xref: /linux/net/sctp/socket.c (revision eb2bce7f5e7ac1ca6da434461217fadf3c688d2c)
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 
112 /* Get the sndbuf space available at the time on the association.  */
113 static inline int sctp_wspace(struct sctp_association *asoc)
114 {
115 	struct sock *sk = asoc->base.sk;
116 	int amt = 0;
117 
118 	if (asoc->ep->sndbuf_policy) {
119 		/* make sure that no association uses more than sk_sndbuf */
120 		amt = sk->sk_sndbuf - asoc->sndbuf_used;
121 	} else {
122 		/* do socket level accounting */
123 		amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
124 	}
125 
126 	if (amt < 0)
127 		amt = 0;
128 
129 	return amt;
130 }
131 
132 /* Increment the used sndbuf space count of the corresponding association by
133  * the size of the outgoing data chunk.
134  * Also, set the skb destructor for sndbuf accounting later.
135  *
136  * Since it is always 1-1 between chunk and skb, and also a new skb is always
137  * allocated for chunk bundling in sctp_packet_transmit(), we can use the
138  * destructor in the data chunk skb for the purpose of the sndbuf space
139  * tracking.
140  */
141 static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
142 {
143 	struct sctp_association *asoc = chunk->asoc;
144 	struct sock *sk = asoc->base.sk;
145 
146 	/* The sndbuf space is tracked per association.  */
147 	sctp_association_hold(asoc);
148 
149 	skb_set_owner_w(chunk->skb, sk);
150 
151 	chunk->skb->destructor = sctp_wfree;
152 	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
153 	*((struct sctp_chunk **)(chunk->skb->cb)) = chunk;
154 
155 	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
156 				sizeof(struct sk_buff) +
157 				sizeof(struct sctp_chunk);
158 
159 	atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
160 }
161 
162 /* Verify that this is a valid address. */
163 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
164 				   int len)
165 {
166 	struct sctp_af *af;
167 
168 	/* Verify basic sockaddr. */
169 	af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
170 	if (!af)
171 		return -EINVAL;
172 
173 	/* Is this a valid SCTP address?  */
174 	if (!af->addr_valid(addr, sctp_sk(sk), NULL))
175 		return -EINVAL;
176 
177 	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
178 		return -EINVAL;
179 
180 	return 0;
181 }
182 
183 /* Look up the association by its id.  If this is not a UDP-style
184  * socket, the ID field is always ignored.
185  */
186 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
187 {
188 	struct sctp_association *asoc = NULL;
189 
190 	/* If this is not a UDP-style socket, assoc id should be ignored. */
191 	if (!sctp_style(sk, UDP)) {
192 		/* Return NULL if the socket state is not ESTABLISHED. It
193 		 * could be a TCP-style listening socket or a socket which
194 		 * hasn't yet called connect() to establish an association.
195 		 */
196 		if (!sctp_sstate(sk, ESTABLISHED))
197 			return NULL;
198 
199 		/* Get the first and the only association from the list. */
200 		if (!list_empty(&sctp_sk(sk)->ep->asocs))
201 			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
202 					  struct sctp_association, asocs);
203 		return asoc;
204 	}
205 
206 	/* Otherwise this is a UDP-style socket. */
207 	if (!id || (id == (sctp_assoc_t)-1))
208 		return NULL;
209 
210 	spin_lock_bh(&sctp_assocs_id_lock);
211 	asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
212 	spin_unlock_bh(&sctp_assocs_id_lock);
213 
214 	if (!asoc || (asoc->base.sk != sk) || asoc->base.dead)
215 		return NULL;
216 
217 	return asoc;
218 }
219 
220 /* Look up the transport from an address and an assoc id. If both address and
221  * id are specified, the associations matching the address and the id should be
222  * the same.
223  */
224 static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
225 					      struct sockaddr_storage *addr,
226 					      sctp_assoc_t id)
227 {
228 	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
229 	struct sctp_transport *transport;
230 	union sctp_addr *laddr = (union sctp_addr *)addr;
231 
232 	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
233 					       laddr,
234 					       &transport);
235 
236 	if (!addr_asoc)
237 		return NULL;
238 
239 	id_asoc = sctp_id2assoc(sk, id);
240 	if (id_asoc && (id_asoc != addr_asoc))
241 		return NULL;
242 
243 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
244 						(union sctp_addr *)addr);
245 
246 	return transport;
247 }
248 
249 /* API 3.1.2 bind() - UDP Style Syntax
250  * The syntax of bind() is,
251  *
252  *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
253  *
254  *   sd      - the socket descriptor returned by socket().
255  *   addr    - the address structure (struct sockaddr_in or struct
256  *             sockaddr_in6 [RFC 2553]),
257  *   addr_len - the size of the address structure.
258  */
259 SCTP_STATIC int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
260 {
261 	int retval = 0;
262 
263 	sctp_lock_sock(sk);
264 
265 	SCTP_DEBUG_PRINTK("sctp_bind(sk: %p, addr: %p, addr_len: %d)\n",
266 			  sk, addr, addr_len);
267 
268 	/* Disallow binding twice. */
269 	if (!sctp_sk(sk)->ep->base.bind_addr.port)
270 		retval = sctp_do_bind(sk, (union sctp_addr *)addr,
271 				      addr_len);
272 	else
273 		retval = -EINVAL;
274 
275 	sctp_release_sock(sk);
276 
277 	return retval;
278 }
279 
280 static long sctp_get_port_local(struct sock *, union sctp_addr *);
281 
282 /* Verify this is a valid sockaddr. */
283 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
284 					union sctp_addr *addr, int len)
285 {
286 	struct sctp_af *af;
287 
288 	/* Check minimum size.  */
289 	if (len < sizeof (struct sockaddr))
290 		return NULL;
291 
292 	/* Does this PF support this AF? */
293 	if (!opt->pf->af_supported(addr->sa.sa_family, opt))
294 		return NULL;
295 
296 	/* If we get this far, af is valid. */
297 	af = sctp_get_af_specific(addr->sa.sa_family);
298 
299 	if (len < af->sockaddr_len)
300 		return NULL;
301 
302 	return af;
303 }
304 
305 /* Bind a local address either to an endpoint or to an association.  */
306 SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
307 {
308 	struct sctp_sock *sp = sctp_sk(sk);
309 	struct sctp_endpoint *ep = sp->ep;
310 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
311 	struct sctp_af *af;
312 	unsigned short snum;
313 	int ret = 0;
314 
315 	/* Common sockaddr verification. */
316 	af = sctp_sockaddr_af(sp, addr, len);
317 	if (!af) {
318 		SCTP_DEBUG_PRINTK("sctp_do_bind(sk: %p, newaddr: %p, len: %d) EINVAL\n",
319 				  sk, addr, len);
320 		return -EINVAL;
321 	}
322 
323 	snum = ntohs(addr->v4.sin_port);
324 
325 	SCTP_DEBUG_PRINTK_IPADDR("sctp_do_bind(sk: %p, new addr: ",
326 				 ", port: %d, new port: %d, len: %d)\n",
327 				 sk,
328 				 addr,
329 				 bp->port, snum,
330 				 len);
331 
332 	/* PF specific bind() address verification. */
333 	if (!sp->pf->bind_verify(sp, addr))
334 		return -EADDRNOTAVAIL;
335 
336 	/* We must either be unbound, or bind to the same port.  */
337 	if (bp->port && (snum != bp->port)) {
338 		SCTP_DEBUG_PRINTK("sctp_do_bind:"
339 				  " New port %d does not match existing port "
340 				  "%d.\n", snum, bp->port);
341 		return -EINVAL;
342 	}
343 
344 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
345 		return -EACCES;
346 
347 	/* Make sure we are allowed to bind here.
348 	 * The function sctp_get_port_local() does duplicate address
349 	 * detection.
350 	 */
351 	if ((ret = sctp_get_port_local(sk, addr))) {
352 		if (ret == (long) sk) {
353 			/* This endpoint has a conflicting address. */
354 			return -EINVAL;
355 		} else {
356 			return -EADDRINUSE;
357 		}
358 	}
359 
360 	/* Refresh ephemeral port.  */
361 	if (!bp->port)
362 		bp->port = inet_sk(sk)->num;
363 
364 	/* Add the address to the bind address list.  */
365 	sctp_local_bh_disable();
366 	sctp_write_lock(&ep->base.addr_lock);
367 
368 	/* Use GFP_ATOMIC since BHs are disabled.  */
369 	ret = sctp_add_bind_addr(bp, addr, 1, GFP_ATOMIC);
370 	sctp_write_unlock(&ep->base.addr_lock);
371 	sctp_local_bh_enable();
372 
373 	/* Copy back into socket for getsockname() use. */
374 	if (!ret) {
375 		inet_sk(sk)->sport = htons(inet_sk(sk)->num);
376 		af->to_sk_saddr(addr, sk);
377 	}
378 
379 	return ret;
380 }
381 
382  /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
383  *
384  * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
385  * at any one time.  If a sender, after sending an ASCONF chunk, decides
386  * it needs to transfer another ASCONF Chunk, it MUST wait until the
387  * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
388  * subsequent ASCONF. Note this restriction binds each side, so at any
389  * time two ASCONF may be in-transit on any given association (one sent
390  * from each endpoint).
391  */
392 static int sctp_send_asconf(struct sctp_association *asoc,
393 			    struct sctp_chunk *chunk)
394 {
395 	int		retval = 0;
396 
397 	/* If there is an outstanding ASCONF chunk, queue it for later
398 	 * transmission.
399 	 */
400 	if (asoc->addip_last_asconf) {
401 		list_add_tail(&chunk->list, &asoc->addip_chunk_list);
402 		goto out;
403 	}
404 
405 	/* Hold the chunk until an ASCONF_ACK is received. */
406 	sctp_chunk_hold(chunk);
407 	retval = sctp_primitive_ASCONF(asoc, chunk);
408 	if (retval)
409 		sctp_chunk_free(chunk);
410 	else
411 		asoc->addip_last_asconf = chunk;
412 
413 out:
414 	return retval;
415 }
416 
417 /* Add a list of addresses as bind addresses to local endpoint or
418  * association.
419  *
420  * Basically run through each address specified in the addrs/addrcnt
421  * array/length pair, determine if it is IPv6 or IPv4 and call
422  * sctp_do_bind() on it.
423  *
424  * If any of them fails, then the operation will be reversed and the
425  * ones that were added will be removed.
426  *
427  * Only sctp_setsockopt_bindx() is supposed to call this function.
428  */
429 int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
430 {
431 	int cnt;
432 	int retval = 0;
433 	void *addr_buf;
434 	struct sockaddr *sa_addr;
435 	struct sctp_af *af;
436 
437 	SCTP_DEBUG_PRINTK("sctp_bindx_add (sk: %p, addrs: %p, addrcnt: %d)\n",
438 			  sk, addrs, addrcnt);
439 
440 	addr_buf = addrs;
441 	for (cnt = 0; cnt < addrcnt; cnt++) {
442 		/* The list may contain either IPv4 or IPv6 address;
443 		 * determine the address length for walking thru the list.
444 		 */
445 		sa_addr = (struct sockaddr *)addr_buf;
446 		af = sctp_get_af_specific(sa_addr->sa_family);
447 		if (!af) {
448 			retval = -EINVAL;
449 			goto err_bindx_add;
450 		}
451 
452 		retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
453 				      af->sockaddr_len);
454 
455 		addr_buf += af->sockaddr_len;
456 
457 err_bindx_add:
458 		if (retval < 0) {
459 			/* Failed. Cleanup the ones that have been added */
460 			if (cnt > 0)
461 				sctp_bindx_rem(sk, addrs, cnt);
462 			return retval;
463 		}
464 	}
465 
466 	return retval;
467 }
468 
469 /* Send an ASCONF chunk with Add IP address parameters to all the peers of the
470  * associations that are part of the endpoint indicating that a list of local
471  * addresses are added to the endpoint.
472  *
473  * If any of the addresses is already in the bind address list of the
474  * association, we do not send the chunk for that association.  But it will not
475  * affect other associations.
476  *
477  * Only sctp_setsockopt_bindx() is supposed to call this function.
478  */
479 static int sctp_send_asconf_add_ip(struct sock		*sk,
480 				   struct sockaddr	*addrs,
481 				   int 			addrcnt)
482 {
483 	struct sctp_sock		*sp;
484 	struct sctp_endpoint		*ep;
485 	struct sctp_association		*asoc;
486 	struct sctp_bind_addr		*bp;
487 	struct sctp_chunk		*chunk;
488 	struct sctp_sockaddr_entry	*laddr;
489 	union sctp_addr			*addr;
490 	union sctp_addr			saveaddr;
491 	void				*addr_buf;
492 	struct sctp_af			*af;
493 	struct list_head		*pos;
494 	struct list_head		*p;
495 	int 				i;
496 	int 				retval = 0;
497 
498 	if (!sctp_addip_enable)
499 		return retval;
500 
501 	sp = sctp_sk(sk);
502 	ep = sp->ep;
503 
504 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
505 			  __FUNCTION__, sk, addrs, addrcnt);
506 
507 	list_for_each(pos, &ep->asocs) {
508 		asoc = list_entry(pos, struct sctp_association, asocs);
509 
510 		if (!asoc->peer.asconf_capable)
511 			continue;
512 
513 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
514 			continue;
515 
516 		if (!sctp_state(asoc, ESTABLISHED))
517 			continue;
518 
519 		/* Check if any address in the packed array of addresses is
520 		 * in the bind address list of the association. If so,
521 		 * do not send the asconf chunk to its peer, but continue with
522 		 * other associations.
523 		 */
524 		addr_buf = addrs;
525 		for (i = 0; i < addrcnt; i++) {
526 			addr = (union sctp_addr *)addr_buf;
527 			af = sctp_get_af_specific(addr->v4.sin_family);
528 			if (!af) {
529 				retval = -EINVAL;
530 				goto out;
531 			}
532 
533 			if (sctp_assoc_lookup_laddr(asoc, addr))
534 				break;
535 
536 			addr_buf += af->sockaddr_len;
537 		}
538 		if (i < addrcnt)
539 			continue;
540 
541 		/* Use the first address in bind addr list of association as
542 		 * Address Parameter of ASCONF CHUNK.
543 		 */
544 		sctp_read_lock(&asoc->base.addr_lock);
545 		bp = &asoc->base.bind_addr;
546 		p = bp->address_list.next;
547 		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
548 		sctp_read_unlock(&asoc->base.addr_lock);
549 
550 		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
551 						   addrcnt, SCTP_PARAM_ADD_IP);
552 		if (!chunk) {
553 			retval = -ENOMEM;
554 			goto out;
555 		}
556 
557 		retval = sctp_send_asconf(asoc, chunk);
558 		if (retval)
559 			goto out;
560 
561 		/* Add the new addresses to the bind address list with
562 		 * use_as_src set to 0.
563 		 */
564 		sctp_local_bh_disable();
565 		sctp_write_lock(&asoc->base.addr_lock);
566 		addr_buf = addrs;
567 		for (i = 0; i < addrcnt; i++) {
568 			addr = (union sctp_addr *)addr_buf;
569 			af = sctp_get_af_specific(addr->v4.sin_family);
570 			memcpy(&saveaddr, addr, af->sockaddr_len);
571 			retval = sctp_add_bind_addr(bp, &saveaddr, 0,
572 						    GFP_ATOMIC);
573 			addr_buf += af->sockaddr_len;
574 		}
575 		sctp_write_unlock(&asoc->base.addr_lock);
576 		sctp_local_bh_enable();
577 	}
578 
579 out:
580 	return retval;
581 }
582 
583 /* Remove a list of addresses from bind addresses list.  Do not remove the
584  * last address.
585  *
586  * Basically run through each address specified in the addrs/addrcnt
587  * array/length pair, determine if it is IPv6 or IPv4 and call
588  * sctp_del_bind() on it.
589  *
590  * If any of them fails, then the operation will be reversed and the
591  * ones that were removed will be added back.
592  *
593  * At least one address has to be left; if only one address is
594  * available, the operation will return -EBUSY.
595  *
596  * Only sctp_setsockopt_bindx() is supposed to call this function.
597  */
598 int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
599 {
600 	struct sctp_sock *sp = sctp_sk(sk);
601 	struct sctp_endpoint *ep = sp->ep;
602 	int cnt;
603 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
604 	int retval = 0;
605 	void *addr_buf;
606 	union sctp_addr *sa_addr;
607 	struct sctp_af *af;
608 
609 	SCTP_DEBUG_PRINTK("sctp_bindx_rem (sk: %p, addrs: %p, addrcnt: %d)\n",
610 			  sk, addrs, addrcnt);
611 
612 	addr_buf = addrs;
613 	for (cnt = 0; cnt < addrcnt; cnt++) {
614 		/* If the bind address list is empty or if there is only one
615 		 * bind address, there is nothing more to be removed (we need
616 		 * at least one address here).
617 		 */
618 		if (list_empty(&bp->address_list) ||
619 		    (sctp_list_single_entry(&bp->address_list))) {
620 			retval = -EBUSY;
621 			goto err_bindx_rem;
622 		}
623 
624 		sa_addr = (union sctp_addr *)addr_buf;
625 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
626 		if (!af) {
627 			retval = -EINVAL;
628 			goto err_bindx_rem;
629 		}
630 
631 		if (!af->addr_valid(sa_addr, sp, NULL)) {
632 			retval = -EADDRNOTAVAIL;
633 			goto err_bindx_rem;
634 		}
635 
636 		if (sa_addr->v4.sin_port != htons(bp->port)) {
637 			retval = -EINVAL;
638 			goto err_bindx_rem;
639 		}
640 
641 		/* FIXME - There is probably a need to check if sk->sk_saddr and
642 		 * sk->sk_rcv_addr are currently set to one of the addresses to
643 		 * be removed. This is something which needs to be looked into
644 		 * when we are fixing the outstanding issues with multi-homing
645 		 * socket routing and failover schemes. Refer to comments in
646 		 * sctp_do_bind(). -daisy
647 		 */
648 		sctp_local_bh_disable();
649 		sctp_write_lock(&ep->base.addr_lock);
650 
651 		retval = sctp_del_bind_addr(bp, sa_addr);
652 
653 		sctp_write_unlock(&ep->base.addr_lock);
654 		sctp_local_bh_enable();
655 
656 		addr_buf += af->sockaddr_len;
657 err_bindx_rem:
658 		if (retval < 0) {
659 			/* Failed. Add the ones that has been removed back */
660 			if (cnt > 0)
661 				sctp_bindx_add(sk, addrs, cnt);
662 			return retval;
663 		}
664 	}
665 
666 	return retval;
667 }
668 
669 /* Send an ASCONF chunk with Delete IP address parameters to all the peers of
670  * the associations that are part of the endpoint indicating that a list of
671  * local addresses are removed from the endpoint.
672  *
673  * If any of the addresses is already in the bind address list of the
674  * association, we do not send the chunk for that association.  But it will not
675  * affect other associations.
676  *
677  * Only sctp_setsockopt_bindx() is supposed to call this function.
678  */
679 static int sctp_send_asconf_del_ip(struct sock		*sk,
680 				   struct sockaddr	*addrs,
681 				   int			addrcnt)
682 {
683 	struct sctp_sock	*sp;
684 	struct sctp_endpoint	*ep;
685 	struct sctp_association	*asoc;
686 	struct sctp_transport	*transport;
687 	struct sctp_bind_addr	*bp;
688 	struct sctp_chunk	*chunk;
689 	union sctp_addr		*laddr;
690 	void			*addr_buf;
691 	struct sctp_af		*af;
692 	struct list_head	*pos, *pos1;
693 	struct sctp_sockaddr_entry *saddr;
694 	int 			i;
695 	int 			retval = 0;
696 
697 	if (!sctp_addip_enable)
698 		return retval;
699 
700 	sp = sctp_sk(sk);
701 	ep = sp->ep;
702 
703 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
704 			  __FUNCTION__, sk, addrs, addrcnt);
705 
706 	list_for_each(pos, &ep->asocs) {
707 		asoc = list_entry(pos, struct sctp_association, asocs);
708 
709 		if (!asoc->peer.asconf_capable)
710 			continue;
711 
712 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
713 			continue;
714 
715 		if (!sctp_state(asoc, ESTABLISHED))
716 			continue;
717 
718 		/* Check if any address in the packed array of addresses is
719 		 * not present in the bind address list of the association.
720 		 * If so, do not send the asconf chunk to its peer, but
721 		 * continue with other associations.
722 		 */
723 		addr_buf = addrs;
724 		for (i = 0; i < addrcnt; i++) {
725 			laddr = (union sctp_addr *)addr_buf;
726 			af = sctp_get_af_specific(laddr->v4.sin_family);
727 			if (!af) {
728 				retval = -EINVAL;
729 				goto out;
730 			}
731 
732 			if (!sctp_assoc_lookup_laddr(asoc, laddr))
733 				break;
734 
735 			addr_buf += af->sockaddr_len;
736 		}
737 		if (i < addrcnt)
738 			continue;
739 
740 		/* Find one address in the association's bind address list
741 		 * that is not in the packed array of addresses. This is to
742 		 * make sure that we do not delete all the addresses in the
743 		 * association.
744 		 */
745 		sctp_read_lock(&asoc->base.addr_lock);
746 		bp = &asoc->base.bind_addr;
747 		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
748 					       addrcnt, sp);
749 		sctp_read_unlock(&asoc->base.addr_lock);
750 		if (!laddr)
751 			continue;
752 
753 		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
754 						   SCTP_PARAM_DEL_IP);
755 		if (!chunk) {
756 			retval = -ENOMEM;
757 			goto out;
758 		}
759 
760 		/* Reset use_as_src flag for the addresses in the bind address
761 		 * list that are to be deleted.
762 		 */
763 		sctp_local_bh_disable();
764 		sctp_write_lock(&asoc->base.addr_lock);
765 		addr_buf = addrs;
766 		for (i = 0; i < addrcnt; i++) {
767 			laddr = (union sctp_addr *)addr_buf;
768 			af = sctp_get_af_specific(laddr->v4.sin_family);
769 			list_for_each(pos1, &bp->address_list) {
770 				saddr = list_entry(pos1,
771 						   struct sctp_sockaddr_entry,
772 						   list);
773 				if (sctp_cmp_addr_exact(&saddr->a, laddr))
774 					saddr->use_as_src = 0;
775 			}
776 			addr_buf += af->sockaddr_len;
777 		}
778 		sctp_write_unlock(&asoc->base.addr_lock);
779 		sctp_local_bh_enable();
780 
781 		/* Update the route and saddr entries for all the transports
782 		 * as some of the addresses in the bind address list are
783 		 * about to be deleted and cannot be used as source addresses.
784 		 */
785 		list_for_each(pos1, &asoc->peer.transport_addr_list) {
786 			transport = list_entry(pos1, struct sctp_transport,
787 					       transports);
788 			dst_release(transport->dst);
789 			sctp_transport_route(transport, NULL,
790 					     sctp_sk(asoc->base.sk));
791 		}
792 
793 		retval = sctp_send_asconf(asoc, chunk);
794 	}
795 out:
796 	return retval;
797 }
798 
799 /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
800  *
801  * API 8.1
802  * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt,
803  *                int flags);
804  *
805  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
806  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
807  * or IPv6 addresses.
808  *
809  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
810  * Section 3.1.2 for this usage.
