval  = net->sctp.hb_interval;
4321 	sp->pathmaxrxt  = net->sctp.max_retrans_path;
4322 	sp->pathmtu     = 0; /* allow default discovery */
4323 	sp->sackdelay   = net->sctp.sack_timeout;
4324 	sp->sackfreq	= 2;
4325 	sp->param_flags = SPP_HB_ENABLE |
4326 			  SPP_PMTUD_ENABLE |
4327 			  SPP_SACKDELAY_ENABLE;
4328 
4329 	/* If enabled no SCTP message fragmentation will be performed.
4330 	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
4331 	 */
4332 	sp->disable_fragments = 0;
4333 
4334 	/* Enable Nagle algorithm by default.  */
4335 	sp->nodelay           = 0;
4336 
4337 	sp->recvrcvinfo = 0;
4338 	sp->recvnxtinfo = 0;
4339 
4340 	/* Enable by default. */
4341 	sp->v4mapped          = 1;
4342 
4343 	/* Auto-close idle associations after the configured
4344 	 * number of seconds.  A value of 0 disables this
4345 	 * feature.  Configure through the SCTP_AUTOCLOSE socket option,
4346 	 * for UDP-style sockets only.
4347 	 */
4348 	sp->autoclose         = 0;
4349 
4350 	/* User specified fragmentation limit. */
4351 	sp->user_frag         = 0;
4352 
4353 	sp->adaptation_ind = 0;
4354 
4355 	sp->pf = sctp_get_pf_specific(sk->sk_family);
4356 
4357 	/* Control variables for partial data delivery. */
4358 	atomic_set(&sp->pd_mode, 0);
4359 	skb_queue_head_init(&sp->pd_lobby);
4360 	sp->frag_interleave = 0;
4361 
4362 	/* Create a per socket endpoint structure.  Even if we
4363 	 * change the data structure relationships, this may still
4364 	 * be useful for storing pre-connect address information.
4365 	 */
4366 	sp->ep = sctp_endpoint_new(sk, GFP_KERNEL);
4367 	if (!sp->ep)
4368 		return -ENOMEM;
4369 
4370 	sp->hmac = NULL;
4371 
4372 	sk->sk_destruct = sctp_destruct_sock;
4373 
4374 	SCTP_DBG_OBJCNT_INC(sock);
4375 
4376 	local_bh_disable();
4377 	percpu_counter_inc(&sctp_sockets_allocated);
4378 	sock_prot_inuse_add(net, sk->sk_prot, 1);
4379 
4380 	/* Nothing can fail after this block, otherwise
4381 	 * sctp_destroy_sock() will be called without addr_wq_lock held
4382 	 */
4383 	if (net->sctp.default_auto_asconf) {
4384 		spin_lock(&sock_net(sk)->sctp.addr_wq_lock);
4385 		list_add_tail(&sp->auto_asconf_list,
4386 		    &net->sctp.auto_asconf_splist);
4387 		sp->do_auto_asconf = 1;
4388 		spin_unlock(&sock_net(sk)->sctp.addr_wq_lock);
4389 	} else {
4390 		sp->do_auto_asconf = 0;
4391 	}
4392 
4393 	local_bh_enable();
4394 
4395 	return 0;
4396 }
4397 
4398 /* Cleanup any SCTP per socket resources. Must be called with
4399  * sock_net(sk)->sctp.addr_wq_lock held if sp->do_auto_asconf is true
4400  */
4401 static void sctp_destroy_sock(struct sock *sk)
4402 {
4403 	struct sctp_sock *sp;
4404 
4405 	pr_debug("%s: sk:%p\n", __func__, sk);
4406 
4407 	/* Release our hold on the endpoint. */
4408 	sp = sctp_sk(sk);
4409 	/* This could happen during socket init, thus we bail out
4410 	 * early, since the rest of the below is not setup either.
4411 	 */
4412 	if (sp->ep == NULL)
4413 		return;
4414 
4415 	if (sp->do_auto_asconf) {
4416 		sp->do_auto_asconf = 0;
4417 		list_del(&sp->auto_asconf_list);
4418 	}
4419 	sctp_endpoint_free(sp->ep);
4420 	local_bh_disable();
4421 	percpu_counter_dec(&sctp_sockets_allocated);
4422 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
4423 	local_bh_enable();
4424 }
4425 
4426 /* Triggered when there are no references on the socket anymore */
4427 static void sctp_destruct_sock(struct sock *sk)
4428 {
4429 	struct sctp_sock *sp = sctp_sk(sk);
4430 
4431 	/* Free up the HMAC transform. */
4432 	crypto_free_shash(sp->hmac);
4433 
4434 	inet_sock_destruct(sk);
4435 }
4436 
4437 /* API 4.1.7 shutdown() - TCP Style Syntax
4438  *     int shutdown(int socket, int how);
4439  *
4440  *     sd      - the socket descriptor of the association to be closed.
4441  *     how     - Specifies the type of shutdown.  The  values  are
4442  *               as follows:
4443  *               SHUT_RD
4444  *                     Disables further receive operations. No SCTP
4445  *                     protocol action is taken.
4446  *               SHUT_WR
4447  *                     Disables further send operations, and initiates
4448  *                     the SCTP shutdown sequence.
4449  *               SHUT_RDWR
4450  *                     Disables further send  and  receive  operations
4451  *                     and initiates the SCTP shutdown sequence.
4452  */
4453 static void sctp_shutdown(struct sock *sk, int how)
4454 {
4455 	struct net *net = sock_net(sk);
4456 	struct sctp_endpoint *ep;
4457 
4458 	if (!sctp_style(sk, TCP))
4459 		return;
4460 
4461 	ep = sctp_sk(sk)->ep;
4462 	if (how & SEND_SHUTDOWN && !list_empty(&ep->asocs)) {
4463 		struct sctp_association *asoc;
4464 
4465 		sk->sk_state = SCTP_SS_CLOSING;
4466 		asoc = list_entry(ep->asocs.next,
4467 				  struct sctp_association, asocs);
4468 		sctp_primitive_SHUTDOWN(net, asoc, NULL);
4469 	}
4470 }
4471 
4472 int sctp_get_sctp_info(struct sock *sk, struct sctp_association *asoc,
4473 		       struct sctp_info *info)
4474 {
4475 	struct sctp_transport *prim;
4476 	struct list_head *pos;
4477 	int mask;
4478 
4479 	memset(info, 0, sizeof(*info));
4480 	if (!asoc) {
4481 		struct sctp_sock *sp = sctp_sk(sk);
4482 
4483 		info->sctpi_s_autoclose = sp->autoclose;
4484 		info->sctpi_s_adaptation_ind = sp->adaptation_ind;
4485 		info->sctpi_s_pd_point = sp->pd_point;
4486 		info->sctpi_s_nodelay = sp->nodelay;
4487 		info->sctpi_s_disable_fragments = sp->disable_fragments;
4488 		info->sctpi_s_v4mapped = sp->v4mapped;
4489 		info->sctpi_s_frag_interleave = sp->frag_interleave;
4490 		info->sctpi_s_type = sp->type;
4491 
4492 		return 0;
4493 	}
4494 
4495 	info->sctpi_tag = asoc->c.my_vtag;
4496 	info->sctpi_state = asoc->state;
4497 	info->sctpi_rwnd = asoc->a_rwnd;
4498 	info->sctpi_unackdata = asoc->unack_data;
4499 	info->sctpi_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
4500 	info->sctpi_instrms = asoc->stream.incnt;
4501 	info->sctpi_outstrms = asoc->stream.outcnt;
4502 	list_for_each(pos, &asoc->base.inqueue.in_chunk_list)
4503 		info->sctpi_inqueue++;
4504 	list_for_each(pos, &asoc->outqueue.out_chunk_list)
4505 		info->sctpi_outqueue++;
4506 	info->sctpi_overall_error = asoc->overall_error_count;
4507 	info->sctpi_max_burst = asoc->max_burst;
4508 	info->sctpi_maxseg = asoc->frag_point;
4509 	info->sctpi_peer_rwnd = asoc->peer.rwnd;
4510 	info->sctpi_peer_tag = asoc->c.peer_vtag;
4511 
4512 	mask = asoc->peer.ecn_capable << 1;
4513 	mask = (mask | asoc->peer.ipv4_address) << 1;
4514 	mask = (mask | asoc->peer.ipv6_address) << 1;
4515 	mask = (mask | asoc->peer.hostname_address) << 1;
4516 	mask = (mask | asoc->peer.asconf_capable) << 1;
4517 	mask = (mask | asoc->peer.prsctp_capable) << 1;
4518 	mask = (mask | asoc->peer.auth_capable);
4519 	info->sctpi_peer_capable = mask;
4520 	mask = asoc->peer.sack_needed << 1;
4521 	mask = (mask | asoc->peer.sack_generation) << 1;
4522 	mask = (mask | asoc->peer.zero_window_announced);
4523 	info->sctpi_peer_sack = mask;
4524 
4525 	info->sctpi_isacks = asoc->stats.isacks;
4526 	info->sctpi_osacks = asoc->stats.osacks;
4527 	info->sctpi_opackets = asoc->stats.opackets;
4528 	info->sctpi_ipackets = asoc->stats.ipackets;
4529 	info->sctpi_rtxchunks = asoc->stats.rtxchunks;
4530 	info->sctpi_outofseqtsns = asoc->stats.outofseqtsns;
4531 	info->sctpi_idupchunks = asoc->stats.idupchunks;
4532 	info->sctpi_gapcnt = asoc->stats.gapcnt;
4533 	info->sctpi_ouodchunks = asoc->stats.ouodchunks;
4534 	info->sctpi_iuodchunks = asoc->stats.iuodchunks;
4535 	info->sctpi_oodchunks = asoc->stats.oodchunks;
4536 	info->sctpi_iodchunks = asoc->stats.iodchunks;
4537 	info->sctpi_octrlchunks = asoc->stats.octrlchunks;
4538 	info->sctpi_ictrlchunks = asoc->stats.ictrlchunks;
4539 
4540 	prim = asoc->peer.primary_path;
4541 	memcpy(&info->sctpi_p_address, &prim->ipaddr,
4542 	       sizeof(struct sockaddr_storage));
4543 	info->sctpi_p_state = prim->state;
4544 	info->sctpi_p_cwnd = prim->cwnd;
4545 	info->sctpi_p_srtt = prim->srtt;
4546 	info->sctpi_p_rto = jiffies_to_msecs(prim->rto);
4547 	info->sctpi_p_hbinterval = prim->hbinterval;
4548 	info->sctpi_p_pathmaxrxt = prim->pathmaxrxt;
4549 	info->sctpi_p_sackdelay = jiffies_to_msecs(prim->sackdelay);
4550 	info->sctpi_p_ssthresh = prim->ssthresh;
4551 	info->sctpi_p_partial_bytes_acked = prim->partial_bytes_acked;
4552 	info->sctpi_p_flight_size = prim->flight_size;
4553 	info->sctpi_p_error = prim->error_count;
4554 
4555 	return 0;
4556 }
4557 EXPORT_SYMBOL_GPL(sctp_get_sctp_info);
4558 
4559 /* use callback to avoid exporting the core structure */
4560 int sctp_transport_walk_start(struct rhashtable_iter *iter)
4561 {
4562 	int err;
4563 
4564 	rhltable_walk_enter(&sctp_transport_hashtable, iter);
4565 
4566 	err = rhashtable_walk_start(iter);
4567 	if (err && err != -EAGAIN) {
4568 		rhashtable_walk_stop(iter);
4569 		rhashtable_walk_exit(iter);
4570 		return err;
4571 	}
4572 
4573 	return 0;
4574 }
4575 
4576 void sctp_transport_walk_stop(struct rhashtable_iter *iter)
4577 {
4578 	rhashtable_walk_stop(iter);
4579 	rhashtable_walk_exit(iter);
4580 }
4581 
4582 struct sctp_transport *sctp_transport_get_next(struct net *net,
4583 					       struct rhashtable_iter *iter)
4584 {
4585 	struct sctp_transport *t;
4586 
4587 	t = rhashtable_walk_next(iter);
4588 	for (; t; t = rhashtable_walk_next(iter)) {
4589 		if (IS_ERR(t)) {
4590 			if (PTR_ERR(t) == -EAGAIN)
4591 				continue;
4592 			break;
4593 		}
4594 
4595 		if (net_eq(sock_net(t->asoc->base.sk), net) &&
4596 		    t->asoc->peer.primary_path == t)
4597 			break;
4598 	}
4599 
4600 	return t;
4601 }
4602 
4603 struct sctp_transport *sctp_transport_get_idx(struct net *net,
4604 					      struct rhashtable_iter *iter,
4605 					      int pos)
4606 {
4607 	void *obj = SEQ_START_TOKEN;
4608 
4609 	while (pos && (obj = sctp_transport_get_next(net, iter)) &&
4610 	       !IS_ERR(obj))
4611 		pos--;
4612 
4613 	return obj;
4614 }
4615 
4616 int sctp_for_each_endpoint(int (*cb)(struct sctp_endpoint *, void *),
4617 			   void *p) {
4618 	int err = 0;
4619 	int hash = 0;
4620 	struct sctp_ep_common *epb;
4621 	struct sctp_hashbucket *head;
4622 
4623 	for (head = sctp_ep_hashtable; hash < sctp_ep_hashsize;
4624 	     hash++, head++) {
4625 		read_lock_bh(&head->lock);
4626 		sctp_for_each_hentry(epb, &head->chain) {
4627 			err = cb(sctp_ep(epb), p);
4628 			if (err)
4629 				break;
4630 		}
4631 		read_unlock_bh(&head->lock);
4632 	}
4633 
4634 	return err;
4635 }
4636 EXPORT_SYMBOL_GPL(sctp_for_each_endpoint);
4637 
4638 int sctp_transport_lookup_process(int (*cb)(struct sctp_transport *, void *),
4639 				  struct net *net,
4640 				  const union sctp_addr *laddr,
4641 				  const union sctp_addr *paddr, void *p)
4642 {
4643 	struct sctp_transport *transport;
4644 	int err;
4645 
4646 	rcu_read_lock();
4647 	transport = sctp_addrs_lookup_transport(net, laddr, paddr);
4648 	rcu_read_unlock();
4649 	if (!transport)
4650 		return -ENOENT;
4651 
4652 	err = cb(transport, p);
4653 	sctp_transport_put(transport);
4654 
4655 	return err;
4656 }
4657 EXPORT_SYMBOL_GPL(sctp_transport_lookup_process);
4658 
4659 int sctp_for_each_transport(int (*cb)(struct sctp_transport *, void *),
4660 			    struct net *net, int pos, void *p) {
4661 	struct rhashtable_iter hti;
4662 	void *obj;
4663 	int err;
4664 
4665 	err = sctp_transport_walk_start(&hti);
4666 	if (err)
4667 		return err;
4668 
4669 	obj = sctp_transport_get_idx(net, &hti, pos + 1);
4670 	for (; !IS_ERR_OR_NULL(obj); obj = sctp_transport_get_next(net, &hti)) {
4671 		struct sctp_transport *transport = obj;
4672 
4673 		if (!sctp_transport_hold(transport))
4674 			continue;
4675 		err = cb(transport, p);
4676 		sctp_transport_put(transport);
4677 		if (err)
4678 			break;
4679 	}
4680 	sctp_transport_walk_stop(&hti);
4681 
4682 	return err;
4683 }
4684 EXPORT_SYMBOL_GPL(sctp_for_each_transport);
4685 
4686 /* 7.2.1 Association Status (SCTP_STATUS)
4687 
4688  * Applications can retrieve current status information about an
4689  * association, including association state, peer receiver window size,
4690  * number of unacked data chunks, and number of data chunks pending
4691  * receipt.  This information is read-only.
4692  */
4693 static int sctp_getsockopt_sctp_status(struct sock *sk, int len,
4694 				       char __user *optval,
4695 				       int __user *optlen)
4696 {
4697 	struct sctp_status status;
4698 	struct sctp_association *asoc = NULL;
4699 	struct sctp_transport *transport;
4700 	sctp_assoc_t associd;
4701 	int retval = 0;
4702 
4703 	if (len < sizeof(status)) {
4704 		retval = -EINVAL;
4705 		goto out;
4706 	}
4707 
4708 	len = sizeof(status);
4709 	if (copy_from_user(&status, optval, len)) {
4710 		retval = -EFAULT;
4711 		goto out;
4712 	}
4713 
4714 	associd = status.sstat_assoc_id;
4715 	asoc = sctp_id2assoc(sk, associd);
4716 	if (!asoc) {
4717 		retval = -EINVAL;
4718 		goto out;
4719 	}
4720 
4721 	transport = asoc->peer.primary_path;
4722 
4723 	status.sstat_assoc_id = sctp_assoc2id(asoc);
4724 	status.sstat_state = sctp_assoc_to_state(asoc);
4725 	status.sstat_rwnd =  asoc->peer.rwnd;
4726 	status.sstat_unackdata = asoc->unack_data;
4727 
4728 	status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
4729 	status.sstat_instrms = asoc->stream.incnt;
4730 	status.sstat_outstrms = asoc->stream.outcnt;
4731 	status.sstat_fragmentation_point = asoc->frag_point;
4732 	status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
4733 	memcpy(&status.sstat_primary.spinfo_address, &transport->ipaddr,
4734 			transport->af_specific->sockaddr_len);
4735 	/* Map ipv4 address into v4-mapped-on-v6 address.  */
4736 	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sctp_sk(sk),
4737 		(union sctp_addr *)&status.sstat_primary.spinfo_address);
4738 	status.sstat_primary.spinfo_state = transport->state;
4739 	status.sstat_primary.spinfo_cwnd = transport->cwnd;
4740 	status.sstat_primary.spinfo_srtt = transport->srtt;
4741 	status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
4742 	status.sstat_primary.spinfo_mtu = transport->pathmtu;
4743 
4744 	if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
4745 		status.sstat_primary.spinfo_state = SCTP_ACTIVE;
4746 
4747 	if (put_user(len, optlen)) {
4748 		retval = -EFAULT;
4749 		goto out;
4750 	}
4751 
4752 	pr_debug("%s: len:%d, state:%d, rwnd:%d, assoc_id:%d\n",
4753 		 __func__, len, status.sstat_state, status.sstat_rwnd,
4754 		 status.sstat_assoc_id);
4755 
4756 	if (copy_to_user(optval, &status, len)) {
4757 		retval = -EFAULT;
4758 		goto out;
4759 	}
4760 
4761 out:
4762 	return retval;
4763 }
4764 
4765 
4766 /* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
4767  *
4768  * Applications can retrieve information about a specific peer address
4769  * of an association, including its reachability state, congestion
4770  * window, and retransmission timer values.  This information is
4771  * read-only.
