xref: /openbmc/linux/net/sctp/socket.c (revision ae3473231e77a3f1909d48cd144cebe5e1d049b3)
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/ip.h>
61 #include <linux/capability.h>
62 #include <linux/fcntl.h>
63 #include <linux/poll.h>
64 #include <linux/init.h>
65 #include <linux/slab.h>
66 #include <linux/file.h>
67 #include <linux/compat.h>
68 
69 #include <net/ip.h>
70 #include <net/icmp.h>
71 #include <net/route.h>
72 #include <net/ipv6.h>
73 #include <net/inet_common.h>
74 #include <net/busy_poll.h>
75 
76 #include <linux/socket.h> /* for sa_family_t */
77 #include <linux/export.h>
78 #include <net/sock.h>
79 #include <net/sctp/sctp.h>
80 #include <net/sctp/sm.h>
81 
82 /* Forward declarations for internal helper functions. */
83 static int sctp_writeable(struct sock *sk);
84 static void sctp_wfree(struct sk_buff *skb);
85 static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p,
86 				size_t msg_len);
87 static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p);
88 static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);
89 static int sctp_wait_for_accept(struct sock *sk, long timeo);
90 static void sctp_wait_for_close(struct sock *sk, long timeo);
91 static void sctp_destruct_sock(struct sock *sk);
92 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
93 					union sctp_addr *addr, int len);
94 static int sctp_bindx_add(struct sock *, struct sockaddr *, int);
95 static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);
96 static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);
97 static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);
98 static int sctp_send_asconf(struct sctp_association *asoc,
99 			    struct sctp_chunk *chunk);
100 static int sctp_do_bind(struct sock *, union sctp_addr *, int);
101 static int sctp_autobind(struct sock *sk);
102 static void sctp_sock_migrate(struct sock *, struct sock *,
103 			      struct sctp_association *, sctp_socket_type_t);
104 
105 static int sctp_memory_pressure;
106 static atomic_long_t sctp_memory_allocated;
107 struct percpu_counter sctp_sockets_allocated;
108 
109 static void sctp_enter_memory_pressure(struct sock *sk)
110 {
111 	sctp_memory_pressure = 1;
112 }
113 
114 
115 /* Get the sndbuf space available at the time on the association.  */
116 static inline int sctp_wspace(struct sctp_association *asoc)
117 {
118 	int amt;
119 
120 	if (asoc->ep->sndbuf_policy)
121 		amt = asoc->sndbuf_used;
122 	else
123 		amt = sk_wmem_alloc_get(asoc->base.sk);
124 
125 	if (amt >= asoc->base.sk->sk_sndbuf) {
126 		if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK)
127 			amt = 0;
128 		else {
129 			amt = sk_stream_wspace(asoc->base.sk);
130 			if (amt < 0)
131 				amt = 0;
132 		}
133 	} else {
134 		amt = asoc->base.sk->sk_sndbuf - amt;
135 	}
136 	return amt;
137 }
138 
139 /* Increment the used sndbuf space count of the corresponding association by
140  * the size of the outgoing data chunk.
141  * Also, set the skb destructor for sndbuf accounting later.
142  *
143  * Since it is always 1-1 between chunk and skb, and also a new skb is always
144  * allocated for chunk bundling in sctp_packet_transmit(), we can use the
145  * destructor in the data chunk skb for the purpose of the sndbuf space
146  * tracking.
147  */
148 static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
149 {
150 	struct sctp_association *asoc = chunk->asoc;
151 	struct sock *sk = asoc->base.sk;
152 
153 	/* The sndbuf space is tracked per association.  */
154 	sctp_association_hold(asoc);
155 
156 	skb_set_owner_w(chunk->skb, sk);
157 
158 	chunk->skb->destructor = sctp_wfree;
159 	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
160 	skb_shinfo(chunk->skb)->destructor_arg = chunk;
161 
162 	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
163 				sizeof(struct sk_buff) +
164 				sizeof(struct sctp_chunk);
165 
166 	atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
167 	sk->sk_wmem_queued += chunk->skb->truesize;
168 	sk_mem_charge(sk, chunk->skb->truesize);
169 }
170 
171 /* Verify that this is a valid address. */
172 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
173 				   int len)
174 {
175 	struct sctp_af *af;
176 
177 	/* Verify basic sockaddr. */
178 	af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
179 	if (!af)
180 		return -EINVAL;
181 
182 	/* Is this a valid SCTP address?  */
183 	if (!af->addr_valid(addr, sctp_sk(sk), NULL))
184 		return -EINVAL;
185 
186 	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
187 		return -EINVAL;
188 
189 	return 0;
190 }
191 
192 /* Look up the association by its id.  If this is not a UDP-style
193  * socket, the ID field is always ignored.
194  */
195 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
196 {
197 	struct sctp_association *asoc = NULL;
198 
199 	/* If this is not a UDP-style socket, assoc id should be ignored. */
200 	if (!sctp_style(sk, UDP)) {
201 		/* Return NULL if the socket state is not ESTABLISHED. It
202 		 * could be a TCP-style listening socket or a socket which
203 		 * hasn't yet called connect() to establish an association.
204 		 */
205 		if (!sctp_sstate(sk, ESTABLISHED) && !sctp_sstate(sk, CLOSING))
206 			return NULL;
207 
208 		/* Get the first and the only association from the list. */
209 		if (!list_empty(&sctp_sk(sk)->ep->asocs))
210 			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
211 					  struct sctp_association, asocs);
212 		return asoc;
213 	}
214 
215 	/* Otherwise this is a UDP-style socket. */
216 	if (!id || (id == (sctp_assoc_t)-1))
217 		return NULL;
218 
219 	spin_lock_bh(&sctp_assocs_id_lock);
220 	asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
221 	spin_unlock_bh(&sctp_assocs_id_lock);
222 
223 	if (!asoc || (asoc->base.sk != sk) || asoc->base.dead)
224 		return NULL;
225 
226 	return asoc;
227 }
228 
229 /* Look up the transport from an address and an assoc id. If both address and
230  * id are specified, the associations matching the address and the id should be
231  * the same.
232  */
233 static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
234 					      struct sockaddr_storage *addr,
235 					      sctp_assoc_t id)
236 {
237 	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
238 	struct sctp_transport *transport;
239 	union sctp_addr *laddr = (union sctp_addr *)addr;
240 
241 	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
242 					       laddr,
243 					       &transport);
244 
245 	if (!addr_asoc)
246 		return NULL;
247 
248 	id_asoc = sctp_id2assoc(sk, id);
249 	if (id_asoc && (id_asoc != addr_asoc))
250 		return NULL;
251 
252 	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sctp_sk(sk),
253 						(union sctp_addr *)addr);
254 
255 	return transport;
256 }
257 
258 /* API 3.1.2 bind() - UDP Style Syntax
259  * The syntax of bind() is,
260  *
261  *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
262  *
263  *   sd      - the socket descriptor returned by socket().
264  *   addr    - the address structure (struct sockaddr_in or struct
265  *             sockaddr_in6 [RFC 2553]),
266  *   addr_len - the size of the address structure.
267  */
268 static int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
269 {
270 	int retval = 0;
271 
272 	lock_sock(sk);
273 
274 	pr_debug("%s: sk:%p, addr:%p, addr_len:%d\n", __func__, sk,
275 		 addr, addr_len);
276 
277 	/* Disallow binding twice. */
278 	if (!sctp_sk(sk)->ep->base.bind_addr.port)
279 		retval = sctp_do_bind(sk, (union sctp_addr *)addr,
280 				      addr_len);
281 	else
282 		retval = -EINVAL;
283 
284 	release_sock(sk);
285 
286 	return retval;
287 }
288 
289 static long sctp_get_port_local(struct sock *, union sctp_addr *);
290 
291 /* Verify this is a valid sockaddr. */
292 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
293 					union sctp_addr *addr, int len)
294 {
295 	struct sctp_af *af;
296 
297 	/* Check minimum size.  */
298 	if (len < sizeof (struct sockaddr))
299 		return NULL;
300 
301 	/* V4 mapped address are really of AF_INET family */
302 	if (addr->sa.sa_family == AF_INET6 &&
303 	    ipv6_addr_v4mapped(&addr->v6.sin6_addr)) {
304 		if (!opt->pf->af_supported(AF_INET, opt))
305 			return NULL;
306 	} else {
307 		/* Does this PF support this AF? */
308 		if (!opt->pf->af_supported(addr->sa.sa_family, opt))
309 			return NULL;
310 	}
311 
312 	/* If we get this far, af is valid. */
313 	af = sctp_get_af_specific(addr->sa.sa_family);
314 
315 	if (len < af->sockaddr_len)
316 		return NULL;
317 
318 	return af;
319 }
320 
321 /* Bind a local address either to an endpoint or to an association.  */
322 static int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
323 {
324 	struct net *net = sock_net(sk);
325 	struct sctp_sock *sp = sctp_sk(sk);
326 	struct sctp_endpoint *ep = sp->ep;
327 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
328 	struct sctp_af *af;
329 	unsigned short snum;
330 	int ret = 0;
331 
332 	/* Common sockaddr verification. */
333 	af = sctp_sockaddr_af(sp, addr, len);
334 	if (!af) {
335 		pr_debug("%s: sk:%p, newaddr:%p, len:%d EINVAL\n",
336 			 __func__, sk, addr, len);
337 		return -EINVAL;
338 	}
339 
340 	snum = ntohs(addr->v4.sin_port);
341 
342 	pr_debug("%s: sk:%p, new addr:%pISc, port:%d, new port:%d, len:%d\n",
343 		 __func__, sk, &addr->sa, bp->port, snum, len);
344 
345 	/* PF specific bind() address verification. */
346 	if (!sp->pf->bind_verify(sp, addr))
347 		return -EADDRNOTAVAIL;
348 
349 	/* We must either be unbound, or bind to the same port.
350 	 * It's OK to allow 0 ports if we are already bound.
351 	 * We'll just inhert an already bound port in this case
352 	 */
353 	if (bp->port) {
354 		if (!snum)
355 			snum = bp->port;
356 		else if (snum != bp->port) {
357 			pr_debug("%s: new port %d doesn't match existing port "
358 				 "%d\n", __func__, snum, bp->port);
359 			return -EINVAL;
360 		}
361 	}
362 
363 	if (snum && snum < PROT_SOCK &&
364 	    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
365 		return -EACCES;
366 
367 	/* See if the address matches any of the addresses we may have
368 	 * already bound before checking against other endpoints.
369 	 */
370 	if (sctp_bind_addr_match(bp, addr, sp))
371 		return -EINVAL;
372 
373 	/* Make sure we are allowed to bind here.
374 	 * The function sctp_get_port_local() does duplicate address
375 	 * detection.
376 	 */
377 	addr->v4.sin_port = htons(snum);
378 	if ((ret = sctp_get_port_local(sk, addr))) {
379 		return -EADDRINUSE;
380 	}
381 
382 	/* Refresh ephemeral port.  */
383 	if (!bp->port)
384 		bp->port = inet_sk(sk)->inet_num;
385 
386 	/* Add the address to the bind address list.
387 	 * Use GFP_ATOMIC since BHs will be disabled.
388 	 */
389 	ret = sctp_add_bind_addr(bp, addr, af->sockaddr_len,
390 				 SCTP_ADDR_SRC, GFP_ATOMIC);
391 
392 	/* Copy back into socket for getsockname() use. */
393 	if (!ret) {
394 		inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num);
395 		sp->pf->to_sk_saddr(addr, sk);
396 	}
397 
398 	return ret;
399 }
400 
401  /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
402  *
403  * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
404  * at any one time.  If a sender, after sending an ASCONF chunk, decides
405  * it needs to transfer another ASCONF Chunk, it MUST wait until the
406  * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
407  * subsequent ASCONF. Note this restriction binds each side, so at any
408  * time two ASCONF may be in-transit on any given association (one sent
409  * from each endpoint).
410  */
411 static int sctp_send_asconf(struct sctp_association *asoc,
412 			    struct sctp_chunk *chunk)
413 {
414 	struct net 	*net = sock_net(asoc->base.sk);
415 	int		retval = 0;
416 
417 	/* If there is an outstanding ASCONF chunk, queue it for later
418 	 * transmission.
419 	 */
420 	if (asoc->addip_last_asconf) {
421 		list_add_tail(&chunk->list, &asoc->addip_chunk_list);
422 		goto out;
423 	}
424 
425 	/* Hold the chunk until an ASCONF_ACK is received. */
426 	sctp_chunk_hold(chunk);
427 	retval = sctp_primitive_ASCONF(net, asoc, chunk);
428 	if (retval)
429 		sctp_chunk_free(chunk);
430 	else
431 		asoc->addip_last_asconf = chunk;
432 
433 out:
434 	return retval;
435 }
436 
437 /* Add a list of addresses as bind addresses to local endpoint or
438  * association.
439  *
440  * Basically run through each address specified in the addrs/addrcnt
441  * array/length pair, determine if it is IPv6 or IPv4 and call
442  * sctp_do_bind() on it.
443  *
444  * If any of them fails, then the operation will be reversed and the
445  * ones that were added will be removed.
446  *
447  * Only sctp_setsockopt_bindx() is supposed to call this function.
448  */
449 static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
450 {
451 	int cnt;
452 	int retval = 0;
453 	void *addr_buf;
454 	struct sockaddr *sa_addr;
455 	struct sctp_af *af;
456 
457 	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n", __func__, sk,
458 		 addrs, addrcnt);
459 
460 	addr_buf = addrs;
461 	for (cnt = 0; cnt < addrcnt; cnt++) {
462 		/* The list may contain either IPv4 or IPv6 address;
463 		 * determine the address length for walking thru the list.
464 		 */
465 		sa_addr = addr_buf;
466 		af = sctp_get_af_specific(sa_addr->sa_family);
467 		if (!af) {
468 			retval = -EINVAL;
469 			goto err_bindx_add;
470 		}
471 
472 		retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
473 				      af->sockaddr_len);
474 
475 		addr_buf += af->sockaddr_len;
476 
477 err_bindx_add:
478 		if (retval < 0) {
479 			/* Failed. Cleanup the ones that have been added */
480 			if (cnt > 0)
481 				sctp_bindx_rem(sk, addrs, cnt);
482 			return retval;
483 		}
484 	}
485 
486 	return retval;
487 }
488 
489 /* Send an ASCONF chunk with Add IP address parameters to all the peers of the
490  * associations that are part of the endpoint indicating that a list of local
491  * addresses are added to the endpoint.
492  *
493  * If any of the addresses is already in the bind address list of the
494  * association, we do not send the chunk for that association.  But it will not
495  * affect other associations.
496  *
497  * Only sctp_setsockopt_bindx() is supposed to call this function.
498  */
499 static int sctp_send_asconf_add_ip(struct sock		*sk,
500 				   struct sockaddr	*addrs,
501 				   int 			addrcnt)
502 {
503 	struct net *net = sock_net(sk);
504 	struct sctp_sock		*sp;
505 	struct sctp_endpoint		*ep;
506 	struct sctp_association		*asoc;
507 	struct sctp_bind_addr		*bp;
508 	struct sctp_chunk		*chunk;
509 	struct sctp_sockaddr_entry	*laddr;
510 	union sctp_addr			*addr;
511 	union sctp_addr			saveaddr;
512 	void				*addr_buf;
513 	struct sctp_af			*af;
514 	struct list_head		*p;
515 	int 				i;
516 	int 				retval = 0;
517 
518 	if (!net->sctp.addip_enable)
519 		return retval;
520 
521 	sp = sctp_sk(sk);
522 	ep = sp->ep;
523 
524 	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
525 		 __func__, sk, addrs, addrcnt);
526 
527 	list_for_each_entry(asoc, &ep->asocs, asocs) {
528 		if (!asoc->peer.asconf_capable)
529 			continue;
530 
531 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
532 			continue;
533 
534 		if (!sctp_state(asoc, ESTABLISHED))
535 			continue;
536 
537 		/* Check if any address in the packed array of addresses is
538 		 * in the bind address list of the association. If so,
539 		 * do not send the asconf chunk to its peer, but continue with
540 		 * other associations.
541 		 */
542 		addr_buf = addrs;
543 		for (i = 0; i < addrcnt; i++) {
544 			addr = addr_buf;
545 			af = sctp_get_af_specific(addr->v4.sin_family);
546 			if (!af) {
547 				retval = -EINVAL;
548 				goto out;
549 			}
550 
551 			if (sctp_assoc_lookup_laddr(asoc, addr))
552 				break;
553 
554 			addr_buf += af->sockaddr_len;
555 		}
556 		if (i < addrcnt)
557 			continue;
558 
559 		/* Use the first valid address in bind addr list of
560 		 * association as Address Parameter of ASCONF CHUNK.
561 		 */
562 		bp = &asoc->base.bind_addr;
563 		p = bp->address_list.next;
564 		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
565 		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
566 						   addrcnt, SCTP_PARAM_ADD_IP);
567 		if (!chunk) {
568 			retval = -ENOMEM;
569 			goto out;
570 		}
571 
572 		/* Add the new addresses to the bind address list with
573 		 * use_as_src set to 0.
574 		 */
575 		addr_buf = addrs;
576 		for (i = 0; i < addrcnt; i++) {
577 			addr = addr_buf;
578 			af = sctp_get_af_specific(addr->v4.sin_family);
579 			memcpy(&saveaddr, addr, af->sockaddr_len);
580 			retval = sctp_add_bind_addr(bp, &saveaddr,
581 						    sizeof(saveaddr),
582 						    SCTP_ADDR_NEW, GFP_ATOMIC);
583 			addr_buf += af->sockaddr_len;
584 		}
585 		if (asoc->src_out_of_asoc_ok) {
586 			struct sctp_transport *trans;
587 
588 			list_for_each_entry(trans,
589 			    &asoc->peer.transport_addr_list, transports) {
590 				/* Clear the source and route cache */
591 				dst_release(trans->dst);
592 				trans->cwnd = min(4*asoc->pathmtu, max_t(__u32,
593 				    2*asoc->pathmtu, 4380));
594 				trans->ssthresh = asoc->peer.i.a_rwnd;
595 				trans->rto = asoc->rto_initial;
596 				sctp_max_rto(asoc, trans);
597 				trans->rtt = trans->srtt = trans->rttvar = 0;
598 				sctp_transport_route(trans, NULL,
599 				    sctp_sk(asoc->base.sk));
600 			}
601 		}
602 		retval = sctp_send_asconf(asoc, chunk);
603 	}
604 
605 out:
606 	return retval;
607 }
608 
609 /* Remove a list of addresses from bind addresses list.  Do not remove the
610  * last address.
611  *
612  * Basically run through each address specified in the addrs/addrcnt
613  * array/length pair, determine if it is IPv6 or IPv4 and call
614  * sctp_del_bind() on it.
615  *
616  * If any of them fails, then the operation will be reversed and the
617  * ones that were removed will be added back.
618  *
619  * At least one address has to be left; if only one address is
620  * available, the operation will return -EBUSY.
621  *
622  * Only sctp_setsockopt_bindx() is supposed to call this function.
623  */
624 static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
625 {
626 	struct sctp_sock *sp = sctp_sk(sk);
627 	struct sctp_endpoint *ep = sp->ep;
628 	int cnt;
629 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
630 	int retval = 0;
631 	void *addr_buf;
632 	union sctp_addr *sa_addr;
633 	struct sctp_af *af;
634 
635 	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
636 		 __func__, sk, addrs, addrcnt);
637 
638 	addr_buf = addrs;
639 	for (cnt = 0; cnt < addrcnt; cnt++) {
640 		/* If the bind address list is empty or if there is only one
641 		 * bind address, there is nothing more to be removed (we need
642 		 * at least one address here).
643 		 */
644 		if (list_empty(&bp->address_list) ||
645 		    (sctp_list_single_entry(&bp->address_list))) {
646 			retval = -EBUSY;
647 			goto err_bindx_rem;
648 		}
649 
650 		sa_addr = addr_buf;
651 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
652 		if (!af) {
653 			retval = -EINVAL;
654 			goto err_bindx_rem;
655 		}
656 
657 		if (!af->addr_valid(sa_addr, sp, NULL)) {
658 			retval = -EADDRNOTAVAIL;
659 			goto err_bindx_rem;
660 		}
661 
662 		if (sa_addr->v4.sin_port &&
663 		    sa_addr->v4.sin_port != htons(bp->port)) {
664 			retval = -EINVAL;
665 			goto err_bindx_rem;
666 		}
667 
668 		if (!sa_addr->v4.sin_port)
669 			sa_addr->v4.sin_port = htons(bp->port);
670 
671 		/* FIXME - There is probably a need to check if sk->sk_saddr and
672 		 * sk->sk_rcv_addr are currently set to one of the addresses to
673 		 * be removed. This is something which needs to be looked into
674 		 * when we are fixing the outstanding issues with multi-homing
675 		 * socket routing and failover schemes. Refer to comments in
676 		 * sctp_do_bind(). -daisy
677 		 */
678 		retval = sctp_del_bind_addr(bp, sa_addr);
679 
680 		addr_buf += af->sockaddr_len;
681 err_bindx_rem:
682 		if (retval < 0) {
683 			/* Failed. Add the ones that has been removed back */
684 			if (cnt > 0)
685 				sctp_bindx_add(sk, addrs, cnt);
686 			return retval;
687 		}
688 	}
689 
690 	return retval;
691 }
692 
693 /* Send an ASCONF chunk with Delete IP address parameters to all the peers of
694  * the associations that are part of the endpoint indicating that a list of
695  * local addresses are removed from the endpoint.
696  *
697  * If any of the addresses is already in the bind address list of the
698  * association, we do not send the chunk for that association.  But it will not
699  * affect other associations.
700  *
701  * Only sctp_setsockopt_bindx() is supposed to call this function.
702  */
703 static int sctp_send_asconf_del_ip(struct sock		*sk,
704 				   struct sockaddr	*addrs,
705 				   int			addrcnt)
706 {
707 	struct net *net = sock_net(sk);
708 	struct sctp_sock	*sp;
709 	struct sctp_endpoint	*ep;
710 	struct sctp_association	*asoc;
711 	struct sctp_transport	*transport;
712 	struct sctp_bind_addr	*bp;
713 	struct sctp_chunk	*chunk;
714 	union sctp_addr		*laddr;
715 	void			*addr_buf;
716 	struct sctp_af		*af;
717 	struct sctp_sockaddr_entry *saddr;
718 	int 			i;
719 	int 			retval = 0;
720 	int			stored = 0;
721 
722 	chunk = NULL;
723 	if (!net->sctp.addip_enable)
724 		return retval;
725 
726 	sp = sctp_sk(sk);
727 	ep = sp->ep;
728 
729 	pr_debug("%s: sk:%p, addrs:%p, addrcnt:%d\n",
730 		 __func__, sk, addrs, addrcnt);
731 
732 	list_for_each_entry(asoc, &ep->asocs, asocs) {
733 
734 		if (!asoc->peer.asconf_capable)
735 			continue;
736 
737 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
738 			continue;
739 
740 		if (!sctp_state(asoc, ESTABLISHED))
741 			continue;
742 
743 		/* Check if any address in the packed array of addresses is
744 		 * not present in the bind address list of the association.
745 		 * If so, do not send the asconf chunk to its peer, but
746 		 * continue with other associations.
747 		 */
748 		addr_buf = addrs;
749 		for (i = 0; i < addrcnt; i++) {
750 			laddr = addr_buf;
751 			af = sctp_get_af_specific(laddr->v4.sin_family);
752 			if (!af) {
753 				retval = -EINVAL;
754 				goto out;
755 			}
756 
757 			if (!sctp_assoc_lookup_laddr(asoc, laddr))
758 				break;
759 
760 			addr_buf += af->sockaddr_len;
761 		}
762 		if (i < addrcnt)
763 			continue;
764 
765 		/* Find one address in the association's bind address list
766 		 * that is not in the packed array of addresses. This is to
767 		 * make sure that we do not delete all the addresses in the
768 		 * association.
769 		 */
770 		bp = &asoc->base.bind_addr;
771 		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
772 					       addrcnt, sp);
773 		if ((laddr == NULL) && (addrcnt == 1)) {
774 			if (asoc->asconf_addr_del_pending)
775 				continue;
776 			asoc->asconf_addr_del_pending =
777 			    kzalloc(sizeof(union sctp_addr), GFP_ATOMIC);
778 			if (asoc->asconf_addr_del_pending == NULL) {
779 				retval = -ENOMEM;
780 				goto out;
781 			}
782 			asoc->asconf_addr_del_pending->sa.sa_family =
783 				    addrs->sa_family;
784 			asoc->asconf_addr_del_pending->v4.sin_port =
785 				    htons(bp->port);
786 			if (addrs->sa_family == AF_INET) {
787 				struct sockaddr_in *sin;
788 
789 				sin = (struct sockaddr_in *)addrs;
790 				asoc->asconf_addr_del_pending->v4.sin_addr.s_addr = sin->sin_addr.s_addr;
791 			} else if (addrs->sa_family == AF_INET6) {
792 				struct sockaddr_in6 *sin6;
793 
794 				sin6 = (struct sockaddr_in6 *)addrs;
795 				asoc->asconf_addr_del_pending->v6.sin6_addr = sin6->sin6_addr;
796 			}
797 
798 			pr_debug("%s: keep the last address asoc:%p %pISc at %p\n",
799 				 __func__, asoc, &asoc->asconf_addr_del_pending->sa,
800 				 asoc->asconf_addr_del_pending);
801 
802 			asoc->src_out_of_asoc_ok = 1;
803 			stored = 1;
804 			goto skip_mkasconf;
805 		}
806 
807 		if (laddr == NULL)
808 			return -EINVAL;
809 
810 		/* We do not need RCU protection throughout this loop
811 		 * because this is done under a socket lock from the
812 		 * setsockopt call.
813 		 */
814 		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
815 						   SCTP_PARAM_DEL_IP);
816 		if (!chunk) {
817 			retval = -ENOMEM;
818 			goto out;
819 		}
820 
821 skip_mkasconf:
822 		/* Reset use_as_src flag for the addresses in the bind address
823 		 * list that are to be deleted.
824 		 */
825 		addr_buf = addrs;
826 		for (i = 0; i < addrcnt; i++) {
827 			laddr = addr_buf;
828 			af = sctp_get_af_specific(laddr->v4.sin_family);
829 			list_for_each_entry(saddr, &bp->address_list, list) {
830 				if (sctp_cmp_addr_exact(&saddr->a, laddr))
831 					saddr->state = SCTP_ADDR_DEL;
832 			}
833 			addr_buf += af->sockaddr_len;
834 		}
835 
836 		/* Update the route and saddr entries for all the transports
837 		 * as some of the addresses in the bind address list are
838 		 * about to be deleted and cannot be used as source addresses.
839 		 */
840 		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
841 					transports) {
842 			dst_release(transport->dst);
843 			sctp_transport_route(transport, NULL,
844 					     sctp_sk(asoc->base.sk));
845 		}
846 
847 		if (stored)
848 			/* We don't need to transmit ASCONF */
849 			continue;
850 		retval = sctp_send_asconf(asoc, chunk);
851 	}
852 out:
853 	return retval;
854 }
855 
856 /* set addr events to assocs in the endpoint.  ep and addr_wq must be locked */
857 int sctp_asconf_mgmt(struct sctp_sock *sp, struct sctp_sockaddr_entry *addrw)
858 {
859 	struct sock *sk = sctp_opt2sk(sp);
860 	union sctp_addr *addr;
861 	struct sctp_af *af;
862 
863 	/* It is safe to write port space in caller. */
864 	addr = &addrw->a;
865 	addr->v4.sin_port = htons(sp->ep->base.bind_addr.port);
866 	af = sctp_get_af_specific(addr->sa.sa_family);
867 	if (!af)
868 		return -EINVAL;
869 	if (sctp_verify_addr(sk, addr, af->sockaddr_len))
870 		return -EINVAL;
871 
872 	if (addrw->state == SCTP_ADDR_NEW)
873 		return sctp_send_asconf_add_ip(sk, (struct sockaddr *)addr, 1);
874 	else
875 		return sctp_send_asconf_del_ip(sk, (struct sockaddr *)addr, 1);
876 }
877 
878 /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
879  *
880  * API 8.1
881  * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt,
882  *                int flags);
883  *
884  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
885  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
886  * or IPv6 addresses.
887  *
888  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
889  * Section 3.1.2 for this usage.
890  *
891  * addrs is a pointer to an array of one or more socket addresses. Each
892  * address is contained in its appropriate structure (i.e. struct
893  * sockaddr_in or struct sockaddr_in6) the family of the address type
894  * must be used to distinguish the address length (note that this
895  * representation is termed a "packed array" of addresses). The caller
896  * specifies the number of addresses in the array with addrcnt.
897  *
898  * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns
899  * -1, and sets errno to the appropriate error code.
900  *
901  * For SCTP, the port given in each socket address must be the same, or
902  * sctp_bindx() will fail, setting errno to EINVAL.
903  *
904  * The flags parameter is formed from the bitwise OR of zero or more of
905  * the following currently defined flags:
906  *
907  * SCTP_BINDX_ADD_ADDR
908  *
909  * SCTP_BINDX_REM_ADDR
910  *
911  * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
912  * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given
913  * addresses from the association. The two flags are mutually exclusive;
914  * if both are given, sctp_bindx() will fail with EINVAL. A caller may
915  * not remove all addresses from an association; sctp_bindx() will
916  * reject such an attempt with EINVAL.
917  *
918  * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
919  * additional addresses with an endpoint after calling bind().  Or use
920  * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
921  * socket is associated with so that no new association accepted will be
922  * associated with those addresses. If the endpoint supports dynamic
923  * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
924  * endpoint to send the appropriate message to the peer to change the
925  * peers address lists.
926  *
927  * Adding and removing addresses from a connected association is
928  * optional functionality. Implementations that do not support this
929  * functionality should return EOPNOTSUPP.
930  *
931  * Basically do nothing but copying the addresses from user to kernel
932  * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
933  * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
934  * from userspace.
935  *
936  * We don't use copy_from_user() for optimization: we first do the
937  * sanity checks (buffer size -fast- and access check-healthy
938  * pointer); if all of those succeed, then we can alloc the memory
939  * (expensive operation) needed to copy the data to kernel. Then we do
940  * the copying without checking the user space area
941  * (__copy_from_user()).
942  *
943  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
944  * it.
945  *
946  * sk        The sk of the socket
947  * addrs     The pointer to the addresses in user land
948  * addrssize Size of the addrs buffer
949  * op        Operation to perform (add or remove, see the flags of
950  *           sctp_bindx)
951  *
952  * Returns 0 if ok, <0 errno code on error.
953  */
954 static int sctp_setsockopt_bindx(struct sock *sk,
955 				 struct sockaddr __user *addrs,
956 				 int addrs_size, int op)
957 {
958 	struct sockaddr *kaddrs;
959 	int err;
960 	int addrcnt = 0;
961 	int walk_size = 0;
962 	struct sockaddr *sa_addr;
963 	void *addr_buf;
964 	struct sctp_af *af;
965 
966 	pr_debug("%s: sk:%p addrs:%p addrs_size:%d opt:%d\n",
967 		 __func__, sk, addrs, addrs_size, op);
968 
969 	if (unlikely(addrs_size <= 0))
970 		return -EINVAL;
971 
972 	/* Check the user passed a healthy pointer.  */
973 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
974 		return -EFAULT;
975 
976 	/* Alloc space for the address array in kernel memory.  */
977 	kaddrs = kmalloc(addrs_size, GFP_USER | __GFP_NOWARN);
978 	if (unlikely(!kaddrs))
979 		return -ENOMEM;
980 
981 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
982 		kfree(kaddrs);
983 		return -EFAULT;
984 	}
985 
986 	/* Walk through the addrs buffer and count the number of addresses. */
987 	addr_buf = kaddrs;
988 	while (walk_size < addrs_size) {
989 		if (walk_size + sizeof(sa_family_t) > addrs_size) {
990 			kfree(kaddrs);
991 			return -EINVAL;
992 		}
993 
994 		sa_addr = addr_buf;
995 		af = sctp_get_af_specific(sa_addr->sa_family);
996 
997 		/* If the address family is not supported or if this address
998 		 * causes the address buffer to overflow return EINVAL.
999 		 */
1000 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1001 			kfree(kaddrs);
1002 			return -EINVAL;
1003 		}
1004 		addrcnt++;
1005 		addr_buf += af->sockaddr_len;
1006 		walk_size += af->sockaddr_len;
1007 	}
1008 
1009 	/* Do the work. */
1010 	switch (op) {
1011 	case SCTP_BINDX_ADD_ADDR:
1012 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
1013 		if (err)
1014 			goto out;
1015 		err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
1016 		break;
1017 
1018 	case SCTP_BINDX_REM_ADDR:
1019 		err = sctp_bindx_rem(sk, kaddrs, addrcnt);
1020 		if (err)
1021 			goto out;
1022 		err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
1023 		break;
1024 
1025 	default:
1026 		err = -EINVAL;
1027 		break;
1028 	}
1029 
1030 out:
1031 	kfree(kaddrs);
1032 
1033 	return err;
1034 }
1035 
1036 /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
1037  *
1038  * Common routine for handling connect() and sctp_connectx().
1039  * Connect will come in with just a single address.
1040  */
1041 static int __sctp_connect(struct sock *sk,
1042 			  struct sockaddr *kaddrs,
1043 			  int addrs_size,
1044 			  sctp_assoc_t *assoc_id)
1045 {
1046 	struct net *net = sock_net(sk);
1047 	struct sctp_sock *sp;
1048 	struct sctp_endpoint *ep;
1049 	struct sctp_association *asoc = NULL;
1050 	struct sctp_association *asoc2;
1051 	struct sctp_transport *transport;
1052 	union sctp_addr to;
1053 	sctp_scope_t scope;
1054 	long timeo;
1055 	int err = 0;
1056 	int addrcnt = 0;
1057 	int walk_size = 0;
1058 	union sctp_addr *sa_addr = NULL;
1059 	void *addr_buf;
1060 	unsigned short port;
1061 	unsigned int f_flags = 0;
1062 
1063 	sp = sctp_sk(sk);
1064 	ep = sp->ep;
1065 
1066 	/* connect() cannot be done on a socket that is already in ESTABLISHED
1067 	 * state - UDP-style peeled off socket or a TCP-style socket that
1068 	 * is already connected.
1069 	 * It cannot be done even on a TCP-style listening socket.
1070 	 */
1071 	if (sctp_sstate(sk, ESTABLISHED) || sctp_sstate(sk, CLOSING) ||
1072 	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
1073 		err = -EISCONN;
1074 		goto out_free;
1075 	}
1076 
1077 	/* Walk through the addrs buffer and count the number of addresses. */
1078 	addr_buf = kaddrs;
1079 	while (walk_size < addrs_size) {
1080 		struct sctp_af *af;
1081 
1082 		if (walk_size + sizeof(sa_family_t) > addrs_size) {
1083 			err = -EINVAL;
1084 			goto out_free;
1085 		}
1086 
1087 		sa_addr = addr_buf;
1088 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
1089 
1090 		/* If the address family is not supported or if this address
1091 		 * causes the address buffer to overflow return EINVAL.
1092 		 */
1093 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1094 			err = -EINVAL;
1095 			goto out_free;
1096 		}
1097 
1098 		port = ntohs(sa_addr->v4.sin_port);
1099 
1100 		/* Save current address so we can work with it */
1101 		memcpy(&to, sa_addr, af->sockaddr_len);
1102 
1103 		err = sctp_verify_addr(sk, &to, af->sockaddr_len);
1104 		if (err)
1105 			goto out_free;
1106 
1107 		/* Make sure the destination port is correctly set
1108 		 * in all addresses.