811  *
812  * addrs is a pointer to an array of one or more socket addresses. Each
813  * address is contained in its appropriate structure (i.e. struct
814  * sockaddr_in or struct sockaddr_in6) the family of the address type
815  * must be used to distinguish the address length (note that this
816  * representation is termed a "packed array" of addresses). The caller
817  * specifies the number of addresses in the array with addrcnt.
818  *
819  * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns
820  * -1, and sets errno to the appropriate error code.
821  *
822  * For SCTP, the port given in each socket address must be the same, or
823  * sctp_bindx() will fail, setting errno to EINVAL.
824  *
825  * The flags parameter is formed from the bitwise OR of zero or more of
826  * the following currently defined flags:
827  *
828  * SCTP_BINDX_ADD_ADDR
829  *
830  * SCTP_BINDX_REM_ADDR
831  *
832  * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
833  * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given
834  * addresses from the association. The two flags are mutually exclusive;
835  * if both are given, sctp_bindx() will fail with EINVAL. A caller may
836  * not remove all addresses from an association; sctp_bindx() will
837  * reject such an attempt with EINVAL.
838  *
839  * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
840  * additional addresses with an endpoint after calling bind().  Or use
841  * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
842  * socket is associated with so that no new association accepted will be
843  * associated with those addresses. If the endpoint supports dynamic
844  * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
845  * endpoint to send the appropriate message to the peer to change the
846  * peers address lists.
847  *
848  * Adding and removing addresses from a connected association is
849  * optional functionality. Implementations that do not support this
850  * functionality should return EOPNOTSUPP.
851  *
852  * Basically do nothing but copying the addresses from user to kernel
853  * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
854  * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
855  * from userspace.
856  *
857  * We don't use copy_from_user() for optimization: we first do the
858  * sanity checks (buffer size -fast- and access check-healthy
859  * pointer); if all of those succeed, then we can alloc the memory
860  * (expensive operation) needed to copy the data to kernel. Then we do
861  * the copying without checking the user space area
862  * (__copy_from_user()).
863  *
864  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
865  * it.
866  *
867  * sk        The sk of the socket
868  * addrs     The pointer to the addresses in user land
869  * addrssize Size of the addrs buffer
870  * op        Operation to perform (add or remove, see the flags of
871  *           sctp_bindx)
872  *
873  * Returns 0 if ok, <0 errno code on error.
874  */
875 SCTP_STATIC int sctp_setsockopt_bindx(struct sock* sk,
876 				      struct sockaddr __user *addrs,
877 				      int addrs_size, int op)
878 {
879 	struct sockaddr *kaddrs;
880 	int err;
881 	int addrcnt = 0;
882 	int walk_size = 0;
883 	struct sockaddr *sa_addr;
884 	void *addr_buf;
885 	struct sctp_af *af;
886 
887 	SCTP_DEBUG_PRINTK("sctp_setsocktopt_bindx: sk %p addrs %p"
888 			  " addrs_size %d opt %d\n", sk, addrs, addrs_size, op);
889 
890 	if (unlikely(addrs_size <= 0))
891 		return -EINVAL;
892 
893 	/* Check the user passed a healthy pointer.  */
894 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
895 		return -EFAULT;
896 
897 	/* Alloc space for the address array in kernel memory.  */
898 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
899 	if (unlikely(!kaddrs))
900 		return -ENOMEM;
901 
902 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
903 		kfree(kaddrs);
904 		return -EFAULT;
905 	}
906 
907 	/* Walk through the addrs buffer and count the number of addresses. */
908 	addr_buf = kaddrs;
909 	while (walk_size < addrs_size) {
910 		sa_addr = (struct sockaddr *)addr_buf;
911 		af = sctp_get_af_specific(sa_addr->sa_family);
912 
913 		/* If the address family is not supported or if this address
914 		 * causes the address buffer to overflow return EINVAL.
915 		 */
916 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
917 			kfree(kaddrs);
918 			return -EINVAL;
919 		}
920 		addrcnt++;
921 		addr_buf += af->sockaddr_len;
922 		walk_size += af->sockaddr_len;
923 	}
924 
925 	/* Do the work. */
926 	switch (op) {
927 	case SCTP_BINDX_ADD_ADDR:
928 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
929 		if (err)
930 			goto out;
931 		err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
932 		break;
933 
934 	case SCTP_BINDX_REM_ADDR:
935 		err = sctp_bindx_rem(sk, kaddrs, addrcnt);
936 		if (err)
937 			goto out;
938 		err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
939 		break;
940 
941 	default:
942 		err = -EINVAL;
943 		break;
944 	}
945 
946 out:
947 	kfree(kaddrs);
948 
949 	return err;
950 }
951 
952 /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
953  *
954  * Common routine for handling connect() and sctp_connectx().
955  * Connect will come in with just a single address.
956  */
957 static int __sctp_connect(struct sock* sk,
958 			  struct sockaddr *kaddrs,
959 			  int addrs_size)
960 {
961 	struct sctp_sock *sp;
962 	struct sctp_endpoint *ep;
963 	struct sctp_association *asoc = NULL;
964 	struct sctp_association *asoc2;
965 	struct sctp_transport *transport;
966 	union sctp_addr to;
967 	struct sctp_af *af;
968 	sctp_scope_t scope;
969 	long timeo;
970 	int err = 0;
971 	int addrcnt = 0;
972 	int walk_size = 0;
973 	union sctp_addr *sa_addr;
974 	void *addr_buf;
975 	unsigned short port;
976 
977 	sp = sctp_sk(sk);
978 	ep = sp->ep;
979 
980 	/* connect() cannot be done on a socket that is already in ESTABLISHED
981 	 * state - UDP-style peeled off socket or a TCP-style socket that
982 	 * is already connected.
983 	 * It cannot be done even on a TCP-style listening socket.
984 	 */
985 	if (sctp_sstate(sk, ESTABLISHED) ||
986 	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
987 		err = -EISCONN;
988 		goto out_free;
989 	}
990 
991 	/* Walk through the addrs buffer and count the number of addresses. */
992 	addr_buf = kaddrs;
993 	while (walk_size < addrs_size) {
994 		sa_addr = (union sctp_addr *)addr_buf;
995 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
996 		port = ntohs(sa_addr->v4.sin_port);
997 
998 		/* If the address family is not supported or if this address
999 		 * causes the address buffer to overflow return EINVAL.
1000 		 */
1001 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1002 			err = -EINVAL;
1003 			goto out_free;
1004 		}
1005 
1006 		err = sctp_verify_addr(sk, sa_addr, af->sockaddr_len);
1007 		if (err)
1008 			goto out_free;
1009 
1010 		/* Make sure the destination port is correctly set
1011 		 * in all addresses.
1012 		 */
1013 		if (asoc && asoc->peer.port && asoc->peer.port != port)
1014 			goto out_free;
1015 
1016 		memcpy(&to, sa_addr, af->sockaddr_len);
1017 
1018 		/* Check if there already is a matching association on the
1019 		 * endpoint (other than the one created here).
1020 		 */
1021 		asoc2 = sctp_endpoint_lookup_assoc(ep, sa_addr, &transport);
1022 		if (asoc2 && asoc2 != asoc) {
1023 			if (asoc2->state >= SCTP_STATE_ESTABLISHED)
1024 				err = -EISCONN;
1025 			else
1026 				err = -EALREADY;
1027 			goto out_free;
1028 		}
1029 
1030 		/* If we could not find a matching association on the endpoint,
1031 		 * make sure that there is no peeled-off association matching
1032 		 * the peer address even on another socket.
1033 		 */
1034 		if (sctp_endpoint_is_peeled_off(ep, sa_addr)) {
1035 			err = -EADDRNOTAVAIL;
1036 			goto out_free;
1037 		}
1038 
1039 		if (!asoc) {
1040 			/* If a bind() or sctp_bindx() is not called prior to
1041 			 * an sctp_connectx() call, the system picks an
1042 			 * ephemeral port and will choose an address set
1043 			 * equivalent to binding with a wildcard address.
1044 			 */
1045 			if (!ep->base.bind_addr.port) {
1046 				if (sctp_autobind(sk)) {
1047 					err = -EAGAIN;
1048 					goto out_free;
1049 				}
1050 			} else {
1051 				/*
1052 				 * If an unprivileged user inherits a 1-many
1053 				 * style socket with open associations on a
1054 				 * privileged port, it MAY be permitted to
1055 				 * accept new associations, but it SHOULD NOT
1056 				 * be permitted to open new associations.
1057 				 */
1058 				if (ep->base.bind_addr.port < PROT_SOCK &&
1059 				    !capable(CAP_NET_BIND_SERVICE)) {
1060 					err = -EACCES;
1061 					goto out_free;
1062 				}
1063 			}
1064 
1065 			scope = sctp_scope(sa_addr);
1066 			asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1067 			if (!asoc) {
1068 				err = -ENOMEM;
1069 				goto out_free;
1070 			}
1071 		}
1072 
1073 		/* Prime the peer's transport structures.  */
1074 		transport = sctp_assoc_add_peer(asoc, sa_addr, GFP_KERNEL,
1075 						SCTP_UNKNOWN);
1076 		if (!transport) {
1077 			err = -ENOMEM;
1078 			goto out_free;
1079 		}
1080 
1081 		addrcnt++;
1082 		addr_buf += af->sockaddr_len;
1083 		walk_size += af->sockaddr_len;
1084 	}
1085 
1086 	err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
1087 	if (err < 0) {
1088 		goto out_free;
1089 	}
1090 
1091 	err = sctp_primitive_ASSOCIATE(asoc, NULL);
1092 	if (err < 0) {
1093 		goto out_free;
1094 	}
1095 
1096 	/* Initialize sk's dport and daddr for getpeername() */
1097 	inet_sk(sk)->dport = htons(asoc->peer.port);
1098 	af = sctp_get_af_specific(to.sa.sa_family);
1099 	af->to_sk_daddr(&to, sk);
1100 	sk->sk_err = 0;
1101 
1102 	timeo = sock_sndtimeo(sk, sk->sk_socket->file->f_flags & O_NONBLOCK);
1103 	err = sctp_wait_for_connect(asoc, &timeo);
1104 
1105 	/* Don't free association on exit. */
1106 	asoc = NULL;
1107 
1108 out_free:
1109 
1110 	SCTP_DEBUG_PRINTK("About to exit __sctp_connect() free asoc: %p"
1111 			  " kaddrs: %p err: %d\n",
1112 			  asoc, kaddrs, err);
1113 	if (asoc)
1114 		sctp_association_free(asoc);
1115 	return err;
1116 }
1117 
1118 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
1119  *
1120  * API 8.9
1121  * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt);
1122  *
1123  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
1124  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
1125  * or IPv6 addresses.
1126  *
1127  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
1128  * Section 3.1.2 for this usage.
1129  *
1130  * addrs is a pointer to an array of one or more socket addresses. Each
1131  * address is contained in its appropriate structure (i.e. struct
1132  * sockaddr_in or struct sockaddr_in6) the family of the address type
1133  * must be used to distengish the address length (note that this
1134  * representation is termed a "packed array" of addresses). The caller
1135  * specifies the number of addresses in the array with addrcnt.
1136  *
1137  * On success, sctp_connectx() returns 0. On failure, sctp_connectx() returns
1138  * -1, and sets errno to the appropriate error code.
1139  *
1140  * For SCTP, the port given in each socket address must be the same, or
1141  * sctp_connectx() will fail, setting errno to EINVAL.
1142  *
1143  * An application can use sctp_connectx to initiate an association with
1144  * an endpoint that is multi-homed.  Much like sctp_bindx() this call
1145  * allows a caller to specify multiple addresses at which a peer can be
1146  * reached.  The way the SCTP stack uses the list of addresses to set up
1147  * the association is implementation dependant.  This function only
1148  * specifies that the stack will try to make use of all the addresses in
1149  * the list when needed.
1150  *
1151  * Note that the list of addresses passed in is only used for setting up
1152  * the association.  It does not necessarily equal the set of addresses
1153  * the peer uses for the resulting association.  If the caller wants to
1154  * find out the set of peer addresses, it must use sctp_getpaddrs() to
1155  * retrieve them after the association has been set up.
1156  *
1157  * Basically do nothing but copying the addresses from user to kernel
1158  * land and invoking either sctp_connectx(). This is used for tunneling
1159  * the sctp_connectx() request through sctp_setsockopt() from userspace.
1160  *
1161  * We don't use copy_from_user() for optimization: we first do the
1162  * sanity checks (buffer size -fast- and access check-healthy
1163  * pointer); if all of those succeed, then we can alloc the memory
1164  * (expensive operation) needed to copy the data to kernel. Then we do
1165  * the copying without checking the user space area
1166  * (__copy_from_user()).
1167  *
1168  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
1169  * it.
1170  *
1171  * sk        The sk of the socket
1172  * addrs     The pointer to the addresses in user land
1173  * addrssize Size of the addrs buffer
1174  *
1175  * Returns 0 if ok, <0 errno code on error.
1176  */
1177 SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
1178 				      struct sockaddr __user *addrs,
1179 				      int addrs_size)
1180 {
1181 	int err = 0;
1182 	struct sockaddr *kaddrs;
1183 
1184 	SCTP_DEBUG_PRINTK("%s - sk %p addrs %p addrs_size %d\n",
1185 			  __FUNCTION__, sk, addrs, addrs_size);
1186 
1187 	if (unlikely(addrs_size <= 0))
1188 		return -EINVAL;
1189 
1190 	/* Check the user passed a healthy pointer.  */
1191 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
1192 		return -EFAULT;
1193 
1194 	/* Alloc space for the address array in kernel memory.  */
1195 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
1196 	if (unlikely(!kaddrs))
1197 		return -ENOMEM;
1198 
1199 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
1200 		err = -EFAULT;
1201 	} else {
1202 		err = __sctp_connect(sk, kaddrs, addrs_size);
1203 	}
1204 
1205 	kfree(kaddrs);
1206 	return err;
1207 }
1208 
1209 /* API 3.1.4 close() - UDP Style Syntax
1210  * Applications use close() to perform graceful shutdown (as described in
1211  * Section 10.1 of [SCTP]) on ALL the associations currently represented
1212  * by a UDP-style socket.
1213  *
1214  * The syntax is
1215  *
1216  *   ret = close(int sd);
1217  *
1218  *   sd      - the socket descriptor of the associations to be closed.
1219  *
1220  * To gracefully shutdown a specific association represented by the
1221  * UDP-style socket, an application should use the sendmsg() call,
1222  * passing no user data, but including the appropriate flag in the
1223  * ancillary data (see Section xxxx).
1224  *
1225  * If sd in the close() call is a branched-off socket representing only
1226  * one association, the shutdown is performed on that association only.
1227  *
1228  * 4.1.6 close() - TCP Style Syntax
1229  *
1230  * Applications use close() to gracefully close down an association.
1231  *
1232  * The syntax is:
1233  *
1234  *    int close(int sd);
1235  *
1236  *      sd      - the socket descriptor of the association to be closed.
1237  *
1238  * After an application calls close() on a socket descriptor, no further
1239  * socket operations will succeed on that descriptor.
1240  *
1241  * API 7.1.4 SO_LINGER
1242  *
1243  * An application using the TCP-style socket can use this option to
1244  * perform the SCTP ABORT primitive.  The linger option structure is:
1245  *
1246  *  struct  linger {
1247  *     int     l_onoff;                // option on/off
1248  *     int     l_linger;               // linger time
1249  * };
1250  *
1251  * To enable the option, set l_onoff to 1.  If the l_linger value is set
1252  * to 0, calling close() is the same as the ABORT primitive.  If the
1253  * value is set to a negative value, the setsockopt() call will return
1254  * an error.  If the value is set to a positive value linger_time, the
1255  * close() can be blocked for at most linger_time ms.  If the graceful
1256  * shutdown phase does not finish during this period, close() will
1257  * return but the graceful shutdown phase continues in the system.
1258  */
1259 SCTP_STATIC void sctp_close(struct sock *sk, long timeout)
1260 {
1261 	struct sctp_endpoint *ep;
1262 	struct sctp_association *asoc;
1263 	struct list_head *pos, *temp;
1264 
1265 	SCTP_DEBUG_PRINTK("sctp_close(sk: 0x%p, timeout:%ld)\n", sk, timeout);
1266 
1267 	sctp_lock_sock(sk);
1268 	sk->sk_shutdown = SHUTDOWN_MASK;
1269 
1270 	ep = sctp_sk(sk)->ep;
1271 
1272 	/* Walk all associations on an endpoint.  */
1273 	list_for_each_safe(pos, temp, &ep->asocs) {
1274 		asoc = list_entry(pos, struct sctp_association, asocs);
1275 
1276 		if (sctp_style(sk, TCP)) {
1277 			/* A closed association can still be in the list if
1278 			 * it belongs to a TCP-style listening socket that is
1279 			 * not yet accepted. If so, free it. If not, send an
1280 			 * ABORT or SHUTDOWN based on the linger options.
1281 			 */
1282 			if (sctp_state(asoc, CLOSED)) {
1283 				sctp_unhash_established(asoc);
1284 				sctp_association_free(asoc);
1285 				continue;
1286 			}
1287 		}
1288 
1289 		if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
1290 			struct sctp_chunk *chunk;
1291 
1292 			chunk = sctp_make_abort_user(asoc, NULL, 0);
1293 			if (chunk)
1294 				sctp_primitive_ABORT(asoc, chunk);
1295 		} else
1296 			sctp_primitive_SHUTDOWN(asoc, NULL);
1297 	}
1298 
1299 	/* Clean up any skbs sitting on the receive queue.  */
1300 	sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
1301 	sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
1302 
1303 	/* On a TCP-style socket, block for at most linger_time if set. */
1304 	if (sctp_style(sk, TCP) && timeout)
1305 		sctp_wait_for_close(sk, timeout);
1306 
1307 	/* This will run the backlog queue.  */
1308 	sctp_release_sock(sk);
1309 
1310 	/* Supposedly, no process has access to the socket, but
1311 	 * the net layers still may.
1312 	 */
1313 	sctp_local_bh_disable();
1314 	sctp_bh_lock_sock(sk);
1315 
1316 	/* Hold the sock, since sk_common_release() will put sock_put()
1317 	 * and we have just a little more cleanup.
1318 	 */
1319 	sock_hold(sk);
1320 	sk_common_release(sk);
1321 
1322 	sctp_bh_unlock_sock(sk);
1323 	sctp_local_bh_enable();
1324 
1325 	sock_put(sk);
1326 
1327 	SCTP_DBG_OBJCNT_DEC(sock);
1328 }
1329 
1330 /* Handle EPIPE error. */
1331 static int sctp_error(struct sock *sk, int flags, int err)
1332 {
1333 	if (err == -EPIPE)
1334 		err = sock_error(sk) ? : -EPIPE;
1335 	if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
1336 		send_sig(SIGPIPE, current, 0);
1337 	return err;
1338 }
1339 
1340 /* API 3.1.3 sendmsg() - UDP Style Syntax
1341  *
1342  * An application uses sendmsg() and recvmsg() calls to transmit data to
1343  * and receive data from its peer.
1344  *
1345  *  ssize_t sendmsg(int socket, const struct msghdr *message,
1346  *                  int flags);
1347  *
1348  *  socket  - the socket descriptor of the endpoint.
1349  *  message - pointer to the msghdr structure which contains a single
1350  *            user message and possibly some ancillary data.
1351  *
1352  *            See Section 5 for complete description of the data
1353  *            structures.
1354  *
1355  *  flags   - flags sent or received with the user message, see Section
1356  *            5 for complete description of the flags.
1357  *
1358  * Note:  This function could use a rewrite especially when explicit
1359  * connect support comes in.
1360  */
1361 /* BUG:  We do not implement the equivalent of sk_stream_wait_memory(). */
1362 
1363 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
1364 
1365 SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
1366 			     struct msghdr *msg, size_t msg_len)
1367 {
1368 	struct sctp_sock *sp;
1369 	struct sctp_endpoint *ep;
1370 	struct sctp_association *new_asoc=NULL, *asoc=NULL;
1371 	struct sctp_transport *transport, *chunk_tp;
1372 	struct sctp_chunk *chunk;
1373 	union sctp_addr to;
1374 	struct sockaddr *msg_name = NULL;
1375 	struct sctp_sndrcvinfo default_sinfo = { 0 };
1376 	struct sctp_sndrcvinfo *sinfo;
1377 	struct sctp_initmsg *sinit;
1378 	sctp_assoc_t associd = 0;
1379 	sctp_cmsgs_t cmsgs = { NULL };
1380 	int err;
1381 	sctp_scope_t scope;
1382 	long timeo;
1383 	__u16 sinfo_flags = 0;
1384 	struct sctp_datamsg *datamsg;
1385 	struct list_head *pos;
1386 	int msg_flags = msg->msg_flags;
1387 
1388 	SCTP_DEBUG_PRINTK("sctp_sendmsg(sk: %p, msg: %p, msg_len: %zu)\n",
1389 			  sk, msg, msg_len);
1390 
1391 	err = 0;
1392 	sp = sctp_sk(sk);
1393 	ep = sp->ep;
1394 
1395 	SCTP_DEBUG_PRINTK("Using endpoint: %p.\n", ep);
1396 
1397 	/* We cannot send a message over a TCP-style listening socket. */
1398 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) {
1399 		err = -EPIPE;
1400 		goto out_nounlock;
1401 	}
1402 
1403 	/* Parse out the SCTP CMSGs.  */
1404 	err = sctp_msghdr_parse(msg, &cmsgs);
1405 
1406 	if (err) {
1407 		SCTP_DEBUG_PRINTK("msghdr parse err = %x\n", err);
1408 		goto out_nounlock;
1409 	}
1410 
1411 	/* Fetch the destination address for this packet.  This
1412 	 * address only selects the association--it is not necessarily
1413 	 * the address we will send to.
1414 	 * For a peeled-off socket, msg_name is ignored.
1415 	 */
1416 	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
1417 		int msg_namelen = msg->msg_namelen;
1418 
1419 		err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
1420 				       msg_namelen);
1421 		if (err)
1422 			return err;
1423 
1424 		if (msg_namelen > sizeof(to))
1425 			msg_namelen = sizeof(to);
1426 		memcpy(&to, msg->msg_name, msg_namelen);
1427 		msg_name = msg->msg_name;
1428 	}
1429 
1430 	sinfo = cmsgs.info;
1431 	sinit = cmsgs.init;
1432 
1433 	/* Did the user specify SNDRCVINFO?  */
1434 	if (sinfo) {
1435 		sinfo_flags = sinfo->sinfo_flags;
1436 		associd = sinfo->sinfo_assoc_id;
1437 	}
1438 
1439 	SCTP_DEBUG_PRINTK("msg_len: %zu, sinfo_flags: 0x%x\n",
1440 			  msg_len, sinfo_flags);
1441 
1442 	/* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */
1443 	if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) {
1444 		err = -EINVAL;
1445 		goto out_nounlock;
1446 	}
1447 
1448 	/* If SCTP_EOF is set, no data can be sent. Disallow sending zero
1449 	 * length messages when SCTP_EOF|SCTP_ABORT is not set.
1450 	 * If SCTP_ABORT is set, the message length could be non zero with
1451 	 * the msg_iov set to the user abort reason.
1452 	 */
1453 	if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) ||
1454 	    (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) {
1455 		err = -EINVAL;
1456 		goto out_nounlock;
1457 	}
1458 
1459 	/* If SCTP_ADDR_OVER is set, there must be an address
1460 	 * specified in msg_name.