4772  */
4773 static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
4774 					  char __user *optval,
4775 					  int __user *optlen)
4776 {
4777 	struct sctp_paddrinfo pinfo;
4778 	struct sctp_transport *transport;
4779 	int retval = 0;
4780 
4781 	if (len < sizeof(pinfo)) {
4782 		retval = -EINVAL;
4783 		goto out;
4784 	}
4785 
4786 	len = sizeof(pinfo);
4787 	if (copy_from_user(&pinfo, optval, len)) {
4788 		retval = -EFAULT;
4789 		goto out;
4790 	}
4791 
4792 	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
4793 					   pinfo.spinfo_assoc_id);
4794 	if (!transport)
4795 		return -EINVAL;
4796 
4797 	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
4798 	pinfo.spinfo_state = transport->state;
4799 	pinfo.spinfo_cwnd = transport->cwnd;
4800 	pinfo.spinfo_srtt = transport->srtt;
4801 	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
4802 	pinfo.spinfo_mtu = transport->pathmtu;
4803 
4804 	if (pinfo.spinfo_state == SCTP_UNKNOWN)
4805 		pinfo.spinfo_state = SCTP_ACTIVE;
4806 
4807 	if (put_user(len, optlen)) {
4808 		retval = -EFAULT;
4809 		goto out;
4810 	}
4811 
4812 	if (copy_to_user(optval, &pinfo, len)) {
4813 		retval = -EFAULT;
4814 		goto out;
4815 	}
4816 
4817 out:
4818 	return retval;
4819 }
4820 
4821 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
4822  *
4823  * This option is a on/off flag.  If enabled no SCTP message
4824  * fragmentation will be performed.  Instead if a message being sent
4825  * exceeds the current PMTU size, the message will NOT be sent and
4826  * instead a error will be indicated to the user.
4827  */
4828 static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
4829 					char __user *optval, int __user *optlen)
4830 {
4831 	int val;
4832 
4833 	if (len < sizeof(int))
4834 		return -EINVAL;
4835 
4836 	len = sizeof(int);
4837 	val = (sctp_sk(sk)->disable_fragments == 1);
4838 	if (put_user(len, optlen))
4839 		return -EFAULT;
4840 	if (copy_to_user(optval, &val, len))
4841 		return -EFAULT;
4842 	return 0;
4843 }
4844 
4845 /* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
4846  *
4847  * This socket option is used to specify various notifications and
4848  * ancillary data the user wishes to receive.
4849  */
4850 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
4851 				  int __user *optlen)
4852 {
4853 	if (len == 0)
4854 		return -EINVAL;
4855 	if (len > sizeof(struct sctp_event_subscribe))
4856 		len = sizeof(struct sctp_event_subscribe);
4857 	if (put_user(len, optlen))
4858 		return -EFAULT;
4859 	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
4860 		return -EFAULT;
4861 	return 0;
4862 }
4863 
4864 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
4865  *
4866  * This socket option is applicable to the UDP-style socket only.  When
4867  * set it will cause associations that are idle for more than the
4868  * specified number of seconds to automatically close.  An association
4869  * being idle is defined an association that has NOT sent or received
4870  * user data.  The special value of '0' indicates that no automatic
4871  * close of any associations should be performed.  The option expects an
4872  * integer defining the number of seconds of idle time before an
4873  * association is closed.
4874  */
4875 static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
4876 {
4877 	/* Applicable to UDP-style socket only */
4878 	if (sctp_style(sk, TCP))
4879 		return -EOPNOTSUPP;
4880 	if (len < sizeof(int))
4881 		return -EINVAL;
4882 	len = sizeof(int);
4883 	if (put_user(len, optlen))
4884 		return -EFAULT;
4885 	if (copy_to_user(optval, &sctp_sk(sk)->autoclose, sizeof(int)))
4886 		return -EFAULT;
4887 	return 0;
4888 }
4889 
4890 /* Helper routine to branch off an association to a new socket.  */
4891 int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp)
4892 {
4893 	struct sctp_association *asoc = sctp_id2assoc(sk, id);
4894 	struct sctp_sock *sp = sctp_sk(sk);
4895 	struct socket *sock;
4896 	int err = 0;
4897 
4898 	if (!asoc)
4899 		return -EINVAL;
4900 
4901 	/* If there is a thread waiting on more sndbuf space for
4902 	 * sending on this asoc, it cannot be peeled.
4903 	 */
4904 	if (waitqueue_active(&asoc->wait))
4905 		return -EBUSY;
4906 
4907 	/* An association cannot be branched off from an already peeled-off
4908 	 * socket, nor is this supported for tcp style sockets.
4909 	 */
4910 	if (!sctp_style(sk, UDP))
4911 		return -EINVAL;
4912 
4913 	/* Create a new socket.  */
4914 	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
4915 	if (err < 0)
4916 		return err;
4917 
4918 	sctp_copy_sock(sock->sk, sk, asoc);
4919 
4920 	/* Make peeled-off sockets more like 1-1 accepted sockets.
4921 	 * Set the daddr and initialize id to something more random
4922 	 */
4923 	sp->pf->to_sk_daddr(&asoc->peer.primary_addr, sk);
4924 
4925 	/* Populate the fields of the newsk from the oldsk and migrate the
4926 	 * asoc to the newsk.
4927 	 */
4928 	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
4929 
4930 	*sockp = sock;
4931 
4932 	return err;
4933 }
4934 EXPORT_SYMBOL(sctp_do_peeloff);
4935 
4936 static int sctp_getsockopt_peeloff_common(struct sock *sk, sctp_peeloff_arg_t *peeloff,
4937 					  struct file **newfile, unsigned flags)
4938 {
4939 	struct socket *newsock;
4940 	int retval;
4941 
4942 	retval = sctp_do_peeloff(sk, peeloff->associd, &newsock);
4943 	if (retval < 0)
4944 		goto out;
4945 
4946 	/* Map the socket to an unused fd that can be returned to the user.  */
4947 	retval = get_unused_fd_flags(flags & SOCK_CLOEXEC);
4948 	if (retval < 0) {
4949 		sock_release(newsock);
4950 		goto out;
4951 	}
4952 
4953 	*newfile = sock_alloc_file(newsock, 0, NULL);
4954 	if (IS_ERR(*newfile)) {
4955 		put_unused_fd(retval);
4956 		sock_release(newsock);
4957 		retval = PTR_ERR(*newfile);
4958 		*newfile = NULL;
4959 		return retval;
4960 	}
4961 
4962 	pr_debug("%s: sk:%p, newsk:%p, sd:%d\n", __func__, sk, newsock->sk,
4963 		 retval);
4964 
4965 	peeloff->sd = retval;
4966 
4967 	if (flags & SOCK_NONBLOCK)
4968 		(*newfile)->f_flags |= O_NONBLOCK;
4969 out:
4970 	return retval;
4971 }
4972 
4973 static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
4974 {
4975 	sctp_peeloff_arg_t peeloff;
4976 	struct file *newfile = NULL;
4977 	int retval = 0;
4978 
4979 	if (len < sizeof(sctp_peeloff_arg_t))
4980 		return -EINVAL;
4981 	len = sizeof(sctp_peeloff_arg_t);
4982 	if (copy_from_user(&peeloff, optval, len))
4983 		return -EFAULT;
4984 
4985 	retval = sctp_getsockopt_peeloff_common(sk, &peeloff, &newfile, 0);
4986 	if (retval < 0)
4987 		goto out;
4988 
4989 	/* Return the fd mapped to the new socket.  */
4990 	if (put_user(len, optlen)) {
4991 		fput(newfile);
4992 		put_unused_fd(retval);
4993 		return -EFAULT;
4994 	}
4995 
4996 	if (copy_to_user(optval, &peeloff, len)) {
4997 		fput(newfile);
4998 		put_unused_fd(retval);
4999 		return -EFAULT;
5000 	}
5001 	fd_install(retval, newfile);
5002 out:
5003 	return retval;
5004 }
5005 
5006 static int sctp_getsockopt_peeloff_flags(struct sock *sk, int len,
5007 					 char __user *optval, int __user *optlen)
5008 {
5009 	sctp_peeloff_flags_arg_t peeloff;
5010 	struct file *newfile = NULL;
5011 	int retval = 0;
5012 
5013 	if (len < sizeof(sctp_peeloff_flags_arg_t))
5014 		return -EINVAL;
5015 	len = sizeof(sctp_peeloff_flags_arg_t);
5016 	if (copy_from_user(&peeloff, optval, len))
5017 		return -EFAULT;
5018 
5019 	retval = sctp_getsockopt_peeloff_common(sk, &peeloff.p_arg,
5020 						&newfile, peeloff.flags);
5021 	if (retval < 0)
5022 		goto out;
5023 
5024 	/* Return the fd mapped to the new socket.  */
5025 	if (put_user(len, optlen)) {
5026 		fput(newfile);
5027 		put_unused_fd(retval);
5028 		return -EFAULT;
5029 	}
5030 
5031 	if (copy_to_user(optval, &peeloff, len)) {
5032 		fput(newfile);
5033 		put_unused_fd(retval);
5034 		return -EFAULT;
5035 	}
5036 	fd_install(retval, newfile);
5037 out:
5038 	return retval;
5039 }
5040 
5041 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
5042  *
5043  * Applications can enable or disable heartbeats for any peer address of
5044  * an association, modify an address's heartbeat interval, force a
5045  * heartbeat to be sent immediately, and adjust the address's maximum
5046  * number of retransmissions sent before an address is considered
5047  * unreachable.  The following structure is used to access and modify an
5048  * address's parameters:
5049  *
5050  *  struct sctp_paddrparams {
5051  *     sctp_assoc_t            spp_assoc_id;
5052  *     struct sockaddr_storage spp_address;
5053  *     uint32_t                spp_hbinterval;
5054  *     uint16_t                spp_pathmaxrxt;
5055  *     uint32_t                spp_pathmtu;
5056  *     uint32_t                spp_sackdelay;
5057  *     uint32_t                spp_flags;
5058  * };
5059  *
5060  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
5061  *                     application, and identifies the association for
5062  *                     this query.
5063  *   spp_address     - This specifies which address is of interest.
5064  *   spp_hbinterval  - This contains the value of the heartbeat interval,
5065  *                     in milliseconds.  If a  value of zero
5066  *                     is present in this field then no changes are to
5067  *                     be made to this parameter.
5068  *   spp_pathmaxrxt  - This contains the maximum number of
5069  *                     retransmissions before this address shall be
5070  *                     considered unreachable. If a  value of zero
5071  *                     is present in this field then no changes are to
5072  *                     be made to this parameter.
5073  *   spp_pathmtu     - When Path MTU discovery is disabled the value
5074  *                     specified here will be the "fixed" path mtu.
5075  *                     Note that if the spp_address field is empty
5076  *                     then all associations on this address will
5077  *                     have this fixed path mtu set upon them.
5078  *
5079  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
5080  *                     the number of milliseconds that sacks will be delayed
5081  *                     for. This value will apply to all addresses of an
5082  *                     association if the spp_address field is empty. Note
5083  *                     also, that if delayed sack is enabled and this
5084  *                     value is set to 0, no change is made to the last
5085  *                     recorded delayed sack timer value.
5086  *
5087  *   spp_flags       - These flags are used to control various features
5088  *                     on an association. The flag field may contain
5089  *                     zero or more of the following options.
5090  *
5091  *                     SPP_HB_ENABLE  - Enable heartbeats on the
5092  *                     specified address. Note that if the address
5093  *                     field is empty all addresses for the association
5094  *                     have heartbeats enabled upon them.
5095  *
5096  *                     SPP_HB_DISABLE - Disable heartbeats on the
5097  *                     speicifed address. Note that if the address
5098  *                     field is empty all addresses for the association
5099  *                     will have their heartbeats disabled. Note also
5100  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
5101  *                     mutually exclusive, only one of these two should
5102  *                     be specified. Enabling both fields will have
5103  *                     undetermined results.
5104  *
5105  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
5106  *                     to be made immediately.
5107  *
5108  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
5109  *                     discovery upon the specified address. Note that
5110  *                     if the address feild is empty then all addresses
5111  *                     on the association are effected.
5112  *
5113  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
5114  *                     discovery upon the specified address. Note that
5115  *                     if the address feild is empty then all addresses
5116  *                     on the association are effected. Not also that
5117  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
5118  *                     exclusive. Enabling both will have undetermined
5119  *                     results.
5120  *
5121  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
5122  *                     on delayed sack. The time specified in spp_sackdelay
5123  *                     is used to specify the sack delay for this address. Note
5124  *                     that if spp_address is empty then all addresses will
5125  *                     enable delayed sack and take on the sack delay
5126  *                     value specified in spp_sackdelay.
5127  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
5128  *                     off delayed sack. If the spp_address field is blank then
5129  *                     delayed sack is disabled for the entire association. Note
5130  *                     also that this field is mutually exclusive to
5131  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
5132  *                     results.
5133  */
5134 static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
5135 					    char __user *optval, int __user *optlen)
5136 {
5137 	struct sctp_paddrparams  params;
5138 	struct sctp_transport   *trans = NULL;
5139 	struct sctp_association *asoc = NULL;
5140 	struct sctp_sock        *sp = sctp_sk(sk);
5141 
5142 	if (len < sizeof(struct sctp_paddrparams))
5143 		return -EINVAL;
5144 	len = sizeof(struct sctp_paddrparams);
5145 	if (copy_from_user(&params, optval, len))
5146 		return -EFAULT;
5147 
5148 	/* If an address other than INADDR_ANY is specified, and
5149 	 * no transport is found, then the request is invalid.
5150 	 */
5151 	if (!sctp_is_any(sk, (union sctp_addr *)&params.spp_address)) {
5152 		trans = sctp_addr_id2transport(sk, &params.spp_address,
5153 					       params.spp_assoc_id);
5154 		if (!trans) {
5155 			pr_debug("%s: failed no transport\n", __func__);
5156 			return -EINVAL;
5157 		}
5158 	}
5159 
5160 	/* Get association, if assoc_id != 0 and the socket is a one
5161 	 * to many style socket, and an association was not found, then
5162 	 * the id was invalid.
5163 	 */
5164 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
5165 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
5166 		pr_debug("%s: failed no association\n", __func__);
5167 		return -EINVAL;
5168 	}
5169 
5170 	if (trans) {
5171 		/* Fetch transport values. */
5172 		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
5173 		params.spp_pathmtu    = trans->pathmtu;
5174 		params.spp_pathmaxrxt = trans->pathmaxrxt;
5175 		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
5176 
5177 		/*draft-11 doesn't say what to return in spp_flags*/
5178 		params.spp_flags      = trans->param_flags;
5179 	} else if (asoc) {
5180 		/* Fetch association values. */
5181 		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
5182 		params.spp_pathmtu    = asoc->pathmtu;
5183 		params.spp_pathmaxrxt = asoc->pathmaxrxt;
5184 		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
5185 
5186 		/*draft-11 doesn't say what to return in spp_flags*/
5187 		params.spp_flags      = asoc->param_flags;
5188 	} else {
5189 		/* Fetch socket values. */
5190 		params.spp_hbinterval = sp->hbinterval;
5191 		params.spp_pathmtu    = sp->pathmtu;
5192 		params.spp_sackdelay  = sp->sackdelay;
5193 		params.spp_pathmaxrxt = sp->pathmaxrxt;
5194 
5195 		/*draft-11 doesn't say what to return in spp_flags*/
5196 		params.spp_flags      = sp->param_flags;
5197 	}
5198 
5199 	if (copy_to_user(optval, &params, len))
5200 		return -EFAULT;
5201 
5202 	if (put_user(len, optlen))
5203 		return -EFAULT;
5204 
5205 	return 0;
5206 }
5207 
5208 /*
5209  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
5210  *
5211  * This option will effect the way delayed acks are performed.  This
5212  * option allows you to get or set the delayed ack time, in
5213  * milliseconds.  It also allows changing the delayed ack frequency.
5214  * Changing the frequency to 1 disables the delayed sack algorithm.  If
5215  * the assoc_id is 0, then this sets or gets the endpoints default
5216  * values.  If the assoc_id field is non-zero, then the set or get
5217  * effects the specified association for the one to many model (the
5218  * assoc_id field is ignored by the one to one model).  Note that if
5219  * sack_delay or sack_freq are 0 when setting this option, then the
5220  * current values will remain unchanged.
5221  *
5222  * struct sctp_sack_info {
5223  *     sctp_assoc_t            sack_assoc_id;
5224  *     uint32_t                sack_delay;
5225  *     uint32_t                sack_freq;
5226  * };
5227  *
5228  * sack_assoc_id -  This parameter, indicates which association the user
5229  *    is performing an action upon.  Note that if this field's value is
5230  *    zero then the endpoints default value is changed (effecting future
5231  *    associations only).
5232  *
5233  * sack_delay -  This parameter contains the number of milliseconds that
5234  *    the user is requesting the delayed ACK timer be set to.  Note that
5235  *    this value is defined in the standard to be between 200 and 500
5236  *    milliseconds.
5237  *
5238  * sack_freq -  This parameter contains the number of packets that must
5239  *    be received before a sack is sent without waiting for the delay
5240  *    timer to expire.  The default value for this is 2, setting this
5241  *    value to 1 will disable the delayed sack algorithm.
5242  */
5243 static int sctp_getsockopt_delayed_ack(struct sock *sk, int len,
5244 					    char __user *optval,
5245 					    int __user *optlen)
5246 {
5247 	struct sctp_sack_info    params;
5248 	struct sctp_association *asoc = NULL;
5249 	struct sctp_sock        *sp = sctp_sk(sk);
5250 
5251 	if (len >= sizeof(struct sctp_sack_info)) {
5252 		len = sizeof(struct sctp_sack_info);
5253 
5254 		if (copy_from_user(&params, optval, len))
5255 			return -EFAULT;
5256 	} else if (len == sizeof(struct sctp_assoc_value)) {
5257 		pr_warn_ratelimited(DEPRECATED
5258 				    "%s (pid %d) "
5259 				    "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
5260 				    "Use struct sctp_sack_info instead\n",
5261 				    current->comm, task_pid_nr(current));
5262 		if (copy_from_user(&params, optval, len))
5263 			return -EFAULT;
5264 	} else
5265 		return -EINVAL;
5266 
5267 	/* Get association, if sack_assoc_id != 0 and the socket is a one
5268 	 * to many style socket, and an association was not found, then
5269 	 * the id was invalid.
