xref: /openbmc/linux/net/sctp/socket.c (revision 643d1f7f)
1 /* SCTP kernel reference 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 reference 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  * The SCTP reference 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  * The SCTP reference 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, write to
32  * the Free Software Foundation, 59 Temple Place - Suite 330,
33  * Boston, MA 02111-1307, USA.
34  *
35  * Please send any bug reports or fixes you make to the
36  * email address(es):
37  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
38  *
39  * Or submit a bug report through the following website:
40  *    http://www.sf.net/projects/lksctp
41  *
42  * Written or modified by:
43  *    La Monte H.P. Yarroll <piggy@acm.org>
44  *    Narasimha Budihal     <narsi@refcode.org>
45  *    Karl Knutson          <karl@athena.chicago.il.us>
46  *    Jon Grimm             <jgrimm@us.ibm.com>
47  *    Xingang Guo           <xingang.guo@intel.com>
48  *    Daisy Chang           <daisyc@us.ibm.com>
49  *    Sridhar Samudrala     <samudrala@us.ibm.com>
50  *    Inaky Perez-Gonzalez  <inaky.gonzalez@intel.com>
51  *    Ardelle Fan	    <ardelle.fan@intel.com>
52  *    Ryan Layer	    <rmlayer@us.ibm.com>
53  *    Anup Pemmaiah         <pemmaiah@cc.usu.edu>
54  *    Kevin Gao             <kevin.gao@intel.com>
55  *
56  * Any bugs reported given to us we will try to fix... any fixes shared will
57  * be incorporated into the next SCTP release.
58  */
59 
60 #include <linux/types.h>
61 #include <linux/kernel.h>
62 #include <linux/wait.h>
63 #include <linux/time.h>
64 #include <linux/ip.h>
65 #include <linux/capability.h>
66 #include <linux/fcntl.h>
67 #include <linux/poll.h>
68 #include <linux/init.h>
69 #include <linux/crypto.h>
70 
71 #include <net/ip.h>
72 #include <net/icmp.h>
73 #include <net/route.h>
74 #include <net/ipv6.h>
75 #include <net/inet_common.h>
76 
77 #include <linux/socket.h> /* for sa_family_t */
78 #include <net/sock.h>
79 #include <net/sctp/sctp.h>
80 #include <net/sctp/sm.h>
81 
82 /* WARNING:  Please do not remove the SCTP_STATIC attribute to
83  * any of the functions below as they are used to export functions
84  * used by a project regression testsuite.
85  */
86 
87 /* Forward declarations for internal helper functions. */
88 static int sctp_writeable(struct sock *sk);
89 static void sctp_wfree(struct sk_buff *skb);
90 static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p,
91 				size_t msg_len);
92 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p);
93 static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);
94 static int sctp_wait_for_accept(struct sock *sk, long timeo);
95 static void sctp_wait_for_close(struct sock *sk, long timeo);
96 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
97 					union sctp_addr *addr, int len);
98 static int sctp_bindx_add(struct sock *, struct sockaddr *, int);
99 static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);
100 static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);
101 static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);
102 static int sctp_send_asconf(struct sctp_association *asoc,
103 			    struct sctp_chunk *chunk);
104 static int sctp_do_bind(struct sock *, union sctp_addr *, int);
105 static int sctp_autobind(struct sock *sk);
106 static void sctp_sock_migrate(struct sock *, struct sock *,
107 			      struct sctp_association *, sctp_socket_type_t);
108 static char *sctp_hmac_alg = SCTP_COOKIE_HMAC_ALG;
109 
110 extern struct kmem_cache *sctp_bucket_cachep;
111 extern int sysctl_sctp_mem[3];
112 extern int sysctl_sctp_rmem[3];
113 extern int sysctl_sctp_wmem[3];
114 
115 static int sctp_memory_pressure;
116 static atomic_t sctp_memory_allocated;
117 static atomic_t sctp_sockets_allocated;
118 
119 static void sctp_enter_memory_pressure(void)
120 {
121 	sctp_memory_pressure = 1;
122 }
123 
124 
125 /* Get the sndbuf space available at the time on the association.  */
126 static inline int sctp_wspace(struct sctp_association *asoc)
127 {
128 	int amt;
129 
130 	if (asoc->ep->sndbuf_policy)
131 		amt = asoc->sndbuf_used;
132 	else
133 		amt = atomic_read(&asoc->base.sk->sk_wmem_alloc);
134 
135 	if (amt >= asoc->base.sk->sk_sndbuf) {
136 		if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK)
137 			amt = 0;
138 		else {
139 			amt = sk_stream_wspace(asoc->base.sk);
140 			if (amt < 0)
141 				amt = 0;
142 		}
143 	} else {
144 		amt = asoc->base.sk->sk_sndbuf - amt;
145 	}
146 	return amt;
147 }
148 
149 /* Increment the used sndbuf space count of the corresponding association by
150  * the size of the outgoing data chunk.
151  * Also, set the skb destructor for sndbuf accounting later.
152  *
153  * Since it is always 1-1 between chunk and skb, and also a new skb is always
154  * allocated for chunk bundling in sctp_packet_transmit(), we can use the
155  * destructor in the data chunk skb for the purpose of the sndbuf space
156  * tracking.
157  */
158 static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
159 {
160 	struct sctp_association *asoc = chunk->asoc;
161 	struct sock *sk = asoc->base.sk;
162 
163 	/* The sndbuf space is tracked per association.  */
164 	sctp_association_hold(asoc);
165 
166 	skb_set_owner_w(chunk->skb, sk);
167 
168 	chunk->skb->destructor = sctp_wfree;
169 	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
170 	*((struct sctp_chunk **)(chunk->skb->cb)) = chunk;
171 
172 	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
173 				sizeof(struct sk_buff) +
174 				sizeof(struct sctp_chunk);
175 
176 	atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
177 	sk->sk_wmem_queued += chunk->skb->truesize;
178 	sk_mem_charge(sk, chunk->skb->truesize);
179 }
180 
181 /* Verify that this is a valid address. */
182 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
183 				   int len)
184 {
185 	struct sctp_af *af;
186 
187 	/* Verify basic sockaddr. */
188 	af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
189 	if (!af)
190 		return -EINVAL;
191 
192 	/* Is this a valid SCTP address?  */
193 	if (!af->addr_valid(addr, sctp_sk(sk), NULL))
194 		return -EINVAL;
195 
196 	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
197 		return -EINVAL;
198 
199 	return 0;
200 }
201 
202 /* Look up the association by its id.  If this is not a UDP-style
203  * socket, the ID field is always ignored.
204  */
205 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
206 {
207 	struct sctp_association *asoc = NULL;
208 
209 	/* If this is not a UDP-style socket, assoc id should be ignored. */
210 	if (!sctp_style(sk, UDP)) {
211 		/* Return NULL if the socket state is not ESTABLISHED. It
212 		 * could be a TCP-style listening socket or a socket which
213 		 * hasn't yet called connect() to establish an association.
214 		 */
215 		if (!sctp_sstate(sk, ESTABLISHED))
216 			return NULL;
217 
218 		/* Get the first and the only association from the list. */
219 		if (!list_empty(&sctp_sk(sk)->ep->asocs))
220 			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
221 					  struct sctp_association, asocs);
222 		return asoc;
223 	}
224 
225 	/* Otherwise this is a UDP-style socket. */
226 	if (!id || (id == (sctp_assoc_t)-1))
227 		return NULL;
228 
229 	spin_lock_bh(&sctp_assocs_id_lock);
230 	asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
231 	spin_unlock_bh(&sctp_assocs_id_lock);
232 
233 	if (!asoc || (asoc->base.sk != sk) || asoc->base.dead)
234 		return NULL;
235 
236 	return asoc;
237 }
238 
239 /* Look up the transport from an address and an assoc id. If both address and
240  * id are specified, the associations matching the address and the id should be
241  * the same.
242  */
243 static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
244 					      struct sockaddr_storage *addr,
245 					      sctp_assoc_t id)
246 {
247 	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
248 	struct sctp_transport *transport;
249 	union sctp_addr *laddr = (union sctp_addr *)addr;
250 
251 	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
252 					       laddr,
253 					       &transport);
254 
255 	if (!addr_asoc)
256 		return NULL;
257 
258 	id_asoc = sctp_id2assoc(sk, id);
259 	if (id_asoc && (id_asoc != addr_asoc))
260 		return NULL;
261 
262 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
263 						(union sctp_addr *)addr);
264 
265 	return transport;
266 }
267 
268 /* API 3.1.2 bind() - UDP Style Syntax
269  * The syntax of bind() is,
270  *
271  *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
272  *
273  *   sd      - the socket descriptor returned by socket().
274  *   addr    - the address structure (struct sockaddr_in or struct
275  *             sockaddr_in6 [RFC 2553]),
276  *   addr_len - the size of the address structure.
277  */
278 SCTP_STATIC int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
279 {
280 	int retval = 0;
281 
282 	sctp_lock_sock(sk);
283 
284 	SCTP_DEBUG_PRINTK("sctp_bind(sk: %p, addr: %p, addr_len: %d)\n",
285 			  sk, addr, addr_len);
286 
287 	/* Disallow binding twice. */
288 	if (!sctp_sk(sk)->ep->base.bind_addr.port)
289 		retval = sctp_do_bind(sk, (union sctp_addr *)addr,
290 				      addr_len);
291 	else
292 		retval = -EINVAL;
293 
294 	sctp_release_sock(sk);
295 
296 	return retval;
297 }
298 
299 static long sctp_get_port_local(struct sock *, union sctp_addr *);
300 
301 /* Verify this is a valid sockaddr. */
302 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
303 					union sctp_addr *addr, int len)
304 {
305 	struct sctp_af *af;
306 
307 	/* Check minimum size.  */
308 	if (len < sizeof (struct sockaddr))
309 		return NULL;
310 
311 	/* Does this PF support this AF? */
312 	if (!opt->pf->af_supported(addr->sa.sa_family, opt))
313 		return NULL;
314 
315 	/* If we get this far, af is valid. */
316 	af = sctp_get_af_specific(addr->sa.sa_family);
317 
318 	if (len < af->sockaddr_len)
319 		return NULL;
320 
321 	return af;
322 }
323 
324 /* Bind a local address either to an endpoint or to an association.  */
325 SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
326 {
327 	struct sctp_sock *sp = sctp_sk(sk);
328 	struct sctp_endpoint *ep = sp->ep;
329 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
330 	struct sctp_af *af;
331 	unsigned short snum;
332 	int ret = 0;
333 
334 	/* Common sockaddr verification. */
335 	af = sctp_sockaddr_af(sp, addr, len);
336 	if (!af) {
337 		SCTP_DEBUG_PRINTK("sctp_do_bind(sk: %p, newaddr: %p, len: %d) EINVAL\n",
338 				  sk, addr, len);
339 		return -EINVAL;
340 	}
341 
342 	snum = ntohs(addr->v4.sin_port);
343 
344 	SCTP_DEBUG_PRINTK_IPADDR("sctp_do_bind(sk: %p, new addr: ",
345 				 ", port: %d, new port: %d, len: %d)\n",
346 				 sk,
347 				 addr,
348 				 bp->port, snum,
349 				 len);
350 
351 	/* PF specific bind() address verification. */
352 	if (!sp->pf->bind_verify(sp, addr))
353 		return -EADDRNOTAVAIL;
354 
355 	/* We must either be unbound, or bind to the same port.
356 	 * It's OK to allow 0 ports if we are already bound.
357 	 * We'll just inhert an already bound port in this case
358 	 */
359 	if (bp->port) {
360 		if (!snum)
361 			snum = bp->port;
362 		else if (snum != bp->port) {
363 			SCTP_DEBUG_PRINTK("sctp_do_bind:"
364 				  " New port %d does not match existing port "
365 				  "%d.\n", snum, bp->port);
366 			return -EINVAL;
367 		}
368 	}
369 
370 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
371 		return -EACCES;
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 		if (ret == (long) sk) {
380 			/* This endpoint has a conflicting address. */
381 			return -EINVAL;
382 		} else {
383 			return -EADDRINUSE;
384 		}
385 	}
386 
387 	/* Refresh ephemeral port.  */
388 	if (!bp->port)
389 		bp->port = inet_sk(sk)->num;
390 
391 	/* Add the address to the bind address list.
392 	 * Use GFP_ATOMIC since BHs will be disabled.
393 	 */
394 	ret = sctp_add_bind_addr(bp, addr, SCTP_ADDR_SRC, GFP_ATOMIC);
395 
396 	/* Copy back into socket for getsockname() use. */
397 	if (!ret) {
398 		inet_sk(sk)->sport = htons(inet_sk(sk)->num);
399 		af->to_sk_saddr(addr, sk);
400 	}
401 
402 	return ret;
403 }
404 
405  /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
406  *
407  * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
408  * at any one time.  If a sender, after sending an ASCONF chunk, decides
409  * it needs to transfer another ASCONF Chunk, it MUST wait until the
410  * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
411  * subsequent ASCONF. Note this restriction binds each side, so at any
412  * time two ASCONF may be in-transit on any given association (one sent
413  * from each endpoint).
414  */
415 static int sctp_send_asconf(struct sctp_association *asoc,
416 			    struct sctp_chunk *chunk)
417 {
418 	int		retval = 0;
419 
420 	/* If there is an outstanding ASCONF chunk, queue it for later
421 	 * transmission.
422 	 */
423 	if (asoc->addip_last_asconf) {
424 		list_add_tail(&chunk->list, &asoc->addip_chunk_list);
425 		goto out;
426 	}
427 
428 	/* Hold the chunk until an ASCONF_ACK is received. */
429 	sctp_chunk_hold(chunk);
430 	retval = sctp_primitive_ASCONF(asoc, chunk);
431 	if (retval)
432 		sctp_chunk_free(chunk);
433 	else
434 		asoc->addip_last_asconf = chunk;
435 
436 out:
437 	return retval;
438 }
439 
440 /* Add a list of addresses as bind addresses to local endpoint or
441  * association.
442  *
443  * Basically run through each address specified in the addrs/addrcnt
444  * array/length pair, determine if it is IPv6 or IPv4 and call
445  * sctp_do_bind() on it.
446  *
447  * If any of them fails, then the operation will be reversed and the
448  * ones that were added will be removed.
449  *
450  * Only sctp_setsockopt_bindx() is supposed to call this function.
451  */
452 static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
453 {
454 	int cnt;
455 	int retval = 0;
456 	void *addr_buf;
457 	struct sockaddr *sa_addr;
458 	struct sctp_af *af;
459 
460 	SCTP_DEBUG_PRINTK("sctp_bindx_add (sk: %p, addrs: %p, addrcnt: %d)\n",
461 			  sk, addrs, addrcnt);
462 
463 	addr_buf = addrs;
464 	for (cnt = 0; cnt < addrcnt; cnt++) {
465 		/* The list may contain either IPv4 or IPv6 address;
466 		 * determine the address length for walking thru the list.
467 		 */
468 		sa_addr = (struct sockaddr *)addr_buf;
469 		af = sctp_get_af_specific(sa_addr->sa_family);
470 		if (!af) {
471 			retval = -EINVAL;
472 			goto err_bindx_add;
473 		}
474 
475 		retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
476 				      af->sockaddr_len);
477 
478 		addr_buf += af->sockaddr_len;
479 
480 err_bindx_add:
481 		if (retval < 0) {
482 			/* Failed. Cleanup the ones that have been added */
483 			if (cnt > 0)
484 				sctp_bindx_rem(sk, addrs, cnt);
485 			return retval;
486 		}
487 	}
488 
489 	return retval;
490 }
491 
492 /* Send an ASCONF chunk with Add IP address parameters to all the peers of the
493  * associations that are part of the endpoint indicating that a list of local
494  * addresses are added to the endpoint.
495  *
496  * If any of the addresses is already in the bind address list of the
497  * association, we do not send the chunk for that association.  But it will not
498  * affect other associations.
499  *
500  * Only sctp_setsockopt_bindx() is supposed to call this function.
501  */
502 static int sctp_send_asconf_add_ip(struct sock		*sk,
503 				   struct sockaddr	*addrs,
504 				   int 			addrcnt)
505 {
506 	struct sctp_sock		*sp;
507 	struct sctp_endpoint		*ep;
508 	struct sctp_association		*asoc;
509 	struct sctp_bind_addr		*bp;
510 	struct sctp_chunk		*chunk;
511 	struct sctp_sockaddr_entry	*laddr;
512 	union sctp_addr			*addr;
513 	union sctp_addr			saveaddr;
514 	void				*addr_buf;
515 	struct sctp_af			*af;
516 	struct list_head		*pos;
517 	struct list_head		*p;
518 	int 				i;
519 	int 				retval = 0;
520 
521 	if (!sctp_addip_enable)
522 		return retval;
523 
524 	sp = sctp_sk(sk);
525 	ep = sp->ep;
526 
527 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
528 			  __FUNCTION__, sk, addrs, addrcnt);
529 
530 	list_for_each(pos, &ep->asocs) {
531 		asoc = list_entry(pos, struct sctp_association, asocs);
532 
533 		if (!asoc->peer.asconf_capable)
534 			continue;
535 
536 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
537 			continue;
538 
539 		if (!sctp_state(asoc, ESTABLISHED))
540 			continue;
541 
542 		/* Check if any address in the packed array of addresses is
543 		 * in the bind address list of the association. If so,
544 		 * do not send the asconf chunk to its peer, but continue with
545 		 * other associations.
546 		 */
547 		addr_buf = addrs;
548 		for (i = 0; i < addrcnt; i++) {
549 			addr = (union sctp_addr *)addr_buf;
550 			af = sctp_get_af_specific(addr->v4.sin_family);
551 			if (!af) {
552 				retval = -EINVAL;
553 				goto out;
554 			}
555 
556 			if (sctp_assoc_lookup_laddr(asoc, addr))
557 				break;
558 
559 			addr_buf += af->sockaddr_len;
560 		}
561 		if (i < addrcnt)
562 			continue;
563 
564 		/* Use the first valid address in bind addr list of
565 		 * association as Address Parameter of ASCONF CHUNK.
566 		 */
567 		bp = &asoc->base.bind_addr;
568 		p = bp->address_list.next;
569 		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
570 		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
571 						   addrcnt, SCTP_PARAM_ADD_IP);
572 		if (!chunk) {
573 			retval = -ENOMEM;
574 			goto out;
575 		}
576 
577 		retval = sctp_send_asconf(asoc, chunk);
578 		if (retval)
579 			goto out;
580 
581 		/* Add the new addresses to the bind address list with
582 		 * use_as_src set to 0.
583 		 */
584 		addr_buf = addrs;
585 		for (i = 0; i < addrcnt; i++) {
586 			addr = (union sctp_addr *)addr_buf;
587 			af = sctp_get_af_specific(addr->v4.sin_family);
588 			memcpy(&saveaddr, addr, af->sockaddr_len);
589 			retval = sctp_add_bind_addr(bp, &saveaddr,
590 						    SCTP_ADDR_NEW, GFP_ATOMIC);
591 			addr_buf += af->sockaddr_len;
592 		}
593 	}
594 
595 out:
596 	return retval;
597 }
598 
599 /* Remove a list of addresses from bind addresses list.  Do not remove the
600  * last address.
601  *
602  * Basically run through each address specified in the addrs/addrcnt
603  * array/length pair, determine if it is IPv6 or IPv4 and call
604  * sctp_del_bind() on it.
605  *
606  * If any of them fails, then the operation will be reversed and the
607  * ones that were removed will be added back.
608  *
609  * At least one address has to be left; if only one address is
610  * available, the operation will return -EBUSY.
611  *
612  * Only sctp_setsockopt_bindx() is supposed to call this function.
613  */
614 static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
615 {
616 	struct sctp_sock *sp = sctp_sk(sk);
617 	struct sctp_endpoint *ep = sp->ep;
618 	int cnt;
619 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
620 	int retval = 0;
621 	void *addr_buf;
622 	union sctp_addr *sa_addr;
623 	struct sctp_af *af;
624 
625 	SCTP_DEBUG_PRINTK("sctp_bindx_rem (sk: %p, addrs: %p, addrcnt: %d)\n",
626 			  sk, addrs, addrcnt);
627 
628 	addr_buf = addrs;
629 	for (cnt = 0; cnt < addrcnt; cnt++) {
630 		/* If the bind address list is empty or if there is only one
631 		 * bind address, there is nothing more to be removed (we need
632 		 * at least one address here).
633 		 */
634 		if (list_empty(&bp->address_list) ||
635 		    (sctp_list_single_entry(&bp->address_list))) {
636 			retval = -EBUSY;
637 			goto err_bindx_rem;
638 		}
639 
640 		sa_addr = (union sctp_addr *)addr_buf;
641 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
642 		if (!af) {
643 			retval = -EINVAL;
644 			goto err_bindx_rem;
645 		}
646 
647 		if (!af->addr_valid(sa_addr, sp, NULL)) {
648 			retval = -EADDRNOTAVAIL;
649 			goto err_bindx_rem;
650 		}
651 
652 		if (sa_addr->v4.sin_port != htons(bp->port)) {
653 			retval = -EINVAL;
654 			goto err_bindx_rem;
655 		}
656 
657 		/* FIXME - There is probably a need to check if sk->sk_saddr and
658 		 * sk->sk_rcv_addr are currently set to one of the addresses to
659 		 * be removed. This is something which needs to be looked into
660 		 * when we are fixing the outstanding issues with multi-homing
661 		 * socket routing and failover schemes. Refer to comments in
662 		 * sctp_do_bind(). -daisy
663 		 */
664 		retval = sctp_del_bind_addr(bp, sa_addr);
665 
666 		addr_buf += af->sockaddr_len;
667 err_bindx_rem:
668 		if (retval < 0) {
669 			/* Failed. Add the ones that has been removed back */
670 			if (cnt > 0)
671 				sctp_bindx_add(sk, addrs, cnt);
672 			return retval;
673 		}
674 	}
675 
676 	return retval;
677 }
678 
679 /* Send an ASCONF chunk with Delete IP address parameters to all the peers of
680  * the associations that are part of the endpoint indicating that a list of
681  * local addresses are removed from the endpoint.
682  *
683  * If any of the addresses is already in the bind address list of the
684  * association, we do not send the chunk for that association.  But it will not
685  * affect other associations.
686  *
687  * Only sctp_setsockopt_bindx() is supposed to call this function.
688  */
689 static int sctp_send_asconf_del_ip(struct sock		*sk,
690 				   struct sockaddr	*addrs,
691 				   int			addrcnt)
692 {
693 	struct sctp_sock	*sp;
694 	struct sctp_endpoint	*ep;
695 	struct sctp_association	*asoc;
696 	struct sctp_transport	*transport;
697 	struct sctp_bind_addr	*bp;
698 	struct sctp_chunk	*chunk;
699 	union sctp_addr		*laddr;
700 	void			*addr_buf;
701 	struct sctp_af		*af;
702 	struct list_head	*pos, *pos1;
703 	struct sctp_sockaddr_entry *saddr;
704 	int 			i;
705 	int 			retval = 0;
706 
707 	if (!sctp_addip_enable)
708 		return retval;
709 
710 	sp = sctp_sk(sk);
711 	ep = sp->ep;
712 
713 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
714 			  __FUNCTION__, sk, addrs, addrcnt);
715 
716 	list_for_each(pos, &ep->asocs) {
717 		asoc = list_entry(pos, struct sctp_association, asocs);
718 
719 		if (!asoc->peer.asconf_capable)
720 			continue;
721 
722 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
723 			continue;
724 
725 		if (!sctp_state(asoc, ESTABLISHED))
726 			continue;
727 
728 		/* Check if any address in the packed array of addresses is
729 		 * not present in the bind address list of the association.
730 		 * If so, do not send the asconf chunk to its peer, but
731 		 * continue with other associations.
732 		 */
733 		addr_buf = addrs;
734 		for (i = 0; i < addrcnt; i++) {
735 			laddr = (union sctp_addr *)addr_buf;
736 			af = sctp_get_af_specific(laddr->v4.sin_family);
737 			if (!af) {
738 				retval = -EINVAL;
739 				goto out;
740 			}
741 
742 			if (!sctp_assoc_lookup_laddr(asoc, laddr))
743 				break;
744 
745 			addr_buf += af->sockaddr_len;
746 		}
747 		if (i < addrcnt)
748 			continue;
749 
750 		/* Find one address in the association's bind address list
751 		 * that is not in the packed array of addresses. This is to
752 		 * make sure that we do not delete all the addresses in the
753 		 * association.
754 		 */
755 		bp = &asoc->base.bind_addr;
756 		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
757 					       addrcnt, sp);
758 		if (!laddr)
759 			continue;
760 
761 		/* We do not need RCU protection throughout this loop
762 		 * because this is done under a socket lock from the
763 		 * setsockopt call.
764 		 */
765 		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
766 						   SCTP_PARAM_DEL_IP);
767 		if (!chunk) {
768 			retval = -ENOMEM;
769 			goto out;
770 		}
771 
772 		/* Reset use_as_src flag for the addresses in the bind address
773 		 * list that are to be deleted.
774 		 */
775 		addr_buf = addrs;
776 		for (i = 0; i < addrcnt; i++) {
777 			laddr = (union sctp_addr *)addr_buf;
778 			af = sctp_get_af_specific(laddr->v4.sin_family);
779 			list_for_each_entry(saddr, &bp->address_list, list) {
780 				if (sctp_cmp_addr_exact(&saddr->a, laddr))
781 					saddr->state = SCTP_ADDR_DEL;
782 			}
783 			addr_buf += af->sockaddr_len;
784 		}
785 
786 		/* Update the route and saddr entries for all the transports
787 		 * as some of the addresses in the bind address list are
788 		 * about to be deleted and cannot be used as source addresses.
789 		 */
790 		list_for_each(pos1, &asoc->peer.transport_addr_list) {
791 			transport = list_entry(pos1, struct sctp_transport,
792 					       transports);
793 			dst_release(transport->dst);
794 			sctp_transport_route(transport, NULL,
795 					     sctp_sk(asoc->base.sk));
796 		}
797 
798 		retval = sctp_send_asconf(asoc, chunk);
799 	}
800 out:
801 	return retval;
802 }
803 
804 /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
805  *
806  * API 8.1
807  * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt,
808  *                int flags);
809  *
810  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
811  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
812  * or IPv6 addresses.
813  *
814  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
815  * Section 3.1.2 for this usage.
816  *
817  * addrs is a pointer to an array of one or more socket addresses. Each
818  * address is contained in its appropriate structure (i.e. struct
819  * sockaddr_in or struct sockaddr_in6) the family of the address type
820  * must be used to distinguish the address length (note that this
821  * representation is termed a "packed array" of addresses). The caller
822  * specifies the number of addresses in the array with addrcnt.
823  *
824  * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns
825  * -1, and sets errno to the appropriate error code.
826  *
827  * For SCTP, the port given in each socket address must be the same, or
828  * sctp_bindx() will fail, setting errno to EINVAL.
829  *
830  * The flags parameter is formed from the bitwise OR of zero or more of
831  * the following currently defined flags:
832  *
833  * SCTP_BINDX_ADD_ADDR
834  *
835  * SCTP_BINDX_REM_ADDR
836  *
837  * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
838  * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given
839  * addresses from the association. The two flags are mutually exclusive;
840  * if both are given, sctp_bindx() will fail with EINVAL. A caller may
841  * not remove all addresses from an association; sctp_bindx() will
842  * reject such an attempt with EINVAL.
843  *
844  * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
845  * additional addresses with an endpoint after calling bind().  Or use
846  * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
847  * socket is associated with so that no new association accepted will be
848  * associated with those addresses. If the endpoint supports dynamic
849  * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
850  * endpoint to send the appropriate message to the peer to change the
851  * peers address lists.
852  *
853  * Adding and removing addresses from a connected association is
854  * optional functionality. Implementations that do not support this
855  * functionality should return EOPNOTSUPP.
856  *
857  * Basically do nothing but copying the addresses from user to kernel
858  * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
859  * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
860  * from userspace.
861  *
862  * We don't use copy_from_user() for optimization: we first do the
863  * sanity checks (buffer size -fast- and access check-healthy
864  * pointer); if all of those succeed, then we can alloc the memory
865  * (expensive operation) needed to copy the data to kernel. Then we do
866  * the copying without checking the user space area
867  * (__copy_from_user()).
868  *
869  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
870  * it.
871  *
872  * sk        The sk of the socket
873  * addrs     The pointer to the addresses in user land
874  * addrssize Size of the addrs buffer
875  * op        Operation to perform (add or remove, see the flags of
876  *           sctp_bindx)
877  *
878  * Returns 0 if ok, <0 errno code on error.