1461 	 */
1462 	if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) {
1463 		err = -EINVAL;
1464 		goto out_nounlock;
1465 	}
1466 
1467 	transport = NULL;
1468 
1469 	SCTP_DEBUG_PRINTK("About to look up association.\n");
1470 
1471 	sctp_lock_sock(sk);
1472 
1473 	/* If a msg_name has been specified, assume this is to be used.  */
1474 	if (msg_name) {
1475 		/* Look for a matching association on the endpoint. */
1476 		asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1477 		if (!asoc) {
1478 			/* If we could not find a matching association on the
1479 			 * endpoint, make sure that it is not a TCP-style
1480 			 * socket that already has an association or there is
1481 			 * no peeled-off association on another socket.
1482 			 */
1483 			if ((sctp_style(sk, TCP) &&
1484 			     sctp_sstate(sk, ESTABLISHED)) ||
1485 			    sctp_endpoint_is_peeled_off(ep, &to)) {
1486 				err = -EADDRNOTAVAIL;
1487 				goto out_unlock;
1488 			}
1489 		}
1490 	} else {
1491 		asoc = sctp_id2assoc(sk, associd);
1492 		if (!asoc) {
1493 			err = -EPIPE;
1494 			goto out_unlock;
1495 		}
1496 	}
1497 
1498 	if (asoc) {
1499 		SCTP_DEBUG_PRINTK("Just looked up association: %p.\n", asoc);
1500 
1501 		/* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED
1502 		 * socket that has an association in CLOSED state. This can
1503 		 * happen when an accepted socket has an association that is
1504 		 * already CLOSED.
1505 		 */
1506 		if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) {
1507 			err = -EPIPE;
1508 			goto out_unlock;
1509 		}
1510 
1511 		if (sinfo_flags & SCTP_EOF) {
1512 			SCTP_DEBUG_PRINTK("Shutting down association: %p\n",
1513 					  asoc);
1514 			sctp_primitive_SHUTDOWN(asoc, NULL);
1515 			err = 0;
1516 			goto out_unlock;
1517 		}
1518 		if (sinfo_flags & SCTP_ABORT) {
1519 			struct sctp_chunk *chunk;
1520 
1521 			chunk = sctp_make_abort_user(asoc, msg, msg_len);
1522 			if (!chunk) {
1523 				err = -ENOMEM;
1524 				goto out_unlock;
1525 			}
1526 
1527 			SCTP_DEBUG_PRINTK("Aborting association: %p\n", asoc);
1528 			sctp_primitive_ABORT(asoc, chunk);
1529 			err = 0;
1530 			goto out_unlock;
1531 		}
1532 	}
1533 
1534 	/* Do we need to create the association?  */
1535 	if (!asoc) {
1536 		SCTP_DEBUG_PRINTK("There is no association yet.\n");
1537 
1538 		if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) {
1539 			err = -EINVAL;
1540 			goto out_unlock;
1541 		}
1542 
1543 		/* Check for invalid stream against the stream counts,
1544 		 * either the default or the user specified stream counts.
1545 		 */
1546 		if (sinfo) {
1547 			if (!sinit || (sinit && !sinit->sinit_num_ostreams)) {
1548 				/* Check against the defaults. */
1549 				if (sinfo->sinfo_stream >=
1550 				    sp->initmsg.sinit_num_ostreams) {
1551 					err = -EINVAL;
1552 					goto out_unlock;
1553 				}
1554 			} else {
1555 				/* Check against the requested.  */
1556 				if (sinfo->sinfo_stream >=
1557 				    sinit->sinit_num_ostreams) {
1558 					err = -EINVAL;
1559 					goto out_unlock;
1560 				}
1561 			}
1562 		}
1563 
1564 		/*
1565 		 * API 3.1.2 bind() - UDP Style Syntax
1566 		 * If a bind() or sctp_bindx() is not called prior to a
1567 		 * sendmsg() call that initiates a new association, the
1568 		 * system picks an ephemeral port and will choose an address
1569 		 * set equivalent to binding with a wildcard address.
1570 		 */
1571 		if (!ep->base.bind_addr.port) {
1572 			if (sctp_autobind(sk)) {
1573 				err = -EAGAIN;
1574 				goto out_unlock;
1575 			}
1576 		} else {
1577 			/*
1578 			 * If an unprivileged user inherits a one-to-many
1579 			 * style socket with open associations on a privileged
1580 			 * port, it MAY be permitted to accept new associations,
1581 			 * but it SHOULD NOT be permitted to open new
1582 			 * associations.
1583 			 */
1584 			if (ep->base.bind_addr.port < PROT_SOCK &&
1585 			    !capable(CAP_NET_BIND_SERVICE)) {
1586 				err = -EACCES;
1587 				goto out_unlock;
1588 			}
1589 		}
1590 
1591 		scope = sctp_scope(&to);
1592 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1593 		if (!new_asoc) {
1594 			err = -ENOMEM;
1595 			goto out_unlock;
1596 		}
1597 		asoc = new_asoc;
1598 
1599 		/* If the SCTP_INIT ancillary data is specified, set all
1600 		 * the association init values accordingly.
1601 		 */
1602 		if (sinit) {
1603 			if (sinit->sinit_num_ostreams) {
1604 				asoc->c.sinit_num_ostreams =
1605 					sinit->sinit_num_ostreams;
1606 			}
1607 			if (sinit->sinit_max_instreams) {
1608 				asoc->c.sinit_max_instreams =
1609 					sinit->sinit_max_instreams;
1610 			}
1611 			if (sinit->sinit_max_attempts) {
1612 				asoc->max_init_attempts
1613 					= sinit->sinit_max_attempts;
1614 			}
1615 			if (sinit->sinit_max_init_timeo) {
1616 				asoc->max_init_timeo =
1617 				 msecs_to_jiffies(sinit->sinit_max_init_timeo);
1618 			}
1619 		}
1620 
1621 		/* Prime the peer's transport structures.  */
1622 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN);
1623 		if (!transport) {
1624 			err = -ENOMEM;
1625 			goto out_free;
1626 		}
1627 		err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
1628 		if (err < 0) {
1629 			err = -ENOMEM;
1630 			goto out_free;
1631 		}
1632 	}
1633 
1634 	/* ASSERT: we have a valid association at this point.  */
1635 	SCTP_DEBUG_PRINTK("We have a valid association.\n");
1636 
1637 	if (!sinfo) {
1638 		/* If the user didn't specify SNDRCVINFO, make up one with
1639 		 * some defaults.
1640 		 */
1641 		default_sinfo.sinfo_stream = asoc->default_stream;
1642 		default_sinfo.sinfo_flags = asoc->default_flags;
1643 		default_sinfo.sinfo_ppid = asoc->default_ppid;
1644 		default_sinfo.sinfo_context = asoc->default_context;
1645 		default_sinfo.sinfo_timetolive = asoc->default_timetolive;
1646 		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
1647 		sinfo = &default_sinfo;
1648 	}
1649 
1650 	/* API 7.1.7, the sndbuf size per association bounds the
1651 	 * maximum size of data that can be sent in a single send call.
1652 	 */
1653 	if (msg_len > sk->sk_sndbuf) {
1654 		err = -EMSGSIZE;
1655 		goto out_free;
1656 	}
1657 
1658 	/* If fragmentation is disabled and the message length exceeds the
1659 	 * association fragmentation point, return EMSGSIZE.  The I-D
1660 	 * does not specify what this error is, but this looks like
1661 	 * a great fit.
1662 	 */
1663 	if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
1664 		err = -EMSGSIZE;
1665 		goto out_free;
1666 	}
1667 
1668 	if (sinfo) {
1669 		/* Check for invalid stream. */
1670 		if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) {
1671 			err = -EINVAL;
1672 			goto out_free;
1673 		}
1674 	}
1675 
1676 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1677 	if (!sctp_wspace(asoc)) {
1678 		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
1679 		if (err)
1680 			goto out_free;
1681 	}
1682 
1683 	/* If an address is passed with the sendto/sendmsg call, it is used
1684 	 * to override the primary destination address in the TCP model, or
1685 	 * when SCTP_ADDR_OVER flag is set in the UDP model.
1686 	 */
1687 	if ((sctp_style(sk, TCP) && msg_name) ||
1688 	    (sinfo_flags & SCTP_ADDR_OVER)) {
1689 		chunk_tp = sctp_assoc_lookup_paddr(asoc, &to);
1690 		if (!chunk_tp) {
1691 			err = -EINVAL;
1692 			goto out_free;
1693 		}
1694 	} else
1695 		chunk_tp = NULL;
1696 
1697 	/* Auto-connect, if we aren't connected already. */
1698 	if (sctp_state(asoc, CLOSED)) {
1699 		err = sctp_primitive_ASSOCIATE(asoc, NULL);
1700 		if (err < 0)
1701 			goto out_free;
1702 		SCTP_DEBUG_PRINTK("We associated primitively.\n");
1703 	}
1704 
1705 	/* Break the message into multiple chunks of maximum size. */
1706 	datamsg = sctp_datamsg_from_user(asoc, sinfo, msg, msg_len);
1707 	if (!datamsg) {
1708 		err = -ENOMEM;
1709 		goto out_free;
1710 	}
1711 
1712 	/* Now send the (possibly) fragmented message. */
1713 	list_for_each(pos, &datamsg->chunks) {
1714 		chunk = list_entry(pos, struct sctp_chunk, frag_list);
1715 		sctp_datamsg_track(chunk);
1716 
1717 		/* Do accounting for the write space.  */
1718 		sctp_set_owner_w(chunk);
1719 
1720 		chunk->transport = chunk_tp;
1721 
1722 		/* Send it to the lower layers.  Note:  all chunks
1723 		 * must either fail or succeed.   The lower layer
1724 		 * works that way today.  Keep it that way or this
1725 		 * breaks.
1726 		 */
1727 		err = sctp_primitive_SEND(asoc, chunk);
1728 		/* Did the lower layer accept the chunk? */
1729 		if (err)
1730 			sctp_chunk_free(chunk);
1731 		SCTP_DEBUG_PRINTK("We sent primitively.\n");
1732 	}
1733 
1734 	sctp_datamsg_free(datamsg);
1735 	if (err)
1736 		goto out_free;
1737 	else
1738 		err = msg_len;
1739 
1740 	/* If we are already past ASSOCIATE, the lower
1741 	 * layers are responsible for association cleanup.
1742 	 */
1743 	goto out_unlock;
1744 
1745 out_free:
1746 	if (new_asoc)
1747 		sctp_association_free(asoc);
1748 out_unlock:
1749 	sctp_release_sock(sk);
1750 
1751 out_nounlock:
1752 	return sctp_error(sk, msg_flags, err);
1753 
1754 #if 0
1755 do_sock_err:
1756 	if (msg_len)
1757 		err = msg_len;
1758 	else
1759 		err = sock_error(sk);
1760 	goto out;
1761 
1762 do_interrupted:
1763 	if (msg_len)
1764 		err = msg_len;
1765 	goto out;
1766 #endif /* 0 */
1767 }
1768 
1769 /* This is an extended version of skb_pull() that removes the data from the
1770  * start of a skb even when data is spread across the list of skb's in the
1771  * frag_list. len specifies the total amount of data that needs to be removed.
1772  * when 'len' bytes could be removed from the skb, it returns 0.
1773  * If 'len' exceeds the total skb length,  it returns the no. of bytes that
1774  * could not be removed.
1775  */
1776 static int sctp_skb_pull(struct sk_buff *skb, int len)
1777 {
1778 	struct sk_buff *list;
1779 	int skb_len = skb_headlen(skb);
1780 	int rlen;
1781 
1782 	if (len <= skb_len) {
1783 		__skb_pull(skb, len);
1784 		return 0;
1785 	}
1786 	len -= skb_len;
1787 	__skb_pull(skb, skb_len);
1788 
1789 	for (list = skb_shinfo(skb)->frag_list; list; list = list->next) {
1790 		rlen = sctp_skb_pull(list, len);
1791 		skb->len -= (len-rlen);
1792 		skb->data_len -= (len-rlen);
1793 
1794 		if (!rlen)
1795 			return 0;
1796 
1797 		len = rlen;
1798 	}
1799 
1800 	return len;
1801 }
1802 
1803 /* API 3.1.3  recvmsg() - UDP Style Syntax
1804  *
1805  *  ssize_t recvmsg(int socket, struct msghdr *message,
1806  *                    int flags);
1807  *
1808  *  socket  - the socket descriptor of the endpoint.
1809  *  message - pointer to the msghdr structure which contains a single
1810  *            user message and possibly some ancillary data.
1811  *
1812  *            See Section 5 for complete description of the data
1813  *            structures.
1814  *
1815  *  flags   - flags sent or received with the user message, see Section
1816  *            5 for complete description of the flags.
1817  */
1818 static struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);
1819 
1820 SCTP_STATIC int sctp_recvmsg(struct kiocb *iocb, struct sock *sk,
1821 			     struct msghdr *msg, size_t len, int noblock,
1822 			     int flags, int *addr_len)
1823 {
1824 	struct sctp_ulpevent *event = NULL;
1825 	struct sctp_sock *sp = sctp_sk(sk);
1826 	struct sk_buff *skb;
1827 	int copied;
1828 	int err = 0;
1829 	int skb_len;
1830 
1831 	SCTP_DEBUG_PRINTK("sctp_recvmsg(%s: %p, %s: %p, %s: %zd, %s: %d, %s: "
1832 			  "0x%x, %s: %p)\n", "sk", sk, "msghdr", msg,
1833 			  "len", len, "knoblauch", noblock,
1834 			  "flags", flags, "addr_len", addr_len);
1835 
1836 	sctp_lock_sock(sk);
1837 
1838 	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED)) {
1839 		err = -ENOTCONN;
1840 		goto out;
1841 	}
1842 
1843 	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
1844 	if (!skb)
1845 		goto out;
1846 
1847 	/* Get the total length of the skb including any skb's in the
1848 	 * frag_list.
1849 	 */
1850 	skb_len = skb->len;
1851 
1852 	copied = skb_len;
1853 	if (copied > len)
1854 		copied = len;
1855 
1856 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1857 
1858 	event = sctp_skb2event(skb);
1859 
1860 	if (err)
1861 		goto out_free;
1862 
1863 	sock_recv_timestamp(msg, sk, skb);
1864 	if (sctp_ulpevent_is_notification(event)) {
1865 		msg->msg_flags |= MSG_NOTIFICATION;
1866 		sp->pf->event_msgname(event, msg->msg_name, addr_len);
1867 	} else {
1868 		sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
1869 	}
1870 
1871 	/* Check if we allow SCTP_SNDRCVINFO. */
1872 	if (sp->subscribe.sctp_data_io_event)
1873 		sctp_ulpevent_read_sndrcvinfo(event, msg);
1874 #if 0
1875 	/* FIXME: we should be calling IP/IPv6 layers.  */
1876 	if (sk->sk_protinfo.af_inet.cmsg_flags)
1877 		ip_cmsg_recv(msg, skb);
1878 #endif
1879 
1880 	err = copied;
1881 
1882 	/* If skb's length exceeds the user's buffer, update the skb and
1883 	 * push it back to the receive_queue so that the next call to
1884 	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
1885 	 */
1886 	if (skb_len > copied) {
1887 		msg->msg_flags &= ~MSG_EOR;
1888 		if (flags & MSG_PEEK)
1889 			goto out_free;
1890 		sctp_skb_pull(skb, copied);
1891 		skb_queue_head(&sk->sk_receive_queue, skb);
1892 
1893 		/* When only partial message is copied to the user, increase
1894 		 * rwnd by that amount. If all the data in the skb is read,
1895 		 * rwnd is updated when the event is freed.
1896 		 */
1897 		sctp_assoc_rwnd_increase(event->asoc, copied);
1898 		goto out;
1899 	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
1900 		   (event->msg_flags & MSG_EOR))
1901 		msg->msg_flags |= MSG_EOR;
1902 	else
1903 		msg->msg_flags &= ~MSG_EOR;
1904 
1905 out_free:
1906 	if (flags & MSG_PEEK) {
1907 		/* Release the skb reference acquired after peeking the skb in
1908 		 * sctp_skb_recv_datagram().
1909 		 */
1910 		kfree_skb(skb);
1911 	} else {
1912 		/* Free the event which includes releasing the reference to
1913 		 * the owner of the skb, freeing the skb and updating the
1914 		 * rwnd.
1915 		 */
1916 		sctp_ulpevent_free(event);
1917 	}
1918 out:
1919 	sctp_release_sock(sk);
1920 	return err;
1921 }
1922 
1923 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
1924  *
1925  * This option is a on/off flag.  If enabled no SCTP message
1926  * fragmentation will be performed.  Instead if a message being sent
1927  * exceeds the current PMTU size, the message will NOT be sent and
1928  * instead a error will be indicated to the user.
1929  */
1930 static int sctp_setsockopt_disable_fragments(struct sock *sk,
1931 					    char __user *optval, int optlen)
1932 {
1933 	int val;
1934 
1935 	if (optlen < sizeof(int))
1936 		return -EINVAL;
1937 
1938 	if (get_user(val, (int __user *)optval))
1939 		return -EFAULT;
1940 
1941 	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
1942 
1943 	return 0;
1944 }
1945 
1946 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
1947 					int optlen)
1948 {
1949 	if (optlen != sizeof(struct sctp_event_subscribe))
1950 		return -EINVAL;
1951 	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
1952 		return -EFAULT;
1953 	return 0;
1954 }
1955 
1956 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
1957  *
1958  * This socket option is applicable to the UDP-style socket only.  When
1959  * set it will cause associations that are idle for more than the
1960  * specified number of seconds to automatically close.  An association
1961  * being idle is defined an association that has NOT sent or received
1962  * user data.  The special value of '0' indicates that no automatic
1963  * close of any associations should be performed.  The option expects an
1964  * integer defining the number of seconds of idle time before an
1965  * association is closed.
1966  */
1967 static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
1968 					    int optlen)
1969 {
1970 	struct sctp_sock *sp = sctp_sk(sk);
1971 
1972 	/* Applicable to UDP-style socket only */
1973 	if (sctp_style(sk, TCP))
1974 		return -EOPNOTSUPP;
1975 	if (optlen != sizeof(int))
1976 		return -EINVAL;
1977 	if (copy_from_user(&sp->autoclose, optval, optlen))
1978 		return -EFAULT;
1979 
1980 	return 0;
1981 }
1982 
1983 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
1984  *
1985  * Applications can enable or disable heartbeats for any peer address of
1986  * an association, modify an address's heartbeat interval, force a
1987  * heartbeat to be sent immediately, and adjust the address's maximum
1988  * number of retransmissions sent before an address is considered
1989  * unreachable.  The following structure is used to access and modify an
1990  * address's parameters:
1991  *
1992  *  struct sctp_paddrparams {
1993  *     sctp_assoc_t            spp_assoc_id;
1994  *     struct sockaddr_storage spp_address;
1995  *     uint32_t                spp_hbinterval;
1996  *     uint16_t                spp_pathmaxrxt;
1997  *     uint32_t                spp_pathmtu;
1998  *     uint32_t                spp_sackdelay;
1999  *     uint32_t                spp_flags;
2000  * };
2001  *
2002  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
2003  *                     application, and identifies the association for
2004  *                     this query.
2005  *   spp_address     - This specifies which address is of interest.
2006  *   spp_hbinterval  - This contains the value of the heartbeat interval,
2007  *                     in milliseconds.  If a  value of zero
2008  *                     is present in this field then no changes are to
2009  *                     be made to this parameter.
2010  *   spp_pathmaxrxt  - This contains the maximum number of
2011  *                     retransmissions before this address shall be
2012  *                     considered unreachable. If a  value of zero
2013  *                     is present in this field then no changes are to
2014  *                     be made to this parameter.
2015  *   spp_pathmtu     - When Path MTU discovery is disabled the value
2016  *                     specified here will be the "fixed" path mtu.
2017  *                     Note that if the spp_address field is empty
2018  *                     then all associations on this address will
2019  *                     have this fixed path mtu set upon them.
2020  *
2021  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
2022  *                     the number of milliseconds that sacks will be delayed
2023  *                     for. This value will apply to all addresses of an
2024  *                     association if the spp_address field is empty. Note
2025  *                     also, that if delayed sack is enabled and this
2026  *                     value is set to 0, no change is made to the last
2027  *                     recorded delayed sack timer value.
2028  *
2029  *   spp_flags       - These flags are used to control various features
2030  *                     on an association. The flag field may contain
2031  *                     zero or more of the following options.
2032  *
2033  *                     SPP_HB_ENABLE  - Enable heartbeats on the
2034  *                     specified address. Note that if the address
2035  *                     field is empty all addresses for the association
2036  *                     have heartbeats enabled upon them.
2037  *
2038  *                     SPP_HB_DISABLE - Disable heartbeats on the
2039  *                     speicifed address. Note that if the address
2040  *                     field is empty all addresses for the association
2041  *                     will have their heartbeats disabled. Note also
2042  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
2043  *                     mutually exclusive, only one of these two should
2044  *                     be specified. Enabling both fields will have
2045  *                     undetermined results.
2046  *
2047  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
2048  *                     to be made immediately.
2049  *
2050  *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
2051  *                     heartbeat delayis to be set to the value of 0
2052  *                     milliseconds.
2053  *
2054  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
2055  *                     discovery upon the specified address. Note that
2056  *                     if the address feild is empty then all addresses
2057  *                     on the association are effected.
2058  *
2059  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
2060  *                     discovery upon the specified address. Note that
2061  *                     if the address feild is empty then all addresses
2062  *                     on the association are effected. Not also that
2063  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
2064  *                     exclusive. Enabling both will have undetermined
2065  *                     results.
2066  *
2067  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
2068  *                     on delayed sack. The time specified in spp_sackdelay
2069  *                     is used to specify the sack delay for this address. Note
2070  *                     that if spp_address is empty then all addresses will
2071  *                     enable delayed sack and take on the sack delay
2072  *                     value specified in spp_sackdelay.
2073  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
2074  *                     off delayed sack. If the spp_address field is blank then
2075  *                     delayed sack is disabled for the entire association. Note
2076  *                     also that this field is mutually exclusive to
2077  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
2078  *                     results.
2079  */
2080 static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
2081 				       struct sctp_transport   *trans,
2082 				       struct sctp_association *asoc,
2083 				       struct sctp_sock        *sp,
2084 				       int                      hb_change,
2085 				       int                      pmtud_change,
2086 				       int                      sackdelay_change)
2087 {
2088 	int error;
2089 
2090 	if (params->spp_flags & SPP_HB_DEMAND && trans) {
2091 		error = sctp_primitive_REQUESTHEARTBEAT (trans->asoc, trans);
2092 		if (error)
2093 			return error;
2094 	}
2095 
2096 	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
2097 	 * this field is ignored.  Note also that a value of zero indicates
2098 	 * the current setting should be left unchanged.
2099 	 */
2100 	if (params->spp_flags & SPP_HB_ENABLE) {
2101 
2102 		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
2103 		 * set.  This lets us use 0 value when this flag
2104 		 * is set.