5270 	 */
5271 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
5272 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
5273 		return -EINVAL;
5274 
5275 	if (asoc) {
5276 		/* Fetch association values. */
5277 		if (asoc->param_flags & SPP_SACKDELAY_ENABLE) {
5278 			params.sack_delay = jiffies_to_msecs(
5279 				asoc->sackdelay);
5280 			params.sack_freq = asoc->sackfreq;
5281 
5282 		} else {
5283 			params.sack_delay = 0;
5284 			params.sack_freq = 1;
5285 		}
5286 	} else {
5287 		/* Fetch socket values. */
5288 		if (sp->param_flags & SPP_SACKDELAY_ENABLE) {
5289 			params.sack_delay  = sp->sackdelay;
5290 			params.sack_freq = sp->sackfreq;
5291 		} else {
5292 			params.sack_delay  = 0;
5293 			params.sack_freq = 1;
5294 		}
5295 	}
5296 
5297 	if (copy_to_user(optval, &params, len))
5298 		return -EFAULT;
5299 
5300 	if (put_user(len, optlen))
5301 		return -EFAULT;
5302 
5303 	return 0;
5304 }
5305 
5306 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
5307  *
5308  * Applications can specify protocol parameters for the default association
5309  * initialization.  The option name argument to setsockopt() and getsockopt()
5310  * is SCTP_INITMSG.
5311  *
5312  * Setting initialization parameters is effective only on an unconnected
5313  * socket (for UDP-style sockets only future associations are effected
5314  * by the change).  With TCP-style sockets, this option is inherited by
5315  * sockets derived from a listener socket.
5316  */
5317 static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
5318 {
5319 	if (len < sizeof(struct sctp_initmsg))
5320 		return -EINVAL;
5321 	len = sizeof(struct sctp_initmsg);
5322 	if (put_user(len, optlen))
5323 		return -EFAULT;
5324 	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
5325 		return -EFAULT;
5326 	return 0;
5327 }
5328 
5329 
5330 static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
5331 				      char __user *optval, int __user *optlen)
5332 {
5333 	struct sctp_association *asoc;
5334 	int cnt = 0;
5335 	struct sctp_getaddrs getaddrs;
5336 	struct sctp_transport *from;
5337 	void __user *to;
5338 	union sctp_addr temp;
5339 	struct sctp_sock *sp = sctp_sk(sk);
5340 	int addrlen;
5341 	size_t space_left;
5342 	int bytes_copied;
5343 
5344 	if (len < sizeof(struct sctp_getaddrs))
5345 		return -EINVAL;
5346 
5347 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
5348 		return -EFAULT;
5349 
5350 	/* For UDP-style sockets, id specifies the association to query.  */
5351 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
5352 	if (!asoc)
5353 		return -EINVAL;
5354 
5355 	to = optval + offsetof(struct sctp_getaddrs, addrs);
5356 	space_left = len - offsetof(struct sctp_getaddrs, addrs);
5357 
5358 	list_for_each_entry(from, &asoc->peer.transport_addr_list,
5359 				transports) {
5360 		memcpy(&temp, &from->ipaddr, sizeof(temp));
5361 		addrlen = sctp_get_pf_specific(sk->sk_family)
5362 			      ->addr_to_user(sp, &temp);
5363 		if (space_left < addrlen)
5364 			return -ENOMEM;
5365 		if (copy_to_user(to, &temp, addrlen))
5366 			return -EFAULT;
5367 		to += addrlen;
5368 		cnt++;
5369 		space_left -= addrlen;
5370 	}
5371 
5372 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
5373 		return -EFAULT;
5374 	bytes_copied = ((char __user *)to) - optval;
5375 	if (put_user(bytes_copied, optlen))
5376 		return -EFAULT;
5377 
5378 	return 0;
5379 }
5380 
5381 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
5382 			    size_t space_left, int *bytes_copied)
5383 {
5384 	struct sctp_sockaddr_entry *addr;
5385 	union sctp_addr temp;
5386 	int cnt = 0;
5387 	int addrlen;
5388 	struct net *net = sock_net(sk);
5389 
5390 	rcu_read_lock();
5391 	list_for_each_entry_rcu(addr, &net->sctp.local_addr_list, list) {
5392 		if (!addr->valid)
5393 			continue;
5394 
5395 		if ((PF_INET == sk->sk_family) &&
5396 		    (AF_INET6 == addr->a.sa.sa_family))
5397 			continue;
5398 		if ((PF_INET6 == sk->sk_family) &&
5399 		    inet_v6_ipv6only(sk) &&
5400 		    (AF_INET == addr->a.sa.sa_family))
5401 			continue;
5402 		memcpy(&temp, &addr->a, sizeof(temp));
5403 		if (!temp.v4.sin_port)
5404 			temp.v4.sin_port = htons(port);
5405 
5406 		addrlen = sctp_get_pf_specific(sk->sk_family)
5407 			      ->addr_to_user(sctp_sk(sk), &temp);
5408 
5409 		if (space_left < addrlen) {
5410 			cnt =  -ENOMEM;
5411 			break;
5412 		}
5413 		memcpy(to, &temp, addrlen);
5414 
5415 		to += addrlen;
5416 		cnt++;
5417 		space_left -= addrlen;
5418 		*bytes_copied += addrlen;
5419 	}
5420 	rcu_read_unlock();
5421 
5422 	return cnt;
5423 }
5424 
5425 
5426 static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
5427 				       char __user *optval, int __user *optlen)
5428 {
5429 	struct sctp_bind_addr *bp;
5430 	struct sctp_association *asoc;
5431 	int cnt = 0;
5432 	struct sctp_getaddrs getaddrs;
5433 	struct sctp_sockaddr_entry *addr;
5434 	void __user *to;
5435 	union sctp_addr temp;
5436 	struct sctp_sock *sp = sctp_sk(sk);
5437 	int addrlen;
5438 	int err = 0;
5439 	size_t space_left;
5440 	int bytes_copied = 0;
5441 	void *addrs;
5442 	void *buf;
5443 
5444 	if (len < sizeof(struct sctp_getaddrs))
5445 		return -EINVAL;
5446 
5447 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
5448 		return -EFAULT;
5449 
5450 	/*
5451 	 *  For UDP-style sockets, id specifies the association to query.
5452 	 *  If the id field is set to the value '0' then the locally bound
5453 	 *  addresses are returned without regard to any particular
5454 	 *  association.
5455 	 */
5456 	if (0 == getaddrs.assoc_id) {
5457 		bp = &sctp_sk(sk)->ep->base.bind_addr;
5458 	} else {
5459 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
5460 		if (!asoc)
5461 			return -EINVAL;
5462 		bp = &asoc->base.bind_addr;
5463 	}
5464 
5465 	to = optval + offsetof(struct sctp_getaddrs, addrs);
5466 	space_left = len - offsetof(struct sctp_getaddrs, addrs);
5467 
5468 	addrs = kmalloc(space_left, GFP_USER | __GFP_NOWARN);
5469 	if (!addrs)
5470 		return -ENOMEM;
5471 
5472 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
5473 	 * addresses from the global local address list.
5474 	 */
5475 	if (sctp_list_single_entry(&bp->address_list)) {
5476 		addr = list_entry(bp->address_list.next,
5477 				  struct sctp_sockaddr_entry, list);
5478 		if (sctp_is_any(sk, &addr->a)) {
5479 			cnt = sctp_copy_laddrs(sk, bp->port, addrs,
5480 						space_left, &bytes_copied);
5481 			if (cnt < 0) {
5482 				err = cnt;
5483 				goto out;
5484 			}
5485 			goto copy_getaddrs;
5486 		}
5487 	}
5488 
5489 	buf = addrs;
5490 	/* Protection on the bound address list is not needed since
5491 	 * in the socket option context we hold a socket lock and
5492 	 * thus the bound address list can't change.
5493 	 */
5494 	list_for_each_entry(addr, &bp->address_list, list) {
5495 		memcpy(&temp, &addr->a, sizeof(temp));
5496 		addrlen = sctp_get_pf_specific(sk->sk_family)
5497 			      ->addr_to_user(sp, &temp);
5498 		if (space_left < addrlen) {
5499 			err =  -ENOMEM; /*fixme: right error?*/
5500 			goto out;
5501 		}
5502 		memcpy(buf, &temp, addrlen);
5503 		buf += addrlen;
5504 		bytes_copied += addrlen;
5505 		cnt++;
5506 		space_left -= addrlen;
5507 	}
5508 
5509 copy_getaddrs:
5510 	if (copy_to_user(to, addrs, bytes_copied)) {
5511 		err = -EFAULT;
5512 		goto out;
5513 	}
5514 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num)) {
5515 		err = -EFAULT;
5516 		goto out;
5517 	}
5518 	if (put_user(bytes_copied, optlen))
5519 		err = -EFAULT;
5520 out:
5521 	kfree(addrs);
5522 	return err;
5523 }
5524 
5525 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
5526  *
5527  * Requests that the local SCTP stack use the enclosed peer address as
5528  * the association primary.  The enclosed address must be one of the
5529  * association peer's addresses.
5530  */
5531 static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
5532 					char __user *optval, int __user *optlen)
5533 {
5534 	struct sctp_prim prim;
5535 	struct sctp_association *asoc;
5536 	struct sctp_sock *sp = sctp_sk(sk);
5537 
5538 	if (len < sizeof(struct sctp_prim))
5539 		return -EINVAL;
5540 
5541 	len = sizeof(struct sctp_prim);
5542 
5543 	if (copy_from_user(&prim, optval, len))
5544 		return -EFAULT;
5545 
5546 	asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
5547 	if (!asoc)
5548 		return -EINVAL;
5549 
5550 	if (!asoc->peer.primary_path)
5551 		return -ENOTCONN;
5552 
5553 	memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
5554 		asoc->peer.primary_path->af_specific->sockaddr_len);
5555 
5556 	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sp,
5557 			(union sctp_addr *)&prim.ssp_addr);
5558 
5559 	if (put_user(len, optlen))
5560 		return -EFAULT;
5561 	if (copy_to_user(optval, &prim, len))
5562 		return -EFAULT;
5563 
5564 	return 0;
5565 }
5566 
5567 /*
5568  * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
5569  *
5570  * Requests that the local endpoint set the specified Adaptation Layer
5571  * Indication parameter for all future INIT and INIT-ACK exchanges.
5572  */
5573 static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
5574 				  char __user *optval, int __user *optlen)
5575 {
5576 	struct sctp_setadaptation adaptation;
5577 
5578 	if (len < sizeof(struct sctp_setadaptation))
5579 		return -EINVAL;
5580 
5581 	len = sizeof(struct sctp_setadaptation);
5582 
5583 	adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
5584 
5585 	if (put_user(len, optlen))
5586 		return -EFAULT;
5587 	if (copy_to_user(optval, &adaptation, len))
5588 		return -EFAULT;
5589 
5590 	return 0;
5591 }
5592 
5593 /*
5594  *
5595  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
5596  *
5597  *   Applications that wish to use the sendto() system call may wish to
5598  *   specify a default set of parameters that would normally be supplied
5599  *   through the inclusion of ancillary data.  This socket option allows
5600  *   such an application to set the default sctp_sndrcvinfo structure.
5601 
5602 
5603  *   The application that wishes to use this socket option simply passes
5604  *   in to this call the sctp_sndrcvinfo structure defined in Section
5605  *   5.2.2) The input parameters accepted by this call include
5606  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
5607  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
5608  *   to this call if the caller is using the UDP model.
5609  *
5610  *   For getsockopt, it get the default sctp_sndrcvinfo structure.
5611  */
5612 static int sctp_getsockopt_default_send_param(struct sock *sk,
5613 					int len, char __user *optval,
5614 					int __user *optlen)
5615 {
5616 	struct sctp_sock *sp = sctp_sk(sk);
5617 	struct sctp_association *asoc;
5618 	struct sctp_sndrcvinfo info;
5619 
5620 	if (len < sizeof(info))
5621 		return -EINVAL;
5622 
5623 	len = sizeof(info);
5624 
5625 	if (copy_from_user(&info, optval, len))
5626 		return -EFAULT;
5627 
5628 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
5629 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
5630 		return -EINVAL;
5631 	if (asoc) {
5632 		info.sinfo_stream = asoc->default_stream;
5633 		info.sinfo_flags = asoc->default_flags;
5634 		info.sinfo_ppid = asoc->default_ppid;
5635 		info.sinfo_context = asoc->default_context;
5636 		info.sinfo_timetolive = asoc->default_timetolive;
5637 	} else {
5638 		info.sinfo_stream = sp->default_stream;
5639 		info.sinfo_flags = sp->default_flags;
5640 		info.sinfo_ppid = sp->default_ppid;
5641 		info.sinfo_context = sp->default_context;
5642 		info.sinfo_timetolive = sp->default_timetolive;
5643 	}
5644 
5645 	if (put_user(len, optlen))
5646 		return -EFAULT;
5647 	if (copy_to_user(optval, &info, len))
5648 		return -EFAULT;
5649 
5650 	return 0;
5651 }
5652 
5653 /* RFC6458, Section 8.1.31. Set/get Default Send Parameters
5654  * (SCTP_DEFAULT_SNDINFO)
5655  */
5656 static int sctp_getsockopt_default_sndinfo(struct sock *sk, int len,
5657 					   char __user *optval,
5658 					   int __user *optlen)
5659 {
5660 	struct sctp_sock *sp = sctp_sk(sk);
5661 	struct sctp_association *asoc;
5662 	struct sctp_sndinfo info;
5663 
5664 	if (len < sizeof(info))
5665 		return -EINVAL;
5666 
5667 	len = sizeof(info);
5668 
5669 	if (copy_from_user(&info, optval, len))
5670 		return -EFAULT;
5671 
5672 	asoc = sctp_id2assoc(sk, info.snd_assoc_id);
5673 	if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
5674 		return -EINVAL;
5675 	if (asoc) {
5676 		info.snd_sid = asoc->default_stream;
5677 		info.snd_flags = asoc->default_flags;
5678 		info.snd_ppid = asoc->default_ppid;
5679 		info.snd_context = asoc->default_context;
5680 	} else {
5681 		info.snd_sid = sp->default_stream;
5682 		info.snd_flags = sp->default_flags;
5683 		info.snd_ppid = sp->default_ppid;
5684 		info.snd_context = sp->default_context;
5685 	}
5686 
5687 	if (put_user(len, optlen))
5688 		return -EFAULT;
5689 	if (copy_to_user(optval, &info, len))
5690 		return -EFAULT;
5691 
5692 	return 0;
5693 }
5694 
5695 /*
5696  *
5697  * 7.1.5 SCTP_NODELAY
5698  *
5699  * Turn on/off any Nagle-like algorithm.  This means that packets are
5700  * generally sent as soon as possible and no unnecessary delays are
5701  * introduced, at the cost of more packets in the network.  Expects an
5702  * integer boolean flag.
5703  */
5704 
5705 static int sctp_getsockopt_nodelay(struct sock *sk, int len,
5706 				   char __user *optval, int __user *optlen)
5707 {
5708 	int val;
5709 
5710 	if (len < sizeof(int))
5711 		return -EINVAL;
5712 
5713 	len = sizeof(int);
5714 	val = (sctp_sk(sk)->nodelay == 1);
5715 	if (put_user(len, optlen))
5716 		return -EFAULT;
5717 	if (copy_to_user(optval, &val, len))
5718 		return -EFAULT;
5719 	return 0;
5720 }
5721 
5722 /*
5723  *
5724  * 7.1.1 SCTP_RTOINFO
5725  *
5726  * The protocol parameters used to initialize and bound retransmission
5727  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
5728  * and modify these parameters.
5729  * All parameters are time values, in milliseconds.  A value of 0, when
5730  * modifying the parameters, indicates that the current value should not
5731  * be changed.
5732  *
5733  */
5734 static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
5735 				char __user *optval,
5736 				int __user *optlen) {
5737 	struct sctp_rtoinfo rtoinfo;
5738 	struct sctp_association *asoc;
5739 
5740 	if (len < sizeof (struct sctp_rtoinfo))
5741 		return -EINVAL;
5742 
5743 	len = sizeof(struct sctp_rtoinfo);
5744 
5745 	if (copy_from_user(&rtoinfo, optval, len))
5746 		return -EFAULT;
5747 
5748 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
5749 
5750 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
5751 		return -EINVAL;
5752 
5753 	/* Values corresponding to the specific association. */
5754 	if (asoc) {
5755 		rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
5756 		rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
5757 		rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
5758 	} else {
5759 		/* Values corresponding to the endpoint. */
5760 		struct sctp_sock *sp = sctp_sk(sk);
5761 
5762 		rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
5763 		rtoinfo.srto_max = sp->rtoinfo.srto_max;
5764 		rtoinfo.srto_min = sp->rtoinfo.srto_min;
5765 	}
5766 
5767 	if (put_user(len, optlen))
5768 		return -EFAULT;
5769 
5770 	if (copy_to_user(optval, &rtoinfo, len))
5771 		return -EFAULT;
5772 
5773 	return 0;
5774 }
5775 
5776 /*
5777  *
5778  * 7.1.2 SCTP_ASSOCINFO
5779  *
5780  * This option is used to tune the maximum retransmission attempts
5781  * of the association.
5782  * Returns an error if the new association retransmission value is
5783  * greater than the sum of the retransmission value  of the peer.
5784  * See [SCTP] for more information.