1109 		 */
1110 		if (asoc && asoc->peer.port && asoc->peer.port != port) {
1111 			err = -EINVAL;
1112 			goto out_free;
1113 		}
1114 
1115 		/* Check if there already is a matching association on the
1116 		 * endpoint (other than the one created here).
1117 		 */
1118 		asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1119 		if (asoc2 && asoc2 != asoc) {
1120 			if (asoc2->state >= SCTP_STATE_ESTABLISHED)
1121 				err = -EISCONN;
1122 			else
1123 				err = -EALREADY;
1124 			goto out_free;
1125 		}
1126 
1127 		/* If we could not find a matching association on the endpoint,
1128 		 * make sure that there is no peeled-off association matching
1129 		 * the peer address even on another socket.
1130 		 */
1131 		if (sctp_endpoint_is_peeled_off(ep, &to)) {
1132 			err = -EADDRNOTAVAIL;
1133 			goto out_free;
1134 		}
1135 
1136 		if (!asoc) {
1137 			/* If a bind() or sctp_bindx() is not called prior to
1138 			 * an sctp_connectx() call, the system picks an
1139 			 * ephemeral port and will choose an address set
1140 			 * equivalent to binding with a wildcard address.
1141 			 */
1142 			if (!ep->base.bind_addr.port) {
1143 				if (sctp_autobind(sk)) {
1144 					err = -EAGAIN;
1145 					goto out_free;
1146 				}
1147 			} else {
1148 				/*
1149 				 * If an unprivileged user inherits a 1-many
1150 				 * style socket with open associations on a
1151 				 * privileged port, it MAY be permitted to
1152 				 * accept new associations, but it SHOULD NOT
1153 				 * be permitted to open new associations.
1154 				 */
1155 				if (ep->base.bind_addr.port < PROT_SOCK &&
1156 				    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) {
1157 					err = -EACCES;
1158 					goto out_free;
1159 				}
1160 			}
1161 
1162 			scope = sctp_scope(&to);
1163 			asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1164 			if (!asoc) {
1165 				err = -ENOMEM;
1166 				goto out_free;
1167 			}
1168 
1169 			err = sctp_assoc_set_bind_addr_from_ep(asoc, scope,
1170 							      GFP_KERNEL);
1171 			if (err < 0) {
1172 				goto out_free;
1173 			}
1174 
1175 		}
1176 
1177 		/* Prime the peer's transport structures.  */
1178 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL,
1179 						SCTP_UNKNOWN);
1180 		if (!transport) {
1181 			err = -ENOMEM;
1182 			goto out_free;
1183 		}
1184 
1185 		addrcnt++;
1186 		addr_buf += af->sockaddr_len;
1187 		walk_size += af->sockaddr_len;
1188 	}
1189 
1190 	/* In case the user of sctp_connectx() wants an association
1191 	 * id back, assign one now.
1192 	 */
1193 	if (assoc_id) {
1194 		err = sctp_assoc_set_id(asoc, GFP_KERNEL);
1195 		if (err < 0)
1196 			goto out_free;
1197 	}
1198 
1199 	err = sctp_primitive_ASSOCIATE(net, asoc, NULL);
1200 	if (err < 0) {
1201 		goto out_free;
1202 	}
1203 
1204 	/* Initialize sk's dport and daddr for getpeername() */
1205 	inet_sk(sk)->inet_dport = htons(asoc->peer.port);
1206 	sp->pf->to_sk_daddr(sa_addr, sk);
1207 	sk->sk_err = 0;
1208 
1209 	/* in-kernel sockets don't generally have a file allocated to them
1210 	 * if all they do is call sock_create_kern().
1211 	 */
1212 	if (sk->sk_socket->file)
1213 		f_flags = sk->sk_socket->file->f_flags;
1214 
1215 	timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK);
1216 
1217 	if (assoc_id)
1218 		*assoc_id = asoc->assoc_id;
1219 	err = sctp_wait_for_connect(asoc, &timeo);
1220 	/* Note: the asoc may be freed after the return of
1221 	 * sctp_wait_for_connect.
1222 	 */
1223 
1224 	/* Don't free association on exit. */
1225 	asoc = NULL;
1226 
1227 out_free:
1228 	pr_debug("%s: took out_free path with asoc:%p kaddrs:%p err:%d\n",
1229 		 __func__, asoc, kaddrs, err);
1230 
1231 	if (asoc) {
1232 		/* sctp_primitive_ASSOCIATE may have added this association
1233 		 * To the hash table, try to unhash it, just in case, its a noop
1234 		 * if it wasn't hashed so we're safe
1235 		 */
1236 		sctp_association_free(asoc);
1237 	}
1238 	return err;
1239 }
1240 
1241 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
1242  *
1243  * API 8.9
1244  * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt,
1245  * 			sctp_assoc_t *asoc);
1246  *
1247  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
1248  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
1249  * or IPv6 addresses.
1250  *
1251  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
1252  * Section 3.1.2 for this usage.
1253  *
1254  * addrs is a pointer to an array of one or more socket addresses. Each
1255  * address is contained in its appropriate structure (i.e. struct
1256  * sockaddr_in or struct sockaddr_in6) the family of the address type
1257  * must be used to distengish the address length (note that this
1258  * representation is termed a "packed array" of addresses). The caller
1259  * specifies the number of addresses in the array with addrcnt.
1260  *
1261  * On success, sctp_connectx() returns 0. It also sets the assoc_id to
1262  * the association id of the new association.  On failure, sctp_connectx()
1263  * returns -1, and sets errno to the appropriate error code.  The assoc_id
1264  * is not touched by the kernel.
1265  *
1266  * For SCTP, the port given in each socket address must be the same, or
1267  * sctp_connectx() will fail, setting errno to EINVAL.
1268  *
1269  * An application can use sctp_connectx to initiate an association with
1270  * an endpoint that is multi-homed.  Much like sctp_bindx() this call
1271  * allows a caller to specify multiple addresses at which a peer can be
1272  * reached.  The way the SCTP stack uses the list of addresses to set up
1273  * the association is implementation dependent.  This function only
1274  * specifies that the stack will try to make use of all the addresses in
1275  * the list when needed.
1276  *
1277  * Note that the list of addresses passed in is only used for setting up
1278  * the association.  It does not necessarily equal the set of addresses
1279  * the peer uses for the resulting association.  If the caller wants to
1280  * find out the set of peer addresses, it must use sctp_getpaddrs() to
1281  * retrieve them after the association has been set up.
1282  *
1283  * Basically do nothing but copying the addresses from user to kernel
1284  * land and invoking either sctp_connectx(). This is used for tunneling
1285  * the sctp_connectx() request through sctp_setsockopt() from userspace.
1286  *
1287  * We don't use copy_from_user() for optimization: we first do the
1288  * sanity checks (buffer size -fast- and access check-healthy
1289  * pointer); if all of those succeed, then we can alloc the memory
1290  * (expensive operation) needed to copy the data to kernel. Then we do
1291  * the copying without checking the user space area
1292  * (__copy_from_user()).
1293  *
1294  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
1295  * it.
1296  *
1297  * sk        The sk of the socket
1298  * addrs     The pointer to the addresses in user land
1299  * addrssize Size of the addrs buffer
1300  *
1301  * Returns >=0 if ok, <0 errno code on error.
1302  */
1303 static int __sctp_setsockopt_connectx(struct sock *sk,
1304 				      struct sockaddr __user *addrs,
1305 				      int addrs_size,
1306 				      sctp_assoc_t *assoc_id)
1307 {
1308 	struct sockaddr *kaddrs;
1309 	gfp_t gfp = GFP_KERNEL;
1310 	int err = 0;
1311 
1312 	pr_debug("%s: sk:%p addrs:%p addrs_size:%d\n",
1313 		 __func__, sk, addrs, addrs_size);
1314 
1315 	if (unlikely(addrs_size <= 0))
1316 		return -EINVAL;
1317 
1318 	/* Check the user passed a healthy pointer.  */
1319 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
1320 		return -EFAULT;
1321 
1322 	/* Alloc space for the address array in kernel memory.  */
1323 	if (sk->sk_socket->file)
1324 		gfp = GFP_USER | __GFP_NOWARN;
1325 	kaddrs = kmalloc(addrs_size, gfp);
1326 	if (unlikely(!kaddrs))
1327 		return -ENOMEM;
1328 
1329 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
1330 		err = -EFAULT;
1331 	} else {
1332 		err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
1333 	}
1334 
1335 	kfree(kaddrs);
1336 
1337 	return err;
1338 }
1339 
1340 /*
1341  * This is an older interface.  It's kept for backward compatibility
1342  * to the option that doesn't provide association id.
1343  */
1344 static int sctp_setsockopt_connectx_old(struct sock *sk,
1345 					struct sockaddr __user *addrs,
1346 					int addrs_size)
1347 {
1348 	return __sctp_setsockopt_connectx(sk, addrs, addrs_size, NULL);
1349 }
1350 
1351 /*
1352  * New interface for the API.  The since the API is done with a socket
1353  * option, to make it simple we feed back the association id is as a return
1354  * indication to the call.  Error is always negative and association id is
1355  * always positive.
1356  */
1357 static int sctp_setsockopt_connectx(struct sock *sk,
1358 				    struct sockaddr __user *addrs,
1359 				    int addrs_size)
1360 {
1361 	sctp_assoc_t assoc_id = 0;
1362 	int err = 0;
1363 
1364 	err = __sctp_setsockopt_connectx(sk, addrs, addrs_size, &assoc_id);
1365 
1366 	if (err)
1367 		return err;
1368 	else
1369 		return assoc_id;
1370 }
1371 
1372 /*
1373  * New (hopefully final) interface for the API.
1374  * We use the sctp_getaddrs_old structure so that use-space library
1375  * can avoid any unnecessary allocations. The only different part
1376  * is that we store the actual length of the address buffer into the
1377  * addrs_num structure member. That way we can re-use the existing
1378  * code.
1379  */
1380 #ifdef CONFIG_COMPAT
1381 struct compat_sctp_getaddrs_old {
1382 	sctp_assoc_t	assoc_id;
1383 	s32		addr_num;
1384 	compat_uptr_t	addrs;		/* struct sockaddr * */
1385 };
1386 #endif
1387 
1388 static int sctp_getsockopt_connectx3(struct sock *sk, int len,
1389 				     char __user *optval,
1390 				     int __user *optlen)
1391 {
1392 	struct sctp_getaddrs_old param;
1393 	sctp_assoc_t assoc_id = 0;
1394 	int err = 0;
1395 
1396 #ifdef CONFIG_COMPAT
1397 	if (in_compat_syscall()) {
1398 		struct compat_sctp_getaddrs_old param32;
1399 
1400 		if (len < sizeof(param32))
1401 			return -EINVAL;
1402 		if (copy_from_user(&param32, optval, sizeof(param32)))
1403 			return -EFAULT;
1404 
1405 		param.assoc_id = param32.assoc_id;
1406 		param.addr_num = param32.addr_num;
1407 		param.addrs = compat_ptr(param32.addrs);
1408 	} else
1409 #endif
1410 	{
1411 		if (len < sizeof(param))
1412 			return -EINVAL;
1413 		if (copy_from_user(&param, optval, sizeof(param)))
1414 			return -EFAULT;
1415 	}
1416 
1417 	err = __sctp_setsockopt_connectx(sk, (struct sockaddr __user *)
1418 					 param.addrs, param.addr_num,
1419 					 &assoc_id);
1420 	if (err == 0 || err == -EINPROGRESS) {
1421 		if (copy_to_user(optval, &assoc_id, sizeof(assoc_id)))
1422 			return -EFAULT;
1423 		if (put_user(sizeof(assoc_id), optlen))
1424 			return -EFAULT;
1425 	}
1426 
1427 	return err;
1428 }
1429 
1430 /* API 3.1.4 close() - UDP Style Syntax
1431  * Applications use close() to perform graceful shutdown (as described in
1432  * Section 10.1 of [SCTP]) on ALL the associations currently represented
1433  * by a UDP-style socket.
1434  *
1435  * The syntax is
1436  *
1437  *   ret = close(int sd);
1438  *
1439  *   sd      - the socket descriptor of the associations to be closed.
1440  *
1441  * To gracefully shutdown a specific association represented by the
1442  * UDP-style socket, an application should use the sendmsg() call,
1443  * passing no user data, but including the appropriate flag in the
1444  * ancillary data (see Section xxxx).
1445  *
1446  * If sd in the close() call is a branched-off socket representing only
1447  * one association, the shutdown is performed on that association only.
1448  *
1449  * 4.1.6 close() - TCP Style Syntax
1450  *
1451  * Applications use close() to gracefully close down an association.
1452  *
1453  * The syntax is:
1454  *
1455  *    int close(int sd);
1456  *
1457  *      sd      - the socket descriptor of the association to be closed.
1458  *
1459  * After an application calls close() on a socket descriptor, no further
1460  * socket operations will succeed on that descriptor.
1461  *
1462  * API 7.1.4 SO_LINGER
1463  *
1464  * An application using the TCP-style socket can use this option to
1465  * perform the SCTP ABORT primitive.  The linger option structure is:
1466  *
1467  *  struct  linger {
1468  *     int     l_onoff;                // option on/off
1469  *     int     l_linger;               // linger time
1470  * };
1471  *
1472  * To enable the option, set l_onoff to 1.  If the l_linger value is set
1473  * to 0, calling close() is the same as the ABORT primitive.  If the
1474  * value is set to a negative value, the setsockopt() call will return
1475  * an error.  If the value is set to a positive value linger_time, the
1476  * close() can be blocked for at most linger_time ms.  If the graceful
1477  * shutdown phase does not finish during this period, close() will
1478  * return but the graceful shutdown phase continues in the system.
1479  */
1480 static void sctp_close(struct sock *sk, long timeout)
1481 {
1482 	struct net *net = sock_net(sk);
1483 	struct sctp_endpoint *ep;
1484 	struct sctp_association *asoc;
1485 	struct list_head *pos, *temp;
1486 	unsigned int data_was_unread;
1487 
1488 	pr_debug("%s: sk:%p, timeout:%ld\n", __func__, sk, timeout);
1489 
1490 	lock_sock(sk);
1491 	sk->sk_shutdown = SHUTDOWN_MASK;
1492 	sk->sk_state = SCTP_SS_CLOSING;
1493 
1494 	ep = sctp_sk(sk)->ep;
1495 
1496 	/* Clean up any skbs sitting on the receive queue.  */
1497 	data_was_unread = sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
1498 	data_was_unread += sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
1499 
1500 	/* Walk all associations on an endpoint.  */
1501 	list_for_each_safe(pos, temp, &ep->asocs) {
1502 		asoc = list_entry(pos, struct sctp_association, asocs);
1503 
1504 		if (sctp_style(sk, TCP)) {
1505 			/* A closed association can still be in the list if
1506 			 * it belongs to a TCP-style listening socket that is
1507 			 * not yet accepted. If so, free it. If not, send an
1508 			 * ABORT or SHUTDOWN based on the linger options.
1509 			 */
1510 			if (sctp_state(asoc, CLOSED)) {
1511 				sctp_association_free(asoc);
1512 				continue;
1513 			}
1514 		}
1515 
1516 		if (data_was_unread || !skb_queue_empty(&asoc->ulpq.lobby) ||
1517 		    !skb_queue_empty(&asoc->ulpq.reasm) ||
1518 		    (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime)) {
1519 			struct sctp_chunk *chunk;
1520 
1521 			chunk = sctp_make_abort_user(asoc, NULL, 0);
1522 			sctp_primitive_ABORT(net, asoc, chunk);
1523 		} else
1524 			sctp_primitive_SHUTDOWN(net, asoc, NULL);
1525 	}
1526 
1527 	/* On a TCP-style socket, block for at most linger_time if set. */
1528 	if (sctp_style(sk, TCP) && timeout)
1529 		sctp_wait_for_close(sk, timeout);
1530 
1531 	/* This will run the backlog queue.  */
1532 	release_sock(sk);
1533 
1534 	/* Supposedly, no process has access to the socket, but
1535 	 * the net layers still may.
1536 	 * Also, sctp_destroy_sock() needs to be called with addr_wq_lock
1537 	 * held and that should be grabbed before socket lock.
1538 	 */
1539 	spin_lock_bh(&net->sctp.addr_wq_lock);
1540 	bh_lock_sock(sk);
1541 
1542 	/* Hold the sock, since sk_common_release() will put sock_put()
1543 	 * and we have just a little more cleanup.
1544 	 */
1545 	sock_hold(sk);
1546 	sk_common_release(sk);
1547 
1548 	bh_unlock_sock(sk);
1549 	spin_unlock_bh(&net->sctp.addr_wq_lock);
1550 
1551 	sock_put(sk);
1552 
1553 	SCTP_DBG_OBJCNT_DEC(sock);
1554 }
1555 
1556 /* Handle EPIPE error. */
1557 static int sctp_error(struct sock *sk, int flags, int err)
1558 {
1559 	if (err == -EPIPE)
1560 		err = sock_error(sk) ? : -EPIPE;
1561 	if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
1562 		send_sig(SIGPIPE, current, 0);
1563 	return err;
1564 }
1565 
1566 /* API 3.1.3 sendmsg() - UDP Style Syntax
1567  *
1568  * An application uses sendmsg() and recvmsg() calls to transmit data to
1569  * and receive data from its peer.
1570  *
1571  *  ssize_t sendmsg(int socket, const struct msghdr *message,
1572  *                  int flags);
1573  *
1574  *  socket  - the socket descriptor of the endpoint.
1575  *  message - pointer to the msghdr structure which contains a single
1576  *            user message and possibly some ancillary data.
1577  *
1578  *            See Section 5 for complete description of the data
1579  *            structures.
1580  *
1581  *  flags   - flags sent or received with the user message, see Section
1582  *            5 for complete description of the flags.
1583  *
1584  * Note:  This function could use a rewrite especially when explicit
1585  * connect support comes in.
1586  */
1587 /* BUG:  We do not implement the equivalent of sk_stream_wait_memory(). */
1588 
1589 static int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
1590 
1591 static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
1592 {
1593 	struct net *net = sock_net(sk);
1594 	struct sctp_sock *sp;
1595 	struct sctp_endpoint *ep;
1596 	struct sctp_association *new_asoc = NULL, *asoc = NULL;
1597 	struct sctp_transport *transport, *chunk_tp;
1598 	struct sctp_chunk *chunk;
1599 	union sctp_addr to;
1600 	struct sockaddr *msg_name = NULL;
1601 	struct sctp_sndrcvinfo default_sinfo;
1602 	struct sctp_sndrcvinfo *sinfo;
1603 	struct sctp_initmsg *sinit;
1604 	sctp_assoc_t associd = 0;
1605 	sctp_cmsgs_t cmsgs = { NULL };
1606 	sctp_scope_t scope;
1607 	bool fill_sinfo_ttl = false, wait_connect = false;
1608 	struct sctp_datamsg *datamsg;
1609 	int msg_flags = msg->msg_flags;
1610 	__u16 sinfo_flags = 0;
1611 	long timeo;
1612 	int err;
1613 
1614 	err = 0;
1615 	sp = sctp_sk(sk);
1616 	ep = sp->ep;
1617 
1618 	pr_debug("%s: sk:%p, msg:%p, msg_len:%zu ep:%p\n", __func__, sk,
1619 		 msg, msg_len, ep);
1620 
1621 	/* We cannot send a message over a TCP-style listening socket. */
1622 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) {
1623 		err = -EPIPE;
1624 		goto out_nounlock;
1625 	}
1626 
1627 	/* Parse out the SCTP CMSGs.  */
1628 	err = sctp_msghdr_parse(msg, &cmsgs);
1629 	if (err) {
1630 		pr_debug("%s: msghdr parse err:%x\n", __func__, err);
1631 		goto out_nounlock;
1632 	}
1633 
1634 	/* Fetch the destination address for this packet.  This
1635 	 * address only selects the association--it is not necessarily
1636 	 * the address we will send to.
1637 	 * For a peeled-off socket, msg_name is ignored.
1638 	 */
1639 	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
1640 		int msg_namelen = msg->msg_namelen;
1641 
1642 		err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
1643 				       msg_namelen);
1644 		if (err)
1645 			return err;
1646 
1647 		if (msg_namelen > sizeof(to))
1648 			msg_namelen = sizeof(to);
1649 		memcpy(&to, msg->msg_name, msg_namelen);
1650 		msg_name = msg->msg_name;
1651 	}
1652 
1653 	sinit = cmsgs.init;
1654 	if (cmsgs.sinfo != NULL) {
1655 		memset(&default_sinfo, 0, sizeof(default_sinfo));
1656 		default_sinfo.sinfo_stream = cmsgs.sinfo->snd_sid;
1657 		default_sinfo.sinfo_flags = cmsgs.sinfo->snd_flags;
1658 		default_sinfo.sinfo_ppid = cmsgs.sinfo->snd_ppid;
1659 		default_sinfo.sinfo_context = cmsgs.sinfo->snd_context;
1660 		default_sinfo.sinfo_assoc_id = cmsgs.sinfo->snd_assoc_id;
1661 
1662 		sinfo = &default_sinfo;
1663 		fill_sinfo_ttl = true;
1664 	} else {
1665 		sinfo = cmsgs.srinfo;
1666 	}
1667 	/* Did the user specify SNDINFO/SNDRCVINFO? */
1668 	if (sinfo) {
1669 		sinfo_flags = sinfo->sinfo_flags;
1670 		associd = sinfo->sinfo_assoc_id;
1671 	}
1672 
1673 	pr_debug("%s: msg_len:%zu, sinfo_flags:0x%x\n", __func__,
1674 		 msg_len, sinfo_flags);
1675 
1676 	/* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */
1677 	if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) {
1678 		err = -EINVAL;
1679 		goto out_nounlock;
1680 	}
1681 
1682 	/* If SCTP_EOF is set, no data can be sent. Disallow sending zero
1683 	 * length messages when SCTP_EOF|SCTP_ABORT is not set.
1684 	 * If SCTP_ABORT is set, the message length could be non zero with
1685 	 * the msg_iov set to the user abort reason.
1686 	 */
1687 	if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) ||
1688 	    (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) {
1689 		err = -EINVAL;
1690 		goto out_nounlock;
1691 	}
1692 
1693 	/* If SCTP_ADDR_OVER is set, there must be an address
1694 	 * specified in msg_name.
1695 	 */
1696 	if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) {
1697 		err = -EINVAL;
1698 		goto out_nounlock;
1699 	}
1700 
1701 	transport = NULL;
1702 
1703 	pr_debug("%s: about to look up association\n", __func__);
1704 
1705 	lock_sock(sk);
1706 
1707 	/* If a msg_name has been specified, assume this is to be used.  */
1708 	if (msg_name) {
1709 		/* Look for a matching association on the endpoint. */
1710 		asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1711 
1712 		/* If we could not find a matching association on the
1713 		 * endpoint, make sure that it is not a TCP-style
1714 		 * socket that already has an association or there is
1715 		 * no peeled-off association on another socket.
1716 		 */
1717 		if (!asoc &&
1718 		    ((sctp_style(sk, TCP) &&
1719 		      (sctp_sstate(sk, ESTABLISHED) ||
1720 		       sctp_sstate(sk, CLOSING))) ||
1721 		     sctp_endpoint_is_peeled_off(ep, &to))) {
1722 			err = -EADDRNOTAVAIL;
1723 			goto out_unlock;
1724 		}
1725 	} else {
1726 		asoc = sctp_id2assoc(sk, associd);
1727 		if (!asoc) {
1728 			err = -EPIPE;
1729 			goto out_unlock;
1730 		}
1731 	}
1732 
1733 	if (asoc) {
1734 		pr_debug("%s: just looked up association:%p\n", __func__, asoc);
1735 
1736 		/* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED
1737 		 * socket that has an association in CLOSED state. This can
1738 		 * happen when an accepted socket has an association that is
1739 		 * already CLOSED.
1740 		 */
1741 		if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) {
1742 			err = -EPIPE;
1743 			goto out_unlock;
1744 		}
1745 
1746 		if (sinfo_flags & SCTP_EOF) {
1747 			pr_debug("%s: shutting down association:%p\n",
1748 				 __func__, asoc);
1749 
1750 			sctp_primitive_SHUTDOWN(net, asoc, NULL);
1751 			err = 0;
1752 			goto out_unlock;
1753 		}
1754 		if (sinfo_flags & SCTP_ABORT) {
1755 
1756 			chunk = sctp_make_abort_user(asoc, msg, msg_len);
1757 			if (!chunk) {
1758 				err = -ENOMEM;
1759 				goto out_unlock;
1760 			}
1761 
1762 			pr_debug("%s: aborting association:%p\n",
1763 				 __func__, asoc);
1764 
1765 			sctp_primitive_ABORT(net, asoc, chunk);
1766 			err = 0;
1767 			goto out_unlock;
1768 		}
1769 	}
1770 
1771 	/* Do we need to create the association?  */
1772 	if (!asoc) {
1773 		pr_debug("%s: there is no association yet\n", __func__);
1774 
1775 		if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) {
1776 			err = -EINVAL;
1777 			goto out_unlock;
1778 		}
1779 
1780 		/* Check for invalid stream against the stream counts,
1781 		 * either the default or the user specified stream counts.
1782 		 */
1783 		if (sinfo) {
1784 			if (!sinit || !sinit->sinit_num_ostreams) {
1785 				/* Check against the defaults. */
1786 				if (sinfo->sinfo_stream >=
1787 				    sp->initmsg.sinit_num_ostreams) {
1788 					err = -EINVAL;
1789 					goto out_unlock;
1790 				}
1791 			} else {
1792 				/* Check against the requested.  */
1793 				if (sinfo->sinfo_stream >=
1794 				    sinit->sinit_num_ostreams) {
1795 					err = -EINVAL;
1796 					goto out_unlock;
1797 				}
1798 			}
1799 		}
1800 
1801 		/*
1802 		 * API 3.1.2 bind() - UDP Style Syntax
1803 		 * If a bind() or sctp_bindx() is not called prior to a
1804 		 * sendmsg() call that initiates a new association, the
1805 		 * system picks an ephemeral port and will choose an address
1806 		 * set equivalent to binding with a wildcard address.
1807 		 */
1808 		if (!ep->base.bind_addr.port) {
1809 			if (sctp_autobind(sk)) {
1810 				err = -EAGAIN;
1811 				goto out_unlock;
1812 			}
1813 		} else {
1814 			/*
1815 			 * If an unprivileged user inherits a one-to-many
1816 			 * style socket with open associations on a privileged
1817 			 * port, it MAY be permitted to accept new associations,
1818 			 * but it SHOULD NOT be permitted to open new
1819 			 * associations.
1820 			 */
1821 			if (ep->base.bind_addr.port < PROT_SOCK &&
1822 			    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) {
1823 				err = -EACCES;
1824 				goto out_unlock;
1825 			}
1826 		}
1827 
1828 		scope = sctp_scope(&to);
1829 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1830 		if (!new_asoc) {
1831 			err = -ENOMEM;
1832 			goto out_unlock;
1833 		}
1834 		asoc = new_asoc;
1835 		err = sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL);
1836 		if (err < 0) {
1837 			err = -ENOMEM;
1838 			goto out_free;
1839 		}
1840 
1841 		/* If the SCTP_INIT ancillary data is specified, set all
1842 		 * the association init values accordingly.
1843 		 */
1844 		if (sinit) {
1845 			if (sinit->sinit_num_ostreams) {
1846 				asoc->c.sinit_num_ostreams =
1847 					sinit->sinit_num_ostreams;
1848 			}
1849 			if (sinit->sinit_max_instreams) {
1850 				asoc->c.sinit_max_instreams =
1851 					sinit->sinit_max_instreams;
1852 			}
1853 			if (sinit->sinit_max_attempts) {
1854 				asoc->max_init_attempts
1855 					= sinit->sinit_max_attempts;
1856 			}
1857 			if (sinit->sinit_max_init_timeo) {
1858 				asoc->max_init_timeo =
1859 				 msecs_to_jiffies(sinit->sinit_max_init_timeo);
1860 			}
1861 		}
1862 
1863 		/* Prime the peer's transport structures.  */
1864 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN);
1865 		if (!transport) {
1866 			err = -ENOMEM;
1867 			goto out_free;
1868 		}
1869 	}
1870 
1871 	/* ASSERT: we have a valid association at this point.  */
1872 	pr_debug("%s: we have a valid association\n", __func__);
1873 
1874 	if (!sinfo) {
1875 		/* If the user didn't specify SNDINFO/SNDRCVINFO, make up
1876 		 * one with some defaults.
1877 		 */
1878 		memset(&default_sinfo, 0, sizeof(default_sinfo));
1879 		default_sinfo.sinfo_stream = asoc->default_stream;
1880 		default_sinfo.sinfo_flags = asoc->default_flags;
1881 		default_sinfo.sinfo_ppid = asoc->default_ppid;
1882 		default_sinfo.sinfo_context = asoc->default_context;
1883 		default_sinfo.sinfo_timetolive = asoc->default_timetolive;
1884 		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
1885 
1886 		sinfo = &default_sinfo;
1887 	} else if (fill_sinfo_ttl) {
1888 		/* In case SNDINFO was specified, we still need to fill
1889 		 * it with a default ttl from the assoc here.
1890 		 */
1891 		sinfo->sinfo_timetolive = asoc->default_timetolive;
1892 	}
1893 
1894 	/* API 7.1.7, the sndbuf size per association bounds the
1895 	 * maximum size of data that can be sent in a single send call.
1896 	 */
1897 	if (msg_len > sk->sk_sndbuf) {
1898 		err = -EMSGSIZE;
1899 		goto out_free;
1900 	}
1901 
1902 	if (asoc->pmtu_pending)
1903 		sctp_assoc_pending_pmtu(sk, asoc);
1904 
1905 	/* If fragmentation is disabled and the message length exceeds the
1906 	 * association fragmentation point, return EMSGSIZE.  The I-D
1907 	 * does not specify what this error is, but this looks like
1908 	 * a great fit.
1909 	 */
1910 	if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
1911 		err = -EMSGSIZE;
1912 		goto out_free;
1913 	}
1914 
1915 	/* Check for invalid stream. */
1916 	if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) {
1917 		err = -EINVAL;
1918 		goto out_free;
1919 	}
1920 
1921 	if (sctp_wspace(asoc) < msg_len)
1922 		sctp_prsctp_prune(asoc, sinfo, msg_len - sctp_wspace(asoc));
1923 
1924 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1925 	if (!sctp_wspace(asoc)) {
1926 		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
1927 		if (err)
1928 			goto out_free;
1929 	}
1930 
1931 	/* If an address is passed with the sendto/sendmsg call, it is used
1932 	 * to override the primary destination address in the TCP model, or
1933 	 * when SCTP_ADDR_OVER flag is set in the UDP model.
1934 	 */
1935 	if ((sctp_style(sk, TCP) && msg_name) ||
1936 	    (sinfo_flags & SCTP_ADDR_OVER)) {
1937 		chunk_tp = sctp_assoc_lookup_paddr(asoc, &to);
1938 		if (!chunk_tp) {
1939 			err = -EINVAL;
1940 			goto out_free;
1941 		}
1942 	} else
1943 		chunk_tp = NULL;
1944 
1945 	/* Auto-connect, if we aren't connected already. */
1946 	if (sctp_state(asoc, CLOSED)) {
1947 		err = sctp_primitive_ASSOCIATE(net, asoc, NULL);
1948 		if (err < 0)
1949 			goto out_free;
1950 
1951 		wait_connect = true;
1952 		pr_debug("%s: we associated primitively\n", __func__);
1953 	}
1954 
1955 	/* Break the message into multiple chunks of maximum size. */
1956 	datamsg = sctp_datamsg_from_user(asoc, sinfo, &msg->msg_iter);
1957 	if (IS_ERR(datamsg)) {
1958 		err = PTR_ERR(datamsg);
1959 		goto out_free;
1960 	}
1961 
1962 	/* Now send the (possibly) fragmented message. */
1963 	list_for_each_entry(chunk, &datamsg->chunks, frag_list) {
1964 		sctp_chunk_hold(chunk);
1965 
1966 		/* Do accounting for the write space.  */
1967 		sctp_set_owner_w(chunk);
1968 
1969 		chunk->transport = chunk_tp;
1970 	}
1971 
1972 	/* Send it to the lower layers.  Note:  all chunks
1973 	 * must either fail or succeed.   The lower layer
1974 	 * works that way today.  Keep it that way or this
1975 	 * breaks.
1976 	 */
1977 	err = sctp_primitive_SEND(net, asoc, datamsg);
1978 	/* Did the lower layer accept the chunk? */
1979 	if (err) {
1980 		sctp_datamsg_free(datamsg);
1981 		goto out_free;
1982 	}
1983 
1984 	pr_debug("%s: we sent primitively\n", __func__);
1985 
1986 	sctp_datamsg_put(datamsg);
1987 	err = msg_len;
1988 
1989 	if (unlikely(wait_connect)) {
1990 		timeo = sock_sndtimeo(sk, msg_flags & MSG_DONTWAIT);
1991 		sctp_wait_for_connect(asoc, &timeo);
1992 	}
1993 
1994 	/* If we are already past ASSOCIATE, the lower
1995 	 * layers are responsible for association cleanup.
1996 	 */
1997 	goto out_unlock;
1998 
1999 out_free:
2000 	if (new_asoc)
2001 		sctp_association_free(asoc);
2002 out_unlock:
2003 	release_sock(sk);
2004 
2005 out_nounlock:
2006 	return sctp_error(sk, msg_flags, err);
2007 
2008 #if 0
2009 do_sock_err:
2010 	if (msg_len)
2011 		err = msg_len;
2012 	else
2013 		err = sock_error(sk);
2014 	goto out;
2015 
2016 do_interrupted:
2017 	if (msg_len)
2018 		err = msg_len;
2019 	goto out;
2020 #endif /* 0 */
2021 }
2022 
2023 /* This is an extended version of skb_pull() that removes the data from the
2024  * start of a skb even when data is spread across the list of skb's in the
2025  * frag_list. len specifies the total amount of data that needs to be removed.
2026  * when 'len' bytes could be removed from the skb, it returns 0.
2027  * If 'len' exceeds the total skb length,  it returns the no. of bytes that
2028  * could not be removed.
2029  */
2030 static int sctp_skb_pull(struct sk_buff *skb, int len)
2031 {
2032 	struct sk_buff *list;
2033 	int skb_len = skb_headlen(skb);
2034 	int rlen;
2035 
2036 	if (len <= skb_len) {
2037 		__skb_pull(skb, len);
2038 		return 0;
2039 	}
2040 	len -= skb_len;
2041 	__skb_pull(skb, skb_len);
2042 
2043 	skb_walk_frags(skb, list) {
2044 		rlen = sctp_skb_pull(list, len);
2045 		skb->len -= (len-rlen);
2046 		skb->data_len -= (len-rlen);
2047 
2048 		if (!rlen)
2049 			return 0;
2050 
2051 		len = rlen;
2052 	}
2053 
2054 	return len;
2055 }
2056 
2057 /* API 3.1.3  recvmsg() - UDP Style Syntax
2058  *
2059  *  ssize_t recvmsg(int socket, struct msghdr *message,
2060  *                    int flags);
2061  *
2062  *  socket  - the socket descriptor of the endpoint.
2063  *  message - pointer to the msghdr structure which contains a single
2064  *            user message and possibly some ancillary data.