879  */
880 SCTP_STATIC int sctp_setsockopt_bindx(struct sock* sk,
881 				      struct sockaddr __user *addrs,
882 				      int addrs_size, int op)
883 {
884 	struct sockaddr *kaddrs;
885 	int err;
886 	int addrcnt = 0;
887 	int walk_size = 0;
888 	struct sockaddr *sa_addr;
889 	void *addr_buf;
890 	struct sctp_af *af;
891 
892 	SCTP_DEBUG_PRINTK("sctp_setsocktopt_bindx: sk %p addrs %p"
893 			  " addrs_size %d opt %d\n", sk, addrs, addrs_size, op);
894 
895 	if (unlikely(addrs_size <= 0))
896 		return -EINVAL;
897 
898 	/* Check the user passed a healthy pointer.  */
899 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
900 		return -EFAULT;
901 
902 	/* Alloc space for the address array in kernel memory.  */
903 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
904 	if (unlikely(!kaddrs))
905 		return -ENOMEM;
906 
907 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
908 		kfree(kaddrs);
909 		return -EFAULT;
910 	}
911 
912 	/* Walk through the addrs buffer and count the number of addresses. */
913 	addr_buf = kaddrs;
914 	while (walk_size < addrs_size) {
915 		sa_addr = (struct sockaddr *)addr_buf;
916 		af = sctp_get_af_specific(sa_addr->sa_family);
917 
918 		/* If the address family is not supported or if this address
919 		 * causes the address buffer to overflow return EINVAL.
920 		 */
921 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
922 			kfree(kaddrs);
923 			return -EINVAL;
924 		}
925 		addrcnt++;
926 		addr_buf += af->sockaddr_len;
927 		walk_size += af->sockaddr_len;
928 	}
929 
930 	/* Do the work. */
931 	switch (op) {
932 	case SCTP_BINDX_ADD_ADDR:
933 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
934 		if (err)
935 			goto out;
936 		err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
937 		break;
938 
939 	case SCTP_BINDX_REM_ADDR:
940 		err = sctp_bindx_rem(sk, kaddrs, addrcnt);
941 		if (err)
942 			goto out;
943 		err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
944 		break;
945 
946 	default:
947 		err = -EINVAL;
948 		break;
949 	}
950 
951 out:
952 	kfree(kaddrs);
953 
954 	return err;
955 }
956 
957 /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
958  *
959  * Common routine for handling connect() and sctp_connectx().
960  * Connect will come in with just a single address.
961  */
962 static int __sctp_connect(struct sock* sk,
963 			  struct sockaddr *kaddrs,
964 			  int addrs_size)
965 {
966 	struct sctp_sock *sp;
967 	struct sctp_endpoint *ep;
968 	struct sctp_association *asoc = NULL;
969 	struct sctp_association *asoc2;
970 	struct sctp_transport *transport;
971 	union sctp_addr to;
972 	struct sctp_af *af;
973 	sctp_scope_t scope;
974 	long timeo;
975 	int err = 0;
976 	int addrcnt = 0;
977 	int walk_size = 0;
978 	union sctp_addr *sa_addr = NULL;
979 	void *addr_buf;
980 	unsigned short port;
981 	unsigned int f_flags = 0;
982 
983 	sp = sctp_sk(sk);
984 	ep = sp->ep;
985 
986 	/* connect() cannot be done on a socket that is already in ESTABLISHED
987 	 * state - UDP-style peeled off socket or a TCP-style socket that
988 	 * is already connected.
989 	 * It cannot be done even on a TCP-style listening socket.
990 	 */
991 	if (sctp_sstate(sk, ESTABLISHED) ||
992 	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
993 		err = -EISCONN;
994 		goto out_free;
995 	}
996 
997 	/* Walk through the addrs buffer and count the number of addresses. */
998 	addr_buf = kaddrs;
999 	while (walk_size < addrs_size) {
1000 		sa_addr = (union sctp_addr *)addr_buf;
1001 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
1002 		port = ntohs(sa_addr->v4.sin_port);
1003 
1004 		/* If the address family is not supported or if this address
1005 		 * causes the address buffer to overflow return EINVAL.
1006 		 */
1007 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1008 			err = -EINVAL;
1009 			goto out_free;
1010 		}
1011 
1012 		/* Save current address so we can work with it */
1013 		memcpy(&to, sa_addr, af->sockaddr_len);
1014 
1015 		err = sctp_verify_addr(sk, &to, af->sockaddr_len);
1016 		if (err)
1017 			goto out_free;
1018 
1019 		/* Make sure the destination port is correctly set
1020 		 * in all addresses.
1021 		 */
1022 		if (asoc && asoc->peer.port && asoc->peer.port != port)
1023 			goto out_free;
1024 
1025 
1026 		/* Check if there already is a matching association on the
1027 		 * endpoint (other than the one created here).
1028 		 */
1029 		asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1030 		if (asoc2 && asoc2 != asoc) {
1031 			if (asoc2->state >= SCTP_STATE_ESTABLISHED)
1032 				err = -EISCONN;
1033 			else
1034 				err = -EALREADY;
1035 			goto out_free;
1036 		}
1037 
1038 		/* If we could not find a matching association on the endpoint,
1039 		 * make sure that there is no peeled-off association matching
1040 		 * the peer address even on another socket.
1041 		 */
1042 		if (sctp_endpoint_is_peeled_off(ep, &to)) {
1043 			err = -EADDRNOTAVAIL;
1044 			goto out_free;
1045 		}
1046 
1047 		if (!asoc) {
1048 			/* If a bind() or sctp_bindx() is not called prior to
1049 			 * an sctp_connectx() call, the system picks an
1050 			 * ephemeral port and will choose an address set
1051 			 * equivalent to binding with a wildcard address.
1052 			 */
1053 			if (!ep->base.bind_addr.port) {
1054 				if (sctp_autobind(sk)) {
1055 					err = -EAGAIN;
1056 					goto out_free;
1057 				}
1058 			} else {
1059 				/*
1060 				 * If an unprivileged user inherits a 1-many
1061 				 * style socket with open associations on a
1062 				 * privileged port, it MAY be permitted to
1063 				 * accept new associations, but it SHOULD NOT
1064 				 * be permitted to open new associations.
1065 				 */
1066 				if (ep->base.bind_addr.port < PROT_SOCK &&
1067 				    !capable(CAP_NET_BIND_SERVICE)) {
1068 					err = -EACCES;
1069 					goto out_free;
1070 				}
1071 			}
1072 
1073 			scope = sctp_scope(&to);
1074 			asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1075 			if (!asoc) {
1076 				err = -ENOMEM;
1077 				goto out_free;
1078 			}
1079 		}
1080 
1081 		/* Prime the peer's transport structures.  */
1082 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL,
1083 						SCTP_UNKNOWN);
1084 		if (!transport) {
1085 			err = -ENOMEM;
1086 			goto out_free;
1087 		}
1088 
1089 		addrcnt++;
1090 		addr_buf += af->sockaddr_len;
1091 		walk_size += af->sockaddr_len;
1092 	}
1093 
1094 	err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
1095 	if (err < 0) {
1096 		goto out_free;
1097 	}
1098 
1099 	err = sctp_primitive_ASSOCIATE(asoc, NULL);
1100 	if (err < 0) {
1101 		goto out_free;
1102 	}
1103 
1104 	/* Initialize sk's dport and daddr for getpeername() */
1105 	inet_sk(sk)->dport = htons(asoc->peer.port);
1106 	af = sctp_get_af_specific(sa_addr->sa.sa_family);
1107 	af->to_sk_daddr(sa_addr, sk);
1108 	sk->sk_err = 0;
1109 
1110 	/* in-kernel sockets don't generally have a file allocated to them
1111 	 * if all they do is call sock_create_kern().
1112 	 */
1113 	if (sk->sk_socket->file)
1114 		f_flags = sk->sk_socket->file->f_flags;
1115 
1116 	timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK);
1117 
1118 	err = sctp_wait_for_connect(asoc, &timeo);
1119 
1120 	/* Don't free association on exit. */
1121 	asoc = NULL;
1122 
1123 out_free:
1124 
1125 	SCTP_DEBUG_PRINTK("About to exit __sctp_connect() free asoc: %p"
1126 			  " kaddrs: %p err: %d\n",
1127 			  asoc, kaddrs, err);
1128 	if (asoc)
1129 		sctp_association_free(asoc);
1130 	return err;
1131 }
1132 
1133 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
1134  *
1135  * API 8.9
1136  * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt);
1137  *
1138  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
1139  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
1140  * or IPv6 addresses.
1141  *
1142  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
1143  * Section 3.1.2 for this usage.
1144  *
1145  * addrs is a pointer to an array of one or more socket addresses. Each
1146  * address is contained in its appropriate structure (i.e. struct
1147  * sockaddr_in or struct sockaddr_in6) the family of the address type
1148  * must be used to distengish the address length (note that this
1149  * representation is termed a "packed array" of addresses). The caller
1150  * specifies the number of addresses in the array with addrcnt.
1151  *
1152  * On success, sctp_connectx() returns 0. On failure, sctp_connectx() returns
1153  * -1, and sets errno to the appropriate error code.
1154  *
1155  * For SCTP, the port given in each socket address must be the same, or
1156  * sctp_connectx() will fail, setting errno to EINVAL.
1157  *
1158  * An application can use sctp_connectx to initiate an association with
1159  * an endpoint that is multi-homed.  Much like sctp_bindx() this call
1160  * allows a caller to specify multiple addresses at which a peer can be
1161  * reached.  The way the SCTP stack uses the list of addresses to set up
1162  * the association is implementation dependant.  This function only
1163  * specifies that the stack will try to make use of all the addresses in
1164  * the list when needed.
1165  *
1166  * Note that the list of addresses passed in is only used for setting up
1167  * the association.  It does not necessarily equal the set of addresses
1168  * the peer uses for the resulting association.  If the caller wants to
1169  * find out the set of peer addresses, it must use sctp_getpaddrs() to
1170  * retrieve them after the association has been set up.
1171  *
1172  * Basically do nothing but copying the addresses from user to kernel
1173  * land and invoking either sctp_connectx(). This is used for tunneling
1174  * the sctp_connectx() request through sctp_setsockopt() from userspace.
1175  *
1176  * We don't use copy_from_user() for optimization: we first do the
1177  * sanity checks (buffer size -fast- and access check-healthy
1178  * pointer); if all of those succeed, then we can alloc the memory
1179  * (expensive operation) needed to copy the data to kernel. Then we do
1180  * the copying without checking the user space area
1181  * (__copy_from_user()).
1182  *
1183  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
1184  * it.
1185  *
1186  * sk        The sk of the socket
1187  * addrs     The pointer to the addresses in user land
1188  * addrssize Size of the addrs buffer
1189  *
1190  * Returns 0 if ok, <0 errno code on error.
1191  */
1192 SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
1193 				      struct sockaddr __user *addrs,
1194 				      int addrs_size)
1195 {
1196 	int err = 0;
1197 	struct sockaddr *kaddrs;
1198 
1199 	SCTP_DEBUG_PRINTK("%s - sk %p addrs %p addrs_size %d\n",
1200 			  __FUNCTION__, sk, addrs, addrs_size);
1201 
1202 	if (unlikely(addrs_size <= 0))
1203 		return -EINVAL;
1204 
1205 	/* Check the user passed a healthy pointer.  */
1206 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
1207 		return -EFAULT;
1208 
1209 	/* Alloc space for the address array in kernel memory.  */
1210 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
1211 	if (unlikely(!kaddrs))
1212 		return -ENOMEM;
1213 
1214 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
1215 		err = -EFAULT;
1216 	} else {
1217 		err = __sctp_connect(sk, kaddrs, addrs_size);
1218 	}
1219 
1220 	kfree(kaddrs);
1221 	return err;
1222 }
1223 
1224 /* API 3.1.4 close() - UDP Style Syntax
1225  * Applications use close() to perform graceful shutdown (as described in
1226  * Section 10.1 of [SCTP]) on ALL the associations currently represented
1227  * by a UDP-style socket.
1228  *
1229  * The syntax is
1230  *
1231  *   ret = close(int sd);
1232  *
1233  *   sd      - the socket descriptor of the associations to be closed.
1234  *
1235  * To gracefully shutdown a specific association represented by the
1236  * UDP-style socket, an application should use the sendmsg() call,
1237  * passing no user data, but including the appropriate flag in the
1238  * ancillary data (see Section xxxx).
1239  *
1240  * If sd in the close() call is a branched-off socket representing only
1241  * one association, the shutdown is performed on that association only.
1242  *
1243  * 4.1.6 close() - TCP Style Syntax
1244  *
1245  * Applications use close() to gracefully close down an association.
1246  *
1247  * The syntax is:
1248  *
1249  *    int close(int sd);
1250  *
1251  *      sd      - the socket descriptor of the association to be closed.
1252  *
1253  * After an application calls close() on a socket descriptor, no further
1254  * socket operations will succeed on that descriptor.
1255  *
1256  * API 7.1.4 SO_LINGER
1257  *
1258  * An application using the TCP-style socket can use this option to
1259  * perform the SCTP ABORT primitive.  The linger option structure is:
1260  *
1261  *  struct  linger {
1262  *     int     l_onoff;                // option on/off
1263  *     int     l_linger;               // linger time
1264  * };
1265  *
1266  * To enable the option, set l_onoff to 1.  If the l_linger value is set
1267  * to 0, calling close() is the same as the ABORT primitive.  If the
1268  * value is set to a negative value, the setsockopt() call will return
1269  * an error.  If the value is set to a positive value linger_time, the
1270  * close() can be blocked for at most linger_time ms.  If the graceful
1271  * shutdown phase does not finish during this period, close() will
1272  * return but the graceful shutdown phase continues in the system.
1273  */
1274 SCTP_STATIC void sctp_close(struct sock *sk, long timeout)
1275 {
1276 	struct sctp_endpoint *ep;
1277 	struct sctp_association *asoc;
1278 	struct list_head *pos, *temp;
1279 
1280 	SCTP_DEBUG_PRINTK("sctp_close(sk: 0x%p, timeout:%ld)\n", sk, timeout);
1281 
1282 	sctp_lock_sock(sk);
1283 	sk->sk_shutdown = SHUTDOWN_MASK;
1284 
1285 	ep = sctp_sk(sk)->ep;
1286 
1287 	/* Walk all associations on an endpoint.  */
1288 	list_for_each_safe(pos, temp, &ep->asocs) {
1289 		asoc = list_entry(pos, struct sctp_association, asocs);
1290 
1291 		if (sctp_style(sk, TCP)) {
1292 			/* A closed association can still be in the list if
1293 			 * it belongs to a TCP-style listening socket that is
1294 			 * not yet accepted. If so, free it. If not, send an
1295 			 * ABORT or SHUTDOWN based on the linger options.
1296 			 */
1297 			if (sctp_state(asoc, CLOSED)) {
1298 				sctp_unhash_established(asoc);
1299 				sctp_association_free(asoc);
1300 				continue;
1301 			}
1302 		}
1303 
1304 		if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
1305 			struct sctp_chunk *chunk;
1306 
1307 			chunk = sctp_make_abort_user(asoc, NULL, 0);
1308 			if (chunk)
1309 				sctp_primitive_ABORT(asoc, chunk);
1310 		} else
1311 			sctp_primitive_SHUTDOWN(asoc, NULL);
1312 	}
1313 
1314 	/* Clean up any skbs sitting on the receive queue.  */
1315 	sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
1316 	sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
1317 
1318 	/* On a TCP-style socket, block for at most linger_time if set. */
1319 	if (sctp_style(sk, TCP) && timeout)
1320 		sctp_wait_for_close(sk, timeout);
1321 
1322 	/* This will run the backlog queue.  */
1323 	sctp_release_sock(sk);
1324 
1325 	/* Supposedly, no process has access to the socket, but
1326 	 * the net layers still may.
1327 	 */
1328 	sctp_local_bh_disable();
1329 	sctp_bh_lock_sock(sk);
1330 
1331 	/* Hold the sock, since sk_common_release() will put sock_put()
1332 	 * and we have just a little more cleanup.
1333 	 */
1334 	sock_hold(sk);
1335 	sk_common_release(sk);
1336 
1337 	sctp_bh_unlock_sock(sk);
1338 	sctp_local_bh_enable();
1339 
1340 	sock_put(sk);
1341 
1342 	SCTP_DBG_OBJCNT_DEC(sock);
1343 }
1344 
1345 /* Handle EPIPE error. */
1346 static int sctp_error(struct sock *sk, int flags, int err)
1347 {
1348 	if (err == -EPIPE)
1349 		err = sock_error(sk) ? : -EPIPE;
1350 	if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
1351 		send_sig(SIGPIPE, current, 0);
1352 	return err;
1353 }
1354 
1355 /* API 3.1.3 sendmsg() - UDP Style Syntax
1356  *
1357  * An application uses sendmsg() and recvmsg() calls to transmit data to
1358  * and receive data from its peer.
1359  *
1360  *  ssize_t sendmsg(int socket, const struct msghdr *message,
1361  *                  int flags);
1362  *
1363  *  socket  - the socket descriptor of the endpoint.
1364  *  message - pointer to the msghdr structure which contains a single
1365  *            user message and possibly some ancillary data.
1366  *
1367  *            See Section 5 for complete description of the data
1368  *            structures.
1369  *
1370  *  flags   - flags sent or received with the user message, see Section
1371  *            5 for complete description of the flags.
1372  *
1373  * Note:  This function could use a rewrite especially when explicit
1374  * connect support comes in.
1375  */
1376 /* BUG:  We do not implement the equivalent of sk_stream_wait_memory(). */
1377 
1378 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
1379 
1380 SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
1381 			     struct msghdr *msg, size_t msg_len)
1382 {
1383 	struct sctp_sock *sp;
1384 	struct sctp_endpoint *ep;
1385 	struct sctp_association *new_asoc=NULL, *asoc=NULL;
1386 	struct sctp_transport *transport, *chunk_tp;
1387 	struct sctp_chunk *chunk;
1388 	union sctp_addr to;
1389 	struct sockaddr *msg_name = NULL;
1390 	struct sctp_sndrcvinfo default_sinfo = { 0 };
1391 	struct sctp_sndrcvinfo *sinfo;
1392 	struct sctp_initmsg *sinit;
1393 	sctp_assoc_t associd = 0;
1394 	sctp_cmsgs_t cmsgs = { NULL };
1395 	int err;
1396 	sctp_scope_t scope;
1397 	long timeo;
1398 	__u16 sinfo_flags = 0;
1399 	struct sctp_datamsg *datamsg;
1400 	struct list_head *pos;
1401 	int msg_flags = msg->msg_flags;
1402 
1403 	SCTP_DEBUG_PRINTK("sctp_sendmsg(sk: %p, msg: %p, msg_len: %zu)\n",
1404 			  sk, msg, msg_len);
1405 
1406 	err = 0;
1407 	sp = sctp_sk(sk);
1408 	ep = sp->ep;
1409 
1410 	SCTP_DEBUG_PRINTK("Using endpoint: %p.\n", ep);
1411 
1412 	/* We cannot send a message over a TCP-style listening socket. */
1413 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) {
1414 		err = -EPIPE;
1415 		goto out_nounlock;
1416 	}
1417 
1418 	/* Parse out the SCTP CMSGs.  */
1419 	err = sctp_msghdr_parse(msg, &cmsgs);
1420 
1421 	if (err) {
1422 		SCTP_DEBUG_PRINTK("msghdr parse err = %x\n", err);
1423 		goto out_nounlock;
1424 	}
1425 
1426 	/* Fetch the destination address for this packet.  This
1427 	 * address only selects the association--it is not necessarily
1428 	 * the address we will send to.
1429 	 * For a peeled-off socket, msg_name is ignored.
1430 	 */
1431 	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
1432 		int msg_namelen = msg->msg_namelen;
1433 
1434 		err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
1435 				       msg_namelen);
1436 		if (err)
1437 			return err;
1438 
1439 		if (msg_namelen > sizeof(to))
1440 			msg_namelen = sizeof(to);
1441 		memcpy(&to, msg->msg_name, msg_namelen);
1442 		msg_name = msg->msg_name;
1443 	}
1444 
1445 	sinfo = cmsgs.info;
1446 	sinit = cmsgs.init;
1447 
1448 	/* Did the user specify SNDRCVINFO?  */
1449 	if (sinfo) {
1450 		sinfo_flags = sinfo->sinfo_flags;
1451 		associd = sinfo->sinfo_assoc_id;
1452 	}
1453 
1454 	SCTP_DEBUG_PRINTK("msg_len: %zu, sinfo_flags: 0x%x\n",
1455 			  msg_len, sinfo_flags);
1456 
1457 	/* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */
1458 	if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) {
1459 		err = -EINVAL;
1460 		goto out_nounlock;
1461 	}
1462 
1463 	/* If SCTP_EOF is set, no data can be sent. Disallow sending zero
1464 	 * length messages when SCTP_EOF|SCTP_ABORT is not set.
1465 	 * If SCTP_ABORT is set, the message length could be non zero with
1466 	 * the msg_iov set to the user abort reason.
1467 	 */
1468 	if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) ||
1469 	    (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) {
1470 		err = -EINVAL;
1471 		goto out_nounlock;
1472 	}
1473 
1474 	/* If SCTP_ADDR_OVER is set, there must be an address
1475 	 * specified in msg_name.
1476 	 */
1477 	if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) {
1478 		err = -EINVAL;
1479 		goto out_nounlock;
1480 	}
1481 
1482 	transport = NULL;
1483 
1484 	SCTP_DEBUG_PRINTK("About to look up association.\n");
1485 
1486 	sctp_lock_sock(sk);
1487 
1488 	/* If a msg_name has been specified, assume this is to be used.  */
1489 	if (msg_name) {
1490 		/* Look for a matching association on the endpoint. */
1491 		asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1492 		if (!asoc) {
1493 			/* If we could not find a matching association on the
1494 			 * endpoint, make sure that it is not a TCP-style
1495 			 * socket that already has an association or there is
1496 			 * no peeled-off association on another socket.
1497 			 */
1498 			if ((sctp_style(sk, TCP) &&
1499 			     sctp_sstate(sk, ESTABLISHED)) ||
1500 			    sctp_endpoint_is_peeled_off(ep, &to)) {
1501 				err = -EADDRNOTAVAIL;
1502 				goto out_unlock;
1503 			}
1504 		}
1505 	} else {
1506 		asoc = sctp_id2assoc(sk, associd);
1507 		if (!asoc) {
1508 			err = -EPIPE;
1509 			goto out_unlock;
1510 		}
1511 	}
1512 
1513 	if (asoc) {
1514 		SCTP_DEBUG_PRINTK("Just looked up association: %p.\n", asoc);
1515 
1516 		/* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED
1517 		 * socket that has an association in CLOSED state. This can
1518 		 * happen when an accepted socket has an association that is
1519 		 * already CLOSED.
1520 		 */
1521 		if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) {
1522 			err = -EPIPE;
1523 			goto out_unlock;
1524 		}
1525 
1526 		if (sinfo_flags & SCTP_EOF) {
1527 			SCTP_DEBUG_PRINTK("Shutting down association: %p\n",
1528 					  asoc);
1529 			sctp_primitive_SHUTDOWN(asoc, NULL);
1530 			err = 0;
1531 			goto out_unlock;
1532 		}
1533 		if (sinfo_flags & SCTP_ABORT) {
1534 
1535 			chunk = sctp_make_abort_user(asoc, msg, msg_len);
1536 			if (!chunk) {
1537 				err = -ENOMEM;
1538 				goto out_unlock;
1539 			}
1540 
1541 			SCTP_DEBUG_PRINTK("Aborting association: %p\n", asoc);
1542 			sctp_primitive_ABORT(asoc, chunk);
1543 			err = 0;
1544 			goto out_unlock;
1545 		}
1546 	}
1547 
1548 	/* Do we need to create the association?  */
1549 	if (!asoc) {
1550 		SCTP_DEBUG_PRINTK("There is no association yet.\n");
1551 
1552 		if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) {
1553 			err = -EINVAL;
1554 			goto out_unlock;
1555 		}
1556 
1557 		/* Check for invalid stream against the stream counts,
1558 		 * either the default or the user specified stream counts.
1559 		 */
1560 		if (sinfo) {
1561 			if (!sinit || (sinit && !sinit->sinit_num_ostreams)) {
1562 				/* Check against the defaults. */
1563 				if (sinfo->sinfo_stream >=
1564 				    sp->initmsg.sinit_num_ostreams) {
1565 					err = -EINVAL;
1566 					goto out_unlock;
1567 				}
1568 			} else {
1569 				/* Check against the requested.  */
1570 				if (sinfo->sinfo_stream >=
1571 				    sinit->sinit_num_ostreams) {
1572 					err = -EINVAL;
1573 					goto out_unlock;
1574 				}
1575 			}
1576 		}
1577 
1578 		/*
1579 		 * API 3.1.2 bind() - UDP Style Syntax
1580 		 * If a bind() or sctp_bindx() is not called prior to a
1581 		 * sendmsg() call that initiates a new association, the
1582 		 * system picks an ephemeral port and will choose an address
1583 		 * set equivalent to binding with a wildcard address.
1584 		 */
1585 		if (!ep->base.bind_addr.port) {
1586 			if (sctp_autobind(sk)) {
1587 				err = -EAGAIN;
1588 				goto out_unlock;
1589 			}
1590 		} else {
1591 			/*
1592 			 * If an unprivileged user inherits a one-to-many
1593 			 * style socket with open associations on a privileged
1594 			 * port, it MAY be permitted to accept new associations,
1595 			 * but it SHOULD NOT be permitted to open new
1596 			 * associations.
1597 			 */
1598 			if (ep->base.bind_addr.port < PROT_SOCK &&
1599 			    !capable(CAP_NET_BIND_SERVICE)) {
1600 				err = -EACCES;
1601 				goto out_unlock;
1602 			}
1603 		}
1604 
1605 		scope = sctp_scope(&to);
1606 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1607 		if (!new_asoc) {
1608 			err = -ENOMEM;
1609 			goto out_unlock;
1610 		}
1611 		asoc = new_asoc;
1612 
1613 		/* If the SCTP_INIT ancillary data is specified, set all
1614 		 * the association init values accordingly.
1615 		 */
1616 		if (sinit) {
1617 			if (sinit->sinit_num_ostreams) {
1618 				asoc->c.sinit_num_ostreams =
1619 					sinit->sinit_num_ostreams;
1620 			}
1621 			if (sinit->sinit_max_instreams) {
1622 				asoc->c.sinit_max_instreams =
1623 					sinit->sinit_max_instreams;
1624 			}
1625 			if (sinit->sinit_max_attempts) {
1626 				asoc->max_init_attempts
1627 					= sinit->sinit_max_attempts;
1628 			}
1629 			if (sinit->sinit_max_init_timeo) {
1630 				asoc->max_init_timeo =
1631 				 msecs_to_jiffies(sinit->sinit_max_init_timeo);
1632 			}
1633 		}
1634 
1635 		/* Prime the peer's transport structures.  */
1636 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN);
1637 		if (!transport) {
1638 			err = -ENOMEM;
1639 			goto out_free;
1640 		}
1641 		err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
1642 		if (err < 0) {
1643 			err = -ENOMEM;
1644 			goto out_free;
1645 		}
1646 	}
1647 
1648 	/* ASSERT: we have a valid association at this point.  */
1649 	SCTP_DEBUG_PRINTK("We have a valid association.\n");
1650 
1651 	if (!sinfo) {
1652 		/* If the user didn't specify SNDRCVINFO, make up one with
1653 		 * some defaults.
1654 		 */
1655 		default_sinfo.sinfo_stream = asoc->default_stream;
1656 		default_sinfo.sinfo_flags = asoc->default_flags;
1657 		default_sinfo.sinfo_ppid = asoc->default_ppid;
1658 		default_sinfo.sinfo_context = asoc->default_context;
1659 		default_sinfo.sinfo_timetolive = asoc->default_timetolive;
1660 		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
1661 		sinfo = &default_sinfo;
1662 	}
1663 
1664 	/* API 7.1.7, the sndbuf size per association bounds the
1665 	 * maximum size of data that can be sent in a single send call.
1666 	 */
1667 	if (msg_len > sk->sk_sndbuf) {
1668 		err = -EMSGSIZE;
1669 		goto out_free;
1670 	}
1671 
1672 	if (asoc->pmtu_pending)
1673 		sctp_assoc_pending_pmtu(asoc);
1674 
1675 	/* If fragmentation is disabled and the message length exceeds the
1676 	 * association fragmentation point, return EMSGSIZE.  The I-D
1677 	 * does not specify what this error is, but this looks like
1678 	 * a great fit.