5785  *
5786  */
5787 static int sctp_getsockopt_associnfo(struct sock *sk, int len,
5788 				     char __user *optval,
5789 				     int __user *optlen)
5790 {
5791 
5792 	struct sctp_assocparams assocparams;
5793 	struct sctp_association *asoc;
5794 	struct list_head *pos;
5795 	int cnt = 0;
5796 
5797 	if (len < sizeof (struct sctp_assocparams))
5798 		return -EINVAL;
5799 
5800 	len = sizeof(struct sctp_assocparams);
5801 
5802 	if (copy_from_user(&assocparams, optval, len))
5803 		return -EFAULT;
5804 
5805 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
5806 
5807 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
5808 		return -EINVAL;
5809 
5810 	/* Values correspoinding to the specific association */
5811 	if (asoc) {
5812 		assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
5813 		assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
5814 		assocparams.sasoc_local_rwnd = asoc->a_rwnd;
5815 		assocparams.sasoc_cookie_life = ktime_to_ms(asoc->cookie_life);
5816 
5817 		list_for_each(pos, &asoc->peer.transport_addr_list) {
5818 			cnt++;
5819 		}
5820 
5821 		assocparams.sasoc_number_peer_destinations = cnt;
5822 	} else {
5823 		/* Values corresponding to the endpoint */
5824 		struct sctp_sock *sp = sctp_sk(sk);
5825 
5826 		assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
5827 		assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
5828 		assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
5829 		assocparams.sasoc_cookie_life =
5830 					sp->assocparams.sasoc_cookie_life;
5831 		assocparams.sasoc_number_peer_destinations =
5832 					sp->assocparams.
5833 					sasoc_number_peer_destinations;
5834 	}
5835 
5836 	if (put_user(len, optlen))
5837 		return -EFAULT;
5838 
5839 	if (copy_to_user(optval, &assocparams, len))
5840 		return -EFAULT;
5841 
5842 	return 0;
5843 }
5844 
5845 /*
5846  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
5847  *
5848  * This socket option is a boolean flag which turns on or off mapped V4
5849  * addresses.  If this option is turned on and the socket is type
5850  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
5851  * If this option is turned off, then no mapping will be done of V4
5852  * addresses and a user will receive both PF_INET6 and PF_INET type
5853  * addresses on the socket.
5854  */
5855 static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
5856 				    char __user *optval, int __user *optlen)
5857 {
5858 	int val;
5859 	struct sctp_sock *sp = sctp_sk(sk);
5860 
5861 	if (len < sizeof(int))
5862 		return -EINVAL;
5863 
5864 	len = sizeof(int);
5865 	val = sp->v4mapped;
5866 	if (put_user(len, optlen))
5867 		return -EFAULT;
5868 	if (copy_to_user(optval, &val, len))
5869 		return -EFAULT;
5870 
5871 	return 0;
5872 }
5873 
5874 /*
5875  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
5876  * (chapter and verse is quoted at sctp_setsockopt_context())
5877  */
5878 static int sctp_getsockopt_context(struct sock *sk, int len,
5879 				   char __user *optval, int __user *optlen)
5880 {
5881 	struct sctp_assoc_value params;
5882 	struct sctp_sock *sp;
5883 	struct sctp_association *asoc;
5884 
5885 	if (len < sizeof(struct sctp_assoc_value))
5886 		return -EINVAL;
5887 
5888 	len = sizeof(struct sctp_assoc_value);
5889 
5890 	if (copy_from_user(&params, optval, len))
5891 		return -EFAULT;
5892 
5893 	sp = sctp_sk(sk);
5894 
5895 	if (params.assoc_id != 0) {
5896 		asoc = sctp_id2assoc(sk, params.assoc_id);
5897 		if (!asoc)
5898 			return -EINVAL;
5899 		params.assoc_value = asoc->default_rcv_context;
5900 	} else {
5901 		params.assoc_value = sp->default_rcv_context;
5902 	}
5903 
5904 	if (put_user(len, optlen))
5905 		return -EFAULT;
5906 	if (copy_to_user(optval, &params, len))
5907 		return -EFAULT;
5908 
5909 	return 0;
5910 }
5911 
5912 /*
5913  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
5914  * This option will get or set the maximum size to put in any outgoing
5915  * SCTP DATA chunk.  If a message is larger than this size it will be
5916  * fragmented by SCTP into the specified size.  Note that the underlying
5917  * SCTP implementation may fragment into smaller sized chunks when the
5918  * PMTU of the underlying association is smaller than the value set by
5919  * the user.  The default value for this option is '0' which indicates
5920  * the user is NOT limiting fragmentation and only the PMTU will effect
5921  * SCTP's choice of DATA chunk size.  Note also that values set larger
5922  * than the maximum size of an IP datagram will effectively let SCTP
5923  * control fragmentation (i.e. the same as setting this option to 0).
5924  *
5925  * The following structure is used to access and modify this parameter:
5926  *
5927  * struct sctp_assoc_value {
5928  *   sctp_assoc_t assoc_id;
5929  *   uint32_t assoc_value;
5930  * };
5931  *
5932  * assoc_id:  This parameter is ignored for one-to-one style sockets.
5933  *    For one-to-many style sockets this parameter indicates which
5934  *    association the user is performing an action upon.  Note that if
5935  *    this field's value is zero then the endpoints default value is
5936  *    changed (effecting future associations only).
5937  * assoc_value:  This parameter specifies the maximum size in bytes.
5938  */
5939 static int sctp_getsockopt_maxseg(struct sock *sk, int len,
5940 				  char __user *optval, int __user *optlen)
5941 {
5942 	struct sctp_assoc_value params;
5943 	struct sctp_association *asoc;
5944 
5945 	if (len == sizeof(int)) {
5946 		pr_warn_ratelimited(DEPRECATED
5947 				    "%s (pid %d) "
5948 				    "Use of int in maxseg socket option.\n"
5949 				    "Use struct sctp_assoc_value instead\n",
5950 				    current->comm, task_pid_nr(current));
5951 		params.assoc_id = 0;
5952 	} else if (len >= sizeof(struct sctp_assoc_value)) {
5953 		len = sizeof(struct sctp_assoc_value);
5954 		if (copy_from_user(&params, optval, sizeof(params)))
5955 			return -EFAULT;
5956 	} else
5957 		return -EINVAL;
5958 
5959 	asoc = sctp_id2assoc(sk, params.assoc_id);
5960 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
5961 		return -EINVAL;
5962 
5963 	if (asoc)
5964 		params.assoc_value = asoc->frag_point;
5965 	else
5966 		params.assoc_value = sctp_sk(sk)->user_frag;
5967 
5968 	if (put_user(len, optlen))
5969 		return -EFAULT;
5970 	if (len == sizeof(int)) {
5971 		if (copy_to_user(optval, &params.assoc_value, len))
5972 			return -EFAULT;
5973 	} else {
5974 		if (copy_to_user(optval, &params, len))
5975 			return -EFAULT;
5976 	}
5977 
5978 	return 0;
5979 }
5980 
5981 /*
5982  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
5983  * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
5984  */
5985 static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
5986 					       char __user *optval, int __user *optlen)
5987 {
5988 	int val;
5989 
5990 	if (len < sizeof(int))
5991 		return -EINVAL;
5992 
5993 	len = sizeof(int);
5994 
5995 	val = sctp_sk(sk)->frag_interleave;
5996 	if (put_user(len, optlen))
5997 		return -EFAULT;
5998 	if (copy_to_user(optval, &val, len))
5999 		return -EFAULT;
6000 
6001 	return 0;
6002 }
6003 
6004 /*
6005  * 7.1.25.  Set or Get the sctp partial delivery point
6006  * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
6007  */
6008 static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
6009 						  char __user *optval,
6010 						  int __user *optlen)
6011 {
6012 	u32 val;
6013 
6014 	if (len < sizeof(u32))
6015 		return -EINVAL;
6016 
6017 	len = sizeof(u32);
6018 
6019 	val = sctp_sk(sk)->pd_point;
6020 	if (put_user(len, optlen))
6021 		return -EFAULT;
6022 	if (copy_to_user(optval, &val, len))
6023 		return -EFAULT;
6024 
6025 	return 0;
6026 }
6027 
6028 /*
6029  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
6030  * (chapter and verse is quoted at sctp_setsockopt_maxburst())
6031  */
6032 static int sctp_getsockopt_maxburst(struct sock *sk, int len,
6033 				    char __user *optval,
6034 				    int __user *optlen)
6035 {
6036 	struct sctp_assoc_value params;
6037 	struct sctp_sock *sp;
6038 	struct sctp_association *asoc;
6039 
6040 	if (len == sizeof(int)) {
6041 		pr_warn_ratelimited(DEPRECATED
6042 				    "%s (pid %d) "
6043 				    "Use of int in max_burst socket option.\n"
6044 				    "Use struct sctp_assoc_value instead\n",
6045 				    current->comm, task_pid_nr(current));
6046 		params.assoc_id = 0;
6047 	} else if (len >= sizeof(struct sctp_assoc_value)) {
6048 		len = sizeof(struct sctp_assoc_value);
6049 		if (copy_from_user(&params, optval, len))
6050 			return -EFAULT;
6051 	} else
6052 		return -EINVAL;
6053 
6054 	sp = sctp_sk(sk);
6055 
6056 	if (params.assoc_id != 0) {
6057 		asoc = sctp_id2assoc(sk, params.assoc_id);
6058 		if (!asoc)
6059 			return -EINVAL;
6060 		params.assoc_value = asoc->max_burst;
6061 	} else
6062 		params.assoc_value = sp->max_burst;
6063 
6064 	if (len == sizeof(int)) {
6065 		if (copy_to_user(optval, &params.assoc_value, len))
6066 			return -EFAULT;
6067 	} else {
6068 		if (copy_to_user(optval, &params, len))
6069 			return -EFAULT;
6070 	}
6071 
6072 	return 0;
6073 
6074 }
6075 
6076 static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
6077 				    char __user *optval, int __user *optlen)
6078 {
6079 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
6080 	struct sctp_hmacalgo  __user *p = (void __user *)optval;
6081 	struct sctp_hmac_algo_param *hmacs;
6082 	__u16 data_len = 0;
6083 	u32 num_idents;
6084 	int i;
6085 
6086 	if (!ep->auth_enable)
6087 		return -EACCES;
6088 
6089 	hmacs = ep->auth_hmacs_list;
6090 	data_len = ntohs(hmacs->param_hdr.length) -
6091 		   sizeof(struct sctp_paramhdr);
6092 
6093 	if (len < sizeof(struct sctp_hmacalgo) + data_len)
6094 		return -EINVAL;
6095 
6096 	len = sizeof(struct sctp_hmacalgo) + data_len;
6097 	num_idents = data_len / sizeof(u16);
6098 
6099 	if (put_user(len, optlen))
6100 		return -EFAULT;
6101 	if (put_user(num_idents, &p->shmac_num_idents))
6102 		return -EFAULT;
6103 	for (i = 0; i < num_idents; i++) {
6104 		__u16 hmacid = ntohs(hmacs->hmac_ids[i]);
6105 
6106 		if (copy_to_user(&p->shmac_idents[i], &hmacid, sizeof(__u16)))
6107 			return -EFAULT;
6108 	}
6109 	return 0;
6110 }
6111 
6112 static int sctp_getsockopt_active_key(struct sock *sk, int len,
6113 				    char __user *optval, int __user *optlen)
6114 {
6115 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
6116 	struct sctp_authkeyid val;
6117 	struct sctp_association *asoc;
6118 
6119 	if (!ep->auth_enable)
6120 		return -EACCES;
6121 
6122 	if (len < sizeof(struct sctp_authkeyid))
6123 		return -EINVAL;
6124 	if (copy_from_user(&val, optval, sizeof(struct sctp_authkeyid)))
6125 		return -EFAULT;
6126 
6127 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
6128 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
6129 		return -EINVAL;
6130 
6131 	if (asoc)
6132 		val.scact_keynumber = asoc->active_key_id;
6133 	else
6134 		val.scact_keynumber = ep->active_key_id;
6135 
6136 	len = sizeof(struct sctp_authkeyid);
6137 	if (put_user(len, optlen))
6138 		return -EFAULT;
6139 	if (copy_to_user(optval, &val, len))
6140 		return -EFAULT;
6141 
6142 	return 0;
6143 }
6144 
6145 static int sctp_getsockopt_peer_auth_chunks(struct sock *sk, int len,
6146 				    char __user *optval, int __user *optlen)
6147 {
6148 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
6149 	struct sctp_authchunks __user *p = (void __user *)optval;
6150 	struct sctp_authchunks val;
6151 	struct sctp_association *asoc;
6152 	struct sctp_chunks_param *ch;
6153 	u32    num_chunks = 0;
6154 	char __user *to;
6155 
6156 	if (!ep->auth_enable)
6157 		return -EACCES;
6158 
6159 	if (len < sizeof(struct sctp_authchunks))
6160 		return -EINVAL;
6161 
6162 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
6163 		return -EFAULT;
6164 
6165 	to = p->gauth_chunks;
6166 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
6167 	if (!asoc)
6168 		return -EINVAL;
6169 
6170 	ch = asoc->peer.peer_chunks;
6171 	if (!ch)
6172 		goto num;
6173 
6174 	/* See if the user provided enough room for all the data */
6175 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(struct sctp_paramhdr);
6176 	if (len < num_chunks)
6177 		return -EINVAL;
6178 
6179 	if (copy_to_user(to, ch->chunks, num_chunks))
6180 		return -EFAULT;
6181 num:
6182 	len = sizeof(struct sctp_authchunks) + num_chunks;
6183 	if (put_user(len, optlen))
6184 		return -EFAULT;
6185 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
6186 		return -EFAULT;
6187 	return 0;
6188 }
6189 
6190 static int sctp_getsockopt_local_auth_chunks(struct sock *sk, int len,
6191 				    char __user *optval, int __user *optlen)
6192 {
6193 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
6194 	struct sctp_authchunks __user *p = (void __user *)optval;
6195 	struct sctp_authchunks val;
6196 	struct sctp_association *asoc;
6197 	struct sctp_chunks_param *ch;
6198 	u32    num_chunks = 0;
6199 	char __user *to;
6200 
6201 	if (!ep->auth_enable)
6202 		return -EACCES;
6203 
6204 	if (len < sizeof(struct sctp_authchunks))
6205 		return -EINVAL;
6206 
6207 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
6208 		return -EFAULT;
6209 
6210 	to = p->gauth_chunks;
6211 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
6212 	if (!asoc && val.gauth_assoc_id && sctp_style(sk, UDP))
6213 		return -EINVAL;
6214 
6215 	if (asoc)
6216 		ch = (struct sctp_chunks_param *)asoc->c.auth_chunks;
6217 	else
6218 		ch = ep->auth_chunk_list;
6219 
6220 	if (!ch)
6221 		goto num;
6222 
6223 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(struct sctp_paramhdr);
6224 	if (len < sizeof(struct sctp_authchunks) + num_chunks)
6225 		return -EINVAL;
6226 
6227 	if (copy_to_user(to, ch->chunks, num_chunks))
6228 		return -EFAULT;
6229 num:
6230 	len = sizeof(struct sctp_authchunks) + num_chunks;
6231 	if (put_user(len, optlen))
6232 		return -EFAULT;
6233 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
6234 		return -EFAULT;
6235 
6236 	return 0;
6237 }
6238 
6239 /*
6240  * 8.2.5.  Get the Current Number of Associations (SCTP_GET_ASSOC_NUMBER)
6241  * This option gets the current number of associations that are attached
6242  * to a one-to-many style socket.  The option value is an uint32_t.
6243  */
6244 static int sctp_getsockopt_assoc_number(struct sock *sk, int len,
6245 				    char __user *optval, int __user *optlen)
6246 {
6247 	struct sctp_sock *sp = sctp_sk(sk);
6248 	struct sctp_association *asoc;
6249 	u32 val = 0;
6250 
6251 	if (sctp_style(sk, TCP))
6252 		return -EOPNOTSUPP;
6253 
6254 	if (len < sizeof(u32))
6255 		return -EINVAL;
6256 
6257 	len = sizeof(u32);
6258 
6259 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
6260 		val++;
6261 	}
6262 
6263 	if (put_user(len, optlen))
6264 		return -EFAULT;
6265 	if (copy_to_user(optval, &val, len))
6266 		return -EFAULT;
6267 
6268 	return 0;
6269 }
6270 
6271 /*
6272  * 8.1.23 SCTP_AUTO_ASCONF
6273  * See the corresponding setsockopt entry as description
6274  */
6275 static int sctp_getsockopt_auto_asconf(struct sock *sk, int len,
6276 				   char __user *optval, int __user *optlen)
6277 {
6278 	int val = 0;
6279 
6280 	if (len < sizeof(int))
6281 		return -EINVAL;
6282 
6283 	len = sizeof(int);
6284 	if (sctp_sk(sk)->do_auto_asconf && sctp_is_ep_boundall(sk))
6285 		val = 1;
6286 	if (put_user(len, optlen))
6287 		return -EFAULT;
6288 	if (copy_to_user(optval, &val, len))
6289 		return -EFAULT;
6290 	return 0;
6291 }
6292 
6293 /*
6294  * 8.2.6. Get the Current Identifiers of Associations
6295  *        (SCTP_GET_ASSOC_ID_LIST)
6296  *
6297  * This option gets the current list of SCTP association identifiers of
6298  * the SCTP associations handled by a one-to-many style socket.