2065  *
2066  *            See Section 5 for complete description of the data
2067  *            structures.
2068  *
2069  *  flags   - flags sent or received with the user message, see Section
2070  *            5 for complete description of the flags.
2071  */
2072 static int sctp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
2073 			int noblock, int flags, int *addr_len)
2074 {
2075 	struct sctp_ulpevent *event = NULL;
2076 	struct sctp_sock *sp = sctp_sk(sk);
2077 	struct sk_buff *skb, *head_skb;
2078 	int copied;
2079 	int err = 0;
2080 	int skb_len;
2081 
2082 	pr_debug("%s: sk:%p, msghdr:%p, len:%zd, noblock:%d, flags:0x%x, "
2083 		 "addr_len:%p)\n", __func__, sk, msg, len, noblock, flags,
2084 		 addr_len);
2085 
2086 	lock_sock(sk);
2087 
2088 	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED) &&
2089 	    !sctp_sstate(sk, CLOSING) && !sctp_sstate(sk, CLOSED)) {
2090 		err = -ENOTCONN;
2091 		goto out;
2092 	}
2093 
2094 	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
2095 	if (!skb)
2096 		goto out;
2097 
2098 	/* Get the total length of the skb including any skb's in the
2099 	 * frag_list.
2100 	 */
2101 	skb_len = skb->len;
2102 
2103 	copied = skb_len;
2104 	if (copied > len)
2105 		copied = len;
2106 
2107 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
2108 
2109 	event = sctp_skb2event(skb);
2110 
2111 	if (err)
2112 		goto out_free;
2113 
2114 	if (event->chunk && event->chunk->head_skb)
2115 		head_skb = event->chunk->head_skb;
2116 	else
2117 		head_skb = skb;
2118 	sock_recv_ts_and_drops(msg, sk, head_skb);
2119 	if (sctp_ulpevent_is_notification(event)) {
2120 		msg->msg_flags |= MSG_NOTIFICATION;
2121 		sp->pf->event_msgname(event, msg->msg_name, addr_len);
2122 	} else {
2123 		sp->pf->skb_msgname(head_skb, msg->msg_name, addr_len);
2124 	}
2125 
2126 	/* Check if we allow SCTP_NXTINFO. */
2127 	if (sp->recvnxtinfo)
2128 		sctp_ulpevent_read_nxtinfo(event, msg, sk);
2129 	/* Check if we allow SCTP_RCVINFO. */
2130 	if (sp->recvrcvinfo)
2131 		sctp_ulpevent_read_rcvinfo(event, msg);
2132 	/* Check if we allow SCTP_SNDRCVINFO. */
2133 	if (sp->subscribe.sctp_data_io_event)
2134 		sctp_ulpevent_read_sndrcvinfo(event, msg);
2135 
2136 	err = copied;
2137 
2138 	/* If skb's length exceeds the user's buffer, update the skb and
2139 	 * push it back to the receive_queue so that the next call to
2140 	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
2141 	 */
2142 	if (skb_len > copied) {
2143 		msg->msg_flags &= ~MSG_EOR;
2144 		if (flags & MSG_PEEK)
2145 			goto out_free;
2146 		sctp_skb_pull(skb, copied);
2147 		skb_queue_head(&sk->sk_receive_queue, skb);
2148 
2149 		/* When only partial message is copied to the user, increase
2150 		 * rwnd by that amount. If all the data in the skb is read,
2151 		 * rwnd is updated when the event is freed.
2152 		 */
2153 		if (!sctp_ulpevent_is_notification(event))
2154 			sctp_assoc_rwnd_increase(event->asoc, copied);
2155 		goto out;
2156 	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
2157 		   (event->msg_flags & MSG_EOR))
2158 		msg->msg_flags |= MSG_EOR;
2159 	else
2160 		msg->msg_flags &= ~MSG_EOR;
2161 
2162 out_free:
2163 	if (flags & MSG_PEEK) {
2164 		/* Release the skb reference acquired after peeking the skb in
2165 		 * sctp_skb_recv_datagram().
2166 		 */
2167 		kfree_skb(skb);
2168 	} else {
2169 		/* Free the event which includes releasing the reference to
2170 		 * the owner of the skb, freeing the skb and updating the
2171 		 * rwnd.
2172 		 */
2173 		sctp_ulpevent_free(event);
2174 	}
2175 out:
2176 	release_sock(sk);
2177 	return err;
2178 }
2179 
2180 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
2181  *
2182  * This option is a on/off flag.  If enabled no SCTP message
2183  * fragmentation will be performed.  Instead if a message being sent
2184  * exceeds the current PMTU size, the message will NOT be sent and
2185  * instead a error will be indicated to the user.
2186  */
2187 static int sctp_setsockopt_disable_fragments(struct sock *sk,
2188 					     char __user *optval,
2189 					     unsigned int optlen)
2190 {
2191 	int val;
2192 
2193 	if (optlen < sizeof(int))
2194 		return -EINVAL;
2195 
2196 	if (get_user(val, (int __user *)optval))
2197 		return -EFAULT;
2198 
2199 	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
2200 
2201 	return 0;
2202 }
2203 
2204 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
2205 				  unsigned int optlen)
2206 {
2207 	struct sctp_association *asoc;
2208 	struct sctp_ulpevent *event;
2209 
2210 	if (optlen > sizeof(struct sctp_event_subscribe))
2211 		return -EINVAL;
2212 	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
2213 		return -EFAULT;
2214 
2215 	/* At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT,
2216 	 * if there is no data to be sent or retransmit, the stack will
2217 	 * immediately send up this notification.
2218 	 */
2219 	if (sctp_ulpevent_type_enabled(SCTP_SENDER_DRY_EVENT,
2220 				       &sctp_sk(sk)->subscribe)) {
2221 		asoc = sctp_id2assoc(sk, 0);
2222 
2223 		if (asoc && sctp_outq_is_empty(&asoc->outqueue)) {
2224 			event = sctp_ulpevent_make_sender_dry_event(asoc,
2225 					GFP_ATOMIC);
2226 			if (!event)
2227 				return -ENOMEM;
2228 
2229 			sctp_ulpq_tail_event(&asoc->ulpq, event);
2230 		}
2231 	}
2232 
2233 	return 0;
2234 }
2235 
2236 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
2237  *
2238  * This socket option is applicable to the UDP-style socket only.  When
2239  * set it will cause associations that are idle for more than the
2240  * specified number of seconds to automatically close.  An association
2241  * being idle is defined an association that has NOT sent or received
2242  * user data.  The special value of '0' indicates that no automatic
2243  * close of any associations should be performed.  The option expects an
2244  * integer defining the number of seconds of idle time before an
2245  * association is closed.
2246  */
2247 static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
2248 				     unsigned int optlen)
2249 {
2250 	struct sctp_sock *sp = sctp_sk(sk);
2251 	struct net *net = sock_net(sk);
2252 
2253 	/* Applicable to UDP-style socket only */
2254 	if (sctp_style(sk, TCP))
2255 		return -EOPNOTSUPP;
2256 	if (optlen != sizeof(int))
2257 		return -EINVAL;
2258 	if (copy_from_user(&sp->autoclose, optval, optlen))
2259 		return -EFAULT;
2260 
2261 	if (sp->autoclose > net->sctp.max_autoclose)
2262 		sp->autoclose = net->sctp.max_autoclose;
2263 
2264 	return 0;
2265 }
2266 
2267 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
2268  *
2269  * Applications can enable or disable heartbeats for any peer address of
2270  * an association, modify an address's heartbeat interval, force a
2271  * heartbeat to be sent immediately, and adjust the address's maximum
2272  * number of retransmissions sent before an address is considered
2273  * unreachable.  The following structure is used to access and modify an
2274  * address's parameters:
2275  *
2276  *  struct sctp_paddrparams {
2277  *     sctp_assoc_t            spp_assoc_id;
2278  *     struct sockaddr_storage spp_address;
2279  *     uint32_t                spp_hbinterval;
2280  *     uint16_t                spp_pathmaxrxt;
2281  *     uint32_t                spp_pathmtu;
2282  *     uint32_t                spp_sackdelay;
2283  *     uint32_t                spp_flags;
2284  * };
2285  *
2286  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
2287  *                     application, and identifies the association for
2288  *                     this query.
2289  *   spp_address     - This specifies which address is of interest.
2290  *   spp_hbinterval  - This contains the value of the heartbeat interval,
2291  *                     in milliseconds.  If a  value of zero
2292  *                     is present in this field then no changes are to
2293  *                     be made to this parameter.
2294  *   spp_pathmaxrxt  - This contains the maximum number of
2295  *                     retransmissions before this address shall be
2296  *                     considered unreachable. If a  value of zero
2297  *                     is present in this field then no changes are to
2298  *                     be made to this parameter.
2299  *   spp_pathmtu     - When Path MTU discovery is disabled the value
2300  *                     specified here will be the "fixed" path mtu.
2301  *                     Note that if the spp_address field is empty
2302  *                     then all associations on this address will
2303  *                     have this fixed path mtu set upon them.
2304  *
2305  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
2306  *                     the number of milliseconds that sacks will be delayed
2307  *                     for. This value will apply to all addresses of an
2308  *                     association if the spp_address field is empty. Note
2309  *                     also, that if delayed sack is enabled and this
2310  *                     value is set to 0, no change is made to the last
2311  *                     recorded delayed sack timer value.
2312  *
2313  *   spp_flags       - These flags are used to control various features
2314  *                     on an association. The flag field may contain
2315  *                     zero or more of the following options.
2316  *
2317  *                     SPP_HB_ENABLE  - Enable heartbeats on the
2318  *                     specified address. Note that if the address
2319  *                     field is empty all addresses for the association
2320  *                     have heartbeats enabled upon them.
2321  *
2322  *                     SPP_HB_DISABLE - Disable heartbeats on the
2323  *                     speicifed address. Note that if the address
2324  *                     field is empty all addresses for the association
2325  *                     will have their heartbeats disabled. Note also
2326  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
2327  *                     mutually exclusive, only one of these two should
2328  *                     be specified. Enabling both fields will have
2329  *                     undetermined results.
2330  *
2331  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
2332  *                     to be made immediately.
2333  *
2334  *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
2335  *                     heartbeat delayis to be set to the value of 0
2336  *                     milliseconds.
2337  *
2338  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
2339  *                     discovery upon the specified address. Note that
2340  *                     if the address feild is empty then all addresses
2341  *                     on the association are effected.
2342  *
2343  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
2344  *                     discovery upon the specified address. Note that
2345  *                     if the address feild is empty then all addresses
2346  *                     on the association are effected. Not also that
2347  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
2348  *                     exclusive. Enabling both will have undetermined
2349  *                     results.
2350  *
2351  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
2352  *                     on delayed sack. The time specified in spp_sackdelay
2353  *                     is used to specify the sack delay for this address. Note
2354  *                     that if spp_address is empty then all addresses will
2355  *                     enable delayed sack and take on the sack delay
2356  *                     value specified in spp_sackdelay.
2357  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
2358  *                     off delayed sack. If the spp_address field is blank then
2359  *                     delayed sack is disabled for the entire association. Note
2360  *                     also that this field is mutually exclusive to
2361  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
2362  *                     results.
2363  */
2364 static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
2365 				       struct sctp_transport   *trans,
2366 				       struct sctp_association *asoc,
2367 				       struct sctp_sock        *sp,
2368 				       int                      hb_change,
2369 				       int                      pmtud_change,
2370 				       int                      sackdelay_change)
2371 {
2372 	int error;
2373 
2374 	if (params->spp_flags & SPP_HB_DEMAND && trans) {
2375 		struct net *net = sock_net(trans->asoc->base.sk);
2376 
2377 		error = sctp_primitive_REQUESTHEARTBEAT(net, trans->asoc, trans);
2378 		if (error)
2379 			return error;
2380 	}
2381 
2382 	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
2383 	 * this field is ignored.  Note also that a value of zero indicates
2384 	 * the current setting should be left unchanged.
2385 	 */
2386 	if (params->spp_flags & SPP_HB_ENABLE) {
2387 
2388 		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
2389 		 * set.  This lets us use 0 value when this flag
2390 		 * is set.
2391 		 */
2392 		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
2393 			params->spp_hbinterval = 0;
2394 
2395 		if (params->spp_hbinterval ||
2396 		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
2397 			if (trans) {
2398 				trans->hbinterval =
2399 				    msecs_to_jiffies(params->spp_hbinterval);
2400 			} else if (asoc) {
2401 				asoc->hbinterval =
2402 				    msecs_to_jiffies(params->spp_hbinterval);
2403 			} else {
2404 				sp->hbinterval = params->spp_hbinterval;
2405 			}
2406 		}
2407 	}
2408 
2409 	if (hb_change) {
2410 		if (trans) {
2411 			trans->param_flags =
2412 				(trans->param_flags & ~SPP_HB) | hb_change;
2413 		} else if (asoc) {
2414 			asoc->param_flags =
2415 				(asoc->param_flags & ~SPP_HB) | hb_change;
2416 		} else {
2417 			sp->param_flags =
2418 				(sp->param_flags & ~SPP_HB) | hb_change;
2419 		}
2420 	}
2421 
2422 	/* When Path MTU discovery is disabled the value specified here will
2423 	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
2424 	 * include the flag SPP_PMTUD_DISABLE for this field to have any
2425 	 * effect).
2426 	 */
2427 	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
2428 		if (trans) {
2429 			trans->pathmtu = params->spp_pathmtu;
2430 			sctp_assoc_sync_pmtu(sctp_opt2sk(sp), asoc);
2431 		} else if (asoc) {
2432 			asoc->pathmtu = params->spp_pathmtu;
2433 			sctp_frag_point(asoc, params->spp_pathmtu);
2434 		} else {
2435 			sp->pathmtu = params->spp_pathmtu;
2436 		}
2437 	}
2438 
2439 	if (pmtud_change) {
2440 		if (trans) {
2441 			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
2442 				(params->spp_flags & SPP_PMTUD_ENABLE);
2443 			trans->param_flags =
2444 				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
2445 			if (update) {
2446 				sctp_transport_pmtu(trans, sctp_opt2sk(sp));
2447 				sctp_assoc_sync_pmtu(sctp_opt2sk(sp), asoc);
2448 			}
2449 		} else if (asoc) {
2450 			asoc->param_flags =
2451 				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
2452 		} else {
2453 			sp->param_flags =
2454 				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
2455 		}
2456 	}
2457 
2458 	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
2459 	 * value of this field is ignored.  Note also that a value of zero
2460 	 * indicates the current setting should be left unchanged.
2461 	 */
2462 	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
2463 		if (trans) {
2464 			trans->sackdelay =
2465 				msecs_to_jiffies(params->spp_sackdelay);
2466 		} else if (asoc) {
2467 			asoc->sackdelay =
2468 				msecs_to_jiffies(params->spp_sackdelay);
2469 		} else {
2470 			sp->sackdelay = params->spp_sackdelay;
2471 		}
2472 	}
2473 
2474 	if (sackdelay_change) {
2475 		if (trans) {
2476 			trans->param_flags =
2477 				(trans->param_flags & ~SPP_SACKDELAY) |
2478 				sackdelay_change;
2479 		} else if (asoc) {
2480 			asoc->param_flags =
2481 				(asoc->param_flags & ~SPP_SACKDELAY) |
2482 				sackdelay_change;
2483 		} else {
2484 			sp->param_flags =
2485 				(sp->param_flags & ~SPP_SACKDELAY) |
2486 				sackdelay_change;
2487 		}
2488 	}
2489 
2490 	/* Note that a value of zero indicates the current setting should be
2491 	   left unchanged.
2492 	 */
2493 	if (params->spp_pathmaxrxt) {
2494 		if (trans) {
2495 			trans->pathmaxrxt = params->spp_pathmaxrxt;
2496 		} else if (asoc) {
2497 			asoc->pathmaxrxt = params->spp_pathmaxrxt;
2498 		} else {
2499 			sp->pathmaxrxt = params->spp_pathmaxrxt;
2500 		}
2501 	}
2502 
2503 	return 0;
2504 }
2505 
2506 static int sctp_setsockopt_peer_addr_params(struct sock *sk,
2507 					    char __user *optval,
2508 					    unsigned int optlen)
2509 {
2510 	struct sctp_paddrparams  params;
2511 	struct sctp_transport   *trans = NULL;
2512 	struct sctp_association *asoc = NULL;
2513 	struct sctp_sock        *sp = sctp_sk(sk);
2514 	int error;
2515 	int hb_change, pmtud_change, sackdelay_change;
2516 
2517 	if (optlen != sizeof(struct sctp_paddrparams))
2518 		return -EINVAL;
2519 
2520 	if (copy_from_user(&params, optval, optlen))
2521 		return -EFAULT;
2522 
2523 	/* Validate flags and value parameters. */
2524 	hb_change        = params.spp_flags & SPP_HB;
2525 	pmtud_change     = params.spp_flags & SPP_PMTUD;
2526 	sackdelay_change = params.spp_flags & SPP_SACKDELAY;
2527 
2528 	if (hb_change        == SPP_HB ||
2529 	    pmtud_change     == SPP_PMTUD ||
2530 	    sackdelay_change == SPP_SACKDELAY ||
2531 	    params.spp_sackdelay > 500 ||
2532 	    (params.spp_pathmtu &&
2533 	     params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
2534 		return -EINVAL;
2535 
2536 	/* If an address other than INADDR_ANY is specified, and
2537 	 * no transport is found, then the request is invalid.
2538 	 */
2539 	if (!sctp_is_any(sk, (union sctp_addr *)&params.spp_address)) {
2540 		trans = sctp_addr_id2transport(sk, &params.spp_address,
2541 					       params.spp_assoc_id);
2542 		if (!trans)
2543 			return -EINVAL;
2544 	}
2545 
2546 	/* Get association, if assoc_id != 0 and the socket is a one
2547 	 * to many style socket, and an association was not found, then
2548 	 * the id was invalid.
2549 	 */
2550 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
2551 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
2552 		return -EINVAL;
2553 
2554 	/* Heartbeat demand can only be sent on a transport or
2555 	 * association, but not a socket.
2556 	 */
2557 	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
2558 		return -EINVAL;
2559 
2560 	/* Process parameters. */
2561 	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2562 					    hb_change, pmtud_change,
2563 					    sackdelay_change);
2564 
2565 	if (error)
2566 		return error;
2567 
2568 	/* If changes are for association, also apply parameters to each
2569 	 * transport.
2570 	 */
2571 	if (!trans && asoc) {
2572 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2573 				transports) {
2574 			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2575 						    hb_change, pmtud_change,
2576 						    sackdelay_change);
2577 		}
2578 	}
2579 
2580 	return 0;
2581 }
2582 
2583 static inline __u32 sctp_spp_sackdelay_enable(__u32 param_flags)
2584 {
2585 	return (param_flags & ~SPP_SACKDELAY) | SPP_SACKDELAY_ENABLE;
2586 }
2587 
2588 static inline __u32 sctp_spp_sackdelay_disable(__u32 param_flags)
2589 {
2590 	return (param_flags & ~SPP_SACKDELAY) | SPP_SACKDELAY_DISABLE;
2591 }
2592 
2593 /*
2594  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
2595  *
2596  * This option will effect the way delayed acks are performed.  This
2597  * option allows you to get or set the delayed ack time, in
2598  * milliseconds.  It also allows changing the delayed ack frequency.
2599  * Changing the frequency to 1 disables the delayed sack algorithm.  If
2600  * the assoc_id is 0, then this sets or gets the endpoints default
2601  * values.  If the assoc_id field is non-zero, then the set or get
2602  * effects the specified association for the one to many model (the
2603  * assoc_id field is ignored by the one to one model).  Note that if
2604  * sack_delay or sack_freq are 0 when setting this option, then the
2605  * current values will remain unchanged.
2606  *
2607  * struct sctp_sack_info {
2608  *     sctp_assoc_t            sack_assoc_id;
2609  *     uint32_t                sack_delay;
2610  *     uint32_t                sack_freq;
2611  * };
2612  *
2613  * sack_assoc_id -  This parameter, indicates which association the user
2614  *    is performing an action upon.  Note that if this field's value is
2615  *    zero then the endpoints default value is changed (effecting future
2616  *    associations only).
2617  *
2618  * sack_delay -  This parameter contains the number of milliseconds that
2619  *    the user is requesting the delayed ACK timer be set to.  Note that
2620  *    this value is defined in the standard to be between 200 and 500
2621  *    milliseconds.
2622  *
2623  * sack_freq -  This parameter contains the number of packets that must
2624  *    be received before a sack is sent without waiting for the delay
2625  *    timer to expire.  The default value for this is 2, setting this
2626  *    value to 1 will disable the delayed sack algorithm.
2627  */
2628 
2629 static int sctp_setsockopt_delayed_ack(struct sock *sk,
2630 				       char __user *optval, unsigned int optlen)
2631 {
2632 	struct sctp_sack_info    params;
2633 	struct sctp_transport   *trans = NULL;
2634 	struct sctp_association *asoc = NULL;
2635 	struct sctp_sock        *sp = sctp_sk(sk);
2636 
2637 	if (optlen == sizeof(struct sctp_sack_info)) {
2638 		if (copy_from_user(&params, optval, optlen))
2639 			return -EFAULT;
2640 
2641 		if (params.sack_delay == 0 && params.sack_freq == 0)
2642 			return 0;
2643 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
2644 		pr_warn_ratelimited(DEPRECATED
2645 				    "%s (pid %d) "
2646 				    "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
2647 				    "Use struct sctp_sack_info instead\n",
2648 				    current->comm, task_pid_nr(current));
2649 		if (copy_from_user(&params, optval, optlen))
2650 			return -EFAULT;
2651 
2652 		if (params.sack_delay == 0)
2653 			params.sack_freq = 1;
2654 		else
2655 			params.sack_freq = 0;
2656 	} else
2657 		return -EINVAL;
2658 
2659 	/* Validate value parameter. */
2660 	if (params.sack_delay > 500)
2661 		return -EINVAL;
2662 
2663 	/* Get association, if sack_assoc_id != 0 and the socket is a one
2664 	 * to many style socket, and an association was not found, then
2665 	 * the id was invalid.
2666 	 */
2667 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
2668 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
2669 		return -EINVAL;
2670 
2671 	if (params.sack_delay) {
2672 		if (asoc) {
2673 			asoc->sackdelay =
2674 				msecs_to_jiffies(params.sack_delay);
2675 			asoc->param_flags =
2676 				sctp_spp_sackdelay_enable(asoc->param_flags);
2677 		} else {
2678 			sp->sackdelay = params.sack_delay;
2679 			sp->param_flags =
2680 				sctp_spp_sackdelay_enable(sp->param_flags);
2681 		}
2682 	}
2683 
2684 	if (params.sack_freq == 1) {
2685 		if (asoc) {
2686 			asoc->param_flags =
2687 				sctp_spp_sackdelay_disable(asoc->param_flags);
2688 		} else {
2689 			sp->param_flags =
2690 				sctp_spp_sackdelay_disable(sp->param_flags);
2691 		}
2692 	} else if (params.sack_freq > 1) {
2693 		if (asoc) {
2694 			asoc->sackfreq = params.sack_freq;
2695 			asoc->param_flags =
2696 				sctp_spp_sackdelay_enable(asoc->param_flags);
2697 		} else {
2698 			sp->sackfreq = params.sack_freq;
2699 			sp->param_flags =
2700 				sctp_spp_sackdelay_enable(sp->param_flags);
2701 		}
2702 	}
2703 
2704 	/* If change is for association, also apply to each transport. */
2705 	if (asoc) {
2706 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2707 				transports) {
2708 			if (params.sack_delay) {
2709 				trans->sackdelay =
2710 					msecs_to_jiffies(params.sack_delay);
2711 				trans->param_flags =
2712 					sctp_spp_sackdelay_enable(trans->param_flags);
2713 			}
2714 			if (params.sack_freq == 1) {
2715 				trans->param_flags =
2716 					sctp_spp_sackdelay_disable(trans->param_flags);
2717 			} else if (params.sack_freq > 1) {
2718 				trans->sackfreq = params.sack_freq;
2719 				trans->param_flags =
2720 					sctp_spp_sackdelay_enable(trans->param_flags);
2721 			}
2722 		}
2723 	}
2724 
2725 	return 0;
2726 }
2727 
2728 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
2729  *
2730  * Applications can specify protocol parameters for the default association
2731  * initialization.  The option name argument to setsockopt() and getsockopt()
2732  * is SCTP_INITMSG.
2733  *
2734  * Setting initialization parameters is effective only on an unconnected
2735  * socket (for UDP-style sockets only future associations are effected
2736  * by the change).  With TCP-style sockets, this option is inherited by
2737  * sockets derived from a listener socket.
2738  */
2739 static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, unsigned int optlen)
2740 {
2741 	struct sctp_initmsg sinit;
2742 	struct sctp_sock *sp = sctp_sk(sk);
2743 
2744 	if (optlen != sizeof(struct sctp_initmsg))
2745 		return -EINVAL;
2746 	if (copy_from_user(&sinit, optval, optlen))
2747 		return -EFAULT;
2748 
2749 	if (sinit.sinit_num_ostreams)
2750 		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
2751 	if (sinit.sinit_max_instreams)
2752 		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
2753 	if (sinit.sinit_max_attempts)
2754 		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
2755 	if (sinit.sinit_max_init_timeo)
2756 		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
2757 
2758 	return 0;
2759 }
2760 
2761 /*
2762  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
2763  *
2764  *   Applications that wish to use the sendto() system call may wish to
2765  *   specify a default set of parameters that would normally be supplied
2766  *   through the inclusion of ancillary data.  This socket option allows
2767  *   such an application to set the default sctp_sndrcvinfo structure.
2768  *   The application that wishes to use this socket option simply passes
2769  *   in to this call the sctp_sndrcvinfo structure defined in Section
2770  *   5.2.2) The input parameters accepted by this call include
2771  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
2772  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
2773  *   to this call if the caller is using the UDP model.
2774  */
2775 static int sctp_setsockopt_default_send_param(struct sock *sk,
2776 					      char __user *optval,
2777 					      unsigned int optlen)
2778 {
2779 	struct sctp_sock *sp = sctp_sk(sk);
2780 	struct sctp_association *asoc;
2781 	struct sctp_sndrcvinfo info;
2782 
2783 	if (optlen != sizeof(info))
2784 		return -EINVAL;
2785 	if (copy_from_user(&info, optval, optlen))
2786 		return -EFAULT;
2787 	if (info.sinfo_flags &
2788 	    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
2789 	      SCTP_ABORT | SCTP_EOF))
2790 		return -EINVAL;
2791 
2792 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
2793 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
2794 		return -EINVAL;
2795 	if (asoc) {
2796 		asoc->default_stream = info.sinfo_stream;
2797 		asoc->default_flags = info.sinfo_flags;
2798 		asoc->default_ppid = info.sinfo_ppid;
2799 		asoc->default_context = info.sinfo_context;
2800 		asoc->default_timetolive = info.sinfo_timetolive;
2801 	} else {
2802 		sp->default_stream = info.sinfo_stream;
2803 		sp->default_flags = info.sinfo_flags;
2804 		sp->default_ppid = info.sinfo_ppid;
2805 		sp->default_context = info.sinfo_context;
2806 		sp->default_timetolive = info.sinfo_timetolive;
2807 	}
2808 
2809 	return 0;
2810 }
2811 
2812 /* RFC6458, Section 8.1.31. Set/get Default Send Parameters
2813  * (SCTP_DEFAULT_SNDINFO)
2814  */
2815 static int sctp_setsockopt_default_sndinfo(struct sock *sk,
2816 					   char __user *optval,
2817 					   unsigned int optlen)
2818 {
2819 	struct sctp_sock *sp = sctp_sk(sk);
2820 	struct sctp_association *asoc;
2821 	struct sctp_sndinfo info;
2822 
2823 	if (optlen != sizeof(info))
2824 		return -EINVAL;
2825 	if (copy_from_user(&info, optval, optlen))
2826 		return -EFAULT;
2827 	if (info.snd_flags &
2828 	    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
2829 	      SCTP_ABORT | SCTP_EOF))
2830 		return -EINVAL;
2831 
2832 	asoc = sctp_id2assoc(sk, info.snd_assoc_id);
2833 	if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
2834 		return -EINVAL;
2835 	if (asoc) {
2836 		asoc->default_stream = info.snd_sid;
2837 		asoc->default_flags = info.snd_flags;
2838 		asoc->default_ppid = info.snd_ppid;
2839 		asoc->default_context = info.snd_context;
2840 	} else {
2841 		sp->default_stream = info.snd_sid;
2842 		sp->default_flags = info.snd_flags;
2843 		sp->default_ppid = info.snd_ppid;
2844 		sp->default_context = info.snd_context;
2845 	}
2846 
2847 	return 0;
2848 }
2849 
2850 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
2851  *
2852  * Requests that the local SCTP stack use the enclosed peer address as
2853  * the association primary.  The enclosed address must be one of the
2854  * association peer's addresses.
2855  */
2856 static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
2857 					unsigned int optlen)
2858 {
2859 	struct sctp_prim prim;
2860 	struct sctp_transport *trans;
2861 
2862 	if (optlen != sizeof(struct sctp_prim))
2863 		return -EINVAL;
2864 
2865 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
2866 		return -EFAULT;
2867 
2868 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
2869 	if (!trans)
2870 		return -EINVAL;
2871 
2872 	sctp_assoc_set_primary(trans->asoc, trans);
2873 
2874 	return 0;
2875 }
2876 
2877 /*
2878  * 7.1.5 SCTP_NODELAY
2879  *
2880  * Turn on/off any Nagle-like algorithm.  This means that packets are
2881  * generally sent as soon as possible and no unnecessary delays are
2882  * introduced, at the cost of more packets in the network.  Expects an
2883  *  integer boolean flag.
2884  */
2885 static int sctp_setsockopt_nodelay(struct sock *sk, char __user *optval,
2886 				   unsigned int optlen)
2887 {
2888 	int val;
2889 
2890 	if (optlen < sizeof(int))
2891 		return -EINVAL;
2892 	if (get_user(val, (int __user *)optval))
2893 		return -EFAULT;
2894 
2895 	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
2896 	return 0;
2897 }
2898 
2899 /*
2900  *
2901  * 7.1.1 SCTP_RTOINFO
2902  *
2903  * The protocol parameters used to initialize and bound retransmission
2904  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
2905  * and modify these parameters.
2906  * All parameters are time values, in milliseconds.  A value of 0, when
2907  * modifying the parameters, indicates that the current value should not
2908  * be changed.
2909  *
2910  */
2911 static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, unsigned int optlen)
2912 {
2913 	struct sctp_rtoinfo rtoinfo;
2914 	struct sctp_association *asoc;
2915 	unsigned long rto_min, rto_max;
2916 	struct sctp_sock *sp = sctp_sk(sk);
2917 
2918 	if (optlen != sizeof (struct sctp_rtoinfo))
2919 		return -EINVAL;
2920 
2921 	if (copy_from_user(&rtoinfo, optval, optlen))
2922 		return -EFAULT;
2923 
2924 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
2925 
2926 	/* Set the values to the specific association */
2927 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
2928 		return -EINVAL;
2929 
2930 	rto_max = rtoinfo.srto_max;
2931 	rto_min = rtoinfo.srto_min;
2932 
2933 	if (rto_max)
2934 		rto_max = asoc ? msecs_to_jiffies(rto_max) : rto_max;
2935 	else
2936 		rto_max = asoc ? asoc->rto_max : sp->rtoinfo.srto_max;
2937 
2938 	if (rto_min)
2939 		rto_min = asoc ? msecs_to_jiffies(rto_min) : rto_min;
2940 	else
2941 		rto_min = asoc ? asoc->rto_min : sp->rtoinfo.srto_min;
2942 
2943 	if (rto_min > rto_max)
2944 		return -EINVAL;
2945 
2946 	if (asoc) {
2947 		if (rtoinfo.srto_initial != 0)
2948 			asoc->rto_initial =
2949 				msecs_to_jiffies(rtoinfo.srto_initial);
2950 		asoc->rto_max = rto_max;
2951 		asoc->rto_min = rto_min;
2952 	} else {
2953 		/* If there is no association or the association-id = 0
2954 		 * set the values to the endpoint.
2955 		 */
2956 		if (rtoinfo.srto_initial != 0)
2957 			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
2958 		sp->rtoinfo.srto_max = rto_max;
2959 		sp->rtoinfo.srto_min = rto_min;
2960 	}
2961 
2962 	return 0;
2963 }
2964 
2965 /*
2966  *
2967  * 7.1.2 SCTP_ASSOCINFO
2968  *
2969  * This option is used to tune the maximum retransmission attempts
2970  * of the association.
2971  * Returns an error if the new association retransmission value is
2972  * greater than the sum of the retransmission value  of the peer.
2973  * See [SCTP] for more information.
2974  *
2975  */
2976 static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, unsigned int optlen)
2977 {
2978 
2979 	struct sctp_assocparams assocparams;
2980 	struct sctp_association *asoc;
2981 
2982 	if (optlen != sizeof(struct sctp_assocparams))
2983 		return -EINVAL;
2984 	if (copy_from_user(&assocparams, optval, optlen))
2985 		return -EFAULT;
2986 
2987 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
2988 
2989 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
2990 		return -EINVAL;
2991 
2992 	/* Set the values to the specific association */
2993 	if (asoc) {
2994 		if (assocparams.sasoc_asocmaxrxt != 0) {
2995 			__u32 path_sum = 0;
2996 			int   paths = 0;
2997 			struct sctp_transport *peer_addr;
2998 
2999 			list_for_each_entry(peer_addr, &asoc->peer.transport_addr_list,
3000 					transports) {
3001 				path_sum += peer_addr->pathmaxrxt;
3002 				paths++;
3003 			}
3004 
3005 			/* Only validate asocmaxrxt if we have more than
3006 			 * one path/transport.  We do this because path
3007 			 * retransmissions are only counted when we have more
3008 			 * then one path.
3009 			 */
3010 			if (paths > 1 &&
3011 			    assocparams.sasoc_asocmaxrxt > path_sum)
3012 				return -EINVAL;
3013 
3014 			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
3015 		}
3016 
3017 		if (assocparams.sasoc_cookie_life != 0)
3018 			asoc->cookie_life = ms_to_ktime(assocparams.sasoc_cookie_life);
3019 	} else {
3020 		/* Set the values to the endpoint */
3021 		struct sctp_sock *sp = sctp_sk(sk);
3022 
3023 		if (assocparams.sasoc_asocmaxrxt != 0)
3024 			sp->assocparams.sasoc_asocmaxrxt =
3025 						assocparams.sasoc_asocmaxrxt;
3026 		if (assocparams.sasoc_cookie_life != 0)
3027 			sp->assocparams.sasoc_cookie_life =
3028 						assocparams.sasoc_cookie_life;
3029 	}
3030 	return 0;
3031 }
3032 
3033 /*
3034  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
3035  *
3036  * This socket option is a boolean flag which turns on or off mapped V4
3037  * addresses.  If this option is turned on and the socket is type
3038  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
3039  * If this option is turned off, then no mapping will be done of V4
3040  * addresses and a user will receive both PF_INET6 and PF_INET type
3041  * addresses on the socket.