1679 	 */
1680 	if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
1681 		err = -EMSGSIZE;
1682 		goto out_free;
1683 	}
1684 
1685 	if (sinfo) {
1686 		/* Check for invalid stream. */
1687 		if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) {
1688 			err = -EINVAL;
1689 			goto out_free;
1690 		}
1691 	}
1692 
1693 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1694 	if (!sctp_wspace(asoc)) {
1695 		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
1696 		if (err)
1697 			goto out_free;
1698 	}
1699 
1700 	/* If an address is passed with the sendto/sendmsg call, it is used
1701 	 * to override the primary destination address in the TCP model, or
1702 	 * when SCTP_ADDR_OVER flag is set in the UDP model.
1703 	 */
1704 	if ((sctp_style(sk, TCP) && msg_name) ||
1705 	    (sinfo_flags & SCTP_ADDR_OVER)) {
1706 		chunk_tp = sctp_assoc_lookup_paddr(asoc, &to);
1707 		if (!chunk_tp) {
1708 			err = -EINVAL;
1709 			goto out_free;
1710 		}
1711 	} else
1712 		chunk_tp = NULL;
1713 
1714 	/* Auto-connect, if we aren't connected already. */
1715 	if (sctp_state(asoc, CLOSED)) {
1716 		err = sctp_primitive_ASSOCIATE(asoc, NULL);
1717 		if (err < 0)
1718 			goto out_free;
1719 		SCTP_DEBUG_PRINTK("We associated primitively.\n");
1720 	}
1721 
1722 	/* Break the message into multiple chunks of maximum size. */
1723 	datamsg = sctp_datamsg_from_user(asoc, sinfo, msg, msg_len);
1724 	if (!datamsg) {
1725 		err = -ENOMEM;
1726 		goto out_free;
1727 	}
1728 
1729 	/* Now send the (possibly) fragmented message. */
1730 	list_for_each(pos, &datamsg->chunks) {
1731 		chunk = list_entry(pos, struct sctp_chunk, frag_list);
1732 		sctp_datamsg_track(chunk);
1733 
1734 		/* Do accounting for the write space.  */
1735 		sctp_set_owner_w(chunk);
1736 
1737 		chunk->transport = chunk_tp;
1738 
1739 		/* Send it to the lower layers.  Note:  all chunks
1740 		 * must either fail or succeed.   The lower layer
1741 		 * works that way today.  Keep it that way or this
1742 		 * breaks.
1743 		 */
1744 		err = sctp_primitive_SEND(asoc, chunk);
1745 		/* Did the lower layer accept the chunk? */
1746 		if (err)
1747 			sctp_chunk_free(chunk);
1748 		SCTP_DEBUG_PRINTK("We sent primitively.\n");
1749 	}
1750 
1751 	sctp_datamsg_free(datamsg);
1752 	if (err)
1753 		goto out_free;
1754 	else
1755 		err = msg_len;
1756 
1757 	/* If we are already past ASSOCIATE, the lower
1758 	 * layers are responsible for association cleanup.
1759 	 */
1760 	goto out_unlock;
1761 
1762 out_free:
1763 	if (new_asoc)
1764 		sctp_association_free(asoc);
1765 out_unlock:
1766 	sctp_release_sock(sk);
1767 
1768 out_nounlock:
1769 	return sctp_error(sk, msg_flags, err);
1770 
1771 #if 0
1772 do_sock_err:
1773 	if (msg_len)
1774 		err = msg_len;
1775 	else
1776 		err = sock_error(sk);
1777 	goto out;
1778 
1779 do_interrupted:
1780 	if (msg_len)
1781 		err = msg_len;
1782 	goto out;
1783 #endif /* 0 */
1784 }
1785 
1786 /* This is an extended version of skb_pull() that removes the data from the
1787  * start of a skb even when data is spread across the list of skb's in the
1788  * frag_list. len specifies the total amount of data that needs to be removed.
1789  * when 'len' bytes could be removed from the skb, it returns 0.
1790  * If 'len' exceeds the total skb length,  it returns the no. of bytes that
1791  * could not be removed.
1792  */
1793 static int sctp_skb_pull(struct sk_buff *skb, int len)
1794 {
1795 	struct sk_buff *list;
1796 	int skb_len = skb_headlen(skb);
1797 	int rlen;
1798 
1799 	if (len <= skb_len) {
1800 		__skb_pull(skb, len);
1801 		return 0;
1802 	}
1803 	len -= skb_len;
1804 	__skb_pull(skb, skb_len);
1805 
1806 	for (list = skb_shinfo(skb)->frag_list; list; list = list->next) {
1807 		rlen = sctp_skb_pull(list, len);
1808 		skb->len -= (len-rlen);
1809 		skb->data_len -= (len-rlen);
1810 
1811 		if (!rlen)
1812 			return 0;
1813 
1814 		len = rlen;
1815 	}
1816 
1817 	return len;
1818 }
1819 
1820 /* API 3.1.3  recvmsg() - UDP Style Syntax
1821  *
1822  *  ssize_t recvmsg(int socket, struct msghdr *message,
1823  *                    int flags);
1824  *
1825  *  socket  - the socket descriptor of the endpoint.
1826  *  message - pointer to the msghdr structure which contains a single
1827  *            user message and possibly some ancillary data.
1828  *
1829  *            See Section 5 for complete description of the data
1830  *            structures.
1831  *
1832  *  flags   - flags sent or received with the user message, see Section
1833  *            5 for complete description of the flags.
1834  */
1835 static struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);
1836 
1837 SCTP_STATIC int sctp_recvmsg(struct kiocb *iocb, struct sock *sk,
1838 			     struct msghdr *msg, size_t len, int noblock,
1839 			     int flags, int *addr_len)
1840 {
1841 	struct sctp_ulpevent *event = NULL;
1842 	struct sctp_sock *sp = sctp_sk(sk);
1843 	struct sk_buff *skb;
1844 	int copied;
1845 	int err = 0;
1846 	int skb_len;
1847 
1848 	SCTP_DEBUG_PRINTK("sctp_recvmsg(%s: %p, %s: %p, %s: %zd, %s: %d, %s: "
1849 			  "0x%x, %s: %p)\n", "sk", sk, "msghdr", msg,
1850 			  "len", len, "knoblauch", noblock,
1851 			  "flags", flags, "addr_len", addr_len);
1852 
1853 	sctp_lock_sock(sk);
1854 
1855 	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED)) {
1856 		err = -ENOTCONN;
1857 		goto out;
1858 	}
1859 
1860 	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
1861 	if (!skb)
1862 		goto out;
1863 
1864 	/* Get the total length of the skb including any skb's in the
1865 	 * frag_list.
1866 	 */
1867 	skb_len = skb->len;
1868 
1869 	copied = skb_len;
1870 	if (copied > len)
1871 		copied = len;
1872 
1873 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1874 
1875 	event = sctp_skb2event(skb);
1876 
1877 	if (err)
1878 		goto out_free;
1879 
1880 	sock_recv_timestamp(msg, sk, skb);
1881 	if (sctp_ulpevent_is_notification(event)) {
1882 		msg->msg_flags |= MSG_NOTIFICATION;
1883 		sp->pf->event_msgname(event, msg->msg_name, addr_len);
1884 	} else {
1885 		sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
1886 	}
1887 
1888 	/* Check if we allow SCTP_SNDRCVINFO. */
1889 	if (sp->subscribe.sctp_data_io_event)
1890 		sctp_ulpevent_read_sndrcvinfo(event, msg);
1891 #if 0
1892 	/* FIXME: we should be calling IP/IPv6 layers.  */
1893 	if (sk->sk_protinfo.af_inet.cmsg_flags)
1894 		ip_cmsg_recv(msg, skb);
1895 #endif
1896 
1897 	err = copied;
1898 
1899 	/* If skb's length exceeds the user's buffer, update the skb and
1900 	 * push it back to the receive_queue so that the next call to
1901 	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
1902 	 */
1903 	if (skb_len > copied) {
1904 		msg->msg_flags &= ~MSG_EOR;
1905 		if (flags & MSG_PEEK)
1906 			goto out_free;
1907 		sctp_skb_pull(skb, copied);
1908 		skb_queue_head(&sk->sk_receive_queue, skb);
1909 
1910 		/* When only partial message is copied to the user, increase
1911 		 * rwnd by that amount. If all the data in the skb is read,
1912 		 * rwnd is updated when the event is freed.
1913 		 */
1914 		sctp_assoc_rwnd_increase(event->asoc, copied);
1915 		goto out;
1916 	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
1917 		   (event->msg_flags & MSG_EOR))
1918 		msg->msg_flags |= MSG_EOR;
1919 	else
1920 		msg->msg_flags &= ~MSG_EOR;
1921 
1922 out_free:
1923 	if (flags & MSG_PEEK) {
1924 		/* Release the skb reference acquired after peeking the skb in
1925 		 * sctp_skb_recv_datagram().
1926 		 */
1927 		kfree_skb(skb);
1928 	} else {
1929 		/* Free the event which includes releasing the reference to
1930 		 * the owner of the skb, freeing the skb and updating the
1931 		 * rwnd.
1932 		 */
1933 		sctp_ulpevent_free(event);
1934 	}
1935 out:
1936 	sctp_release_sock(sk);
1937 	return err;
1938 }
1939 
1940 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
1941  *
1942  * This option is a on/off flag.  If enabled no SCTP message
1943  * fragmentation will be performed.  Instead if a message being sent
1944  * exceeds the current PMTU size, the message will NOT be sent and
1945  * instead a error will be indicated to the user.
1946  */
1947 static int sctp_setsockopt_disable_fragments(struct sock *sk,
1948 					    char __user *optval, int optlen)
1949 {
1950 	int val;
1951 
1952 	if (optlen < sizeof(int))
1953 		return -EINVAL;
1954 
1955 	if (get_user(val, (int __user *)optval))
1956 		return -EFAULT;
1957 
1958 	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
1959 
1960 	return 0;
1961 }
1962 
1963 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
1964 					int optlen)
1965 {
1966 	if (optlen != sizeof(struct sctp_event_subscribe))
1967 		return -EINVAL;
1968 	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
1969 		return -EFAULT;
1970 	return 0;
1971 }
1972 
1973 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
1974  *
1975  * This socket option is applicable to the UDP-style socket only.  When
1976  * set it will cause associations that are idle for more than the
1977  * specified number of seconds to automatically close.  An association
1978  * being idle is defined an association that has NOT sent or received
1979  * user data.  The special value of '0' indicates that no automatic
1980  * close of any associations should be performed.  The option expects an
1981  * integer defining the number of seconds of idle time before an
1982  * association is closed.
1983  */
1984 static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
1985 					    int optlen)
1986 {
1987 	struct sctp_sock *sp = sctp_sk(sk);
1988 
1989 	/* Applicable to UDP-style socket only */
1990 	if (sctp_style(sk, TCP))
1991 		return -EOPNOTSUPP;
1992 	if (optlen != sizeof(int))
1993 		return -EINVAL;
1994 	if (copy_from_user(&sp->autoclose, optval, optlen))
1995 		return -EFAULT;
1996 
1997 	return 0;
1998 }
1999 
2000 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
2001  *
2002  * Applications can enable or disable heartbeats for any peer address of
2003  * an association, modify an address's heartbeat interval, force a
2004  * heartbeat to be sent immediately, and adjust the address's maximum
2005  * number of retransmissions sent before an address is considered
2006  * unreachable.  The following structure is used to access and modify an
2007  * address's parameters:
2008  *
2009  *  struct sctp_paddrparams {
2010  *     sctp_assoc_t            spp_assoc_id;
2011  *     struct sockaddr_storage spp_address;
2012  *     uint32_t                spp_hbinterval;
2013  *     uint16_t                spp_pathmaxrxt;
2014  *     uint32_t                spp_pathmtu;
2015  *     uint32_t                spp_sackdelay;
2016  *     uint32_t                spp_flags;
2017  * };
2018  *
2019  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
2020  *                     application, and identifies the association for
2021  *                     this query.
2022  *   spp_address     - This specifies which address is of interest.
2023  *   spp_hbinterval  - This contains the value of the heartbeat interval,
2024  *                     in milliseconds.  If a  value of zero
2025  *                     is present in this field then no changes are to
2026  *                     be made to this parameter.
2027  *   spp_pathmaxrxt  - This contains the maximum number of
2028  *                     retransmissions before this address shall be
2029  *                     considered unreachable. If a  value of zero
2030  *                     is present in this field then no changes are to
2031  *                     be made to this parameter.
2032  *   spp_pathmtu     - When Path MTU discovery is disabled the value
2033  *                     specified here will be the "fixed" path mtu.
2034  *                     Note that if the spp_address field is empty
2035  *                     then all associations on this address will
2036  *                     have this fixed path mtu set upon them.
2037  *
2038  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
2039  *                     the number of milliseconds that sacks will be delayed
2040  *                     for. This value will apply to all addresses of an
2041  *                     association if the spp_address field is empty. Note
2042  *                     also, that if delayed sack is enabled and this
2043  *                     value is set to 0, no change is made to the last
2044  *                     recorded delayed sack timer value.
2045  *
2046  *   spp_flags       - These flags are used to control various features
2047  *                     on an association. The flag field may contain
2048  *                     zero or more of the following options.
2049  *
2050  *                     SPP_HB_ENABLE  - Enable heartbeats on the
2051  *                     specified address. Note that if the address
2052  *                     field is empty all addresses for the association
2053  *                     have heartbeats enabled upon them.
2054  *
2055  *                     SPP_HB_DISABLE - Disable heartbeats on the
2056  *                     speicifed address. Note that if the address
2057  *                     field is empty all addresses for the association
2058  *                     will have their heartbeats disabled. Note also
2059  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
2060  *                     mutually exclusive, only one of these two should
2061  *                     be specified. Enabling both fields will have
2062  *                     undetermined results.
2063  *
2064  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
2065  *                     to be made immediately.
2066  *
2067  *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
2068  *                     heartbeat delayis to be set to the value of 0
2069  *                     milliseconds.
2070  *
2071  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
2072  *                     discovery upon the specified address. Note that
2073  *                     if the address feild is empty then all addresses
2074  *                     on the association are effected.
2075  *
2076  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
2077  *                     discovery upon the specified address. Note that
2078  *                     if the address feild is empty then all addresses
2079  *                     on the association are effected. Not also that
2080  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
2081  *                     exclusive. Enabling both will have undetermined
2082  *                     results.
2083  *
2084  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
2085  *                     on delayed sack. The time specified in spp_sackdelay
2086  *                     is used to specify the sack delay for this address. Note
2087  *                     that if spp_address is empty then all addresses will
2088  *                     enable delayed sack and take on the sack delay
2089  *                     value specified in spp_sackdelay.
2090  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
2091  *                     off delayed sack. If the spp_address field is blank then
2092  *                     delayed sack is disabled for the entire association. Note
2093  *                     also that this field is mutually exclusive to
2094  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
2095  *                     results.
2096  */
2097 static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
2098 				       struct sctp_transport   *trans,
2099 				       struct sctp_association *asoc,
2100 				       struct sctp_sock        *sp,
2101 				       int                      hb_change,
2102 				       int                      pmtud_change,
2103 				       int                      sackdelay_change)
2104 {
2105 	int error;
2106 
2107 	if (params->spp_flags & SPP_HB_DEMAND && trans) {
2108 		error = sctp_primitive_REQUESTHEARTBEAT (trans->asoc, trans);
2109 		if (error)
2110 			return error;
2111 	}
2112 
2113 	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
2114 	 * this field is ignored.  Note also that a value of zero indicates
2115 	 * the current setting should be left unchanged.
2116 	 */
2117 	if (params->spp_flags & SPP_HB_ENABLE) {
2118 
2119 		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
2120 		 * set.  This lets us use 0 value when this flag
2121 		 * is set.
2122 		 */
2123 		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
2124 			params->spp_hbinterval = 0;
2125 
2126 		if (params->spp_hbinterval ||
2127 		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
2128 			if (trans) {
2129 				trans->hbinterval =
2130 				    msecs_to_jiffies(params->spp_hbinterval);
2131 			} else if (asoc) {
2132 				asoc->hbinterval =
2133 				    msecs_to_jiffies(params->spp_hbinterval);
2134 			} else {
2135 				sp->hbinterval = params->spp_hbinterval;
2136 			}
2137 		}
2138 	}
2139 
2140 	if (hb_change) {
2141 		if (trans) {
2142 			trans->param_flags =
2143 				(trans->param_flags & ~SPP_HB) | hb_change;
2144 		} else if (asoc) {
2145 			asoc->param_flags =
2146 				(asoc->param_flags & ~SPP_HB) | hb_change;
2147 		} else {
2148 			sp->param_flags =
2149 				(sp->param_flags & ~SPP_HB) | hb_change;
2150 		}
2151 	}
2152 
2153 	/* When Path MTU discovery is disabled the value specified here will
2154 	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
2155 	 * include the flag SPP_PMTUD_DISABLE for this field to have any
2156 	 * effect).
2157 	 */
2158 	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
2159 		if (trans) {
2160 			trans->pathmtu = params->spp_pathmtu;
2161 			sctp_assoc_sync_pmtu(asoc);
2162 		} else if (asoc) {
2163 			asoc->pathmtu = params->spp_pathmtu;
2164 			sctp_frag_point(sp, params->spp_pathmtu);
2165 		} else {
2166 			sp->pathmtu = params->spp_pathmtu;
2167 		}
2168 	}
2169 
2170 	if (pmtud_change) {
2171 		if (trans) {
2172 			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
2173 				(params->spp_flags & SPP_PMTUD_ENABLE);
2174 			trans->param_flags =
2175 				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
2176 			if (update) {
2177 				sctp_transport_pmtu(trans);
2178 				sctp_assoc_sync_pmtu(asoc);
2179 			}
2180 		} else if (asoc) {
2181 			asoc->param_flags =
2182 				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
2183 		} else {
2184 			sp->param_flags =
2185 				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
2186 		}
2187 	}
2188 
2189 	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
2190 	 * value of this field is ignored.  Note also that a value of zero
2191 	 * indicates the current setting should be left unchanged.
2192 	 */
2193 	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
2194 		if (trans) {
2195 			trans->sackdelay =
2196 				msecs_to_jiffies(params->spp_sackdelay);
2197 		} else if (asoc) {
2198 			asoc->sackdelay =
2199 				msecs_to_jiffies(params->spp_sackdelay);
2200 		} else {
2201 			sp->sackdelay = params->spp_sackdelay;
2202 		}
2203 	}
2204 
2205 	if (sackdelay_change) {
2206 		if (trans) {
2207 			trans->param_flags =
2208 				(trans->param_flags & ~SPP_SACKDELAY) |
2209 				sackdelay_change;
2210 		} else if (asoc) {
2211 			asoc->param_flags =
2212 				(asoc->param_flags & ~SPP_SACKDELAY) |
2213 				sackdelay_change;
2214 		} else {
2215 			sp->param_flags =
2216 				(sp->param_flags & ~SPP_SACKDELAY) |
2217 				sackdelay_change;
2218 		}
2219 	}
2220 
2221 	/* Note that unless the spp_flag is set to SPP_PMTUD_ENABLE the value
2222 	 * of this field is ignored.  Note also that a value of zero
2223 	 * indicates the current setting should be left unchanged.
2224 	 */
2225 	if ((params->spp_flags & SPP_PMTUD_ENABLE) && params->spp_pathmaxrxt) {
2226 		if (trans) {
2227 			trans->pathmaxrxt = params->spp_pathmaxrxt;
2228 		} else if (asoc) {
2229 			asoc->pathmaxrxt = params->spp_pathmaxrxt;
2230 		} else {
2231 			sp->pathmaxrxt = params->spp_pathmaxrxt;
2232 		}
2233 	}
2234 
2235 	return 0;
2236 }
2237 
2238 static int sctp_setsockopt_peer_addr_params(struct sock *sk,
2239 					    char __user *optval, int optlen)
2240 {
2241 	struct sctp_paddrparams  params;
2242 	struct sctp_transport   *trans = NULL;
2243 	struct sctp_association *asoc = NULL;
2244 	struct sctp_sock        *sp = sctp_sk(sk);
2245 	int error;
2246 	int hb_change, pmtud_change, sackdelay_change;
2247 
2248 	if (optlen != sizeof(struct sctp_paddrparams))
2249 		return - EINVAL;
2250 
2251 	if (copy_from_user(&params, optval, optlen))
2252 		return -EFAULT;
2253 
2254 	/* Validate flags and value parameters. */
2255 	hb_change        = params.spp_flags & SPP_HB;
2256 	pmtud_change     = params.spp_flags & SPP_PMTUD;
2257 	sackdelay_change = params.spp_flags & SPP_SACKDELAY;
2258 
2259 	if (hb_change        == SPP_HB ||
2260 	    pmtud_change     == SPP_PMTUD ||
2261 	    sackdelay_change == SPP_SACKDELAY ||
2262 	    params.spp_sackdelay > 500 ||
2263 	    (params.spp_pathmtu
2264 	    && params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
2265 		return -EINVAL;
2266 
2267 	/* If an address other than INADDR_ANY is specified, and
2268 	 * no transport is found, then the request is invalid.
2269 	 */
2270 	if (!sctp_is_any(( union sctp_addr *)&params.spp_address)) {
2271 		trans = sctp_addr_id2transport(sk, &params.spp_address,
2272 					       params.spp_assoc_id);
2273 		if (!trans)
2274 			return -EINVAL;
2275 	}
2276 
2277 	/* Get association, if assoc_id != 0 and the socket is a one
2278 	 * to many style socket, and an association was not found, then
2279 	 * the id was invalid.
2280 	 */
2281 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
2282 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
2283 		return -EINVAL;
2284 
2285 	/* Heartbeat demand can only be sent on a transport or
2286 	 * association, but not a socket.
2287 	 */
2288 	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
2289 		return -EINVAL;
2290 
2291 	/* Process parameters. */
2292 	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2293 					    hb_change, pmtud_change,
2294 					    sackdelay_change);
2295 
2296 	if (error)
2297 		return error;
2298 
2299 	/* If changes are for association, also apply parameters to each
2300 	 * transport.
2301 	 */
2302 	if (!trans && asoc) {
2303 		struct list_head *pos;
2304 
2305 		list_for_each(pos, &asoc->peer.transport_addr_list) {
2306 			trans = list_entry(pos, struct sctp_transport,
2307 					   transports);
2308 			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2309 						    hb_change, pmtud_change,
2310 						    sackdelay_change);
2311 		}
2312 	}
2313 
2314 	return 0;
2315 }
2316 
2317 /* 7.1.23. Delayed Ack Timer (SCTP_DELAYED_ACK_TIME)
2318  *
2319  *   This options will get or set the delayed ack timer.  The time is set
2320  *   in milliseconds.  If the assoc_id is 0, then this sets or gets the
2321  *   endpoints default delayed ack timer value.  If the assoc_id field is
2322  *   non-zero, then the set or get effects the specified association.
2323  *
2324  *   struct sctp_assoc_value {
2325  *       sctp_assoc_t            assoc_id;
2326  *       uint32_t                assoc_value;
2327  *   };
2328  *
2329  *     assoc_id    - This parameter, indicates which association the
2330  *                   user is preforming an action upon. Note that if
2331  *                   this field's value is zero then the endpoints
2332  *                   default value is changed (effecting future
2333  *                   associations only).
2334  *
2335  *     assoc_value - This parameter contains the number of milliseconds
2336  *                   that the user is requesting the delayed ACK timer
2337  *                   be set to. Note that this value is defined in
2338  *                   the standard to be between 200 and 500 milliseconds.
2339  *
2340  *                   Note: a value of zero will leave the value alone,
2341  *                   but disable SACK delay. A non-zero value will also
2342  *                   enable SACK delay.
2343  */
2344 
2345 static int sctp_setsockopt_delayed_ack_time(struct sock *sk,
2346 					    char __user *optval, int optlen)
2347 {
2348 	struct sctp_assoc_value  params;
2349 	struct sctp_transport   *trans = NULL;
2350 	struct sctp_association *asoc = NULL;
2351 	struct sctp_sock        *sp = sctp_sk(sk);
2352 
2353 	if (optlen != sizeof(struct sctp_assoc_value))
2354 		return - EINVAL;
2355 
2356 	if (copy_from_user(&params, optval, optlen))
2357 		return -EFAULT;
2358 
2359 	/* Validate value parameter. */
2360 	if (params.assoc_value > 500)
2361 		return -EINVAL;
2362 
2363 	/* Get association, if assoc_id != 0 and the socket is a one
2364 	 * to many style socket, and an association was not found, then
2365 	 * the id was invalid.
2366 	 */
2367 	asoc = sctp_id2assoc(sk, params.assoc_id);
2368 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
2369 		return -EINVAL;
2370 
2371 	if (params.assoc_value) {
2372 		if (asoc) {
2373 			asoc->sackdelay =
2374 				msecs_to_jiffies(params.assoc_value);
2375 			asoc->param_flags =
2376 				(asoc->param_flags & ~SPP_SACKDELAY) |
2377 				SPP_SACKDELAY_ENABLE;
2378 		} else {
2379 			sp->sackdelay = params.assoc_value;
2380 			sp->param_flags =
2381 				(sp->param_flags & ~SPP_SACKDELAY) |
2382 				SPP_SACKDELAY_ENABLE;
2383 		}
2384 	} else {
2385 		if (asoc) {
2386 			asoc->param_flags =
2387 				(asoc->param_flags & ~SPP_SACKDELAY) |
2388 				SPP_SACKDELAY_DISABLE;
2389 		} else {
2390 			sp->param_flags =
2391 				(sp->param_flags & ~SPP_SACKDELAY) |
2392 				SPP_SACKDELAY_DISABLE;
2393 		}
2394 	}
2395 
2396 	/* If change is for association, also apply to each transport. */
2397 	if (asoc) {
2398 		struct list_head *pos;
2399 
2400 		list_for_each(pos, &asoc->peer.transport_addr_list) {
2401 			trans = list_entry(pos, struct sctp_transport,
2402 					   transports);
2403 			if (params.assoc_value) {
2404 				trans->sackdelay =
2405 					msecs_to_jiffies(params.assoc_value);
2406 				trans->param_flags =
2407 					(trans->param_flags & ~SPP_SACKDELAY) |
2408 					SPP_SACKDELAY_ENABLE;
2409 			} else {
2410 				trans->param_flags =
2411 					(trans->param_flags & ~SPP_SACKDELAY) |
2412 					SPP_SACKDELAY_DISABLE;
2413 			}
2414 		}
2415 	}
2416 
2417 	return 0;
2418 }
2419 
2420 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
2421  *
2422  * Applications can specify protocol parameters for the default association
2423  * initialization.  The option name argument to setsockopt() and getsockopt()
2424  * is SCTP_INITMSG.
2425  *
2426  * Setting initialization parameters is effective only on an unconnected
2427  * socket (for UDP-style sockets only future associations are effected
2428  * by the change).  With TCP-style sockets, this option is inherited by
2429  * sockets derived from a listener socket.
2430  */
2431 static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, int optlen)
2432 {
2433 	struct sctp_initmsg sinit;
2434 	struct sctp_sock *sp = sctp_sk(sk);
2435 
2436 	if (optlen != sizeof(struct sctp_initmsg))
2437 		return -EINVAL;
2438 	if (copy_from_user(&sinit, optval, optlen))
2439 		return -EFAULT;
2440 
2441 	if (sinit.sinit_num_ostreams)
2442 		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
2443 	if (sinit.sinit_max_instreams)
2444 		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
2445 	if (sinit.sinit_max_attempts)
2446 		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
2447 	if (sinit.sinit_max_init_timeo)
2448 		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
2449 
2450 	return 0;
2451 }
2452 
2453 /*
2454  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
2455  *
2456  *   Applications that wish to use the sendto() system call may wish to
2457  *   specify a default set of parameters that would normally be supplied
2458  *   through the inclusion of ancillary data.  This socket option allows
2459  *   such an application to set the default sctp_sndrcvinfo structure.
2460  *   The application that wishes to use this socket option simply passes
2461  *   in to this call the sctp_sndrcvinfo structure defined in Section
2462  *   5.2.2) The input parameters accepted by this call include
2463  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
2464  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
2465  *   to this call if the caller is using the UDP model.