6299  */
6300 static int sctp_getsockopt_assoc_ids(struct sock *sk, int len,
6301 				    char __user *optval, int __user *optlen)
6302 {
6303 	struct sctp_sock *sp = sctp_sk(sk);
6304 	struct sctp_association *asoc;
6305 	struct sctp_assoc_ids *ids;
6306 	u32 num = 0;
6307 
6308 	if (sctp_style(sk, TCP))
6309 		return -EOPNOTSUPP;
6310 
6311 	if (len < sizeof(struct sctp_assoc_ids))
6312 		return -EINVAL;
6313 
6314 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
6315 		num++;
6316 	}
6317 
6318 	if (len < sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num)
6319 		return -EINVAL;
6320 
6321 	len = sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num;
6322 
6323 	ids = kmalloc(len, GFP_USER | __GFP_NOWARN);
6324 	if (unlikely(!ids))
6325 		return -ENOMEM;
6326 
6327 	ids->gaids_number_of_ids = num;
6328 	num = 0;
6329 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
6330 		ids->gaids_assoc_id[num++] = asoc->assoc_id;
6331 	}
6332 
6333 	if (put_user(len, optlen) || copy_to_user(optval, ids, len)) {
6334 		kfree(ids);
6335 		return -EFAULT;
6336 	}
6337 
6338 	kfree(ids);
6339 	return 0;
6340 }
6341 
6342 /*
6343  * SCTP_PEER_ADDR_THLDS
6344  *
6345  * This option allows us to fetch the partially failed threshold for one or all
6346  * transports in an association.  See Section 6.1 of:
6347  * http://www.ietf.org/id/draft-nishida-tsvwg-sctp-failover-05.txt
6348  */
6349 static int sctp_getsockopt_paddr_thresholds(struct sock *sk,
6350 					    char __user *optval,
6351 					    int len,
6352 					    int __user *optlen)
6353 {
6354 	struct sctp_paddrthlds val;
6355 	struct sctp_transport *trans;
6356 	struct sctp_association *asoc;
6357 
6358 	if (len < sizeof(struct sctp_paddrthlds))
6359 		return -EINVAL;
6360 	len = sizeof(struct sctp_paddrthlds);
6361 	if (copy_from_user(&val, (struct sctp_paddrthlds __user *)optval, len))
6362 		return -EFAULT;
6363 
6364 	if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
6365 		asoc = sctp_id2assoc(sk, val.spt_assoc_id);
6366 		if (!asoc)
6367 			return -ENOENT;
6368 
6369 		val.spt_pathpfthld = asoc->pf_retrans;
6370 		val.spt_pathmaxrxt = asoc->pathmaxrxt;
6371 	} else {
6372 		trans = sctp_addr_id2transport(sk, &val.spt_address,
6373 					       val.spt_assoc_id);
6374 		if (!trans)
6375 			return -ENOENT;
6376 
6377 		val.spt_pathmaxrxt = trans->pathmaxrxt;
6378 		val.spt_pathpfthld = trans->pf_retrans;
6379 	}
6380 
6381 	if (put_user(len, optlen) || copy_to_user(optval, &val, len))
6382 		return -EFAULT;
6383 
6384 	return 0;
6385 }
6386 
6387 /*
6388  * SCTP_GET_ASSOC_STATS
6389  *
6390  * This option retrieves local per endpoint statistics. It is modeled
6391  * after OpenSolaris' implementation
6392  */
6393 static int sctp_getsockopt_assoc_stats(struct sock *sk, int len,
6394 				       char __user *optval,
6395 				       int __user *optlen)
6396 {
6397 	struct sctp_assoc_stats sas;
6398 	struct sctp_association *asoc = NULL;
6399 
6400 	/* User must provide at least the assoc id */
6401 	if (len < sizeof(sctp_assoc_t))
6402 		return -EINVAL;
6403 
6404 	/* Allow the struct to grow and fill in as much as possible */
6405 	len = min_t(size_t, len, sizeof(sas));
6406 
6407 	if (copy_from_user(&sas, optval, len))
6408 		return -EFAULT;
6409 
6410 	asoc = sctp_id2assoc(sk, sas.sas_assoc_id);
6411 	if (!asoc)
6412 		return -EINVAL;
6413 
6414 	sas.sas_rtxchunks = asoc->stats.rtxchunks;
6415 	sas.sas_gapcnt = asoc->stats.gapcnt;
6416 	sas.sas_outofseqtsns = asoc->stats.outofseqtsns;
6417 	sas.sas_osacks = asoc->stats.osacks;
6418 	sas.sas_isacks = asoc->stats.isacks;
6419 	sas.sas_octrlchunks = asoc->stats.octrlchunks;
6420 	sas.sas_ictrlchunks = asoc->stats.ictrlchunks;
6421 	sas.sas_oodchunks = asoc->stats.oodchunks;
6422 	sas.sas_iodchunks = asoc->stats.iodchunks;
6423 	sas.sas_ouodchunks = asoc->stats.ouodchunks;
6424 	sas.sas_iuodchunks = asoc->stats.iuodchunks;
6425 	sas.sas_idupchunks = asoc->stats.idupchunks;
6426 	sas.sas_opackets = asoc->stats.opackets;
6427 	sas.sas_ipackets = asoc->stats.ipackets;
6428 
6429 	/* New high max rto observed, will return 0 if not a single
6430 	 * RTO update took place. obs_rto_ipaddr will be bogus
6431 	 * in such a case
6432 	 */
6433 	sas.sas_maxrto = asoc->stats.max_obs_rto;
6434 	memcpy(&sas.sas_obs_rto_ipaddr, &asoc->stats.obs_rto_ipaddr,
6435 		sizeof(struct sockaddr_storage));
6436 
6437 	/* Mark beginning of a new observation period */
6438 	asoc->stats.max_obs_rto = asoc->rto_min;
6439 
6440 	if (put_user(len, optlen))
6441 		return -EFAULT;
6442 
6443 	pr_debug("%s: len:%d, assoc_id:%d\n", __func__, len, sas.sas_assoc_id);
6444 
6445 	if (copy_to_user(optval, &sas, len))
6446 		return -EFAULT;
6447 
6448 	return 0;
6449 }
6450 
6451 static int sctp_getsockopt_recvrcvinfo(struct sock *sk,	int len,
6452 				       char __user *optval,
6453 				       int __user *optlen)
6454 {
6455 	int val = 0;
6456 
6457 	if (len < sizeof(int))
6458 		return -EINVAL;
6459 
6460 	len = sizeof(int);
6461 	if (sctp_sk(sk)->recvrcvinfo)
6462 		val = 1;
6463 	if (put_user(len, optlen))
6464 		return -EFAULT;
6465 	if (copy_to_user(optval, &val, len))
6466 		return -EFAULT;
6467 
6468 	return 0;
6469 }
6470 
6471 static int sctp_getsockopt_recvnxtinfo(struct sock *sk,	int len,
6472 				       char __user *optval,
6473 				       int __user *optlen)
6474 {
6475 	int val = 0;
6476 
6477 	if (len < sizeof(int))
6478 		return -EINVAL;
6479 
6480 	len = sizeof(int);
6481 	if (sctp_sk(sk)->recvnxtinfo)
6482 		val = 1;
6483 	if (put_user(len, optlen))
6484 		return -EFAULT;
6485 	if (copy_to_user(optval, &val, len))
6486 		return -EFAULT;
6487 
6488 	return 0;
6489 }
6490 
6491 static int sctp_getsockopt_pr_supported(struct sock *sk, int len,
6492 					char __user *optval,
6493 					int __user *optlen)
6494 {
6495 	struct sctp_assoc_value params;
6496 	struct sctp_association *asoc;
6497 	int retval = -EFAULT;
6498 
6499 	if (len < sizeof(params)) {
6500 		retval = -EINVAL;
6501 		goto out;
6502 	}
6503 
6504 	len = sizeof(params);
6505 	if (copy_from_user(&params, optval, len))
6506 		goto out;
6507 
6508 	asoc = sctp_id2assoc(sk, params.assoc_id);
6509 	if (asoc) {
6510 		params.assoc_value = asoc->prsctp_enable;
6511 	} else if (!params.assoc_id) {
6512 		struct sctp_sock *sp = sctp_sk(sk);
6513 
6514 		params.assoc_value = sp->ep->prsctp_enable;
6515 	} else {
6516 		retval = -EINVAL;
6517 		goto out;
6518 	}
6519 
6520 	if (put_user(len, optlen))
6521 		goto out;
6522 
6523 	if (copy_to_user(optval, &params, len))
6524 		goto out;
6525 
6526 	retval = 0;
6527 
6528 out:
6529 	return retval;
6530 }
6531 
6532 static int sctp_getsockopt_default_prinfo(struct sock *sk, int len,
6533 					  char __user *optval,
6534 					  int __user *optlen)
6535 {
6536 	struct sctp_default_prinfo info;
6537 	struct sctp_association *asoc;
6538 	int retval = -EFAULT;
6539 
6540 	if (len < sizeof(info)) {
6541 		retval = -EINVAL;
6542 		goto out;
6543 	}
6544 
6545 	len = sizeof(info);
6546 	if (copy_from_user(&info, optval, len))
6547 		goto out;
6548 
6549 	asoc = sctp_id2assoc(sk, info.pr_assoc_id);
6550 	if (asoc) {
6551 		info.pr_policy = SCTP_PR_POLICY(asoc->default_flags);
6552 		info.pr_value = asoc->default_timetolive;
6553 	} else if (!info.pr_assoc_id) {
6554 		struct sctp_sock *sp = sctp_sk(sk);
6555 
6556 		info.pr_policy = SCTP_PR_POLICY(sp->default_flags);
6557 		info.pr_value = sp->default_timetolive;
6558 	} else {
6559 		retval = -EINVAL;
6560 		goto out;
6561 	}
6562 
6563 	if (put_user(len, optlen))
6564 		goto out;
6565 
6566 	if (copy_to_user(optval, &info, len))
6567 		goto out;
6568 
6569 	retval = 0;
6570 
6571 out:
6572 	return retval;
6573 }
6574 
6575 static int sctp_getsockopt_pr_assocstatus(struct sock *sk, int len,
6576 					  char __user *optval,
6577 					  int __user *optlen)
6578 {
6579 	struct sctp_prstatus params;
6580 	struct sctp_association *asoc;
6581 	int policy;
6582 	int retval = -EINVAL;
6583 
6584 	if (len < sizeof(params))
6585 		goto out;
6586 
6587 	len = sizeof(params);
6588 	if (copy_from_user(&params, optval, len)) {
6589 		retval = -EFAULT;
6590 		goto out;
6591 	}
6592 
6593 	policy = params.sprstat_policy;
6594 	if (policy & ~SCTP_PR_SCTP_MASK)
6595 		goto out;
6596 
6597 	asoc = sctp_id2assoc(sk, params.sprstat_assoc_id);
6598 	if (!asoc)
6599 		goto out;
6600 
6601 	if (policy == SCTP_PR_SCTP_NONE) {
6602 		params.sprstat_abandoned_unsent = 0;
6603 		params.sprstat_abandoned_sent = 0;
6604 		for (policy = 0; policy <= SCTP_PR_INDEX(MAX); policy++) {
6605 			params.sprstat_abandoned_unsent +=
6606 				asoc->abandoned_unsent[policy];
6607 			params.sprstat_abandoned_sent +=
6608 				asoc->abandoned_sent[policy];
6609 		}
6610 	} else {
6611 		params.sprstat_abandoned_unsent =
6612 			asoc->abandoned_unsent[__SCTP_PR_INDEX(policy)];
6613 		params.sprstat_abandoned_sent =
6614 			asoc->abandoned_sent[__SCTP_PR_INDEX(policy)];
6615 	}
6616 
6617 	if (put_user(len, optlen)) {
6618 		retval = -EFAULT;
6619 		goto out;
6620 	}
6621 
6622 	if (copy_to_user(optval, &params, len)) {
6623 		retval = -EFAULT;
6624 		goto out;
6625 	}
6626 
6627 	retval = 0;
6628 
6629 out:
6630 	return retval;
6631 }
6632 
6633 static int sctp_getsockopt_pr_streamstatus(struct sock *sk, int len,
6634 					   char __user *optval,
6635 					   int __user *optlen)
6636 {
6637 	struct sctp_stream_out *streamout;
6638 	struct sctp_association *asoc;
6639 	struct sctp_prstatus params;
6640 	int retval = -EINVAL;
6641 	int policy;
6642 
6643 	if (len < sizeof(params))
6644 		goto out;
6645 
6646 	len = sizeof(params);
6647 	if (copy_from_user(&params, optval, len)) {
6648 		retval = -EFAULT;
6649 		goto out;
6650 	}
6651 
6652 	policy = params.sprstat_policy;
6653 	if (policy & ~SCTP_PR_SCTP_MASK)
6654 		goto out;
6655 
6656 	asoc = sctp_id2assoc(sk, params.sprstat_assoc_id);
6657 	if (!asoc || params.sprstat_sid >= asoc->stream.outcnt)
6658 		goto out;
6659 
6660 	streamout = &asoc->stream.out[params.sprstat_sid];
6661 	if (policy == SCTP_PR_SCTP_NONE) {
6662 		params.sprstat_abandoned_unsent = 0;
6663 		params.sprstat_abandoned_sent = 0;
6664 		for (policy = 0; policy <= SCTP_PR_INDEX(MAX); policy++) {
6665 			params.sprstat_abandoned_unsent +=
6666 				streamout->abandoned_unsent[policy];
6667 			params.sprstat_abandoned_sent +=
6668 				streamout->abandoned_sent[policy];
6669 		}
6670 	} else {
6671 		params.sprstat_abandoned_unsent =
6672 			streamout->abandoned_unsent[__SCTP_PR_INDEX(policy)];
6673 		params.sprstat_abandoned_sent =
6674 			streamout->abandoned_sent[__SCTP_PR_INDEX(policy)];
6675 	}
6676 
6677 	if (put_user(len, optlen) || copy_to_user(optval, &params, len)) {
6678 		retval = -EFAULT;
6679 		goto out;
6680 	}
6681 
6682 	retval = 0;
6683 
6684 out:
6685 	return retval;
6686 }
6687 
6688 static int sctp_getsockopt_reconfig_supported(struct sock *sk, int len,
6689 					      char __user *optval,
6690 					      int __user *optlen)
6691 {
6692 	struct sctp_assoc_value params;
6693 	struct sctp_association *asoc;
6694 	int retval = -EFAULT;
6695 
6696 	if (len < sizeof(params)) {
6697 		retval = -EINVAL;
6698 		goto out;
6699 	}
6700 
6701 	len = sizeof(params);
6702 	if (copy_from_user(&params, optval, len))
6703 		goto out;
6704 
6705 	asoc = sctp_id2assoc(sk, params.assoc_id);
6706 	if (asoc) {
6707 		params.assoc_value = asoc->reconf_enable;
6708 	} else if (!params.assoc_id) {
6709 		struct sctp_sock *sp = sctp_sk(sk);
6710 
6711 		params.assoc_value = sp->ep->reconf_enable;
6712 	} else {
6713 		retval = -EINVAL;
6714 		goto out;
6715 	}
6716 
6717 	if (put_user(len, optlen))
6718 		goto out;
6719 
6720 	if (copy_to_user(optval, &params, len))
6721 		goto out;
6722 
6723 	retval = 0;
6724 
6725 out:
6726 	return retval;
6727 }
6728 
6729 static int sctp_getsockopt_enable_strreset(struct sock *sk, int len,
6730 					   char __user *optval,
6731 					   int __user *optlen)
6732 {
6733 	struct sctp_assoc_value params;
6734 	struct sctp_association *asoc;
6735 	int retval = -EFAULT;
6736 
6737 	if (len < sizeof(params)) {
6738 		retval = -EINVAL;
6739 		goto out;
6740 	}
6741 
6742 	len = sizeof(params);
6743 	if (copy_from_user(&params, optval, len))
6744 		goto out;
6745 
6746 	asoc = sctp_id2assoc(sk, params.assoc_id);
6747 	if (asoc) {
6748 		params.assoc_value = asoc->strreset_enable;
6749 	} else if (!params.assoc_id) {
6750 		struct sctp_sock *sp = sctp_sk(sk);
6751 
6752 		params.assoc_value = sp->ep->strreset_enable;
6753 	} else {
6754 		retval = -EINVAL;
6755 		goto out;
6756 	}
6757 
6758 	if (put_user(len, optlen))
6759 		goto out;
6760 
6761 	if (copy_to_user(optval, &params, len))
6762 		goto out;
6763 
6764 	retval = 0;
6765 
6766 out:
6767 	return retval;
6768 }
6769 
6770 static int sctp_getsockopt(struct sock *sk, int level, int optname,
6771 			   char __user *optval, int __user *optlen)
6772 {
6773 	int retval = 0;
6774 	int len;
6775 
6776 	pr_debug("%s: sk:%p, optname:%d\n", __func__, sk, optname);
6777 
6778 	/* I can hardly begin to describe how wrong this is.  This is
6779 	 * so broken as to be worse than useless.  The API draft
6780 	 * REALLY is NOT helpful here...  I am not convinced that the
6781 	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
6782 	 * are at all well-founded.