3042  */
3043 static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsigned int optlen)
3044 {
3045 	int val;
3046 	struct sctp_sock *sp = sctp_sk(sk);
3047 
3048 	if (optlen < sizeof(int))
3049 		return -EINVAL;
3050 	if (get_user(val, (int __user *)optval))
3051 		return -EFAULT;
3052 	if (val)
3053 		sp->v4mapped = 1;
3054 	else
3055 		sp->v4mapped = 0;
3056 
3057 	return 0;
3058 }
3059 
3060 /*
3061  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
3062  * This option will get or set the maximum size to put in any outgoing
3063  * SCTP DATA chunk.  If a message is larger than this size it will be
3064  * fragmented by SCTP into the specified size.  Note that the underlying
3065  * SCTP implementation may fragment into smaller sized chunks when the
3066  * PMTU of the underlying association is smaller than the value set by
3067  * the user.  The default value for this option is '0' which indicates
3068  * the user is NOT limiting fragmentation and only the PMTU will effect
3069  * SCTP's choice of DATA chunk size.  Note also that values set larger
3070  * than the maximum size of an IP datagram will effectively let SCTP
3071  * control fragmentation (i.e. the same as setting this option to 0).
3072  *
3073  * The following structure is used to access and modify this parameter:
3074  *
3075  * struct sctp_assoc_value {
3076  *   sctp_assoc_t assoc_id;
3077  *   uint32_t assoc_value;
3078  * };
3079  *
3080  * assoc_id:  This parameter is ignored for one-to-one style sockets.
3081  *    For one-to-many style sockets this parameter indicates which
3082  *    association the user is performing an action upon.  Note that if
3083  *    this field's value is zero then the endpoints default value is
3084  *    changed (effecting future associations only).
3085  * assoc_value:  This parameter specifies the maximum size in bytes.
3086  */
3087 static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
3088 {
3089 	struct sctp_assoc_value params;
3090 	struct sctp_association *asoc;
3091 	struct sctp_sock *sp = sctp_sk(sk);
3092 	int val;
3093 
3094 	if (optlen == sizeof(int)) {
3095 		pr_warn_ratelimited(DEPRECATED
3096 				    "%s (pid %d) "
3097 				    "Use of int in maxseg socket option.\n"
3098 				    "Use struct sctp_assoc_value instead\n",
3099 				    current->comm, task_pid_nr(current));
3100 		if (copy_from_user(&val, optval, optlen))
3101 			return -EFAULT;
3102 		params.assoc_id = 0;
3103 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
3104 		if (copy_from_user(&params, optval, optlen))
3105 			return -EFAULT;
3106 		val = params.assoc_value;
3107 	} else
3108 		return -EINVAL;
3109 
3110 	if ((val != 0) && ((val < 8) || (val > SCTP_MAX_CHUNK_LEN)))
3111 		return -EINVAL;
3112 
3113 	asoc = sctp_id2assoc(sk, params.assoc_id);
3114 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
3115 		return -EINVAL;
3116 
3117 	if (asoc) {
3118 		if (val == 0) {
3119 			val = asoc->pathmtu;
3120 			val -= sp->pf->af->net_header_len;
3121 			val -= sizeof(struct sctphdr) +
3122 					sizeof(struct sctp_data_chunk);
3123 		}
3124 		asoc->user_frag = val;
3125 		asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
3126 	} else {
3127 		sp->user_frag = val;
3128 	}
3129 
3130 	return 0;
3131 }
3132 
3133 
3134 /*
3135  *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
3136  *
3137  *   Requests that the peer mark the enclosed address as the association
3138  *   primary. The enclosed address must be one of the association's
3139  *   locally bound addresses. The following structure is used to make a
3140  *   set primary request:
3141  */
3142 static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
3143 					     unsigned int optlen)
3144 {
3145 	struct net *net = sock_net(sk);
3146 	struct sctp_sock	*sp;
3147 	struct sctp_association	*asoc = NULL;
3148 	struct sctp_setpeerprim	prim;
3149 	struct sctp_chunk	*chunk;
3150 	struct sctp_af		*af;
3151 	int 			err;
3152 
3153 	sp = sctp_sk(sk);
3154 
3155 	if (!net->sctp.addip_enable)
3156 		return -EPERM;
3157 
3158 	if (optlen != sizeof(struct sctp_setpeerprim))
3159 		return -EINVAL;
3160 
3161 	if (copy_from_user(&prim, optval, optlen))
3162 		return -EFAULT;
3163 
3164 	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
3165 	if (!asoc)
3166 		return -EINVAL;
3167 
3168 	if (!asoc->peer.asconf_capable)
3169 		return -EPERM;
3170 
3171 	if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
3172 		return -EPERM;
3173 
3174 	if (!sctp_state(asoc, ESTABLISHED))
3175 		return -ENOTCONN;
3176 
3177 	af = sctp_get_af_specific(prim.sspp_addr.ss_family);
3178 	if (!af)
3179 		return -EINVAL;
3180 
3181 	if (!af->addr_valid((union sctp_addr *)&prim.sspp_addr, sp, NULL))
3182 		return -EADDRNOTAVAIL;
3183 
3184 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
3185 		return -EADDRNOTAVAIL;
3186 
3187 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
3188 	chunk = sctp_make_asconf_set_prim(asoc,
3189 					  (union sctp_addr *)&prim.sspp_addr);
3190 	if (!chunk)
3191 		return -ENOMEM;
3192 
3193 	err = sctp_send_asconf(asoc, chunk);
3194 
3195 	pr_debug("%s: we set peer primary addr primitively\n", __func__);
3196 
3197 	return err;
3198 }
3199 
3200 static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
3201 					    unsigned int optlen)
3202 {
3203 	struct sctp_setadaptation adaptation;
3204 
3205 	if (optlen != sizeof(struct sctp_setadaptation))
3206 		return -EINVAL;
3207 	if (copy_from_user(&adaptation, optval, optlen))
3208 		return -EFAULT;
3209 
3210 	sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
3211 
3212 	return 0;
3213 }
3214 
3215 /*
3216  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
3217  *
3218  * The context field in the sctp_sndrcvinfo structure is normally only
3219  * used when a failed message is retrieved holding the value that was
3220  * sent down on the actual send call.  This option allows the setting of
3221  * a default context on an association basis that will be received on
3222  * reading messages from the peer.  This is especially helpful in the
3223  * one-2-many model for an application to keep some reference to an
3224  * internal state machine that is processing messages on the
3225  * association.  Note that the setting of this value only effects
3226  * received messages from the peer and does not effect the value that is
3227  * saved with outbound messages.
3228  */
3229 static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
3230 				   unsigned int optlen)
3231 {
3232 	struct sctp_assoc_value params;
3233 	struct sctp_sock *sp;
3234 	struct sctp_association *asoc;
3235 
3236 	if (optlen != sizeof(struct sctp_assoc_value))
3237 		return -EINVAL;
3238 	if (copy_from_user(&params, optval, optlen))
3239 		return -EFAULT;
3240 
3241 	sp = sctp_sk(sk);
3242 
3243 	if (params.assoc_id != 0) {
3244 		asoc = sctp_id2assoc(sk, params.assoc_id);
3245 		if (!asoc)
3246 			return -EINVAL;
3247 		asoc->default_rcv_context = params.assoc_value;
3248 	} else {
3249 		sp->default_rcv_context = params.assoc_value;
3250 	}
3251 
3252 	return 0;
3253 }
3254 
3255 /*
3256  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
3257  *
3258  * This options will at a minimum specify if the implementation is doing
3259  * fragmented interleave.  Fragmented interleave, for a one to many
3260  * socket, is when subsequent calls to receive a message may return
3261  * parts of messages from different associations.  Some implementations
3262  * may allow you to turn this value on or off.  If so, when turned off,
3263  * no fragment interleave will occur (which will cause a head of line
3264  * blocking amongst multiple associations sharing the same one to many
3265  * socket).  When this option is turned on, then each receive call may
3266  * come from a different association (thus the user must receive data
3267  * with the extended calls (e.g. sctp_recvmsg) to keep track of which
3268  * association each receive belongs to.
3269  *
3270  * This option takes a boolean value.  A non-zero value indicates that
3271  * fragmented interleave is on.  A value of zero indicates that
3272  * fragmented interleave is off.
3273  *
3274  * Note that it is important that an implementation that allows this
3275  * option to be turned on, have it off by default.  Otherwise an unaware
3276  * application using the one to many model may become confused and act
3277  * incorrectly.
3278  */
3279 static int sctp_setsockopt_fragment_interleave(struct sock *sk,
3280 					       char __user *optval,
3281 					       unsigned int optlen)
3282 {
3283 	int val;
3284 
3285 	if (optlen != sizeof(int))
3286 		return -EINVAL;
3287 	if (get_user(val, (int __user *)optval))
3288 		return -EFAULT;
3289 
3290 	sctp_sk(sk)->frag_interleave = (val == 0) ? 0 : 1;
3291 
3292 	return 0;
3293 }
3294 
3295 /*
3296  * 8.1.21.  Set or Get the SCTP Partial Delivery Point
3297  *       (SCTP_PARTIAL_DELIVERY_POINT)
3298  *
3299  * This option will set or get the SCTP partial delivery point.  This
3300  * point is the size of a message where the partial delivery API will be
3301  * invoked to help free up rwnd space for the peer.  Setting this to a
3302  * lower value will cause partial deliveries to happen more often.  The
3303  * calls argument is an integer that sets or gets the partial delivery
3304  * point.  Note also that the call will fail if the user attempts to set
3305  * this value larger than the socket receive buffer size.
3306  *
3307  * Note that any single message having a length smaller than or equal to
3308  * the SCTP partial delivery point will be delivered in one single read
3309  * call as long as the user provided buffer is large enough to hold the
3310  * message.
3311  */
3312 static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
3313 						  char __user *optval,
3314 						  unsigned int optlen)
3315 {
3316 	u32 val;
3317 
3318 	if (optlen != sizeof(u32))
3319 		return -EINVAL;
3320 	if (get_user(val, (int __user *)optval))
3321 		return -EFAULT;
3322 
3323 	/* Note: We double the receive buffer from what the user sets
3324 	 * it to be, also initial rwnd is based on rcvbuf/2.
3325 	 */
3326 	if (val > (sk->sk_rcvbuf >> 1))
3327 		return -EINVAL;
3328 
3329 	sctp_sk(sk)->pd_point = val;
3330 
3331 	return 0; /* is this the right error code? */
3332 }
3333 
3334 /*
3335  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
3336  *
3337  * This option will allow a user to change the maximum burst of packets
3338  * that can be emitted by this association.  Note that the default value
3339  * is 4, and some implementations may restrict this setting so that it
3340  * can only be lowered.
3341  *
3342  * NOTE: This text doesn't seem right.  Do this on a socket basis with
3343  * future associations inheriting the socket value.
3344  */
3345 static int sctp_setsockopt_maxburst(struct sock *sk,
3346 				    char __user *optval,
3347 				    unsigned int optlen)
3348 {
3349 	struct sctp_assoc_value params;
3350 	struct sctp_sock *sp;
3351 	struct sctp_association *asoc;
3352 	int val;
3353 	int assoc_id = 0;
3354 
3355 	if (optlen == sizeof(int)) {
3356 		pr_warn_ratelimited(DEPRECATED
3357 				    "%s (pid %d) "
3358 				    "Use of int in max_burst socket option deprecated.\n"
3359 				    "Use struct sctp_assoc_value instead\n",
3360 				    current->comm, task_pid_nr(current));
3361 		if (copy_from_user(&val, optval, optlen))
3362 			return -EFAULT;
3363 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
3364 		if (copy_from_user(&params, optval, optlen))
3365 			return -EFAULT;
3366 		val = params.assoc_value;
3367 		assoc_id = params.assoc_id;
3368 	} else
3369 		return -EINVAL;
3370 
3371 	sp = sctp_sk(sk);
3372 
3373 	if (assoc_id != 0) {
3374 		asoc = sctp_id2assoc(sk, assoc_id);
3375 		if (!asoc)
3376 			return -EINVAL;
3377 		asoc->max_burst = val;
3378 	} else
3379 		sp->max_burst = val;
3380 
3381 	return 0;
3382 }
3383 
3384 /*
3385  * 7.1.18.  Add a chunk that must be authenticated (SCTP_AUTH_CHUNK)
3386  *
3387  * This set option adds a chunk type that the user is requesting to be
3388  * received only in an authenticated way.  Changes to the list of chunks
3389  * will only effect future associations on the socket.
3390  */
3391 static int sctp_setsockopt_auth_chunk(struct sock *sk,
3392 				      char __user *optval,
3393 				      unsigned int optlen)
3394 {
3395 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3396 	struct sctp_authchunk val;
3397 
3398 	if (!ep->auth_enable)
3399 		return -EACCES;
3400 
3401 	if (optlen != sizeof(struct sctp_authchunk))
3402 		return -EINVAL;
3403 	if (copy_from_user(&val, optval, optlen))
3404 		return -EFAULT;
3405 
3406 	switch (val.sauth_chunk) {
3407 	case SCTP_CID_INIT:
3408 	case SCTP_CID_INIT_ACK:
3409 	case SCTP_CID_SHUTDOWN_COMPLETE:
3410 	case SCTP_CID_AUTH:
3411 		return -EINVAL;
3412 	}
3413 
3414 	/* add this chunk id to the endpoint */
3415 	return sctp_auth_ep_add_chunkid(ep, val.sauth_chunk);
3416 }
3417 
3418 /*
3419  * 7.1.19.  Get or set the list of supported HMAC Identifiers (SCTP_HMAC_IDENT)
3420  *
3421  * This option gets or sets the list of HMAC algorithms that the local
3422  * endpoint requires the peer to use.
3423  */
3424 static int sctp_setsockopt_hmac_ident(struct sock *sk,
3425 				      char __user *optval,
3426 				      unsigned int optlen)
3427 {
3428 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3429 	struct sctp_hmacalgo *hmacs;
3430 	u32 idents;
3431 	int err;
3432 
3433 	if (!ep->auth_enable)
3434 		return -EACCES;
3435 
3436 	if (optlen < sizeof(struct sctp_hmacalgo))
3437 		return -EINVAL;
3438 
3439 	hmacs = memdup_user(optval, optlen);
3440 	if (IS_ERR(hmacs))
3441 		return PTR_ERR(hmacs);
3442 
3443 	idents = hmacs->shmac_num_idents;
3444 	if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS ||
3445 	    (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo))) {
3446 		err = -EINVAL;
3447 		goto out;
3448 	}
3449 
3450 	err = sctp_auth_ep_set_hmacs(ep, hmacs);
3451 out:
3452 	kfree(hmacs);
3453 	return err;
3454 }
3455 
3456 /*
3457  * 7.1.20.  Set a shared key (SCTP_AUTH_KEY)
3458  *
3459  * This option will set a shared secret key which is used to build an
3460  * association shared key.
3461  */
3462 static int sctp_setsockopt_auth_key(struct sock *sk,
3463 				    char __user *optval,
3464 				    unsigned int optlen)
3465 {
3466 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3467 	struct sctp_authkey *authkey;
3468 	struct sctp_association *asoc;
3469 	int ret;
3470 
3471 	if (!ep->auth_enable)
3472 		return -EACCES;
3473 
3474 	if (optlen <= sizeof(struct sctp_authkey))
3475 		return -EINVAL;
3476 
3477 	authkey = memdup_user(optval, optlen);
3478 	if (IS_ERR(authkey))
3479 		return PTR_ERR(authkey);
3480 
3481 	if (authkey->sca_keylength > optlen - sizeof(struct sctp_authkey)) {
3482 		ret = -EINVAL;
3483 		goto out;
3484 	}
3485 
3486 	asoc = sctp_id2assoc(sk, authkey->sca_assoc_id);
3487 	if (!asoc && authkey->sca_assoc_id && sctp_style(sk, UDP)) {
3488 		ret = -EINVAL;
3489 		goto out;
3490 	}
3491 
3492 	ret = sctp_auth_set_key(ep, asoc, authkey);
3493 out:
3494 	kzfree(authkey);
3495 	return ret;
3496 }
3497 
3498 /*
3499  * 7.1.21.  Get or set the active shared key (SCTP_AUTH_ACTIVE_KEY)
3500  *
3501  * This option will get or set the active shared key to be used to build
3502  * the association shared key.
3503  */
3504 static int sctp_setsockopt_active_key(struct sock *sk,
3505 				      char __user *optval,
3506 				      unsigned int optlen)
3507 {
3508 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3509 	struct sctp_authkeyid val;
3510 	struct sctp_association *asoc;
3511 
3512 	if (!ep->auth_enable)
3513 		return -EACCES;
3514 
3515 	if (optlen != sizeof(struct sctp_authkeyid))
3516 		return -EINVAL;
3517 	if (copy_from_user(&val, optval, optlen))
3518 		return -EFAULT;
3519 
3520 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3521 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3522 		return -EINVAL;
3523 
3524 	return sctp_auth_set_active_key(ep, asoc, val.scact_keynumber);
3525 }
3526 
3527 /*
3528  * 7.1.22.  Delete a shared key (SCTP_AUTH_DELETE_KEY)
3529  *
3530  * This set option will delete a shared secret key from use.
3531  */
3532 static int sctp_setsockopt_del_key(struct sock *sk,
3533 				   char __user *optval,
3534 				   unsigned int optlen)
3535 {
3536 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
3537 	struct sctp_authkeyid val;
3538 	struct sctp_association *asoc;
3539 
3540 	if (!ep->auth_enable)
3541 		return -EACCES;
3542 
3543 	if (optlen != sizeof(struct sctp_authkeyid))
3544 		return -EINVAL;
3545 	if (copy_from_user(&val, optval, optlen))
3546 		return -EFAULT;
3547 
3548 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3549 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3550 		return -EINVAL;
3551 
3552 	return sctp_auth_del_key_id(ep, asoc, val.scact_keynumber);
3553 
3554 }
3555 
3556 /*
3557  * 8.1.23 SCTP_AUTO_ASCONF
3558  *
3559  * This option will enable or disable the use of the automatic generation of
3560  * ASCONF chunks to add and delete addresses to an existing association.  Note
3561  * that this option has two caveats namely: a) it only affects sockets that
3562  * are bound to all addresses available to the SCTP stack, and b) the system
3563  * administrator may have an overriding control that turns the ASCONF feature
3564  * off no matter what setting the socket option may have.
3565  * This option expects an integer boolean flag, where a non-zero value turns on
3566  * the option, and a zero value turns off the option.
3567  * Note. In this implementation, socket operation overrides default parameter
3568  * being set by sysctl as well as FreeBSD implementation
3569  */
3570 static int sctp_setsockopt_auto_asconf(struct sock *sk, char __user *optval,
3571 					unsigned int optlen)
3572 {
3573 	int val;
3574 	struct sctp_sock *sp = sctp_sk(sk);
3575 
3576 	if (optlen < sizeof(int))
3577 		return -EINVAL;
3578 	if (get_user(val, (int __user *)optval))
3579 		return -EFAULT;
3580 	if (!sctp_is_ep_boundall(sk) && val)
3581 		return -EINVAL;
3582 	if ((val && sp->do_auto_asconf) || (!val && !sp->do_auto_asconf))
3583 		return 0;
3584 
3585 	spin_lock_bh(&sock_net(sk)->sctp.addr_wq_lock);
3586 	if (val == 0 && sp->do_auto_asconf) {
3587 		list_del(&sp->auto_asconf_list);
3588 		sp->do_auto_asconf = 0;
3589 	} else if (val && !sp->do_auto_asconf) {
3590 		list_add_tail(&sp->auto_asconf_list,
3591 		    &sock_net(sk)->sctp.auto_asconf_splist);
3592 		sp->do_auto_asconf = 1;
3593 	}
3594 	spin_unlock_bh(&sock_net(sk)->sctp.addr_wq_lock);
3595 	return 0;
3596 }
3597 
3598 /*
3599  * SCTP_PEER_ADDR_THLDS
3600  *
3601  * This option allows us to alter the partially failed threshold for one or all
3602  * transports in an association.  See Section 6.1 of:
3603  * http://www.ietf.org/id/draft-nishida-tsvwg-sctp-failover-05.txt
3604  */
3605 static int sctp_setsockopt_paddr_thresholds(struct sock *sk,
3606 					    char __user *optval,
3607 					    unsigned int optlen)
3608 {
3609 	struct sctp_paddrthlds val;
3610 	struct sctp_transport *trans;
3611 	struct sctp_association *asoc;
3612 
3613 	if (optlen < sizeof(struct sctp_paddrthlds))
3614 		return -EINVAL;
3615 	if (copy_from_user(&val, (struct sctp_paddrthlds __user *)optval,
3616 			   sizeof(struct sctp_paddrthlds)))
3617 		return -EFAULT;
3618 
3619 
3620 	if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
3621 		asoc = sctp_id2assoc(sk, val.spt_assoc_id);
3622 		if (!asoc)
3623 			return -ENOENT;
3624 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
3625 				    transports) {
3626 			if (val.spt_pathmaxrxt)
3627 				trans->pathmaxrxt = val.spt_pathmaxrxt;
3628 			trans->pf_retrans = val.spt_pathpfthld;
3629 		}
3630 
3631 		if (val.spt_pathmaxrxt)
3632 			asoc->pathmaxrxt = val.spt_pathmaxrxt;
3633 		asoc->pf_retrans = val.spt_pathpfthld;
3634 	} else {
3635 		trans = sctp_addr_id2transport(sk, &val.spt_address,
3636 					       val.spt_assoc_id);
3637 		if (!trans)
3638 			return -ENOENT;
3639 
3640 		if (val.spt_pathmaxrxt)
3641 			trans->pathmaxrxt = val.spt_pathmaxrxt;
3642 		trans->pf_retrans = val.spt_pathpfthld;
3643 	}
3644 
3645 	return 0;
3646 }
3647 
3648 static int sctp_setsockopt_recvrcvinfo(struct sock *sk,
3649 				       char __user *optval,
3650 				       unsigned int optlen)
3651 {
3652 	int val;
3653 
3654 	if (optlen < sizeof(int))
3655 		return -EINVAL;
3656 	if (get_user(val, (int __user *) optval))
3657 		return -EFAULT;
3658 
3659 	sctp_sk(sk)->recvrcvinfo = (val == 0) ? 0 : 1;
3660 
3661 	return 0;
3662 }
3663 
3664 static int sctp_setsockopt_recvnxtinfo(struct sock *sk,
3665 				       char __user *optval,
3666 				       unsigned int optlen)
3667 {
3668 	int val;
3669 
3670 	if (optlen < sizeof(int))
3671 		return -EINVAL;
3672 	if (get_user(val, (int __user *) optval))
3673 		return -EFAULT;
3674 
3675 	sctp_sk(sk)->recvnxtinfo = (val == 0) ? 0 : 1;
3676 
3677 	return 0;
3678 }
3679 
3680 static int sctp_setsockopt_pr_supported(struct sock *sk,
3681 					char __user *optval,
3682 					unsigned int optlen)
3683 {
3684 	struct sctp_assoc_value params;
3685 	struct sctp_association *asoc;
3686 	int retval = -EINVAL;
3687 
3688 	if (optlen != sizeof(params))
3689 		goto out;
3690 
3691 	if (copy_from_user(&params, optval, optlen)) {
3692 		retval = -EFAULT;
3693 		goto out;
3694 	}
3695 
3696 	asoc = sctp_id2assoc(sk, params.assoc_id);
3697 	if (asoc) {
3698 		asoc->prsctp_enable = !!params.assoc_value;
3699 	} else if (!params.assoc_id) {
3700 		struct sctp_sock *sp = sctp_sk(sk);
3701 
3702 		sp->ep->prsctp_enable = !!params.assoc_value;
3703 	} else {
3704 		goto out;
3705 	}
3706 
3707 	retval = 0;
3708 
3709 out:
3710 	return retval;
3711 }
3712 
3713 static int sctp_setsockopt_default_prinfo(struct sock *sk,
3714 					  char __user *optval,
3715 					  unsigned int optlen)
3716 {
3717 	struct sctp_default_prinfo info;
3718 	struct sctp_association *asoc;
3719 	int retval = -EINVAL;
3720 
3721 	if (optlen != sizeof(info))
3722 		goto out;
3723 
3724 	if (copy_from_user(&info, optval, sizeof(info))) {
3725 		retval = -EFAULT;
3726 		goto out;
3727 	}
3728 
3729 	if (info.pr_policy & ~SCTP_PR_SCTP_MASK)
3730 		goto out;
3731 
3732 	if (info.pr_policy == SCTP_PR_SCTP_NONE)
3733 		info.pr_value = 0;
3734 
3735 	asoc = sctp_id2assoc(sk, info.pr_assoc_id);
3736 	if (asoc) {
3737 		SCTP_PR_SET_POLICY(asoc->default_flags, info.pr_policy);
3738 		asoc->default_timetolive = info.pr_value;
3739 	} else if (!info.pr_assoc_id) {
3740 		struct sctp_sock *sp = sctp_sk(sk);
3741 
3742 		SCTP_PR_SET_POLICY(sp->default_flags, info.pr_policy);
3743 		sp->default_timetolive = info.pr_value;
3744 	} else {
3745 		goto out;
3746 	}
3747 
3748 	retval = 0;
3749 
3750 out:
3751 	return retval;
3752 }
3753 
3754 /* API 6.2 setsockopt(), getsockopt()
3755  *
3756  * Applications use setsockopt() and getsockopt() to set or retrieve
3757  * socket options.  Socket options are used to change the default
3758  * behavior of sockets calls.  They are described in Section 7.
3759  *
3760  * The syntax is:
3761  *
3762  *   ret = getsockopt(int sd, int level, int optname, void __user *optval,
3763  *                    int __user *optlen);
3764  *   ret = setsockopt(int sd, int level, int optname, const void __user *optval,
3765  *                    int optlen);
3766  *
3767  *   sd      - the socket descript.
3768  *   level   - set to IPPROTO_SCTP for all SCTP options.
3769  *   optname - the option name.
3770  *   optval  - the buffer to store the value of the option.
3771  *   optlen  - the size of the buffer.
3772  */
3773 static int sctp_setsockopt(struct sock *sk, int level, int optname,
3774 			   char __user *optval, unsigned int optlen)
3775 {
3776 	int retval = 0;
3777 
3778 	pr_debug("%s: sk:%p, optname:%d\n", __func__, sk, optname);
3779 
3780 	/* I can hardly begin to describe how wrong this is.  This is
3781 	 * so broken as to be worse than useless.  The API draft
3782 	 * REALLY is NOT helpful here...  I am not convinced that the
3783 	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
3784 	 * are at all well-founded.
3785 	 */
3786 	if (level != SOL_SCTP) {
3787 		struct sctp_af *af = sctp_sk(sk)->pf->af;
3788 		retval = af->setsockopt(sk, level, optname, optval, optlen);
3789 		goto out_nounlock;
3790 	}
3791 
3792 	lock_sock(sk);
3793 
3794 	switch (optname) {
3795 	case SCTP_SOCKOPT_BINDX_ADD:
3796 		/* 'optlen' is the size of the addresses buffer. */
3797 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3798 					       optlen, SCTP_BINDX_ADD_ADDR);
3799 		break;
3800 
3801 	case SCTP_SOCKOPT_BINDX_REM:
3802 		/* 'optlen' is the size of the addresses buffer. */
3803 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3804 					       optlen, SCTP_BINDX_REM_ADDR);
3805 		break;
3806 
3807 	case SCTP_SOCKOPT_CONNECTX_OLD:
3808 		/* 'optlen' is the size of the addresses buffer. */
3809 		retval = sctp_setsockopt_connectx_old(sk,
3810 					    (struct sockaddr __user *)optval,
3811 					    optlen);
3812 		break;
3813 
3814 	case SCTP_SOCKOPT_CONNECTX:
3815 		/* 'optlen' is the size of the addresses buffer. */
3816 		retval = sctp_setsockopt_connectx(sk,
3817 					    (struct sockaddr __user *)optval,
3818 					    optlen);
3819 		break;
3820 
3821 	case SCTP_DISABLE_FRAGMENTS:
3822 		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
3823 		break;
3824 
3825 	case SCTP_EVENTS:
3826 		retval = sctp_setsockopt_events(sk, optval, optlen);
3827 		break;
3828 
3829 	case SCTP_AUTOCLOSE:
3830 		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
3831 		break;
3832 
3833 	case SCTP_PEER_ADDR_PARAMS:
3834 		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
3835 		break;
3836 
3837 	case SCTP_DELAYED_SACK:
3838 		retval = sctp_setsockopt_delayed_ack(sk, optval, optlen);
3839 		break;
3840 	case SCTP_PARTIAL_DELIVERY_POINT:
3841 		retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
3842 		break;
3843 
3844 	case SCTP_INITMSG:
3845 		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
3846 		break;
3847 	case SCTP_DEFAULT_SEND_PARAM:
3848 		retval = sctp_setsockopt_default_send_param(sk, optval,
3849 							    optlen);
3850 		break;
3851 	case SCTP_DEFAULT_SNDINFO:
3852 		retval = sctp_setsockopt_default_sndinfo(sk, optval, optlen);
3853 		break;
3854 	case SCTP_PRIMARY_ADDR:
3855 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
3856 		break;
3857 	case SCTP_SET_PEER_PRIMARY_ADDR:
3858 		retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
3859 		break;
3860 	case SCTP_NODELAY:
3861 		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
3862 		break;
3863 	case SCTP_RTOINFO:
3864 		retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
3865 		break;
3866 	case SCTP_ASSOCINFO:
3867 		retval = sctp_setsockopt_associnfo(sk, optval, optlen);
3868 		break;
3869 	case SCTP_I_WANT_MAPPED_V4_ADDR:
3870 		retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
3871 		break;
3872 	case SCTP_MAXSEG:
3873 		retval = sctp_setsockopt_maxseg(sk, optval, optlen);
3874 		break;
3875 	case SCTP_ADAPTATION_LAYER:
3876 		retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
3877 		break;
3878 	case SCTP_CONTEXT:
3879 		retval = sctp_setsockopt_context(sk, optval, optlen);
3880 		break;
3881 	case SCTP_FRAGMENT_INTERLEAVE:
3882 		retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
3883 		break;
3884 	case SCTP_MAX_BURST:
3885 		retval = sctp_setsockopt_maxburst(sk, optval, optlen);
3886 		break;
3887 	case SCTP_AUTH_CHUNK:
3888 		retval = sctp_setsockopt_auth_chunk(sk, optval, optlen);
3889 		break;
3890 	case SCTP_HMAC_IDENT:
3891 		retval = sctp_setsockopt_hmac_ident(sk, optval, optlen);
3892 		break;
3893 	case SCTP_AUTH_KEY:
3894 		retval = sctp_setsockopt_auth_key(sk, optval, optlen);
3895 		break;
3896 	case SCTP_AUTH_ACTIVE_KEY:
3897 		retval = sctp_setsockopt_active_key(sk, optval, optlen);
3898 		break;
3899 	case SCTP_AUTH_DELETE_KEY:
3900 		retval = sctp_setsockopt_del_key(sk, optval, optlen);
3901 		break;
3902 	case SCTP_AUTO_ASCONF:
3903 		retval = sctp_setsockopt_auto_asconf(sk, optval, optlen);
3904 		break;
3905 	case SCTP_PEER_ADDR_THLDS:
3906 		retval = sctp_setsockopt_paddr_thresholds(sk, optval, optlen);
3907 		break;
3908 	case SCTP_RECVRCVINFO:
3909 		retval = sctp_setsockopt_recvrcvinfo(sk, optval, optlen);
3910 		break;
3911 	case SCTP_RECVNXTINFO:
3912 		retval = sctp_setsockopt_recvnxtinfo(sk, optval, optlen);
3913 		break;
3914 	case SCTP_PR_SUPPORTED:
3915 		retval = sctp_setsockopt_pr_supported(sk, optval, optlen);
3916 		break;
3917 	case SCTP_DEFAULT_PRINFO:
3918 		retval = sctp_setsockopt_default_prinfo(sk, optval, optlen);
3919 		break;
3920 	default:
3921 		retval = -ENOPROTOOPT;
3922 		break;
3923 	}
3924 
3925 	release_sock(sk);
3926 
3927 out_nounlock:
3928 	return retval;
3929 }
3930 
3931 /* API 3.1.6 connect() - UDP Style Syntax
3932  *
3933  * An application may use the connect() call in the UDP model to initiate an
3934  * association without sending data.
3935  *
3936  * The syntax is:
3937  *
3938  * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
3939  *
3940  * sd: the socket descriptor to have a new association added to.
3941  *
3942  * nam: the address structure (either struct sockaddr_in or struct
3943  *    sockaddr_in6 defined in RFC2553 [7]).
3944  *
3945  * len: the size of the address.
3946  */
3947 static int sctp_connect(struct sock *sk, struct sockaddr *addr,
3948 			int addr_len)
3949 {
3950 	int err = 0;
3951 	struct sctp_af *af;
3952 
3953 	lock_sock(sk);
3954 
3955 	pr_debug("%s: sk:%p, sockaddr:%p, addr_len:%d\n", __func__, sk,
3956 		 addr, addr_len);
3957 
3958 	/* Validate addr_len before calling common connect/connectx routine. */
3959 	af = sctp_get_af_specific(addr->sa_family);
3960 	if (!af || addr_len < af->sockaddr_len) {
3961 		err = -EINVAL;
3962 	} else {
3963 		/* Pass correct addr len to common routine (so it knows there
3964 		 * is only one address being passed.
3965 		 */
3966 		err = __sctp_connect(sk, addr, af->sockaddr_len, NULL);
3967 	}
3968 
3969 	release_sock(sk);
3970 	return err;
3971 }
3972 
3973 /* FIXME: Write comments. */
3974 static int sctp_disconnect(struct sock *sk, int flags)
3975 {
3976 	return -EOPNOTSUPP; /* STUB */
3977 }
3978 
3979 /* 4.1.4 accept() - TCP Style Syntax
3980  *
3981  * Applications use accept() call to remove an established SCTP
3982  * association from the accept queue of the endpoint.  A new socket
3983  * descriptor will be returned from accept() to represent the newly
3984  * formed association.
3985  */
3986 static struct sock *sctp_accept(struct sock *sk, int flags, int *err)
3987 {
3988 	struct sctp_sock *sp;
3989 	struct sctp_endpoint *ep;
3990 	struct sock *newsk = NULL;
3991 	struct sctp_association *asoc;
3992 	long timeo;
3993 	int error = 0;
3994 
3995 	lock_sock(sk);
3996 
3997 	sp = sctp_sk(sk);
3998 	ep = sp->ep;
3999 
4000 	if (!sctp_style(sk, TCP)) {
4001 		error = -EOPNOTSUPP;
4002 		goto out;
4003 	}
4004 
4005 	if (!sctp_sstate(sk, LISTENING)) {
4006 		error = -EINVAL;
4007 		goto out;
4008 	}
4009 
4010 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
4011 
4012 	error = sctp_wait_for_accept(sk, timeo);
4013 	if (error)
4014 		goto out;
4015 
4016 	/* We treat the list of associations on the endpoint as the accept
4017 	 * queue and pick the first association on the list.
4018 	 */
4019 	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
4020 
4021 	newsk = sp->pf->create_accept_sk(sk, asoc);
4022 	if (!newsk) {
4023 		error = -ENOMEM;
4024 		goto out;
4025 	}
4026 
4027 	/* Populate the fields of the newsk from the oldsk and migrate the
4028 	 * asoc to the newsk.
4029 	 */
4030 	sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
4031 
4032 out:
4033 	release_sock(sk);
4034 	*err = error;
4035 	return newsk;
4036 }
4037 
4038 /* The SCTP ioctl handler. */
4039 static int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
4040 {
4041 	int rc = -ENOTCONN;
4042 
4043 	lock_sock(sk);
4044 
4045 	/*
4046 	 * SEQPACKET-style sockets in LISTENING state are valid, for
4047 	 * SCTP, so only discard TCP-style sockets in LISTENING state.