2105 		 */
2106 		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
2107 			params->spp_hbinterval = 0;
2108 
2109 		if (params->spp_hbinterval ||
2110 		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
2111 			if (trans) {
2112 				trans->hbinterval =
2113 				    msecs_to_jiffies(params->spp_hbinterval);
2114 			} else if (asoc) {
2115 				asoc->hbinterval =
2116 				    msecs_to_jiffies(params->spp_hbinterval);
2117 			} else {
2118 				sp->hbinterval = params->spp_hbinterval;
2119 			}
2120 		}
2121 	}
2122 
2123 	if (hb_change) {
2124 		if (trans) {
2125 			trans->param_flags =
2126 				(trans->param_flags & ~SPP_HB) | hb_change;
2127 		} else if (asoc) {
2128 			asoc->param_flags =
2129 				(asoc->param_flags & ~SPP_HB) | hb_change;
2130 		} else {
2131 			sp->param_flags =
2132 				(sp->param_flags & ~SPP_HB) | hb_change;
2133 		}
2134 	}
2135 
2136 	/* When Path MTU discovery is disabled the value specified here will
2137 	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
2138 	 * include the flag SPP_PMTUD_DISABLE for this field to have any
2139 	 * effect).
2140 	 */
2141 	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
2142 		if (trans) {
2143 			trans->pathmtu = params->spp_pathmtu;
2144 			sctp_assoc_sync_pmtu(asoc);
2145 		} else if (asoc) {
2146 			asoc->pathmtu = params->spp_pathmtu;
2147 			sctp_frag_point(sp, params->spp_pathmtu);
2148 		} else {
2149 			sp->pathmtu = params->spp_pathmtu;
2150 		}
2151 	}
2152 
2153 	if (pmtud_change) {
2154 		if (trans) {
2155 			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
2156 				(params->spp_flags & SPP_PMTUD_ENABLE);
2157 			trans->param_flags =
2158 				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
2159 			if (update) {
2160 				sctp_transport_pmtu(trans);
2161 				sctp_assoc_sync_pmtu(asoc);
2162 			}
2163 		} else if (asoc) {
2164 			asoc->param_flags =
2165 				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
2166 		} else {
2167 			sp->param_flags =
2168 				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
2169 		}
2170 	}
2171 
2172 	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
2173 	 * value of this field is ignored.  Note also that a value of zero
2174 	 * indicates the current setting should be left unchanged.
2175 	 */
2176 	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
2177 		if (trans) {
2178 			trans->sackdelay =
2179 				msecs_to_jiffies(params->spp_sackdelay);
2180 		} else if (asoc) {
2181 			asoc->sackdelay =
2182 				msecs_to_jiffies(params->spp_sackdelay);
2183 		} else {
2184 			sp->sackdelay = params->spp_sackdelay;
2185 		}
2186 	}
2187 
2188 	if (sackdelay_change) {
2189 		if (trans) {
2190 			trans->param_flags =
2191 				(trans->param_flags & ~SPP_SACKDELAY) |
2192 				sackdelay_change;
2193 		} else if (asoc) {
2194 			asoc->param_flags =
2195 				(asoc->param_flags & ~SPP_SACKDELAY) |
2196 				sackdelay_change;
2197 		} else {
2198 			sp->param_flags =
2199 				(sp->param_flags & ~SPP_SACKDELAY) |
2200 				sackdelay_change;
2201 		}
2202 	}
2203 
2204 	/* Note that unless the spp_flag is set to SPP_PMTUD_ENABLE the value
2205 	 * of this field is ignored.  Note also that a value of zero
2206 	 * indicates the current setting should be left unchanged.
2207 	 */
2208 	if ((params->spp_flags & SPP_PMTUD_ENABLE) && params->spp_pathmaxrxt) {
2209 		if (trans) {
2210 			trans->pathmaxrxt = params->spp_pathmaxrxt;
2211 		} else if (asoc) {
2212 			asoc->pathmaxrxt = params->spp_pathmaxrxt;
2213 		} else {
2214 			sp->pathmaxrxt = params->spp_pathmaxrxt;
2215 		}
2216 	}
2217 
2218 	return 0;
2219 }
2220 
2221 static int sctp_setsockopt_peer_addr_params(struct sock *sk,
2222 					    char __user *optval, int optlen)
2223 {
2224 	struct sctp_paddrparams  params;
2225 	struct sctp_transport   *trans = NULL;
2226 	struct sctp_association *asoc = NULL;
2227 	struct sctp_sock        *sp = sctp_sk(sk);
2228 	int error;
2229 	int hb_change, pmtud_change, sackdelay_change;
2230 
2231 	if (optlen != sizeof(struct sctp_paddrparams))
2232 		return - EINVAL;
2233 
2234 	if (copy_from_user(&params, optval, optlen))
2235 		return -EFAULT;
2236 
2237 	/* Validate flags and value parameters. */
2238 	hb_change        = params.spp_flags & SPP_HB;
2239 	pmtud_change     = params.spp_flags & SPP_PMTUD;
2240 	sackdelay_change = params.spp_flags & SPP_SACKDELAY;
2241 
2242 	if (hb_change        == SPP_HB ||
2243 	    pmtud_change     == SPP_PMTUD ||
2244 	    sackdelay_change == SPP_SACKDELAY ||
2245 	    params.spp_sackdelay > 500 ||
2246 	    (params.spp_pathmtu
2247 	    && params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
2248 		return -EINVAL;
2249 
2250 	/* If an address other than INADDR_ANY is specified, and
2251 	 * no transport is found, then the request is invalid.
2252 	 */
2253 	if (!sctp_is_any(( union sctp_addr *)&params.spp_address)) {
2254 		trans = sctp_addr_id2transport(sk, &params.spp_address,
2255 					       params.spp_assoc_id);
2256 		if (!trans)
2257 			return -EINVAL;
2258 	}
2259 
2260 	/* Get association, if assoc_id != 0 and the socket is a one
2261 	 * to many style socket, and an association was not found, then
2262 	 * the id was invalid.
2263 	 */
2264 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
2265 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
2266 		return -EINVAL;
2267 
2268 	/* Heartbeat demand can only be sent on a transport or
2269 	 * association, but not a socket.
2270 	 */
2271 	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
2272 		return -EINVAL;
2273 
2274 	/* Process parameters. */
2275 	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2276 					    hb_change, pmtud_change,
2277 					    sackdelay_change);
2278 
2279 	if (error)
2280 		return error;
2281 
2282 	/* If changes are for association, also apply parameters to each
2283 	 * transport.
2284 	 */
2285 	if (!trans && asoc) {
2286 		struct list_head *pos;
2287 
2288 		list_for_each(pos, &asoc->peer.transport_addr_list) {
2289 			trans = list_entry(pos, struct sctp_transport,
2290 					   transports);
2291 			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2292 						    hb_change, pmtud_change,
2293 						    sackdelay_change);
2294 		}
2295 	}
2296 
2297 	return 0;
2298 }
2299 
2300 /* 7.1.23. Delayed Ack Timer (SCTP_DELAYED_ACK_TIME)
2301  *
2302  *   This options will get or set the delayed ack timer.  The time is set
2303  *   in milliseconds.  If the assoc_id is 0, then this sets or gets the
2304  *   endpoints default delayed ack timer value.  If the assoc_id field is
2305  *   non-zero, then the set or get effects the specified association.
2306  *
2307  *   struct sctp_assoc_value {
2308  *       sctp_assoc_t            assoc_id;
2309  *       uint32_t                assoc_value;
2310  *   };
2311  *
2312  *     assoc_id    - This parameter, indicates which association the
2313  *                   user is preforming an action upon. Note that if
2314  *                   this field's value is zero then the endpoints
2315  *                   default value is changed (effecting future
2316  *                   associations only).
2317  *
2318  *     assoc_value - This parameter contains the number of milliseconds
2319  *                   that the user is requesting the delayed ACK timer
2320  *                   be set to. Note that this value is defined in
2321  *                   the standard to be between 200 and 500 milliseconds.
2322  *
2323  *                   Note: a value of zero will leave the value alone,
2324  *                   but disable SACK delay. A non-zero value will also
2325  *                   enable SACK delay.
2326  */
2327 
2328 static int sctp_setsockopt_delayed_ack_time(struct sock *sk,
2329 					    char __user *optval, int optlen)
2330 {
2331 	struct sctp_assoc_value  params;
2332 	struct sctp_transport   *trans = NULL;
2333 	struct sctp_association *asoc = NULL;
2334 	struct sctp_sock        *sp = sctp_sk(sk);
2335 
2336 	if (optlen != sizeof(struct sctp_assoc_value))
2337 		return - EINVAL;
2338 
2339 	if (copy_from_user(&params, optval, optlen))
2340 		return -EFAULT;
2341 
2342 	/* Validate value parameter. */
2343 	if (params.assoc_value > 500)
2344 		return -EINVAL;
2345 
2346 	/* Get association, if assoc_id != 0 and the socket is a one
2347 	 * to many style socket, and an association was not found, then
2348 	 * the id was invalid.
2349 	 */
2350 	asoc = sctp_id2assoc(sk, params.assoc_id);
2351 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
2352 		return -EINVAL;
2353 
2354 	if (params.assoc_value) {
2355 		if (asoc) {
2356 			asoc->sackdelay =
2357 				msecs_to_jiffies(params.assoc_value);
2358 			asoc->param_flags =
2359 				(asoc->param_flags & ~SPP_SACKDELAY) |
2360 				SPP_SACKDELAY_ENABLE;
2361 		} else {
2362 			sp->sackdelay = params.assoc_value;
2363 			sp->param_flags =
2364 				(sp->param_flags & ~SPP_SACKDELAY) |
2365 				SPP_SACKDELAY_ENABLE;
2366 		}
2367 	} else {
2368 		if (asoc) {
2369 			asoc->param_flags =
2370 				(asoc->param_flags & ~SPP_SACKDELAY) |
2371 				SPP_SACKDELAY_DISABLE;
2372 		} else {
2373 			sp->param_flags =
2374 				(sp->param_flags & ~SPP_SACKDELAY) |
2375 				SPP_SACKDELAY_DISABLE;
2376 		}
2377 	}
2378 
2379 	/* If change is for association, also apply to each transport. */
2380 	if (asoc) {
2381 		struct list_head *pos;
2382 
2383 		list_for_each(pos, &asoc->peer.transport_addr_list) {
2384 			trans = list_entry(pos, struct sctp_transport,
2385 					   transports);
2386 			if (params.assoc_value) {
2387 				trans->sackdelay =
2388 					msecs_to_jiffies(params.assoc_value);
2389 				trans->param_flags =
2390 					(trans->param_flags & ~SPP_SACKDELAY) |
2391 					SPP_SACKDELAY_ENABLE;
2392 			} else {
2393 				trans->param_flags =
2394 					(trans->param_flags & ~SPP_SACKDELAY) |
2395 					SPP_SACKDELAY_DISABLE;
2396 			}
2397 		}
2398 	}
2399 
2400 	return 0;
2401 }
2402 
2403 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
2404  *
2405  * Applications can specify protocol parameters for the default association
2406  * initialization.  The option name argument to setsockopt() and getsockopt()
2407  * is SCTP_INITMSG.
2408  *
2409  * Setting initialization parameters is effective only on an unconnected
2410  * socket (for UDP-style sockets only future associations are effected
2411  * by the change).  With TCP-style sockets, this option is inherited by
2412  * sockets derived from a listener socket.
2413  */
2414 static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, int optlen)
2415 {
2416 	struct sctp_initmsg sinit;
2417 	struct sctp_sock *sp = sctp_sk(sk);
2418 
2419 	if (optlen != sizeof(struct sctp_initmsg))
2420 		return -EINVAL;
2421 	if (copy_from_user(&sinit, optval, optlen))
2422 		return -EFAULT;
2423 
2424 	if (sinit.sinit_num_ostreams)
2425 		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
2426 	if (sinit.sinit_max_instreams)
2427 		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
2428 	if (sinit.sinit_max_attempts)
2429 		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
2430 	if (sinit.sinit_max_init_timeo)
2431 		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
2432 
2433 	return 0;
2434 }
2435 
2436 /*
2437  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
2438  *
2439  *   Applications that wish to use the sendto() system call may wish to
2440  *   specify a default set of parameters that would normally be supplied
2441  *   through the inclusion of ancillary data.  This socket option allows
2442  *   such an application to set the default sctp_sndrcvinfo structure.
2443  *   The application that wishes to use this socket option simply passes
2444  *   in to this call the sctp_sndrcvinfo structure defined in Section
2445  *   5.2.2) The input parameters accepted by this call include
2446  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
2447  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
2448  *   to this call if the caller is using the UDP model.
2449  */
2450 static int sctp_setsockopt_default_send_param(struct sock *sk,
2451 						char __user *optval, int optlen)
2452 {
2453 	struct sctp_sndrcvinfo info;
2454 	struct sctp_association *asoc;
2455 	struct sctp_sock *sp = sctp_sk(sk);
2456 
2457 	if (optlen != sizeof(struct sctp_sndrcvinfo))
2458 		return -EINVAL;
2459 	if (copy_from_user(&info, optval, optlen))
2460 		return -EFAULT;
2461 
2462 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
2463 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
2464 		return -EINVAL;
2465 
2466 	if (asoc) {
2467 		asoc->default_stream = info.sinfo_stream;
2468 		asoc->default_flags = info.sinfo_flags;
2469 		asoc->default_ppid = info.sinfo_ppid;
2470 		asoc->default_context = info.sinfo_context;
2471 		asoc->default_timetolive = info.sinfo_timetolive;
2472 	} else {
2473 		sp->default_stream = info.sinfo_stream;
2474 		sp->default_flags = info.sinfo_flags;
2475 		sp->default_ppid = info.sinfo_ppid;
2476 		sp->default_context = info.sinfo_context;
2477 		sp->default_timetolive = info.sinfo_timetolive;
2478 	}
2479 
2480 	return 0;
2481 }
2482 
2483 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
2484  *
2485  * Requests that the local SCTP stack use the enclosed peer address as
2486  * the association primary.  The enclosed address must be one of the
2487  * association peer's addresses.
2488  */
2489 static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
2490 					int optlen)
2491 {
2492 	struct sctp_prim prim;
2493 	struct sctp_transport *trans;
2494 
2495 	if (optlen != sizeof(struct sctp_prim))
2496 		return -EINVAL;
2497 
2498 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
2499 		return -EFAULT;
2500 
2501 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
2502 	if (!trans)
2503 		return -EINVAL;
2504 
2505 	sctp_assoc_set_primary(trans->asoc, trans);
2506 
2507 	return 0;
2508 }
2509 
2510 /*
2511  * 7.1.5 SCTP_NODELAY
2512  *
2513  * Turn on/off any Nagle-like algorithm.  This means that packets are
2514  * generally sent as soon as possible and no unnecessary delays are
2515  * introduced, at the cost of more packets in the network.  Expects an
2516  *  integer boolean flag.
2517  */
2518 static int sctp_setsockopt_nodelay(struct sock *sk, char __user *optval,
2519 					int optlen)
2520 {
2521 	int val;
2522 
2523 	if (optlen < sizeof(int))
2524 		return -EINVAL;
2525 	if (get_user(val, (int __user *)optval))
2526 		return -EFAULT;
2527 
2528 	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
2529 	return 0;
2530 }
2531 
2532 /*
2533  *
2534  * 7.1.1 SCTP_RTOINFO
2535  *
2536  * The protocol parameters used to initialize and bound retransmission
2537  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
2538  * and modify these parameters.
2539  * All parameters are time values, in milliseconds.  A value of 0, when
2540  * modifying the parameters, indicates that the current value should not
2541  * be changed.
2542  *
2543  */
2544 static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, int optlen) {
2545 	struct sctp_rtoinfo rtoinfo;
2546 	struct sctp_association *asoc;
2547 
2548 	if (optlen != sizeof (struct sctp_rtoinfo))
2549 		return -EINVAL;
2550 
2551 	if (copy_from_user(&rtoinfo, optval, optlen))
2552 		return -EFAULT;
2553 
2554 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
2555 
2556 	/* Set the values to the specific association */
2557 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
2558 		return -EINVAL;
2559 
2560 	if (asoc) {
2561 		if (rtoinfo.srto_initial != 0)
2562 			asoc->rto_initial =
2563 				msecs_to_jiffies(rtoinfo.srto_initial);
2564 		if (rtoinfo.srto_max != 0)
2565 			asoc->rto_max = msecs_to_jiffies(rtoinfo.srto_max);
2566 		if (rtoinfo.srto_min != 0)
2567 			asoc->rto_min = msecs_to_jiffies(rtoinfo.srto_min);
2568 	} else {
2569 		/* If there is no association or the association-id = 0
2570 		 * set the values to the endpoint.
2571 		 */
2572 		struct sctp_sock *sp = sctp_sk(sk);
2573 
2574 		if (rtoinfo.srto_initial != 0)
2575 			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
2576 		if (rtoinfo.srto_max != 0)
2577 			sp->rtoinfo.srto_max = rtoinfo.srto_max;
2578 		if (rtoinfo.srto_min != 0)
2579 			sp->rtoinfo.srto_min = rtoinfo.srto_min;
2580 	}
2581 
2582 	return 0;
2583 }
2584 
2585 /*
2586  *
2587  * 7.1.2 SCTP_ASSOCINFO
2588  *
2589  * This option is used to tune the the maximum retransmission attempts
2590  * of the association.
2591  * Returns an error if the new association retransmission value is
2592  * greater than the sum of the retransmission value  of the peer.
2593  * See [SCTP] for more information.
2594  *
2595  */
2596 static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, int optlen)
2597 {
2598 
2599 	struct sctp_assocparams assocparams;
2600 	struct sctp_association *asoc;
2601 
2602 	if (optlen != sizeof(struct sctp_assocparams))
2603 		return -EINVAL;
2604 	if (copy_from_user(&assocparams, optval, optlen))
2605 		return -EFAULT;
2606 
2607 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
2608 
2609 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
2610 		return -EINVAL;
2611 
2612 	/* Set the values to the specific association */
2613 	if (asoc) {
2614 		if (assocparams.sasoc_asocmaxrxt != 0) {
2615 			__u32 path_sum = 0;
2616 			int   paths = 0;
2617 			struct list_head *pos;
2618 			struct sctp_transport *peer_addr;
2619 
2620 			list_for_each(pos, &asoc->peer.transport_addr_list) {
2621 				peer_addr = list_entry(pos,
2622 						struct sctp_transport,
2623 						transports);
2624 				path_sum += peer_addr->pathmaxrxt;
2625 				paths++;
2626 			}
2627 
2628 			/* Only validate asocmaxrxt if we have more then
2629 			 * one path/transport.  We do this because path
2630 			 * retransmissions are only counted when we have more
2631 			 * then one path.
2632 			 */
2633 			if (paths > 1 &&
2634 			    assocparams.sasoc_asocmaxrxt > path_sum)
2635 				return -EINVAL;
2636 
2637 			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
2638 		}
2639 
2640 		if (assocparams.sasoc_cookie_life != 0) {
2641 			asoc->cookie_life.tv_sec =
2642 					assocparams.sasoc_cookie_life / 1000;
2643 			asoc->cookie_life.tv_usec =
2644 					(assocparams.sasoc_cookie_life % 1000)
2645 					* 1000;
2646 		}
2647 	} else {
2648 		/* Set the values to the endpoint */
2649 		struct sctp_sock *sp = sctp_sk(sk);
2650 
2651 		if (assocparams.sasoc_asocmaxrxt != 0)
2652 			sp->assocparams.sasoc_asocmaxrxt =
2653 						assocparams.sasoc_asocmaxrxt;
2654 		if (assocparams.sasoc_cookie_life != 0)
2655 			sp->assocparams.sasoc_cookie_life =
2656 						assocparams.sasoc_cookie_life;
2657 	}
2658 	return 0;
2659 }
2660 
2661 /*
2662  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
2663  *
2664  * This socket option is a boolean flag which turns on or off mapped V4
2665  * addresses.  If this option is turned on and the socket is type
2666  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
2667  * If this option is turned off, then no mapping will be done of V4
2668  * addresses and a user will receive both PF_INET6 and PF_INET type
2669  * addresses on the socket.
2670  */
2671 static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, int optlen)
2672 {
2673 	int val;
2674 	struct sctp_sock *sp = sctp_sk(sk);
2675 
2676 	if (optlen < sizeof(int))
2677 		return -EINVAL;
2678 	if (get_user(val, (int __user *)optval))
2679 		return -EFAULT;
2680 	if (val)
2681 		sp->v4mapped = 1;
2682 	else
2683 		sp->v4mapped = 0;
2684 
2685 	return 0;
2686 }
2687 
2688 /*
2689  * 7.1.17 Set the maximum fragrmentation size (SCTP_MAXSEG)
2690  *
2691  * This socket option specifies the maximum size to put in any outgoing
2692  * SCTP chunk.  If a message is larger than this size it will be
2693  * fragmented by SCTP into the specified size.  Note that the underlying
2694  * SCTP implementation may fragment into smaller sized chunks when the
2695  * PMTU of the underlying association is smaller than the value set by
2696  * the user.
2697  */
2698 static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, int optlen)
2699 {
2700 	struct sctp_association *asoc;
2701 	struct list_head *pos;
2702 	struct sctp_sock *sp = sctp_sk(sk);
2703 	int val;
2704 
2705 	if (optlen < sizeof(int))
2706 		return -EINVAL;
2707 	if (get_user(val, (int __user *)optval))
2708 		return -EFAULT;
2709 	if ((val != 0) && ((val < 8) || (val > SCTP_MAX_CHUNK_LEN)))
2710 		return -EINVAL;
2711 	sp->user_frag = val;
2712 
2713 	/* Update the frag_point of the existing associations. */
2714 	list_for_each(pos, &(sp->ep->asocs)) {
2715 		asoc = list_entry(pos, struct sctp_association, asocs);
2716 		asoc->frag_point = sctp_frag_point(sp, asoc->pathmtu);
2717 	}
2718 
2719 	return 0;
2720 }
2721 
2722 
2723 /*
2724  *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
2725  *
2726  *   Requests that the peer mark the enclosed address as the association
2727  *   primary. The enclosed address must be one of the association's
2728  *   locally bound addresses. The following structure is used to make a
2729  *   set primary request:
2730  */
2731 static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
2732 					     int optlen)
2733 {
2734 	struct sctp_sock	*sp;
2735 	struct sctp_endpoint	*ep;
2736 	struct sctp_association	*asoc = NULL;
2737 	struct sctp_setpeerprim	prim;
2738 	struct sctp_chunk	*chunk;
2739 	int 			err;
2740 
2741 	sp = sctp_sk(sk);
2742 	ep = sp->ep;
2743 
2744 	if (!sctp_addip_enable)
2745 		return -EPERM;
2746 
2747 	if (optlen != sizeof(struct sctp_setpeerprim))
2748 		return -EINVAL;
2749 
2750 	if (copy_from_user(&prim, optval, optlen))
2751 		return -EFAULT;
2752 
2753 	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
2754 	if (!asoc)
2755 		return -EINVAL;
2756 
2757 	if (!asoc->peer.asconf_capable)
2758 		return -EPERM;
2759 
2760 	if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
2761 		return -EPERM;
2762 
2763 	if (!sctp_state(asoc, ESTABLISHED))
2764 		return -ENOTCONN;
2765 
2766 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
2767 		return -EADDRNOTAVAIL;
2768 
2769 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
2770 	chunk = sctp_make_asconf_set_prim(asoc,
2771 					  (union sctp_addr *)&prim.sspp_addr);
2772 	if (!chunk)
2773 		return -ENOMEM;
2774 
2775 	err = sctp_send_asconf(asoc, chunk);
2776 
2777 	SCTP_DEBUG_PRINTK("We set peer primary addr primitively.\n");
2778 
2779 	return err;
2780 }
2781 
2782 static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
2783 					  int optlen)
2784 {
2785 	struct sctp_setadaptation adaptation;
2786 
2787 	if (optlen != sizeof(struct sctp_setadaptation))
2788 		return -EINVAL;
2789 	if (copy_from_user(&adaptation, optval, optlen))
2790 		return -EFAULT;
2791 
2792 	sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
2793 
2794 	return 0;
2795 }
2796 
2797 /*
2798  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
2799  *
2800  * The context field in the sctp_sndrcvinfo structure is normally only
2801  * used when a failed message is retrieved holding the value that was
2802  * sent down on the actual send call.  This option allows the setting of
2803  * a default context on an association basis that will be received on
2804  * reading messages from the peer.  This is especially helpful in the
2805  * one-2-many model for an application to keep some reference to an
2806  * internal state machine that is processing messages on the
2807  * association.  Note that the setting of this value only effects
2808  * received messages from the peer and does not effect the value that is
2809  * saved with outbound messages.