6783 	 */
6784 	if (level != SOL_SCTP) {
6785 		struct sctp_af *af = sctp_sk(sk)->pf->af;
6786 
6787 		retval = af->getsockopt(sk, level, optname, optval, optlen);
6788 		return retval;
6789 	}
6790 
6791 	if (get_user(len, optlen))
6792 		return -EFAULT;
6793 
6794 	if (len < 0)
6795 		return -EINVAL;
6796 
6797 	lock_sock(sk);
6798 
6799 	switch (optname) {
6800 	case SCTP_STATUS:
6801 		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
6802 		break;
6803 	case SCTP_DISABLE_FRAGMENTS:
6804 		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
6805 							   optlen);
6806 		break;
6807 	case SCTP_EVENTS:
6808 		retval = sctp_getsockopt_events(sk, len, optval, optlen);
6809 		break;
6810 	case SCTP_AUTOCLOSE:
6811 		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
6812 		break;
6813 	case SCTP_SOCKOPT_PEELOFF:
6814 		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
6815 		break;
6816 	case SCTP_SOCKOPT_PEELOFF_FLAGS:
6817 		retval = sctp_getsockopt_peeloff_flags(sk, len, optval, optlen);
6818 		break;
6819 	case SCTP_PEER_ADDR_PARAMS:
6820 		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
6821 							  optlen);
6822 		break;
6823 	case SCTP_DELAYED_SACK:
6824 		retval = sctp_getsockopt_delayed_ack(sk, len, optval,
6825 							  optlen);
6826 		break;
6827 	case SCTP_INITMSG:
6828 		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
6829 		break;
6830 	case SCTP_GET_PEER_ADDRS:
6831 		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
6832 						    optlen);
6833 		break;
6834 	case SCTP_GET_LOCAL_ADDRS:
6835 		retval = sctp_getsockopt_local_addrs(sk, len, optval,
6836 						     optlen);
6837 		break;
6838 	case SCTP_SOCKOPT_CONNECTX3:
6839 		retval = sctp_getsockopt_connectx3(sk, len, optval, optlen);
6840 		break;
6841 	case SCTP_DEFAULT_SEND_PARAM:
6842 		retval = sctp_getsockopt_default_send_param(sk, len,
6843 							    optval, optlen);
6844 		break;
6845 	case SCTP_DEFAULT_SNDINFO:
6846 		retval = sctp_getsockopt_default_sndinfo(sk, len,
6847 							 optval, optlen);
6848 		break;
6849 	case SCTP_PRIMARY_ADDR:
6850 		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
6851 		break;
6852 	case SCTP_NODELAY:
6853 		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
6854 		break;
6855 	case SCTP_RTOINFO:
6856 		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
6857 		break;
6858 	case SCTP_ASSOCINFO:
6859 		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
6860 		break;
6861 	case SCTP_I_WANT_MAPPED_V4_ADDR:
6862 		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
6863 		break;
6864 	case SCTP_MAXSEG:
6865 		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
6866 		break;
6867 	case SCTP_GET_PEER_ADDR_INFO:
6868 		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
6869 							optlen);
6870 		break;
6871 	case SCTP_ADAPTATION_LAYER:
6872 		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
6873 							optlen);
6874 		break;
6875 	case SCTP_CONTEXT:
6876 		retval = sctp_getsockopt_context(sk, len, optval, optlen);
6877 		break;
6878 	case SCTP_FRAGMENT_INTERLEAVE:
6879 		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
6880 							     optlen);
6881 		break;
6882 	case SCTP_PARTIAL_DELIVERY_POINT:
6883 		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
6884 								optlen);
6885 		break;
6886 	case SCTP_MAX_BURST:
6887 		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
6888 		break;
6889 	case SCTP_AUTH_KEY:
6890 	case SCTP_AUTH_CHUNK:
6891 	case SCTP_AUTH_DELETE_KEY:
6892 		retval = -EOPNOTSUPP;
6893 		break;
6894 	case SCTP_HMAC_IDENT:
6895 		retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
6896 		break;
6897 	case SCTP_AUTH_ACTIVE_KEY:
6898 		retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
6899 		break;
6900 	case SCTP_PEER_AUTH_CHUNKS:
6901 		retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
6902 							optlen);
6903 		break;
6904 	case SCTP_LOCAL_AUTH_CHUNKS:
6905 		retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
6906 							optlen);
6907 		break;
6908 	case SCTP_GET_ASSOC_NUMBER:
6909 		retval = sctp_getsockopt_assoc_number(sk, len, optval, optlen);
6910 		break;
6911 	case SCTP_GET_ASSOC_ID_LIST:
6912 		retval = sctp_getsockopt_assoc_ids(sk, len, optval, optlen);
6913 		break;
6914 	case SCTP_AUTO_ASCONF:
6915 		retval = sctp_getsockopt_auto_asconf(sk, len, optval, optlen);
6916 		break;
6917 	case SCTP_PEER_ADDR_THLDS:
6918 		retval = sctp_getsockopt_paddr_thresholds(sk, optval, len, optlen);
6919 		break;
6920 	case SCTP_GET_ASSOC_STATS:
6921 		retval = sctp_getsockopt_assoc_stats(sk, len, optval, optlen);
6922 		break;
6923 	case SCTP_RECVRCVINFO:
6924 		retval = sctp_getsockopt_recvrcvinfo(sk, len, optval, optlen);
6925 		break;
6926 	case SCTP_RECVNXTINFO:
6927 		retval = sctp_getsockopt_recvnxtinfo(sk, len, optval, optlen);
6928 		break;
6929 	case SCTP_PR_SUPPORTED:
6930 		retval = sctp_getsockopt_pr_supported(sk, len, optval, optlen);
6931 		break;
6932 	case SCTP_DEFAULT_PRINFO:
6933 		retval = sctp_getsockopt_default_prinfo(sk, len, optval,
6934 							optlen);
6935 		break;
6936 	case SCTP_PR_ASSOC_STATUS:
6937 		retval = sctp_getsockopt_pr_assocstatus(sk, len, optval,
6938 							optlen);
6939 		break;
6940 	case SCTP_PR_STREAM_STATUS:
6941 		retval = sctp_getsockopt_pr_streamstatus(sk, len, optval,
6942 							 optlen);
6943 		break;
6944 	case SCTP_RECONFIG_SUPPORTED:
6945 		retval = sctp_getsockopt_reconfig_supported(sk, len, optval,
6946 							    optlen);
6947 		break;
6948 	case SCTP_ENABLE_STREAM_RESET:
6949 		retval = sctp_getsockopt_enable_strreset(sk, len, optval,
6950 							 optlen);
6951 		break;
6952 	default:
6953 		retval = -ENOPROTOOPT;
6954 		break;
6955 	}
6956 
6957 	release_sock(sk);
6958 	return retval;
6959 }
6960 
6961 static int sctp_hash(struct sock *sk)
6962 {
6963 	/* STUB */
6964 	return 0;
6965 }
6966 
6967 static void sctp_unhash(struct sock *sk)
6968 {
6969 	/* STUB */
6970 }
6971 
6972 /* Check if port is acceptable.  Possibly find first available port.
6973  *
6974  * The port hash table (contained in the 'global' SCTP protocol storage
6975  * returned by struct sctp_protocol *sctp_get_protocol()). The hash
6976  * table is an array of 4096 lists (sctp_bind_hashbucket). Each
6977  * list (the list number is the port number hashed out, so as you
6978  * would expect from a hash function, all the ports in a given list have
6979  * such a number that hashes out to the same list number; you were
6980  * expecting that, right?); so each list has a set of ports, with a
6981  * link to the socket (struct sock) that uses it, the port number and
6982  * a fastreuse flag (FIXME: NPI ipg).
6983  */
6984 static struct sctp_bind_bucket *sctp_bucket_create(
6985 	struct sctp_bind_hashbucket *head, struct net *, unsigned short snum);
6986 
6987 static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
6988 {
6989 	struct sctp_bind_hashbucket *head; /* hash list */
6990 	struct sctp_bind_bucket *pp;
6991 	unsigned short snum;
6992 	int ret;
6993 
6994 	snum = ntohs(addr->v4.sin_port);
6995 
6996 	pr_debug("%s: begins, snum:%d\n", __func__, snum);
6997 
6998 	local_bh_disable();
6999 
7000 	if (snum == 0) {
7001 		/* Search for an available port. */
7002 		int low, high, remaining, index;
7003 		unsigned int rover;
7004 		struct net *net = sock_net(sk);
7005 
7006 		inet_get_local_port_range(net, &low, &high);
7007 		remaining = (high - low) + 1;
7008 		rover = prandom_u32() % remaining + low;
7009 
7010 		do {
7011 			rover++;
7012 			if ((rover < low) || (rover > high))
7013 				rover = low;
7014 			if (inet_is_local_reserved_port(net, rover))
7015 				continue;
7016 			index = sctp_phashfn(sock_net(sk), rover);
7017 			head = &sctp_port_hashtable[index];
7018 			spin_lock(&head->lock);
7019 			sctp_for_each_hentry(pp, &head->chain)
7020 				if ((pp->port == rover) &&
7021 				    net_eq(sock_net(sk), pp->net))
7022 					goto next;
7023 			break;
7024 		next:
7025 			spin_unlock(&head->lock);
7026 		} while (--remaining > 0);
7027 
7028 		/* Exhausted local port range during search? */
7029 		ret = 1;
7030 		if (remaining <= 0)
7031 			goto fail;
7032 
7033 		/* OK, here is the one we will use.  HEAD (the port
7034 		 * hash table list entry) is non-NULL and we hold it's
7035 		 * mutex.
7036 		 */
7037 		snum = rover;
7038 	} else {
7039 		/* We are given an specific port number; we verify
7040 		 * that it is not being used. If it is used, we will
7041 		 * exahust the search in the hash list corresponding
7042 		 * to the port number (snum) - we detect that with the
7043 		 * port iterator, pp being NULL.
7044 		 */
7045 		head = &sctp_port_hashtable[sctp_phashfn(sock_net(sk), snum)];
7046 		spin_lock(&head->lock);
7047 		sctp_for_each_hentry(pp, &head->chain) {
7048 			if ((pp->port == snum) && net_eq(pp->net, sock_net(sk)))
7049 				goto pp_found;
7050 		}
7051 	}
7052 	pp = NULL;
7053 	goto pp_not_found;
7054 pp_found:
7055 	if (!hlist_empty(&pp->owner)) {
7056 		/* We had a port hash table hit - there is an
7057 		 * available port (pp != NULL) and it is being
7058 		 * used by other socket (pp->owner not empty); that other
7059 		 * socket is going to be sk2.
7060 		 */
7061 		int reuse = sk->sk_reuse;
7062 		struct sock *sk2;
7063 
7064 		pr_debug("%s: found a possible match\n", __func__);
7065 
7066 		if (pp->fastreuse && sk->sk_reuse &&
7067 			sk->sk_state != SCTP_SS_LISTENING)
7068 			goto success;
7069 
7070 		/* Run through the list of sockets bound to the port
7071 		 * (pp->port) [via the pointers bind_next and
7072 		 * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
7073 		 * we get the endpoint they describe and run through
7074 		 * the endpoint's list of IP (v4 or v6) addresses,
7075 		 * comparing each of the addresses with the address of
7076 		 * the socket sk. If we find a match, then that means
7077 		 * that this port/socket (sk) combination are already
7078 		 * in an endpoint.
7079 		 */
7080 		sk_for_each_bound(sk2, &pp->owner) {
7081 			struct sctp_endpoint *ep2;
7082 			ep2 = sctp_sk(sk2)->ep;
7083 
7084 			if (sk == sk2 ||
7085 			    (reuse && sk2->sk_reuse &&
7086 			     sk2->sk_state != SCTP_SS_LISTENING))
7087 				continue;
7088 
7089 			if (sctp_bind_addr_conflict(&ep2->base.bind_addr, addr,
7090 						 sctp_sk(sk2), sctp_sk(sk))) {
7091 				ret = (long)sk2;
7092 				goto fail_unlock;
7093 			}
7094 		}
7095 
7096 		pr_debug("%s: found a match\n", __func__);
7097 	}
7098 pp_not_found:
7099 	/* If there was a hash table miss, create a new port.  */
7100 	ret = 1;
7101 	if (!pp && !(pp = sctp_bucket_create(head, sock_net(sk), snum)))
7102 		goto fail_unlock;
7103 
7104 	/* In either case (hit or miss), make sure fastreuse is 1 only
7105 	 * if sk->sk_reuse is too (that is, if the caller requested
7106 	 * SO_REUSEADDR on this socket -sk-).
7107 	 */
7108 	if (hlist_empty(&pp->owner)) {
7109 		if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
7110 			pp->fastreuse = 1;
7111 		else
7112 			pp->fastreuse = 0;
7113 	} else if (pp->fastreuse &&
7114 		(!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
7115 		pp->fastreuse = 0;
7116 
7117 	/* We are set, so fill up all the data in the hash table
7118 	 * entry, tie the socket list information with the rest of the
7119 	 * sockets FIXME: Blurry, NPI (ipg).
7120 	 */
7121 success:
7122 	if (!sctp_sk(sk)->bind_hash) {
7123 		inet_sk(sk)->inet_num = snum;
7124 		sk_add_bind_node(sk, &pp->owner);
7125 		sctp_sk(sk)->bind_hash = pp;
7126 	}
7127 	ret = 0;
7128 
7129 fail_unlock:
7130 	spin_unlock(&head->lock);
7131 
7132 fail:
7133 	local_bh_enable();
7134 	return ret;
7135 }
7136 
7137 /* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
7138  * port is requested.
7139  */
7140 static int sctp_get_port(struct sock *sk, unsigned short snum)
7141 {
7142 	union sctp_addr addr;
7143 	struct sctp_af *af = sctp_sk(sk)->pf->af;
7144 
7145 	/* Set up a dummy address struct from the sk. */
7146 	af->from_sk(&addr, sk);
7147 	addr.v4.sin_port = htons(snum);
7148 
7149 	/* Note: sk->sk_num gets filled in if ephemeral port request. */
7150 	return !!sctp_get_port_local(sk, &addr);
7151 }
7152 
7153 /*
7154  *  Move a socket to LISTENING state.
7155  */
7156 static int sctp_listen_start(struct sock *sk, int backlog)
7157 {
7158 	struct sctp_sock *sp = sctp_sk(sk);
7159 	struct sctp_endpoint *ep = sp->ep;
7160 	struct crypto_shash *tfm = NULL;
7161 	char alg[32];
7162 
7163 	/* Allocate HMAC for generating cookie. */
7164 	if (!sp->hmac && sp->sctp_hmac_alg) {
7165 		sprintf(alg, "hmac(%s)", sp->sctp_hmac_alg);
7166 		tfm = crypto_alloc_shash(alg, 0, 0);
7167 		if (IS_ERR(tfm)) {
7168 			net_info_ratelimited("failed to load transform for %s: %ld\n",
7169 					     sp->sctp_hmac_alg, PTR_ERR(tfm));
7170 			return -ENOSYS;
7171 		}
7172 		sctp_sk(sk)->hmac = tfm;
7173 	}
7174 
7175 	/*
7176 	 * If a bind() or sctp_bindx() is not called prior to a listen()
7177 	 * call that allows new associations to be accepted, the system
7178 	 * picks an ephemeral port and will choose an address set equivalent
7179 	 * to binding with a wildcard address.
7180 	 *
7181 	 * This is not currently spelled out in the SCTP sockets
7182 	 * extensions draft, but follows the practice as seen in TCP
7183 	 * sockets.
7184 	 *
7185 	 */
7186 	sk->sk_state = SCTP_SS_LISTENING;
7187 	if (!ep->base.bind_addr.port) {
7188 		if (sctp_autobind(sk))
7189 			return -EAGAIN;
7190 	} else {
7191 		if (sctp_get_port(sk, inet_sk(sk)->inet_num)) {
7192 			sk->sk_state = SCTP_SS_CLOSED;
7193 			return -EADDRINUSE;
7194 		}
7195 	}
7196 
7197 	sk->sk_max_ack_backlog = backlog;
7198 	sctp_hash_endpoint(ep);
7199 	return 0;
7200 }
7201 
7202 /*
7203  * 4.1.3 / 5.1.3 listen()
7204  *
7205  *   By default, new associations are not accepted for UDP style sockets.
7206  *   An application uses listen() to mark a socket as being able to
7207  *   accept new associations.
7208  *
7209  *   On TCP style sockets, applications use listen() to ready the SCTP
7210  *   endpoint for accepting inbound associations.
7211  *
7212  *   On both types of endpoints a backlog of '0' disables listening.
7213  *
7214  *  Move a socket to LISTENING state.
7215  */
7216 int sctp_inet_listen(struct socket *sock, int backlog)
7217 {
7218 	struct sock *sk = sock->sk;
7219 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
7220 	int err = -EINVAL;
7221 
7222 	if (unlikely(backlog < 0))
7223 		return err;
7224 
7225 	lock_sock(sk);
7226 
7227 	/* Peeled-off sockets are not allowed to listen().  */
7228 	if (sctp_style(sk, UDP_HIGH_BANDWIDTH))
7229 		goto out;
7230 
7231 	if (sock->state != SS_UNCONNECTED)
7232 		goto out;
7233 
7234 	if (!sctp_sstate(sk, LISTENING) && !sctp_sstate(sk, CLOSED))
7235 		goto out;
7236 
7237 	/* If backlog is zero, disable listening. */
7238 	if (!backlog) {
7239 		if (sctp_sstate(sk, CLOSED))
7240 			goto out;
7241 
7242 		err = 0;
7243 		sctp_unhash_endpoint(ep);
7244 		sk->sk_state = SCTP_SS_CLOSED;
7245 		if (sk->sk_reuse)
7246 			sctp_sk(sk)->bind_hash->fastreuse = 1;
7247 		goto out;
7248 	}
7249 
7250 	/* If we are already listening, just update the backlog */
7251 	if (sctp_sstate(sk, LISTENING))
7252 		sk->sk_max_ack_backlog = backlog;
7253 	else {
7254 		err = sctp_listen_start(sk, backlog);
7255 		if (err)
7256 			goto out;
7257 	}
7258 
7259 	err = 0;
7260 out:
7261 	release_sock(sk);
7262 	return err;
7263 }
7264 
7265 /*
7266  * This function is done by modeling the current datagram_poll() and the
7267  * tcp_poll().  Note that, based on these implementations, we don't
7268  * lock the socket in this function, even though it seems that,
7269  * ideally, locking or some other mechanisms can be used to ensure
7270  * the integrity of the counters (sndbuf and wmem_alloc) used
7271  * in this place.  We assume that we don't need locks either until proven
7272  * otherwise.
7273  *
7274  * Another thing to note is that we include the Async I/O support
7275  * here, again, by modeling the current TCP/UDP code.  We don't have
7276  * a good way to test with it yet.
7277  */
7278 unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
7279 {
7280 	struct sock *sk = sock->sk;
7281 	struct sctp_sock *sp = sctp_sk(sk);
7282 	unsigned int mask;
7283 
7284 	poll_wait(file, sk_sleep(sk), wait);
7285 
7286 	sock_rps_record_flow(sk);
7287 
7288 	/* A TCP-style listening socket becomes readable when the accept queue
7289 	 * is not empty.
7290 	 */
7291 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
7292 		return (!list_empty(&sp->ep->asocs)) ?
7293 			(POLLIN | POLLRDNORM) : 0;
7294 
7295 	mask = 0;
7296 
7297 	/* Is there any exceptional events?  */
7298 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
7299 		mask |= POLLERR |
7300 			(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0);
7301 	if (sk->sk_shutdown & RCV_SHUTDOWN)
7302 		mask |= POLLRDHUP | POLLIN | POLLRDNORM;
7303 	if (sk->sk_shutdown == SHUTDOWN_MASK)
7304 		mask |= POLLHUP;
7305 
7306 	/* Is it readable?  Reconsider this code with TCP-style support.  */
7307 	if (!skb_queue_empty(&sk->sk_receive_queue))
7308 		mask |= POLLIN | POLLRDNORM;
7309 
7310 	/* The association is either gone or not ready.  */
7311 	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
7312 		return mask;
7313 
7314 	/* Is it writable?  */
7315 	if (sctp_writeable(sk)) {
7316 		mask |= POLLOUT | POLLWRNORM;
7317 	} else {
7318 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
7319 		/*
7320 		 * Since the socket is not locked, the buffer
7321 		 * might be made available after the writeable check and
7322 		 * before the bit is set.  This could cause a lost I/O
7323 		 * signal.  tcp_poll() has a race breaker for this race
7324 		 * condition.  Based on their implementation, we put
7325 		 * in the following code to cover it as well.