4048 	 */
4049 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
4050 		goto out;
4051 
4052 	switch (cmd) {
4053 	case SIOCINQ: {
4054 		struct sk_buff *skb;
4055 		unsigned int amount = 0;
4056 
4057 		skb = skb_peek(&sk->sk_receive_queue);
4058 		if (skb != NULL) {
4059 			/*
4060 			 * We will only return the amount of this packet since
4061 			 * that is all that will be read.
4062 			 */
4063 			amount = skb->len;
4064 		}
4065 		rc = put_user(amount, (int __user *)arg);
4066 		break;
4067 	}
4068 	default:
4069 		rc = -ENOIOCTLCMD;
4070 		break;
4071 	}
4072 out:
4073 	release_sock(sk);
4074 	return rc;
4075 }
4076 
4077 /* This is the function which gets called during socket creation to
4078  * initialized the SCTP-specific portion of the sock.
4079  * The sock structure should already be zero-filled memory.
4080  */
4081 static int sctp_init_sock(struct sock *sk)
4082 {
4083 	struct net *net = sock_net(sk);
4084 	struct sctp_sock *sp;
4085 
4086 	pr_debug("%s: sk:%p\n", __func__, sk);
4087 
4088 	sp = sctp_sk(sk);
4089 
4090 	/* Initialize the SCTP per socket area.  */
4091 	switch (sk->sk_type) {
4092 	case SOCK_SEQPACKET:
4093 		sp->type = SCTP_SOCKET_UDP;
4094 		break;
4095 	case SOCK_STREAM:
4096 		sp->type = SCTP_SOCKET_TCP;
4097 		break;
4098 	default:
4099 		return -ESOCKTNOSUPPORT;
4100 	}
4101 
4102 	sk->sk_gso_type = SKB_GSO_SCTP;
4103 
4104 	/* Initialize default send parameters. These parameters can be
4105 	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
4106 	 */
4107 	sp->default_stream = 0;
4108 	sp->default_ppid = 0;
4109 	sp->default_flags = 0;
4110 	sp->default_context = 0;
4111 	sp->default_timetolive = 0;
4112 
4113 	sp->default_rcv_context = 0;
4114 	sp->max_burst = net->sctp.max_burst;
4115 
4116 	sp->sctp_hmac_alg = net->sctp.sctp_hmac_alg;
4117 
4118 	/* Initialize default setup parameters. These parameters
4119 	 * can be modified with the SCTP_INITMSG socket option or
4120 	 * overridden by the SCTP_INIT CMSG.
4121 	 */
4122 	sp->initmsg.sinit_num_ostreams   = sctp_max_outstreams;
4123 	sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
4124 	sp->initmsg.sinit_max_attempts   = net->sctp.max_retrans_init;
4125 	sp->initmsg.sinit_max_init_timeo = net->sctp.rto_max;
4126 
4127 	/* Initialize default RTO related parameters.  These parameters can
4128 	 * be modified for with the SCTP_RTOINFO socket option.
4129 	 */
4130 	sp->rtoinfo.srto_initial = net->sctp.rto_initial;
4131 	sp->rtoinfo.srto_max     = net->sctp.rto_max;
4132 	sp->rtoinfo.srto_min     = net->sctp.rto_min;
4133 
4134 	/* Initialize default association related parameters. These parameters
4135 	 * can be modified with the SCTP_ASSOCINFO socket option.
4136 	 */
4137 	sp->assocparams.sasoc_asocmaxrxt = net->sctp.max_retrans_association;
4138 	sp->assocparams.sasoc_number_peer_destinations = 0;
4139 	sp->assocparams.sasoc_peer_rwnd = 0;
4140 	sp->assocparams.sasoc_local_rwnd = 0;
4141 	sp->assocparams.sasoc_cookie_life = net->sctp.valid_cookie_life;
4142 
4143 	/* Initialize default event subscriptions. By default, all the
4144 	 * options are off.
4145 	 */
4146 	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
4147 
4148 	/* Default Peer Address Parameters.  These defaults can
4149 	 * be modified via SCTP_PEER_ADDR_PARAMS
4150 	 */
4151 	sp->hbinterval  = net->sctp.hb_interval;
4152 	sp->pathmaxrxt  = net->sctp.max_retrans_path;
4153 	sp->pathmtu     = 0; /* allow default discovery */
4154 	sp->sackdelay   = net->sctp.sack_timeout;
4155 	sp->sackfreq	= 2;
4156 	sp->param_flags = SPP_HB_ENABLE |
4157 			  SPP_PMTUD_ENABLE |
4158 			  SPP_SACKDELAY_ENABLE;
4159 
4160 	/* If enabled no SCTP message fragmentation will be performed.
4161 	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
4162 	 */
4163 	sp->disable_fragments = 0;
4164 
4165 	/* Enable Nagle algorithm by default.  */
4166 	sp->nodelay           = 0;
4167 
4168 	sp->recvrcvinfo = 0;
4169 	sp->recvnxtinfo = 0;
4170 
4171 	/* Enable by default. */
4172 	sp->v4mapped          = 1;
4173 
4174 	/* Auto-close idle associations after the configured
4175 	 * number of seconds.  A value of 0 disables this
4176 	 * feature.  Configure through the SCTP_AUTOCLOSE socket option,
4177 	 * for UDP-style sockets only.
4178 	 */
4179 	sp->autoclose         = 0;
4180 
4181 	/* User specified fragmentation limit. */
4182 	sp->user_frag         = 0;
4183 
4184 	sp->adaptation_ind = 0;
4185 
4186 	sp->pf = sctp_get_pf_specific(sk->sk_family);
4187 
4188 	/* Control variables for partial data delivery. */
4189 	atomic_set(&sp->pd_mode, 0);
4190 	skb_queue_head_init(&sp->pd_lobby);
4191 	sp->frag_interleave = 0;
4192 
4193 	/* Create a per socket endpoint structure.  Even if we
4194 	 * change the data structure relationships, this may still
4195 	 * be useful for storing pre-connect address information.
4196 	 */
4197 	sp->ep = sctp_endpoint_new(sk, GFP_KERNEL);
4198 	if (!sp->ep)
4199 		return -ENOMEM;
4200 
4201 	sp->hmac = NULL;
4202 
4203 	sk->sk_destruct = sctp_destruct_sock;
4204 
4205 	SCTP_DBG_OBJCNT_INC(sock);
4206 
4207 	local_bh_disable();
4208 	percpu_counter_inc(&sctp_sockets_allocated);
4209 	sock_prot_inuse_add(net, sk->sk_prot, 1);
4210 
4211 	/* Nothing can fail after this block, otherwise
4212 	 * sctp_destroy_sock() will be called without addr_wq_lock held
4213 	 */
4214 	if (net->sctp.default_auto_asconf) {
4215 		spin_lock(&sock_net(sk)->sctp.addr_wq_lock);
4216 		list_add_tail(&sp->auto_asconf_list,
4217 		    &net->sctp.auto_asconf_splist);
4218 		sp->do_auto_asconf = 1;
4219 		spin_unlock(&sock_net(sk)->sctp.addr_wq_lock);
4220 	} else {
4221 		sp->do_auto_asconf = 0;
4222 	}
4223 
4224 	local_bh_enable();
4225 
4226 	return 0;
4227 }
4228 
4229 /* Cleanup any SCTP per socket resources. Must be called with
4230  * sock_net(sk)->sctp.addr_wq_lock held if sp->do_auto_asconf is true
4231  */
4232 static void sctp_destroy_sock(struct sock *sk)
4233 {
4234 	struct sctp_sock *sp;
4235 
4236 	pr_debug("%s: sk:%p\n", __func__, sk);
4237 
4238 	/* Release our hold on the endpoint. */
4239 	sp = sctp_sk(sk);
4240 	/* This could happen during socket init, thus we bail out
4241 	 * early, since the rest of the below is not setup either.
4242 	 */
4243 	if (sp->ep == NULL)
4244 		return;
4245 
4246 	if (sp->do_auto_asconf) {
4247 		sp->do_auto_asconf = 0;
4248 		list_del(&sp->auto_asconf_list);
4249 	}
4250 	sctp_endpoint_free(sp->ep);
4251 	local_bh_disable();
4252 	percpu_counter_dec(&sctp_sockets_allocated);
4253 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
4254 	local_bh_enable();
4255 }
4256 
4257 /* Triggered when there are no references on the socket anymore */
4258 static void sctp_destruct_sock(struct sock *sk)
4259 {
4260 	struct sctp_sock *sp = sctp_sk(sk);
4261 
4262 	/* Free up the HMAC transform. */
4263 	crypto_free_shash(sp->hmac);
4264 
4265 	inet_sock_destruct(sk);
4266 }
4267 
4268 /* API 4.1.7 shutdown() - TCP Style Syntax
4269  *     int shutdown(int socket, int how);
4270  *
4271  *     sd      - the socket descriptor of the association to be closed.
4272  *     how     - Specifies the type of shutdown.  The  values  are
4273  *               as follows:
4274  *               SHUT_RD
4275  *                     Disables further receive operations. No SCTP
4276  *                     protocol action is taken.
4277  *               SHUT_WR
4278  *                     Disables further send operations, and initiates
4279  *                     the SCTP shutdown sequence.
4280  *               SHUT_RDWR
4281  *                     Disables further send  and  receive  operations
4282  *                     and initiates the SCTP shutdown sequence.
4283  */
4284 static void sctp_shutdown(struct sock *sk, int how)
4285 {
4286 	struct net *net = sock_net(sk);
4287 	struct sctp_endpoint *ep;
4288 
4289 	if (!sctp_style(sk, TCP))
4290 		return;
4291 
4292 	ep = sctp_sk(sk)->ep;
4293 	if (how & SEND_SHUTDOWN && !list_empty(&ep->asocs)) {
4294 		struct sctp_association *asoc;
4295 
4296 		sk->sk_state = SCTP_SS_CLOSING;
4297 		asoc = list_entry(ep->asocs.next,
4298 				  struct sctp_association, asocs);
4299 		sctp_primitive_SHUTDOWN(net, asoc, NULL);
4300 	}
4301 }
4302 
4303 int sctp_get_sctp_info(struct sock *sk, struct sctp_association *asoc,
4304 		       struct sctp_info *info)
4305 {
4306 	struct sctp_transport *prim;
4307 	struct list_head *pos;
4308 	int mask;
4309 
4310 	memset(info, 0, sizeof(*info));
4311 	if (!asoc) {
4312 		struct sctp_sock *sp = sctp_sk(sk);
4313 
4314 		info->sctpi_s_autoclose = sp->autoclose;
4315 		info->sctpi_s_adaptation_ind = sp->adaptation_ind;
4316 		info->sctpi_s_pd_point = sp->pd_point;
4317 		info->sctpi_s_nodelay = sp->nodelay;
4318 		info->sctpi_s_disable_fragments = sp->disable_fragments;
4319 		info->sctpi_s_v4mapped = sp->v4mapped;
4320 		info->sctpi_s_frag_interleave = sp->frag_interleave;
4321 		info->sctpi_s_type = sp->type;
4322 
4323 		return 0;
4324 	}
4325 
4326 	info->sctpi_tag = asoc->c.my_vtag;
4327 	info->sctpi_state = asoc->state;
4328 	info->sctpi_rwnd = asoc->a_rwnd;
4329 	info->sctpi_unackdata = asoc->unack_data;
4330 	info->sctpi_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
4331 	info->sctpi_instrms = asoc->c.sinit_max_instreams;
4332 	info->sctpi_outstrms = asoc->c.sinit_num_ostreams;
4333 	list_for_each(pos, &asoc->base.inqueue.in_chunk_list)
4334 		info->sctpi_inqueue++;
4335 	list_for_each(pos, &asoc->outqueue.out_chunk_list)
4336 		info->sctpi_outqueue++;
4337 	info->sctpi_overall_error = asoc->overall_error_count;
4338 	info->sctpi_max_burst = asoc->max_burst;
4339 	info->sctpi_maxseg = asoc->frag_point;
4340 	info->sctpi_peer_rwnd = asoc->peer.rwnd;
4341 	info->sctpi_peer_tag = asoc->c.peer_vtag;
4342 
4343 	mask = asoc->peer.ecn_capable << 1;
4344 	mask = (mask | asoc->peer.ipv4_address) << 1;
4345 	mask = (mask | asoc->peer.ipv6_address) << 1;
4346 	mask = (mask | asoc->peer.hostname_address) << 1;
4347 	mask = (mask | asoc->peer.asconf_capable) << 1;
4348 	mask = (mask | asoc->peer.prsctp_capable) << 1;
4349 	mask = (mask | asoc->peer.auth_capable);
4350 	info->sctpi_peer_capable = mask;
4351 	mask = asoc->peer.sack_needed << 1;
4352 	mask = (mask | asoc->peer.sack_generation) << 1;
4353 	mask = (mask | asoc->peer.zero_window_announced);
4354 	info->sctpi_peer_sack = mask;
4355 
4356 	info->sctpi_isacks = asoc->stats.isacks;
4357 	info->sctpi_osacks = asoc->stats.osacks;
4358 	info->sctpi_opackets = asoc->stats.opackets;
4359 	info->sctpi_ipackets = asoc->stats.ipackets;
4360 	info->sctpi_rtxchunks = asoc->stats.rtxchunks;
4361 	info->sctpi_outofseqtsns = asoc->stats.outofseqtsns;
4362 	info->sctpi_idupchunks = asoc->stats.idupchunks;
4363 	info->sctpi_gapcnt = asoc->stats.gapcnt;
4364 	info->sctpi_ouodchunks = asoc->stats.ouodchunks;
4365 	info->sctpi_iuodchunks = asoc->stats.iuodchunks;
4366 	info->sctpi_oodchunks = asoc->stats.oodchunks;
4367 	info->sctpi_iodchunks = asoc->stats.iodchunks;
4368 	info->sctpi_octrlchunks = asoc->stats.octrlchunks;
4369 	info->sctpi_ictrlchunks = asoc->stats.ictrlchunks;
4370 
4371 	prim = asoc->peer.primary_path;
4372 	memcpy(&info->sctpi_p_address, &prim->ipaddr,
4373 	       sizeof(struct sockaddr_storage));
4374 	info->sctpi_p_state = prim->state;
4375 	info->sctpi_p_cwnd = prim->cwnd;
4376 	info->sctpi_p_srtt = prim->srtt;
4377 	info->sctpi_p_rto = jiffies_to_msecs(prim->rto);
4378 	info->sctpi_p_hbinterval = prim->hbinterval;
4379 	info->sctpi_p_pathmaxrxt = prim->pathmaxrxt;
4380 	info->sctpi_p_sackdelay = jiffies_to_msecs(prim->sackdelay);
4381 	info->sctpi_p_ssthresh = prim->ssthresh;
4382 	info->sctpi_p_partial_bytes_acked = prim->partial_bytes_acked;
4383 	info->sctpi_p_flight_size = prim->flight_size;
4384 	info->sctpi_p_error = prim->error_count;
4385 
4386 	return 0;
4387 }
4388 EXPORT_SYMBOL_GPL(sctp_get_sctp_info);
4389 
4390 /* use callback to avoid exporting the core structure */
4391 int sctp_transport_walk_start(struct rhashtable_iter *iter)
4392 {
4393 	int err;
4394 
4395 	rhltable_walk_enter(&sctp_transport_hashtable, iter);
4396 
4397 	err = rhashtable_walk_start(iter);
4398 	if (err && err != -EAGAIN) {
4399 		rhashtable_walk_stop(iter);
4400 		rhashtable_walk_exit(iter);
4401 		return err;
4402 	}
4403 
4404 	return 0;
4405 }
4406 
4407 void sctp_transport_walk_stop(struct rhashtable_iter *iter)
4408 {
4409 	rhashtable_walk_stop(iter);
4410 	rhashtable_walk_exit(iter);
4411 }
4412 
4413 struct sctp_transport *sctp_transport_get_next(struct net *net,
4414 					       struct rhashtable_iter *iter)
4415 {
4416 	struct sctp_transport *t;
4417 
4418 	t = rhashtable_walk_next(iter);
4419 	for (; t; t = rhashtable_walk_next(iter)) {
4420 		if (IS_ERR(t)) {
4421 			if (PTR_ERR(t) == -EAGAIN)
4422 				continue;
4423 			break;
4424 		}
4425 
4426 		if (net_eq(sock_net(t->asoc->base.sk), net) &&
4427 		    t->asoc->peer.primary_path == t)
4428 			break;
4429 	}
4430 
4431 	return t;
4432 }
4433 
4434 struct sctp_transport *sctp_transport_get_idx(struct net *net,
4435 					      struct rhashtable_iter *iter,
4436 					      int pos)
4437 {
4438 	void *obj = SEQ_START_TOKEN;
4439 
4440 	while (pos && (obj = sctp_transport_get_next(net, iter)) &&
4441 	       !IS_ERR(obj))
4442 		pos--;
4443 
4444 	return obj;
4445 }
4446 
4447 int sctp_for_each_endpoint(int (*cb)(struct sctp_endpoint *, void *),
4448 			   void *p) {
4449 	int err = 0;
4450 	int hash = 0;
4451 	struct sctp_ep_common *epb;
4452 	struct sctp_hashbucket *head;
4453 
4454 	for (head = sctp_ep_hashtable; hash < sctp_ep_hashsize;
4455 	     hash++, head++) {
4456 		read_lock(&head->lock);
4457 		sctp_for_each_hentry(epb, &head->chain) {
4458 			err = cb(sctp_ep(epb), p);
4459 			if (err)
4460 				break;
4461 		}
4462 		read_unlock(&head->lock);
4463 	}
4464 
4465 	return err;
4466 }
4467 EXPORT_SYMBOL_GPL(sctp_for_each_endpoint);
4468 
4469 int sctp_transport_lookup_process(int (*cb)(struct sctp_transport *, void *),
4470 				  struct net *net,
4471 				  const union sctp_addr *laddr,
4472 				  const union sctp_addr *paddr, void *p)
4473 {
4474 	struct sctp_transport *transport;
4475 	int err;
4476 
4477 	rcu_read_lock();
4478 	transport = sctp_addrs_lookup_transport(net, laddr, paddr);
4479 	rcu_read_unlock();
4480 	if (!transport)
4481 		return -ENOENT;
4482 
4483 	err = cb(transport, p);
4484 	sctp_transport_put(transport);
4485 
4486 	return err;
4487 }
4488 EXPORT_SYMBOL_GPL(sctp_transport_lookup_process);
4489 
4490 int sctp_for_each_transport(int (*cb)(struct sctp_transport *, void *),
4491 			    struct net *net, int pos, void *p) {
4492 	struct rhashtable_iter hti;
4493 	void *obj;
4494 	int err;
4495 
4496 	err = sctp_transport_walk_start(&hti);
4497 	if (err)
4498 		return err;
4499 
4500 	sctp_transport_get_idx(net, &hti, pos);
4501 	obj = sctp_transport_get_next(net, &hti);
4502 	for (; obj && !IS_ERR(obj); obj = sctp_transport_get_next(net, &hti)) {
4503 		struct sctp_transport *transport = obj;
4504 
4505 		if (!sctp_transport_hold(transport))
4506 			continue;
4507 		err = cb(transport, p);
4508 		sctp_transport_put(transport);
4509 		if (err)
4510 			break;
4511 	}
4512 	sctp_transport_walk_stop(&hti);
4513 
4514 	return err;
4515 }
4516 EXPORT_SYMBOL_GPL(sctp_for_each_transport);
4517 
4518 /* 7.2.1 Association Status (SCTP_STATUS)
4519 
4520  * Applications can retrieve current status information about an
4521  * association, including association state, peer receiver window size,
4522  * number of unacked data chunks, and number of data chunks pending
4523  * receipt.  This information is read-only.
4524  */
4525 static int sctp_getsockopt_sctp_status(struct sock *sk, int len,
4526 				       char __user *optval,
4527 				       int __user *optlen)
4528 {
4529 	struct sctp_status status;
4530 	struct sctp_association *asoc = NULL;
4531 	struct sctp_transport *transport;
4532 	sctp_assoc_t associd;
4533 	int retval = 0;
4534 
4535 	if (len < sizeof(status)) {
4536 		retval = -EINVAL;
4537 		goto out;
4538 	}
4539 
4540 	len = sizeof(status);
4541 	if (copy_from_user(&status, optval, len)) {
4542 		retval = -EFAULT;
4543 		goto out;
4544 	}
4545 
4546 	associd = status.sstat_assoc_id;
4547 	asoc = sctp_id2assoc(sk, associd);
4548 	if (!asoc) {
4549 		retval = -EINVAL;
4550 		goto out;
4551 	}
4552 
4553 	transport = asoc->peer.primary_path;
4554 
4555 	status.sstat_assoc_id = sctp_assoc2id(asoc);
4556 	status.sstat_state = sctp_assoc_to_state(asoc);
4557 	status.sstat_rwnd =  asoc->peer.rwnd;
4558 	status.sstat_unackdata = asoc->unack_data;
4559 
4560 	status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
4561 	status.sstat_instrms = asoc->c.sinit_max_instreams;
4562 	status.sstat_outstrms = asoc->c.sinit_num_ostreams;
4563 	status.sstat_fragmentation_point = asoc->frag_point;
4564 	status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
4565 	memcpy(&status.sstat_primary.spinfo_address, &transport->ipaddr,
4566 			transport->af_specific->sockaddr_len);
4567 	/* Map ipv4 address into v4-mapped-on-v6 address.  */
4568 	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sctp_sk(sk),
4569 		(union sctp_addr *)&status.sstat_primary.spinfo_address);
4570 	status.sstat_primary.spinfo_state = transport->state;
4571 	status.sstat_primary.spinfo_cwnd = transport->cwnd;
4572 	status.sstat_primary.spinfo_srtt = transport->srtt;
4573 	status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
4574 	status.sstat_primary.spinfo_mtu = transport->pathmtu;
4575 
4576 	if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
4577 		status.sstat_primary.spinfo_state = SCTP_ACTIVE;
4578 
4579 	if (put_user(len, optlen)) {
4580 		retval = -EFAULT;
4581 		goto out;
4582 	}
4583 
4584 	pr_debug("%s: len:%d, state:%d, rwnd:%d, assoc_id:%d\n",
4585 		 __func__, len, status.sstat_state, status.sstat_rwnd,
4586 		 status.sstat_assoc_id);
4587 
4588 	if (copy_to_user(optval, &status, len)) {
4589 		retval = -EFAULT;
4590 		goto out;
4591 	}
4592 
4593 out:
4594 	return retval;
4595 }
4596 
4597 
4598 /* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
4599  *
4600  * Applications can retrieve information about a specific peer address
4601  * of an association, including its reachability state, congestion
4602  * window, and retransmission timer values.  This information is
4603  * read-only.
4604  */
4605 static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
4606 					  char __user *optval,
4607 					  int __user *optlen)
4608 {
4609 	struct sctp_paddrinfo pinfo;
4610 	struct sctp_transport *transport;
4611 	int retval = 0;
4612 
4613 	if (len < sizeof(pinfo)) {
4614 		retval = -EINVAL;
4615 		goto out;
4616 	}
4617 
4618 	len = sizeof(pinfo);
4619 	if (copy_from_user(&pinfo, optval, len)) {
4620 		retval = -EFAULT;
4621 		goto out;
4622 	}
4623 
4624 	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
4625 					   pinfo.spinfo_assoc_id);
4626 	if (!transport)
4627 		return -EINVAL;
4628 
4629 	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
4630 	pinfo.spinfo_state = transport->state;
4631 	pinfo.spinfo_cwnd = transport->cwnd;
4632 	pinfo.spinfo_srtt = transport->srtt;
4633 	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
4634 	pinfo.spinfo_mtu = transport->pathmtu;
4635 
4636 	if (pinfo.spinfo_state == SCTP_UNKNOWN)
4637 		pinfo.spinfo_state = SCTP_ACTIVE;
4638 
4639 	if (put_user(len, optlen)) {
4640 		retval = -EFAULT;
4641 		goto out;
4642 	}
4643 
4644 	if (copy_to_user(optval, &pinfo, len)) {
4645 		retval = -EFAULT;
4646 		goto out;
4647 	}
4648 
4649 out:
4650 	return retval;
4651 }
4652 
4653 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
4654  *
4655  * This option is a on/off flag.  If enabled no SCTP message
4656  * fragmentation will be performed.  Instead if a message being sent
4657  * exceeds the current PMTU size, the message will NOT be sent and
4658  * instead a error will be indicated to the user.
4659  */
4660 static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
4661 					char __user *optval, int __user *optlen)
4662 {
4663 	int val;
4664 
4665 	if (len < sizeof(int))
4666 		return -EINVAL;
4667 
4668 	len = sizeof(int);
4669 	val = (sctp_sk(sk)->disable_fragments == 1);
4670 	if (put_user(len, optlen))
4671 		return -EFAULT;
4672 	if (copy_to_user(optval, &val, len))
4673 		return -EFAULT;
4674 	return 0;
4675 }
4676 
4677 /* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
4678  *
4679  * This socket option is used to specify various notifications and
4680  * ancillary data the user wishes to receive.
4681  */
4682 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
4683 				  int __user *optlen)
4684 {
4685 	if (len == 0)
4686 		return -EINVAL;
4687 	if (len > sizeof(struct sctp_event_subscribe))
4688 		len = sizeof(struct sctp_event_subscribe);
4689 	if (put_user(len, optlen))
4690 		return -EFAULT;
4691 	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
4692 		return -EFAULT;
4693 	return 0;
4694 }
4695 
4696 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
4697  *
4698  * This socket option is applicable to the UDP-style socket only.  When
4699  * set it will cause associations that are idle for more than the
4700  * specified number of seconds to automatically close.  An association
4701  * being idle is defined an association that has NOT sent or received
4702  * user data.  The special value of '0' indicates that no automatic
4703  * close of any associations should be performed.  The option expects an
4704  * integer defining the number of seconds of idle time before an
4705  * association is closed.
4706  */
4707 static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
4708 {
4709 	/* Applicable to UDP-style socket only */
4710 	if (sctp_style(sk, TCP))
4711 		return -EOPNOTSUPP;
4712 	if (len < sizeof(int))
4713 		return -EINVAL;
4714 	len = sizeof(int);
4715 	if (put_user(len, optlen))
4716 		return -EFAULT;
4717 	if (copy_to_user(optval, &sctp_sk(sk)->autoclose, sizeof(int)))
4718 		return -EFAULT;
4719 	return 0;
4720 }
4721 
4722 /* Helper routine to branch off an association to a new socket.  */
4723 int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp)
4724 {
4725 	struct sctp_association *asoc = sctp_id2assoc(sk, id);
4726 	struct sctp_sock *sp = sctp_sk(sk);
4727 	struct socket *sock;
4728 	int err = 0;
4729 
4730 	if (!asoc)
4731 		return -EINVAL;
4732 
4733 	/* An association cannot be branched off from an already peeled-off
4734 	 * socket, nor is this supported for tcp style sockets.
4735 	 */
4736 	if (!sctp_style(sk, UDP))
4737 		return -EINVAL;
4738 
4739 	/* Create a new socket.  */
4740 	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
4741 	if (err < 0)
4742 		return err;
4743 
4744 	sctp_copy_sock(sock->sk, sk, asoc);
4745 
4746 	/* Make peeled-off sockets more like 1-1 accepted sockets.
4747 	 * Set the daddr and initialize id to something more random
4748 	 */
4749 	sp->pf->to_sk_daddr(&asoc->peer.primary_addr, sk);
4750 
4751 	/* Populate the fields of the newsk from the oldsk and migrate the
4752 	 * asoc to the newsk.
4753 	 */
4754 	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
4755 
4756 	*sockp = sock;
4757 
4758 	return err;
4759 }
4760 EXPORT_SYMBOL(sctp_do_peeloff);
4761 
4762 static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
4763 {
4764 	sctp_peeloff_arg_t peeloff;
4765 	struct socket *newsock;
4766 	struct file *newfile;
4767 	int retval = 0;
4768 
4769 	if (len < sizeof(sctp_peeloff_arg_t))
4770 		return -EINVAL;
4771 	len = sizeof(sctp_peeloff_arg_t);
4772 	if (copy_from_user(&peeloff, optval, len))
4773 		return -EFAULT;
4774 
4775 	retval = sctp_do_peeloff(sk, peeloff.associd, &newsock);
4776 	if (retval < 0)
4777 		goto out;
4778 
4779 	/* Map the socket to an unused fd that can be returned to the user.  */
4780 	retval = get_unused_fd_flags(0);
4781 	if (retval < 0) {
4782 		sock_release(newsock);
4783 		goto out;
4784 	}
4785 
4786 	newfile = sock_alloc_file(newsock, 0, NULL);
4787 	if (IS_ERR(newfile)) {
4788 		put_unused_fd(retval);
4789 		sock_release(newsock);
4790 		return PTR_ERR(newfile);
4791 	}
4792 
4793 	pr_debug("%s: sk:%p, newsk:%p, sd:%d\n", __func__, sk, newsock->sk,
4794 		 retval);
4795 
4796 	/* Return the fd mapped to the new socket.  */
4797 	if (put_user(len, optlen)) {
4798 		fput(newfile);
4799 		put_unused_fd(retval);
4800 		return -EFAULT;
4801 	}
4802 	peeloff.sd = retval;
4803 	if (copy_to_user(optval, &peeloff, len)) {
4804 		fput(newfile);
4805 		put_unused_fd(retval);
4806 		return -EFAULT;
4807 	}
4808 	fd_install(retval, newfile);
4809 out:
4810 	return retval;
4811 }
4812 
4813 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
4814  *
4815  * Applications can enable or disable heartbeats for any peer address of
4816  * an association, modify an address's heartbeat interval, force a
4817  * heartbeat to be sent immediately, and adjust the address's maximum
4818  * number of retransmissions sent before an address is considered
4819  * unreachable.  The following structure is used to access and modify an
4820  * address's parameters:
4821  *
4822  *  struct sctp_paddrparams {
4823  *     sctp_assoc_t            spp_assoc_id;
4824  *     struct sockaddr_storage spp_address;
4825  *     uint32_t                spp_hbinterval;
4826  *     uint16_t                spp_pathmaxrxt;
4827  *     uint32_t                spp_pathmtu;
4828  *     uint32_t                spp_sackdelay;
4829  *     uint32_t                spp_flags;
4830  * };
4831  *
4832  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
4833  *                     application, and identifies the association for
4834  *                     this query.
4835  *   spp_address     - This specifies which address is of interest.
4836  *   spp_hbinterval  - This contains the value of the heartbeat interval,
4837  *                     in milliseconds.  If a  value of zero
4838  *                     is present in this field then no changes are to
4839  *                     be made to this parameter.
4840  *   spp_pathmaxrxt  - This contains the maximum number of
4841  *                     retransmissions before this address shall be
4842  *                     considered unreachable. If a  value of zero
4843  *                     is present in this field then no changes are to
4844  *                     be made to this parameter.
4845  *   spp_pathmtu     - When Path MTU discovery is disabled the value
4846  *                     specified here will be the "fixed" path mtu.
4847  *                     Note that if the spp_address field is empty
4848  *                     then all associations on this address will
4849  *                     have this fixed path mtu set upon them.
4850  *
4851  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
4852  *                     the number of milliseconds that sacks will be delayed
4853  *                     for. This value will apply to all addresses of an
4854  *                     association if the spp_address field is empty. Note
4855  *                     also, that if delayed sack is enabled and this
4856  *                     value is set to 0, no change is made to the last
4857  *                     recorded delayed sack timer value.
4858  *
4859  *   spp_flags       - These flags are used to control various features
4860  *                     on an association. The flag field may contain
4861  *                     zero or more of the following options.
4862  *
4863  *                     SPP_HB_ENABLE  - Enable heartbeats on the
4864  *                     specified address. Note that if the address
4865  *                     field is empty all addresses for the association
4866  *                     have heartbeats enabled upon them.
4867  *
4868  *                     SPP_HB_DISABLE - Disable heartbeats on the
4869  *                     speicifed address. Note that if the address
4870  *                     field is empty all addresses for the association
4871  *                     will have their heartbeats disabled. Note also
4872  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
4873  *                     mutually exclusive, only one of these two should
4874  *                     be specified. Enabling both fields will have
4875  *                     undetermined results.
4876  *
4877  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
4878  *                     to be made immediately.
4879  *
4880  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
4881  *                     discovery upon the specified address. Note that
4882  *                     if the address feild is empty then all addresses
4883  *                     on the association are effected.
4884  *
4885  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
4886  *                     discovery upon the specified address. Note that
4887  *                     if the address feild is empty then all addresses
4888  *                     on the association are effected. Not also that
4889  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
4890  *                     exclusive. Enabling both will have undetermined
4891  *                     results.
4892  *
4893  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
4894  *                     on delayed sack. The time specified in spp_sackdelay
4895  *                     is used to specify the sack delay for this address. Note
4896  *                     that if spp_address is empty then all addresses will
4897  *                     enable delayed sack and take on the sack delay
4898  *                     value specified in spp_sackdelay.
4899  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
4900  *                     off delayed sack. If the spp_address field is blank then
4901  *                     delayed sack is disabled for the entire association. Note
4902  *                     also that this field is mutually exclusive to
4903  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
4904  *                     results.
4905  */
4906 static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
4907 					    char __user *optval, int __user *optlen)
4908 {
4909 	struct sctp_paddrparams  params;
4910 	struct sctp_transport   *trans = NULL;
4911 	struct sctp_association *asoc = NULL;
4912 	struct sctp_sock        *sp = sctp_sk(sk);
4913 
4914 	if (len < sizeof(struct sctp_paddrparams))
4915 		return -EINVAL;
4916 	len = sizeof(struct sctp_paddrparams);
4917 	if (copy_from_user(&params, optval, len))
4918 		return -EFAULT;
4919 
4920 	/* If an address other than INADDR_ANY is specified, and
4921 	 * no transport is found, then the request is invalid.
4922 	 */
4923 	if (!sctp_is_any(sk, (union sctp_addr *)&params.spp_address)) {
4924 		trans = sctp_addr_id2transport(sk, &params.spp_address,
4925 					       params.spp_assoc_id);
4926 		if (!trans) {
4927 			pr_debug("%s: failed no transport\n", __func__);
4928 			return -EINVAL;
4929 		}
4930 	}
4931 
4932 	/* Get association, if assoc_id != 0 and the socket is a one
4933 	 * to many style socket, and an association was not found, then
4934 	 * the id was invalid.
4935 	 */
4936 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
4937 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
4938 		pr_debug("%s: failed no association\n", __func__);
4939 		return -EINVAL;
4940 	}
4941 
4942 	if (trans) {
4943 		/* Fetch transport values. */
4944 		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
4945 		params.spp_pathmtu    = trans->pathmtu;
4946 		params.spp_pathmaxrxt = trans->pathmaxrxt;
4947 		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
4948 
4949 		/*draft-11 doesn't say what to return in spp_flags*/
4950 		params.spp_flags      = trans->param_flags;
4951 	} else if (asoc) {
4952 		/* Fetch association values. */
4953 		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
4954 		params.spp_pathmtu    = asoc->pathmtu;
4955 		params.spp_pathmaxrxt = asoc->pathmaxrxt;
4956 		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
4957 
4958 		/*draft-11 doesn't say what to return in spp_flags*/
4959 		params.spp_flags      = asoc->param_flags;
4960 	} else {
4961 		/* Fetch socket values. */
4962 		params.spp_hbinterval = sp->hbinterval;
4963 		params.spp_pathmtu    = sp->pathmtu;
4964 		params.spp_sackdelay  = sp->sackdelay;
4965 		params.spp_pathmaxrxt = sp->pathmaxrxt;
4966 
4967 		/*draft-11 doesn't say what to return in spp_flags*/
4968 		params.spp_flags      = sp->param_flags;
4969 	}
4970 
4971 	if (copy_to_user(optval, &params, len))
4972 		return -EFAULT;
4973 
4974 	if (put_user(len, optlen))
4975 		return -EFAULT;
4976 
4977 	return 0;
4978 }
4979 
4980 /*
4981  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
4982  *
4983  * This option will effect the way delayed acks are performed.  This
4984  * option allows you to get or set the delayed ack time, in
4985  * milliseconds.  It also allows changing the delayed ack frequency.