2466  */
2467 static int sctp_setsockopt_default_send_param(struct sock *sk,
2468 						char __user *optval, int optlen)
2469 {
2470 	struct sctp_sndrcvinfo info;
2471 	struct sctp_association *asoc;
2472 	struct sctp_sock *sp = sctp_sk(sk);
2473 
2474 	if (optlen != sizeof(struct sctp_sndrcvinfo))
2475 		return -EINVAL;
2476 	if (copy_from_user(&info, optval, optlen))
2477 		return -EFAULT;
2478 
2479 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
2480 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
2481 		return -EINVAL;
2482 
2483 	if (asoc) {
2484 		asoc->default_stream = info.sinfo_stream;
2485 		asoc->default_flags = info.sinfo_flags;
2486 		asoc->default_ppid = info.sinfo_ppid;
2487 		asoc->default_context = info.sinfo_context;
2488 		asoc->default_timetolive = info.sinfo_timetolive;
2489 	} else {
2490 		sp->default_stream = info.sinfo_stream;
2491 		sp->default_flags = info.sinfo_flags;
2492 		sp->default_ppid = info.sinfo_ppid;
2493 		sp->default_context = info.sinfo_context;
2494 		sp->default_timetolive = info.sinfo_timetolive;
2495 	}
2496 
2497 	return 0;
2498 }
2499 
2500 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
2501  *
2502  * Requests that the local SCTP stack use the enclosed peer address as
2503  * the association primary.  The enclosed address must be one of the
2504  * association peer's addresses.
2505  */
2506 static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
2507 					int optlen)
2508 {
2509 	struct sctp_prim prim;
2510 	struct sctp_transport *trans;
2511 
2512 	if (optlen != sizeof(struct sctp_prim))
2513 		return -EINVAL;
2514 
2515 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
2516 		return -EFAULT;
2517 
2518 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
2519 	if (!trans)
2520 		return -EINVAL;
2521 
2522 	sctp_assoc_set_primary(trans->asoc, trans);
2523 
2524 	return 0;
2525 }
2526 
2527 /*
2528  * 7.1.5 SCTP_NODELAY
2529  *
2530  * Turn on/off any Nagle-like algorithm.  This means that packets are
2531  * generally sent as soon as possible and no unnecessary delays are
2532  * introduced, at the cost of more packets in the network.  Expects an
2533  *  integer boolean flag.
2534  */
2535 static int sctp_setsockopt_nodelay(struct sock *sk, char __user *optval,
2536 					int optlen)
2537 {
2538 	int val;
2539 
2540 	if (optlen < sizeof(int))
2541 		return -EINVAL;
2542 	if (get_user(val, (int __user *)optval))
2543 		return -EFAULT;
2544 
2545 	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
2546 	return 0;
2547 }
2548 
2549 /*
2550  *
2551  * 7.1.1 SCTP_RTOINFO
2552  *
2553  * The protocol parameters used to initialize and bound retransmission
2554  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
2555  * and modify these parameters.
2556  * All parameters are time values, in milliseconds.  A value of 0, when
2557  * modifying the parameters, indicates that the current value should not
2558  * be changed.
2559  *
2560  */
2561 static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, int optlen) {
2562 	struct sctp_rtoinfo rtoinfo;
2563 	struct sctp_association *asoc;
2564 
2565 	if (optlen != sizeof (struct sctp_rtoinfo))
2566 		return -EINVAL;
2567 
2568 	if (copy_from_user(&rtoinfo, optval, optlen))
2569 		return -EFAULT;
2570 
2571 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
2572 
2573 	/* Set the values to the specific association */
2574 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
2575 		return -EINVAL;
2576 
2577 	if (asoc) {
2578 		if (rtoinfo.srto_initial != 0)
2579 			asoc->rto_initial =
2580 				msecs_to_jiffies(rtoinfo.srto_initial);
2581 		if (rtoinfo.srto_max != 0)
2582 			asoc->rto_max = msecs_to_jiffies(rtoinfo.srto_max);
2583 		if (rtoinfo.srto_min != 0)
2584 			asoc->rto_min = msecs_to_jiffies(rtoinfo.srto_min);
2585 	} else {
2586 		/* If there is no association or the association-id = 0
2587 		 * set the values to the endpoint.
2588 		 */
2589 		struct sctp_sock *sp = sctp_sk(sk);
2590 
2591 		if (rtoinfo.srto_initial != 0)
2592 			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
2593 		if (rtoinfo.srto_max != 0)
2594 			sp->rtoinfo.srto_max = rtoinfo.srto_max;
2595 		if (rtoinfo.srto_min != 0)
2596 			sp->rtoinfo.srto_min = rtoinfo.srto_min;
2597 	}
2598 
2599 	return 0;
2600 }
2601 
2602 /*
2603  *
2604  * 7.1.2 SCTP_ASSOCINFO
2605  *
2606  * This option is used to tune the maximum retransmission attempts
2607  * of the association.
2608  * Returns an error if the new association retransmission value is
2609  * greater than the sum of the retransmission value  of the peer.
2610  * See [SCTP] for more information.
2611  *
2612  */
2613 static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, int optlen)
2614 {
2615 
2616 	struct sctp_assocparams assocparams;
2617 	struct sctp_association *asoc;
2618 
2619 	if (optlen != sizeof(struct sctp_assocparams))
2620 		return -EINVAL;
2621 	if (copy_from_user(&assocparams, optval, optlen))
2622 		return -EFAULT;
2623 
2624 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
2625 
2626 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
2627 		return -EINVAL;
2628 
2629 	/* Set the values to the specific association */
2630 	if (asoc) {
2631 		if (assocparams.sasoc_asocmaxrxt != 0) {
2632 			__u32 path_sum = 0;
2633 			int   paths = 0;
2634 			struct list_head *pos;
2635 			struct sctp_transport *peer_addr;
2636 
2637 			list_for_each(pos, &asoc->peer.transport_addr_list) {
2638 				peer_addr = list_entry(pos,
2639 						struct sctp_transport,
2640 						transports);
2641 				path_sum += peer_addr->pathmaxrxt;
2642 				paths++;
2643 			}
2644 
2645 			/* Only validate asocmaxrxt if we have more then
2646 			 * one path/transport.  We do this because path
2647 			 * retransmissions are only counted when we have more
2648 			 * then one path.
2649 			 */
2650 			if (paths > 1 &&
2651 			    assocparams.sasoc_asocmaxrxt > path_sum)
2652 				return -EINVAL;
2653 
2654 			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
2655 		}
2656 
2657 		if (assocparams.sasoc_cookie_life != 0) {
2658 			asoc->cookie_life.tv_sec =
2659 					assocparams.sasoc_cookie_life / 1000;
2660 			asoc->cookie_life.tv_usec =
2661 					(assocparams.sasoc_cookie_life % 1000)
2662 					* 1000;
2663 		}
2664 	} else {
2665 		/* Set the values to the endpoint */
2666 		struct sctp_sock *sp = sctp_sk(sk);
2667 
2668 		if (assocparams.sasoc_asocmaxrxt != 0)
2669 			sp->assocparams.sasoc_asocmaxrxt =
2670 						assocparams.sasoc_asocmaxrxt;
2671 		if (assocparams.sasoc_cookie_life != 0)
2672 			sp->assocparams.sasoc_cookie_life =
2673 						assocparams.sasoc_cookie_life;
2674 	}
2675 	return 0;
2676 }
2677 
2678 /*
2679  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
2680  *
2681  * This socket option is a boolean flag which turns on or off mapped V4
2682  * addresses.  If this option is turned on and the socket is type
2683  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
2684  * If this option is turned off, then no mapping will be done of V4
2685  * addresses and a user will receive both PF_INET6 and PF_INET type
2686  * addresses on the socket.
2687  */
2688 static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, int optlen)
2689 {
2690 	int val;
2691 	struct sctp_sock *sp = sctp_sk(sk);
2692 
2693 	if (optlen < sizeof(int))
2694 		return -EINVAL;
2695 	if (get_user(val, (int __user *)optval))
2696 		return -EFAULT;
2697 	if (val)
2698 		sp->v4mapped = 1;
2699 	else
2700 		sp->v4mapped = 0;
2701 
2702 	return 0;
2703 }
2704 
2705 /*
2706  * 7.1.17 Set the maximum fragrmentation size (SCTP_MAXSEG)
2707  *
2708  * This socket option specifies the maximum size to put in any outgoing
2709  * SCTP chunk.  If a message is larger than this size it will be
2710  * fragmented by SCTP into the specified size.  Note that the underlying
2711  * SCTP implementation may fragment into smaller sized chunks when the
2712  * PMTU of the underlying association is smaller than the value set by
2713  * the user.
2714  */
2715 static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, int optlen)
2716 {
2717 	struct sctp_association *asoc;
2718 	struct list_head *pos;
2719 	struct sctp_sock *sp = sctp_sk(sk);
2720 	int val;
2721 
2722 	if (optlen < sizeof(int))
2723 		return -EINVAL;
2724 	if (get_user(val, (int __user *)optval))
2725 		return -EFAULT;
2726 	if ((val != 0) && ((val < 8) || (val > SCTP_MAX_CHUNK_LEN)))
2727 		return -EINVAL;
2728 	sp->user_frag = val;
2729 
2730 	/* Update the frag_point of the existing associations. */
2731 	list_for_each(pos, &(sp->ep->asocs)) {
2732 		asoc = list_entry(pos, struct sctp_association, asocs);
2733 		asoc->frag_point = sctp_frag_point(sp, asoc->pathmtu);
2734 	}
2735 
2736 	return 0;
2737 }
2738 
2739 
2740 /*
2741  *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
2742  *
2743  *   Requests that the peer mark the enclosed address as the association
2744  *   primary. The enclosed address must be one of the association's
2745  *   locally bound addresses. The following structure is used to make a
2746  *   set primary request:
2747  */
2748 static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
2749 					     int optlen)
2750 {
2751 	struct sctp_sock	*sp;
2752 	struct sctp_endpoint	*ep;
2753 	struct sctp_association	*asoc = NULL;
2754 	struct sctp_setpeerprim	prim;
2755 	struct sctp_chunk	*chunk;
2756 	int 			err;
2757 
2758 	sp = sctp_sk(sk);
2759 	ep = sp->ep;
2760 
2761 	if (!sctp_addip_enable)
2762 		return -EPERM;
2763 
2764 	if (optlen != sizeof(struct sctp_setpeerprim))
2765 		return -EINVAL;
2766 
2767 	if (copy_from_user(&prim, optval, optlen))
2768 		return -EFAULT;
2769 
2770 	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
2771 	if (!asoc)
2772 		return -EINVAL;
2773 
2774 	if (!asoc->peer.asconf_capable)
2775 		return -EPERM;
2776 
2777 	if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
2778 		return -EPERM;
2779 
2780 	if (!sctp_state(asoc, ESTABLISHED))
2781 		return -ENOTCONN;
2782 
2783 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
2784 		return -EADDRNOTAVAIL;
2785 
2786 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
2787 	chunk = sctp_make_asconf_set_prim(asoc,
2788 					  (union sctp_addr *)&prim.sspp_addr);
2789 	if (!chunk)
2790 		return -ENOMEM;
2791 
2792 	err = sctp_send_asconf(asoc, chunk);
2793 
2794 	SCTP_DEBUG_PRINTK("We set peer primary addr primitively.\n");
2795 
2796 	return err;
2797 }
2798 
2799 static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
2800 					  int optlen)
2801 {
2802 	struct sctp_setadaptation adaptation;
2803 
2804 	if (optlen != sizeof(struct sctp_setadaptation))
2805 		return -EINVAL;
2806 	if (copy_from_user(&adaptation, optval, optlen))
2807 		return -EFAULT;
2808 
2809 	sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
2810 
2811 	return 0;
2812 }
2813 
2814 /*
2815  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
2816  *
2817  * The context field in the sctp_sndrcvinfo structure is normally only
2818  * used when a failed message is retrieved holding the value that was
2819  * sent down on the actual send call.  This option allows the setting of
2820  * a default context on an association basis that will be received on
2821  * reading messages from the peer.  This is especially helpful in the
2822  * one-2-many model for an application to keep some reference to an
2823  * internal state machine that is processing messages on the
2824  * association.  Note that the setting of this value only effects
2825  * received messages from the peer and does not effect the value that is
2826  * saved with outbound messages.
2827  */
2828 static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
2829 				   int optlen)
2830 {
2831 	struct sctp_assoc_value params;
2832 	struct sctp_sock *sp;
2833 	struct sctp_association *asoc;
2834 
2835 	if (optlen != sizeof(struct sctp_assoc_value))
2836 		return -EINVAL;
2837 	if (copy_from_user(&params, optval, optlen))
2838 		return -EFAULT;
2839 
2840 	sp = sctp_sk(sk);
2841 
2842 	if (params.assoc_id != 0) {
2843 		asoc = sctp_id2assoc(sk, params.assoc_id);
2844 		if (!asoc)
2845 			return -EINVAL;
2846 		asoc->default_rcv_context = params.assoc_value;
2847 	} else {
2848 		sp->default_rcv_context = params.assoc_value;
2849 	}
2850 
2851 	return 0;
2852 }
2853 
2854 /*
2855  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
2856  *
2857  * This options will at a minimum specify if the implementation is doing
2858  * fragmented interleave.  Fragmented interleave, for a one to many
2859  * socket, is when subsequent calls to receive a message may return
2860  * parts of messages from different associations.  Some implementations
2861  * may allow you to turn this value on or off.  If so, when turned off,
2862  * no fragment interleave will occur (which will cause a head of line
2863  * blocking amongst multiple associations sharing the same one to many
2864  * socket).  When this option is turned on, then each receive call may
2865  * come from a different association (thus the user must receive data
2866  * with the extended calls (e.g. sctp_recvmsg) to keep track of which
2867  * association each receive belongs to.
2868  *
2869  * This option takes a boolean value.  A non-zero value indicates that
2870  * fragmented interleave is on.  A value of zero indicates that
2871  * fragmented interleave is off.
2872  *
2873  * Note that it is important that an implementation that allows this
2874  * option to be turned on, have it off by default.  Otherwise an unaware
2875  * application using the one to many model may become confused and act
2876  * incorrectly.
2877  */
2878 static int sctp_setsockopt_fragment_interleave(struct sock *sk,
2879 					       char __user *optval,
2880 					       int optlen)
2881 {
2882 	int val;
2883 
2884 	if (optlen != sizeof(int))
2885 		return -EINVAL;
2886 	if (get_user(val, (int __user *)optval))
2887 		return -EFAULT;
2888 
2889 	sctp_sk(sk)->frag_interleave = (val == 0) ? 0 : 1;
2890 
2891 	return 0;
2892 }
2893 
2894 /*
2895  * 7.1.25.  Set or Get the sctp partial delivery point
2896  *       (SCTP_PARTIAL_DELIVERY_POINT)
2897  * This option will set or get the SCTP partial delivery point.  This
2898  * point is the size of a message where the partial delivery API will be
2899  * invoked to help free up rwnd space for the peer.  Setting this to a
2900  * lower value will cause partial delivery's to happen more often.  The
2901  * calls argument is an integer that sets or gets the partial delivery
2902  * point.
2903  */
2904 static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
2905 						  char __user *optval,
2906 						  int optlen)
2907 {
2908 	u32 val;
2909 
2910 	if (optlen != sizeof(u32))
2911 		return -EINVAL;
2912 	if (get_user(val, (int __user *)optval))
2913 		return -EFAULT;
2914 
2915 	sctp_sk(sk)->pd_point = val;
2916 
2917 	return 0; /* is this the right error code? */
2918 }
2919 
2920 /*
2921  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
2922  *
2923  * This option will allow a user to change the maximum burst of packets
2924  * that can be emitted by this association.  Note that the default value
2925  * is 4, and some implementations may restrict this setting so that it
2926  * can only be lowered.
2927  *
2928  * NOTE: This text doesn't seem right.  Do this on a socket basis with
2929  * future associations inheriting the socket value.
2930  */
2931 static int sctp_setsockopt_maxburst(struct sock *sk,
2932 				    char __user *optval,
2933 				    int optlen)
2934 {
2935 	int val;
2936 
2937 	if (optlen != sizeof(int))
2938 		return -EINVAL;
2939 	if (get_user(val, (int __user *)optval))
2940 		return -EFAULT;
2941 
2942 	if (val < 0)
2943 		return -EINVAL;
2944 
2945 	sctp_sk(sk)->max_burst = val;
2946 
2947 	return 0;
2948 }
2949 
2950 /*
2951  * 7.1.18.  Add a chunk that must be authenticated (SCTP_AUTH_CHUNK)
2952  *
2953  * This set option adds a chunk type that the user is requesting to be
2954  * received only in an authenticated way.  Changes to the list of chunks
2955  * will only effect future associations on the socket.
2956  */
2957 static int sctp_setsockopt_auth_chunk(struct sock *sk,
2958 				    char __user *optval,
2959 				    int optlen)
2960 {
2961 	struct sctp_authchunk val;
2962 
2963 	if (optlen != sizeof(struct sctp_authchunk))
2964 		return -EINVAL;
2965 	if (copy_from_user(&val, optval, optlen))
2966 		return -EFAULT;
2967 
2968 	switch (val.sauth_chunk) {
2969 		case SCTP_CID_INIT:
2970 		case SCTP_CID_INIT_ACK:
2971 		case SCTP_CID_SHUTDOWN_COMPLETE:
2972 		case SCTP_CID_AUTH:
2973 			return -EINVAL;
2974 	}
2975 
2976 	/* add this chunk id to the endpoint */
2977 	return sctp_auth_ep_add_chunkid(sctp_sk(sk)->ep, val.sauth_chunk);
2978 }
2979 
2980 /*
2981  * 7.1.19.  Get or set the list of supported HMAC Identifiers (SCTP_HMAC_IDENT)
2982  *
2983  * This option gets or sets the list of HMAC algorithms that the local
2984  * endpoint requires the peer to use.
2985  */
2986 static int sctp_setsockopt_hmac_ident(struct sock *sk,
2987 				    char __user *optval,
2988 				    int optlen)
2989 {
2990 	struct sctp_hmacalgo *hmacs;
2991 	int err;
2992 
2993 	if (optlen < sizeof(struct sctp_hmacalgo))
2994 		return -EINVAL;
2995 
2996 	hmacs = kmalloc(optlen, GFP_KERNEL);
2997 	if (!hmacs)
2998 		return -ENOMEM;
2999 
3000 	if (copy_from_user(hmacs, optval, optlen)) {
3001 		err = -EFAULT;
3002 		goto out;
3003 	}
3004 
3005 	if (hmacs->shmac_num_idents == 0 ||
3006 	    hmacs->shmac_num_idents > SCTP_AUTH_NUM_HMACS) {
3007 		err = -EINVAL;
3008 		goto out;
3009 	}
3010 
3011 	err = sctp_auth_ep_set_hmacs(sctp_sk(sk)->ep, hmacs);
3012 out:
3013 	kfree(hmacs);
3014 	return err;
3015 }
3016 
3017 /*
3018  * 7.1.20.  Set a shared key (SCTP_AUTH_KEY)
3019  *
3020  * This option will set a shared secret key which is used to build an
3021  * association shared key.
3022  */
3023 static int sctp_setsockopt_auth_key(struct sock *sk,
3024 				    char __user *optval,
3025 				    int optlen)
3026 {
3027 	struct sctp_authkey *authkey;
3028 	struct sctp_association *asoc;
3029 	int ret;
3030 
3031 	if (optlen <= sizeof(struct sctp_authkey))
3032 		return -EINVAL;
3033 
3034 	authkey = kmalloc(optlen, GFP_KERNEL);
3035 	if (!authkey)
3036 		return -ENOMEM;
3037 
3038 	if (copy_from_user(authkey, optval, optlen)) {
3039 		ret = -EFAULT;
3040 		goto out;
3041 	}
3042 
3043 	asoc = sctp_id2assoc(sk, authkey->sca_assoc_id);
3044 	if (!asoc && authkey->sca_assoc_id && sctp_style(sk, UDP)) {
3045 		ret = -EINVAL;
3046 		goto out;
3047 	}
3048 
3049 	ret = sctp_auth_set_key(sctp_sk(sk)->ep, asoc, authkey);
3050 out:
3051 	kfree(authkey);
3052 	return ret;
3053 }
3054 
3055 /*
3056  * 7.1.21.  Get or set the active shared key (SCTP_AUTH_ACTIVE_KEY)
3057  *
3058  * This option will get or set the active shared key to be used to build
3059  * the association shared key.
3060  */
3061 static int sctp_setsockopt_active_key(struct sock *sk,
3062 					char __user *optval,
3063 					int optlen)
3064 {
3065 	struct sctp_authkeyid val;
3066 	struct sctp_association *asoc;
3067 
3068 	if (optlen != sizeof(struct sctp_authkeyid))
3069 		return -EINVAL;
3070 	if (copy_from_user(&val, optval, optlen))
3071 		return -EFAULT;
3072 
3073 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3074 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3075 		return -EINVAL;
3076 
3077 	return sctp_auth_set_active_key(sctp_sk(sk)->ep, asoc,
3078 					val.scact_keynumber);
3079 }
3080 
3081 /*
3082  * 7.1.22.  Delete a shared key (SCTP_AUTH_DELETE_KEY)
3083  *
3084  * This set option will delete a shared secret key from use.
3085  */
3086 static int sctp_setsockopt_del_key(struct sock *sk,
3087 					char __user *optval,
3088 					int optlen)
3089 {
3090 	struct sctp_authkeyid val;
3091 	struct sctp_association *asoc;
3092 
3093 	if (optlen != sizeof(struct sctp_authkeyid))
3094 		return -EINVAL;
3095 	if (copy_from_user(&val, optval, optlen))
3096 		return -EFAULT;
3097 
3098 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3099 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3100 		return -EINVAL;
3101 
3102 	return sctp_auth_del_key_id(sctp_sk(sk)->ep, asoc,
3103 				    val.scact_keynumber);
3104 
3105 }
3106 
3107 
3108 /* API 6.2 setsockopt(), getsockopt()
3109  *
3110  * Applications use setsockopt() and getsockopt() to set or retrieve
3111  * socket options.  Socket options are used to change the default
3112  * behavior of sockets calls.  They are described in Section 7.
3113  *
3114  * The syntax is:
3115  *
3116  *   ret = getsockopt(int sd, int level, int optname, void __user *optval,
3117  *                    int __user *optlen);
3118  *   ret = setsockopt(int sd, int level, int optname, const void __user *optval,
3119  *                    int optlen);
3120  *
3121  *   sd      - the socket descript.
3122  *   level   - set to IPPROTO_SCTP for all SCTP options.
3123  *   optname - the option name.
3124  *   optval  - the buffer to store the value of the option.
3125  *   optlen  - the size of the buffer.
3126  */
3127 SCTP_STATIC int sctp_setsockopt(struct sock *sk, int level, int optname,
3128 				char __user *optval, int optlen)
3129 {
3130 	int retval = 0;
3131 
3132 	SCTP_DEBUG_PRINTK("sctp_setsockopt(sk: %p... optname: %d)\n",
3133 			  sk, optname);
3134 
3135 	/* I can hardly begin to describe how wrong this is.  This is
3136 	 * so broken as to be worse than useless.  The API draft
3137 	 * REALLY is NOT helpful here...  I am not convinced that the
3138 	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
3139 	 * are at all well-founded.
3140 	 */
3141 	if (level != SOL_SCTP) {
3142 		struct sctp_af *af = sctp_sk(sk)->pf->af;
3143 		retval = af->setsockopt(sk, level, optname, optval, optlen);
3144 		goto out_nounlock;
3145 	}
3146 
3147 	sctp_lock_sock(sk);
3148 
3149 	switch (optname) {
3150 	case SCTP_SOCKOPT_BINDX_ADD:
3151 		/* 'optlen' is the size of the addresses buffer. */
3152 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3153 					       optlen, SCTP_BINDX_ADD_ADDR);
3154 		break;
3155 
3156 	case SCTP_SOCKOPT_BINDX_REM:
3157 		/* 'optlen' is the size of the addresses buffer. */
3158 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3159 					       optlen, SCTP_BINDX_REM_ADDR);
3160 		break;
3161 
3162 	case SCTP_SOCKOPT_CONNECTX:
3163 		/* 'optlen' is the size of the addresses buffer. */
3164 		retval = sctp_setsockopt_connectx(sk, (struct sockaddr __user *)optval,
3165 					       optlen);
3166 		break;
3167 
3168 	case SCTP_DISABLE_FRAGMENTS:
3169 		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
3170 		break;
3171 
3172 	case SCTP_EVENTS:
3173 		retval = sctp_setsockopt_events(sk, optval, optlen);
3174 		break;
3175 
3176 	case SCTP_AUTOCLOSE:
3177 		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
3178 		break;
3179 
3180 	case SCTP_PEER_ADDR_PARAMS:
3181 		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
3182 		break;
3183 
3184 	case SCTP_DELAYED_ACK_TIME:
3185 		retval = sctp_setsockopt_delayed_ack_time(sk, optval, optlen);
3186 		break;
3187 	case SCTP_PARTIAL_DELIVERY_POINT:
3188 		retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
3189 		break;
3190 
3191 	case SCTP_INITMSG:
3192 		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
3193 		break;
3194 	case SCTP_DEFAULT_SEND_PARAM:
3195 		retval = sctp_setsockopt_default_send_param(sk, optval,
3196 							    optlen);
3197 		break;
3198 	case SCTP_PRIMARY_ADDR:
3199 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
3200 		break;
3201 	case SCTP_SET_PEER_PRIMARY_ADDR:
3202 		retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
3203 		break;
3204 	case SCTP_NODELAY:
3205 		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
3206 		break;
3207 	case SCTP_RTOINFO:
3208 		retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
3209 		break;
3210 	case SCTP_ASSOCINFO:
3211 		retval = sctp_setsockopt_associnfo(sk, optval, optlen);
3212 		break;
3213 	case SCTP_I_WANT_MAPPED_V4_ADDR:
3214 		retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
3215 		break;
3216 	case SCTP_MAXSEG:
3217 		retval = sctp_setsockopt_maxseg(sk, optval, optlen);
3218 		break;
3219 	case SCTP_ADAPTATION_LAYER:
3220 		retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
3221 		break;
3222 	case SCTP_CONTEXT:
3223 		retval = sctp_setsockopt_context(sk, optval, optlen);
3224 		break;
3225 	case SCTP_FRAGMENT_INTERLEAVE:
3226 		retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
3227 		break;
3228 	case SCTP_MAX_BURST:
3229 		retval = sctp_setsockopt_maxburst(sk, optval, optlen);
3230 		break;
3231 	case SCTP_AUTH_CHUNK:
3232 		retval = sctp_setsockopt_auth_chunk(sk, optval, optlen);
3233 		break;
3234 	case SCTP_HMAC_IDENT:
3235 		retval = sctp_setsockopt_hmac_ident(sk, optval, optlen);
3236 		break;
3237 	case SCTP_AUTH_KEY:
3238 		retval = sctp_setsockopt_auth_key(sk, optval, optlen);
3239 		break;
3240 	case SCTP_AUTH_ACTIVE_KEY:
3241 		retval = sctp_setsockopt_active_key(sk, optval, optlen);
3242 		break;
3243 	case SCTP_AUTH_DELETE_KEY:
3244 		retval = sctp_setsockopt_del_key(sk, optval, optlen);
3245 		break;
3246 	default:
3247 		retval = -ENOPROTOOPT;
3248 		break;
3249 	}
3250 
3251 	sctp_release_sock(sk);
3252 
3253 out_nounlock:
3254 	return retval;
3255 }
3256 
3257 /* API 3.1.6 connect() - UDP Style Syntax
3258  *
3259  * An application may use the connect() call in the UDP model to initiate an
3260  * association without sending data.
3261  *
3262  * The syntax is:
3263  *
3264  * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
3265  *
3266  * sd: the socket descriptor to have a new association added to.
3267  *
3268  * nam: the address structure (either struct sockaddr_in or struct
3269  *    sockaddr_in6 defined in RFC2553 [7]).
3270  *
3271  * len: the size of the address.
3272  */
3273 SCTP_STATIC int sctp_connect(struct sock *sk, struct sockaddr *addr,
3274 			     int addr_len)
3275 {
3276 	int err = 0;
3277 	struct sctp_af *af;
3278 
3279 	sctp_lock_sock(sk);
3280 
3281 	SCTP_DEBUG_PRINTK("%s - sk: %p, sockaddr: %p, addr_len: %d\n",
3282 			  __FUNCTION__, sk, addr, addr_len);
3283 
3284 	/* Validate addr_len before calling common connect/connectx routine. */
3285 	af = sctp_get_af_specific(addr->sa_family);
3286 	if (!af || addr_len < af->sockaddr_len) {
3287 		err = -EINVAL;
3288 	} else {
3289 		/* Pass correct addr len to common routine (so it knows there
3290 		 * is only one address being passed.