7326 		 */
7327 		if (sctp_writeable(sk))
7328 			mask |= POLLOUT | POLLWRNORM;
7329 	}
7330 	return mask;
7331 }
7332 
7333 /********************************************************************
7334  * 2nd Level Abstractions
7335  ********************************************************************/
7336 
7337 static struct sctp_bind_bucket *sctp_bucket_create(
7338 	struct sctp_bind_hashbucket *head, struct net *net, unsigned short snum)
7339 {
7340 	struct sctp_bind_bucket *pp;
7341 
7342 	pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
7343 	if (pp) {
7344 		SCTP_DBG_OBJCNT_INC(bind_bucket);
7345 		pp->port = snum;
7346 		pp->fastreuse = 0;
7347 		INIT_HLIST_HEAD(&pp->owner);
7348 		pp->net = net;
7349 		hlist_add_head(&pp->node, &head->chain);
7350 	}
7351 	return pp;
7352 }
7353 
7354 /* Caller must hold hashbucket lock for this tb with local BH disabled */
7355 static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
7356 {
7357 	if (pp && hlist_empty(&pp->owner)) {
7358 		__hlist_del(&pp->node);
7359 		kmem_cache_free(sctp_bucket_cachep, pp);
7360 		SCTP_DBG_OBJCNT_DEC(bind_bucket);
7361 	}
7362 }
7363 
7364 /* Release this socket's reference to a local port.  */
7365 static inline void __sctp_put_port(struct sock *sk)
7366 {
7367 	struct sctp_bind_hashbucket *head =
7368 		&sctp_port_hashtable[sctp_phashfn(sock_net(sk),
7369 						  inet_sk(sk)->inet_num)];
7370 	struct sctp_bind_bucket *pp;
7371 
7372 	spin_lock(&head->lock);
7373 	pp = sctp_sk(sk)->bind_hash;
7374 	__sk_del_bind_node(sk);
7375 	sctp_sk(sk)->bind_hash = NULL;
7376 	inet_sk(sk)->inet_num = 0;
7377 	sctp_bucket_destroy(pp);
7378 	spin_unlock(&head->lock);
7379 }
7380 
7381 void sctp_put_port(struct sock *sk)
7382 {
7383 	local_bh_disable();
7384 	__sctp_put_port(sk);
7385 	local_bh_enable();
7386 }
7387 
7388 /*
7389  * The system picks an ephemeral port and choose an address set equivalent
7390  * to binding with a wildcard address.
7391  * One of those addresses will be the primary address for the association.
7392  * This automatically enables the multihoming capability of SCTP.
7393  */
7394 static int sctp_autobind(struct sock *sk)
7395 {
7396 	union sctp_addr autoaddr;
7397 	struct sctp_af *af;
7398 	__be16 port;
7399 
7400 	/* Initialize a local sockaddr structure to INADDR_ANY. */
7401 	af = sctp_sk(sk)->pf->af;
7402 
7403 	port = htons(inet_sk(sk)->inet_num);
7404 	af->inaddr_any(&autoaddr, port);
7405 
7406 	return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
7407 }
7408 
7409 /* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
7410  *
7411  * From RFC 2292
7412  * 4.2 The cmsghdr Structure *
7413  *
7414  * When ancillary data is sent or received, any number of ancillary data
7415  * objects can be specified by the msg_control and msg_controllen members of
7416  * the msghdr structure, because each object is preceded by
7417  * a cmsghdr structure defining the object's length (the cmsg_len member).
7418  * Historically Berkeley-derived implementations have passed only one object
7419  * at a time, but this API allows multiple objects to be
7420  * passed in a single call to sendmsg() or recvmsg(). The following example
7421  * shows two ancillary data objects in a control buffer.
7422  *
7423  *   |<--------------------------- msg_controllen -------------------------->|
7424  *   |                                                                       |
7425  *
7426  *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
7427  *
7428  *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
7429  *   |                                   |                                   |
7430  *
7431  *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
7432  *
7433  *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
7434  *   |                                |  |                                |  |
7435  *
7436  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
7437  *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
7438  *
7439  *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
7440  *
7441  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
7442  *    ^
7443  *    |
7444  *
7445  * msg_control
7446  * points here
7447  */
7448 static int sctp_msghdr_parse(const struct msghdr *msg, sctp_cmsgs_t *cmsgs)
7449 {
7450 	struct cmsghdr *cmsg;
7451 	struct msghdr *my_msg = (struct msghdr *)msg;
7452 
7453 	for_each_cmsghdr(cmsg, my_msg) {
7454 		if (!CMSG_OK(my_msg, cmsg))
7455 			return -EINVAL;
7456 
7457 		/* Should we parse this header or ignore?  */
7458 		if (cmsg->cmsg_level != IPPROTO_SCTP)
7459 			continue;
7460 
7461 		/* Strictly check lengths following example in SCM code.  */
7462 		switch (cmsg->cmsg_type) {
7463 		case SCTP_INIT:
7464 			/* SCTP Socket API Extension
7465 			 * 5.3.1 SCTP Initiation Structure (SCTP_INIT)
7466 			 *
7467 			 * This cmsghdr structure provides information for
7468 			 * initializing new SCTP associations with sendmsg().
7469 			 * The SCTP_INITMSG socket option uses this same data
7470 			 * structure.  This structure is not used for
7471 			 * recvmsg().
7472 			 *
7473 			 * cmsg_level    cmsg_type      cmsg_data[]
7474 			 * ------------  ------------   ----------------------
7475 			 * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
7476 			 */
7477 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_initmsg)))
7478 				return -EINVAL;
7479 
7480 			cmsgs->init = CMSG_DATA(cmsg);
7481 			break;
7482 
7483 		case SCTP_SNDRCV:
7484 			/* SCTP Socket API Extension
7485 			 * 5.3.2 SCTP Header Information Structure(SCTP_SNDRCV)
7486 			 *
7487 			 * This cmsghdr structure specifies SCTP options for
7488 			 * sendmsg() and describes SCTP header information
7489 			 * about a received message through recvmsg().
7490 			 *
7491 			 * cmsg_level    cmsg_type      cmsg_data[]
7492 			 * ------------  ------------   ----------------------
7493 			 * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
7494 			 */
7495 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
7496 				return -EINVAL;
7497 
7498 			cmsgs->srinfo = CMSG_DATA(cmsg);
7499 
7500 			if (cmsgs->srinfo->sinfo_flags &
7501 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
7502 			      SCTP_SACK_IMMEDIATELY | SCTP_PR_SCTP_MASK |
7503 			      SCTP_ABORT | SCTP_EOF))
7504 				return -EINVAL;
7505 			break;
7506 
7507 		case SCTP_SNDINFO:
7508 			/* SCTP Socket API Extension
7509 			 * 5.3.4 SCTP Send Information Structure (SCTP_SNDINFO)
7510 			 *
7511 			 * This cmsghdr structure specifies SCTP options for
7512 			 * sendmsg(). This structure and SCTP_RCVINFO replaces
7513 			 * SCTP_SNDRCV which has been deprecated.
7514 			 *
7515 			 * cmsg_level    cmsg_type      cmsg_data[]
7516 			 * ------------  ------------   ---------------------
7517 			 * IPPROTO_SCTP  SCTP_SNDINFO    struct sctp_sndinfo
7518 			 */
7519 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_sndinfo)))
7520 				return -EINVAL;
7521 
7522 			cmsgs->sinfo = CMSG_DATA(cmsg);
7523 
7524 			if (cmsgs->sinfo->snd_flags &
7525 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
7526 			      SCTP_SACK_IMMEDIATELY | SCTP_PR_SCTP_MASK |
7527 			      SCTP_ABORT | SCTP_EOF))
7528 				return -EINVAL;
7529 			break;
7530 		default:
7531 			return -EINVAL;
7532 		}
7533 	}
7534 
7535 	return 0;
7536 }
7537 
7538 /*
7539  * Wait for a packet..
7540  * Note: This function is the same function as in core/datagram.c
7541  * with a few modifications to make lksctp work.
7542  */
7543 static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p)
7544 {
7545 	int error;
7546 	DEFINE_WAIT(wait);
7547 
7548 	prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
7549 
7550 	/* Socket errors? */
7551 	error = sock_error(sk);
7552 	if (error)
7553 		goto out;
7554 
7555 	if (!skb_queue_empty(&sk->sk_receive_queue))
7556 		goto ready;
7557 
7558 	/* Socket shut down?  */
7559 	if (sk->sk_shutdown & RCV_SHUTDOWN)
7560 		goto out;
7561 
7562 	/* Sequenced packets can come disconnected.  If so we report the
7563 	 * problem.
7564 	 */
7565 	error = -ENOTCONN;
7566 
7567 	/* Is there a good reason to think that we may receive some data?  */
7568 	if (list_empty(&sctp_sk(sk)->ep->asocs) && !sctp_sstate(sk, LISTENING))
7569 		goto out;
7570 
7571 	/* Handle signals.  */
7572 	if (signal_pending(current))
7573 		goto interrupted;
7574 
7575 	/* Let another process have a go.  Since we are going to sleep
7576 	 * anyway.  Note: This may cause odd behaviors if the message
7577 	 * does not fit in the user's buffer, but this seems to be the
7578 	 * only way to honor MSG_DONTWAIT realistically.
7579 	 */
7580 	release_sock(sk);
7581 	*timeo_p = schedule_timeout(*timeo_p);
7582 	lock_sock(sk);
7583 
7584 ready:
7585 	finish_wait(sk_sleep(sk), &wait);
7586 	return 0;
7587 
7588 interrupted:
7589 	error = sock_intr_errno(*timeo_p);
7590 
7591 out:
7592 	finish_wait(sk_sleep(sk), &wait);
7593 	*err = error;
7594 	return error;
7595 }
7596 
7597 /* Receive a datagram.
7598  * Note: This is pretty much the same routine as in core/datagram.c
7599  * with a few changes to make lksctp work.
7600  */
7601 struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
7602 				       int noblock, int *err)
7603 {
7604 	int error;
7605 	struct sk_buff *skb;
7606 	long timeo;
7607 
7608 	timeo = sock_rcvtimeo(sk, noblock);
7609 
7610 	pr_debug("%s: timeo:%ld, max:%ld\n", __func__, timeo,
7611 		 MAX_SCHEDULE_TIMEOUT);
7612 
7613 	do {
7614 		/* Again only user level code calls this function,
7615 		 * so nothing interrupt level
7616 		 * will suddenly eat the receive_queue.
7617 		 *
7618 		 *  Look at current nfs client by the way...
7619 		 *  However, this function was correct in any case. 8)
7620 		 */
7621 		if (flags & MSG_PEEK) {
7622 			skb = skb_peek(&sk->sk_receive_queue);
7623 			if (skb)
7624 				refcount_inc(&skb->users);
7625 		} else {
7626 			skb = __skb_dequeue(&sk->sk_receive_queue);
7627 		}
7628 
7629 		if (skb)
7630 			return skb;
7631 
7632 		/* Caller is allowed not to check sk->sk_err before calling. */
7633 		error = sock_error(sk);
7634 		if (error)
7635 			goto no_packet;
7636 
7637 		if (sk->sk_shutdown & RCV_SHUTDOWN)
7638 			break;
7639 
7640 		if (sk_can_busy_loop(sk)) {
7641 			sk_busy_loop(sk, noblock);
7642 
7643 			if (!skb_queue_empty(&sk->sk_receive_queue))
7644 				continue;
7645 		}
7646 
7647 		/* User doesn't want to wait.  */
7648 		error = -EAGAIN;
7649 		if (!timeo)
7650 			goto no_packet;
7651 	} while (sctp_wait_for_packet(sk, err, &timeo) == 0);
7652 
7653 	return NULL;
7654 
7655 no_packet:
7656 	*err = error;
7657 	return NULL;
7658 }
7659 
7660 /* If sndbuf has changed, wake up per association sndbuf waiters.  */
7661 static void __sctp_write_space(struct sctp_association *asoc)
7662 {
7663 	struct sock *sk = asoc->base.sk;
7664 
7665 	if (sctp_wspace(asoc) <= 0)
7666 		return;
7667 
7668 	if (waitqueue_active(&asoc->wait))
7669 		wake_up_interruptible(&asoc->wait);
7670 
7671 	if (sctp_writeable(sk)) {
7672 		struct socket_wq *wq;
7673 
7674 		rcu_read_lock();
7675 		wq = rcu_dereference(sk->sk_wq);
7676 		if (wq) {
7677 			if (waitqueue_active(&wq->wait))
7678 				wake_up_interruptible(&wq->wait);
7679 
7680 			/* Note that we try to include the Async I/O support
7681 			 * here by modeling from the current TCP/UDP code.
7682 			 * We have not tested with it yet.
7683 			 */
7684 			if (!(sk->sk_shutdown & SEND_SHUTDOWN))
7685 				sock_wake_async(wq, SOCK_WAKE_SPACE, POLL_OUT);
7686 		}
7687 		rcu_read_unlock();
7688 	}
7689 }
7690 
7691 static void sctp_wake_up_waiters(struct sock *sk,
7692 				 struct sctp_association *asoc)
7693 {
7694 	struct sctp_association *tmp = asoc;
7695 
7696 	/* We do accounting for the sndbuf space per association,
7697 	 * so we only need to wake our own association.
7698 	 */
7699 	if (asoc->ep->sndbuf_policy)
7700 		return __sctp_write_space(asoc);
7701 
7702 	/* If association goes down and is just flushing its
7703 	 * outq, then just normally notify others.
7704 	 */
7705 	if (asoc->base.dead)
7706 		return sctp_write_space(sk);
7707 
7708 	/* Accounting for the sndbuf space is per socket, so we
7709 	 * need to wake up others, try to be fair and in case of
7710 	 * other associations, let them have a go first instead
7711 	 * of just doing a sctp_write_space() call.
7712 	 *
7713 	 * Note that we reach sctp_wake_up_waiters() only when
7714 	 * associations free up queued chunks, thus we are under
7715 	 * lock and the list of associations on a socket is
7716 	 * guaranteed not to change.
7717 	 */
7718 	for (tmp = list_next_entry(tmp, asocs); 1;
7719 	     tmp = list_next_entry(tmp, asocs)) {
7720 		/* Manually skip the head element. */
7721 		if (&tmp->asocs == &((sctp_sk(sk))->ep->asocs))
7722 			continue;
7723 		/* Wake up association. */
7724 		__sctp_write_space(tmp);
7725 		/* We've reached the end. */
7726 		if (tmp == asoc)
7727 			break;
7728 	}
7729 }
7730 
7731 /* Do accounting for the sndbuf space.
7732  * Decrement the used sndbuf space of the corresponding association by the
7733  * data size which was just transmitted(freed).
7734  */
7735 static void sctp_wfree(struct sk_buff *skb)
7736 {
7737 	struct sctp_chunk *chunk = skb_shinfo(skb)->destructor_arg;
7738 	struct sctp_association *asoc = chunk->asoc;
7739 	struct sock *sk = asoc->base.sk;
7740 
7741 	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
7742 				sizeof(struct sk_buff) +
7743 				sizeof(struct sctp_chunk);
7744 
7745 	WARN_ON(refcount_sub_and_test(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc));
7746 
7747 	/*
7748 	 * This undoes what is done via sctp_set_owner_w and sk_mem_charge
7749 	 */
7750 	sk->sk_wmem_queued   -= skb->truesize;
7751 	sk_mem_uncharge(sk, skb->truesize);
7752 
7753 	sock_wfree(skb);
7754 	sctp_wake_up_waiters(sk, asoc);
7755 
7756 	sctp_association_put(asoc);
7757 }
7758 
7759 /* Do accounting for the receive space on the socket.
7760  * Accounting for the association is done in ulpevent.c
7761  * We set this as a destructor for the cloned data skbs so that
7762  * accounting is done at the correct time.
7763  */
7764 void sctp_sock_rfree(struct sk_buff *skb)
7765 {
7766 	struct sock *sk = skb->sk;
7767 	struct sctp_ulpevent *event = sctp_skb2event(skb);
7768 
7769 	atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
7770 
7771 	/*
7772 	 * Mimic the behavior of sock_rfree
7773 	 */
7774 	sk_mem_uncharge(sk, event->rmem_len);
7775 }
7776 
7777 
7778 /* Helper function to wait for space in the sndbuf.  */
7779 static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
7780 				size_t msg_len)
7781 {
7782 	struct sock *sk = asoc->base.sk;
7783 	int err = 0;
7784 	long current_timeo = *timeo_p;
7785 	DEFINE_WAIT(wait);
7786 
7787 	pr_debug("%s: asoc:%p, timeo:%ld, msg_len:%zu\n", __func__, asoc,
7788 		 *timeo_p, msg_len);
7789 
7790 	/* Increment the association's refcnt.  */
7791 	sctp_association_hold(asoc);
7792 
7793 	/* Wait on the association specific sndbuf space. */
7794 	for (;;) {
7795 		prepare_to_wait_exclusive(&asoc->wait, &wait,
7796 					  TASK_INTERRUPTIBLE);
7797 		if (!*timeo_p)
7798 			goto do_nonblock;
7799 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
7800 		    asoc->base.dead)
7801 			goto do_error;
7802 		if (signal_pending(current))
7803 			goto do_interrupted;
7804 		if (msg_len <= sctp_wspace(asoc))
7805 			break;
7806 
7807 		/* Let another process have a go.  Since we are going
7808 		 * to sleep anyway.