4986  * Changing the frequency to 1 disables the delayed sack algorithm.  If
4987  * the assoc_id is 0, then this sets or gets the endpoints default
4988  * values.  If the assoc_id field is non-zero, then the set or get
4989  * effects the specified association for the one to many model (the
4990  * assoc_id field is ignored by the one to one model).  Note that if
4991  * sack_delay or sack_freq are 0 when setting this option, then the
4992  * current values will remain unchanged.
4993  *
4994  * struct sctp_sack_info {
4995  *     sctp_assoc_t            sack_assoc_id;
4996  *     uint32_t                sack_delay;
4997  *     uint32_t                sack_freq;
4998  * };
4999  *
5000  * sack_assoc_id -  This parameter, indicates which association the user
5001  *    is performing an action upon.  Note that if this field's value is
5002  *    zero then the endpoints default value is changed (effecting future
5003  *    associations only).
5004  *
5005  * sack_delay -  This parameter contains the number of milliseconds that
5006  *    the user is requesting the delayed ACK timer be set to.  Note that
5007  *    this value is defined in the standard to be between 200 and 500
5008  *    milliseconds.
5009  *
5010  * sack_freq -  This parameter contains the number of packets that must
5011  *    be received before a sack is sent without waiting for the delay
5012  *    timer to expire.  The default value for this is 2, setting this
5013  *    value to 1 will disable the delayed sack algorithm.
5014  */
5015 static int sctp_getsockopt_delayed_ack(struct sock *sk, int len,
5016 					    char __user *optval,
5017 					    int __user *optlen)
5018 {
5019 	struct sctp_sack_info    params;
5020 	struct sctp_association *asoc = NULL;
5021 	struct sctp_sock        *sp = sctp_sk(sk);
5022 
5023 	if (len >= sizeof(struct sctp_sack_info)) {
5024 		len = sizeof(struct sctp_sack_info);
5025 
5026 		if (copy_from_user(&params, optval, len))
5027 			return -EFAULT;
5028 	} else if (len == sizeof(struct sctp_assoc_value)) {
5029 		pr_warn_ratelimited(DEPRECATED
5030 				    "%s (pid %d) "
5031 				    "Use of struct sctp_assoc_value in delayed_ack socket option.\n"
5032 				    "Use struct sctp_sack_info instead\n",
5033 				    current->comm, task_pid_nr(current));
5034 		if (copy_from_user(&params, optval, len))
5035 			return -EFAULT;
5036 	} else
5037 		return -EINVAL;
5038 
5039 	/* Get association, if sack_assoc_id != 0 and the socket is a one
5040 	 * to many style socket, and an association was not found, then
5041 	 * the id was invalid.
5042 	 */
5043 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
5044 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
5045 		return -EINVAL;
5046 
5047 	if (asoc) {
5048 		/* Fetch association values. */
5049 		if (asoc->param_flags & SPP_SACKDELAY_ENABLE) {
5050 			params.sack_delay = jiffies_to_msecs(
5051 				asoc->sackdelay);
5052 			params.sack_freq = asoc->sackfreq;
5053 
5054 		} else {
5055 			params.sack_delay = 0;
5056 			params.sack_freq = 1;
5057 		}
5058 	} else {
5059 		/* Fetch socket values. */
5060 		if (sp->param_flags & SPP_SACKDELAY_ENABLE) {
5061 			params.sack_delay  = sp->sackdelay;
5062 			params.sack_freq = sp->sackfreq;
5063 		} else {
5064 			params.sack_delay  = 0;
5065 			params.sack_freq = 1;
5066 		}
5067 	}
5068 
5069 	if (copy_to_user(optval, &params, len))
5070 		return -EFAULT;
5071 
5072 	if (put_user(len, optlen))
5073 		return -EFAULT;
5074 
5075 	return 0;
5076 }
5077 
5078 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
5079  *
5080  * Applications can specify protocol parameters for the default association
5081  * initialization.  The option name argument to setsockopt() and getsockopt()
5082  * is SCTP_INITMSG.
5083  *
5084  * Setting initialization parameters is effective only on an unconnected
5085  * socket (for UDP-style sockets only future associations are effected
5086  * by the change).  With TCP-style sockets, this option is inherited by
5087  * sockets derived from a listener socket.
5088  */
5089 static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
5090 {
5091 	if (len < sizeof(struct sctp_initmsg))
5092 		return -EINVAL;
5093 	len = sizeof(struct sctp_initmsg);
5094 	if (put_user(len, optlen))
5095 		return -EFAULT;
5096 	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
5097 		return -EFAULT;
5098 	return 0;
5099 }
5100 
5101 
5102 static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
5103 				      char __user *optval, int __user *optlen)
5104 {
5105 	struct sctp_association *asoc;
5106 	int cnt = 0;
5107 	struct sctp_getaddrs getaddrs;
5108 	struct sctp_transport *from;
5109 	void __user *to;
5110 	union sctp_addr temp;
5111 	struct sctp_sock *sp = sctp_sk(sk);
5112 	int addrlen;
5113 	size_t space_left;
5114 	int bytes_copied;
5115 
5116 	if (len < sizeof(struct sctp_getaddrs))
5117 		return -EINVAL;
5118 
5119 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
5120 		return -EFAULT;
5121 
5122 	/* For UDP-style sockets, id specifies the association to query.  */
5123 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
5124 	if (!asoc)
5125 		return -EINVAL;
5126 
5127 	to = optval + offsetof(struct sctp_getaddrs, addrs);
5128 	space_left = len - offsetof(struct sctp_getaddrs, addrs);
5129 
5130 	list_for_each_entry(from, &asoc->peer.transport_addr_list,
5131 				transports) {
5132 		memcpy(&temp, &from->ipaddr, sizeof(temp));
5133 		addrlen = sctp_get_pf_specific(sk->sk_family)
5134 			      ->addr_to_user(sp, &temp);
5135 		if (space_left < addrlen)
5136 			return -ENOMEM;
5137 		if (copy_to_user(to, &temp, addrlen))
5138 			return -EFAULT;
5139 		to += addrlen;
5140 		cnt++;
5141 		space_left -= addrlen;
5142 	}
5143 
5144 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
5145 		return -EFAULT;
5146 	bytes_copied = ((char __user *)to) - optval;
5147 	if (put_user(bytes_copied, optlen))
5148 		return -EFAULT;
5149 
5150 	return 0;
5151 }
5152 
5153 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
5154 			    size_t space_left, int *bytes_copied)
5155 {
5156 	struct sctp_sockaddr_entry *addr;
5157 	union sctp_addr temp;
5158 	int cnt = 0;
5159 	int addrlen;
5160 	struct net *net = sock_net(sk);
5161 
5162 	rcu_read_lock();
5163 	list_for_each_entry_rcu(addr, &net->sctp.local_addr_list, list) {
5164 		if (!addr->valid)
5165 			continue;
5166 
5167 		if ((PF_INET == sk->sk_family) &&
5168 		    (AF_INET6 == addr->a.sa.sa_family))
5169 			continue;
5170 		if ((PF_INET6 == sk->sk_family) &&
5171 		    inet_v6_ipv6only(sk) &&
5172 		    (AF_INET == addr->a.sa.sa_family))
5173 			continue;
5174 		memcpy(&temp, &addr->a, sizeof(temp));
5175 		if (!temp.v4.sin_port)
5176 			temp.v4.sin_port = htons(port);
5177 
5178 		addrlen = sctp_get_pf_specific(sk->sk_family)
5179 			      ->addr_to_user(sctp_sk(sk), &temp);
5180 
5181 		if (space_left < addrlen) {
5182 			cnt =  -ENOMEM;
5183 			break;
5184 		}
5185 		memcpy(to, &temp, addrlen);
5186 
5187 		to += addrlen;
5188 		cnt++;
5189 		space_left -= addrlen;
5190 		*bytes_copied += addrlen;
5191 	}
5192 	rcu_read_unlock();
5193 
5194 	return cnt;
5195 }
5196 
5197 
5198 static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
5199 				       char __user *optval, int __user *optlen)
5200 {
5201 	struct sctp_bind_addr *bp;
5202 	struct sctp_association *asoc;
5203 	int cnt = 0;
5204 	struct sctp_getaddrs getaddrs;
5205 	struct sctp_sockaddr_entry *addr;
5206 	void __user *to;
5207 	union sctp_addr temp;
5208 	struct sctp_sock *sp = sctp_sk(sk);
5209 	int addrlen;
5210 	int err = 0;
5211 	size_t space_left;
5212 	int bytes_copied = 0;
5213 	void *addrs;
5214 	void *buf;
5215 
5216 	if (len < sizeof(struct sctp_getaddrs))
5217 		return -EINVAL;
5218 
5219 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
5220 		return -EFAULT;
5221 
5222 	/*
5223 	 *  For UDP-style sockets, id specifies the association to query.
5224 	 *  If the id field is set to the value '0' then the locally bound
5225 	 *  addresses are returned without regard to any particular
5226 	 *  association.
5227 	 */
5228 	if (0 == getaddrs.assoc_id) {
5229 		bp = &sctp_sk(sk)->ep->base.bind_addr;
5230 	} else {
5231 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
5232 		if (!asoc)
5233 			return -EINVAL;
5234 		bp = &asoc->base.bind_addr;
5235 	}
5236 
5237 	to = optval + offsetof(struct sctp_getaddrs, addrs);
5238 	space_left = len - offsetof(struct sctp_getaddrs, addrs);
5239 
5240 	addrs = kmalloc(space_left, GFP_USER | __GFP_NOWARN);
5241 	if (!addrs)
5242 		return -ENOMEM;
5243 
5244 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
5245 	 * addresses from the global local address list.
5246 	 */
5247 	if (sctp_list_single_entry(&bp->address_list)) {
5248 		addr = list_entry(bp->address_list.next,
5249 				  struct sctp_sockaddr_entry, list);
5250 		if (sctp_is_any(sk, &addr->a)) {
5251 			cnt = sctp_copy_laddrs(sk, bp->port, addrs,
5252 						space_left, &bytes_copied);
5253 			if (cnt < 0) {
5254 				err = cnt;
5255 				goto out;
5256 			}
5257 			goto copy_getaddrs;
5258 		}
5259 	}
5260 
5261 	buf = addrs;
5262 	/* Protection on the bound address list is not needed since
5263 	 * in the socket option context we hold a socket lock and
5264 	 * thus the bound address list can't change.
5265 	 */
5266 	list_for_each_entry(addr, &bp->address_list, list) {
5267 		memcpy(&temp, &addr->a, sizeof(temp));
5268 		addrlen = sctp_get_pf_specific(sk->sk_family)
5269 			      ->addr_to_user(sp, &temp);
5270 		if (space_left < addrlen) {
5271 			err =  -ENOMEM; /*fixme: right error?*/
5272 			goto out;
5273 		}
5274 		memcpy(buf, &temp, addrlen);
5275 		buf += addrlen;
5276 		bytes_copied += addrlen;
5277 		cnt++;
5278 		space_left -= addrlen;
5279 	}
5280 
5281 copy_getaddrs:
5282 	if (copy_to_user(to, addrs, bytes_copied)) {
5283 		err = -EFAULT;
5284 		goto out;
5285 	}
5286 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num)) {
5287 		err = -EFAULT;
5288 		goto out;
5289 	}
5290 	if (put_user(bytes_copied, optlen))
5291 		err = -EFAULT;
5292 out:
5293 	kfree(addrs);
5294 	return err;
5295 }
5296 
5297 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
5298  *
5299  * Requests that the local SCTP stack use the enclosed peer address as
5300  * the association primary.  The enclosed address must be one of the
5301  * association peer's addresses.
5302  */
5303 static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
5304 					char __user *optval, int __user *optlen)
5305 {
5306 	struct sctp_prim prim;
5307 	struct sctp_association *asoc;
5308 	struct sctp_sock *sp = sctp_sk(sk);
5309 
5310 	if (len < sizeof(struct sctp_prim))
5311 		return -EINVAL;
5312 
5313 	len = sizeof(struct sctp_prim);
5314 
5315 	if (copy_from_user(&prim, optval, len))
5316 		return -EFAULT;
5317 
5318 	asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
5319 	if (!asoc)
5320 		return -EINVAL;
5321 
5322 	if (!asoc->peer.primary_path)
5323 		return -ENOTCONN;
5324 
5325 	memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
5326 		asoc->peer.primary_path->af_specific->sockaddr_len);
5327 
5328 	sctp_get_pf_specific(sk->sk_family)->addr_to_user(sp,
5329 			(union sctp_addr *)&prim.ssp_addr);
5330 
5331 	if (put_user(len, optlen))
5332 		return -EFAULT;
5333 	if (copy_to_user(optval, &prim, len))
5334 		return -EFAULT;
5335 
5336 	return 0;
5337 }
5338 
5339 /*
5340  * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
5341  *
5342  * Requests that the local endpoint set the specified Adaptation Layer
5343  * Indication parameter for all future INIT and INIT-ACK exchanges.
5344  */
5345 static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
5346 				  char __user *optval, int __user *optlen)
5347 {
5348 	struct sctp_setadaptation adaptation;
5349 
5350 	if (len < sizeof(struct sctp_setadaptation))
5351 		return -EINVAL;
5352 
5353 	len = sizeof(struct sctp_setadaptation);
5354 
5355 	adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
5356 
5357 	if (put_user(len, optlen))
5358 		return -EFAULT;
5359 	if (copy_to_user(optval, &adaptation, len))
5360 		return -EFAULT;
5361 
5362 	return 0;
5363 }
5364 
5365 /*
5366  *
5367  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
5368  *
5369  *   Applications that wish to use the sendto() system call may wish to
5370  *   specify a default set of parameters that would normally be supplied
5371  *   through the inclusion of ancillary data.  This socket option allows
5372  *   such an application to set the default sctp_sndrcvinfo structure.
5373 
5374 
5375  *   The application that wishes to use this socket option simply passes
5376  *   in to this call the sctp_sndrcvinfo structure defined in Section
5377  *   5.2.2) The input parameters accepted by this call include
5378  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
5379  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
5380  *   to this call if the caller is using the UDP model.
5381  *
5382  *   For getsockopt, it get the default sctp_sndrcvinfo structure.
5383  */
5384 static int sctp_getsockopt_default_send_param(struct sock *sk,
5385 					int len, char __user *optval,
5386 					int __user *optlen)
5387 {
5388 	struct sctp_sock *sp = sctp_sk(sk);
5389 	struct sctp_association *asoc;
5390 	struct sctp_sndrcvinfo info;
5391 
5392 	if (len < sizeof(info))
5393 		return -EINVAL;
5394 
5395 	len = sizeof(info);
5396 
5397 	if (copy_from_user(&info, optval, len))
5398 		return -EFAULT;
5399 
5400 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
5401 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
5402 		return -EINVAL;
5403 	if (asoc) {
5404 		info.sinfo_stream = asoc->default_stream;
5405 		info.sinfo_flags = asoc->default_flags;
5406 		info.sinfo_ppid = asoc->default_ppid;
5407 		info.sinfo_context = asoc->default_context;
5408 		info.sinfo_timetolive = asoc->default_timetolive;
5409 	} else {
5410 		info.sinfo_stream = sp->default_stream;
5411 		info.sinfo_flags = sp->default_flags;
5412 		info.sinfo_ppid = sp->default_ppid;
5413 		info.sinfo_context = sp->default_context;
5414 		info.sinfo_timetolive = sp->default_timetolive;
5415 	}
5416 
5417 	if (put_user(len, optlen))
5418 		return -EFAULT;
5419 	if (copy_to_user(optval, &info, len))
5420 		return -EFAULT;
5421 
5422 	return 0;
5423 }
5424 
5425 /* RFC6458, Section 8.1.31. Set/get Default Send Parameters
5426  * (SCTP_DEFAULT_SNDINFO)
5427  */
5428 static int sctp_getsockopt_default_sndinfo(struct sock *sk, int len,
5429 					   char __user *optval,
5430 					   int __user *optlen)
5431 {
5432 	struct sctp_sock *sp = sctp_sk(sk);
5433 	struct sctp_association *asoc;
5434 	struct sctp_sndinfo info;
5435 
5436 	if (len < sizeof(info))
5437 		return -EINVAL;
5438 
5439 	len = sizeof(info);
5440 
5441 	if (copy_from_user(&info, optval, len))
5442 		return -EFAULT;
5443 
5444 	asoc = sctp_id2assoc(sk, info.snd_assoc_id);
5445 	if (!asoc && info.snd_assoc_id && sctp_style(sk, UDP))
5446 		return -EINVAL;
5447 	if (asoc) {
5448 		info.snd_sid = asoc->default_stream;
5449 		info.snd_flags = asoc->default_flags;
5450 		info.snd_ppid = asoc->default_ppid;
5451 		info.snd_context = asoc->default_context;
5452 	} else {
5453 		info.snd_sid = sp->default_stream;
5454 		info.snd_flags = sp->default_flags;
5455 		info.snd_ppid = sp->default_ppid;
5456 		info.snd_context = sp->default_context;
5457 	}
5458 
5459 	if (put_user(len, optlen))
5460 		return -EFAULT;
5461 	if (copy_to_user(optval, &info, len))
5462 		return -EFAULT;
5463 
5464 	return 0;
5465 }
5466 
5467 /*
5468  *
5469  * 7.1.5 SCTP_NODELAY
5470  *
5471  * Turn on/off any Nagle-like algorithm.  This means that packets are
5472  * generally sent as soon as possible and no unnecessary delays are
5473  * introduced, at the cost of more packets in the network.  Expects an
5474  * integer boolean flag.
5475  */
5476 
5477 static int sctp_getsockopt_nodelay(struct sock *sk, int len,
5478 				   char __user *optval, int __user *optlen)
5479 {
5480 	int val;
5481 
5482 	if (len < sizeof(int))
5483 		return -EINVAL;
5484 
5485 	len = sizeof(int);
5486 	val = (sctp_sk(sk)->nodelay == 1);
5487 	if (put_user(len, optlen))
5488 		return -EFAULT;
5489 	if (copy_to_user(optval, &val, len))
5490 		return -EFAULT;
5491 	return 0;
5492 }
5493 
5494 /*
5495  *
5496  * 7.1.1 SCTP_RTOINFO
5497  *
5498  * The protocol parameters used to initialize and bound retransmission
5499  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
5500  * and modify these parameters.
5501  * All parameters are time values, in milliseconds.  A value of 0, when
5502  * modifying the parameters, indicates that the current value should not
5503  * be changed.
5504  *
5505  */
5506 static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
5507 				char __user *optval,
5508 				int __user *optlen) {
5509 	struct sctp_rtoinfo rtoinfo;
5510 	struct sctp_association *asoc;
5511 
5512 	if (len < sizeof (struct sctp_rtoinfo))
5513 		return -EINVAL;
5514 
5515 	len = sizeof(struct sctp_rtoinfo);
5516 
5517 	if (copy_from_user(&rtoinfo, optval, len))
5518 		return -EFAULT;
5519 
5520 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
5521 
5522 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
5523 		return -EINVAL;
5524 
5525 	/* Values corresponding to the specific association. */
5526 	if (asoc) {
5527 		rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
5528 		rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
5529 		rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
5530 	} else {
5531 		/* Values corresponding to the endpoint. */
5532 		struct sctp_sock *sp = sctp_sk(sk);
5533 
5534 		rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
5535 		rtoinfo.srto_max = sp->rtoinfo.srto_max;
5536 		rtoinfo.srto_min = sp->rtoinfo.srto_min;
5537 	}
5538 
5539 	if (put_user(len, optlen))
5540 		return -EFAULT;
5541 
5542 	if (copy_to_user(optval, &rtoinfo, len))
5543 		return -EFAULT;
5544 
5545 	return 0;
5546 }
5547 
5548 /*
5549  *
5550  * 7.1.2 SCTP_ASSOCINFO
5551  *
5552  * This option is used to tune the maximum retransmission attempts
5553  * of the association.
5554  * Returns an error if the new association retransmission value is
5555  * greater than the sum of the retransmission value  of the peer.
5556  * See [SCTP] for more information.
5557  *
5558  */
5559 static int sctp_getsockopt_associnfo(struct sock *sk, int len,
5560 				     char __user *optval,
5561 				     int __user *optlen)
5562 {
5563 
5564 	struct sctp_assocparams assocparams;
5565 	struct sctp_association *asoc;
5566 	struct list_head *pos;
5567 	int cnt = 0;
5568 
5569 	if (len < sizeof (struct sctp_assocparams))
5570 		return -EINVAL;
5571 
5572 	len = sizeof(struct sctp_assocparams);
5573 
5574 	if (copy_from_user(&assocparams, optval, len))
5575 		return -EFAULT;
5576 
5577 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
5578 
5579 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
5580 		return -EINVAL;
5581 
5582 	/* Values correspoinding to the specific association */
5583 	if (asoc) {
5584 		assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
5585 		assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
5586 		assocparams.sasoc_local_rwnd = asoc->a_rwnd;
5587 		assocparams.sasoc_cookie_life = ktime_to_ms(asoc->cookie_life);
5588 
5589 		list_for_each(pos, &asoc->peer.transport_addr_list) {
5590 			cnt++;
5591 		}
5592 
5593 		assocparams.sasoc_number_peer_destinations = cnt;
5594 	} else {
5595 		/* Values corresponding to the endpoint */
5596 		struct sctp_sock *sp = sctp_sk(sk);
5597 
5598 		assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
5599 		assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
5600 		assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
5601 		assocparams.sasoc_cookie_life =
5602 					sp->assocparams.sasoc_cookie_life;
5603 		assocparams.sasoc_number_peer_destinations =
5604 					sp->assocparams.
5605 					sasoc_number_peer_destinations;
5606 	}
5607 
5608 	if (put_user(len, optlen))
5609 		return -EFAULT;
5610 
5611 	if (copy_to_user(optval, &assocparams, len))
5612 		return -EFAULT;
5613 
5614 	return 0;
5615 }
5616 
5617 /*
5618  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
5619  *
5620  * This socket option is a boolean flag which turns on or off mapped V4
5621  * addresses.  If this option is turned on and the socket is type
5622  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
5623  * If this option is turned off, then no mapping will be done of V4
5624  * addresses and a user will receive both PF_INET6 and PF_INET type
5625  * addresses on the socket.
5626  */
5627 static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
5628 				    char __user *optval, int __user *optlen)
5629 {
5630 	int val;
5631 	struct sctp_sock *sp = sctp_sk(sk);
5632 
5633 	if (len < sizeof(int))
5634 		return -EINVAL;
5635 
5636 	len = sizeof(int);
5637 	val = sp->v4mapped;
5638 	if (put_user(len, optlen))
5639 		return -EFAULT;
5640 	if (copy_to_user(optval, &val, len))
5641 		return -EFAULT;
5642 
5643 	return 0;
5644 }
5645 
5646 /*
5647  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
5648  * (chapter and verse is quoted at sctp_setsockopt_context())
5649  */
5650 static int sctp_getsockopt_context(struct sock *sk, int len,
5651 				   char __user *optval, int __user *optlen)
5652 {
5653 	struct sctp_assoc_value params;
5654 	struct sctp_sock *sp;
5655 	struct sctp_association *asoc;
5656 
5657 	if (len < sizeof(struct sctp_assoc_value))
5658 		return -EINVAL;
5659 
5660 	len = sizeof(struct sctp_assoc_value);
5661 
5662 	if (copy_from_user(&params, optval, len))
5663 		return -EFAULT;
5664 
5665 	sp = sctp_sk(sk);
5666 
5667 	if (params.assoc_id != 0) {
5668 		asoc = sctp_id2assoc(sk, params.assoc_id);
5669 		if (!asoc)
5670 			return -EINVAL;
5671 		params.assoc_value = asoc->default_rcv_context;
5672 	} else {
5673 		params.assoc_value = sp->default_rcv_context;
5674 	}
5675 
5676 	if (put_user(len, optlen))
5677 		return -EFAULT;
5678 	if (copy_to_user(optval, &params, len))
5679 		return -EFAULT;
5680 
5681 	return 0;
5682 }
5683 
5684 /*
5685  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
5686  * This option will get or set the maximum size to put in any outgoing
5687  * SCTP DATA chunk.  If a message is larger than this size it will be
5688  * fragmented by SCTP into the specified size.  Note that the underlying
5689  * SCTP implementation may fragment into smaller sized chunks when the
5690  * PMTU of the underlying association is smaller than the value set by
5691  * the user.  The default value for this option is '0' which indicates
5692  * the user is NOT limiting fragmentation and only the PMTU will effect
5693  * SCTP's choice of DATA chunk size.  Note also that values set larger
5694  * than the maximum size of an IP datagram will effectively let SCTP
5695  * control fragmentation (i.e. the same as setting this option to 0).
5696  *
5697  * The following structure is used to access and modify this parameter:
5698  *
5699  * struct sctp_assoc_value {
5700  *   sctp_assoc_t assoc_id;
5701  *   uint32_t assoc_value;
5702  * };
5703  *
5704  * assoc_id:  This parameter is ignored for one-to-one style sockets.
5705  *    For one-to-many style sockets this parameter indicates which
5706  *    association the user is performing an action upon.  Note that if
5707  *    this field's value is zero then the endpoints default value is
5708  *    changed (effecting future associations only).
5709  * assoc_value:  This parameter specifies the maximum size in bytes.
5710  */
5711 static int sctp_getsockopt_maxseg(struct sock *sk, int len,
5712 				  char __user *optval, int __user *optlen)
5713 {
5714 	struct sctp_assoc_value params;
5715 	struct sctp_association *asoc;
5716 
5717 	if (len == sizeof(int)) {
5718 		pr_warn_ratelimited(DEPRECATED
5719 				    "%s (pid %d) "
5720 				    "Use of int in maxseg socket option.\n"
5721 				    "Use struct sctp_assoc_value instead\n",
5722 				    current->comm, task_pid_nr(current));
5723 		params.assoc_id = 0;
5724 	} else if (len >= sizeof(struct sctp_assoc_value)) {
5725 		len = sizeof(struct sctp_assoc_value);
5726 		if (copy_from_user(&params, optval, sizeof(params)))
5727 			return -EFAULT;
5728 	} else
5729 		return -EINVAL;
5730 
5731 	asoc = sctp_id2assoc(sk, params.assoc_id);
5732 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
5733 		return -EINVAL;
5734 
5735 	if (asoc)
5736 		params.assoc_value = asoc->frag_point;
5737 	else
5738 		params.assoc_value = sctp_sk(sk)->user_frag;
5739 
5740 	if (put_user(len, optlen))
5741 		return -EFAULT;
5742 	if (len == sizeof(int)) {
5743 		if (copy_to_user(optval, &params.assoc_value, len))
5744 			return -EFAULT;
5745 	} else {
5746 		if (copy_to_user(optval, &params, len))
5747 			return -EFAULT;
5748 	}
5749 
5750 	return 0;
5751 }
5752 
5753 /*
5754  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
5755  * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
5756  */
5757 static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
5758 					       char __user *optval, int __user *optlen)
5759 {
5760 	int val;
5761 
5762 	if (len < sizeof(int))
5763 		return -EINVAL;
5764 
5765 	len = sizeof(int);
5766 
5767 	val = sctp_sk(sk)->frag_interleave;
5768 	if (put_user(len, optlen))
5769 		return -EFAULT;
5770 	if (copy_to_user(optval, &val, len))
5771 		return -EFAULT;
5772 
5773 	return 0;
5774 }
5775 
5776 /*
5777  * 7.1.25.  Set or Get the sctp partial delivery point
5778  * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
5779  */
5780 static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
5781 						  char __user *optval,
5782 						  int __user *optlen)
5783 {
5784 	u32 val;
5785 
5786 	if (len < sizeof(u32))
5787 		return -EINVAL;
5788 
5789 	len = sizeof(u32);
5790 
5791 	val = sctp_sk(sk)->pd_point;
5792 	if (put_user(len, optlen))
5793 		return -EFAULT;
5794 	if (copy_to_user(optval, &val, len))
5795 		return -EFAULT;
5796 
5797 	return 0;
5798 }
5799 
5800 /*
5801  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
5802  * (chapter and verse is quoted at sctp_setsockopt_maxburst())
5803  */
5804 static int sctp_getsockopt_maxburst(struct sock *sk, int len,
5805 				    char __user *optval,
5806 				    int __user *optlen)
5807 {
5808 	struct sctp_assoc_value params;
5809 	struct sctp_sock *sp;
5810 	struct sctp_association *asoc;
5811 
5812 	if (len == sizeof(int)) {
5813 		pr_warn_ratelimited(DEPRECATED
5814 				    "%s (pid %d) "
5815 				    "Use of int in max_burst socket option.\n"
5816 				    "Use struct sctp_assoc_value instead\n",
5817 				    current->comm, task_pid_nr(current));
5818 		params.assoc_id = 0;
5819 	} else if (len >= sizeof(struct sctp_assoc_value)) {
5820 		len = sizeof(struct sctp_assoc_value);
5821 		if (copy_from_user(&params, optval, len))
5822 			return -EFAULT;
5823 	} else
5824 		return -EINVAL;
5825 
5826 	sp = sctp_sk(sk);
5827 
5828 	if (params.assoc_id != 0) {
5829 		asoc = sctp_id2assoc(sk, params.assoc_id);
5830 		if (!asoc)
5831 			return -EINVAL;
5832 		params.assoc_value = asoc->max_burst;
5833 	} else
5834 		params.assoc_value = sp->max_burst;
5835 
5836 	if (len == sizeof(int)) {
5837 		if (copy_to_user(optval, &params.assoc_value, len))
5838 			return -EFAULT;
5839 	} else {
5840 		if (copy_to_user(optval, &params, len))
5841 			return -EFAULT;
5842 	}
5843 
5844 	return 0;
5845 
5846 }
5847 
5848 static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
5849 				    char __user *optval, int __user *optlen)
5850 {
5851 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5852 	struct sctp_hmacalgo  __user *p = (void __user *)optval;
5853 	struct sctp_hmac_algo_param *hmacs;
5854 	__u16 data_len = 0;
5855 	u32 num_idents;
5856 	int i;
5857 
5858 	if (!ep->auth_enable)
5859 		return -EACCES;
5860 
5861 	hmacs = ep->auth_hmacs_list;
5862 	data_len = ntohs(hmacs->param_hdr.length) - sizeof(sctp_paramhdr_t);
5863 
5864 	if (len < sizeof(struct sctp_hmacalgo) + data_len)
5865 		return -EINVAL;
5866 
5867 	len = sizeof(struct sctp_hmacalgo) + data_len;
5868 	num_idents = data_len / sizeof(u16);
5869 
5870 	if (put_user(len, optlen))
5871 		return -EFAULT;
5872 	if (put_user(num_idents, &p->shmac_num_idents))
5873 		return -EFAULT;
5874 	for (i = 0; i < num_idents; i++) {
5875 		__u16 hmacid = ntohs(hmacs->hmac_ids[i]);
5876 
5877 		if (copy_to_user(&p->shmac_idents[i], &hmacid, sizeof(__u16)))
5878 			return -EFAULT;
5879 	}
5880 	return 0;
5881 }
5882 
5883 static int sctp_getsockopt_active_key(struct sock *sk, int len,
5884 				    char __user *optval, int __user *optlen)
5885 {
5886 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5887 	struct sctp_authkeyid val;
5888 	struct sctp_association *asoc;
5889 
5890 	if (!ep->auth_enable)
5891 		return -EACCES;
5892 
5893 	if (len < sizeof(struct sctp_authkeyid))
5894 		return -EINVAL;
5895 	if (copy_from_user(&val, optval, sizeof(struct sctp_authkeyid)))
5896 		return -EFAULT;
5897 
5898 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
5899 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
5900 		return -EINVAL;
5901 
5902 	if (asoc)
5903 		val.scact_keynumber = asoc->active_key_id;
5904 	else
5905 		val.scact_keynumber = ep->active_key_id;
5906 
5907 	len = sizeof(struct sctp_authkeyid);
5908 	if (put_user(len, optlen))
5909 		return -EFAULT;
5910 	if (copy_to_user(optval, &val, len))
5911 		return -EFAULT;
5912 
5913 	return 0;
5914 }
5915 
5916 static int sctp_getsockopt_peer_auth_chunks(struct sock *sk, int len,
5917 				    char __user *optval, int __user *optlen)
5918 {
5919 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5920 	struct sctp_authchunks __user *p = (void __user *)optval;
5921 	struct sctp_authchunks val;
5922 	struct sctp_association *asoc;
5923 	struct sctp_chunks_param *ch;
5924 	u32    num_chunks = 0;
5925 	char __user *to;
5926 
5927 	if (!ep->auth_enable)
5928 		return -EACCES;
5929 
5930 	if (len < sizeof(struct sctp_authchunks))
5931 		return -EINVAL;
5932 
5933 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5934 		return -EFAULT;
5935 
5936 	to = p->gauth_chunks;
5937 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5938 	if (!asoc)
5939 		return -EINVAL;
5940 
5941 	ch = asoc->peer.peer_chunks;
5942 	if (!ch)
5943 		goto num;
5944 
5945 	/* See if the user provided enough room for all the data */
5946 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5947 	if (len < num_chunks)
5948 		return -EINVAL;
5949 
5950 	if (copy_to_user(to, ch->chunks, num_chunks))
5951 		return -EFAULT;
5952 num:
5953 	len = sizeof(struct sctp_authchunks) + num_chunks;
5954 	if (put_user(len, optlen))
5955 		return -EFAULT;
5956 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
5957 		return -EFAULT;
5958 	return 0;
5959 }
5960 
5961 static int sctp_getsockopt_local_auth_chunks(struct sock *sk, int len,
5962 				    char __user *optval, int __user *optlen)
5963 {
5964 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5965 	struct sctp_authchunks __user *p = (void __user *)optval;
5966 	struct sctp_authchunks val;
5967 	struct sctp_association *asoc;
5968 	struct sctp_chunks_param *ch;
5969 	u32    num_chunks = 0;
5970 	char __user *to;
5971 
5972 	if (!ep->auth_enable)
5973 		return -EACCES;
5974 
5975 	if (len < sizeof(struct sctp_authchunks))
5976 		return -EINVAL;
5977 
5978 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5979 		return -EFAULT;
5980 
5981 	to = p->gauth_chunks;
5982 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5983 	if (!asoc && val.gauth_assoc_id && sctp_style(sk, UDP))
5984 		return -EINVAL;
5985 
5986 	if (asoc)
5987 		ch = (struct sctp_chunks_param *)asoc->c.auth_chunks;
5988 	else
5989 		ch = ep->auth_chunk_list;
5990 
5991 	if (!ch)
5992 		goto num;
5993 
5994 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5995 	if (len < sizeof(struct sctp_authchunks) + num_chunks)
5996 		return -EINVAL;
5997 
5998 	if (copy_to_user(to, ch->chunks, num_chunks))
5999 		return -EFAULT;
6000 num:
6001 	len = sizeof(struct sctp_authchunks) + num_chunks;
6002 	if (put_user(len, optlen))
6003 		return -EFAULT;
6004 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
6005 		return -EFAULT;
6006 
6007 	return 0;
6008 }
6009 
6010 /*
6011  * 8.2.5.  Get the Current Number of Associations (SCTP_GET_ASSOC_NUMBER)
6012  * This option gets the current number of associations that are attached
6013  * to a one-to-many style socket.  The option value is an uint32_t.