3291 		 */
3292 		err = __sctp_connect(sk, addr, af->sockaddr_len);
3293 	}
3294 
3295 	sctp_release_sock(sk);
3296 	return err;
3297 }
3298 
3299 /* FIXME: Write comments. */
3300 SCTP_STATIC int sctp_disconnect(struct sock *sk, int flags)
3301 {
3302 	return -EOPNOTSUPP; /* STUB */
3303 }
3304 
3305 /* 4.1.4 accept() - TCP Style Syntax
3306  *
3307  * Applications use accept() call to remove an established SCTP
3308  * association from the accept queue of the endpoint.  A new socket
3309  * descriptor will be returned from accept() to represent the newly
3310  * formed association.
3311  */
3312 SCTP_STATIC struct sock *sctp_accept(struct sock *sk, int flags, int *err)
3313 {
3314 	struct sctp_sock *sp;
3315 	struct sctp_endpoint *ep;
3316 	struct sock *newsk = NULL;
3317 	struct sctp_association *asoc;
3318 	long timeo;
3319 	int error = 0;
3320 
3321 	sctp_lock_sock(sk);
3322 
3323 	sp = sctp_sk(sk);
3324 	ep = sp->ep;
3325 
3326 	if (!sctp_style(sk, TCP)) {
3327 		error = -EOPNOTSUPP;
3328 		goto out;
3329 	}
3330 
3331 	if (!sctp_sstate(sk, LISTENING)) {
3332 		error = -EINVAL;
3333 		goto out;
3334 	}
3335 
3336 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
3337 
3338 	error = sctp_wait_for_accept(sk, timeo);
3339 	if (error)
3340 		goto out;
3341 
3342 	/* We treat the list of associations on the endpoint as the accept
3343 	 * queue and pick the first association on the list.
3344 	 */
3345 	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
3346 
3347 	newsk = sp->pf->create_accept_sk(sk, asoc);
3348 	if (!newsk) {
3349 		error = -ENOMEM;
3350 		goto out;
3351 	}
3352 
3353 	/* Populate the fields of the newsk from the oldsk and migrate the
3354 	 * asoc to the newsk.
3355 	 */
3356 	sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
3357 
3358 out:
3359 	sctp_release_sock(sk);
3360 	*err = error;
3361 	return newsk;
3362 }
3363 
3364 /* The SCTP ioctl handler. */
3365 SCTP_STATIC int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
3366 {
3367 	return -ENOIOCTLCMD;
3368 }
3369 
3370 /* This is the function which gets called during socket creation to
3371  * initialized the SCTP-specific portion of the sock.
3372  * The sock structure should already be zero-filled memory.
3373  */
3374 SCTP_STATIC int sctp_init_sock(struct sock *sk)
3375 {
3376 	struct sctp_endpoint *ep;
3377 	struct sctp_sock *sp;
3378 
3379 	SCTP_DEBUG_PRINTK("sctp_init_sock(sk: %p)\n", sk);
3380 
3381 	sp = sctp_sk(sk);
3382 
3383 	/* Initialize the SCTP per socket area.  */
3384 	switch (sk->sk_type) {
3385 	case SOCK_SEQPACKET:
3386 		sp->type = SCTP_SOCKET_UDP;
3387 		break;
3388 	case SOCK_STREAM:
3389 		sp->type = SCTP_SOCKET_TCP;
3390 		break;
3391 	default:
3392 		return -ESOCKTNOSUPPORT;
3393 	}
3394 
3395 	/* Initialize default send parameters. These parameters can be
3396 	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
3397 	 */
3398 	sp->default_stream = 0;
3399 	sp->default_ppid = 0;
3400 	sp->default_flags = 0;
3401 	sp->default_context = 0;
3402 	sp->default_timetolive = 0;
3403 
3404 	sp->default_rcv_context = 0;
3405 	sp->max_burst = sctp_max_burst;
3406 
3407 	/* Initialize default setup parameters. These parameters
3408 	 * can be modified with the SCTP_INITMSG socket option or
3409 	 * overridden by the SCTP_INIT CMSG.
3410 	 */
3411 	sp->initmsg.sinit_num_ostreams   = sctp_max_outstreams;
3412 	sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
3413 	sp->initmsg.sinit_max_attempts   = sctp_max_retrans_init;
3414 	sp->initmsg.sinit_max_init_timeo = sctp_rto_max;
3415 
3416 	/* Initialize default RTO related parameters.  These parameters can
3417 	 * be modified for with the SCTP_RTOINFO socket option.
3418 	 */
3419 	sp->rtoinfo.srto_initial = sctp_rto_initial;
3420 	sp->rtoinfo.srto_max     = sctp_rto_max;
3421 	sp->rtoinfo.srto_min     = sctp_rto_min;
3422 
3423 	/* Initialize default association related parameters. These parameters
3424 	 * can be modified with the SCTP_ASSOCINFO socket option.
3425 	 */
3426 	sp->assocparams.sasoc_asocmaxrxt = sctp_max_retrans_association;
3427 	sp->assocparams.sasoc_number_peer_destinations = 0;
3428 	sp->assocparams.sasoc_peer_rwnd = 0;
3429 	sp->assocparams.sasoc_local_rwnd = 0;
3430 	sp->assocparams.sasoc_cookie_life = sctp_valid_cookie_life;
3431 
3432 	/* Initialize default event subscriptions. By default, all the
3433 	 * options are off.
3434 	 */
3435 	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
3436 
3437 	/* Default Peer Address Parameters.  These defaults can
3438 	 * be modified via SCTP_PEER_ADDR_PARAMS
3439 	 */
3440 	sp->hbinterval  = sctp_hb_interval;
3441 	sp->pathmaxrxt  = sctp_max_retrans_path;
3442 	sp->pathmtu     = 0; // allow default discovery
3443 	sp->sackdelay   = sctp_sack_timeout;
3444 	sp->param_flags = SPP_HB_ENABLE |
3445 			  SPP_PMTUD_ENABLE |
3446 			  SPP_SACKDELAY_ENABLE;
3447 
3448 	/* If enabled no SCTP message fragmentation will be performed.
3449 	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
3450 	 */
3451 	sp->disable_fragments = 0;
3452 
3453 	/* Enable Nagle algorithm by default.  */
3454 	sp->nodelay           = 0;
3455 
3456 	/* Enable by default. */
3457 	sp->v4mapped          = 1;
3458 
3459 	/* Auto-close idle associations after the configured
3460 	 * number of seconds.  A value of 0 disables this
3461 	 * feature.  Configure through the SCTP_AUTOCLOSE socket option,
3462 	 * for UDP-style sockets only.
3463 	 */
3464 	sp->autoclose         = 0;
3465 
3466 	/* User specified fragmentation limit. */
3467 	sp->user_frag         = 0;
3468 
3469 	sp->adaptation_ind = 0;
3470 
3471 	sp->pf = sctp_get_pf_specific(sk->sk_family);
3472 
3473 	/* Control variables for partial data delivery. */
3474 	atomic_set(&sp->pd_mode, 0);
3475 	skb_queue_head_init(&sp->pd_lobby);
3476 	sp->frag_interleave = 0;
3477 
3478 	/* Create a per socket endpoint structure.  Even if we
3479 	 * change the data structure relationships, this may still
3480 	 * be useful for storing pre-connect address information.
3481 	 */
3482 	ep = sctp_endpoint_new(sk, GFP_KERNEL);
3483 	if (!ep)
3484 		return -ENOMEM;
3485 
3486 	sp->ep = ep;
3487 	sp->hmac = NULL;
3488 
3489 	SCTP_DBG_OBJCNT_INC(sock);
3490 	atomic_inc(&sctp_sockets_allocated);
3491 	return 0;
3492 }
3493 
3494 /* Cleanup any SCTP per socket resources.  */
3495 SCTP_STATIC int sctp_destroy_sock(struct sock *sk)
3496 {
3497 	struct sctp_endpoint *ep;
3498 
3499 	SCTP_DEBUG_PRINTK("sctp_destroy_sock(sk: %p)\n", sk);
3500 
3501 	/* Release our hold on the endpoint. */
3502 	ep = sctp_sk(sk)->ep;
3503 	sctp_endpoint_free(ep);
3504 	atomic_dec(&sctp_sockets_allocated);
3505 	return 0;
3506 }
3507 
3508 /* API 4.1.7 shutdown() - TCP Style Syntax
3509  *     int shutdown(int socket, int how);
3510  *
3511  *     sd      - the socket descriptor of the association to be closed.
3512  *     how     - Specifies the type of shutdown.  The  values  are
3513  *               as follows:
3514  *               SHUT_RD
3515  *                     Disables further receive operations. No SCTP
3516  *                     protocol action is taken.
3517  *               SHUT_WR
3518  *                     Disables further send operations, and initiates
3519  *                     the SCTP shutdown sequence.
3520  *               SHUT_RDWR
3521  *                     Disables further send  and  receive  operations
3522  *                     and initiates the SCTP shutdown sequence.
3523  */
3524 SCTP_STATIC void sctp_shutdown(struct sock *sk, int how)
3525 {
3526 	struct sctp_endpoint *ep;
3527 	struct sctp_association *asoc;
3528 
3529 	if (!sctp_style(sk, TCP))
3530 		return;
3531 
3532 	if (how & SEND_SHUTDOWN) {
3533 		ep = sctp_sk(sk)->ep;
3534 		if (!list_empty(&ep->asocs)) {
3535 			asoc = list_entry(ep->asocs.next,
3536 					  struct sctp_association, asocs);
3537 			sctp_primitive_SHUTDOWN(asoc, NULL);
3538 		}
3539 	}
3540 }
3541 
3542 /* 7.2.1 Association Status (SCTP_STATUS)
3543 
3544  * Applications can retrieve current status information about an
3545  * association, including association state, peer receiver window size,
3546  * number of unacked data chunks, and number of data chunks pending
3547  * receipt.  This information is read-only.
3548  */
3549 static int sctp_getsockopt_sctp_status(struct sock *sk, int len,
3550 				       char __user *optval,
3551 				       int __user *optlen)
3552 {
3553 	struct sctp_status status;
3554 	struct sctp_association *asoc = NULL;
3555 	struct sctp_transport *transport;
3556 	sctp_assoc_t associd;
3557 	int retval = 0;
3558 
3559 	if (len < sizeof(status)) {
3560 		retval = -EINVAL;
3561 		goto out;
3562 	}
3563 
3564 	len = sizeof(status);
3565 	if (copy_from_user(&status, optval, len)) {
3566 		retval = -EFAULT;
3567 		goto out;
3568 	}
3569 
3570 	associd = status.sstat_assoc_id;
3571 	asoc = sctp_id2assoc(sk, associd);
3572 	if (!asoc) {
3573 		retval = -EINVAL;
3574 		goto out;
3575 	}
3576 
3577 	transport = asoc->peer.primary_path;
3578 
3579 	status.sstat_assoc_id = sctp_assoc2id(asoc);
3580 	status.sstat_state = asoc->state;
3581 	status.sstat_rwnd =  asoc->peer.rwnd;
3582 	status.sstat_unackdata = asoc->unack_data;
3583 
3584 	status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
3585 	status.sstat_instrms = asoc->c.sinit_max_instreams;
3586 	status.sstat_outstrms = asoc->c.sinit_num_ostreams;
3587 	status.sstat_fragmentation_point = asoc->frag_point;
3588 	status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3589 	memcpy(&status.sstat_primary.spinfo_address, &transport->ipaddr,
3590 			transport->af_specific->sockaddr_len);
3591 	/* Map ipv4 address into v4-mapped-on-v6 address.  */
3592 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
3593 		(union sctp_addr *)&status.sstat_primary.spinfo_address);
3594 	status.sstat_primary.spinfo_state = transport->state;
3595 	status.sstat_primary.spinfo_cwnd = transport->cwnd;
3596 	status.sstat_primary.spinfo_srtt = transport->srtt;
3597 	status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
3598 	status.sstat_primary.spinfo_mtu = transport->pathmtu;
3599 
3600 	if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
3601 		status.sstat_primary.spinfo_state = SCTP_ACTIVE;
3602 
3603 	if (put_user(len, optlen)) {
3604 		retval = -EFAULT;
3605 		goto out;
3606 	}
3607 
3608 	SCTP_DEBUG_PRINTK("sctp_getsockopt_sctp_status(%d): %d %d %d\n",
3609 			  len, status.sstat_state, status.sstat_rwnd,
3610 			  status.sstat_assoc_id);
3611 
3612 	if (copy_to_user(optval, &status, len)) {
3613 		retval = -EFAULT;
3614 		goto out;
3615 	}
3616 
3617 out:
3618 	return (retval);
3619 }
3620 
3621 
3622 /* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
3623  *
3624  * Applications can retrieve information about a specific peer address
3625  * of an association, including its reachability state, congestion
3626  * window, and retransmission timer values.  This information is
3627  * read-only.
3628  */
3629 static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
3630 					  char __user *optval,
3631 					  int __user *optlen)
3632 {
3633 	struct sctp_paddrinfo pinfo;
3634 	struct sctp_transport *transport;
3635 	int retval = 0;
3636 
3637 	if (len < sizeof(pinfo)) {
3638 		retval = -EINVAL;
3639 		goto out;
3640 	}
3641 
3642 	len = sizeof(pinfo);
3643 	if (copy_from_user(&pinfo, optval, len)) {
3644 		retval = -EFAULT;
3645 		goto out;
3646 	}
3647 
3648 	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
3649 					   pinfo.spinfo_assoc_id);
3650 	if (!transport)
3651 		return -EINVAL;
3652 
3653 	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3654 	pinfo.spinfo_state = transport->state;
3655 	pinfo.spinfo_cwnd = transport->cwnd;
3656 	pinfo.spinfo_srtt = transport->srtt;
3657 	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
3658 	pinfo.spinfo_mtu = transport->pathmtu;
3659 
3660 	if (pinfo.spinfo_state == SCTP_UNKNOWN)
3661 		pinfo.spinfo_state = SCTP_ACTIVE;
3662 
3663 	if (put_user(len, optlen)) {
3664 		retval = -EFAULT;
3665 		goto out;
3666 	}
3667 
3668 	if (copy_to_user(optval, &pinfo, len)) {
3669 		retval = -EFAULT;
3670 		goto out;
3671 	}
3672 
3673 out:
3674 	return (retval);
3675 }
3676 
3677 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
3678  *
3679  * This option is a on/off flag.  If enabled no SCTP message
3680  * fragmentation will be performed.  Instead if a message being sent
3681  * exceeds the current PMTU size, the message will NOT be sent and
3682  * instead a error will be indicated to the user.
3683  */
3684 static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
3685 					char __user *optval, int __user *optlen)
3686 {
3687 	int val;
3688 
3689 	if (len < sizeof(int))
3690 		return -EINVAL;
3691 
3692 	len = sizeof(int);
3693 	val = (sctp_sk(sk)->disable_fragments == 1);
3694 	if (put_user(len, optlen))
3695 		return -EFAULT;
3696 	if (copy_to_user(optval, &val, len))
3697 		return -EFAULT;
3698 	return 0;
3699 }
3700 
3701 /* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
3702  *
3703  * This socket option is used to specify various notifications and
3704  * ancillary data the user wishes to receive.
3705  */
3706 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
3707 				  int __user *optlen)
3708 {
3709 	if (len < sizeof(struct sctp_event_subscribe))
3710 		return -EINVAL;
3711 	len = sizeof(struct sctp_event_subscribe);
3712 	if (put_user(len, optlen))
3713 		return -EFAULT;
3714 	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
3715 		return -EFAULT;
3716 	return 0;
3717 }
3718 
3719 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
3720  *
3721  * This socket option is applicable to the UDP-style socket only.  When
3722  * set it will cause associations that are idle for more than the
3723  * specified number of seconds to automatically close.  An association
3724  * being idle is defined an association that has NOT sent or received
3725  * user data.  The special value of '0' indicates that no automatic
3726  * close of any associations should be performed.  The option expects an
3727  * integer defining the number of seconds of idle time before an
3728  * association is closed.
3729  */
3730 static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
3731 {
3732 	/* Applicable to UDP-style socket only */
3733 	if (sctp_style(sk, TCP))
3734 		return -EOPNOTSUPP;
3735 	if (len < sizeof(int))
3736 		return -EINVAL;
3737 	len = sizeof(int);
3738 	if (put_user(len, optlen))
3739 		return -EFAULT;
3740 	if (copy_to_user(optval, &sctp_sk(sk)->autoclose, sizeof(int)))
3741 		return -EFAULT;
3742 	return 0;
3743 }
3744 
3745 /* Helper routine to branch off an association to a new socket.  */
3746 SCTP_STATIC int sctp_do_peeloff(struct sctp_association *asoc,
3747 				struct socket **sockp)
3748 {
3749 	struct sock *sk = asoc->base.sk;
3750 	struct socket *sock;
3751 	struct inet_sock *inetsk;
3752 	struct sctp_af *af;
3753 	int err = 0;
3754 
3755 	/* An association cannot be branched off from an already peeled-off
3756 	 * socket, nor is this supported for tcp style sockets.
3757 	 */
3758 	if (!sctp_style(sk, UDP))
3759 		return -EINVAL;
3760 
3761 	/* Create a new socket.  */
3762 	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
3763 	if (err < 0)
3764 		return err;
3765 
3766 	/* Populate the fields of the newsk from the oldsk and migrate the
3767 	 * asoc to the newsk.
3768 	 */
3769 	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
3770 
3771 	/* Make peeled-off sockets more like 1-1 accepted sockets.
3772 	 * Set the daddr and initialize id to something more random
3773 	 */
3774 	af = sctp_get_af_specific(asoc->peer.primary_addr.sa.sa_family);
3775 	af->to_sk_daddr(&asoc->peer.primary_addr, sk);
3776 	inetsk = inet_sk(sock->sk);
3777 	inetsk->id = asoc->next_tsn ^ jiffies;
3778 
3779 	*sockp = sock;
3780 
3781 	return err;
3782 }
3783 
3784 static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
3785 {
3786 	sctp_peeloff_arg_t peeloff;
3787 	struct socket *newsock;
3788 	int retval = 0;
3789 	struct sctp_association *asoc;
3790 
3791 	if (len < sizeof(sctp_peeloff_arg_t))
3792 		return -EINVAL;
3793 	len = sizeof(sctp_peeloff_arg_t);
3794 	if (copy_from_user(&peeloff, optval, len))
3795 		return -EFAULT;
3796 
3797 	asoc = sctp_id2assoc(sk, peeloff.associd);
3798 	if (!asoc) {
3799 		retval = -EINVAL;
3800 		goto out;
3801 	}
3802 
3803 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p\n", __FUNCTION__, sk, asoc);
3804 
3805 	retval = sctp_do_peeloff(asoc, &newsock);
3806 	if (retval < 0)
3807 		goto out;
3808 
3809 	/* Map the socket to an unused fd that can be returned to the user.  */
3810 	retval = sock_map_fd(newsock);
3811 	if (retval < 0) {
3812 		sock_release(newsock);
3813 		goto out;
3814 	}
3815 
3816 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p newsk: %p sd: %d\n",
3817 			  __FUNCTION__, sk, asoc, newsock->sk, retval);
3818 
3819 	/* Return the fd mapped to the new socket.  */
3820 	peeloff.sd = retval;
3821 	if (put_user(len, optlen))
3822 		return -EFAULT;
3823 	if (copy_to_user(optval, &peeloff, len))
3824 		retval = -EFAULT;
3825 
3826 out:
3827 	return retval;
3828 }
3829 
3830 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
3831  *
3832  * Applications can enable or disable heartbeats for any peer address of
3833  * an association, modify an address's heartbeat interval, force a
3834  * heartbeat to be sent immediately, and adjust the address's maximum
3835  * number of retransmissions sent before an address is considered
3836  * unreachable.  The following structure is used to access and modify an
3837  * address's parameters:
3838  *
3839  *  struct sctp_paddrparams {
3840  *     sctp_assoc_t            spp_assoc_id;
3841  *     struct sockaddr_storage spp_address;
3842  *     uint32_t                spp_hbinterval;
3843  *     uint16_t                spp_pathmaxrxt;
3844  *     uint32_t                spp_pathmtu;
3845  *     uint32_t                spp_sackdelay;
3846  *     uint32_t                spp_flags;
3847  * };
3848  *
3849  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
3850  *                     application, and identifies the association for
3851  *                     this query.
3852  *   spp_address     - This specifies which address is of interest.
3853  *   spp_hbinterval  - This contains the value of the heartbeat interval,
3854  *                     in milliseconds.  If a  value of zero
3855  *                     is present in this field then no changes are to
3856  *                     be made to this parameter.
3857  *   spp_pathmaxrxt  - This contains the maximum number of
3858  *                     retransmissions before this address shall be
3859  *                     considered unreachable. If a  value of zero
3860  *                     is present in this field then no changes are to
3861  *                     be made to this parameter.
3862  *   spp_pathmtu     - When Path MTU discovery is disabled the value
3863  *                     specified here will be the "fixed" path mtu.
3864  *                     Note that if the spp_address field is empty
3865  *                     then all associations on this address will
3866  *                     have this fixed path mtu set upon them.
3867  *
3868  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
3869  *                     the number of milliseconds that sacks will be delayed
3870  *                     for. This value will apply to all addresses of an
3871  *                     association if the spp_address field is empty. Note
3872  *                     also, that if delayed sack is enabled and this
3873  *                     value is set to 0, no change is made to the last
3874  *                     recorded delayed sack timer value.
3875  *
3876  *   spp_flags       - These flags are used to control various features
3877  *                     on an association. The flag field may contain
3878  *                     zero or more of the following options.
3879  *
3880  *                     SPP_HB_ENABLE  - Enable heartbeats on the
3881  *                     specified address. Note that if the address
3882  *                     field is empty all addresses for the association
3883  *                     have heartbeats enabled upon them.
3884  *
3885  *                     SPP_HB_DISABLE - Disable heartbeats on the
3886  *                     speicifed address. Note that if the address
3887  *                     field is empty all addresses for the association
3888  *                     will have their heartbeats disabled. Note also
3889  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
3890  *                     mutually exclusive, only one of these two should
3891  *                     be specified. Enabling both fields will have
3892  *                     undetermined results.
3893  *
3894  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
3895  *                     to be made immediately.
3896  *
3897  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
3898  *                     discovery upon the specified address. Note that
3899  *                     if the address feild is empty then all addresses
3900  *                     on the association are effected.
3901  *
3902  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
3903  *                     discovery upon the specified address. Note that
3904  *                     if the address feild is empty then all addresses
3905  *                     on the association are effected. Not also that
3906  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
3907  *                     exclusive. Enabling both will have undetermined
3908  *                     results.
3909  *
3910  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
3911  *                     on delayed sack. The time specified in spp_sackdelay
3912  *                     is used to specify the sack delay for this address. Note
3913  *                     that if spp_address is empty then all addresses will
3914  *                     enable delayed sack and take on the sack delay
3915  *                     value specified in spp_sackdelay.
3916  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
3917  *                     off delayed sack. If the spp_address field is blank then
3918  *                     delayed sack is disabled for the entire association. Note
3919  *                     also that this field is mutually exclusive to
3920  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
3921  *                     results.
3922  */
3923 static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
3924 					    char __user *optval, int __user *optlen)
3925 {
3926 	struct sctp_paddrparams  params;
3927 	struct sctp_transport   *trans = NULL;
3928 	struct sctp_association *asoc = NULL;
3929 	struct sctp_sock        *sp = sctp_sk(sk);
3930 
3931 	if (len < sizeof(struct sctp_paddrparams))
3932 		return -EINVAL;
3933 	len = sizeof(struct sctp_paddrparams);
3934 	if (copy_from_user(&params, optval, len))
3935 		return -EFAULT;
3936 
3937 	/* If an address other than INADDR_ANY is specified, and
3938 	 * no transport is found, then the request is invalid.
3939 	 */
3940 	if (!sctp_is_any(( union sctp_addr *)&params.spp_address)) {
3941 		trans = sctp_addr_id2transport(sk, &params.spp_address,
3942 					       params.spp_assoc_id);
3943 		if (!trans) {
3944 			SCTP_DEBUG_PRINTK("Failed no transport\n");
3945 			return -EINVAL;
3946 		}
3947 	}
3948 
3949 	/* Get association, if assoc_id != 0 and the socket is a one
3950 	 * to many style socket, and an association was not found, then
3951 	 * the id was invalid.
3952 	 */
3953 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
3954 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
3955 		SCTP_DEBUG_PRINTK("Failed no association\n");
3956 		return -EINVAL;
3957 	}
3958 
3959 	if (trans) {
3960 		/* Fetch transport values. */
3961 		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
3962 		params.spp_pathmtu    = trans->pathmtu;
3963 		params.spp_pathmaxrxt = trans->pathmaxrxt;
3964 		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
3965 
3966 		/*draft-11 doesn't say what to return in spp_flags*/
3967 		params.spp_flags      = trans->param_flags;
3968 	} else if (asoc) {
3969 		/* Fetch association values. */
3970 		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
3971 		params.spp_pathmtu    = asoc->pathmtu;
3972 		params.spp_pathmaxrxt = asoc->pathmaxrxt;
3973 		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
3974 
3975 		/*draft-11 doesn't say what to return in spp_flags*/
3976 		params.spp_flags      = asoc->param_flags;
3977 	} else {
3978 		/* Fetch socket values. */
3979 		params.spp_hbinterval = sp->hbinterval;
3980 		params.spp_pathmtu    = sp->pathmtu;
3981 		params.spp_sackdelay  = sp->sackdelay;
3982 		params.spp_pathmaxrxt = sp->pathmaxrxt;
3983 
3984 		/*draft-11 doesn't say what to return in spp_flags*/
3985 		params.spp_flags      = sp->param_flags;
3986 	}
3987 
3988 	if (copy_to_user(optval, &params, len))
3989 		return -EFAULT;
3990 
3991 	if (put_user(len, optlen))
3992 		return -EFAULT;
3993 
3994 	return 0;
3995 }
3996 
3997 /* 7.1.23. Delayed Ack Timer (SCTP_DELAYED_ACK_TIME)
3998  *
3999  *   This options will get or set the delayed ack timer.  The time is set
4000  *   in milliseconds.  If the assoc_id is 0, then this sets or gets the
4001  *   endpoints default delayed ack timer value.  If the assoc_id field is
4002  *   non-zero, then the set or get effects the specified association.
4003  *
4004  *   struct sctp_assoc_value {
4005  *       sctp_assoc_t            assoc_id;
4006  *       uint32_t                assoc_value;
4007  *   };
4008  *
4009  *     assoc_id    - This parameter, indicates which association the
4010  *                   user is preforming an action upon. Note that if
4011  *                   this field's value is zero then the endpoints
4012  *                   default value is changed (effecting future
4013  *                   associations only).
4014  *
4015  *     assoc_value - This parameter contains the number of milliseconds
4016  *                   that the user is requesting the delayed ACK timer
4017  *                   be set to. Note that this value is defined in
4018  *                   the standard to be between 200 and 500 milliseconds.
4019  *
4020  *                   Note: a value of zero will leave the value alone,
4021  *                   but disable SACK delay. A non-zero value will also
4022  *                   enable SACK delay.
4023  */
4024 static int sctp_getsockopt_delayed_ack_time(struct sock *sk, int len,
4025 					    char __user *optval,
4026 					    int __user *optlen)
4027 {
4028 	struct sctp_assoc_value  params;
4029 	struct sctp_association *asoc = NULL;
4030 	struct sctp_sock        *sp = sctp_sk(sk);
4031 
4032 	if (len < sizeof(struct sctp_assoc_value))
4033 		return - EINVAL;
4034 
4035 	len = sizeof(struct sctp_assoc_value);
4036 
4037 	if (copy_from_user(&params, optval, len))
4038 		return -EFAULT;
4039 
4040 	/* Get association, if assoc_id != 0 and the socket is a one
4041 	 * to many style socket, and an association was not found, then
4042 	 * the id was invalid.
4043 	 */
4044 	asoc = sctp_id2assoc(sk, params.assoc_id);
4045 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
4046 		return -EINVAL;
4047 
4048 	if (asoc) {
4049 		/* Fetch association values. */
4050 		if (asoc->param_flags & SPP_SACKDELAY_ENABLE)
4051 			params.assoc_value = jiffies_to_msecs(
4052 				asoc->sackdelay);
4053 		else
4054 			params.assoc_value = 0;
4055 	} else {
4056 		/* Fetch socket values. */
4057 		if (sp->param_flags & SPP_SACKDELAY_ENABLE)
4058 			params.assoc_value  = sp->sackdelay;
4059 		else
4060 			params.assoc_value  = 0;
4061 	}
4062 
4063 	if (copy_to_user(optval, &params, len))
4064 		return -EFAULT;
4065 
4066 	if (put_user(len, optlen))
4067 		return -EFAULT;
4068 
4069 	return 0;
4070 }
4071 
4072 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
4073  *
4074  * Applications can specify protocol parameters for the default association
4075  * initialization.  The option name argument to setsockopt() and getsockopt()
4076  * is SCTP_INITMSG.