2810  */
2811 static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
2812 				   int optlen)
2813 {
2814 	struct sctp_assoc_value params;
2815 	struct sctp_sock *sp;
2816 	struct sctp_association *asoc;
2817 
2818 	if (optlen != sizeof(struct sctp_assoc_value))
2819 		return -EINVAL;
2820 	if (copy_from_user(&params, optval, optlen))
2821 		return -EFAULT;
2822 
2823 	sp = sctp_sk(sk);
2824 
2825 	if (params.assoc_id != 0) {
2826 		asoc = sctp_id2assoc(sk, params.assoc_id);
2827 		if (!asoc)
2828 			return -EINVAL;
2829 		asoc->default_rcv_context = params.assoc_value;
2830 	} else {
2831 		sp->default_rcv_context = params.assoc_value;
2832 	}
2833 
2834 	return 0;
2835 }
2836 
2837 /*
2838  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
2839  *
2840  * This options will at a minimum specify if the implementation is doing
2841  * fragmented interleave.  Fragmented interleave, for a one to many
2842  * socket, is when subsequent calls to receive a message may return
2843  * parts of messages from different associations.  Some implementations
2844  * may allow you to turn this value on or off.  If so, when turned off,
2845  * no fragment interleave will occur (which will cause a head of line
2846  * blocking amongst multiple associations sharing the same one to many
2847  * socket).  When this option is turned on, then each receive call may
2848  * come from a different association (thus the user must receive data
2849  * with the extended calls (e.g. sctp_recvmsg) to keep track of which
2850  * association each receive belongs to.
2851  *
2852  * This option takes a boolean value.  A non-zero value indicates that
2853  * fragmented interleave is on.  A value of zero indicates that
2854  * fragmented interleave is off.
2855  *
2856  * Note that it is important that an implementation that allows this
2857  * option to be turned on, have it off by default.  Otherwise an unaware
2858  * application using the one to many model may become confused and act
2859  * incorrectly.
2860  */
2861 static int sctp_setsockopt_fragment_interleave(struct sock *sk,
2862 					       char __user *optval,
2863 					       int optlen)
2864 {
2865 	int val;
2866 
2867 	if (optlen != sizeof(int))
2868 		return -EINVAL;
2869 	if (get_user(val, (int __user *)optval))
2870 		return -EFAULT;
2871 
2872 	sctp_sk(sk)->frag_interleave = (val == 0) ? 0 : 1;
2873 
2874 	return 0;
2875 }
2876 
2877 /*
2878  * 7.1.25.  Set or Get the sctp partial delivery point
2879  *       (SCTP_PARTIAL_DELIVERY_POINT)
2880  * This option will set or get the SCTP partial delivery point.  This
2881  * point is the size of a message where the partial delivery API will be
2882  * invoked to help free up rwnd space for the peer.  Setting this to a
2883  * lower value will cause partial delivery's to happen more often.  The
2884  * calls argument is an integer that sets or gets the partial delivery
2885  * point.
2886  */
2887 static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
2888 						  char __user *optval,
2889 						  int optlen)
2890 {
2891 	u32 val;
2892 
2893 	if (optlen != sizeof(u32))
2894 		return -EINVAL;
2895 	if (get_user(val, (int __user *)optval))
2896 		return -EFAULT;
2897 
2898 	sctp_sk(sk)->pd_point = val;
2899 
2900 	return 0; /* is this the right error code? */
2901 }
2902 
2903 /*
2904  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
2905  *
2906  * This option will allow a user to change the maximum burst of packets
2907  * that can be emitted by this association.  Note that the default value
2908  * is 4, and some implementations may restrict this setting so that it
2909  * can only be lowered.
2910  *
2911  * NOTE: This text doesn't seem right.  Do this on a socket basis with
2912  * future associations inheriting the socket value.
2913  */
2914 static int sctp_setsockopt_maxburst(struct sock *sk,
2915 				    char __user *optval,
2916 				    int optlen)
2917 {
2918 	int val;
2919 
2920 	if (optlen != sizeof(int))
2921 		return -EINVAL;
2922 	if (get_user(val, (int __user *)optval))
2923 		return -EFAULT;
2924 
2925 	if (val < 0)
2926 		return -EINVAL;
2927 
2928 	sctp_sk(sk)->max_burst = val;
2929 
2930 	return 0;
2931 }
2932 
2933 /* API 6.2 setsockopt(), getsockopt()
2934  *
2935  * Applications use setsockopt() and getsockopt() to set or retrieve
2936  * socket options.  Socket options are used to change the default
2937  * behavior of sockets calls.  They are described in Section 7.
2938  *
2939  * The syntax is:
2940  *
2941  *   ret = getsockopt(int sd, int level, int optname, void __user *optval,
2942  *                    int __user *optlen);
2943  *   ret = setsockopt(int sd, int level, int optname, const void __user *optval,
2944  *                    int optlen);
2945  *
2946  *   sd      - the socket descript.
2947  *   level   - set to IPPROTO_SCTP for all SCTP options.
2948  *   optname - the option name.
2949  *   optval  - the buffer to store the value of the option.
2950  *   optlen  - the size of the buffer.
2951  */
2952 SCTP_STATIC int sctp_setsockopt(struct sock *sk, int level, int optname,
2953 				char __user *optval, int optlen)
2954 {
2955 	int retval = 0;
2956 
2957 	SCTP_DEBUG_PRINTK("sctp_setsockopt(sk: %p... optname: %d)\n",
2958 			  sk, optname);
2959 
2960 	/* I can hardly begin to describe how wrong this is.  This is
2961 	 * so broken as to be worse than useless.  The API draft
2962 	 * REALLY is NOT helpful here...  I am not convinced that the
2963 	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
2964 	 * are at all well-founded.
2965 	 */
2966 	if (level != SOL_SCTP) {
2967 		struct sctp_af *af = sctp_sk(sk)->pf->af;
2968 		retval = af->setsockopt(sk, level, optname, optval, optlen);
2969 		goto out_nounlock;
2970 	}
2971 
2972 	sctp_lock_sock(sk);
2973 
2974 	switch (optname) {
2975 	case SCTP_SOCKOPT_BINDX_ADD:
2976 		/* 'optlen' is the size of the addresses buffer. */
2977 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
2978 					       optlen, SCTP_BINDX_ADD_ADDR);
2979 		break;
2980 
2981 	case SCTP_SOCKOPT_BINDX_REM:
2982 		/* 'optlen' is the size of the addresses buffer. */
2983 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
2984 					       optlen, SCTP_BINDX_REM_ADDR);
2985 		break;
2986 
2987 	case SCTP_SOCKOPT_CONNECTX:
2988 		/* 'optlen' is the size of the addresses buffer. */
2989 		retval = sctp_setsockopt_connectx(sk, (struct sockaddr __user *)optval,
2990 					       optlen);
2991 		break;
2992 
2993 	case SCTP_DISABLE_FRAGMENTS:
2994 		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
2995 		break;
2996 
2997 	case SCTP_EVENTS:
2998 		retval = sctp_setsockopt_events(sk, optval, optlen);
2999 		break;
3000 
3001 	case SCTP_AUTOCLOSE:
3002 		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
3003 		break;
3004 
3005 	case SCTP_PEER_ADDR_PARAMS:
3006 		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
3007 		break;
3008 
3009 	case SCTP_DELAYED_ACK_TIME:
3010 		retval = sctp_setsockopt_delayed_ack_time(sk, optval, optlen);
3011 		break;
3012 	case SCTP_PARTIAL_DELIVERY_POINT:
3013 		retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
3014 		break;
3015 
3016 	case SCTP_INITMSG:
3017 		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
3018 		break;
3019 	case SCTP_DEFAULT_SEND_PARAM:
3020 		retval = sctp_setsockopt_default_send_param(sk, optval,
3021 							    optlen);
3022 		break;
3023 	case SCTP_PRIMARY_ADDR:
3024 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
3025 		break;
3026 	case SCTP_SET_PEER_PRIMARY_ADDR:
3027 		retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
3028 		break;
3029 	case SCTP_NODELAY:
3030 		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
3031 		break;
3032 	case SCTP_RTOINFO:
3033 		retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
3034 		break;
3035 	case SCTP_ASSOCINFO:
3036 		retval = sctp_setsockopt_associnfo(sk, optval, optlen);
3037 		break;
3038 	case SCTP_I_WANT_MAPPED_V4_ADDR:
3039 		retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
3040 		break;
3041 	case SCTP_MAXSEG:
3042 		retval = sctp_setsockopt_maxseg(sk, optval, optlen);
3043 		break;
3044 	case SCTP_ADAPTATION_LAYER:
3045 		retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
3046 		break;
3047 	case SCTP_CONTEXT:
3048 		retval = sctp_setsockopt_context(sk, optval, optlen);
3049 		break;
3050 	case SCTP_FRAGMENT_INTERLEAVE:
3051 		retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
3052 		break;
3053 	case SCTP_MAX_BURST:
3054 		retval = sctp_setsockopt_maxburst(sk, optval, optlen);
3055 		break;
3056 	default:
3057 		retval = -ENOPROTOOPT;
3058 		break;
3059 	}
3060 
3061 	sctp_release_sock(sk);
3062 
3063 out_nounlock:
3064 	return retval;
3065 }
3066 
3067 /* API 3.1.6 connect() - UDP Style Syntax
3068  *
3069  * An application may use the connect() call in the UDP model to initiate an
3070  * association without sending data.
3071  *
3072  * The syntax is:
3073  *
3074  * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
3075  *
3076  * sd: the socket descriptor to have a new association added to.
3077  *
3078  * nam: the address structure (either struct sockaddr_in or struct
3079  *    sockaddr_in6 defined in RFC2553 [7]).
3080  *
3081  * len: the size of the address.
3082  */
3083 SCTP_STATIC int sctp_connect(struct sock *sk, struct sockaddr *addr,
3084 			     int addr_len)
3085 {
3086 	int err = 0;
3087 	struct sctp_af *af;
3088 
3089 	sctp_lock_sock(sk);
3090 
3091 	SCTP_DEBUG_PRINTK("%s - sk: %p, sockaddr: %p, addr_len: %d\n",
3092 			  __FUNCTION__, sk, addr, addr_len);
3093 
3094 	/* Validate addr_len before calling common connect/connectx routine. */
3095 	af = sctp_get_af_specific(addr->sa_family);
3096 	if (!af || addr_len < af->sockaddr_len) {
3097 		err = -EINVAL;
3098 	} else {
3099 		/* Pass correct addr len to common routine (so it knows there
3100 		 * is only one address being passed.
3101 		 */
3102 		err = __sctp_connect(sk, addr, af->sockaddr_len);
3103 	}
3104 
3105 	sctp_release_sock(sk);
3106 	return err;
3107 }
3108 
3109 /* FIXME: Write comments. */
3110 SCTP_STATIC int sctp_disconnect(struct sock *sk, int flags)
3111 {
3112 	return -EOPNOTSUPP; /* STUB */
3113 }
3114 
3115 /* 4.1.4 accept() - TCP Style Syntax
3116  *
3117  * Applications use accept() call to remove an established SCTP
3118  * association from the accept queue of the endpoint.  A new socket
3119  * descriptor will be returned from accept() to represent the newly
3120  * formed association.
3121  */
3122 SCTP_STATIC struct sock *sctp_accept(struct sock *sk, int flags, int *err)
3123 {
3124 	struct sctp_sock *sp;
3125 	struct sctp_endpoint *ep;
3126 	struct sock *newsk = NULL;
3127 	struct sctp_association *asoc;
3128 	long timeo;
3129 	int error = 0;
3130 
3131 	sctp_lock_sock(sk);
3132 
3133 	sp = sctp_sk(sk);
3134 	ep = sp->ep;
3135 
3136 	if (!sctp_style(sk, TCP)) {
3137 		error = -EOPNOTSUPP;
3138 		goto out;
3139 	}
3140 
3141 	if (!sctp_sstate(sk, LISTENING)) {
3142 		error = -EINVAL;
3143 		goto out;
3144 	}
3145 
3146 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
3147 
3148 	error = sctp_wait_for_accept(sk, timeo);
3149 	if (error)
3150 		goto out;
3151 
3152 	/* We treat the list of associations on the endpoint as the accept
3153 	 * queue and pick the first association on the list.
3154 	 */
3155 	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
3156 
3157 	newsk = sp->pf->create_accept_sk(sk, asoc);
3158 	if (!newsk) {
3159 		error = -ENOMEM;
3160 		goto out;
3161 	}
3162 
3163 	/* Populate the fields of the newsk from the oldsk and migrate the
3164 	 * asoc to the newsk.
3165 	 */
3166 	sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
3167 
3168 out:
3169 	sctp_release_sock(sk);
3170 	*err = error;
3171 	return newsk;
3172 }
3173 
3174 /* The SCTP ioctl handler. */
3175 SCTP_STATIC int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
3176 {
3177 	return -ENOIOCTLCMD;
3178 }
3179 
3180 /* This is the function which gets called during socket creation to
3181  * initialized the SCTP-specific portion of the sock.
3182  * The sock structure should already be zero-filled memory.
3183  */
3184 SCTP_STATIC int sctp_init_sock(struct sock *sk)
3185 {
3186 	struct sctp_endpoint *ep;
3187 	struct sctp_sock *sp;
3188 
3189 	SCTP_DEBUG_PRINTK("sctp_init_sock(sk: %p)\n", sk);
3190 
3191 	sp = sctp_sk(sk);
3192 
3193 	/* Initialize the SCTP per socket area.  */
3194 	switch (sk->sk_type) {
3195 	case SOCK_SEQPACKET:
3196 		sp->type = SCTP_SOCKET_UDP;
3197 		break;
3198 	case SOCK_STREAM:
3199 		sp->type = SCTP_SOCKET_TCP;
3200 		break;
3201 	default:
3202 		return -ESOCKTNOSUPPORT;
3203 	}
3204 
3205 	/* Initialize default send parameters. These parameters can be
3206 	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
3207 	 */
3208 	sp->default_stream = 0;
3209 	sp->default_ppid = 0;
3210 	sp->default_flags = 0;
3211 	sp->default_context = 0;
3212 	sp->default_timetolive = 0;
3213 
3214 	sp->default_rcv_context = 0;
3215 	sp->max_burst = sctp_max_burst;
3216 
3217 	/* Initialize default setup parameters. These parameters
3218 	 * can be modified with the SCTP_INITMSG socket option or
3219 	 * overridden by the SCTP_INIT CMSG.
3220 	 */
3221 	sp->initmsg.sinit_num_ostreams   = sctp_max_outstreams;
3222 	sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
3223 	sp->initmsg.sinit_max_attempts   = sctp_max_retrans_init;
3224 	sp->initmsg.sinit_max_init_timeo = sctp_rto_max;
3225 
3226 	/* Initialize default RTO related parameters.  These parameters can
3227 	 * be modified for with the SCTP_RTOINFO socket option.
3228 	 */
3229 	sp->rtoinfo.srto_initial = sctp_rto_initial;
3230 	sp->rtoinfo.srto_max     = sctp_rto_max;
3231 	sp->rtoinfo.srto_min     = sctp_rto_min;
3232 
3233 	/* Initialize default association related parameters. These parameters
3234 	 * can be modified with the SCTP_ASSOCINFO socket option.
3235 	 */
3236 	sp->assocparams.sasoc_asocmaxrxt = sctp_max_retrans_association;
3237 	sp->assocparams.sasoc_number_peer_destinations = 0;
3238 	sp->assocparams.sasoc_peer_rwnd = 0;
3239 	sp->assocparams.sasoc_local_rwnd = 0;
3240 	sp->assocparams.sasoc_cookie_life = sctp_valid_cookie_life;
3241 
3242 	/* Initialize default event subscriptions. By default, all the
3243 	 * options are off.
3244 	 */
3245 	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
3246 
3247 	/* Default Peer Address Parameters.  These defaults can
3248 	 * be modified via SCTP_PEER_ADDR_PARAMS
3249 	 */
3250 	sp->hbinterval  = sctp_hb_interval;
3251 	sp->pathmaxrxt  = sctp_max_retrans_path;
3252 	sp->pathmtu     = 0; // allow default discovery
3253 	sp->sackdelay   = sctp_sack_timeout;
3254 	sp->param_flags = SPP_HB_ENABLE |
3255 			  SPP_PMTUD_ENABLE |
3256 			  SPP_SACKDELAY_ENABLE;
3257 
3258 	/* If enabled no SCTP message fragmentation will be performed.
3259 	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
3260 	 */
3261 	sp->disable_fragments = 0;
3262 
3263 	/* Enable Nagle algorithm by default.  */
3264 	sp->nodelay           = 0;
3265 
3266 	/* Enable by default. */
3267 	sp->v4mapped          = 1;
3268 
3269 	/* Auto-close idle associations after the configured
3270 	 * number of seconds.  A value of 0 disables this
3271 	 * feature.  Configure through the SCTP_AUTOCLOSE socket option,
3272 	 * for UDP-style sockets only.
3273 	 */
3274 	sp->autoclose         = 0;
3275 
3276 	/* User specified fragmentation limit. */
3277 	sp->user_frag         = 0;
3278 
3279 	sp->adaptation_ind = 0;
3280 
3281 	sp->pf = sctp_get_pf_specific(sk->sk_family);
3282 
3283 	/* Control variables for partial data delivery. */
3284 	atomic_set(&sp->pd_mode, 0);
3285 	skb_queue_head_init(&sp->pd_lobby);
3286 	sp->frag_interleave = 0;
3287 
3288 	/* Create a per socket endpoint structure.  Even if we
3289 	 * change the data structure relationships, this may still
3290 	 * be useful for storing pre-connect address information.
3291 	 */
3292 	ep = sctp_endpoint_new(sk, GFP_KERNEL);
3293 	if (!ep)
3294 		return -ENOMEM;
3295 
3296 	sp->ep = ep;
3297 	sp->hmac = NULL;
3298 
3299 	SCTP_DBG_OBJCNT_INC(sock);
3300 	return 0;
3301 }
3302 
3303 /* Cleanup any SCTP per socket resources.  */
3304 SCTP_STATIC int sctp_destroy_sock(struct sock *sk)
3305 {
3306 	struct sctp_endpoint *ep;
3307 
3308 	SCTP_DEBUG_PRINTK("sctp_destroy_sock(sk: %p)\n", sk);
3309 
3310 	/* Release our hold on the endpoint. */
3311 	ep = sctp_sk(sk)->ep;
3312 	sctp_endpoint_free(ep);
3313 
3314 	return 0;
3315 }
3316 
3317 /* API 4.1.7 shutdown() - TCP Style Syntax
3318  *     int shutdown(int socket, int how);
3319  *
3320  *     sd      - the socket descriptor of the association to be closed.
3321  *     how     - Specifies the type of shutdown.  The  values  are
3322  *               as follows:
3323  *               SHUT_RD
3324  *                     Disables further receive operations. No SCTP
3325  *                     protocol action is taken.
3326  *               SHUT_WR
3327  *                     Disables further send operations, and initiates
3328  *                     the SCTP shutdown sequence.
3329  *               SHUT_RDWR
3330  *                     Disables further send  and  receive  operations
3331  *                     and initiates the SCTP shutdown sequence.
3332  */
3333 SCTP_STATIC void sctp_shutdown(struct sock *sk, int how)
3334 {
3335 	struct sctp_endpoint *ep;
3336 	struct sctp_association *asoc;
3337 
3338 	if (!sctp_style(sk, TCP))
3339 		return;
3340 
3341 	if (how & SEND_SHUTDOWN) {
3342 		ep = sctp_sk(sk)->ep;
3343 		if (!list_empty(&ep->asocs)) {
3344 			asoc = list_entry(ep->asocs.next,
3345 					  struct sctp_association, asocs);
3346 			sctp_primitive_SHUTDOWN(asoc, NULL);
3347 		}
3348 	}
3349 }
3350 
3351 /* 7.2.1 Association Status (SCTP_STATUS)
3352 
3353  * Applications can retrieve current status information about an
3354  * association, including association state, peer receiver window size,
3355  * number of unacked data chunks, and number of data chunks pending
3356  * receipt.  This information is read-only.
3357  */
3358 static int sctp_getsockopt_sctp_status(struct sock *sk, int len,
3359 				       char __user *optval,
3360 				       int __user *optlen)
3361 {
3362 	struct sctp_status status;
3363 	struct sctp_association *asoc = NULL;
3364 	struct sctp_transport *transport;
3365 	sctp_assoc_t associd;
3366 	int retval = 0;
3367 
3368 	if (len != sizeof(status)) {
3369 		retval = -EINVAL;
3370 		goto out;
3371 	}
3372 
3373 	if (copy_from_user(&status, optval, sizeof(status))) {
3374 		retval = -EFAULT;
3375 		goto out;
3376 	}
3377 
3378 	associd = status.sstat_assoc_id;
3379 	asoc = sctp_id2assoc(sk, associd);
3380 	if (!asoc) {
3381 		retval = -EINVAL;
3382 		goto out;
3383 	}
3384 
3385 	transport = asoc->peer.primary_path;
3386 
3387 	status.sstat_assoc_id = sctp_assoc2id(asoc);
3388 	status.sstat_state = asoc->state;
3389 	status.sstat_rwnd =  asoc->peer.rwnd;
3390 	status.sstat_unackdata = asoc->unack_data;
3391 
3392 	status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
3393 	status.sstat_instrms = asoc->c.sinit_max_instreams;
3394 	status.sstat_outstrms = asoc->c.sinit_num_ostreams;
3395 	status.sstat_fragmentation_point = asoc->frag_point;
3396 	status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3397 	memcpy(&status.sstat_primary.spinfo_address, &transport->ipaddr,
3398 			transport->af_specific->sockaddr_len);
3399 	/* Map ipv4 address into v4-mapped-on-v6 address.  */
3400 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
3401 		(union sctp_addr *)&status.sstat_primary.spinfo_address);
3402 	status.sstat_primary.spinfo_state = transport->state;
3403 	status.sstat_primary.spinfo_cwnd = transport->cwnd;
3404 	status.sstat_primary.spinfo_srtt = transport->srtt;
3405 	status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
3406 	status.sstat_primary.spinfo_mtu = transport->pathmtu;
3407 
3408 	if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
3409 		status.sstat_primary.spinfo_state = SCTP_ACTIVE;
3410 
3411 	if (put_user(len, optlen)) {
3412 		retval = -EFAULT;
3413 		goto out;
3414 	}
3415 
3416 	SCTP_DEBUG_PRINTK("sctp_getsockopt_sctp_status(%d): %d %d %d\n",
3417 			  len, status.sstat_state, status.sstat_rwnd,
3418 			  status.sstat_assoc_id);
3419 
3420 	if (copy_to_user(optval, &status, len)) {
3421 		retval = -EFAULT;
3422 		goto out;
3423 	}
3424 
3425 out:
3426 	return (retval);
3427 }
3428 
3429 
3430 /* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
3431  *
3432  * Applications can retrieve information about a specific peer address
3433  * of an association, including its reachability state, congestion
3434  * window, and retransmission timer values.  This information is
3435  * read-only.