6014  */
6015 static int sctp_getsockopt_assoc_number(struct sock *sk, int len,
6016 				    char __user *optval, int __user *optlen)
6017 {
6018 	struct sctp_sock *sp = sctp_sk(sk);
6019 	struct sctp_association *asoc;
6020 	u32 val = 0;
6021 
6022 	if (sctp_style(sk, TCP))
6023 		return -EOPNOTSUPP;
6024 
6025 	if (len < sizeof(u32))
6026 		return -EINVAL;
6027 
6028 	len = sizeof(u32);
6029 
6030 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
6031 		val++;
6032 	}
6033 
6034 	if (put_user(len, optlen))
6035 		return -EFAULT;
6036 	if (copy_to_user(optval, &val, len))
6037 		return -EFAULT;
6038 
6039 	return 0;
6040 }
6041 
6042 /*
6043  * 8.1.23 SCTP_AUTO_ASCONF
6044  * See the corresponding setsockopt entry as description
6045  */
6046 static int sctp_getsockopt_auto_asconf(struct sock *sk, int len,
6047 				   char __user *optval, int __user *optlen)
6048 {
6049 	int val = 0;
6050 
6051 	if (len < sizeof(int))
6052 		return -EINVAL;
6053 
6054 	len = sizeof(int);
6055 	if (sctp_sk(sk)->do_auto_asconf && sctp_is_ep_boundall(sk))
6056 		val = 1;
6057 	if (put_user(len, optlen))
6058 		return -EFAULT;
6059 	if (copy_to_user(optval, &val, len))
6060 		return -EFAULT;
6061 	return 0;
6062 }
6063 
6064 /*
6065  * 8.2.6. Get the Current Identifiers of Associations
6066  *        (SCTP_GET_ASSOC_ID_LIST)
6067  *
6068  * This option gets the current list of SCTP association identifiers of
6069  * the SCTP associations handled by a one-to-many style socket.
6070  */
6071 static int sctp_getsockopt_assoc_ids(struct sock *sk, int len,
6072 				    char __user *optval, int __user *optlen)
6073 {
6074 	struct sctp_sock *sp = sctp_sk(sk);
6075 	struct sctp_association *asoc;
6076 	struct sctp_assoc_ids *ids;
6077 	u32 num = 0;
6078 
6079 	if (sctp_style(sk, TCP))
6080 		return -EOPNOTSUPP;
6081 
6082 	if (len < sizeof(struct sctp_assoc_ids))
6083 		return -EINVAL;
6084 
6085 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
6086 		num++;
6087 	}
6088 
6089 	if (len < sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num)
6090 		return -EINVAL;
6091 
6092 	len = sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num;
6093 
6094 	ids = kmalloc(len, GFP_USER | __GFP_NOWARN);
6095 	if (unlikely(!ids))
6096 		return -ENOMEM;
6097 
6098 	ids->gaids_number_of_ids = num;
6099 	num = 0;
6100 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
6101 		ids->gaids_assoc_id[num++] = asoc->assoc_id;
6102 	}
6103 
6104 	if (put_user(len, optlen) || copy_to_user(optval, ids, len)) {
6105 		kfree(ids);
6106 		return -EFAULT;
6107 	}
6108 
6109 	kfree(ids);
6110 	return 0;
6111 }
6112 
6113 /*
6114  * SCTP_PEER_ADDR_THLDS
6115  *
6116  * This option allows us to fetch the partially failed threshold for one or all
6117  * transports in an association.  See Section 6.1 of:
6118  * http://www.ietf.org/id/draft-nishida-tsvwg-sctp-failover-05.txt
6119  */
6120 static int sctp_getsockopt_paddr_thresholds(struct sock *sk,
6121 					    char __user *optval,
6122 					    int len,
6123 					    int __user *optlen)
6124 {
6125 	struct sctp_paddrthlds val;
6126 	struct sctp_transport *trans;
6127 	struct sctp_association *asoc;
6128 
6129 	if (len < sizeof(struct sctp_paddrthlds))
6130 		return -EINVAL;
6131 	len = sizeof(struct sctp_paddrthlds);
6132 	if (copy_from_user(&val, (struct sctp_paddrthlds __user *)optval, len))
6133 		return -EFAULT;
6134 
6135 	if (sctp_is_any(sk, (const union sctp_addr *)&val.spt_address)) {
6136 		asoc = sctp_id2assoc(sk, val.spt_assoc_id);
6137 		if (!asoc)
6138 			return -ENOENT;
6139 
6140 		val.spt_pathpfthld = asoc->pf_retrans;
6141 		val.spt_pathmaxrxt = asoc->pathmaxrxt;
6142 	} else {
6143 		trans = sctp_addr_id2transport(sk, &val.spt_address,
6144 					       val.spt_assoc_id);
6145 		if (!trans)
6146 			return -ENOENT;
6147 
6148 		val.spt_pathmaxrxt = trans->pathmaxrxt;
6149 		val.spt_pathpfthld = trans->pf_retrans;
6150 	}
6151 
6152 	if (put_user(len, optlen) || copy_to_user(optval, &val, len))
6153 		return -EFAULT;
6154 
6155 	return 0;
6156 }
6157 
6158 /*
6159  * SCTP_GET_ASSOC_STATS
6160  *
6161  * This option retrieves local per endpoint statistics. It is modeled
6162  * after OpenSolaris' implementation
6163  */
6164 static int sctp_getsockopt_assoc_stats(struct sock *sk, int len,
6165 				       char __user *optval,
6166 				       int __user *optlen)
6167 {
6168 	struct sctp_assoc_stats sas;
6169 	struct sctp_association *asoc = NULL;
6170 
6171 	/* User must provide at least the assoc id */
6172 	if (len < sizeof(sctp_assoc_t))
6173 		return -EINVAL;
6174 
6175 	/* Allow the struct to grow and fill in as much as possible */
6176 	len = min_t(size_t, len, sizeof(sas));
6177 
6178 	if (copy_from_user(&sas, optval, len))
6179 		return -EFAULT;
6180 
6181 	asoc = sctp_id2assoc(sk, sas.sas_assoc_id);
6182 	if (!asoc)
6183 		return -EINVAL;
6184 
6185 	sas.sas_rtxchunks = asoc->stats.rtxchunks;
6186 	sas.sas_gapcnt = asoc->stats.gapcnt;
6187 	sas.sas_outofseqtsns = asoc->stats.outofseqtsns;
6188 	sas.sas_osacks = asoc->stats.osacks;
6189 	sas.sas_isacks = asoc->stats.isacks;
6190 	sas.sas_octrlchunks = asoc->stats.octrlchunks;
6191 	sas.sas_ictrlchunks = asoc->stats.ictrlchunks;
6192 	sas.sas_oodchunks = asoc->stats.oodchunks;
6193 	sas.sas_iodchunks = asoc->stats.iodchunks;
6194 	sas.sas_ouodchunks = asoc->stats.ouodchunks;
6195 	sas.sas_iuodchunks = asoc->stats.iuodchunks;
6196 	sas.sas_idupchunks = asoc->stats.idupchunks;
6197 	sas.sas_opackets = asoc->stats.opackets;
6198 	sas.sas_ipackets = asoc->stats.ipackets;
6199 
6200 	/* New high max rto observed, will return 0 if not a single
6201 	 * RTO update took place. obs_rto_ipaddr will be bogus
6202 	 * in such a case
6203 	 */
6204 	sas.sas_maxrto = asoc->stats.max_obs_rto;
6205 	memcpy(&sas.sas_obs_rto_ipaddr, &asoc->stats.obs_rto_ipaddr,
6206 		sizeof(struct sockaddr_storage));
6207 
6208 	/* Mark beginning of a new observation period */
6209 	asoc->stats.max_obs_rto = asoc->rto_min;
6210 
6211 	if (put_user(len, optlen))
6212 		return -EFAULT;
6213 
6214 	pr_debug("%s: len:%d, assoc_id:%d\n", __func__, len, sas.sas_assoc_id);
6215 
6216 	if (copy_to_user(optval, &sas, len))
6217 		return -EFAULT;
6218 
6219 	return 0;
6220 }
6221 
6222 static int sctp_getsockopt_recvrcvinfo(struct sock *sk,	int len,
6223 				       char __user *optval,
6224 				       int __user *optlen)
6225 {
6226 	int val = 0;
6227 
6228 	if (len < sizeof(int))
6229 		return -EINVAL;
6230 
6231 	len = sizeof(int);
6232 	if (sctp_sk(sk)->recvrcvinfo)
6233 		val = 1;
6234 	if (put_user(len, optlen))
6235 		return -EFAULT;
6236 	if (copy_to_user(optval, &val, len))
6237 		return -EFAULT;
6238 
6239 	return 0;
6240 }
6241 
6242 static int sctp_getsockopt_recvnxtinfo(struct sock *sk,	int len,
6243 				       char __user *optval,
6244 				       int __user *optlen)
6245 {
6246 	int val = 0;
6247 
6248 	if (len < sizeof(int))
6249 		return -EINVAL;
6250 
6251 	len = sizeof(int);
6252 	if (sctp_sk(sk)->recvnxtinfo)
6253 		val = 1;
6254 	if (put_user(len, optlen))
6255 		return -EFAULT;
6256 	if (copy_to_user(optval, &val, len))
6257 		return -EFAULT;
6258 
6259 	return 0;
6260 }
6261 
6262 static int sctp_getsockopt_pr_supported(struct sock *sk, int len,
6263 					char __user *optval,
6264 					int __user *optlen)
6265 {
6266 	struct sctp_assoc_value params;
6267 	struct sctp_association *asoc;
6268 	int retval = -EFAULT;
6269 
6270 	if (len < sizeof(params)) {
6271 		retval = -EINVAL;
6272 		goto out;
6273 	}
6274 
6275 	len = sizeof(params);
6276 	if (copy_from_user(&params, optval, len))
6277 		goto out;
6278 
6279 	asoc = sctp_id2assoc(sk, params.assoc_id);
6280 	if (asoc) {
6281 		params.assoc_value = asoc->prsctp_enable;
6282 	} else if (!params.assoc_id) {
6283 		struct sctp_sock *sp = sctp_sk(sk);
6284 
6285 		params.assoc_value = sp->ep->prsctp_enable;
6286 	} else {
6287 		retval = -EINVAL;
6288 		goto out;
6289 	}
6290 
6291 	if (put_user(len, optlen))
6292 		goto out;
6293 
6294 	if (copy_to_user(optval, &params, len))
6295 		goto out;
6296 
6297 	retval = 0;
6298 
6299 out:
6300 	return retval;
6301 }
6302 
6303 static int sctp_getsockopt_default_prinfo(struct sock *sk, int len,
6304 					  char __user *optval,
6305 					  int __user *optlen)
6306 {
6307 	struct sctp_default_prinfo info;
6308 	struct sctp_association *asoc;
6309 	int retval = -EFAULT;
6310 
6311 	if (len < sizeof(info)) {
6312 		retval = -EINVAL;
6313 		goto out;
6314 	}
6315 
6316 	len = sizeof(info);
6317 	if (copy_from_user(&info, optval, len))
6318 		goto out;
6319 
6320 	asoc = sctp_id2assoc(sk, info.pr_assoc_id);
6321 	if (asoc) {
6322 		info.pr_policy = SCTP_PR_POLICY(asoc->default_flags);
6323 		info.pr_value = asoc->default_timetolive;
6324 	} else if (!info.pr_assoc_id) {
6325 		struct sctp_sock *sp = sctp_sk(sk);
6326 
6327 		info.pr_policy = SCTP_PR_POLICY(sp->default_flags);
6328 		info.pr_value = sp->default_timetolive;
6329 	} else {
6330 		retval = -EINVAL;
6331 		goto out;
6332 	}
6333 
6334 	if (put_user(len, optlen))
6335 		goto out;
6336 
6337 	if (copy_to_user(optval, &info, len))
6338 		goto out;
6339 
6340 	retval = 0;
6341 
6342 out:
6343 	return retval;
6344 }
6345 
6346 static int sctp_getsockopt_pr_assocstatus(struct sock *sk, int len,
6347 					  char __user *optval,
6348 					  int __user *optlen)
6349 {
6350 	struct sctp_prstatus params;
6351 	struct sctp_association *asoc;
6352 	int policy;
6353 	int retval = -EINVAL;
6354 
6355 	if (len < sizeof(params))
6356 		goto out;
6357 
6358 	len = sizeof(params);
6359 	if (copy_from_user(&params, optval, len)) {
6360 		retval = -EFAULT;
6361 		goto out;
6362 	}
6363 
6364 	policy = params.sprstat_policy;
6365 	if (policy & ~SCTP_PR_SCTP_MASK)
6366 		goto out;
6367 
6368 	asoc = sctp_id2assoc(sk, params.sprstat_assoc_id);
6369 	if (!asoc)
6370 		goto out;
6371 
6372 	if (policy == SCTP_PR_SCTP_NONE) {
6373 		params.sprstat_abandoned_unsent = 0;
6374 		params.sprstat_abandoned_sent = 0;
6375 		for (policy = 0; policy <= SCTP_PR_INDEX(MAX); policy++) {
6376 			params.sprstat_abandoned_unsent +=
6377 				asoc->abandoned_unsent[policy];
6378 			params.sprstat_abandoned_sent +=
6379 				asoc->abandoned_sent[policy];
6380 		}
6381 	} else {
6382 		params.sprstat_abandoned_unsent =
6383 			asoc->abandoned_unsent[__SCTP_PR_INDEX(policy)];
6384 		params.sprstat_abandoned_sent =
6385 			asoc->abandoned_sent[__SCTP_PR_INDEX(policy)];
6386 	}
6387 
6388 	if (put_user(len, optlen)) {
6389 		retval = -EFAULT;
6390 		goto out;
6391 	}
6392 
6393 	if (copy_to_user(optval, &params, len)) {
6394 		retval = -EFAULT;
6395 		goto out;
6396 	}
6397 
6398 	retval = 0;
6399 
6400 out:
6401 	return retval;
6402 }
6403 
6404 static int sctp_getsockopt(struct sock *sk, int level, int optname,
6405 			   char __user *optval, int __user *optlen)
6406 {
6407 	int retval = 0;
6408 	int len;
6409 
6410 	pr_debug("%s: sk:%p, optname:%d\n", __func__, sk, optname);
6411 
6412 	/* I can hardly begin to describe how wrong this is.  This is
6413 	 * so broken as to be worse than useless.  The API draft
6414 	 * REALLY is NOT helpful here...  I am not convinced that the
6415 	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
6416 	 * are at all well-founded.
6417 	 */
6418 	if (level != SOL_SCTP) {
6419 		struct sctp_af *af = sctp_sk(sk)->pf->af;
6420 
6421 		retval = af->getsockopt(sk, level, optname, optval, optlen);
6422 		return retval;
6423 	}
6424 
6425 	if (get_user(len, optlen))
6426 		return -EFAULT;
6427 
6428 	if (len < 0)
6429 		return -EINVAL;
6430 
6431 	lock_sock(sk);
6432 
6433 	switch (optname) {
6434 	case SCTP_STATUS:
6435 		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
6436 		break;
6437 	case SCTP_DISABLE_FRAGMENTS:
6438 		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
6439 							   optlen);
6440 		break;
6441 	case SCTP_EVENTS:
6442 		retval = sctp_getsockopt_events(sk, len, optval, optlen);
6443 		break;
6444 	case SCTP_AUTOCLOSE:
6445 		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
6446 		break;
6447 	case SCTP_SOCKOPT_PEELOFF:
6448 		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
6449 		break;
6450 	case SCTP_PEER_ADDR_PARAMS:
6451 		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
6452 							  optlen);
6453 		break;
6454 	case SCTP_DELAYED_SACK:
6455 		retval = sctp_getsockopt_delayed_ack(sk, len, optval,
6456 							  optlen);
6457 		break;
6458 	case SCTP_INITMSG:
6459 		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
6460 		break;
6461 	case SCTP_GET_PEER_ADDRS:
6462 		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
6463 						    optlen);
6464 		break;
6465 	case SCTP_GET_LOCAL_ADDRS:
6466 		retval = sctp_getsockopt_local_addrs(sk, len, optval,
6467 						     optlen);
6468 		break;
6469 	case SCTP_SOCKOPT_CONNECTX3:
6470 		retval = sctp_getsockopt_connectx3(sk, len, optval, optlen);
6471 		break;
6472 	case SCTP_DEFAULT_SEND_PARAM:
6473 		retval = sctp_getsockopt_default_send_param(sk, len,
6474 							    optval, optlen);
6475 		break;
6476 	case SCTP_DEFAULT_SNDINFO:
6477 		retval = sctp_getsockopt_default_sndinfo(sk, len,
6478 							 optval, optlen);
6479 		break;
6480 	case SCTP_PRIMARY_ADDR:
6481 		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
6482 		break;
6483 	case SCTP_NODELAY:
6484 		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
6485 		break;
6486 	case SCTP_RTOINFO:
6487 		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
6488 		break;
6489 	case SCTP_ASSOCINFO:
6490 		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
6491 		break;
6492 	case SCTP_I_WANT_MAPPED_V4_ADDR:
6493 		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
6494 		break;
6495 	case SCTP_MAXSEG:
6496 		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
6497 		break;
6498 	case SCTP_GET_PEER_ADDR_INFO:
6499 		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
6500 							optlen);
6501 		break;
6502 	case SCTP_ADAPTATION_LAYER:
6503 		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
6504 							optlen);
6505 		break;
6506 	case SCTP_CONTEXT:
6507 		retval = sctp_getsockopt_context(sk, len, optval, optlen);
6508 		break;
6509 	case SCTP_FRAGMENT_INTERLEAVE:
6510 		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
6511 							     optlen);
6512 		break;
6513 	case SCTP_PARTIAL_DELIVERY_POINT:
6514 		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
6515 								optlen);
6516 		break;
6517 	case SCTP_MAX_BURST:
6518 		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
6519 		break;
6520 	case SCTP_AUTH_KEY:
6521 	case SCTP_AUTH_CHUNK:
6522 	case SCTP_AUTH_DELETE_KEY:
6523 		retval = -EOPNOTSUPP;
6524 		break;
6525 	case SCTP_HMAC_IDENT:
6526 		retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
6527 		break;
6528 	case SCTP_AUTH_ACTIVE_KEY:
6529 		retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
6530 		break;
6531 	case SCTP_PEER_AUTH_CHUNKS:
6532 		retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
6533 							optlen);
6534 		break;
6535 	case SCTP_LOCAL_AUTH_CHUNKS:
6536 		retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
6537 							optlen);
6538 		break;
6539 	case SCTP_GET_ASSOC_NUMBER:
6540 		retval = sctp_getsockopt_assoc_number(sk, len, optval, optlen);
6541 		break;
6542 	case SCTP_GET_ASSOC_ID_LIST:
6543 		retval = sctp_getsockopt_assoc_ids(sk, len, optval, optlen);
6544 		break;
6545 	case SCTP_AUTO_ASCONF:
6546 		retval = sctp_getsockopt_auto_asconf(sk, len, optval, optlen);
6547 		break;
6548 	case SCTP_PEER_ADDR_THLDS:
6549 		retval = sctp_getsockopt_paddr_thresholds(sk, optval, len, optlen);
6550 		break;
6551 	case SCTP_GET_ASSOC_STATS:
6552 		retval = sctp_getsockopt_assoc_stats(sk, len, optval, optlen);
6553 		break;
6554 	case SCTP_RECVRCVINFO:
6555 		retval = sctp_getsockopt_recvrcvinfo(sk, len, optval, optlen);
6556 		break;
6557 	case SCTP_RECVNXTINFO:
6558 		retval = sctp_getsockopt_recvnxtinfo(sk, len, optval, optlen);
6559 		break;
6560 	case SCTP_PR_SUPPORTED:
6561 		retval = sctp_getsockopt_pr_supported(sk, len, optval, optlen);
6562 		break;
6563 	case SCTP_DEFAULT_PRINFO:
6564 		retval = sctp_getsockopt_default_prinfo(sk, len, optval,
6565 							optlen);
6566 		break;
6567 	case SCTP_PR_ASSOC_STATUS:
6568 		retval = sctp_getsockopt_pr_assocstatus(sk, len, optval,
6569 							optlen);
6570 		break;
6571 	default:
6572 		retval = -ENOPROTOOPT;
6573 		break;
6574 	}
6575 
6576 	release_sock(sk);
6577 	return retval;
6578 }
6579 
6580 static int sctp_hash(struct sock *sk)
6581 {
6582 	/* STUB */
6583 	return 0;
6584 }
6585 
6586 static void sctp_unhash(struct sock *sk)
6587 {
6588 	/* STUB */
6589 }
6590 
6591 /* Check if port is acceptable.  Possibly find first available port.
6592  *
6593  * The port hash table (contained in the 'global' SCTP protocol storage
6594  * returned by struct sctp_protocol *sctp_get_protocol()). The hash
6595  * table is an array of 4096 lists (sctp_bind_hashbucket). Each
6596  * list (the list number is the port number hashed out, so as you
6597  * would expect from a hash function, all the ports in a given list have
6598  * such a number that hashes out to the same list number; you were
6599  * expecting that, right?); so each list has a set of ports, with a
6600  * link to the socket (struct sock) that uses it, the port number and
6601  * a fastreuse flag (FIXME: NPI ipg).
6602  */
6603 static struct sctp_bind_bucket *sctp_bucket_create(
6604 	struct sctp_bind_hashbucket *head, struct net *, unsigned short snum);
6605 
6606 static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
6607 {
6608 	struct sctp_bind_hashbucket *head; /* hash list */
6609 	struct sctp_bind_bucket *pp;
6610 	unsigned short snum;
6611 	int ret;
6612 
6613 	snum = ntohs(addr->v4.sin_port);
6614 
6615 	pr_debug("%s: begins, snum:%d\n", __func__, snum);
6616 
6617 	local_bh_disable();
6618 
6619 	if (snum == 0) {
6620 		/* Search for an available port. */
6621 		int low, high, remaining, index;
6622 		unsigned int rover;
6623 		struct net *net = sock_net(sk);
6624 
6625 		inet_get_local_port_range(net, &low, &high);
6626 		remaining = (high - low) + 1;
6627 		rover = prandom_u32() % remaining + low;
6628 
6629 		do {
6630 			rover++;
6631 			if ((rover < low) || (rover > high))
6632 				rover = low;
6633 			if (inet_is_local_reserved_port(net, rover))
6634 				continue;
6635 			index = sctp_phashfn(sock_net(sk), rover);
6636 			head = &sctp_port_hashtable[index];
6637 			spin_lock(&head->lock);
6638 			sctp_for_each_hentry(pp, &head->chain)
6639 				if ((pp->port == rover) &&
6640 				    net_eq(sock_net(sk), pp->net))
6641 					goto next;
6642 			break;
6643 		next:
6644 			spin_unlock(&head->lock);
6645 		} while (--remaining > 0);
6646 
6647 		/* Exhausted local port range during search? */
6648 		ret = 1;
6649 		if (remaining <= 0)
6650 			goto fail;
6651 
6652 		/* OK, here is the one we will use.  HEAD (the port
6653 		 * hash table list entry) is non-NULL and we hold it's
6654 		 * mutex.
6655 		 */
6656 		snum = rover;
6657 	} else {
6658 		/* We are given an specific port number; we verify
6659 		 * that it is not being used. If it is used, we will
6660 		 * exahust the search in the hash list corresponding
6661 		 * to the port number (snum) - we detect that with the
6662 		 * port iterator, pp being NULL.
6663 		 */
6664 		head = &sctp_port_hashtable[sctp_phashfn(sock_net(sk), snum)];
6665 		spin_lock(&head->lock);
6666 		sctp_for_each_hentry(pp, &head->chain) {
6667 			if ((pp->port == snum) && net_eq(pp->net, sock_net(sk)))
6668 				goto pp_found;
6669 		}
6670 	}
6671 	pp = NULL;
6672 	goto pp_not_found;
6673 pp_found:
6674 	if (!hlist_empty(&pp->owner)) {
6675 		/* We had a port hash table hit - there is an
6676 		 * available port (pp != NULL) and it is being
6677 		 * used by other socket (pp->owner not empty); that other
6678 		 * socket is going to be sk2.
6679 		 */
6680 		int reuse = sk->sk_reuse;
6681 		struct sock *sk2;
6682 
6683 		pr_debug("%s: found a possible match\n", __func__);
6684 
6685 		if (pp->fastreuse && sk->sk_reuse &&
6686 			sk->sk_state != SCTP_SS_LISTENING)
6687 			goto success;
6688 
6689 		/* Run through the list of sockets bound to the port
6690 		 * (pp->port) [via the pointers bind_next and
6691 		 * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
6692 		 * we get the endpoint they describe and run through
6693 		 * the endpoint's list of IP (v4 or v6) addresses,
6694 		 * comparing each of the addresses with the address of
6695 		 * the socket sk. If we find a match, then that means
6696 		 * that this port/socket (sk) combination are already
6697 		 * in an endpoint.
6698 		 */
6699 		sk_for_each_bound(sk2, &pp->owner) {
6700 			struct sctp_endpoint *ep2;
6701 			ep2 = sctp_sk(sk2)->ep;
6702 
6703 			if (sk == sk2 ||
6704 			    (reuse && sk2->sk_reuse &&
6705 			     sk2->sk_state != SCTP_SS_LISTENING))
6706 				continue;
6707 
6708 			if (sctp_bind_addr_conflict(&ep2->base.bind_addr, addr,
6709 						 sctp_sk(sk2), sctp_sk(sk))) {
6710 				ret = (long)sk2;
6711 				goto fail_unlock;
6712 			}
6713 		}
6714 
6715 		pr_debug("%s: found a match\n", __func__);
6716 	}
6717 pp_not_found:
6718 	/* If there was a hash table miss, create a new port.  */
6719 	ret = 1;
6720 	if (!pp && !(pp = sctp_bucket_create(head, sock_net(sk), snum)))
6721 		goto fail_unlock;
6722 
6723 	/* In either case (hit or miss), make sure fastreuse is 1 only
6724 	 * if sk->sk_reuse is too (that is, if the caller requested
6725 	 * SO_REUSEADDR on this socket -sk-).
6726 	 */
6727 	if (hlist_empty(&pp->owner)) {
6728 		if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
6729 			pp->fastreuse = 1;
6730 		else
6731 			pp->fastreuse = 0;
6732 	} else if (pp->fastreuse &&
6733 		(!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
6734 		pp->fastreuse = 0;
6735 
6736 	/* We are set, so fill up all the data in the hash table
6737 	 * entry, tie the socket list information with the rest of the
6738 	 * sockets FIXME: Blurry, NPI (ipg).
6739 	 */
6740 success:
6741 	if (!sctp_sk(sk)->bind_hash) {
6742 		inet_sk(sk)->inet_num = snum;
6743 		sk_add_bind_node(sk, &pp->owner);
6744 		sctp_sk(sk)->bind_hash = pp;
6745 	}
6746 	ret = 0;
6747 
6748 fail_unlock:
6749 	spin_unlock(&head->lock);
6750 
6751 fail:
6752 	local_bh_enable();
6753 	return ret;
6754 }
6755 
6756 /* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
6757  * port is requested.
6758  */
6759 static int sctp_get_port(struct sock *sk, unsigned short snum)
6760 {
6761 	union sctp_addr addr;
6762 	struct sctp_af *af = sctp_sk(sk)->pf->af;
6763 
6764 	/* Set up a dummy address struct from the sk. */
6765 	af->from_sk(&addr, sk);
6766 	addr.v4.sin_port = htons(snum);
6767 
6768 	/* Note: sk->sk_num gets filled in if ephemeral port request. */
6769 	return !!sctp_get_port_local(sk, &addr);
6770 }
6771 
6772 /*
6773  *  Move a socket to LISTENING state.
6774  */
6775 static int sctp_listen_start(struct sock *sk, int backlog)
6776 {
6777 	struct sctp_sock *sp = sctp_sk(sk);
6778 	struct sctp_endpoint *ep = sp->ep;
6779 	struct crypto_shash *tfm = NULL;
6780 	char alg[32];
6781 
6782 	/* Allocate HMAC for generating cookie. */
6783 	if (!sp->hmac && sp->sctp_hmac_alg) {
6784 		sprintf(alg, "hmac(%s)", sp->sctp_hmac_alg);
6785 		tfm = crypto_alloc_shash(alg, 0, 0);
6786 		if (IS_ERR(tfm)) {
6787 			net_info_ratelimited("failed to load transform for %s: %ld\n",
6788 					     sp->sctp_hmac_alg, PTR_ERR(tfm));
6789 			return -ENOSYS;
6790 		}
6791 		sctp_sk(sk)->hmac = tfm;
6792 	}
6793 
6794 	/*
6795 	 * If a bind() or sctp_bindx() is not called prior to a listen()
6796 	 * call that allows new associations to be accepted, the system
6797 	 * picks an ephemeral port and will choose an address set equivalent
6798 	 * to binding with a wildcard address.
6799 	 *
6800 	 * This is not currently spelled out in the SCTP sockets
6801 	 * extensions draft, but follows the practice as seen in TCP
6802 	 * sockets.
6803 	 *
6804 	 */
6805 	sk->sk_state = SCTP_SS_LISTENING;
6806 	if (!ep->base.bind_addr.port) {
6807 		if (sctp_autobind(sk))
6808 			return -EAGAIN;
6809 	} else {
6810 		if (sctp_get_port(sk, inet_sk(sk)->inet_num)) {
6811 			sk->sk_state = SCTP_SS_CLOSED;
6812 			return -EADDRINUSE;
6813 		}
6814 	}
6815 
6816 	sk->sk_max_ack_backlog = backlog;
6817 	sctp_hash_endpoint(ep);
6818 	return 0;
6819 }
6820 
6821 /*
6822  * 4.1.3 / 5.1.3 listen()
6823  *
6824  *   By default, new associations are not accepted for UDP style sockets.
6825  *   An application uses listen() to mark a socket as being able to
6826  *   accept new associations.
6827  *
6828  *   On TCP style sockets, applications use listen() to ready the SCTP
6829  *   endpoint for accepting inbound associations.
6830  *
6831  *   On both types of endpoints a backlog of '0' disables listening.
6832  *
6833  *  Move a socket to LISTENING state.
6834  */
6835 int sctp_inet_listen(struct socket *sock, int backlog)
6836 {
6837 	struct sock *sk = sock->sk;
6838 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
6839 	int err = -EINVAL;
6840 
6841 	if (unlikely(backlog < 0))
6842 		return err;
6843 
6844 	lock_sock(sk);
6845 
6846 	/* Peeled-off sockets are not allowed to listen().  */
6847 	if (sctp_style(sk, UDP_HIGH_BANDWIDTH))
6848 		goto out;
6849 
6850 	if (sock->state != SS_UNCONNECTED)
6851 		goto out;
6852 
6853 	/* If backlog is zero, disable listening. */
6854 	if (!backlog) {
6855 		if (sctp_sstate(sk, CLOSED))
6856 			goto out;
6857 
6858 		err = 0;
6859 		sctp_unhash_endpoint(ep);
6860 		sk->sk_state = SCTP_SS_CLOSED;
6861 		if (sk->sk_reuse)
6862 			sctp_sk(sk)->bind_hash->fastreuse = 1;
6863 		goto out;
6864 	}
6865 
6866 	/* If we are already listening, just update the backlog */
6867 	if (sctp_sstate(sk, LISTENING))
6868 		sk->sk_max_ack_backlog = backlog;
6869 	else {
6870 		err = sctp_listen_start(sk, backlog);
6871 		if (err)
6872 			goto out;
6873 	}
6874 
6875 	err = 0;
6876 out:
6877 	release_sock(sk);
6878 	return err;
6879 }
6880 
6881 /*
6882  * This function is done by modeling the current datagram_poll() and the
6883  * tcp_poll().  Note that, based on these implementations, we don't
6884  * lock the socket in this function, even though it seems that,
6885  * ideally, locking or some other mechanisms can be used to ensure
6886  * the integrity of the counters (sndbuf and wmem_alloc) used
6887  * in this place.  We assume that we don't need locks either until proven
6888  * otherwise.
6889  *
6890  * Another thing to note is that we include the Async I/O support
6891  * here, again, by modeling the current TCP/UDP code.  We don't have
6892  * a good way to test with it yet.
6893  */
6894 unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
6895 {
6896 	struct sock *sk = sock->sk;
6897 	struct sctp_sock *sp = sctp_sk(sk);
6898 	unsigned int mask;
6899 
6900 	poll_wait(file, sk_sleep(sk), wait);
6901 
6902 	sock_rps_record_flow(sk);
6903 
6904 	/* A TCP-style listening socket becomes readable when the accept queue
6905 	 * is not empty.
6906 	 */
6907 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
6908 		return (!list_empty(&sp->ep->asocs)) ?
6909 			(POLLIN | POLLRDNORM) : 0;
6910 
6911 	mask = 0;
6912 
6913 	/* Is there any exceptional events?  */
6914 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
6915 		mask |= POLLERR |
6916 			(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0);
6917 	if (sk->sk_shutdown & RCV_SHUTDOWN)
6918 		mask |= POLLRDHUP | POLLIN | POLLRDNORM;
6919 	if (sk->sk_shutdown == SHUTDOWN_MASK)
6920 		mask |= POLLHUP;
6921 
6922 	/* Is it readable?  Reconsider this code with TCP-style support.  */
6923 	if (!skb_queue_empty(&sk->sk_receive_queue))
6924 		mask |= POLLIN | POLLRDNORM;
6925 
6926 	/* The association is either gone or not ready.  */
6927 	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
6928 		return mask;
6929 
6930 	/* Is it writable?  */
6931 	if (sctp_writeable(sk)) {
6932 		mask |= POLLOUT | POLLWRNORM;
6933 	} else {
6934 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
6935 		/*
6936 		 * Since the socket is not locked, the buffer
6937 		 * might be made available after the writeable check and
6938 		 * before the bit is set.  This could cause a lost I/O
6939 		 * signal.  tcp_poll() has a race breaker for this race
6940 		 * condition.  Based on their implementation, we put
6941 		 * in the following code to cover it as well.