4077  *
4078  * Setting initialization parameters is effective only on an unconnected
4079  * socket (for UDP-style sockets only future associations are effected
4080  * by the change).  With TCP-style sockets, this option is inherited by
4081  * sockets derived from a listener socket.
4082  */
4083 static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
4084 {
4085 	if (len < sizeof(struct sctp_initmsg))
4086 		return -EINVAL;
4087 	len = sizeof(struct sctp_initmsg);
4088 	if (put_user(len, optlen))
4089 		return -EFAULT;
4090 	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
4091 		return -EFAULT;
4092 	return 0;
4093 }
4094 
4095 static int sctp_getsockopt_peer_addrs_num_old(struct sock *sk, int len,
4096 					      char __user *optval,
4097 					      int __user *optlen)
4098 {
4099 	sctp_assoc_t id;
4100 	struct sctp_association *asoc;
4101 	struct list_head *pos;
4102 	int cnt = 0;
4103 
4104 	if (len < sizeof(sctp_assoc_t))
4105 		return -EINVAL;
4106 
4107 	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
4108 		return -EFAULT;
4109 
4110 	/* For UDP-style sockets, id specifies the association to query.  */
4111 	asoc = sctp_id2assoc(sk, id);
4112 	if (!asoc)
4113 		return -EINVAL;
4114 
4115 	list_for_each(pos, &asoc->peer.transport_addr_list) {
4116 		cnt ++;
4117 	}
4118 
4119 	return cnt;
4120 }
4121 
4122 /*
4123  * Old API for getting list of peer addresses. Does not work for 32-bit
4124  * programs running on a 64-bit kernel
4125  */
4126 static int sctp_getsockopt_peer_addrs_old(struct sock *sk, int len,
4127 					  char __user *optval,
4128 					  int __user *optlen)
4129 {
4130 	struct sctp_association *asoc;
4131 	struct list_head *pos;
4132 	int cnt = 0;
4133 	struct sctp_getaddrs_old getaddrs;
4134 	struct sctp_transport *from;
4135 	void __user *to;
4136 	union sctp_addr temp;
4137 	struct sctp_sock *sp = sctp_sk(sk);
4138 	int addrlen;
4139 
4140 	if (len < sizeof(struct sctp_getaddrs_old))
4141 		return -EINVAL;
4142 
4143 	len = sizeof(struct sctp_getaddrs_old);
4144 
4145 	if (copy_from_user(&getaddrs, optval, len))
4146 		return -EFAULT;
4147 
4148 	if (getaddrs.addr_num <= 0) return -EINVAL;
4149 
4150 	/* For UDP-style sockets, id specifies the association to query.  */
4151 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4152 	if (!asoc)
4153 		return -EINVAL;
4154 
4155 	to = (void __user *)getaddrs.addrs;
4156 	list_for_each(pos, &asoc->peer.transport_addr_list) {
4157 		from = list_entry(pos, struct sctp_transport, transports);
4158 		memcpy(&temp, &from->ipaddr, sizeof(temp));
4159 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4160 		addrlen = sctp_get_af_specific(sk->sk_family)->sockaddr_len;
4161 		if (copy_to_user(to, &temp, addrlen))
4162 			return -EFAULT;
4163 		to += addrlen ;
4164 		cnt ++;
4165 		if (cnt >= getaddrs.addr_num) break;
4166 	}
4167 	getaddrs.addr_num = cnt;
4168 	if (put_user(len, optlen))
4169 		return -EFAULT;
4170 	if (copy_to_user(optval, &getaddrs, len))
4171 		return -EFAULT;
4172 
4173 	return 0;
4174 }
4175 
4176 static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
4177 				      char __user *optval, int __user *optlen)
4178 {
4179 	struct sctp_association *asoc;
4180 	struct list_head *pos;
4181 	int cnt = 0;
4182 	struct sctp_getaddrs getaddrs;
4183 	struct sctp_transport *from;
4184 	void __user *to;
4185 	union sctp_addr temp;
4186 	struct sctp_sock *sp = sctp_sk(sk);
4187 	int addrlen;
4188 	size_t space_left;
4189 	int bytes_copied;
4190 
4191 	if (len < sizeof(struct sctp_getaddrs))
4192 		return -EINVAL;
4193 
4194 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4195 		return -EFAULT;
4196 
4197 	/* For UDP-style sockets, id specifies the association to query.  */
4198 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4199 	if (!asoc)
4200 		return -EINVAL;
4201 
4202 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4203 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4204 
4205 	list_for_each(pos, &asoc->peer.transport_addr_list) {
4206 		from = list_entry(pos, struct sctp_transport, transports);
4207 		memcpy(&temp, &from->ipaddr, sizeof(temp));
4208 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4209 		addrlen = sctp_get_af_specific(sk->sk_family)->sockaddr_len;
4210 		if (space_left < addrlen)
4211 			return -ENOMEM;
4212 		if (copy_to_user(to, &temp, addrlen))
4213 			return -EFAULT;
4214 		to += addrlen;
4215 		cnt++;
4216 		space_left -= addrlen;
4217 	}
4218 
4219 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
4220 		return -EFAULT;
4221 	bytes_copied = ((char __user *)to) - optval;
4222 	if (put_user(bytes_copied, optlen))
4223 		return -EFAULT;
4224 
4225 	return 0;
4226 }
4227 
4228 static int sctp_getsockopt_local_addrs_num_old(struct sock *sk, int len,
4229 					       char __user *optval,
4230 					       int __user *optlen)
4231 {
4232 	sctp_assoc_t id;
4233 	struct sctp_bind_addr *bp;
4234 	struct sctp_association *asoc;
4235 	struct sctp_sockaddr_entry *addr;
4236 	int cnt = 0;
4237 
4238 	if (len < sizeof(sctp_assoc_t))
4239 		return -EINVAL;
4240 
4241 	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
4242 		return -EFAULT;
4243 
4244 	/*
4245 	 *  For UDP-style sockets, id specifies the association to query.
4246 	 *  If the id field is set to the value '0' then the locally bound
4247 	 *  addresses are returned without regard to any particular
4248 	 *  association.
4249 	 */
4250 	if (0 == id) {
4251 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4252 	} else {
4253 		asoc = sctp_id2assoc(sk, id);
4254 		if (!asoc)
4255 			return -EINVAL;
4256 		bp = &asoc->base.bind_addr;
4257 	}
4258 
4259 	/* If the endpoint is bound to 0.0.0.0 or ::0, count the valid
4260 	 * addresses from the global local address list.
4261 	 */
4262 	if (sctp_list_single_entry(&bp->address_list)) {
4263 		addr = list_entry(bp->address_list.next,
4264 				  struct sctp_sockaddr_entry, list);
4265 		if (sctp_is_any(&addr->a)) {
4266 			rcu_read_lock();
4267 			list_for_each_entry_rcu(addr,
4268 						&sctp_local_addr_list, list) {
4269 				if (!addr->valid)
4270 					continue;
4271 
4272 				if ((PF_INET == sk->sk_family) &&
4273 				    (AF_INET6 == addr->a.sa.sa_family))
4274 					continue;
4275 
4276 				cnt++;
4277 			}
4278 			rcu_read_unlock();
4279 		} else {
4280 			cnt = 1;
4281 		}
4282 		goto done;
4283 	}
4284 
4285 	/* Protection on the bound address list is not needed,
4286 	 * since in the socket option context we hold the socket lock,
4287 	 * so there is no way that the bound address list can change.
4288 	 */
4289 	list_for_each_entry(addr, &bp->address_list, list) {
4290 		cnt ++;
4291 	}
4292 done:
4293 	return cnt;
4294 }
4295 
4296 /* Helper function that copies local addresses to user and returns the number
4297  * of addresses copied.
4298  */
4299 static int sctp_copy_laddrs_old(struct sock *sk, __u16 port,
4300 					int max_addrs, void *to,
4301 					int *bytes_copied)
4302 {
4303 	struct sctp_sockaddr_entry *addr;
4304 	union sctp_addr temp;
4305 	int cnt = 0;
4306 	int addrlen;
4307 
4308 	rcu_read_lock();
4309 	list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
4310 		if (!addr->valid)
4311 			continue;
4312 
4313 		if ((PF_INET == sk->sk_family) &&
4314 		    (AF_INET6 == addr->a.sa.sa_family))
4315 			continue;
4316 		memcpy(&temp, &addr->a, sizeof(temp));
4317 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4318 								&temp);
4319 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4320 		memcpy(to, &temp, addrlen);
4321 
4322 		to += addrlen;
4323 		*bytes_copied += addrlen;
4324 		cnt ++;
4325 		if (cnt >= max_addrs) break;
4326 	}
4327 	rcu_read_unlock();
4328 
4329 	return cnt;
4330 }
4331 
4332 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
4333 			    size_t space_left, int *bytes_copied)
4334 {
4335 	struct sctp_sockaddr_entry *addr;
4336 	union sctp_addr temp;
4337 	int cnt = 0;
4338 	int addrlen;
4339 
4340 	rcu_read_lock();
4341 	list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
4342 		if (!addr->valid)
4343 			continue;
4344 
4345 		if ((PF_INET == sk->sk_family) &&
4346 		    (AF_INET6 == addr->a.sa.sa_family))
4347 			continue;
4348 		memcpy(&temp, &addr->a, sizeof(temp));
4349 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4350 								&temp);
4351 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4352 		if (space_left < addrlen) {
4353 			cnt =  -ENOMEM;
4354 			break;
4355 		}
4356 		memcpy(to, &temp, addrlen);
4357 
4358 		to += addrlen;
4359 		cnt ++;
4360 		space_left -= addrlen;
4361 		*bytes_copied += addrlen;
4362 	}
4363 	rcu_read_unlock();
4364 
4365 	return cnt;
4366 }
4367 
4368 /* Old API for getting list of local addresses. Does not work for 32-bit
4369  * programs running on a 64-bit kernel
4370  */
4371 static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
4372 					   char __user *optval, int __user *optlen)
4373 {
4374 	struct sctp_bind_addr *bp;
4375 	struct sctp_association *asoc;
4376 	int cnt = 0;
4377 	struct sctp_getaddrs_old getaddrs;
4378 	struct sctp_sockaddr_entry *addr;
4379 	void __user *to;
4380 	union sctp_addr temp;
4381 	struct sctp_sock *sp = sctp_sk(sk);
4382 	int addrlen;
4383 	int err = 0;
4384 	void *addrs;
4385 	void *buf;
4386 	int bytes_copied = 0;
4387 
4388 	if (len < sizeof(struct sctp_getaddrs_old))
4389 		return -EINVAL;
4390 
4391 	len = sizeof(struct sctp_getaddrs_old);
4392 	if (copy_from_user(&getaddrs, optval, len))
4393 		return -EFAULT;
4394 
4395 	if (getaddrs.addr_num <= 0) return -EINVAL;
4396 	/*
4397 	 *  For UDP-style sockets, id specifies the association to query.
4398 	 *  If the id field is set to the value '0' then the locally bound
4399 	 *  addresses are returned without regard to any particular
4400 	 *  association.
4401 	 */
4402 	if (0 == getaddrs.assoc_id) {
4403 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4404 	} else {
4405 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4406 		if (!asoc)
4407 			return -EINVAL;
4408 		bp = &asoc->base.bind_addr;
4409 	}
4410 
4411 	to = getaddrs.addrs;
4412 
4413 	/* Allocate space for a local instance of packed array to hold all
4414 	 * the data.  We store addresses here first and then put write them
4415 	 * to the user in one shot.
4416 	 */
4417 	addrs = kmalloc(sizeof(union sctp_addr) * getaddrs.addr_num,
4418 			GFP_KERNEL);
4419 	if (!addrs)
4420 		return -ENOMEM;
4421 
4422 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4423 	 * addresses from the global local address list.
4424 	 */
4425 	if (sctp_list_single_entry(&bp->address_list)) {
4426 		addr = list_entry(bp->address_list.next,
4427 				  struct sctp_sockaddr_entry, list);
4428 		if (sctp_is_any(&addr->a)) {
4429 			cnt = sctp_copy_laddrs_old(sk, bp->port,
4430 						   getaddrs.addr_num,
4431 						   addrs, &bytes_copied);
4432 			goto copy_getaddrs;
4433 		}
4434 	}
4435 
4436 	buf = addrs;
4437 	/* Protection on the bound address list is not needed since
4438 	 * in the socket option context we hold a socket lock and
4439 	 * thus the bound address list can't change.
4440 	 */
4441 	list_for_each_entry(addr, &bp->address_list, list) {
4442 		memcpy(&temp, &addr->a, sizeof(temp));
4443 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4444 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4445 		memcpy(buf, &temp, addrlen);
4446 		buf += addrlen;
4447 		bytes_copied += addrlen;
4448 		cnt ++;
4449 		if (cnt >= getaddrs.addr_num) break;
4450 	}
4451 
4452 copy_getaddrs:
4453 	/* copy the entire address list into the user provided space */
4454 	if (copy_to_user(to, addrs, bytes_copied)) {
4455 		err = -EFAULT;
4456 		goto error;
4457 	}
4458 
4459 	/* copy the leading structure back to user */
4460 	getaddrs.addr_num = cnt;
4461 	if (copy_to_user(optval, &getaddrs, len))
4462 		err = -EFAULT;
4463 
4464 error:
4465 	kfree(addrs);
4466 	return err;
4467 }
4468 
4469 static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
4470 				       char __user *optval, int __user *optlen)
4471 {
4472 	struct sctp_bind_addr *bp;
4473 	struct sctp_association *asoc;
4474 	int cnt = 0;
4475 	struct sctp_getaddrs getaddrs;
4476 	struct sctp_sockaddr_entry *addr;
4477 	void __user *to;
4478 	union sctp_addr temp;
4479 	struct sctp_sock *sp = sctp_sk(sk);
4480 	int addrlen;
4481 	int err = 0;
4482 	size_t space_left;
4483 	int bytes_copied = 0;
4484 	void *addrs;
4485 	void *buf;
4486 
4487 	if (len < sizeof(struct sctp_getaddrs))
4488 		return -EINVAL;
4489 
4490 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4491 		return -EFAULT;
4492 
4493 	/*
4494 	 *  For UDP-style sockets, id specifies the association to query.
4495 	 *  If the id field is set to the value '0' then the locally bound
4496 	 *  addresses are returned without regard to any particular
4497 	 *  association.
4498 	 */
4499 	if (0 == getaddrs.assoc_id) {
4500 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4501 	} else {
4502 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4503 		if (!asoc)
4504 			return -EINVAL;
4505 		bp = &asoc->base.bind_addr;
4506 	}
4507 
4508 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4509 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4510 
4511 	addrs = kmalloc(space_left, GFP_KERNEL);
4512 	if (!addrs)
4513 		return -ENOMEM;
4514 
4515 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4516 	 * addresses from the global local address list.
4517 	 */
4518 	if (sctp_list_single_entry(&bp->address_list)) {
4519 		addr = list_entry(bp->address_list.next,
4520 				  struct sctp_sockaddr_entry, list);
4521 		if (sctp_is_any(&addr->a)) {
4522 			cnt = sctp_copy_laddrs(sk, bp->port, addrs,
4523 						space_left, &bytes_copied);
4524 			if (cnt < 0) {
4525 				err = cnt;
4526 				goto out;
4527 			}
4528 			goto copy_getaddrs;
4529 		}
4530 	}
4531 
4532 	buf = addrs;
4533 	/* Protection on the bound address list is not needed since
4534 	 * in the socket option context we hold a socket lock and
4535 	 * thus the bound address list can't change.
4536 	 */
4537 	list_for_each_entry(addr, &bp->address_list, list) {
4538 		memcpy(&temp, &addr->a, sizeof(temp));
4539 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4540 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4541 		if (space_left < addrlen) {
4542 			err =  -ENOMEM; /*fixme: right error?*/
4543 			goto out;
4544 		}
4545 		memcpy(buf, &temp, addrlen);
4546 		buf += addrlen;
4547 		bytes_copied += addrlen;
4548 		cnt ++;
4549 		space_left -= addrlen;
4550 	}
4551 
4552 copy_getaddrs:
4553 	if (copy_to_user(to, addrs, bytes_copied)) {
4554 		err = -EFAULT;
4555 		goto out;
4556 	}
4557 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num)) {
4558 		err = -EFAULT;
4559 		goto out;
4560 	}
4561 	if (put_user(bytes_copied, optlen))
4562 		err = -EFAULT;
4563 out:
4564 	kfree(addrs);
4565 	return err;
4566 }
4567 
4568 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
4569  *
4570  * Requests that the local SCTP stack use the enclosed peer address as
4571  * the association primary.  The enclosed address must be one of the
4572  * association peer's addresses.
4573  */
4574 static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
4575 					char __user *optval, int __user *optlen)
4576 {
4577 	struct sctp_prim prim;
4578 	struct sctp_association *asoc;
4579 	struct sctp_sock *sp = sctp_sk(sk);
4580 
4581 	if (len < sizeof(struct sctp_prim))
4582 		return -EINVAL;
4583 
4584 	len = sizeof(struct sctp_prim);
4585 
4586 	if (copy_from_user(&prim, optval, len))
4587 		return -EFAULT;
4588 
4589 	asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
4590 	if (!asoc)
4591 		return -EINVAL;
4592 
4593 	if (!asoc->peer.primary_path)
4594 		return -ENOTCONN;
4595 
4596 	memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
4597 		asoc->peer.primary_path->af_specific->sockaddr_len);
4598 
4599 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp,
4600 			(union sctp_addr *)&prim.ssp_addr);
4601 
4602 	if (put_user(len, optlen))
4603 		return -EFAULT;
4604 	if (copy_to_user(optval, &prim, len))
4605 		return -EFAULT;
4606 
4607 	return 0;
4608 }
4609 
4610 /*
4611  * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
4612  *
4613  * Requests that the local endpoint set the specified Adaptation Layer
4614  * Indication parameter for all future INIT and INIT-ACK exchanges.
4615  */
4616 static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
4617 				  char __user *optval, int __user *optlen)
4618 {
4619 	struct sctp_setadaptation adaptation;
4620 
4621 	if (len < sizeof(struct sctp_setadaptation))
4622 		return -EINVAL;
4623 
4624 	len = sizeof(struct sctp_setadaptation);
4625 
4626 	adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
4627 
4628 	if (put_user(len, optlen))
4629 		return -EFAULT;
4630 	if (copy_to_user(optval, &adaptation, len))
4631 		return -EFAULT;
4632 
4633 	return 0;
4634 }
4635 
4636 /*
4637  *
4638  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
4639  *
4640  *   Applications that wish to use the sendto() system call may wish to
4641  *   specify a default set of parameters that would normally be supplied
4642  *   through the inclusion of ancillary data.  This socket option allows
4643  *   such an application to set the default sctp_sndrcvinfo structure.
4644 
4645 
4646  *   The application that wishes to use this socket option simply passes
4647  *   in to this call the sctp_sndrcvinfo structure defined in Section
4648  *   5.2.2) The input parameters accepted by this call include
4649  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
4650  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
4651  *   to this call if the caller is using the UDP model.
4652  *
4653  *   For getsockopt, it get the default sctp_sndrcvinfo structure.
4654  */
4655 static int sctp_getsockopt_default_send_param(struct sock *sk,
4656 					int len, char __user *optval,
4657 					int __user *optlen)
4658 {
4659 	struct sctp_sndrcvinfo info;
4660 	struct sctp_association *asoc;
4661 	struct sctp_sock *sp = sctp_sk(sk);
4662 
4663 	if (len < sizeof(struct sctp_sndrcvinfo))
4664 		return -EINVAL;
4665 
4666 	len = sizeof(struct sctp_sndrcvinfo);
4667 
4668 	if (copy_from_user(&info, optval, len))
4669 		return -EFAULT;
4670 
4671 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
4672 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
4673 		return -EINVAL;
4674 
4675 	if (asoc) {
4676 		info.sinfo_stream = asoc->default_stream;
4677 		info.sinfo_flags = asoc->default_flags;
4678 		info.sinfo_ppid = asoc->default_ppid;
4679 		info.sinfo_context = asoc->default_context;
4680 		info.sinfo_timetolive = asoc->default_timetolive;
4681 	} else {
4682 		info.sinfo_stream = sp->default_stream;
4683 		info.sinfo_flags = sp->default_flags;
4684 		info.sinfo_ppid = sp->default_ppid;
4685 		info.sinfo_context = sp->default_context;
4686 		info.sinfo_timetolive = sp->default_timetolive;
4687 	}
4688 
4689 	if (put_user(len, optlen))
4690 		return -EFAULT;
4691 	if (copy_to_user(optval, &info, len))
4692 		return -EFAULT;
4693 
4694 	return 0;
4695 }
4696 
4697 /*
4698  *
4699  * 7.1.5 SCTP_NODELAY
4700  *
4701  * Turn on/off any Nagle-like algorithm.  This means that packets are
4702  * generally sent as soon as possible and no unnecessary delays are
4703  * introduced, at the cost of more packets in the network.  Expects an
4704  * integer boolean flag.
4705  */
4706 
4707 static int sctp_getsockopt_nodelay(struct sock *sk, int len,
4708 				   char __user *optval, int __user *optlen)
4709 {
4710 	int val;
4711 
4712 	if (len < sizeof(int))
4713 		return -EINVAL;
4714 
4715 	len = sizeof(int);
4716 	val = (sctp_sk(sk)->nodelay == 1);
4717 	if (put_user(len, optlen))
4718 		return -EFAULT;
4719 	if (copy_to_user(optval, &val, len))
4720 		return -EFAULT;
4721 	return 0;
4722 }
4723 
4724 /*
4725  *
4726  * 7.1.1 SCTP_RTOINFO
4727  *
4728  * The protocol parameters used to initialize and bound retransmission
4729  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
4730  * and modify these parameters.
4731  * All parameters are time values, in milliseconds.  A value of 0, when
4732  * modifying the parameters, indicates that the current value should not
4733  * be changed.
4734  *
4735  */
4736 static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
4737 				char __user *optval,
4738 				int __user *optlen) {
4739 	struct sctp_rtoinfo rtoinfo;
4740 	struct sctp_association *asoc;
4741 
4742 	if (len < sizeof (struct sctp_rtoinfo))
4743 		return -EINVAL;
4744 
4745 	len = sizeof(struct sctp_rtoinfo);
4746 
4747 	if (copy_from_user(&rtoinfo, optval, len))
4748 		return -EFAULT;
4749 
4750 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
4751 
4752 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
4753 		return -EINVAL;
4754 
4755 	/* Values corresponding to the specific association. */
4756 	if (asoc) {
4757 		rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
4758 		rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
4759 		rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
4760 	} else {
4761 		/* Values corresponding to the endpoint. */
4762 		struct sctp_sock *sp = sctp_sk(sk);
4763 
4764 		rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
4765 		rtoinfo.srto_max = sp->rtoinfo.srto_max;
4766 		rtoinfo.srto_min = sp->rtoinfo.srto_min;
4767 	}
4768 
4769 	if (put_user(len, optlen))
4770 		return -EFAULT;
4771 
4772 	if (copy_to_user(optval, &rtoinfo, len))
4773 		return -EFAULT;
4774 
4775 	return 0;
4776 }
4777 
4778 /*
4779  *
4780  * 7.1.2 SCTP_ASSOCINFO
4781  *
4782  * This option is used to tune the maximum retransmission attempts
4783  * of the association.
4784  * Returns an error if the new association retransmission value is
4785  * greater than the sum of the retransmission value  of the peer.
4786  * See [SCTP] for more information.
4787  *
4788  */
4789 static int sctp_getsockopt_associnfo(struct sock *sk, int len,
4790 				     char __user *optval,
4791 				     int __user *optlen)
4792 {
4793 
4794 	struct sctp_assocparams assocparams;
4795 	struct sctp_association *asoc;
4796 	struct list_head *pos;
4797 	int cnt = 0;
4798 
4799 	if (len < sizeof (struct sctp_assocparams))
4800 		return -EINVAL;
4801 
4802 	len = sizeof(struct sctp_assocparams);
4803 
4804 	if (copy_from_user(&assocparams, optval, len))
4805 		return -EFAULT;
4806 
4807 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
4808 
4809 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
4810 		return -EINVAL;
4811 
4812 	/* Values correspoinding to the specific association */
4813 	if (asoc) {
4814 		assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
4815 		assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
4816 		assocparams.sasoc_local_rwnd = asoc->a_rwnd;
4817 		assocparams.sasoc_cookie_life = (asoc->cookie_life.tv_sec
4818 						* 1000) +
4819 						(asoc->cookie_life.tv_usec
4820 						/ 1000);
4821 
4822 		list_for_each(pos, &asoc->peer.transport_addr_list) {
4823 			cnt ++;
4824 		}
4825 
4826 		assocparams.sasoc_number_peer_destinations = cnt;
4827 	} else {
4828 		/* Values corresponding to the endpoint */
4829 		struct sctp_sock *sp = sctp_sk(sk);
4830 
4831 		assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
4832 		assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
4833 		assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
4834 		assocparams.sasoc_cookie_life =
4835 					sp->assocparams.sasoc_cookie_life;
4836 		assocparams.sasoc_number_peer_destinations =
4837 					sp->assocparams.
4838 					sasoc_number_peer_destinations;
4839 	}
4840 
4841 	if (put_user(len, optlen))
4842 		return -EFAULT;
4843 
4844 	if (copy_to_user(optval, &assocparams, len))
4845 		return -EFAULT;
4846 
4847 	return 0;
4848 }
4849 
4850 /*
4851  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
4852  *
4853  * This socket option is a boolean flag which turns on or off mapped V4
4854  * addresses.  If this option is turned on and the socket is type
4855  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
4856  * If this option is turned off, then no mapping will be done of V4
4857  * addresses and a user will receive both PF_INET6 and PF_INET type
4858  * addresses on the socket.
4859  */
4860 static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
4861 				    char __user *optval, int __user *optlen)
4862 {
4863 	int val;
4864 	struct sctp_sock *sp = sctp_sk(sk);
4865 
4866 	if (len < sizeof(int))
4867 		return -EINVAL;
4868 
4869 	len = sizeof(int);
4870 	val = sp->v4mapped;
4871 	if (put_user(len, optlen))
4872 		return -EFAULT;
4873 	if (copy_to_user(optval, &val, len))
4874 		return -EFAULT;
4875 
4876 	return 0;
4877 }
4878 
4879 /*
4880  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
4881  * (chapter and verse is quoted at sctp_setsockopt_context())
4882  */
4883 static int sctp_getsockopt_context(struct sock *sk, int len,
4884 				   char __user *optval, int __user *optlen)
4885 {
4886 	struct sctp_assoc_value params;
4887 	struct sctp_sock *sp;
4888 	struct sctp_association *asoc;
4889 
4890 	if (len < sizeof(struct sctp_assoc_value))
4891 		return -EINVAL;
4892 
4893 	len = sizeof(struct sctp_assoc_value);
4894 
4895 	if (copy_from_user(&params, optval, len))
4896 		return -EFAULT;
4897 
4898 	sp = sctp_sk(sk);
4899 
4900 	if (params.assoc_id != 0) {
4901 		asoc = sctp_id2assoc(sk, params.assoc_id);
4902 		if (!asoc)
4903 			return -EINVAL;
4904 		params.assoc_value = asoc->default_rcv_context;
4905 	} else {
4906 		params.assoc_value = sp->default_rcv_context;
4907 	}
4908 
4909 	if (put_user(len, optlen))
4910 		return -EFAULT;
4911 	if (copy_to_user(optval, &params, len))
4912 		return -EFAULT;
4913 
4914 	return 0;
4915 }
4916 
4917 /*
4918  * 7.1.17 Set the maximum fragrmentation size (SCTP_MAXSEG)
4919  *
4920  * This socket option specifies the maximum size to put in any outgoing
4921  * SCTP chunk.  If a message is larger than this size it will be
4922  * fragmented by SCTP into the specified size.  Note that the underlying
4923  * SCTP implementation may fragment into smaller sized chunks when the
4924  * PMTU of the underlying association is smaller than the value set by
4925  * the user.