3436  */
3437 static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
3438 					  char __user *optval,
3439 					  int __user *optlen)
3440 {
3441 	struct sctp_paddrinfo pinfo;
3442 	struct sctp_transport *transport;
3443 	int retval = 0;
3444 
3445 	if (len != sizeof(pinfo)) {
3446 		retval = -EINVAL;
3447 		goto out;
3448 	}
3449 
3450 	if (copy_from_user(&pinfo, optval, sizeof(pinfo))) {
3451 		retval = -EFAULT;
3452 		goto out;
3453 	}
3454 
3455 	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
3456 					   pinfo.spinfo_assoc_id);
3457 	if (!transport)
3458 		return -EINVAL;
3459 
3460 	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3461 	pinfo.spinfo_state = transport->state;
3462 	pinfo.spinfo_cwnd = transport->cwnd;
3463 	pinfo.spinfo_srtt = transport->srtt;
3464 	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
3465 	pinfo.spinfo_mtu = transport->pathmtu;
3466 
3467 	if (pinfo.spinfo_state == SCTP_UNKNOWN)
3468 		pinfo.spinfo_state = SCTP_ACTIVE;
3469 
3470 	if (put_user(len, optlen)) {
3471 		retval = -EFAULT;
3472 		goto out;
3473 	}
3474 
3475 	if (copy_to_user(optval, &pinfo, len)) {
3476 		retval = -EFAULT;
3477 		goto out;
3478 	}
3479 
3480 out:
3481 	return (retval);
3482 }
3483 
3484 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
3485  *
3486  * This option is a on/off flag.  If enabled no SCTP message
3487  * fragmentation will be performed.  Instead if a message being sent
3488  * exceeds the current PMTU size, the message will NOT be sent and
3489  * instead a error will be indicated to the user.
3490  */
3491 static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
3492 					char __user *optval, int __user *optlen)
3493 {
3494 	int val;
3495 
3496 	if (len < sizeof(int))
3497 		return -EINVAL;
3498 
3499 	len = sizeof(int);
3500 	val = (sctp_sk(sk)->disable_fragments == 1);
3501 	if (put_user(len, optlen))
3502 		return -EFAULT;
3503 	if (copy_to_user(optval, &val, len))
3504 		return -EFAULT;
3505 	return 0;
3506 }
3507 
3508 /* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
3509  *
3510  * This socket option is used to specify various notifications and
3511  * ancillary data the user wishes to receive.
3512  */
3513 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
3514 				  int __user *optlen)
3515 {
3516 	if (len != sizeof(struct sctp_event_subscribe))
3517 		return -EINVAL;
3518 	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
3519 		return -EFAULT;
3520 	return 0;
3521 }
3522 
3523 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
3524  *
3525  * This socket option is applicable to the UDP-style socket only.  When
3526  * set it will cause associations that are idle for more than the
3527  * specified number of seconds to automatically close.  An association
3528  * being idle is defined an association that has NOT sent or received
3529  * user data.  The special value of '0' indicates that no automatic
3530  * close of any associations should be performed.  The option expects an
3531  * integer defining the number of seconds of idle time before an
3532  * association is closed.
3533  */
3534 static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
3535 {
3536 	/* Applicable to UDP-style socket only */
3537 	if (sctp_style(sk, TCP))
3538 		return -EOPNOTSUPP;
3539 	if (len != sizeof(int))
3540 		return -EINVAL;
3541 	if (copy_to_user(optval, &sctp_sk(sk)->autoclose, len))
3542 		return -EFAULT;
3543 	return 0;
3544 }
3545 
3546 /* Helper routine to branch off an association to a new socket.  */
3547 SCTP_STATIC int sctp_do_peeloff(struct sctp_association *asoc,
3548 				struct socket **sockp)
3549 {
3550 	struct sock *sk = asoc->base.sk;
3551 	struct socket *sock;
3552 	struct inet_sock *inetsk;
3553 	int err = 0;
3554 
3555 	/* An association cannot be branched off from an already peeled-off
3556 	 * socket, nor is this supported for tcp style sockets.
3557 	 */
3558 	if (!sctp_style(sk, UDP))
3559 		return -EINVAL;
3560 
3561 	/* Create a new socket.  */
3562 	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
3563 	if (err < 0)
3564 		return err;
3565 
3566 	/* Populate the fields of the newsk from the oldsk and migrate the
3567 	 * asoc to the newsk.
3568 	 */
3569 	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
3570 
3571 	/* Make peeled-off sockets more like 1-1 accepted sockets.
3572 	 * Set the daddr and initialize id to something more random
3573 	 */
3574 	inetsk = inet_sk(sock->sk);
3575 	inetsk->daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
3576 	inetsk->id = asoc->next_tsn ^ jiffies;
3577 
3578 	*sockp = sock;
3579 
3580 	return err;
3581 }
3582 
3583 static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
3584 {
3585 	sctp_peeloff_arg_t peeloff;
3586 	struct socket *newsock;
3587 	int retval = 0;
3588 	struct sctp_association *asoc;
3589 
3590 	if (len != sizeof(sctp_peeloff_arg_t))
3591 		return -EINVAL;
3592 	if (copy_from_user(&peeloff, optval, len))
3593 		return -EFAULT;
3594 
3595 	asoc = sctp_id2assoc(sk, peeloff.associd);
3596 	if (!asoc) {
3597 		retval = -EINVAL;
3598 		goto out;
3599 	}
3600 
3601 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p\n", __FUNCTION__, sk, asoc);
3602 
3603 	retval = sctp_do_peeloff(asoc, &newsock);
3604 	if (retval < 0)
3605 		goto out;
3606 
3607 	/* Map the socket to an unused fd that can be returned to the user.  */
3608 	retval = sock_map_fd(newsock);
3609 	if (retval < 0) {
3610 		sock_release(newsock);
3611 		goto out;
3612 	}
3613 
3614 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p newsk: %p sd: %d\n",
3615 			  __FUNCTION__, sk, asoc, newsock->sk, retval);
3616 
3617 	/* Return the fd mapped to the new socket.  */
3618 	peeloff.sd = retval;
3619 	if (copy_to_user(optval, &peeloff, len))
3620 		retval = -EFAULT;
3621 
3622 out:
3623 	return retval;
3624 }
3625 
3626 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
3627  *
3628  * Applications can enable or disable heartbeats for any peer address of
3629  * an association, modify an address's heartbeat interval, force a
3630  * heartbeat to be sent immediately, and adjust the address's maximum
3631  * number of retransmissions sent before an address is considered
3632  * unreachable.  The following structure is used to access and modify an
3633  * address's parameters:
3634  *
3635  *  struct sctp_paddrparams {
3636  *     sctp_assoc_t            spp_assoc_id;
3637  *     struct sockaddr_storage spp_address;
3638  *     uint32_t                spp_hbinterval;
3639  *     uint16_t                spp_pathmaxrxt;
3640  *     uint32_t                spp_pathmtu;
3641  *     uint32_t                spp_sackdelay;
3642  *     uint32_t                spp_flags;
3643  * };
3644  *
3645  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
3646  *                     application, and identifies the association for
3647  *                     this query.
3648  *   spp_address     - This specifies which address is of interest.
3649  *   spp_hbinterval  - This contains the value of the heartbeat interval,
3650  *                     in milliseconds.  If a  value of zero
3651  *                     is present in this field then no changes are to
3652  *                     be made to this parameter.
3653  *   spp_pathmaxrxt  - This contains the maximum number of
3654  *                     retransmissions before this address shall be
3655  *                     considered unreachable. If a  value of zero
3656  *                     is present in this field then no changes are to
3657  *                     be made to this parameter.
3658  *   spp_pathmtu     - When Path MTU discovery is disabled the value
3659  *                     specified here will be the "fixed" path mtu.
3660  *                     Note that if the spp_address field is empty
3661  *                     then all associations on this address will
3662  *                     have this fixed path mtu set upon them.
3663  *
3664  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
3665  *                     the number of milliseconds that sacks will be delayed
3666  *                     for. This value will apply to all addresses of an
3667  *                     association if the spp_address field is empty. Note
3668  *                     also, that if delayed sack is enabled and this
3669  *                     value is set to 0, no change is made to the last
3670  *                     recorded delayed sack timer value.
3671  *
3672  *   spp_flags       - These flags are used to control various features
3673  *                     on an association. The flag field may contain
3674  *                     zero or more of the following options.
3675  *
3676  *                     SPP_HB_ENABLE  - Enable heartbeats on the
3677  *                     specified address. Note that if the address
3678  *                     field is empty all addresses for the association
3679  *                     have heartbeats enabled upon them.
3680  *
3681  *                     SPP_HB_DISABLE - Disable heartbeats on the
3682  *                     speicifed address. Note that if the address
3683  *                     field is empty all addresses for the association
3684  *                     will have their heartbeats disabled. Note also
3685  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
3686  *                     mutually exclusive, only one of these two should
3687  *                     be specified. Enabling both fields will have
3688  *                     undetermined results.
3689  *
3690  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
3691  *                     to be made immediately.
3692  *
3693  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
3694  *                     discovery upon the specified address. Note that
3695  *                     if the address feild is empty then all addresses
3696  *                     on the association are effected.
3697  *
3698  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
3699  *                     discovery upon the specified address. Note that
3700  *                     if the address feild is empty then all addresses
3701  *                     on the association are effected. Not also that
3702  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
3703  *                     exclusive. Enabling both will have undetermined
3704  *                     results.
3705  *
3706  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
3707  *                     on delayed sack. The time specified in spp_sackdelay
3708  *                     is used to specify the sack delay for this address. Note
3709  *                     that if spp_address is empty then all addresses will
3710  *                     enable delayed sack and take on the sack delay
3711  *                     value specified in spp_sackdelay.
3712  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
3713  *                     off delayed sack. If the spp_address field is blank then
3714  *                     delayed sack is disabled for the entire association. Note
3715  *                     also that this field is mutually exclusive to
3716  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
3717  *                     results.
3718  */
3719 static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
3720 					    char __user *optval, int __user *optlen)
3721 {
3722 	struct sctp_paddrparams  params;
3723 	struct sctp_transport   *trans = NULL;
3724 	struct sctp_association *asoc = NULL;
3725 	struct sctp_sock        *sp = sctp_sk(sk);
3726 
3727 	if (len != sizeof(struct sctp_paddrparams))
3728 		return -EINVAL;
3729 
3730 	if (copy_from_user(&params, optval, len))
3731 		return -EFAULT;
3732 
3733 	/* If an address other than INADDR_ANY is specified, and
3734 	 * no transport is found, then the request is invalid.
3735 	 */
3736 	if (!sctp_is_any(( union sctp_addr *)&params.spp_address)) {
3737 		trans = sctp_addr_id2transport(sk, &params.spp_address,
3738 					       params.spp_assoc_id);
3739 		if (!trans) {
3740 			SCTP_DEBUG_PRINTK("Failed no transport\n");
3741 			return -EINVAL;
3742 		}
3743 	}
3744 
3745 	/* Get association, if assoc_id != 0 and the socket is a one
3746 	 * to many style socket, and an association was not found, then
3747 	 * the id was invalid.
3748 	 */
3749 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
3750 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
3751 		SCTP_DEBUG_PRINTK("Failed no association\n");
3752 		return -EINVAL;
3753 	}
3754 
3755 	if (trans) {
3756 		/* Fetch transport values. */
3757 		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
3758 		params.spp_pathmtu    = trans->pathmtu;
3759 		params.spp_pathmaxrxt = trans->pathmaxrxt;
3760 		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
3761 
3762 		/*draft-11 doesn't say what to return in spp_flags*/
3763 		params.spp_flags      = trans->param_flags;
3764 	} else if (asoc) {
3765 		/* Fetch association values. */
3766 		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
3767 		params.spp_pathmtu    = asoc->pathmtu;
3768 		params.spp_pathmaxrxt = asoc->pathmaxrxt;
3769 		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
3770 
3771 		/*draft-11 doesn't say what to return in spp_flags*/
3772 		params.spp_flags      = asoc->param_flags;
3773 	} else {
3774 		/* Fetch socket values. */
3775 		params.spp_hbinterval = sp->hbinterval;
3776 		params.spp_pathmtu    = sp->pathmtu;
3777 		params.spp_sackdelay  = sp->sackdelay;
3778 		params.spp_pathmaxrxt = sp->pathmaxrxt;
3779 
3780 		/*draft-11 doesn't say what to return in spp_flags*/
3781 		params.spp_flags      = sp->param_flags;
3782 	}
3783 
3784 	if (copy_to_user(optval, &params, len))
3785 		return -EFAULT;
3786 
3787 	if (put_user(len, optlen))
3788 		return -EFAULT;
3789 
3790 	return 0;
3791 }
3792 
3793 /* 7.1.23. Delayed Ack Timer (SCTP_DELAYED_ACK_TIME)
3794  *
3795  *   This options will get or set the delayed ack timer.  The time is set
3796  *   in milliseconds.  If the assoc_id is 0, then this sets or gets the
3797  *   endpoints default delayed ack timer value.  If the assoc_id field is
3798  *   non-zero, then the set or get effects the specified association.
3799  *
3800  *   struct sctp_assoc_value {
3801  *       sctp_assoc_t            assoc_id;
3802  *       uint32_t                assoc_value;
3803  *   };
3804  *
3805  *     assoc_id    - This parameter, indicates which association the
3806  *                   user is preforming an action upon. Note that if
3807  *                   this field's value is zero then the endpoints
3808  *                   default value is changed (effecting future
3809  *                   associations only).
3810  *
3811  *     assoc_value - This parameter contains the number of milliseconds
3812  *                   that the user is requesting the delayed ACK timer
3813  *                   be set to. Note that this value is defined in
3814  *                   the standard to be between 200 and 500 milliseconds.
3815  *
3816  *                   Note: a value of zero will leave the value alone,
3817  *                   but disable SACK delay. A non-zero value will also
3818  *                   enable SACK delay.
3819  */
3820 static int sctp_getsockopt_delayed_ack_time(struct sock *sk, int len,
3821 					    char __user *optval,
3822 					    int __user *optlen)
3823 {
3824 	struct sctp_assoc_value  params;
3825 	struct sctp_association *asoc = NULL;
3826 	struct sctp_sock        *sp = sctp_sk(sk);
3827 
3828 	if (len != sizeof(struct sctp_assoc_value))
3829 		return - EINVAL;
3830 
3831 	if (copy_from_user(&params, optval, len))
3832 		return -EFAULT;
3833 
3834 	/* Get association, if assoc_id != 0 and the socket is a one
3835 	 * to many style socket, and an association was not found, then
3836 	 * the id was invalid.
3837 	 */
3838 	asoc = sctp_id2assoc(sk, params.assoc_id);
3839 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
3840 		return -EINVAL;
3841 
3842 	if (asoc) {
3843 		/* Fetch association values. */
3844 		if (asoc->param_flags & SPP_SACKDELAY_ENABLE)
3845 			params.assoc_value = jiffies_to_msecs(
3846 				asoc->sackdelay);
3847 		else
3848 			params.assoc_value = 0;
3849 	} else {
3850 		/* Fetch socket values. */
3851 		if (sp->param_flags & SPP_SACKDELAY_ENABLE)
3852 			params.assoc_value  = sp->sackdelay;
3853 		else
3854 			params.assoc_value  = 0;
3855 	}
3856 
3857 	if (copy_to_user(optval, &params, len))
3858 		return -EFAULT;
3859 
3860 	if (put_user(len, optlen))
3861 		return -EFAULT;
3862 
3863 	return 0;
3864 }
3865 
3866 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
3867  *
3868  * Applications can specify protocol parameters for the default association
3869  * initialization.  The option name argument to setsockopt() and getsockopt()
3870  * is SCTP_INITMSG.
3871  *
3872  * Setting initialization parameters is effective only on an unconnected
3873  * socket (for UDP-style sockets only future associations are effected
3874  * by the change).  With TCP-style sockets, this option is inherited by
3875  * sockets derived from a listener socket.
3876  */
3877 static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
3878 {
3879 	if (len != sizeof(struct sctp_initmsg))
3880 		return -EINVAL;
3881 	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
3882 		return -EFAULT;
3883 	return 0;
3884 }
3885 
3886 static int sctp_getsockopt_peer_addrs_num_old(struct sock *sk, int len,
3887 					      char __user *optval,
3888 					      int __user *optlen)
3889 {
3890 	sctp_assoc_t id;
3891 	struct sctp_association *asoc;
3892 	struct list_head *pos;
3893 	int cnt = 0;
3894 
3895 	if (len != sizeof(sctp_assoc_t))
3896 		return -EINVAL;
3897 
3898 	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
3899 		return -EFAULT;
3900 
3901 	/* For UDP-style sockets, id specifies the association to query.  */
3902 	asoc = sctp_id2assoc(sk, id);
3903 	if (!asoc)
3904 		return -EINVAL;
3905 
3906 	list_for_each(pos, &asoc->peer.transport_addr_list) {
3907 		cnt ++;
3908 	}
3909 
3910 	return cnt;
3911 }
3912 
3913 /*
3914  * Old API for getting list of peer addresses. Does not work for 32-bit
3915  * programs running on a 64-bit kernel
3916  */
3917 static int sctp_getsockopt_peer_addrs_old(struct sock *sk, int len,
3918 					  char __user *optval,
3919 					  int __user *optlen)
3920 {
3921 	struct sctp_association *asoc;
3922 	struct list_head *pos;
3923 	int cnt = 0;
3924 	struct sctp_getaddrs_old getaddrs;
3925 	struct sctp_transport *from;
3926 	void __user *to;
3927 	union sctp_addr temp;
3928 	struct sctp_sock *sp = sctp_sk(sk);
3929 	int addrlen;
3930 
3931 	if (len != sizeof(struct sctp_getaddrs_old))
3932 		return -EINVAL;
3933 
3934 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs_old)))
3935 		return -EFAULT;
3936 
3937 	if (getaddrs.addr_num <= 0) return -EINVAL;
3938 
3939 	/* For UDP-style sockets, id specifies the association to query.  */
3940 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
3941 	if (!asoc)
3942 		return -EINVAL;
3943 
3944 	to = (void __user *)getaddrs.addrs;
3945 	list_for_each(pos, &asoc->peer.transport_addr_list) {
3946 		from = list_entry(pos, struct sctp_transport, transports);
3947 		memcpy(&temp, &from->ipaddr, sizeof(temp));
3948 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
3949 		addrlen = sctp_get_af_specific(sk->sk_family)->sockaddr_len;
3950 		if (copy_to_user(to, &temp, addrlen))
3951 			return -EFAULT;
3952 		to += addrlen ;
3953 		cnt ++;
3954 		if (cnt >= getaddrs.addr_num) break;
3955 	}
3956 	getaddrs.addr_num = cnt;
3957 	if (copy_to_user(optval, &getaddrs, sizeof(struct sctp_getaddrs_old)))
3958 		return -EFAULT;
3959 
3960 	return 0;
3961 }
3962 
3963 static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
3964 				      char __user *optval, int __user *optlen)
3965 {
3966 	struct sctp_association *asoc;
3967 	struct list_head *pos;
3968 	int cnt = 0;
3969 	struct sctp_getaddrs getaddrs;
3970 	struct sctp_transport *from;
3971 	void __user *to;
3972 	union sctp_addr temp;
3973 	struct sctp_sock *sp = sctp_sk(sk);
3974 	int addrlen;
3975 	size_t space_left;
3976 	int bytes_copied;
3977 
3978 	if (len < sizeof(struct sctp_getaddrs))
3979 		return -EINVAL;
3980 
3981 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
3982 		return -EFAULT;
3983 
3984 	/* For UDP-style sockets, id specifies the association to query.  */
3985 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
3986 	if (!asoc)
3987 		return -EINVAL;
3988 
3989 	to = optval + offsetof(struct sctp_getaddrs,addrs);
3990 	space_left = len - sizeof(struct sctp_getaddrs) -
3991 			offsetof(struct sctp_getaddrs,addrs);
3992 
3993 	list_for_each(pos, &asoc->peer.transport_addr_list) {
3994 		from = list_entry(pos, struct sctp_transport, transports);
3995 		memcpy(&temp, &from->ipaddr, sizeof(temp));
3996 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
3997 		addrlen = sctp_get_af_specific(sk->sk_family)->sockaddr_len;
3998 		if (space_left < addrlen)
3999 			return -ENOMEM;
4000 		if (copy_to_user(to, &temp, addrlen))
4001 			return -EFAULT;
4002 		to += addrlen;
4003 		cnt++;
4004 		space_left -= addrlen;
4005 	}
4006 
4007 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
4008 		return -EFAULT;
4009 	bytes_copied = ((char __user *)to) - optval;
4010 	if (put_user(bytes_copied, optlen))
4011 		return -EFAULT;
4012 
4013 	return 0;
4014 }
4015 
4016 static int sctp_getsockopt_local_addrs_num_old(struct sock *sk, int len,
4017 					       char __user *optval,
4018 					       int __user *optlen)
4019 {
4020 	sctp_assoc_t id;
4021 	struct sctp_bind_addr *bp;
4022 	struct sctp_association *asoc;
4023 	struct list_head *pos, *temp;
4024 	struct sctp_sockaddr_entry *addr;
4025 	rwlock_t *addr_lock;
4026 	int cnt = 0;
4027 
4028 	if (len != sizeof(sctp_assoc_t))
4029 		return -EINVAL;
4030 
4031 	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
4032 		return -EFAULT;
4033 
4034 	/*
4035 	 *  For UDP-style sockets, id specifies the association to query.
4036 	 *  If the id field is set to the value '0' then the locally bound
4037 	 *  addresses are returned without regard to any particular
4038 	 *  association.
4039 	 */
4040 	if (0 == id) {
4041 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4042 		addr_lock = &sctp_sk(sk)->ep->base.addr_lock;
4043 	} else {
4044 		asoc = sctp_id2assoc(sk, id);
4045 		if (!asoc)
4046 			return -EINVAL;
4047 		bp = &asoc->base.bind_addr;
4048 		addr_lock = &asoc->base.addr_lock;
4049 	}
4050 
4051 	sctp_read_lock(addr_lock);
4052 
4053 	/* If the endpoint is bound to 0.0.0.0 or ::0, count the valid
4054 	 * addresses from the global local address list.
4055 	 */
4056 	if (sctp_list_single_entry(&bp->address_list)) {
4057 		addr = list_entry(bp->address_list.next,
4058 				  struct sctp_sockaddr_entry, list);
4059 		if (sctp_is_any(&addr->a)) {
4060 			list_for_each_safe(pos, temp, &sctp_local_addr_list) {
4061 				addr = list_entry(pos,
4062 						  struct sctp_sockaddr_entry,
4063 						  list);
4064 				if ((PF_INET == sk->sk_family) &&
4065 				    (AF_INET6 == addr->a.sa.sa_family))
4066 					continue;
4067 				cnt++;
4068 			}
4069 		} else {
4070 			cnt = 1;
4071 		}
4072 		goto done;
4073 	}
4074 
4075 	list_for_each(pos, &bp->address_list) {
4076 		cnt ++;
4077 	}
4078 
4079 done:
4080 	sctp_read_unlock(addr_lock);
4081 	return cnt;
4082 }
4083 
4084 /* Helper function that copies local addresses to user and returns the number
4085  * of addresses copied.