6942 		 */
6943 		if (sctp_writeable(sk))
6944 			mask |= POLLOUT | POLLWRNORM;
6945 	}
6946 	return mask;
6947 }
6948 
6949 /********************************************************************
6950  * 2nd Level Abstractions
6951  ********************************************************************/
6952 
6953 static struct sctp_bind_bucket *sctp_bucket_create(
6954 	struct sctp_bind_hashbucket *head, struct net *net, unsigned short snum)
6955 {
6956 	struct sctp_bind_bucket *pp;
6957 
6958 	pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
6959 	if (pp) {
6960 		SCTP_DBG_OBJCNT_INC(bind_bucket);
6961 		pp->port = snum;
6962 		pp->fastreuse = 0;
6963 		INIT_HLIST_HEAD(&pp->owner);
6964 		pp->net = net;
6965 		hlist_add_head(&pp->node, &head->chain);
6966 	}
6967 	return pp;
6968 }
6969 
6970 /* Caller must hold hashbucket lock for this tb with local BH disabled */
6971 static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
6972 {
6973 	if (pp && hlist_empty(&pp->owner)) {
6974 		__hlist_del(&pp->node);
6975 		kmem_cache_free(sctp_bucket_cachep, pp);
6976 		SCTP_DBG_OBJCNT_DEC(bind_bucket);
6977 	}
6978 }
6979 
6980 /* Release this socket's reference to a local port.  */
6981 static inline void __sctp_put_port(struct sock *sk)
6982 {
6983 	struct sctp_bind_hashbucket *head =
6984 		&sctp_port_hashtable[sctp_phashfn(sock_net(sk),
6985 						  inet_sk(sk)->inet_num)];
6986 	struct sctp_bind_bucket *pp;
6987 
6988 	spin_lock(&head->lock);
6989 	pp = sctp_sk(sk)->bind_hash;
6990 	__sk_del_bind_node(sk);
6991 	sctp_sk(sk)->bind_hash = NULL;
6992 	inet_sk(sk)->inet_num = 0;
6993 	sctp_bucket_destroy(pp);
6994 	spin_unlock(&head->lock);
6995 }
6996 
6997 void sctp_put_port(struct sock *sk)
6998 {
6999 	local_bh_disable();
7000 	__sctp_put_port(sk);
7001 	local_bh_enable();
7002 }
7003 
7004 /*
7005  * The system picks an ephemeral port and choose an address set equivalent
7006  * to binding with a wildcard address.
7007  * One of those addresses will be the primary address for the association.
7008  * This automatically enables the multihoming capability of SCTP.
7009  */
7010 static int sctp_autobind(struct sock *sk)
7011 {
7012 	union sctp_addr autoaddr;
7013 	struct sctp_af *af;
7014 	__be16 port;
7015 
7016 	/* Initialize a local sockaddr structure to INADDR_ANY. */
7017 	af = sctp_sk(sk)->pf->af;
7018 
7019 	port = htons(inet_sk(sk)->inet_num);
7020 	af->inaddr_any(&autoaddr, port);
7021 
7022 	return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
7023 }
7024 
7025 /* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
7026  *
7027  * From RFC 2292
7028  * 4.2 The cmsghdr Structure *
7029  *
7030  * When ancillary data is sent or received, any number of ancillary data
7031  * objects can be specified by the msg_control and msg_controllen members of
7032  * the msghdr structure, because each object is preceded by
7033  * a cmsghdr structure defining the object's length (the cmsg_len member).
7034  * Historically Berkeley-derived implementations have passed only one object
7035  * at a time, but this API allows multiple objects to be
7036  * passed in a single call to sendmsg() or recvmsg(). The following example
7037  * shows two ancillary data objects in a control buffer.
7038  *
7039  *   |<--------------------------- msg_controllen -------------------------->|
7040  *   |                                                                       |
7041  *
7042  *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
7043  *
7044  *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
7045  *   |                                   |                                   |
7046  *
7047  *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
7048  *
7049  *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
7050  *   |                                |  |                                |  |
7051  *
7052  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
7053  *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
7054  *
7055  *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
7056  *
7057  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
7058  *    ^
7059  *    |
7060  *
7061  * msg_control
7062  * points here
7063  */
7064 static int sctp_msghdr_parse(const struct msghdr *msg, sctp_cmsgs_t *cmsgs)
7065 {
7066 	struct cmsghdr *cmsg;
7067 	struct msghdr *my_msg = (struct msghdr *)msg;
7068 
7069 	for_each_cmsghdr(cmsg, my_msg) {
7070 		if (!CMSG_OK(my_msg, cmsg))
7071 			return -EINVAL;
7072 
7073 		/* Should we parse this header or ignore?  */
7074 		if (cmsg->cmsg_level != IPPROTO_SCTP)
7075 			continue;
7076 
7077 		/* Strictly check lengths following example in SCM code.  */
7078 		switch (cmsg->cmsg_type) {
7079 		case SCTP_INIT:
7080 			/* SCTP Socket API Extension
7081 			 * 5.3.1 SCTP Initiation Structure (SCTP_INIT)
7082 			 *
7083 			 * This cmsghdr structure provides information for
7084 			 * initializing new SCTP associations with sendmsg().
7085 			 * The SCTP_INITMSG socket option uses this same data
7086 			 * structure.  This structure is not used for
7087 			 * recvmsg().
7088 			 *
7089 			 * cmsg_level    cmsg_type      cmsg_data[]
7090 			 * ------------  ------------   ----------------------
7091 			 * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
7092 			 */
7093 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_initmsg)))
7094 				return -EINVAL;
7095 
7096 			cmsgs->init = CMSG_DATA(cmsg);
7097 			break;
7098 
7099 		case SCTP_SNDRCV:
7100 			/* SCTP Socket API Extension
7101 			 * 5.3.2 SCTP Header Information Structure(SCTP_SNDRCV)
7102 			 *
7103 			 * This cmsghdr structure specifies SCTP options for
7104 			 * sendmsg() and describes SCTP header information
7105 			 * about a received message through recvmsg().
7106 			 *
7107 			 * cmsg_level    cmsg_type      cmsg_data[]
7108 			 * ------------  ------------   ----------------------
7109 			 * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
7110 			 */
7111 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
7112 				return -EINVAL;
7113 
7114 			cmsgs->srinfo = CMSG_DATA(cmsg);
7115 
7116 			if (cmsgs->srinfo->sinfo_flags &
7117 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
7118 			      SCTP_SACK_IMMEDIATELY | SCTP_PR_SCTP_MASK |
7119 			      SCTP_ABORT | SCTP_EOF))
7120 				return -EINVAL;
7121 			break;
7122 
7123 		case SCTP_SNDINFO:
7124 			/* SCTP Socket API Extension
7125 			 * 5.3.4 SCTP Send Information Structure (SCTP_SNDINFO)
7126 			 *
7127 			 * This cmsghdr structure specifies SCTP options for
7128 			 * sendmsg(). This structure and SCTP_RCVINFO replaces
7129 			 * SCTP_SNDRCV which has been deprecated.
7130 			 *
7131 			 * cmsg_level    cmsg_type      cmsg_data[]
7132 			 * ------------  ------------   ---------------------
7133 			 * IPPROTO_SCTP  SCTP_SNDINFO    struct sctp_sndinfo
7134 			 */
7135 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct sctp_sndinfo)))
7136 				return -EINVAL;
7137 
7138 			cmsgs->sinfo = CMSG_DATA(cmsg);
7139 
7140 			if (cmsgs->sinfo->snd_flags &
7141 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
7142 			      SCTP_SACK_IMMEDIATELY | SCTP_PR_SCTP_MASK |
7143 			      SCTP_ABORT | SCTP_EOF))
7144 				return -EINVAL;
7145 			break;
7146 		default:
7147 			return -EINVAL;
7148 		}
7149 	}
7150 
7151 	return 0;
7152 }
7153 
7154 /*
7155  * Wait for a packet..
7156  * Note: This function is the same function as in core/datagram.c
7157  * with a few modifications to make lksctp work.
7158  */
7159 static int sctp_wait_for_packet(struct sock *sk, int *err, long *timeo_p)
7160 {
7161 	int error;
7162 	DEFINE_WAIT(wait);
7163 
7164 	prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
7165 
7166 	/* Socket errors? */
7167 	error = sock_error(sk);
7168 	if (error)
7169 		goto out;
7170 
7171 	if (!skb_queue_empty(&sk->sk_receive_queue))
7172 		goto ready;
7173 
7174 	/* Socket shut down?  */
7175 	if (sk->sk_shutdown & RCV_SHUTDOWN)
7176 		goto out;
7177 
7178 	/* Sequenced packets can come disconnected.  If so we report the
7179 	 * problem.
7180 	 */
7181 	error = -ENOTCONN;
7182 
7183 	/* Is there a good reason to think that we may receive some data?  */
7184 	if (list_empty(&sctp_sk(sk)->ep->asocs) && !sctp_sstate(sk, LISTENING))
7185 		goto out;
7186 
7187 	/* Handle signals.  */
7188 	if (signal_pending(current))
7189 		goto interrupted;
7190 
7191 	/* Let another process have a go.  Since we are going to sleep
7192 	 * anyway.  Note: This may cause odd behaviors if the message
7193 	 * does not fit in the user's buffer, but this seems to be the
7194 	 * only way to honor MSG_DONTWAIT realistically.
7195 	 */
7196 	release_sock(sk);
7197 	*timeo_p = schedule_timeout(*timeo_p);
7198 	lock_sock(sk);
7199 
7200 ready:
7201 	finish_wait(sk_sleep(sk), &wait);
7202 	return 0;
7203 
7204 interrupted:
7205 	error = sock_intr_errno(*timeo_p);
7206 
7207 out:
7208 	finish_wait(sk_sleep(sk), &wait);
7209 	*err = error;
7210 	return error;
7211 }
7212 
7213 /* Receive a datagram.
7214  * Note: This is pretty much the same routine as in core/datagram.c
7215  * with a few changes to make lksctp work.
7216  */
7217 struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
7218 				       int noblock, int *err)
7219 {
7220 	int error;
7221 	struct sk_buff *skb;
7222 	long timeo;
7223 
7224 	timeo = sock_rcvtimeo(sk, noblock);
7225 
7226 	pr_debug("%s: timeo:%ld, max:%ld\n", __func__, timeo,
7227 		 MAX_SCHEDULE_TIMEOUT);
7228 
7229 	do {
7230 		/* Again only user level code calls this function,
7231 		 * so nothing interrupt level
7232 		 * will suddenly eat the receive_queue.
7233 		 *
7234 		 *  Look at current nfs client by the way...
7235 		 *  However, this function was correct in any case. 8)
7236 		 */
7237 		if (flags & MSG_PEEK) {
7238 			skb = skb_peek(&sk->sk_receive_queue);
7239 			if (skb)
7240 				atomic_inc(&skb->users);
7241 		} else {
7242 			skb = __skb_dequeue(&sk->sk_receive_queue);
7243 		}
7244 
7245 		if (skb)
7246 			return skb;
7247 
7248 		/* Caller is allowed not to check sk->sk_err before calling. */
7249 		error = sock_error(sk);
7250 		if (error)
7251 			goto no_packet;
7252 
7253 		if (sk->sk_shutdown & RCV_SHUTDOWN)
7254 			break;
7255 
7256 		if (sk_can_busy_loop(sk) &&
7257 		    sk_busy_loop(sk, noblock))
7258 			continue;
7259 
7260 		/* User doesn't want to wait.  */
7261 		error = -EAGAIN;
7262 		if (!timeo)
7263 			goto no_packet;
7264 	} while (sctp_wait_for_packet(sk, err, &timeo) == 0);
7265 
7266 	return NULL;
7267 
7268 no_packet:
7269 	*err = error;
7270 	return NULL;
7271 }
7272 
7273 /* If sndbuf has changed, wake up per association sndbuf waiters.  */
7274 static void __sctp_write_space(struct sctp_association *asoc)
7275 {
7276 	struct sock *sk = asoc->base.sk;
7277 
7278 	if (sctp_wspace(asoc) <= 0)
7279 		return;
7280 
7281 	if (waitqueue_active(&asoc->wait))
7282 		wake_up_interruptible(&asoc->wait);
7283 
7284 	if (sctp_writeable(sk)) {
7285 		struct socket_wq *wq;
7286 
7287 		rcu_read_lock();
7288 		wq = rcu_dereference(sk->sk_wq);
7289 		if (wq) {
7290 			if (waitqueue_active(&wq->wait))
7291 				wake_up_interruptible(&wq->wait);
7292 
7293 			/* Note that we try to include the Async I/O support
7294 			 * here by modeling from the current TCP/UDP code.
7295 			 * We have not tested with it yet.
7296 			 */
7297 			if (!(sk->sk_shutdown & SEND_SHUTDOWN))
7298 				sock_wake_async(wq, SOCK_WAKE_SPACE, POLL_OUT);
7299 		}
7300 		rcu_read_unlock();
7301 	}
7302 }
7303 
7304 static void sctp_wake_up_waiters(struct sock *sk,
7305 				 struct sctp_association *asoc)
7306 {
7307 	struct sctp_association *tmp = asoc;
7308 
7309 	/* We do accounting for the sndbuf space per association,
7310 	 * so we only need to wake our own association.
7311 	 */
7312 	if (asoc->ep->sndbuf_policy)
7313 		return __sctp_write_space(asoc);
7314 
7315 	/* If association goes down and is just flushing its
7316 	 * outq, then just normally notify others.
7317 	 */
7318 	if (asoc->base.dead)
7319 		return sctp_write_space(sk);
7320 
7321 	/* Accounting for the sndbuf space is per socket, so we
7322 	 * need to wake up others, try to be fair and in case of
7323 	 * other associations, let them have a go first instead
7324 	 * of just doing a sctp_write_space() call.
7325 	 *
7326 	 * Note that we reach sctp_wake_up_waiters() only when
7327 	 * associations free up queued chunks, thus we are under
7328 	 * lock and the list of associations on a socket is
7329 	 * guaranteed not to change.
7330 	 */
7331 	for (tmp = list_next_entry(tmp, asocs); 1;
7332 	     tmp = list_next_entry(tmp, asocs)) {
7333 		/* Manually skip the head element. */
7334 		if (&tmp->asocs == &((sctp_sk(sk))->ep->asocs))
7335 			continue;
7336 		/* Wake up association. */
7337 		__sctp_write_space(tmp);
7338 		/* We've reached the end. */
7339 		if (tmp == asoc)
7340 			break;
7341 	}
7342 }
7343 
7344 /* Do accounting for the sndbuf space.
7345  * Decrement the used sndbuf space of the corresponding association by the
7346  * data size which was just transmitted(freed).
7347  */
7348 static void sctp_wfree(struct sk_buff *skb)
7349 {
7350 	struct sctp_chunk *chunk = skb_shinfo(skb)->destructor_arg;
7351 	struct sctp_association *asoc = chunk->asoc;
7352 	struct sock *sk = asoc->base.sk;
7353 
7354 	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
7355 				sizeof(struct sk_buff) +
7356 				sizeof(struct sctp_chunk);
7357 
7358 	atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
7359 
7360 	/*
7361 	 * This undoes what is done via sctp_set_owner_w and sk_mem_charge
7362 	 */
7363 	sk->sk_wmem_queued   -= skb->truesize;
7364 	sk_mem_uncharge(sk, skb->truesize);
7365 
7366 	sock_wfree(skb);
7367 	sctp_wake_up_waiters(sk, asoc);
7368 
7369 	sctp_association_put(asoc);
7370 }
7371 
7372 /* Do accounting for the receive space on the socket.
7373  * Accounting for the association is done in ulpevent.c
7374  * We set this as a destructor for the cloned data skbs so that
7375  * accounting is done at the correct time.
7376  */
7377 void sctp_sock_rfree(struct sk_buff *skb)
7378 {
7379 	struct sock *sk = skb->sk;
7380 	struct sctp_ulpevent *event = sctp_skb2event(skb);
7381 
7382 	atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
7383 
7384 	/*
7385 	 * Mimic the behavior of sock_rfree
7386 	 */
7387 	sk_mem_uncharge(sk, event->rmem_len);
7388 }
7389 
7390 
7391 /* Helper function to wait for space in the sndbuf.  */
7392 static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
7393 				size_t msg_len)
7394 {
7395 	struct sock *sk = asoc->base.sk;
7396 	int err = 0;
7397 	long current_timeo = *timeo_p;
7398 	DEFINE_WAIT(wait);
7399 
7400 	pr_debug("%s: asoc:%p, timeo:%ld, msg_len:%zu\n", __func__, asoc,
7401 		 *timeo_p, msg_len);
7402 
7403 	/* Increment the association's refcnt.  */
7404 	sctp_association_hold(asoc);
7405 
7406 	/* Wait on the association specific sndbuf space. */
7407 	for (;;) {
7408 		prepare_to_wait_exclusive(&asoc->wait, &wait,
7409 					  TASK_INTERRUPTIBLE);
7410 		if (!*timeo_p)
7411 			goto do_nonblock;
7412 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
7413 		    asoc->base.dead)
7414 			goto do_error;
7415 		if (signal_pending(current))
7416 			goto do_interrupted;
7417 		if (msg_len <= sctp_wspace(asoc))
7418 			break;
7419 
7420 		/* Let another process have a go.  Since we are going
7421 		 * to sleep anyway.
7422 		 */
7423 		release_sock(sk);
7424 		current_timeo = schedule_timeout(current_timeo);
7425 		BUG_ON(sk != asoc->base.sk);
7426 		lock_sock(sk);
7427 
7428 		*timeo_p = current_timeo;
7429 	}
7430 
7431 out:
7432 	finish_wait(&asoc->wait, &wait);
7433 
7434 	/* Release the association's refcnt.  */
7435 	sctp_association_put(asoc);
7436 
7437 	return err;
7438 
7439 do_error:
7440 	err = -EPIPE;
7441 	goto out;
7442 
7443 do_interrupted:
7444 	err = sock_intr_errno(*timeo_p);
7445 	goto out;
7446 
7447 do_nonblock:
7448 	err = -EAGAIN;
7449 	goto out;
7450 }
7451 
7452 void sctp_data_ready(struct sock *sk)
7453 {
7454 	struct socket_wq *wq;
7455 
7456 	rcu_read_lock();
7457 	wq = rcu_dereference(sk->sk_wq);
7458 	if (skwq_has_sleeper(wq))
7459 		wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
7460 						POLLRDNORM | POLLRDBAND);
7461 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
7462 	rcu_read_unlock();
7463 }
7464 
7465 /* If socket sndbuf has changed, wake up all per association waiters.  */
7466 void sctp_write_space(struct sock *sk)
7467 {
7468 	struct sctp_association *asoc;
7469 
7470 	/* Wake up the tasks in each wait queue.  */
7471 	list_for_each_entry(asoc, &((sctp_sk(sk))->ep->asocs), asocs) {
7472 		__sctp_write_space(asoc);
7473 	}
7474 }
7475 
7476 /* Is there any sndbuf space available on the socket?
7477  *
7478  * Note that sk_wmem_alloc is the sum of the send buffers on all of the
7479  * associations on the same socket.  For a UDP-style socket with
7480  * multiple associations, it is possible for it to be "unwriteable"
7481  * prematurely.  I assume that this is acceptable because
7482  * a premature "unwriteable" is better than an accidental "writeable" which
7483  * would cause an unwanted block under certain circumstances.  For the 1-1
7484  * UDP-style sockets or TCP-style sockets, this code should work.
7485  *  - Daisy
7486  */
7487 static int sctp_writeable(struct sock *sk)
7488 {
7489 	int amt = 0;
7490 
7491 	amt = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
7492 	if (amt < 0)
7493 		amt = 0;
7494 	return amt;
7495 }
7496 
7497 /* Wait for an association to go into ESTABLISHED state. If timeout is 0,
7498  * returns immediately with EINPROGRESS.
7499  */
7500 static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
7501 {
7502 	struct sock *sk = asoc->base.sk;
7503 	int err = 0;
7504 	long current_timeo = *timeo_p;
7505 	DEFINE_WAIT(wait);
7506 
7507 	pr_debug("%s: asoc:%p, timeo:%ld\n", __func__, asoc, *timeo_p);
7508 
7509 	/* Increment the association's refcnt.  */
7510 	sctp_association_hold(asoc);
7511 
7512 	for (;;) {
7513 		prepare_to_wait_exclusive(&asoc->wait, &wait,
7514 					  TASK_INTERRUPTIBLE);
7515 		if (!*timeo_p)
7516 			goto do_nonblock;
7517 		if (sk->sk_shutdown & RCV_SHUTDOWN)
7518 			break;
7519 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
7520 		    asoc->base.dead)
7521 			goto do_error;
7522 		if (signal_pending(current))
7523 			goto do_interrupted;
7524 
7525 		if (sctp_state(asoc, ESTABLISHED))
7526 			break;
7527 
7528 		/* Let another process have a go.  Since we are going
7529 		 * to sleep anyway.
7530 		 */
7531 		release_sock(sk);
7532 		current_timeo = schedule_timeout(current_timeo);
7533 		lock_sock(sk);
7534 
7535 		*timeo_p = current_timeo;
7536 	}
7537 
7538 out:
7539 	finish_wait(&asoc->wait, &wait);
7540 
7541 	/* Release the association's refcnt.  */
7542 	sctp_association_put(asoc);
7543 
7544 	return err;
7545 
7546 do_error:
7547 	if (asoc->init_err_counter + 1 > asoc->max_init_attempts)
7548 		err = -ETIMEDOUT;
7549 	else
7550 		err = -ECONNREFUSED;
7551 	goto out;
7552 
7553 do_interrupted:
7554 	err = sock_intr_errno(*timeo_p);
7555 	goto out;
7556 
7557 do_nonblock:
7558 	err = -EINPROGRESS;
7559 	goto out;
7560 }
7561 
7562 static int sctp_wait_for_accept(struct sock *sk, long timeo)
7563 {
7564 	struct sctp_endpoint *ep;
7565 	int err = 0;
7566 	DEFINE_WAIT(wait);
7567 
7568 	ep = sctp_sk(sk)->ep;
7569 
7570 
7571 	for (;;) {
7572 		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
7573 					  TASK_INTERRUPTIBLE);
7574 
7575 		if (list_empty(&ep->asocs)) {
7576 			release_sock(sk);
7577 			timeo = schedule_timeout(timeo);
7578 			lock_sock(sk);
7579 		}
7580 
7581 		err = -EINVAL;
7582 		if (!sctp_sstate(sk, LISTENING))
7583 			break;
7584 
7585 		err = 0;
7586 		if (!list_empty(&ep->asocs))
7587 			break;
7588 
7589 		err = sock_intr_errno(timeo);
7590 		if (signal_pending(current))
7591 			break;
7592 
7593 		err = -EAGAIN;
7594 		if (!timeo)
7595 			break;
7596 	}
7597 
7598 	finish_wait(sk_sleep(sk), &wait);
7599 
7600 	return err;
7601 }
7602 
7603 static void sctp_wait_for_close(struct sock *sk, long timeout)
7604 {
7605 	DEFINE_WAIT(wait);
7606 
7607 	do {
7608 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
7609 		if (list_empty(&sctp_sk(sk)->ep->asocs))
7610 			break;
7611 		release_sock(sk);
7612 		timeout = schedule_timeout(timeout);
7613 		lock_sock(sk);
7614 	} while (!signal_pending(current) && timeout);
7615 
7616 	finish_wait(sk_sleep(sk), &wait);
7617 }
7618 
7619 static void sctp_skb_set_owner_r_frag(struct sk_buff *skb, struct sock *sk)
7620 {
7621 	struct sk_buff *frag;
7622 
7623 	if (!skb->data_len)
7624 		goto done;
7625 
7626 	/* Don't forget the fragments. */
7627 	skb_walk_frags(skb, frag)
7628 		sctp_skb_set_owner_r_frag(frag, sk);
7629 
7630 done:
7631 	sctp_skb_set_owner_r(skb, sk);
7632 }
7633 
7634 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
7635 		    struct sctp_association *asoc)
7636 {
7637 	struct inet_sock *inet = inet_sk(sk);
7638 	struct inet_sock *newinet;
7639 
7640 	newsk->sk_type = sk->sk_type;
7641 	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
7642 	newsk->sk_flags = sk->sk_flags;
7643 	newsk->sk_tsflags = sk->sk_tsflags;
7644 	newsk->sk_no_check_tx = sk->sk_no_check_tx;
7645 	newsk->sk_no_check_rx = sk->sk_no_check_rx;
7646 	newsk->sk_reuse = sk->sk_reuse;
7647 
7648 	newsk->sk_shutdown = sk->sk_shutdown;
7649 	newsk->sk_destruct = sctp_destruct_sock;
7650 	newsk->sk_family = sk->sk_family;
7651 	newsk->sk_protocol = IPPROTO_SCTP;
7652 	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
7653 	newsk->sk_sndbuf = sk->sk_sndbuf;
7654 	newsk->sk_rcvbuf = sk->sk_rcvbuf;
7655 	newsk->sk_lingertime = sk->sk_lingertime;
7656 	newsk->sk_rcvtimeo = sk->sk_rcvtimeo;
7657 	newsk->sk_sndtimeo = sk->sk_sndtimeo;
7658 	newsk->sk_rxhash = sk->sk_rxhash;
7659 
7660 	newinet = inet_sk(newsk);
7661 
7662 	/* Initialize sk's sport, dport, rcv_saddr and daddr for
7663 	 * getsockname() and getpeername()
7664 	 */
7665 	newinet->inet_sport = inet->inet_sport;
7666 	newinet->inet_saddr = inet->inet_saddr;
7667 	newinet->inet_rcv_saddr = inet->inet_rcv_saddr;
7668 	newinet->inet_dport = htons(asoc->peer.port);
7669 	newinet->pmtudisc = inet->pmtudisc;
7670 	newinet->inet_id = asoc->next_tsn ^ jiffies;
7671 
7672 	newinet->uc_ttl = inet->uc_ttl;
7673 	newinet->mc_loop = 1;
7674 	newinet->mc_ttl = 1;
7675 	newinet->mc_index = 0;
7676 	newinet->mc_list = NULL;
7677 
7678 	if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
7679 		net_enable_timestamp();
7680 
7681 	security_sk_clone(sk, newsk);
7682 }
7683 
7684 static inline void sctp_copy_descendant(struct sock *sk_to,
7685 					const struct sock *sk_from)
7686 {
7687 	int ancestor_size = sizeof(struct inet_sock) +
7688 			    sizeof(struct sctp_sock) -
7689 			    offsetof(struct sctp_sock, auto_asconf_list);
7690 
7691 	if (sk_from->sk_family == PF_INET6)
7692 		ancestor_size += sizeof(struct ipv6_pinfo);
7693 
7694 	__inet_sk_copy_descendant(sk_to, sk_from, ancestor_size);
7695 }
7696 
7697 /* Populate the fields of the newsk from the oldsk and migrate the assoc
7698  * and its messages to the newsk.
7699  */
7700 static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
7701 			      struct sctp_association *assoc,
7702 			      sctp_socket_type_t type)
7703 {
7704 	struct sctp_sock *oldsp = sctp_sk(oldsk);
7705 	struct sctp_sock *newsp = sctp_sk(newsk);
7706 	struct sctp_bind_bucket *pp; /* hash list port iterator */
7707 	struct sctp_endpoint *newep = newsp->ep;
7708 	struct sk_buff *skb, *tmp;
7709 	struct sctp_ulpevent *event;
7710 	struct sctp_bind_hashbucket *head;
7711 
7712 	/* Migrate socket buffer sizes and all the socket level options to the
7713 	 * new socket.
7714 	 */
7715 	newsk->sk_sndbuf = oldsk->sk_sndbuf;
7716 	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
7717 	/* Brute force copy old sctp opt. */
7718 	sctp_copy_descendant(newsk, oldsk);
7719 
7720 	/* Restore the ep value that was overwritten with the above structure
7721 	 * copy.
7722 	 */
7723 	newsp->ep = newep;
7724 	newsp->hmac = NULL;
7725 
7726 	/* Hook this new socket in to the bind_hash list. */
7727 	head = &sctp_port_hashtable[sctp_phashfn(sock_net(oldsk),
7728 						 inet_sk(oldsk)->inet_num)];
7729 	spin_lock_bh(&head->lock);
7730 	pp = sctp_sk(oldsk)->bind_hash;
7731 	sk_add_bind_node(newsk, &pp->owner);
7732 	sctp_sk(newsk)->bind_hash = pp;
7733 	inet_sk(newsk)->inet_num = inet_sk(oldsk)->inet_num;
7734 	spin_unlock_bh(&head->lock);
7735 
7736 	/* Copy the bind_addr list from the original endpoint to the new
7737 	 * endpoint so that we can handle restarts properly
7738 	 */
7739 	sctp_bind_addr_dup(&newsp->ep->base.bind_addr,
7740 				&oldsp->ep->base.bind_addr, GFP_KERNEL);
7741 
7742 	/* Move any messages in the old socket's receive queue that are for the
7743 	 * peeled off association to the new socket's receive queue.
7744 	 */
7745 	sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
7746 		event = sctp_skb2event(skb);
7747 		if (event->asoc == assoc) {
7748 			__skb_unlink(skb, &oldsk->sk_receive_queue);
7749 			__skb_queue_tail(&newsk->sk_receive_queue, skb);
7750 			sctp_skb_set_owner_r_frag(skb, newsk);
7751 		}
7752 	}
7753 
7754 	/* Clean up any messages pending delivery due to partial
7755 	 * delivery.   Three cases:
7756 	 * 1) No partial deliver;  no work.
7757 	 * 2) Peeling off partial delivery; keep pd_lobby in new pd_lobby.
7758 	 * 3) Peeling off non-partial delivery; move pd_lobby to receive_queue.
7759 	 */
7760 	skb_queue_head_init(&newsp->pd_lobby);
7761 	atomic_set(&sctp_sk(newsk)->pd_mode, assoc->ulpq.pd_mode);
7762 
7763 	if (atomic_read(&sctp_sk(oldsk)->pd_mode)) {
7764 		struct sk_buff_head *queue;
7765 
7766 		/* Decide which queue to move pd_lobby skbs to. */
7767 		if (assoc->ulpq.pd_mode) {
7768 			queue = &newsp->pd_lobby;
7769 		} else
7770 			queue = &newsk->sk_receive_queue;
7771 
7772 		/* Walk through the pd_lobby, looking for skbs that
7773 		 * need moved to the new socket.
7774 		 */
7775 		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
7776 			event = sctp_skb2event(skb);
7777 			if (event->asoc == assoc) {
7778 				__skb_unlink(skb, &oldsp->pd_lobby);
7779 				__skb_queue_tail(queue, skb);
7780 				sctp_skb_set_owner_r_frag(skb, newsk);
7781 			}
7782 		}
7783 
7784 		/* Clear up any skbs waiting for the partial
7785 		 * delivery to finish.
7786 		 */
7787 		if (assoc->ulpq.pd_mode)
7788 			sctp_clear_pd(oldsk, NULL);
7789 
7790 	}
7791 
7792 	sctp_skb_for_each(skb, &assoc->ulpq.reasm, tmp)
7793 		sctp_skb_set_owner_r_frag(skb, newsk);
7794 
7795 	sctp_skb_for_each(skb, &assoc->ulpq.lobby, tmp)
7796 		sctp_skb_set_owner_r_frag(skb, newsk);
7797 
7798 	/* Set the type of socket to indicate that it is peeled off from the
7799 	 * original UDP-style socket or created with the accept() call on a
7800 	 * TCP-style socket..
7801 	 */
7802 	newsp->type = type;
7803 
7804 	/* Mark the new socket "in-use" by the user so that any packets
7805 	 * that may arrive on the association after we've moved it are
7806 	 * queued to the backlog.  This prevents a potential race between
7807 	 * backlog processing on the old socket and new-packet processing
7808 	 * on the new socket.
7809 	 *
7810 	 * The caller has just allocated newsk so we can guarantee that other
7811 	 * paths won't try to lock it and then oldsk.
7812 	 */
7813 	lock_sock_nested(newsk, SINGLE_DEPTH_NESTING);
7814 	sctp_assoc_migrate(assoc, newsk);
7815 
7816 	/* If the association on the newsk is already closed before accept()
7817 	 * is called, set RCV_SHUTDOWN flag.
7818 	 */
7819 	if (sctp_state(assoc, CLOSED) && sctp_style(newsk, TCP)) {
7820 		newsk->sk_state = SCTP_SS_CLOSED;
7821 		newsk->sk_shutdown |= RCV_SHUTDOWN;
7822 	} else {
7823 		newsk->sk_state = SCTP_SS_ESTABLISHED;
7824 	}
7825 
7826 	release_sock(newsk);
7827 }
7828 
7829 
7830 /* This proto struct describes the ULP interface for SCTP.  */
7831 struct proto sctp_prot = {
7832 	.name        =	"SCTP",
7833 	.owner       =	THIS_MODULE,
7834 	.close       =	sctp_close,
7835 	.connect     =	sctp_connect,
7836 	.disconnect  =	sctp_disconnect,
7837 	.accept      =	sctp_accept,
7838 	.ioctl       =	sctp_ioctl,
7839 	.init        =	sctp_init_sock,
7840 	.destroy     =	sctp_destroy_sock,
7841 	.shutdown    =	sctp_shutdown,
7842 	.setsockopt  =	sctp_setsockopt,
7843 	.getsockopt  =	sctp_getsockopt,
7844 	.sendmsg     =	sctp_sendmsg,
7845 	.recvmsg     =	sctp_recvmsg,
7846 	.bind        =	sctp_bind,
7847 	.backlog_rcv =	sctp_backlog_rcv,
7848 	.hash        =	sctp_hash,
7849 	.unhash      =	sctp_unhash,
7850 	.get_port    =	sctp_get_port,
7851 	.obj_size    =  sizeof(struct sctp_sock),
7852 	.sysctl_mem  =  sysctl_sctp_mem,
7853 	.sysctl_rmem =  sysctl_sctp_rmem,
7854 	.sysctl_wmem =  sysctl_sctp_wmem,
7855 	.memory_pressure = &sctp_memory_pressure,
7856 	.enter_memory_pressure = sctp_enter_memory_pressure,
7857 	.memory_allocated = &sctp_memory_allocated,
7858 	.sockets_allocated = &sctp_sockets_allocated,
7859 };
7860 
7861 #if IS_ENABLED(CONFIG_IPV6)
7862 
7863 #include <net/transp_v6.h>
7864 static void sctp_v6_destroy_sock(struct sock *sk)
7865 {
7866 	sctp_destroy_sock(sk);
7867 	inet6_destroy_sock(sk);
7868 }
7869 
7870 struct proto sctpv6_prot = {
7871 	.name		= "SCTPv6",
7872 	.owner		= THIS_MODULE,
7873 	.close		= sctp_close,
7874 	.connect	= sctp_connect,
7875 	.disconnect	= sctp_disconnect,
7876 	.accept		= sctp_accept,
7877 	.ioctl		= sctp_ioctl,
7878 	.init		= sctp_init_sock,
7879 	.destroy	= sctp_v6_destroy_sock,
7880 	.shutdown	= sctp_shutdown,
7881 	.setsockopt	= sctp_setsockopt,
7882 	.getsockopt	= sctp_getsockopt,
7883 	.sendmsg	= sctp_sendmsg,
7884 	.recvmsg	= sctp_recvmsg,
7885 	.bind		= sctp_bind,
7886 	.backlog_rcv	= sctp_backlog_rcv,
7887 	.hash		= sctp_hash,
7888 	.unhash		= sctp_unhash,
7889 	.get_port	= sctp_get_port,
7890 	.obj_size	= sizeof(struct sctp6_sock),
7891 	.sysctl_mem	= sysctl_sctp_mem,
7892 	.sysctl_rmem	= sysctl_sctp_rmem,
7893 	.sysctl_wmem	= sysctl_sctp_wmem,
7894 	.memory_pressure = &sctp_memory_pressure,
7895 	.enter_memory_pressure = sctp_enter_memory_pressure,
7896 	.memory_allocated = &sctp_memory_allocated,
7897 	.sockets_allocated = &sctp_sockets_allocated,
7898 };
7899 #endif /* IS_ENABLED(CONFIG_IPV6) */
7900