4926  */
4927 static int sctp_getsockopt_maxseg(struct sock *sk, int len,
4928 				  char __user *optval, int __user *optlen)
4929 {
4930 	int val;
4931 
4932 	if (len < sizeof(int))
4933 		return -EINVAL;
4934 
4935 	len = sizeof(int);
4936 
4937 	val = sctp_sk(sk)->user_frag;
4938 	if (put_user(len, optlen))
4939 		return -EFAULT;
4940 	if (copy_to_user(optval, &val, len))
4941 		return -EFAULT;
4942 
4943 	return 0;
4944 }
4945 
4946 /*
4947  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
4948  * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
4949  */
4950 static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
4951 					       char __user *optval, int __user *optlen)
4952 {
4953 	int val;
4954 
4955 	if (len < sizeof(int))
4956 		return -EINVAL;
4957 
4958 	len = sizeof(int);
4959 
4960 	val = sctp_sk(sk)->frag_interleave;
4961 	if (put_user(len, optlen))
4962 		return -EFAULT;
4963 	if (copy_to_user(optval, &val, len))
4964 		return -EFAULT;
4965 
4966 	return 0;
4967 }
4968 
4969 /*
4970  * 7.1.25.  Set or Get the sctp partial delivery point
4971  * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
4972  */
4973 static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
4974 						  char __user *optval,
4975 						  int __user *optlen)
4976 {
4977 	u32 val;
4978 
4979 	if (len < sizeof(u32))
4980 		return -EINVAL;
4981 
4982 	len = sizeof(u32);
4983 
4984 	val = sctp_sk(sk)->pd_point;
4985 	if (put_user(len, optlen))
4986 		return -EFAULT;
4987 	if (copy_to_user(optval, &val, len))
4988 		return -EFAULT;
4989 
4990 	return -ENOTSUPP;
4991 }
4992 
4993 /*
4994  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
4995  * (chapter and verse is quoted at sctp_setsockopt_maxburst())
4996  */
4997 static int sctp_getsockopt_maxburst(struct sock *sk, int len,
4998 				    char __user *optval,
4999 				    int __user *optlen)
5000 {
5001 	int val;
5002 
5003 	if (len < sizeof(int))
5004 		return -EINVAL;
5005 
5006 	len = sizeof(int);
5007 
5008 	val = sctp_sk(sk)->max_burst;
5009 	if (put_user(len, optlen))
5010 		return -EFAULT;
5011 	if (copy_to_user(optval, &val, len))
5012 		return -EFAULT;
5013 
5014 	return -ENOTSUPP;
5015 }
5016 
5017 static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
5018 				    char __user *optval, int __user *optlen)
5019 {
5020 	struct sctp_hmac_algo_param *hmacs;
5021 	__u16 param_len;
5022 
5023 	hmacs = sctp_sk(sk)->ep->auth_hmacs_list;
5024 	param_len = ntohs(hmacs->param_hdr.length);
5025 
5026 	if (len < param_len)
5027 		return -EINVAL;
5028 	if (put_user(len, optlen))
5029 		return -EFAULT;
5030 	if (copy_to_user(optval, hmacs->hmac_ids, len))
5031 		return -EFAULT;
5032 
5033 	return 0;
5034 }
5035 
5036 static int sctp_getsockopt_active_key(struct sock *sk, int len,
5037 				    char __user *optval, int __user *optlen)
5038 {
5039 	struct sctp_authkeyid val;
5040 	struct sctp_association *asoc;
5041 
5042 	if (len < sizeof(struct sctp_authkeyid))
5043 		return -EINVAL;
5044 	if (copy_from_user(&val, optval, sizeof(struct sctp_authkeyid)))
5045 		return -EFAULT;
5046 
5047 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
5048 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
5049 		return -EINVAL;
5050 
5051 	if (asoc)
5052 		val.scact_keynumber = asoc->active_key_id;
5053 	else
5054 		val.scact_keynumber = sctp_sk(sk)->ep->active_key_id;
5055 
5056 	return 0;
5057 }
5058 
5059 static int sctp_getsockopt_peer_auth_chunks(struct sock *sk, int len,
5060 				    char __user *optval, int __user *optlen)
5061 {
5062 	struct sctp_authchunks __user *p = (void __user *)optval;
5063 	struct sctp_authchunks val;
5064 	struct sctp_association *asoc;
5065 	struct sctp_chunks_param *ch;
5066 	char __user *to;
5067 
5068 	if (len <= sizeof(struct sctp_authchunks))
5069 		return -EINVAL;
5070 
5071 	if (copy_from_user(&val, p, sizeof(struct sctp_authchunks)))
5072 		return -EFAULT;
5073 
5074 	to = p->gauth_chunks;
5075 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5076 	if (!asoc)
5077 		return -EINVAL;
5078 
5079 	ch = asoc->peer.peer_chunks;
5080 
5081 	/* See if the user provided enough room for all the data */
5082 	if (len < ntohs(ch->param_hdr.length))
5083 		return -EINVAL;
5084 
5085 	len = ntohs(ch->param_hdr.length);
5086 	if (put_user(len, optlen))
5087 		return -EFAULT;
5088 	if (copy_to_user(to, ch->chunks, len))
5089 		return -EFAULT;
5090 
5091 	return 0;
5092 }
5093 
5094 static int sctp_getsockopt_local_auth_chunks(struct sock *sk, int len,
5095 				    char __user *optval, int __user *optlen)
5096 {
5097 	struct sctp_authchunks __user *p = (void __user *)optval;
5098 	struct sctp_authchunks val;
5099 	struct sctp_association *asoc;
5100 	struct sctp_chunks_param *ch;
5101 	char __user *to;
5102 
5103 	if (len <= sizeof(struct sctp_authchunks))
5104 		return -EINVAL;
5105 
5106 	if (copy_from_user(&val, p, sizeof(struct sctp_authchunks)))
5107 		return -EFAULT;
5108 
5109 	to = p->gauth_chunks;
5110 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5111 	if (!asoc && val.gauth_assoc_id && sctp_style(sk, UDP))
5112 		return -EINVAL;
5113 
5114 	if (asoc)
5115 		ch = (struct sctp_chunks_param*)asoc->c.auth_chunks;
5116 	else
5117 		ch = sctp_sk(sk)->ep->auth_chunk_list;
5118 
5119 	if (len < ntohs(ch->param_hdr.length))
5120 		return -EINVAL;
5121 
5122 	len = ntohs(ch->param_hdr.length);
5123 	if (put_user(len, optlen))
5124 		return -EFAULT;
5125 	if (copy_to_user(to, ch->chunks, len))
5126 		return -EFAULT;
5127 
5128 	return 0;
5129 }
5130 
5131 SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
5132 				char __user *optval, int __user *optlen)
5133 {
5134 	int retval = 0;
5135 	int len;
5136 
5137 	SCTP_DEBUG_PRINTK("sctp_getsockopt(sk: %p... optname: %d)\n",
5138 			  sk, optname);
5139 
5140 	/* I can hardly begin to describe how wrong this is.  This is
5141 	 * so broken as to be worse than useless.  The API draft
5142 	 * REALLY is NOT helpful here...  I am not convinced that the
5143 	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
5144 	 * are at all well-founded.
5145 	 */
5146 	if (level != SOL_SCTP) {
5147 		struct sctp_af *af = sctp_sk(sk)->pf->af;
5148 
5149 		retval = af->getsockopt(sk, level, optname, optval, optlen);
5150 		return retval;
5151 	}
5152 
5153 	if (get_user(len, optlen))
5154 		return -EFAULT;
5155 
5156 	sctp_lock_sock(sk);
5157 
5158 	switch (optname) {
5159 	case SCTP_STATUS:
5160 		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
5161 		break;
5162 	case SCTP_DISABLE_FRAGMENTS:
5163 		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
5164 							   optlen);
5165 		break;
5166 	case SCTP_EVENTS:
5167 		retval = sctp_getsockopt_events(sk, len, optval, optlen);
5168 		break;
5169 	case SCTP_AUTOCLOSE:
5170 		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
5171 		break;
5172 	case SCTP_SOCKOPT_PEELOFF:
5173 		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
5174 		break;
5175 	case SCTP_PEER_ADDR_PARAMS:
5176 		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
5177 							  optlen);
5178 		break;
5179 	case SCTP_DELAYED_ACK_TIME:
5180 		retval = sctp_getsockopt_delayed_ack_time(sk, len, optval,
5181 							  optlen);
5182 		break;
5183 	case SCTP_INITMSG:
5184 		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
5185 		break;
5186 	case SCTP_GET_PEER_ADDRS_NUM_OLD:
5187 		retval = sctp_getsockopt_peer_addrs_num_old(sk, len, optval,
5188 							    optlen);
5189 		break;
5190 	case SCTP_GET_LOCAL_ADDRS_NUM_OLD:
5191 		retval = sctp_getsockopt_local_addrs_num_old(sk, len, optval,
5192 							     optlen);
5193 		break;
5194 	case SCTP_GET_PEER_ADDRS_OLD:
5195 		retval = sctp_getsockopt_peer_addrs_old(sk, len, optval,
5196 							optlen);
5197 		break;
5198 	case SCTP_GET_LOCAL_ADDRS_OLD:
5199 		retval = sctp_getsockopt_local_addrs_old(sk, len, optval,
5200 							 optlen);
5201 		break;
5202 	case SCTP_GET_PEER_ADDRS:
5203 		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
5204 						    optlen);
5205 		break;
5206 	case SCTP_GET_LOCAL_ADDRS:
5207 		retval = sctp_getsockopt_local_addrs(sk, len, optval,
5208 						     optlen);
5209 		break;
5210 	case SCTP_DEFAULT_SEND_PARAM:
5211 		retval = sctp_getsockopt_default_send_param(sk, len,
5212 							    optval, optlen);
5213 		break;
5214 	case SCTP_PRIMARY_ADDR:
5215 		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
5216 		break;
5217 	case SCTP_NODELAY:
5218 		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
5219 		break;
5220 	case SCTP_RTOINFO:
5221 		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
5222 		break;
5223 	case SCTP_ASSOCINFO:
5224 		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
5225 		break;
5226 	case SCTP_I_WANT_MAPPED_V4_ADDR:
5227 		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
5228 		break;
5229 	case SCTP_MAXSEG:
5230 		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
5231 		break;
5232 	case SCTP_GET_PEER_ADDR_INFO:
5233 		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
5234 							optlen);
5235 		break;
5236 	case SCTP_ADAPTATION_LAYER:
5237 		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
5238 							optlen);
5239 		break;
5240 	case SCTP_CONTEXT:
5241 		retval = sctp_getsockopt_context(sk, len, optval, optlen);
5242 		break;
5243 	case SCTP_FRAGMENT_INTERLEAVE:
5244 		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
5245 							     optlen);
5246 		break;
5247 	case SCTP_PARTIAL_DELIVERY_POINT:
5248 		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
5249 								optlen);
5250 		break;
5251 	case SCTP_MAX_BURST:
5252 		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
5253 		break;
5254 	case SCTP_AUTH_KEY:
5255 	case SCTP_AUTH_CHUNK:
5256 	case SCTP_AUTH_DELETE_KEY:
5257 		retval = -EOPNOTSUPP;
5258 		break;
5259 	case SCTP_HMAC_IDENT:
5260 		retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
5261 		break;
5262 	case SCTP_AUTH_ACTIVE_KEY:
5263 		retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
5264 		break;
5265 	case SCTP_PEER_AUTH_CHUNKS:
5266 		retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
5267 							optlen);
5268 		break;
5269 	case SCTP_LOCAL_AUTH_CHUNKS:
5270 		retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
5271 							optlen);
5272 		break;
5273 	default:
5274 		retval = -ENOPROTOOPT;
5275 		break;
5276 	}
5277 
5278 	sctp_release_sock(sk);
5279 	return retval;
5280 }
5281 
5282 static void sctp_hash(struct sock *sk)
5283 {
5284 	/* STUB */
5285 }
5286 
5287 static void sctp_unhash(struct sock *sk)
5288 {
5289 	/* STUB */
5290 }
5291 
5292 /* Check if port is acceptable.  Possibly find first available port.
5293  *
5294  * The port hash table (contained in the 'global' SCTP protocol storage
5295  * returned by struct sctp_protocol *sctp_get_protocol()). The hash
5296  * table is an array of 4096 lists (sctp_bind_hashbucket). Each
5297  * list (the list number is the port number hashed out, so as you
5298  * would expect from a hash function, all the ports in a given list have
5299  * such a number that hashes out to the same list number; you were
5300  * expecting that, right?); so each list has a set of ports, with a
5301  * link to the socket (struct sock) that uses it, the port number and
5302  * a fastreuse flag (FIXME: NPI ipg).
5303  */
5304 static struct sctp_bind_bucket *sctp_bucket_create(
5305 	struct sctp_bind_hashbucket *head, unsigned short snum);
5306 
5307 static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
5308 {
5309 	struct sctp_bind_hashbucket *head; /* hash list */
5310 	struct sctp_bind_bucket *pp; /* hash list port iterator */
5311 	struct hlist_node *node;
5312 	unsigned short snum;
5313 	int ret;
5314 
5315 	snum = ntohs(addr->v4.sin_port);
5316 
5317 	SCTP_DEBUG_PRINTK("sctp_get_port() begins, snum=%d\n", snum);
5318 	sctp_local_bh_disable();
5319 
5320 	if (snum == 0) {
5321 		/* Search for an available port. */
5322 		int low, high, remaining, index;
5323 		unsigned int rover;
5324 
5325 		inet_get_local_port_range(&low, &high);
5326 		remaining = (high - low) + 1;
5327 		rover = net_random() % remaining + low;
5328 
5329 		do {
5330 			rover++;
5331 			if ((rover < low) || (rover > high))
5332 				rover = low;
5333 			index = sctp_phashfn(rover);
5334 			head = &sctp_port_hashtable[index];
5335 			sctp_spin_lock(&head->lock);
5336 			sctp_for_each_hentry(pp, node, &head->chain)
5337 				if (pp->port == rover)
5338 					goto next;
5339 			break;
5340 		next:
5341 			sctp_spin_unlock(&head->lock);
5342 		} while (--remaining > 0);
5343 
5344 		/* Exhausted local port range during search? */
5345 		ret = 1;
5346 		if (remaining <= 0)
5347 			goto fail;
5348 
5349 		/* OK, here is the one we will use.  HEAD (the port
5350 		 * hash table list entry) is non-NULL and we hold it's
5351 		 * mutex.
5352 		 */
5353 		snum = rover;
5354 	} else {
5355 		/* We are given an specific port number; we verify
5356 		 * that it is not being used. If it is used, we will
5357 		 * exahust the search in the hash list corresponding
5358 		 * to the port number (snum) - we detect that with the
5359 		 * port iterator, pp being NULL.
5360 		 */
5361 		head = &sctp_port_hashtable[sctp_phashfn(snum)];
5362 		sctp_spin_lock(&head->lock);
5363 		sctp_for_each_hentry(pp, node, &head->chain) {
5364 			if (pp->port == snum)
5365 				goto pp_found;
5366 		}
5367 	}
5368 	pp = NULL;
5369 	goto pp_not_found;
5370 pp_found:
5371 	if (!hlist_empty(&pp->owner)) {
5372 		/* We had a port hash table hit - there is an
5373 		 * available port (pp != NULL) and it is being
5374 		 * used by other socket (pp->owner not empty); that other
5375 		 * socket is going to be sk2.
5376 		 */
5377 		int reuse = sk->sk_reuse;
5378 		struct sock *sk2;
5379 		struct hlist_node *node;
5380 
5381 		SCTP_DEBUG_PRINTK("sctp_get_port() found a possible match\n");
5382 		if (pp->fastreuse && sk->sk_reuse &&
5383 			sk->sk_state != SCTP_SS_LISTENING)
5384 			goto success;
5385 
5386 		/* Run through the list of sockets bound to the port
5387 		 * (pp->port) [via the pointers bind_next and
5388 		 * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
5389 		 * we get the endpoint they describe and run through
5390 		 * the endpoint's list of IP (v4 or v6) addresses,
5391 		 * comparing each of the addresses with the address of
5392 		 * the socket sk. If we find a match, then that means
5393 		 * that this port/socket (sk) combination are already
5394 		 * in an endpoint.
5395 		 */
5396 		sk_for_each_bound(sk2, node, &pp->owner) {
5397 			struct sctp_endpoint *ep2;
5398 			ep2 = sctp_sk(sk2)->ep;
5399 
5400 			if (reuse && sk2->sk_reuse &&
5401 			    sk2->sk_state != SCTP_SS_LISTENING)
5402 				continue;
5403 
5404 			if (sctp_bind_addr_match(&ep2->base.bind_addr, addr,
5405 						 sctp_sk(sk))) {
5406 				ret = (long)sk2;
5407 				goto fail_unlock;
5408 			}
5409 		}
5410 		SCTP_DEBUG_PRINTK("sctp_get_port(): Found a match\n");
5411 	}
5412 pp_not_found:
5413 	/* If there was a hash table miss, create a new port.  */
5414 	ret = 1;
5415 	if (!pp && !(pp = sctp_bucket_create(head, snum)))
5416 		goto fail_unlock;
5417 
5418 	/* In either case (hit or miss), make sure fastreuse is 1 only
5419 	 * if sk->sk_reuse is too (that is, if the caller requested
5420 	 * SO_REUSEADDR on this socket -sk-).
5421 	 */
5422 	if (hlist_empty(&pp->owner)) {
5423 		if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
5424 			pp->fastreuse = 1;
5425 		else
5426 			pp->fastreuse = 0;
5427 	} else if (pp->fastreuse &&
5428 		(!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
5429 		pp->fastreuse = 0;
5430 
5431 	/* We are set, so fill up all the data in the hash table
5432 	 * entry, tie the socket list information with the rest of the
5433 	 * sockets FIXME: Blurry, NPI (ipg).
5434 	 */
5435 success:
5436 	if (!sctp_sk(sk)->bind_hash) {
5437 		inet_sk(sk)->num = snum;
5438 		sk_add_bind_node(sk, &pp->owner);
5439 		sctp_sk(sk)->bind_hash = pp;
5440 	}
5441 	ret = 0;
5442 
5443 fail_unlock:
5444 	sctp_spin_unlock(&head->lock);
5445 
5446 fail:
5447 	sctp_local_bh_enable();
5448 	return ret;
5449 }
5450 
5451 /* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
5452  * port is requested.
5453  */
5454 static int sctp_get_port(struct sock *sk, unsigned short snum)
5455 {
5456 	long ret;
5457 	union sctp_addr addr;
5458 	struct sctp_af *af = sctp_sk(sk)->pf->af;
5459 
5460 	/* Set up a dummy address struct from the sk. */
5461 	af->from_sk(&addr, sk);
5462 	addr.v4.sin_port = htons(snum);
5463 
5464 	/* Note: sk->sk_num gets filled in if ephemeral port request. */
5465 	ret = sctp_get_port_local(sk, &addr);
5466 
5467 	return (ret ? 1 : 0);
5468 }
5469 
5470 /*
5471  * 3.1.3 listen() - UDP Style Syntax
5472  *
5473  *   By default, new associations are not accepted for UDP style sockets.
5474  *   An application uses listen() to mark a socket as being able to
5475  *   accept new associations.
5476  */
5477 SCTP_STATIC int sctp_seqpacket_listen(struct sock *sk, int backlog)
5478 {
5479 	struct sctp_sock *sp = sctp_sk(sk);
5480 	struct sctp_endpoint *ep = sp->ep;
5481 
5482 	/* Only UDP style sockets that are not peeled off are allowed to
5483 	 * listen().
5484 	 */
5485 	if (!sctp_style(sk, UDP))
5486 		return -EINVAL;
5487 
5488 	/* If backlog is zero, disable listening. */
5489 	if (!backlog) {
5490 		if (sctp_sstate(sk, CLOSED))
5491 			return 0;
5492 
5493 		sctp_unhash_endpoint(ep);
5494 		sk->sk_state = SCTP_SS_CLOSED;
5495 		return 0;
5496 	}
5497 
5498 	/* Return if we are already listening. */
5499 	if (sctp_sstate(sk, LISTENING))
5500 		return 0;
5501 
5502 	/*
5503 	 * If a bind() or sctp_bindx() is not called prior to a listen()
5504 	 * call that allows new associations to be accepted, the system
5505 	 * picks an ephemeral port and will choose an address set equivalent
5506 	 * to binding with a wildcard address.
5507 	 *
5508 	 * This is not currently spelled out in the SCTP sockets
5509 	 * extensions draft, but follows the practice as seen in TCP
5510 	 * sockets.
5511 	 *
5512 	 * Additionally, turn off fastreuse flag since we are not listening
5513 	 */
5514 	sk->sk_state = SCTP_SS_LISTENING;
5515 	if (!ep->base.bind_addr.port) {
5516 		if (sctp_autobind(sk))
5517 			return -EAGAIN;
5518 	} else
5519 		sctp_sk(sk)->bind_hash->fastreuse = 0;
5520 
5521 	sctp_hash_endpoint(ep);
5522 	return 0;
5523 }
5524 
5525 /*
5526  * 4.1.3 listen() - TCP Style Syntax
5527  *
5528  *   Applications uses listen() to ready the SCTP endpoint for accepting
5529  *   inbound associations.
5530  */
5531 SCTP_STATIC int sctp_stream_listen(struct sock *sk, int backlog)
5532 {
5533 	struct sctp_sock *sp = sctp_sk(sk);
5534 	struct sctp_endpoint *ep = sp->ep;
5535 
5536 	/* If backlog is zero, disable listening. */
5537 	if (!backlog) {
5538 		if (sctp_sstate(sk, CLOSED))
5539 			return 0;
5540 
5541 		sctp_unhash_endpoint(ep);
5542 		sk->sk_state = SCTP_SS_CLOSED;
5543 		return 0;
5544 	}
5545 
5546 	if (sctp_sstate(sk, LISTENING))
5547 		return 0;
5548 
5549 	/*
5550 	 * If a bind() or sctp_bindx() is not called prior to a listen()
5551 	 * call that allows new associations to be accepted, the system
5552 	 * picks an ephemeral port and will choose an address set equivalent
5553 	 * to binding with a wildcard address.
5554 	 *
5555 	 * This is not currently spelled out in the SCTP sockets
5556 	 * extensions draft, but follows the practice as seen in TCP
5557 	 * sockets.
5558 	 */
5559 	sk->sk_state = SCTP_SS_LISTENING;
5560 	if (!ep->base.bind_addr.port) {
5561 		if (sctp_autobind(sk))
5562 			return -EAGAIN;
5563 	} else
5564 		sctp_sk(sk)->bind_hash->fastreuse = 0;
5565 
5566 	sk->sk_max_ack_backlog = backlog;
5567 	sctp_hash_endpoint(ep);
5568 	return 0;
5569 }
5570 
5571 /*
5572  *  Move a socket to LISTENING state.
5573  */
5574 int sctp_inet_listen(struct socket *sock, int backlog)
5575 {
5576 	struct sock *sk = sock->sk;
5577 	struct crypto_hash *tfm = NULL;
5578 	int err = -EINVAL;
5579 
5580 	if (unlikely(backlog < 0))
5581 		goto out;
5582 
5583 	sctp_lock_sock(sk);
5584 
5585 	if (sock->state != SS_UNCONNECTED)
5586 		goto out;
5587 
5588 	/* Allocate HMAC for generating cookie. */
5589 	if (sctp_hmac_alg) {
5590 		tfm = crypto_alloc_hash(sctp_hmac_alg, 0, CRYPTO_ALG_ASYNC);
5591 		if (IS_ERR(tfm)) {
5592 			if (net_ratelimit()) {
5593 				printk(KERN_INFO
5594 				       "SCTP: failed to load transform for %s: %ld\n",
5595 					sctp_hmac_alg, PTR_ERR(tfm));
5596 			}
5597 			err = -ENOSYS;
5598 			goto out;
5599 		}
5600 	}
5601 
5602 	switch (sock->type) {
5603 	case SOCK_SEQPACKET:
5604 		err = sctp_seqpacket_listen(sk, backlog);
5605 		break;
5606 	case SOCK_STREAM:
5607 		err = sctp_stream_listen(sk, backlog);
5608 		break;
5609 	default:
5610 		break;
5611 	}
5612 
5613 	if (err)
5614 		goto cleanup;
5615 
5616 	/* Store away the transform reference. */
5617 	sctp_sk(sk)->hmac = tfm;
5618 out:
5619 	sctp_release_sock(sk);
5620 	return err;
5621 cleanup:
5622 	crypto_free_hash(tfm);
5623 	goto out;
5624 }
5625 
5626 /*
5627  * This function is done by modeling the current datagram_poll() and the
5628  * tcp_poll().  Note that, based on these implementations, we don't
5629  * lock the socket in this function, even though it seems that,
5630  * ideally, locking or some other mechanisms can be used to ensure
5631  * the integrity of the counters (sndbuf and wmem_alloc) used
5632  * in this place.  We assume that we don't need locks either until proven
5633  * otherwise.
5634  *
5635  * Another thing to note is that we include the Async I/O support
5636  * here, again, by modeling the current TCP/UDP code.  We don't have
5637  * a good way to test with it yet.
5638  */
5639 unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
5640 {
5641 	struct sock *sk = sock->sk;
5642 	struct sctp_sock *sp = sctp_sk(sk);
5643 	unsigned int mask;
5644 
5645 	poll_wait(file, sk->sk_sleep, wait);
5646 
5647 	/* A TCP-style listening socket becomes readable when the accept queue
5648 	 * is not empty.
5649 	 */
5650 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
5651 		return (!list_empty(&sp->ep->asocs)) ?
5652 			(POLLIN | POLLRDNORM) : 0;
5653 
5654 	mask = 0;
5655 
5656 	/* Is there any exceptional events?  */
5657 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
5658 		mask |= POLLERR;
5659 	if (sk->sk_shutdown & RCV_SHUTDOWN)
5660 		mask |= POLLRDHUP;
5661 	if (sk->sk_shutdown == SHUTDOWN_MASK)
5662 		mask |= POLLHUP;
5663 
5664 	/* Is it readable?  Reconsider this code with TCP-style support.  */
5665 	if (!skb_queue_empty(&sk->sk_receive_queue) ||
5666 	    (sk->sk_shutdown & RCV_SHUTDOWN))
5667 		mask |= POLLIN | POLLRDNORM;
5668 
5669 	/* The association is either gone or not ready.  */
5670 	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
5671 		return mask;
5672 
5673 	/* Is it writable?  */
5674 	if (sctp_writeable(sk)) {
5675 		mask |= POLLOUT | POLLWRNORM;
5676 	} else {
5677 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
5678 		/*
5679 		 * Since the socket is not locked, the buffer
5680 		 * might be made available after the writeable check and
5681 		 * before the bit is set.  This could cause a lost I/O
5682 		 * signal.  tcp_poll() has a race breaker for this race
5683 		 * condition.  Based on their implementation, we put
5684 		 * in the following code to cover it as well.
5685 		 */
5686 		if (sctp_writeable(sk))
5687 			mask |= POLLOUT | POLLWRNORM;
5688 	}
5689 	return mask;
5690 }
5691 
5692 /********************************************************************
5693  * 2nd Level Abstractions
5694  ********************************************************************/
5695 
5696 static struct sctp_bind_bucket *sctp_bucket_create(
5697 	struct sctp_bind_hashbucket *head, unsigned short snum)
5698 {
5699 	struct sctp_bind_bucket *pp;
5700 
5701 	pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
5702 	SCTP_DBG_OBJCNT_INC(bind_bucket);
5703 	if (pp) {
5704 		pp->port = snum;
5705 		pp->fastreuse = 0;
5706 		INIT_HLIST_HEAD(&pp->owner);
5707 		hlist_add_head(&pp->node, &head->chain);
5708 	}
5709 	return pp;
5710 }
5711 
5712 /* Caller must hold hashbucket lock for this tb with local BH disabled */
5713 static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
5714 {
5715 	if (pp && hlist_empty(&pp->owner)) {
5716 		__hlist_del(&pp->node);
5717 		kmem_cache_free(sctp_bucket_cachep, pp);
5718 		SCTP_DBG_OBJCNT_DEC(bind_bucket);
5719 	}
5720 }
5721 
5722 /* Release this socket's reference to a local port.  */
5723 static inline void __sctp_put_port(struct sock *sk)
5724 {
5725 	struct sctp_bind_hashbucket *head =
5726 		&sctp_port_hashtable[sctp_phashfn(inet_sk(sk)->num)];
5727 	struct sctp_bind_bucket *pp;
5728 
5729 	sctp_spin_lock(&head->lock);
5730 	pp = sctp_sk(sk)->bind_hash;
5731 	__sk_del_bind_node(sk);
5732 	sctp_sk(sk)->bind_hash = NULL;
5733 	inet_sk(sk)->num = 0;
5734 	sctp_bucket_destroy(pp);
5735 	sctp_spin_unlock(&head->lock);
5736 }
5737 
5738 void sctp_put_port(struct sock *sk)
5739 {
5740 	sctp_local_bh_disable();
5741 	__sctp_put_port(sk);
5742 	sctp_local_bh_enable();
5743 }
5744 
5745 /*
5746  * The system picks an ephemeral port and choose an address set equivalent
5747  * to binding with a wildcard address.