4086  */
4087 static int sctp_copy_laddrs_old(struct sock *sk, __u16 port,
4088 					int max_addrs, void *to,
4089 					int *bytes_copied)
4090 {
4091 	struct list_head *pos, *next;
4092 	struct sctp_sockaddr_entry *addr;
4093 	union sctp_addr temp;
4094 	int cnt = 0;
4095 	int addrlen;
4096 
4097 	list_for_each_safe(pos, next, &sctp_local_addr_list) {
4098 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
4099 		if ((PF_INET == sk->sk_family) &&
4100 		    (AF_INET6 == addr->a.sa.sa_family))
4101 			continue;
4102 		memcpy(&temp, &addr->a, sizeof(temp));
4103 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4104 								&temp);
4105 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4106 		memcpy(to, &temp, addrlen);
4107 
4108 		to += addrlen;
4109 		*bytes_copied += addrlen;
4110 		cnt ++;
4111 		if (cnt >= max_addrs) break;
4112 	}
4113 
4114 	return cnt;
4115 }
4116 
4117 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
4118 			    size_t space_left, int *bytes_copied)
4119 {
4120 	struct list_head *pos, *next;
4121 	struct sctp_sockaddr_entry *addr;
4122 	union sctp_addr temp;
4123 	int cnt = 0;
4124 	int addrlen;
4125 
4126 	list_for_each_safe(pos, next, &sctp_local_addr_list) {
4127 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
4128 		if ((PF_INET == sk->sk_family) &&
4129 		    (AF_INET6 == addr->a.sa.sa_family))
4130 			continue;
4131 		memcpy(&temp, &addr->a, sizeof(temp));
4132 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4133 								&temp);
4134 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4135 		if (space_left < addrlen)
4136 			return -ENOMEM;
4137 		memcpy(to, &temp, addrlen);
4138 
4139 		to += addrlen;
4140 		cnt ++;
4141 		space_left -= addrlen;
4142 		bytes_copied += addrlen;
4143 	}
4144 
4145 	return cnt;
4146 }
4147 
4148 /* Old API for getting list of local addresses. Does not work for 32-bit
4149  * programs running on a 64-bit kernel
4150  */
4151 static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
4152 					   char __user *optval, int __user *optlen)
4153 {
4154 	struct sctp_bind_addr *bp;
4155 	struct sctp_association *asoc;
4156 	struct list_head *pos;
4157 	int cnt = 0;
4158 	struct sctp_getaddrs_old getaddrs;
4159 	struct sctp_sockaddr_entry *addr;
4160 	void __user *to;
4161 	union sctp_addr temp;
4162 	struct sctp_sock *sp = sctp_sk(sk);
4163 	int addrlen;
4164 	rwlock_t *addr_lock;
4165 	int err = 0;
4166 	void *addrs;
4167 	int bytes_copied = 0;
4168 
4169 	if (len != sizeof(struct sctp_getaddrs_old))
4170 		return -EINVAL;
4171 
4172 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs_old)))
4173 		return -EFAULT;
4174 
4175 	if (getaddrs.addr_num <= 0) return -EINVAL;
4176 	/*
4177 	 *  For UDP-style sockets, id specifies the association to query.
4178 	 *  If the id field is set to the value '0' then the locally bound
4179 	 *  addresses are returned without regard to any particular
4180 	 *  association.
4181 	 */
4182 	if (0 == getaddrs.assoc_id) {
4183 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4184 		addr_lock = &sctp_sk(sk)->ep->base.addr_lock;
4185 	} else {
4186 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4187 		if (!asoc)
4188 			return -EINVAL;
4189 		bp = &asoc->base.bind_addr;
4190 		addr_lock = &asoc->base.addr_lock;
4191 	}
4192 
4193 	to = getaddrs.addrs;
4194 
4195 	/* Allocate space for a local instance of packed array to hold all
4196 	 * the data.  We store addresses here first and then put write them
4197 	 * to the user in one shot.
4198 	 */
4199 	addrs = kmalloc(sizeof(union sctp_addr) * getaddrs.addr_num,
4200 			GFP_KERNEL);
4201 	if (!addrs)
4202 		return -ENOMEM;
4203 
4204 	sctp_read_lock(addr_lock);
4205 
4206 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4207 	 * addresses from the global local address list.
4208 	 */
4209 	if (sctp_list_single_entry(&bp->address_list)) {
4210 		addr = list_entry(bp->address_list.next,
4211 				  struct sctp_sockaddr_entry, list);
4212 		if (sctp_is_any(&addr->a)) {
4213 			cnt = sctp_copy_laddrs_old(sk, bp->port,
4214 						   getaddrs.addr_num,
4215 						   addrs, &bytes_copied);
4216 			goto copy_getaddrs;
4217 		}
4218 	}
4219 
4220 	list_for_each(pos, &bp->address_list) {
4221 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
4222 		memcpy(&temp, &addr->a, sizeof(temp));
4223 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4224 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4225 		memcpy(addrs, &temp, addrlen);
4226 		to += addrlen;
4227 		bytes_copied += addrlen;
4228 		cnt ++;
4229 		if (cnt >= getaddrs.addr_num) break;
4230 	}
4231 
4232 copy_getaddrs:
4233 	sctp_read_unlock(addr_lock);
4234 
4235 	/* copy the entire address list into the user provided space */
4236 	if (copy_to_user(to, addrs, bytes_copied)) {
4237 		err = -EFAULT;
4238 		goto error;
4239 	}
4240 
4241 	/* copy the leading structure back to user */
4242 	getaddrs.addr_num = cnt;
4243 	if (copy_to_user(optval, &getaddrs, sizeof(struct sctp_getaddrs_old)))
4244 		err = -EFAULT;
4245 
4246 error:
4247 	kfree(addrs);
4248 	return err;
4249 }
4250 
4251 static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
4252 				       char __user *optval, int __user *optlen)
4253 {
4254 	struct sctp_bind_addr *bp;
4255 	struct sctp_association *asoc;
4256 	struct list_head *pos;
4257 	int cnt = 0;
4258 	struct sctp_getaddrs getaddrs;
4259 	struct sctp_sockaddr_entry *addr;
4260 	void __user *to;
4261 	union sctp_addr temp;
4262 	struct sctp_sock *sp = sctp_sk(sk);
4263 	int addrlen;
4264 	rwlock_t *addr_lock;
4265 	int err = 0;
4266 	size_t space_left;
4267 	int bytes_copied = 0;
4268 	void *addrs;
4269 
4270 	if (len <= sizeof(struct sctp_getaddrs))
4271 		return -EINVAL;
4272 
4273 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4274 		return -EFAULT;
4275 
4276 	/*
4277 	 *  For UDP-style sockets, id specifies the association to query.
4278 	 *  If the id field is set to the value '0' then the locally bound
4279 	 *  addresses are returned without regard to any particular
4280 	 *  association.
4281 	 */
4282 	if (0 == getaddrs.assoc_id) {
4283 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4284 		addr_lock = &sctp_sk(sk)->ep->base.addr_lock;
4285 	} else {
4286 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4287 		if (!asoc)
4288 			return -EINVAL;
4289 		bp = &asoc->base.bind_addr;
4290 		addr_lock = &asoc->base.addr_lock;
4291 	}
4292 
4293 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4294 	space_left = len - sizeof(struct sctp_getaddrs) -
4295 			 offsetof(struct sctp_getaddrs,addrs);
4296 	addrs = kmalloc(space_left, GFP_KERNEL);
4297 	if (!addrs)
4298 		return -ENOMEM;
4299 
4300 	sctp_read_lock(addr_lock);
4301 
4302 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4303 	 * addresses from the global local address list.
4304 	 */
4305 	if (sctp_list_single_entry(&bp->address_list)) {
4306 		addr = list_entry(bp->address_list.next,
4307 				  struct sctp_sockaddr_entry, list);
4308 		if (sctp_is_any(&addr->a)) {
4309 			cnt = sctp_copy_laddrs(sk, bp->port, addrs,
4310 						space_left, &bytes_copied);
4311 			if (cnt < 0) {
4312 				err = cnt;
4313 				goto error;
4314 			}
4315 			goto copy_getaddrs;
4316 		}
4317 	}
4318 
4319 	list_for_each(pos, &bp->address_list) {
4320 		addr = list_entry(pos, struct sctp_sockaddr_entry, list);
4321 		memcpy(&temp, &addr->a, sizeof(temp));
4322 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4323 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4324 		if (space_left < addrlen) {
4325 			err =  -ENOMEM; /*fixme: right error?*/
4326 			goto error;
4327 		}
4328 		memcpy(addrs, &temp, addrlen);
4329 		to += addrlen;
4330 		bytes_copied += addrlen;
4331 		cnt ++;
4332 		space_left -= addrlen;
4333 	}
4334 
4335 copy_getaddrs:
4336 	sctp_read_unlock(addr_lock);
4337 
4338 	if (copy_to_user(to, addrs, bytes_copied)) {
4339 		err = -EFAULT;
4340 		goto error;
4341 	}
4342 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
4343 		return -EFAULT;
4344 	if (put_user(bytes_copied, optlen))
4345 		return -EFAULT;
4346 
4347 error:
4348 	kfree(addrs);
4349 	return err;
4350 }
4351 
4352 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
4353  *
4354  * Requests that the local SCTP stack use the enclosed peer address as
4355  * the association primary.  The enclosed address must be one of the
4356  * association peer's addresses.
4357  */
4358 static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
4359 					char __user *optval, int __user *optlen)
4360 {
4361 	struct sctp_prim prim;
4362 	struct sctp_association *asoc;
4363 	struct sctp_sock *sp = sctp_sk(sk);
4364 
4365 	if (len != sizeof(struct sctp_prim))
4366 		return -EINVAL;
4367 
4368 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
4369 		return -EFAULT;
4370 
4371 	asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
4372 	if (!asoc)
4373 		return -EINVAL;
4374 
4375 	if (!asoc->peer.primary_path)
4376 		return -ENOTCONN;
4377 
4378 	memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
4379 		asoc->peer.primary_path->af_specific->sockaddr_len);
4380 
4381 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp,
4382 			(union sctp_addr *)&prim.ssp_addr);
4383 
4384 	if (copy_to_user(optval, &prim, sizeof(struct sctp_prim)))
4385 		return -EFAULT;
4386 
4387 	return 0;
4388 }
4389 
4390 /*
4391  * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
4392  *
4393  * Requests that the local endpoint set the specified Adaptation Layer
4394  * Indication parameter for all future INIT and INIT-ACK exchanges.
4395  */
4396 static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
4397 				  char __user *optval, int __user *optlen)
4398 {
4399 	struct sctp_setadaptation adaptation;
4400 
4401 	if (len != sizeof(struct sctp_setadaptation))
4402 		return -EINVAL;
4403 
4404 	adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
4405 	if (copy_to_user(optval, &adaptation, len))
4406 		return -EFAULT;
4407 
4408 	return 0;
4409 }
4410 
4411 /*
4412  *
4413  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
4414  *
4415  *   Applications that wish to use the sendto() system call may wish to
4416  *   specify a default set of parameters that would normally be supplied
4417  *   through the inclusion of ancillary data.  This socket option allows
4418  *   such an application to set the default sctp_sndrcvinfo structure.
4419 
4420 
4421  *   The application that wishes to use this socket option simply passes
4422  *   in to this call the sctp_sndrcvinfo structure defined in Section
4423  *   5.2.2) The input parameters accepted by this call include
4424  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
4425  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
4426  *   to this call if the caller is using the UDP model.
4427  *
4428  *   For getsockopt, it get the default sctp_sndrcvinfo structure.
4429  */
4430 static int sctp_getsockopt_default_send_param(struct sock *sk,
4431 					int len, char __user *optval,
4432 					int __user *optlen)
4433 {
4434 	struct sctp_sndrcvinfo info;
4435 	struct sctp_association *asoc;
4436 	struct sctp_sock *sp = sctp_sk(sk);
4437 
4438 	if (len != sizeof(struct sctp_sndrcvinfo))
4439 		return -EINVAL;
4440 	if (copy_from_user(&info, optval, sizeof(struct sctp_sndrcvinfo)))
4441 		return -EFAULT;
4442 
4443 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
4444 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
4445 		return -EINVAL;
4446 
4447 	if (asoc) {
4448 		info.sinfo_stream = asoc->default_stream;
4449 		info.sinfo_flags = asoc->default_flags;
4450 		info.sinfo_ppid = asoc->default_ppid;
4451 		info.sinfo_context = asoc->default_context;
4452 		info.sinfo_timetolive = asoc->default_timetolive;
4453 	} else {
4454 		info.sinfo_stream = sp->default_stream;
4455 		info.sinfo_flags = sp->default_flags;
4456 		info.sinfo_ppid = sp->default_ppid;
4457 		info.sinfo_context = sp->default_context;
4458 		info.sinfo_timetolive = sp->default_timetolive;
4459 	}
4460 
4461 	if (copy_to_user(optval, &info, sizeof(struct sctp_sndrcvinfo)))
4462 		return -EFAULT;
4463 
4464 	return 0;
4465 }
4466 
4467 /*
4468  *
4469  * 7.1.5 SCTP_NODELAY
4470  *
4471  * Turn on/off any Nagle-like algorithm.  This means that packets are
4472  * generally sent as soon as possible and no unnecessary delays are
4473  * introduced, at the cost of more packets in the network.  Expects an
4474  * integer boolean flag.
4475  */
4476 
4477 static int sctp_getsockopt_nodelay(struct sock *sk, int len,
4478 				   char __user *optval, int __user *optlen)
4479 {
4480 	int val;
4481 
4482 	if (len < sizeof(int))
4483 		return -EINVAL;
4484 
4485 	len = sizeof(int);
4486 	val = (sctp_sk(sk)->nodelay == 1);
4487 	if (put_user(len, optlen))
4488 		return -EFAULT;
4489 	if (copy_to_user(optval, &val, len))
4490 		return -EFAULT;
4491 	return 0;
4492 }
4493 
4494 /*
4495  *
4496  * 7.1.1 SCTP_RTOINFO
4497  *
4498  * The protocol parameters used to initialize and bound retransmission
4499  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
4500  * and modify these parameters.
4501  * All parameters are time values, in milliseconds.  A value of 0, when
4502  * modifying the parameters, indicates that the current value should not
4503  * be changed.
4504  *
4505  */
4506 static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
4507 				char __user *optval,
4508 				int __user *optlen) {
4509 	struct sctp_rtoinfo rtoinfo;
4510 	struct sctp_association *asoc;
4511 
4512 	if (len != sizeof (struct sctp_rtoinfo))
4513 		return -EINVAL;
4514 
4515 	if (copy_from_user(&rtoinfo, optval, sizeof (struct sctp_rtoinfo)))
4516 		return -EFAULT;
4517 
4518 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
4519 
4520 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
4521 		return -EINVAL;
4522 
4523 	/* Values corresponding to the specific association. */
4524 	if (asoc) {
4525 		rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
4526 		rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
4527 		rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
4528 	} else {
4529 		/* Values corresponding to the endpoint. */
4530 		struct sctp_sock *sp = sctp_sk(sk);
4531 
4532 		rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
4533 		rtoinfo.srto_max = sp->rtoinfo.srto_max;
4534 		rtoinfo.srto_min = sp->rtoinfo.srto_min;
4535 	}
4536 
4537 	if (put_user(len, optlen))
4538 		return -EFAULT;
4539 
4540 	if (copy_to_user(optval, &rtoinfo, len))
4541 		return -EFAULT;
4542 
4543 	return 0;
4544 }
4545 
4546 /*
4547  *
4548  * 7.1.2 SCTP_ASSOCINFO
4549  *
4550  * This option is used to tune the the maximum retransmission attempts
4551  * of the association.
4552  * Returns an error if the new association retransmission value is
4553  * greater than the sum of the retransmission value  of the peer.
4554  * See [SCTP] for more information.
4555  *
4556  */
4557 static int sctp_getsockopt_associnfo(struct sock *sk, int len,
4558 				     char __user *optval,
4559 				     int __user *optlen)
4560 {
4561 
4562 	struct sctp_assocparams assocparams;
4563 	struct sctp_association *asoc;
4564 	struct list_head *pos;
4565 	int cnt = 0;
4566 
4567 	if (len != sizeof (struct sctp_assocparams))
4568 		return -EINVAL;
4569 
4570 	if (copy_from_user(&assocparams, optval,
4571 			sizeof (struct sctp_assocparams)))
4572 		return -EFAULT;
4573 
4574 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
4575 
4576 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
4577 		return -EINVAL;
4578 
4579 	/* Values correspoinding to the specific association */
4580 	if (asoc) {
4581 		assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
4582 		assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
4583 		assocparams.sasoc_local_rwnd = asoc->a_rwnd;
4584 		assocparams.sasoc_cookie_life = (asoc->cookie_life.tv_sec
4585 						* 1000) +
4586 						(asoc->cookie_life.tv_usec
4587 						/ 1000);
4588 
4589 		list_for_each(pos, &asoc->peer.transport_addr_list) {
4590 			cnt ++;
4591 		}
4592 
4593 		assocparams.sasoc_number_peer_destinations = cnt;
4594 	} else {
4595 		/* Values corresponding to the endpoint */
4596 		struct sctp_sock *sp = sctp_sk(sk);
4597 
4598 		assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
4599 		assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
4600 		assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
4601 		assocparams.sasoc_cookie_life =
4602 					sp->assocparams.sasoc_cookie_life;
4603 		assocparams.sasoc_number_peer_destinations =
4604 					sp->assocparams.
4605 					sasoc_number_peer_destinations;
4606 	}
4607 
4608 	if (put_user(len, optlen))
4609 		return -EFAULT;
4610 
4611 	if (copy_to_user(optval, &assocparams, len))
4612 		return -EFAULT;
4613 
4614 	return 0;
4615 }
4616 
4617 /*
4618  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
4619  *
4620  * This socket option is a boolean flag which turns on or off mapped V4
4621  * addresses.  If this option is turned on and the socket is type
4622  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
4623  * If this option is turned off, then no mapping will be done of V4
4624  * addresses and a user will receive both PF_INET6 and PF_INET type
4625  * addresses on the socket.
4626  */
4627 static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
4628 				    char __user *optval, int __user *optlen)
4629 {
4630 	int val;
4631 	struct sctp_sock *sp = sctp_sk(sk);
4632 
4633 	if (len < sizeof(int))
4634 		return -EINVAL;
4635 
4636 	len = sizeof(int);
4637 	val = sp->v4mapped;
4638 	if (put_user(len, optlen))
4639 		return -EFAULT;
4640 	if (copy_to_user(optval, &val, len))
4641 		return -EFAULT;
4642 
4643 	return 0;
4644 }
4645 
4646 /*
4647  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
4648  * (chapter and verse is quoted at sctp_setsockopt_context())
4649  */
4650 static int sctp_getsockopt_context(struct sock *sk, int len,
4651 				   char __user *optval, int __user *optlen)
4652 {
4653 	struct sctp_assoc_value params;
4654 	struct sctp_sock *sp;
4655 	struct sctp_association *asoc;
4656 
4657 	if (len != sizeof(struct sctp_assoc_value))
4658 		return -EINVAL;
4659 
4660 	if (copy_from_user(&params, optval, len))
4661 		return -EFAULT;
4662 
4663 	sp = sctp_sk(sk);
4664 
4665 	if (params.assoc_id != 0) {
4666 		asoc = sctp_id2assoc(sk, params.assoc_id);
4667 		if (!asoc)
4668 			return -EINVAL;
4669 		params.assoc_value = asoc->default_rcv_context;
4670 	} else {
4671 		params.assoc_value = sp->default_rcv_context;
4672 	}
4673 
4674 	if (put_user(len, optlen))
4675 		return -EFAULT;
4676 	if (copy_to_user(optval, &params, len))
4677 		return -EFAULT;
4678 
4679 	return 0;
4680 }
4681 
4682 /*
4683  * 7.1.17 Set the maximum fragrmentation size (SCTP_MAXSEG)
4684  *
4685  * This socket option specifies the maximum size to put in any outgoing
4686  * SCTP chunk.  If a message is larger than this size it will be
4687  * fragmented by SCTP into the specified size.  Note that the underlying
4688  * SCTP implementation may fragment into smaller sized chunks when the
4689  * PMTU of the underlying association is smaller than the value set by
4690  * the user.
4691  */
4692 static int sctp_getsockopt_maxseg(struct sock *sk, int len,
4693 				  char __user *optval, int __user *optlen)
4694 {
4695 	int val;
4696 
4697 	if (len < sizeof(int))
4698 		return -EINVAL;
4699 
4700 	len = sizeof(int);
4701 
4702 	val = sctp_sk(sk)->user_frag;
4703 	if (put_user(len, optlen))
4704 		return -EFAULT;
4705 	if (copy_to_user(optval, &val, len))
4706 		return -EFAULT;
4707 
4708 	return 0;
4709 }
4710 
4711 /*
4712  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
4713  * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
4714  */
4715 static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
4716 					       char __user *optval, int __user *optlen)
4717 {
4718 	int val;
4719 
4720 	if (len < sizeof(int))
4721 		return -EINVAL;
4722 
4723 	len = sizeof(int);
4724 
4725 	val = sctp_sk(sk)->frag_interleave;
4726 	if (put_user(len, optlen))
4727 		return -EFAULT;
4728 	if (copy_to_user(optval, &val, len))
4729 		return -EFAULT;
4730 
4731 	return 0;
4732 }
4733 
4734 /*
4735  * 7.1.25.  Set or Get the sctp partial delivery point
4736  * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
4737  */
4738 static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
4739 						  char __user *optval,
4740 						  int __user *optlen)
4741 {
4742         u32 val;
4743 
4744 	if (len < sizeof(u32))
4745 		return -EINVAL;
4746 
4747 	len = sizeof(u32);
4748 
4749 	val = sctp_sk(sk)->pd_point;
4750 	if (put_user(len, optlen))
4751 		return -EFAULT;
4752 	if (copy_to_user(optval, &val, len))
4753 		return -EFAULT;
4754 
4755 	return -ENOTSUPP;
4756 }
4757 
4758 /*
4759  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
4760  * (chapter and verse is quoted at sctp_setsockopt_maxburst())
4761  */
4762 static int sctp_getsockopt_maxburst(struct sock *sk, int len,
4763 				    char __user *optval,
4764 				    int __user *optlen)
4765 {
4766         int val;
4767 
4768 	if (len < sizeof(int))
4769 		return -EINVAL;
4770 
4771 	len = sizeof(int);
4772 
4773 	val = sctp_sk(sk)->max_burst;
4774 	if (put_user(len, optlen))
4775 		return -EFAULT;
4776 	if (copy_to_user(optval, &val, len))
4777 		return -EFAULT;
4778 
4779 	return -ENOTSUPP;
4780 }
4781 
4782 SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
4783 				char __user *optval, int __user *optlen)
4784 {
4785 	int retval = 0;
4786 	int len;
4787 
4788 	SCTP_DEBUG_PRINTK("sctp_getsockopt(sk: %p... optname: %d)\n",
4789 			  sk, optname);
4790 
4791 	/* I can hardly begin to describe how wrong this is.  This is
4792 	 * so broken as to be worse than useless.  The API draft
4793 	 * REALLY is NOT helpful here...  I am not convinced that the
4794 	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
4795 	 * are at all well-founded.