7809 		 */
7810 		release_sock(sk);
7811 		current_timeo = schedule_timeout(current_timeo);
7812 		lock_sock(sk);
7813 
7814 		*timeo_p = current_timeo;
7815 	}
7816 
7817 out:
7818 	finish_wait(&asoc->wait, &wait);
7819 
7820 	/* Release the association's refcnt.  */
7821 	sctp_association_put(asoc);
7822 
7823 	return err;
7824 
7825 do_error:
7826 	err = -EPIPE;
7827 	goto out;
7828 
7829 do_interrupted:
7830 	err = sock_intr_errno(*timeo_p);
7831 	goto out;
7832 
7833 do_nonblock:
7834 	err = -EAGAIN;
7835 	goto out;
7836 }
7837 
7838 void sctp_data_ready(struct sock *sk)
7839 {
7840 	struct socket_wq *wq;
7841 
7842 	rcu_read_lock();
7843 	wq = rcu_dereference(sk->sk_wq);
7844 	if (skwq_has_sleeper(wq))
7845 		wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
7846 						POLLRDNORM | POLLRDBAND);
7847 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
7848 	rcu_read_unlock();
7849 }
7850 
7851 /* If socket sndbuf has changed, wake up all per association waiters.  */
7852 void sctp_write_space(struct sock *sk)
7853 {
7854 	struct sctp_association *asoc;
7855 
7856 	/* Wake up the tasks in each wait queue.  */
7857 	list_for_each_entry(asoc, &((sctp_sk(sk))->ep->asocs), asocs) {
7858 		__sctp_write_space(asoc);
7859 	}
7860 }
7861 
7862 /* Is there any sndbuf space available on the socket?
7863  *
7864  * Note that sk_wmem_alloc is the sum of the send buffers on all of the
7865  * associations on the same socket.  For a UDP-style socket with
7866  * multiple associations, it is possible for it to be "unwriteable"
7867  * prematurely.  I assume that this is acceptable because
7868  * a premature "unwriteable" is better than an accidental "writeable" which
7869  * would cause an unwanted block under certain circumstances.  For the 1-1
7870  * UDP-style sockets or TCP-style sockets, this code should work.
7871  *  - Daisy
7872  */
7873 static int sctp_writeable(struct sock *sk)
7874 {
7875 	int amt = 0;
7876 
7877 	amt = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
7878 	if (amt < 0)
7879 		amt = 0;
7880 	return amt;
7881 }
7882 
7883 /* Wait for an association to go into ESTABLISHED state. If timeout is 0,
7884  * returns immediately with EINPROGRESS.
7885  */
7886 static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
7887 {
7888 	struct sock *sk = asoc->base.sk;
7889 	int err = 0;
7890 	long current_timeo = *timeo_p;
7891 	DEFINE_WAIT(wait);
7892 
7893 	pr_debug("%s: asoc:%p, timeo:%ld\n", __func__, asoc, *timeo_p);
7894 
7895 	/* Increment the association's refcnt.  */
7896 	sctp_association_hold(asoc);
7897 
7898 	for (;;) {
7899 		prepare_to_wait_exclusive(&asoc->wait, &wait,
7900 					  TASK_INTERRUPTIBLE);
7901 		if (!*timeo_p)
7902 			goto do_nonblock;
7903 		if (sk->sk_shutdown & RCV_SHUTDOWN)
7904 			break;
7905 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
7906 		    asoc->base.dead)
7907 			goto do_error;
7908 		if (signal_pending(current))
7909 			goto do_interrupted;
7910 
7911 		if (sctp_state(asoc, ESTABLISHED))
7912 			break;
7913 
7914 		/* Let another process have a go.  Since we are going
7915 		 * to sleep anyway.
7916 		 */
7917 		release_sock(sk);
7918 		current_timeo = schedule_timeout(current_timeo);
7919 		lock_sock(sk);
7920 
7921 		*timeo_p = current_timeo;
7922 	}
7923 
7924 out:
7925 	finish_wait(&asoc->wait, &wait);
7926 
7927 	/* Release the association's refcnt.  */
7928 	sctp_association_put(asoc);
7929 
7930 	return err;
7931 
7932 do_error:
7933 	if (asoc->init_err_counter + 1 > asoc->max_init_attempts)
7934 		err = -ETIMEDOUT;
7935 	else
7936 		err = -ECONNREFUSED;
7937 	goto out;
7938 
7939 do_interrupted:
7940 	err = sock_intr_errno(*timeo_p);
7941 	goto out;
7942 
7943 do_nonblock:
7944 	err = -EINPROGRESS;
7945 	goto out;
7946 }
7947 
7948 static int sctp_wait_for_accept(struct sock *sk, long timeo)
7949 {
7950 	struct sctp_endpoint *ep;
7951 	int err = 0;
7952 	DEFINE_WAIT(wait);
7953 
7954 	ep = sctp_sk(sk)->ep;
7955 
7956 
7957 	for (;;) {
7958 		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
7959 					  TASK_INTERRUPTIBLE);
7960 
7961 		if (list_empty(&ep->asocs)) {
7962 			release_sock(sk);
7963 			timeo = schedule_timeout(timeo);
7964 			lock_sock(sk);
7965 		}
7966 
7967 		err = -EINVAL;
7968 		if (!sctp_sstate(sk, LISTENING))
7969 			break;
7970 
7971 		err = 0;
7972 		if (!list_empty(&ep->asocs))
7973 			break;
7974 
7975 		err = sock_intr_errno(timeo);
7976 		if (signal_pending(current))
7977 			break;
7978 
7979 		err = -EAGAIN;
7980 		if (!timeo)
7981 			break;
7982 	}
7983 
7984 	finish_wait(sk_sleep(sk), &wait);
7985 
7986 	return err;
7987 }
7988 
7989 static void sctp_wait_for_close(struct sock *sk, long timeout)
7990 {
7991 	DEFINE_WAIT(wait);
7992 
7993 	do {
7994 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
7995 		if (list_empty(&sctp_sk(sk)->ep->asocs))
7996 			break;
7997 		release_sock(sk);
7998 		timeout = schedule_timeout(timeout);
7999 		lock_sock(sk);
8000 	} while (!signal_pending(current) && timeout);
8001 
8002 	finish_wait(sk_sleep(sk), &wait);
8003 }
8004 
8005 static void sctp_skb_set_owner_r_frag(struct sk_buff *skb, struct sock *sk)
8006 {
8007 	struct sk_buff *frag;
8008 
8009 	if (!skb->data_len)
8010 		goto done;
8011 
8012 	/* Don't forget the fragments. */
8013 	skb_walk_frags(skb, frag)
8014 		sctp_skb_set_owner_r_frag(frag, sk);
8015 
8016 done:
8017 	sctp_skb_set_owner_r(skb, sk);
8018 }
8019 
8020 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
8021 		    struct sctp_association *asoc)
8022 {
8023 	struct inet_sock *inet = inet_sk(sk);
8024 	struct inet_sock *newinet;
8025 
8026 	newsk->sk_type = sk->sk_type;
8027 	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
8028 	newsk->sk_flags = sk->sk_flags;
8029 	newsk->sk_tsflags = sk->sk_tsflags;
8030 	newsk->sk_no_check_tx = sk->sk_no_check_tx;
8031 	newsk->sk_no_check_rx = sk->sk_no_check_rx;
8032 	newsk->sk_reuse = sk->sk_reuse;
8033 
8034 	newsk->sk_shutdown = sk->sk_shutdown;
8035 	newsk->sk_destruct = sctp_destruct_sock;
8036 	newsk->sk_family = sk->sk_family;
8037 	newsk->sk_protocol = IPPROTO_SCTP;
8038 	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
8039 	newsk->sk_sndbuf = sk->sk_sndbuf;
8040 	newsk->sk_rcvbuf = sk->sk_rcvbuf;
8041 	newsk->sk_lingertime = sk->sk_lingertime;
8042 	newsk->sk_rcvtimeo = sk->sk_rcvtimeo;
8043 	newsk->sk_sndtimeo = sk->sk_sndtimeo;
8044 	newsk->sk_rxhash = sk->sk_rxhash;
8045 
8046 	newinet = inet_sk(newsk);
8047 
8048 	/* Initialize sk's sport, dport, rcv_saddr and daddr for
8049 	 * getsockname() and getpeername()
8050 	 */
8051 	newinet->inet_sport = inet->inet_sport;
8052 	newinet->inet_saddr = inet->inet_saddr;
8053 	newinet->inet_rcv_saddr = inet->inet_rcv_saddr;
8054 	newinet->inet_dport = htons(asoc->peer.port);
8055 	newinet->pmtudisc = inet->pmtudisc;
8056 	newinet->inet_id = asoc->next_tsn ^ jiffies;
8057 
8058 	newinet->uc_ttl = inet->uc_ttl;
8059 	newinet->mc_loop = 1;
8060 	newinet->mc_ttl = 1;
8061 	newinet->mc_index = 0;
8062 	newinet->mc_list = NULL;
8063 
8064 	if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
8065 		net_enable_timestamp();
8066 
8067 	security_sk_clone(sk, newsk);
8068 }
8069 
8070 static inline void sctp_copy_descendant(struct sock *sk_to,
8071 					const struct sock *sk_from)
8072 {
8073 	int ancestor_size = sizeof(struct inet_sock) +
8074 			    sizeof(struct sctp_sock) -
8075 			    offsetof(struct sctp_sock, auto_asconf_list);
8076 
8077 	if (sk_from->sk_family == PF_INET6)
8078 		ancestor_size += sizeof(struct ipv6_pinfo);
8079 
8080 	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
8081 }
8082 
8083 /* Populate the fields of the newsk from the oldsk and migrate the assoc
8084  * and its messages to the newsk.
8085  */
8086 static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
8087 			      struct sctp_association *assoc,
8088 			      sctp_socket_type_t type)
8089 {
8090 	struct sctp_sock *oldsp = sctp_sk(oldsk);
8091 	struct sctp_sock *newsp = sctp_sk(newsk);
8092 	struct sctp_bind_bucket *pp; /* hash list port iterator */
8093 	struct sctp_endpoint *newep = newsp->ep;
8094 	struct sk_buff *skb, *tmp;
8095 	struct sctp_ulpevent *event;
8096 	struct sctp_bind_hashbucket *head;
8097 
8098 	/* Migrate socket buffer sizes and all the socket level options to the
8099 	 * new socket.
8100 	 */
8101 	newsk->sk_sndbuf = oldsk->sk_sndbuf;
8102 	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
8103 	/* Brute force copy old sctp opt. */
8104 	sctp_copy_descendant(newsk, oldsk);
8105 
8106 	/* Restore the ep value that was overwritten with the above structure
8107 	 * copy.
8108 	 */
8109 	newsp->ep = newep;
8110 	newsp->hmac = NULL;
8111 
8112 	/* Hook this new socket in to the bind_hash list. */
8113 	head = &sctp_port_hashtable[sctp_phashfn(sock_net(oldsk),
8114 						 inet_sk(oldsk)->inet_num)];
8115 	spin_lock_bh(&head->lock);
8116 	pp = sctp_sk(oldsk)->bind_hash;
8117 	sk_add_bind_node(newsk, &pp->owner);
8118 	sctp_sk(newsk)->bind_hash = pp;
8119 	inet_sk(newsk)->inet_num = inet_sk(oldsk)->inet_num;
8120 	spin_unlock_bh(&head->lock);
8121 
8122 	/* Copy the bind_addr list from the original endpoint to the new
8123 	 * endpoint so that we can handle restarts properly
8124 	 */
8125 	sctp_bind_addr_dup(&newsp->ep->base.bind_addr,
8126 				&oldsp->ep->base.bind_addr, GFP_KERNEL);
8127 
8128 	/* Move any messages in the old socket's receive queue that are for the
8129 	 * peeled off association to the new socket's receive queue.
8130 	 */
8131 	sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
8132 		event = sctp_skb2event(skb);
8133 		if (event->asoc == assoc) {
8134 			__skb_unlink(skb, &oldsk->sk_receive_queue);
8135 			__skb_queue_tail(&newsk->sk_receive_queue, skb);
8136 			sctp_skb_set_owner_r_frag(skb, newsk);
8137 		}
8138 	}
8139 
8140 	/* Clean up any messages pending delivery due to partial
8141 	 * delivery.   Three cases:
8142 	 * 1) No partial deliver;  no work.
8143 	 * 2) Peeling off partial delivery; keep pd_lobby in new pd_lobby.
8144 	 * 3) Peeling off non-partial delivery; move pd_lobby to receive_queue.
8145 	 */
8146 	skb_queue_head_init(&newsp->pd_lobby);
8147 	atomic_set(&sctp_sk(newsk)->pd_mode, assoc->ulpq.pd_mode);
8148 
8149 	if (atomic_read(&sctp_sk(oldsk)->pd_mode)) {
8150 		struct sk_buff_head *queue;
8151 
8152 		/* Decide which queue to move pd_lobby skbs to. */
8153 		if (assoc->ulpq.pd_mode) {
8154 			queue = &newsp->pd_lobby;
8155 		} else
8156 			queue = &newsk->sk_receive_queue;
8157 
8158 		/* Walk through the pd_lobby, looking for skbs that
8159 		 * need moved to the new socket.
8160 		 */
8161 		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
8162 			event = sctp_skb2event(skb);
8163 			if (event->asoc == assoc) {
8164 				__skb_unlink(skb, &oldsp->pd_lobby);
8165 				__skb_queue_tail(queue, skb);
8166 				sctp_skb_set_owner_r_frag(skb, newsk);
8167 			}
8168 		}
8169 
8170 		/* Clear up any skbs waiting for the partial
8171 		 * delivery to finish.
8172 		 */
8173 		if (assoc->ulpq.pd_mode)
8174 			sctp_clear_pd(oldsk, NULL);
8175 
8176 	}
8177 
8178 	sctp_skb_for_each(skb, &assoc->ulpq.reasm, tmp)
8179 		sctp_skb_set_owner_r_frag(skb, newsk);
8180 
8181 	sctp_skb_for_each(skb, &assoc->ulpq.lobby, tmp)
8182 		sctp_skb_set_owner_r_frag(skb, newsk);
8183 
8184 	/* Set the type of socket to indicate that it is peeled off from the
8185 	 * original UDP-style socket or created with the accept() call on a
8186 	 * TCP-style socket..
8187 	 */
8188 	newsp->type = type;
8189 
8190 	/* Mark the new socket "in-use" by the user so that any packets
8191 	 * that may arrive on the association after we've moved it are
8192 	 * queued to the backlog.  This prevents a potential race between
8193 	 * backlog processing on the old socket and new-packet processing
8194 	 * on the new socket.
8195 	 *
8196 	 * The caller has just allocated newsk so we can guarantee that other
8197 	 * paths won't try to lock it and then oldsk.
8198 	 */
8199 	lock_sock_nested(newsk, SINGLE_DEPTH_NESTING);
8200 	sctp_assoc_migrate(assoc, newsk);
8201 
8202 	/* If the association on the newsk is already closed before accept()
8203 	 * is called, set RCV_SHUTDOWN flag.
8204 	 */
8205 	if (sctp_state(assoc, CLOSED) && sctp_style(newsk, TCP)) {
8206 		newsk->sk_state = SCTP_SS_CLOSED;
8207 		newsk->sk_shutdown |= RCV_SHUTDOWN;
8208 	} else {
8209 		newsk->sk_state = SCTP_SS_ESTABLISHED;
8210 	}
8211 
8212 	release_sock(newsk);
8213 }
8214 
8215 
8216 /* This proto struct describes the ULP interface for SCTP.  */
8217 struct proto sctp_prot = {
8218 	.name        =	"SCTP",
8219 	.owner       =	THIS_MODULE,
8220 	.close       =	sctp_close,
8221 	.connect     =	sctp_connect,
8222 	.disconnect  =	sctp_disconnect,
8223 	.accept      =	sctp_accept,
8224 	.ioctl       =	sctp_ioctl,
8225 	.init        =	sctp_init_sock,
8226 	.destroy     =	sctp_destroy_sock,
8227 	.shutdown    =	sctp_shutdown,
8228 	.setsockopt  =	sctp_setsockopt,
8229 	.getsockopt  =	sctp_getsockopt,
8230 	.sendmsg     =	sctp_sendmsg,
8231 	.recvmsg     =	sctp_recvmsg,
8232 	.bind        =	sctp_bind,
8233 	.backlog_rcv =	sctp_backlog_rcv,
8234 	.hash        =	sctp_hash,
8235 	.unhash      =	sctp_unhash,
8236 	.get_port    =	sctp_get_port,
8237 	.obj_size    =  sizeof(struct sctp_sock),
8238 	.sysctl_mem  =  sysctl_sctp_mem,
8239 	.sysctl_rmem =  sysctl_sctp_rmem,
8240 	.sysctl_wmem =  sysctl_sctp_wmem,
8241 	.memory_pressure = &sctp_memory_pressure,
8242 	.enter_memory_pressure = sctp_enter_memory_pressure,
8243 	.memory_allocated = &sctp_memory_allocated,
8244 	.sockets_allocated = &sctp_sockets_allocated,
8245 };
8246 
8247 #if IS_ENABLED(CONFIG_IPV6)
8248 
8249 #include <net/transp_v6.h>
8250 static void sctp_v6_destroy_sock(struct sock *sk)
8251 {
8252 	sctp_destroy_sock(sk);
8253 	inet6_destroy_sock(sk);
8254 }
8255 
8256 struct proto sctpv6_prot = {
8257 	.name		= "SCTPv6",
8258 	.owner		= THIS_MODULE,
8259 	.close		= sctp_close,
8260 	.connect	= sctp_connect,
8261 	.disconnect	= sctp_disconnect,
8262 	.accept		= sctp_accept,
8263 	.ioctl		= sctp_ioctl,
8264 	.init		= sctp_init_sock,
8265 	.destroy	= sctp_v6_destroy_sock,
8266 	.shutdown	= sctp_shutdown,
8267 	.setsockopt	= sctp_setsockopt,
8268 	.getsockopt	= sctp_getsockopt,
8269 	.sendmsg	= sctp_sendmsg,
8270 	.recvmsg	= sctp_recvmsg,
8271 	.bind		= sctp_bind,
8272 	.backlog_rcv	= sctp_backlog_rcv,
8273 	.hash		= sctp_hash,
8274 	.unhash		= sctp_unhash,
8275 	.get_port	= sctp_get_port,
8276 	.obj_size	= sizeof(struct sctp6_sock),
8277 	.sysctl_mem	= sysctl_sctp_mem,
8278 	.sysctl_rmem	= sysctl_sctp_rmem,
8279 	.sysctl_wmem	= sysctl_sctp_wmem,
8280 	.memory_pressure = &sctp_memory_pressure,
8281 	.enter_memory_pressure = sctp_enter_memory_pressure,
8282 	.memory_allocated = &sctp_memory_allocated,
8283 	.sockets_allocated = &sctp_sockets_allocated,
8284 };
8285 #endif /* IS_ENABLED(CONFIG_IPV6) */
8286