5748  * One of those addresses will be the primary address for the association.
5749  * This automatically enables the multihoming capability of SCTP.
5750  */
5751 static int sctp_autobind(struct sock *sk)
5752 {
5753 	union sctp_addr autoaddr;
5754 	struct sctp_af *af;
5755 	__be16 port;
5756 
5757 	/* Initialize a local sockaddr structure to INADDR_ANY. */
5758 	af = sctp_sk(sk)->pf->af;
5759 
5760 	port = htons(inet_sk(sk)->num);
5761 	af->inaddr_any(&autoaddr, port);
5762 
5763 	return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
5764 }
5765 
5766 /* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
5767  *
5768  * From RFC 2292
5769  * 4.2 The cmsghdr Structure *
5770  *
5771  * When ancillary data is sent or received, any number of ancillary data
5772  * objects can be specified by the msg_control and msg_controllen members of
5773  * the msghdr structure, because each object is preceded by
5774  * a cmsghdr structure defining the object's length (the cmsg_len member).
5775  * Historically Berkeley-derived implementations have passed only one object
5776  * at a time, but this API allows multiple objects to be
5777  * passed in a single call to sendmsg() or recvmsg(). The following example
5778  * shows two ancillary data objects in a control buffer.
5779  *
5780  *   |<--------------------------- msg_controllen -------------------------->|
5781  *   |                                                                       |
5782  *
5783  *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
5784  *
5785  *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
5786  *   |                                   |                                   |
5787  *
5788  *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
5789  *
5790  *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
5791  *   |                                |  |                                |  |
5792  *
5793  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5794  *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
5795  *
5796  *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
5797  *
5798  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5799  *    ^
5800  *    |
5801  *
5802  * msg_control
5803  * points here
5804  */
5805 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *msg,
5806 				  sctp_cmsgs_t *cmsgs)
5807 {
5808 	struct cmsghdr *cmsg;
5809 
5810 	for (cmsg = CMSG_FIRSTHDR(msg);
5811 	     cmsg != NULL;
5812 	     cmsg = CMSG_NXTHDR((struct msghdr*)msg, cmsg)) {
5813 		if (!CMSG_OK(msg, cmsg))
5814 			return -EINVAL;
5815 
5816 		/* Should we parse this header or ignore?  */
5817 		if (cmsg->cmsg_level != IPPROTO_SCTP)
5818 			continue;
5819 
5820 		/* Strictly check lengths following example in SCM code.  */
5821 		switch (cmsg->cmsg_type) {
5822 		case SCTP_INIT:
5823 			/* SCTP Socket API Extension
5824 			 * 5.2.1 SCTP Initiation Structure (SCTP_INIT)
5825 			 *
5826 			 * This cmsghdr structure provides information for
5827 			 * initializing new SCTP associations with sendmsg().
5828 			 * The SCTP_INITMSG socket option uses this same data
5829 			 * structure.  This structure is not used for
5830 			 * recvmsg().
5831 			 *
5832 			 * cmsg_level    cmsg_type      cmsg_data[]
5833 			 * ------------  ------------   ----------------------
5834 			 * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
5835 			 */
5836 			if (cmsg->cmsg_len !=
5837 			    CMSG_LEN(sizeof(struct sctp_initmsg)))
5838 				return -EINVAL;
5839 			cmsgs->init = (struct sctp_initmsg *)CMSG_DATA(cmsg);
5840 			break;
5841 
5842 		case SCTP_SNDRCV:
5843 			/* SCTP Socket API Extension
5844 			 * 5.2.2 SCTP Header Information Structure(SCTP_SNDRCV)
5845 			 *
5846 			 * This cmsghdr structure specifies SCTP options for
5847 			 * sendmsg() and describes SCTP header information
5848 			 * about a received message through recvmsg().
5849 			 *
5850 			 * cmsg_level    cmsg_type      cmsg_data[]
5851 			 * ------------  ------------   ----------------------
5852 			 * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
5853 			 */
5854 			if (cmsg->cmsg_len !=
5855 			    CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
5856 				return -EINVAL;
5857 
5858 			cmsgs->info =
5859 				(struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
5860 
5861 			/* Minimally, validate the sinfo_flags. */
5862 			if (cmsgs->info->sinfo_flags &
5863 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
5864 			      SCTP_ABORT | SCTP_EOF))
5865 				return -EINVAL;
5866 			break;
5867 
5868 		default:
5869 			return -EINVAL;
5870 		}
5871 	}
5872 	return 0;
5873 }
5874 
5875 /*
5876  * Wait for a packet..
5877  * Note: This function is the same function as in core/datagram.c
5878  * with a few modifications to make lksctp work.
5879  */
5880 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p)
5881 {
5882 	int error;
5883 	DEFINE_WAIT(wait);
5884 
5885 	prepare_to_wait_exclusive(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
5886 
5887 	/* Socket errors? */
5888 	error = sock_error(sk);
5889 	if (error)
5890 		goto out;
5891 
5892 	if (!skb_queue_empty(&sk->sk_receive_queue))
5893 		goto ready;
5894 
5895 	/* Socket shut down?  */
5896 	if (sk->sk_shutdown & RCV_SHUTDOWN)
5897 		goto out;
5898 
5899 	/* Sequenced packets can come disconnected.  If so we report the
5900 	 * problem.
5901 	 */
5902 	error = -ENOTCONN;
5903 
5904 	/* Is there a good reason to think that we may receive some data?  */
5905 	if (list_empty(&sctp_sk(sk)->ep->asocs) && !sctp_sstate(sk, LISTENING))
5906 		goto out;
5907 
5908 	/* Handle signals.  */
5909 	if (signal_pending(current))
5910 		goto interrupted;
5911 
5912 	/* Let another process have a go.  Since we are going to sleep
5913 	 * anyway.  Note: This may cause odd behaviors if the message
5914 	 * does not fit in the user's buffer, but this seems to be the
5915 	 * only way to honor MSG_DONTWAIT realistically.
5916 	 */
5917 	sctp_release_sock(sk);
5918 	*timeo_p = schedule_timeout(*timeo_p);
5919 	sctp_lock_sock(sk);
5920 
5921 ready:
5922 	finish_wait(sk->sk_sleep, &wait);
5923 	return 0;
5924 
5925 interrupted:
5926 	error = sock_intr_errno(*timeo_p);
5927 
5928 out:
5929 	finish_wait(sk->sk_sleep, &wait);
5930 	*err = error;
5931 	return error;
5932 }
5933 
5934 /* Receive a datagram.
5935  * Note: This is pretty much the same routine as in core/datagram.c
5936  * with a few changes to make lksctp work.
5937  */
5938 static struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
5939 					      int noblock, int *err)
5940 {
5941 	int error;
5942 	struct sk_buff *skb;
5943 	long timeo;
5944 
5945 	timeo = sock_rcvtimeo(sk, noblock);
5946 
5947 	SCTP_DEBUG_PRINTK("Timeout: timeo: %ld, MAX: %ld.\n",
5948 			  timeo, MAX_SCHEDULE_TIMEOUT);
5949 
5950 	do {
5951 		/* Again only user level code calls this function,
5952 		 * so nothing interrupt level
5953 		 * will suddenly eat the receive_queue.
5954 		 *
5955 		 *  Look at current nfs client by the way...
5956 		 *  However, this function was corrent in any case. 8)
5957 		 */
5958 		if (flags & MSG_PEEK) {
5959 			spin_lock_bh(&sk->sk_receive_queue.lock);
5960 			skb = skb_peek(&sk->sk_receive_queue);
5961 			if (skb)
5962 				atomic_inc(&skb->users);
5963 			spin_unlock_bh(&sk->sk_receive_queue.lock);
5964 		} else {
5965 			skb = skb_dequeue(&sk->sk_receive_queue);
5966 		}
5967 
5968 		if (skb)
5969 			return skb;
5970 
5971 		/* Caller is allowed not to check sk->sk_err before calling. */
5972 		error = sock_error(sk);
5973 		if (error)
5974 			goto no_packet;
5975 
5976 		if (sk->sk_shutdown & RCV_SHUTDOWN)
5977 			break;
5978 
5979 		/* User doesn't want to wait.  */
5980 		error = -EAGAIN;
5981 		if (!timeo)
5982 			goto no_packet;
5983 	} while (sctp_wait_for_packet(sk, err, &timeo) == 0);
5984 
5985 	return NULL;
5986 
5987 no_packet:
5988 	*err = error;
5989 	return NULL;
5990 }
5991 
5992 /* If sndbuf has changed, wake up per association sndbuf waiters.  */
5993 static void __sctp_write_space(struct sctp_association *asoc)
5994 {
5995 	struct sock *sk = asoc->base.sk;
5996 	struct socket *sock = sk->sk_socket;
5997 
5998 	if ((sctp_wspace(asoc) > 0) && sock) {
5999 		if (waitqueue_active(&asoc->wait))
6000 			wake_up_interruptible(&asoc->wait);
6001 
6002 		if (sctp_writeable(sk)) {
6003 			if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
6004 				wake_up_interruptible(sk->sk_sleep);
6005 
6006 			/* Note that we try to include the Async I/O support
6007 			 * here by modeling from the current TCP/UDP code.
6008 			 * We have not tested with it yet.
6009 			 */
6010 			if (sock->fasync_list &&
6011 			    !(sk->sk_shutdown & SEND_SHUTDOWN))
6012 				sock_wake_async(sock,
6013 						SOCK_WAKE_SPACE, POLL_OUT);
6014 		}
6015 	}
6016 }
6017 
6018 /* Do accounting for the sndbuf space.
6019  * Decrement the used sndbuf space of the corresponding association by the
6020  * data size which was just transmitted(freed).
6021  */
6022 static void sctp_wfree(struct sk_buff *skb)
6023 {
6024 	struct sctp_association *asoc;
6025 	struct sctp_chunk *chunk;
6026 	struct sock *sk;
6027 
6028 	/* Get the saved chunk pointer.  */
6029 	chunk = *((struct sctp_chunk **)(skb->cb));
6030 	asoc = chunk->asoc;
6031 	sk = asoc->base.sk;
6032 	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
6033 				sizeof(struct sk_buff) +
6034 				sizeof(struct sctp_chunk);
6035 
6036 	atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
6037 
6038 	/*
6039 	 * This undoes what is done via sctp_set_owner_w and sk_mem_charge
6040 	 */
6041 	sk->sk_wmem_queued   -= skb->truesize;
6042 	sk_mem_uncharge(sk, skb->truesize);
6043 
6044 	sock_wfree(skb);
6045 	__sctp_write_space(asoc);
6046 
6047 	sctp_association_put(asoc);
6048 }
6049 
6050 /* Do accounting for the receive space on the socket.
6051  * Accounting for the association is done in ulpevent.c
6052  * We set this as a destructor for the cloned data skbs so that
6053  * accounting is done at the correct time.
6054  */
6055 void sctp_sock_rfree(struct sk_buff *skb)
6056 {
6057 	struct sock *sk = skb->sk;
6058 	struct sctp_ulpevent *event = sctp_skb2event(skb);
6059 
6060 	atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
6061 
6062 	/*
6063 	 * Mimic the behavior of sock_rfree
6064 	 */
6065 	sk_mem_uncharge(sk, event->rmem_len);
6066 }
6067 
6068 
6069 /* Helper function to wait for space in the sndbuf.  */
6070 static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
6071 				size_t msg_len)
6072 {
6073 	struct sock *sk = asoc->base.sk;
6074 	int err = 0;
6075 	long current_timeo = *timeo_p;
6076 	DEFINE_WAIT(wait);
6077 
6078 	SCTP_DEBUG_PRINTK("wait_for_sndbuf: asoc=%p, timeo=%ld, msg_len=%zu\n",
6079 			  asoc, (long)(*timeo_p), msg_len);
6080 
6081 	/* Increment the association's refcnt.  */
6082 	sctp_association_hold(asoc);
6083 
6084 	/* Wait on the association specific sndbuf space. */
6085 	for (;;) {
6086 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6087 					  TASK_INTERRUPTIBLE);
6088 		if (!*timeo_p)
6089 			goto do_nonblock;
6090 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6091 		    asoc->base.dead)
6092 			goto do_error;
6093 		if (signal_pending(current))
6094 			goto do_interrupted;
6095 		if (msg_len <= sctp_wspace(asoc))
6096 			break;
6097 
6098 		/* Let another process have a go.  Since we are going
6099 		 * to sleep anyway.
6100 		 */
6101 		sctp_release_sock(sk);
6102 		current_timeo = schedule_timeout(current_timeo);
6103 		BUG_ON(sk != asoc->base.sk);
6104 		sctp_lock_sock(sk);
6105 
6106 		*timeo_p = current_timeo;
6107 	}
6108 
6109 out:
6110 	finish_wait(&asoc->wait, &wait);
6111 
6112 	/* Release the association's refcnt.  */
6113 	sctp_association_put(asoc);
6114 
6115 	return err;
6116 
6117 do_error:
6118 	err = -EPIPE;
6119 	goto out;
6120 
6121 do_interrupted:
6122 	err = sock_intr_errno(*timeo_p);
6123 	goto out;
6124 
6125 do_nonblock:
6126 	err = -EAGAIN;
6127 	goto out;
6128 }
6129 
6130 /* If socket sndbuf has changed, wake up all per association waiters.  */
6131 void sctp_write_space(struct sock *sk)
6132 {
6133 	struct sctp_association *asoc;
6134 	struct list_head *pos;
6135 
6136 	/* Wake up the tasks in each wait queue.  */
6137 	list_for_each(pos, &((sctp_sk(sk))->ep->asocs)) {
6138 		asoc = list_entry(pos, struct sctp_association, asocs);
6139 		__sctp_write_space(asoc);
6140 	}
6141 }
6142 
6143 /* Is there any sndbuf space available on the socket?
6144  *
6145  * Note that sk_wmem_alloc is the sum of the send buffers on all of the
6146  * associations on the same socket.  For a UDP-style socket with
6147  * multiple associations, it is possible for it to be "unwriteable"
6148  * prematurely.  I assume that this is acceptable because
6149  * a premature "unwriteable" is better than an accidental "writeable" which
6150  * would cause an unwanted block under certain circumstances.  For the 1-1
6151  * UDP-style sockets or TCP-style sockets, this code should work.
6152  *  - Daisy
6153  */
6154 static int sctp_writeable(struct sock *sk)
6155 {
6156 	int amt = 0;
6157 
6158 	amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
6159 	if (amt < 0)
6160 		amt = 0;
6161 	return amt;
6162 }
6163 
6164 /* Wait for an association to go into ESTABLISHED state. If timeout is 0,
6165  * returns immediately with EINPROGRESS.
6166  */
6167 static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
6168 {
6169 	struct sock *sk = asoc->base.sk;
6170 	int err = 0;
6171 	long current_timeo = *timeo_p;
6172 	DEFINE_WAIT(wait);
6173 
6174 	SCTP_DEBUG_PRINTK("%s: asoc=%p, timeo=%ld\n", __FUNCTION__, asoc,
6175 			  (long)(*timeo_p));
6176 
6177 	/* Increment the association's refcnt.  */
6178 	sctp_association_hold(asoc);
6179 
6180 	for (;;) {
6181 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6182 					  TASK_INTERRUPTIBLE);
6183 		if (!*timeo_p)
6184 			goto do_nonblock;
6185 		if (sk->sk_shutdown & RCV_SHUTDOWN)
6186 			break;
6187 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6188 		    asoc->base.dead)
6189 			goto do_error;
6190 		if (signal_pending(current))
6191 			goto do_interrupted;
6192 
6193 		if (sctp_state(asoc, ESTABLISHED))
6194 			break;
6195 
6196 		/* Let another process have a go.  Since we are going
6197 		 * to sleep anyway.
6198 		 */
6199 		sctp_release_sock(sk);
6200 		current_timeo = schedule_timeout(current_timeo);
6201 		sctp_lock_sock(sk);
6202 
6203 		*timeo_p = current_timeo;
6204 	}
6205 
6206 out:
6207 	finish_wait(&asoc->wait, &wait);
6208 
6209 	/* Release the association's refcnt.  */
6210 	sctp_association_put(asoc);
6211 
6212 	return err;
6213 
6214 do_error:
6215 	if (asoc->init_err_counter + 1 > asoc->max_init_attempts)
6216 		err = -ETIMEDOUT;
6217 	else
6218 		err = -ECONNREFUSED;
6219 	goto out;
6220 
6221 do_interrupted:
6222 	err = sock_intr_errno(*timeo_p);
6223 	goto out;
6224 
6225 do_nonblock:
6226 	err = -EINPROGRESS;
6227 	goto out;
6228 }
6229 
6230 static int sctp_wait_for_accept(struct sock *sk, long timeo)
6231 {
6232 	struct sctp_endpoint *ep;
6233 	int err = 0;
6234 	DEFINE_WAIT(wait);
6235 
6236 	ep = sctp_sk(sk)->ep;
6237 
6238 
6239 	for (;;) {
6240 		prepare_to_wait_exclusive(sk->sk_sleep, &wait,
6241 					  TASK_INTERRUPTIBLE);
6242 
6243 		if (list_empty(&ep->asocs)) {
6244 			sctp_release_sock(sk);
6245 			timeo = schedule_timeout(timeo);
6246 			sctp_lock_sock(sk);
6247 		}
6248 
6249 		err = -EINVAL;
6250 		if (!sctp_sstate(sk, LISTENING))
6251 			break;
6252 
6253 		err = 0;
6254 		if (!list_empty(&ep->asocs))
6255 			break;
6256 
6257 		err = sock_intr_errno(timeo);
6258 		if (signal_pending(current))
6259 			break;
6260 
6261 		err = -EAGAIN;
6262 		if (!timeo)
6263 			break;
6264 	}
6265 
6266 	finish_wait(sk->sk_sleep, &wait);
6267 
6268 	return err;
6269 }
6270 
6271 static void sctp_wait_for_close(struct sock *sk, long timeout)
6272 {
6273 	DEFINE_WAIT(wait);
6274 
6275 	do {
6276 		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
6277 		if (list_empty(&sctp_sk(sk)->ep->asocs))
6278 			break;
6279 		sctp_release_sock(sk);
6280 		timeout = schedule_timeout(timeout);
6281 		sctp_lock_sock(sk);
6282 	} while (!signal_pending(current) && timeout);
6283 
6284 	finish_wait(sk->sk_sleep, &wait);
6285 }
6286 
6287 static void sctp_sock_rfree_frag(struct sk_buff *skb)
6288 {
6289 	struct sk_buff *frag;
6290 
6291 	if (!skb->data_len)
6292 		goto done;
6293 
6294 	/* Don't forget the fragments. */
6295 	for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next)
6296 		sctp_sock_rfree_frag(frag);
6297 
6298 done:
6299 	sctp_sock_rfree(skb);
6300 }
6301 
6302 static void sctp_skb_set_owner_r_frag(struct sk_buff *skb, struct sock *sk)
6303 {
6304 	struct sk_buff *frag;
6305 
6306 	if (!skb->data_len)
6307 		goto done;
6308 
6309 	/* Don't forget the fragments. */
6310 	for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next)
6311 		sctp_skb_set_owner_r_frag(frag, sk);
6312 
6313 done:
6314 	sctp_skb_set_owner_r(skb, sk);
6315 }
6316 
6317 /* Populate the fields of the newsk from the oldsk and migrate the assoc
6318  * and its messages to the newsk.
6319  */
6320 static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
6321 			      struct sctp_association *assoc,
6322 			      sctp_socket_type_t type)
6323 {
6324 	struct sctp_sock *oldsp = sctp_sk(oldsk);
6325 	struct sctp_sock *newsp = sctp_sk(newsk);
6326 	struct sctp_bind_bucket *pp; /* hash list port iterator */
6327 	struct sctp_endpoint *newep = newsp->ep;
6328 	struct sk_buff *skb, *tmp;
6329 	struct sctp_ulpevent *event;
6330 	struct sctp_bind_hashbucket *head;
6331 
6332 	/* Migrate socket buffer sizes and all the socket level options to the
6333 	 * new socket.
6334 	 */
6335 	newsk->sk_sndbuf = oldsk->sk_sndbuf;
6336 	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
6337 	/* Brute force copy old sctp opt. */
6338 	inet_sk_copy_descendant(newsk, oldsk);
6339 
6340 	/* Restore the ep value that was overwritten with the above structure
6341 	 * copy.
6342 	 */
6343 	newsp->ep = newep;
6344 	newsp->hmac = NULL;
6345 
6346 	/* Hook this new socket in to the bind_hash list. */
6347 	head = &sctp_port_hashtable[sctp_phashfn(inet_sk(oldsk)->num)];
6348 	sctp_local_bh_disable();
6349 	sctp_spin_lock(&head->lock);
6350 	pp = sctp_sk(oldsk)->bind_hash;
6351 	sk_add_bind_node(newsk, &pp->owner);
6352 	sctp_sk(newsk)->bind_hash = pp;
6353 	inet_sk(newsk)->num = inet_sk(oldsk)->num;
6354 	sctp_spin_unlock(&head->lock);
6355 	sctp_local_bh_enable();
6356 
6357 	/* Copy the bind_addr list from the original endpoint to the new
6358 	 * endpoint so that we can handle restarts properly
6359 	 */
6360 	sctp_bind_addr_dup(&newsp->ep->base.bind_addr,
6361 				&oldsp->ep->base.bind_addr, GFP_KERNEL);
6362 
6363 	/* Move any messages in the old socket's receive queue that are for the
6364 	 * peeled off association to the new socket's receive queue.
6365 	 */
6366 	sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
6367 		event = sctp_skb2event(skb);
6368 		if (event->asoc == assoc) {
6369 			sctp_sock_rfree_frag(skb);
6370 			__skb_unlink(skb, &oldsk->sk_receive_queue);
6371 			__skb_queue_tail(&newsk->sk_receive_queue, skb);
6372 			sctp_skb_set_owner_r_frag(skb, newsk);
6373 		}
6374 	}
6375 
6376 	/* Clean up any messages pending delivery due to partial
6377 	 * delivery.   Three cases:
6378 	 * 1) No partial deliver;  no work.
6379 	 * 2) Peeling off partial delivery; keep pd_lobby in new pd_lobby.
6380 	 * 3) Peeling off non-partial delivery; move pd_lobby to receive_queue.
6381 	 */
6382 	skb_queue_head_init(&newsp->pd_lobby);
6383 	atomic_set(&sctp_sk(newsk)->pd_mode, assoc->ulpq.pd_mode);
6384 
6385 	if (atomic_read(&sctp_sk(oldsk)->pd_mode)) {
6386 		struct sk_buff_head *queue;
6387 
6388 		/* Decide which queue to move pd_lobby skbs to. */
6389 		if (assoc->ulpq.pd_mode) {
6390 			queue = &newsp->pd_lobby;
6391 		} else
6392 			queue = &newsk->sk_receive_queue;
6393 
6394 		/* Walk through the pd_lobby, looking for skbs that
6395 		 * need moved to the new socket.
6396 		 */
6397 		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
6398 			event = sctp_skb2event(skb);
6399 			if (event->asoc == assoc) {
6400 				sctp_sock_rfree_frag(skb);
6401 				__skb_unlink(skb, &oldsp->pd_lobby);
6402 				__skb_queue_tail(queue, skb);
6403 				sctp_skb_set_owner_r_frag(skb, newsk);
6404 			}
6405 		}
6406 
6407 		/* Clear up any skbs waiting for the partial
6408 		 * delivery to finish.
6409 		 */
6410 		if (assoc->ulpq.pd_mode)
6411 			sctp_clear_pd(oldsk, NULL);
6412 
6413 	}
6414 
6415 	sctp_skb_for_each(skb, &assoc->ulpq.reasm, tmp) {
6416 		sctp_sock_rfree_frag(skb);
6417 		sctp_skb_set_owner_r_frag(skb, newsk);
6418 	}
6419 
6420 	sctp_skb_for_each(skb, &assoc->ulpq.lobby, tmp) {
6421 		sctp_sock_rfree_frag(skb);
6422 		sctp_skb_set_owner_r_frag(skb, newsk);
6423 	}
6424 
6425 	/* Set the type of socket to indicate that it is peeled off from the
6426 	 * original UDP-style socket or created with the accept() call on a
6427 	 * TCP-style socket..
6428 	 */
6429 	newsp->type = type;
6430 
6431 	/* Mark the new socket "in-use" by the user so that any packets
6432 	 * that may arrive on the association after we've moved it are
6433 	 * queued to the backlog.  This prevents a potential race between
6434 	 * backlog processing on the old socket and new-packet processing
6435 	 * on the new socket.
6436 	 *
6437 	 * The caller has just allocated newsk so we can guarantee that other
6438 	 * paths won't try to lock it and then oldsk.
6439 	 */
6440 	lock_sock_nested(newsk, SINGLE_DEPTH_NESTING);
6441 	sctp_assoc_migrate(assoc, newsk);
6442 
6443 	/* If the association on the newsk is already closed before accept()
6444 	 * is called, set RCV_SHUTDOWN flag.
6445 	 */
6446 	if (sctp_state(assoc, CLOSED) && sctp_style(newsk, TCP))
6447 		newsk->sk_shutdown |= RCV_SHUTDOWN;
6448 
6449 	newsk->sk_state = SCTP_SS_ESTABLISHED;
6450 	sctp_release_sock(newsk);
6451 }
6452 
6453 
6454 DEFINE_PROTO_INUSE(sctp)
6455 
6456 /* This proto struct describes the ULP interface for SCTP.  */
6457 struct proto sctp_prot = {
6458 	.name        =	"SCTP",
6459 	.owner       =	THIS_MODULE,
6460 	.close       =	sctp_close,
6461 	.connect     =	sctp_connect,
6462 	.disconnect  =	sctp_disconnect,
6463 	.accept      =	sctp_accept,
6464 	.ioctl       =	sctp_ioctl,
6465 	.init        =	sctp_init_sock,
6466 	.destroy     =	sctp_destroy_sock,
6467 	.shutdown    =	sctp_shutdown,
6468 	.setsockopt  =	sctp_setsockopt,
6469 	.getsockopt  =	sctp_getsockopt,
6470 	.sendmsg     =	sctp_sendmsg,
6471 	.recvmsg     =	sctp_recvmsg,
6472 	.bind        =	sctp_bind,
6473 	.backlog_rcv =	sctp_backlog_rcv,
6474 	.hash        =	sctp_hash,
6475 	.unhash      =	sctp_unhash,
6476 	.get_port    =	sctp_get_port,
6477 	.obj_size    =  sizeof(struct sctp_sock),
6478 	.sysctl_mem  =  sysctl_sctp_mem,
6479 	.sysctl_rmem =  sysctl_sctp_rmem,
6480 	.sysctl_wmem =  sysctl_sctp_wmem,
6481 	.memory_pressure = &sctp_memory_pressure,
6482 	.enter_memory_pressure = sctp_enter_memory_pressure,
6483 	.memory_allocated = &sctp_memory_allocated,
6484 	REF_PROTO_INUSE(sctp)
6485 };
6486 
6487 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6488 DEFINE_PROTO_INUSE(sctpv6)
6489 
6490 struct proto sctpv6_prot = {
6491 	.name		= "SCTPv6",
6492 	.owner		= THIS_MODULE,
6493 	.close		= sctp_close,
6494 	.connect	= sctp_connect,
6495 	.disconnect	= sctp_disconnect,
6496 	.accept		= sctp_accept,
6497 	.ioctl		= sctp_ioctl,
6498 	.init		= sctp_init_sock,
6499 	.destroy	= sctp_destroy_sock,
6500 	.shutdown	= sctp_shutdown,
6501 	.setsockopt	= sctp_setsockopt,
6502 	.getsockopt	= sctp_getsockopt,
6503 	.sendmsg	= sctp_sendmsg,
6504 	.recvmsg	= sctp_recvmsg,
6505 	.bind		= sctp_bind,
6506 	.backlog_rcv	= sctp_backlog_rcv,
6507 	.hash		= sctp_hash,
6508 	.unhash		= sctp_unhash,
6509 	.get_port	= sctp_get_port,
6510 	.obj_size	= sizeof(struct sctp6_sock),
6511 	.sysctl_mem	= sysctl_sctp_mem,
6512 	.sysctl_rmem	= sysctl_sctp_rmem,
6513 	.sysctl_wmem	= sysctl_sctp_wmem,
6514 	.memory_pressure = &sctp_memory_pressure,
6515 	.enter_memory_pressure = sctp_enter_memory_pressure,
6516 	.memory_allocated = &sctp_memory_allocated,
6517 	REF_PROTO_INUSE(sctpv6)
6518 };
6519 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
6520