4796 	 */
4797 	if (level != SOL_SCTP) {
4798 		struct sctp_af *af = sctp_sk(sk)->pf->af;
4799 
4800 		retval = af->getsockopt(sk, level, optname, optval, optlen);
4801 		return retval;
4802 	}
4803 
4804 	if (get_user(len, optlen))
4805 		return -EFAULT;
4806 
4807 	sctp_lock_sock(sk);
4808 
4809 	switch (optname) {
4810 	case SCTP_STATUS:
4811 		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
4812 		break;
4813 	case SCTP_DISABLE_FRAGMENTS:
4814 		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
4815 							   optlen);
4816 		break;
4817 	case SCTP_EVENTS:
4818 		retval = sctp_getsockopt_events(sk, len, optval, optlen);
4819 		break;
4820 	case SCTP_AUTOCLOSE:
4821 		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
4822 		break;
4823 	case SCTP_SOCKOPT_PEELOFF:
4824 		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
4825 		break;
4826 	case SCTP_PEER_ADDR_PARAMS:
4827 		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
4828 							  optlen);
4829 		break;
4830 	case SCTP_DELAYED_ACK_TIME:
4831 		retval = sctp_getsockopt_delayed_ack_time(sk, len, optval,
4832 							  optlen);
4833 		break;
4834 	case SCTP_INITMSG:
4835 		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
4836 		break;
4837 	case SCTP_GET_PEER_ADDRS_NUM_OLD:
4838 		retval = sctp_getsockopt_peer_addrs_num_old(sk, len, optval,
4839 							    optlen);
4840 		break;
4841 	case SCTP_GET_LOCAL_ADDRS_NUM_OLD:
4842 		retval = sctp_getsockopt_local_addrs_num_old(sk, len, optval,
4843 							     optlen);
4844 		break;
4845 	case SCTP_GET_PEER_ADDRS_OLD:
4846 		retval = sctp_getsockopt_peer_addrs_old(sk, len, optval,
4847 							optlen);
4848 		break;
4849 	case SCTP_GET_LOCAL_ADDRS_OLD:
4850 		retval = sctp_getsockopt_local_addrs_old(sk, len, optval,
4851 							 optlen);
4852 		break;
4853 	case SCTP_GET_PEER_ADDRS:
4854 		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
4855 						    optlen);
4856 		break;
4857 	case SCTP_GET_LOCAL_ADDRS:
4858 		retval = sctp_getsockopt_local_addrs(sk, len, optval,
4859 						     optlen);
4860 		break;
4861 	case SCTP_DEFAULT_SEND_PARAM:
4862 		retval = sctp_getsockopt_default_send_param(sk, len,
4863 							    optval, optlen);
4864 		break;
4865 	case SCTP_PRIMARY_ADDR:
4866 		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
4867 		break;
4868 	case SCTP_NODELAY:
4869 		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
4870 		break;
4871 	case SCTP_RTOINFO:
4872 		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
4873 		break;
4874 	case SCTP_ASSOCINFO:
4875 		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
4876 		break;
4877 	case SCTP_I_WANT_MAPPED_V4_ADDR:
4878 		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
4879 		break;
4880 	case SCTP_MAXSEG:
4881 		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
4882 		break;
4883 	case SCTP_GET_PEER_ADDR_INFO:
4884 		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
4885 							optlen);
4886 		break;
4887 	case SCTP_ADAPTATION_LAYER:
4888 		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
4889 							optlen);
4890 		break;
4891 	case SCTP_CONTEXT:
4892 		retval = sctp_getsockopt_context(sk, len, optval, optlen);
4893 		break;
4894 	case SCTP_FRAGMENT_INTERLEAVE:
4895 		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
4896 							     optlen);
4897 		break;
4898 	case SCTP_PARTIAL_DELIVERY_POINT:
4899 		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
4900 								optlen);
4901 		break;
4902 	case SCTP_MAX_BURST:
4903 		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
4904 		break;
4905 	default:
4906 		retval = -ENOPROTOOPT;
4907 		break;
4908 	}
4909 
4910 	sctp_release_sock(sk);
4911 	return retval;
4912 }
4913 
4914 static void sctp_hash(struct sock *sk)
4915 {
4916 	/* STUB */
4917 }
4918 
4919 static void sctp_unhash(struct sock *sk)
4920 {
4921 	/* STUB */
4922 }
4923 
4924 /* Check if port is acceptable.  Possibly find first available port.
4925  *
4926  * The port hash table (contained in the 'global' SCTP protocol storage
4927  * returned by struct sctp_protocol *sctp_get_protocol()). The hash
4928  * table is an array of 4096 lists (sctp_bind_hashbucket). Each
4929  * list (the list number is the port number hashed out, so as you
4930  * would expect from a hash function, all the ports in a given list have
4931  * such a number that hashes out to the same list number; you were
4932  * expecting that, right?); so each list has a set of ports, with a
4933  * link to the socket (struct sock) that uses it, the port number and
4934  * a fastreuse flag (FIXME: NPI ipg).
4935  */
4936 static struct sctp_bind_bucket *sctp_bucket_create(
4937 	struct sctp_bind_hashbucket *head, unsigned short snum);
4938 
4939 static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
4940 {
4941 	struct sctp_bind_hashbucket *head; /* hash list */
4942 	struct sctp_bind_bucket *pp; /* hash list port iterator */
4943 	unsigned short snum;
4944 	int ret;
4945 
4946 	snum = ntohs(addr->v4.sin_port);
4947 
4948 	SCTP_DEBUG_PRINTK("sctp_get_port() begins, snum=%d\n", snum);
4949 	sctp_local_bh_disable();
4950 
4951 	if (snum == 0) {
4952 		/* Search for an available port.
4953 		 *
4954 		 * 'sctp_port_rover' was the last port assigned, so
4955 		 * we start to search from 'sctp_port_rover +
4956 		 * 1'. What we do is first check if port 'rover' is
4957 		 * already in the hash table; if not, we use that; if
4958 		 * it is, we try next.
4959 		 */
4960 		int low = sysctl_local_port_range[0];
4961 		int high = sysctl_local_port_range[1];
4962 		int remaining = (high - low) + 1;
4963 		int rover;
4964 		int index;
4965 
4966 		sctp_spin_lock(&sctp_port_alloc_lock);
4967 		rover = sctp_port_rover;
4968 		do {
4969 			rover++;
4970 			if ((rover < low) || (rover > high))
4971 				rover = low;
4972 			index = sctp_phashfn(rover);
4973 			head = &sctp_port_hashtable[index];
4974 			sctp_spin_lock(&head->lock);
4975 			for (pp = head->chain; pp; pp = pp->next)
4976 				if (pp->port == rover)
4977 					goto next;
4978 			break;
4979 		next:
4980 			sctp_spin_unlock(&head->lock);
4981 		} while (--remaining > 0);
4982 		sctp_port_rover = rover;
4983 		sctp_spin_unlock(&sctp_port_alloc_lock);
4984 
4985 		/* Exhausted local port range during search? */
4986 		ret = 1;
4987 		if (remaining <= 0)
4988 			goto fail;
4989 
4990 		/* OK, here is the one we will use.  HEAD (the port
4991 		 * hash table list entry) is non-NULL and we hold it's
4992 		 * mutex.
4993 		 */
4994 		snum = rover;
4995 	} else {
4996 		/* We are given an specific port number; we verify
4997 		 * that it is not being used. If it is used, we will
4998 		 * exahust the search in the hash list corresponding
4999 		 * to the port number (snum) - we detect that with the
5000 		 * port iterator, pp being NULL.
5001 		 */
5002 		head = &sctp_port_hashtable[sctp_phashfn(snum)];
5003 		sctp_spin_lock(&head->lock);
5004 		for (pp = head->chain; pp; pp = pp->next) {
5005 			if (pp->port == snum)
5006 				goto pp_found;
5007 		}
5008 	}
5009 	pp = NULL;
5010 	goto pp_not_found;
5011 pp_found:
5012 	if (!hlist_empty(&pp->owner)) {
5013 		/* We had a port hash table hit - there is an
5014 		 * available port (pp != NULL) and it is being
5015 		 * used by other socket (pp->owner not empty); that other
5016 		 * socket is going to be sk2.
5017 		 */
5018 		int reuse = sk->sk_reuse;
5019 		struct sock *sk2;
5020 		struct hlist_node *node;
5021 
5022 		SCTP_DEBUG_PRINTK("sctp_get_port() found a possible match\n");
5023 		if (pp->fastreuse && sk->sk_reuse &&
5024 			sk->sk_state != SCTP_SS_LISTENING)
5025 			goto success;
5026 
5027 		/* Run through the list of sockets bound to the port
5028 		 * (pp->port) [via the pointers bind_next and
5029 		 * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
5030 		 * we get the endpoint they describe and run through
5031 		 * the endpoint's list of IP (v4 or v6) addresses,
5032 		 * comparing each of the addresses with the address of
5033 		 * the socket sk. If we find a match, then that means
5034 		 * that this port/socket (sk) combination are already
5035 		 * in an endpoint.
5036 		 */
5037 		sk_for_each_bound(sk2, node, &pp->owner) {
5038 			struct sctp_endpoint *ep2;
5039 			ep2 = sctp_sk(sk2)->ep;
5040 
5041 			if (reuse && sk2->sk_reuse &&
5042 			    sk2->sk_state != SCTP_SS_LISTENING)
5043 				continue;
5044 
5045 			if (sctp_bind_addr_match(&ep2->base.bind_addr, addr,
5046 						 sctp_sk(sk))) {
5047 				ret = (long)sk2;
5048 				goto fail_unlock;
5049 			}
5050 		}
5051 		SCTP_DEBUG_PRINTK("sctp_get_port(): Found a match\n");
5052 	}
5053 pp_not_found:
5054 	/* If there was a hash table miss, create a new port.  */
5055 	ret = 1;
5056 	if (!pp && !(pp = sctp_bucket_create(head, snum)))
5057 		goto fail_unlock;
5058 
5059 	/* In either case (hit or miss), make sure fastreuse is 1 only
5060 	 * if sk->sk_reuse is too (that is, if the caller requested
5061 	 * SO_REUSEADDR on this socket -sk-).
5062 	 */
5063 	if (hlist_empty(&pp->owner)) {
5064 		if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
5065 			pp->fastreuse = 1;
5066 		else
5067 			pp->fastreuse = 0;
5068 	} else if (pp->fastreuse &&
5069 		(!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
5070 		pp->fastreuse = 0;
5071 
5072 	/* We are set, so fill up all the data in the hash table
5073 	 * entry, tie the socket list information with the rest of the
5074 	 * sockets FIXME: Blurry, NPI (ipg).
5075 	 */
5076 success:
5077 	if (!sctp_sk(sk)->bind_hash) {
5078 		inet_sk(sk)->num = snum;
5079 		sk_add_bind_node(sk, &pp->owner);
5080 		sctp_sk(sk)->bind_hash = pp;
5081 	}
5082 	ret = 0;
5083 
5084 fail_unlock:
5085 	sctp_spin_unlock(&head->lock);
5086 
5087 fail:
5088 	sctp_local_bh_enable();
5089 	return ret;
5090 }
5091 
5092 /* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
5093  * port is requested.
5094  */
5095 static int sctp_get_port(struct sock *sk, unsigned short snum)
5096 {
5097 	long ret;
5098 	union sctp_addr addr;
5099 	struct sctp_af *af = sctp_sk(sk)->pf->af;
5100 
5101 	/* Set up a dummy address struct from the sk. */
5102 	af->from_sk(&addr, sk);
5103 	addr.v4.sin_port = htons(snum);
5104 
5105 	/* Note: sk->sk_num gets filled in if ephemeral port request. */
5106 	ret = sctp_get_port_local(sk, &addr);
5107 
5108 	return (ret ? 1 : 0);
5109 }
5110 
5111 /*
5112  * 3.1.3 listen() - UDP Style Syntax
5113  *
5114  *   By default, new associations are not accepted for UDP style sockets.
5115  *   An application uses listen() to mark a socket as being able to
5116  *   accept new associations.
5117  */
5118 SCTP_STATIC int sctp_seqpacket_listen(struct sock *sk, int backlog)
5119 {
5120 	struct sctp_sock *sp = sctp_sk(sk);
5121 	struct sctp_endpoint *ep = sp->ep;
5122 
5123 	/* Only UDP style sockets that are not peeled off are allowed to
5124 	 * listen().
5125 	 */
5126 	if (!sctp_style(sk, UDP))
5127 		return -EINVAL;
5128 
5129 	/* If backlog is zero, disable listening. */
5130 	if (!backlog) {
5131 		if (sctp_sstate(sk, CLOSED))
5132 			return 0;
5133 
5134 		sctp_unhash_endpoint(ep);
5135 		sk->sk_state = SCTP_SS_CLOSED;
5136 	}
5137 
5138 	/* Return if we are already listening. */
5139 	if (sctp_sstate(sk, LISTENING))
5140 		return 0;
5141 
5142 	/*
5143 	 * If a bind() or sctp_bindx() is not called prior to a listen()
5144 	 * call that allows new associations to be accepted, the system
5145 	 * picks an ephemeral port and will choose an address set equivalent
5146 	 * to binding with a wildcard address.
5147 	 *
5148 	 * This is not currently spelled out in the SCTP sockets
5149 	 * extensions draft, but follows the practice as seen in TCP
5150 	 * sockets.
5151 	 *
5152 	 * Additionally, turn off fastreuse flag since we are not listening
5153 	 */
5154 	sk->sk_state = SCTP_SS_LISTENING;
5155 	if (!ep->base.bind_addr.port) {
5156 		if (sctp_autobind(sk))
5157 			return -EAGAIN;
5158 	} else
5159 		sctp_sk(sk)->bind_hash->fastreuse = 0;
5160 
5161 	sctp_hash_endpoint(ep);
5162 	return 0;
5163 }
5164 
5165 /*
5166  * 4.1.3 listen() - TCP Style Syntax
5167  *
5168  *   Applications uses listen() to ready the SCTP endpoint for accepting
5169  *   inbound associations.
5170  */
5171 SCTP_STATIC int sctp_stream_listen(struct sock *sk, int backlog)
5172 {
5173 	struct sctp_sock *sp = sctp_sk(sk);
5174 	struct sctp_endpoint *ep = sp->ep;
5175 
5176 	/* If backlog is zero, disable listening. */
5177 	if (!backlog) {
5178 		if (sctp_sstate(sk, CLOSED))
5179 			return 0;
5180 
5181 		sctp_unhash_endpoint(ep);
5182 		sk->sk_state = SCTP_SS_CLOSED;
5183 	}
5184 
5185 	if (sctp_sstate(sk, LISTENING))
5186 		return 0;
5187 
5188 	/*
5189 	 * If a bind() or sctp_bindx() is not called prior to a listen()
5190 	 * call that allows new associations to be accepted, the system
5191 	 * picks an ephemeral port and will choose an address set equivalent
5192 	 * to binding with a wildcard address.
5193 	 *
5194 	 * This is not currently spelled out in the SCTP sockets
5195 	 * extensions draft, but follows the practice as seen in TCP
5196 	 * sockets.
5197 	 */
5198 	sk->sk_state = SCTP_SS_LISTENING;
5199 	if (!ep->base.bind_addr.port) {
5200 		if (sctp_autobind(sk))
5201 			return -EAGAIN;
5202 	} else
5203 		sctp_sk(sk)->bind_hash->fastreuse = 0;
5204 
5205 	sk->sk_max_ack_backlog = backlog;
5206 	sctp_hash_endpoint(ep);
5207 	return 0;
5208 }
5209 
5210 /*
5211  *  Move a socket to LISTENING state.
5212  */
5213 int sctp_inet_listen(struct socket *sock, int backlog)
5214 {
5215 	struct sock *sk = sock->sk;
5216 	struct crypto_hash *tfm = NULL;
5217 	int err = -EINVAL;
5218 
5219 	if (unlikely(backlog < 0))
5220 		goto out;
5221 
5222 	sctp_lock_sock(sk);
5223 
5224 	if (sock->state != SS_UNCONNECTED)
5225 		goto out;
5226 
5227 	/* Allocate HMAC for generating cookie. */
5228 	if (sctp_hmac_alg) {
5229 		tfm = crypto_alloc_hash(sctp_hmac_alg, 0, CRYPTO_ALG_ASYNC);
5230 		if (!tfm) {
5231 			err = -ENOSYS;
5232 			goto out;
5233 		}
5234 	}
5235 
5236 	switch (sock->type) {
5237 	case SOCK_SEQPACKET:
5238 		err = sctp_seqpacket_listen(sk, backlog);
5239 		break;
5240 	case SOCK_STREAM:
5241 		err = sctp_stream_listen(sk, backlog);
5242 		break;
5243 	default:
5244 		break;
5245 	}
5246 
5247 	if (err)
5248 		goto cleanup;
5249 
5250 	/* Store away the transform reference. */
5251 	sctp_sk(sk)->hmac = tfm;
5252 out:
5253 	sctp_release_sock(sk);
5254 	return err;
5255 cleanup:
5256 	crypto_free_hash(tfm);
5257 	goto out;
5258 }
5259 
5260 /*
5261  * This function is done by modeling the current datagram_poll() and the
5262  * tcp_poll().  Note that, based on these implementations, we don't
5263  * lock the socket in this function, even though it seems that,
5264  * ideally, locking or some other mechanisms can be used to ensure
5265  * the integrity of the counters (sndbuf and wmem_alloc) used
5266  * in this place.  We assume that we don't need locks either until proven
5267  * otherwise.
5268  *
5269  * Another thing to note is that we include the Async I/O support
5270  * here, again, by modeling the current TCP/UDP code.  We don't have
5271  * a good way to test with it yet.
5272  */
5273 unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
5274 {
5275 	struct sock *sk = sock->sk;
5276 	struct sctp_sock *sp = sctp_sk(sk);
5277 	unsigned int mask;
5278 
5279 	poll_wait(file, sk->sk_sleep, wait);
5280 
5281 	/* A TCP-style listening socket becomes readable when the accept queue
5282 	 * is not empty.
5283 	 */
5284 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
5285 		return (!list_empty(&sp->ep->asocs)) ?
5286 			(POLLIN | POLLRDNORM) : 0;
5287 
5288 	mask = 0;
5289 
5290 	/* Is there any exceptional events?  */
5291 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
5292 		mask |= POLLERR;
5293 	if (sk->sk_shutdown & RCV_SHUTDOWN)
5294 		mask |= POLLRDHUP;
5295 	if (sk->sk_shutdown == SHUTDOWN_MASK)
5296 		mask |= POLLHUP;
5297 
5298 	/* Is it readable?  Reconsider this code with TCP-style support.  */
5299 	if (!skb_queue_empty(&sk->sk_receive_queue) ||
5300 	    (sk->sk_shutdown & RCV_SHUTDOWN))
5301 		mask |= POLLIN | POLLRDNORM;
5302 
5303 	/* The association is either gone or not ready.  */
5304 	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
5305 		return mask;
5306 
5307 	/* Is it writable?  */
5308 	if (sctp_writeable(sk)) {
5309 		mask |= POLLOUT | POLLWRNORM;
5310 	} else {
5311 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
5312 		/*
5313 		 * Since the socket is not locked, the buffer
5314 		 * might be made available after the writeable check and
5315 		 * before the bit is set.  This could cause a lost I/O
5316 		 * signal.  tcp_poll() has a race breaker for this race
5317 		 * condition.  Based on their implementation, we put
5318 		 * in the following code to cover it as well.
5319 		 */
5320 		if (sctp_writeable(sk))
5321 			mask |= POLLOUT | POLLWRNORM;
5322 	}
5323 	return mask;
5324 }
5325 
5326 /********************************************************************
5327  * 2nd Level Abstractions
5328  ********************************************************************/
5329 
5330 static struct sctp_bind_bucket *sctp_bucket_create(
5331 	struct sctp_bind_hashbucket *head, unsigned short snum)
5332 {
5333 	struct sctp_bind_bucket *pp;
5334 
5335 	pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
5336 	SCTP_DBG_OBJCNT_INC(bind_bucket);
5337 	if (pp) {
5338 		pp->port = snum;
5339 		pp->fastreuse = 0;
5340 		INIT_HLIST_HEAD(&pp->owner);
5341 		if ((pp->next = head->chain) != NULL)
5342 			pp->next->pprev = &pp->next;
5343 		head->chain = pp;
5344 		pp->pprev = &head->chain;
5345 	}
5346 	return pp;
5347 }
5348 
5349 /* Caller must hold hashbucket lock for this tb with local BH disabled */
5350 static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
5351 {
5352 	if (pp && hlist_empty(&pp->owner)) {
5353 		if (pp->next)
5354 			pp->next->pprev = pp->pprev;
5355 		*(pp->pprev) = pp->next;
5356 		kmem_cache_free(sctp_bucket_cachep, pp);
5357 		SCTP_DBG_OBJCNT_DEC(bind_bucket);
5358 	}
5359 }
5360 
5361 /* Release this socket's reference to a local port.  */
5362 static inline void __sctp_put_port(struct sock *sk)
5363 {
5364 	struct sctp_bind_hashbucket *head =
5365 		&sctp_port_hashtable[sctp_phashfn(inet_sk(sk)->num)];
5366 	struct sctp_bind_bucket *pp;
5367 
5368 	sctp_spin_lock(&head->lock);
5369 	pp = sctp_sk(sk)->bind_hash;
5370 	__sk_del_bind_node(sk);
5371 	sctp_sk(sk)->bind_hash = NULL;
5372 	inet_sk(sk)->num = 0;
5373 	sctp_bucket_destroy(pp);
5374 	sctp_spin_unlock(&head->lock);
5375 }
5376 
5377 void sctp_put_port(struct sock *sk)
5378 {
5379 	sctp_local_bh_disable();
5380 	__sctp_put_port(sk);
5381 	sctp_local_bh_enable();
5382 }
5383 
5384 /*
5385  * The system picks an ephemeral port and choose an address set equivalent
5386  * to binding with a wildcard address.
5387  * One of those addresses will be the primary address for the association.
5388  * This automatically enables the multihoming capability of SCTP.
5389  */
5390 static int sctp_autobind(struct sock *sk)
5391 {
5392 	union sctp_addr autoaddr;
5393 	struct sctp_af *af;
5394 	__be16 port;
5395 
5396 	/* Initialize a local sockaddr structure to INADDR_ANY. */
5397 	af = sctp_sk(sk)->pf->af;
5398 
5399 	port = htons(inet_sk(sk)->num);
5400 	af->inaddr_any(&autoaddr, port);
5401 
5402 	return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
5403 }
5404 
5405 /* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
5406  *
5407  * From RFC 2292
5408  * 4.2 The cmsghdr Structure *
5409  *
5410  * When ancillary data is sent or received, any number of ancillary data
5411  * objects can be specified by the msg_control and msg_controllen members of
5412  * the msghdr structure, because each object is preceded by
5413  * a cmsghdr structure defining the object's length (the cmsg_len member).
5414  * Historically Berkeley-derived implementations have passed only one object
5415  * at a time, but this API allows multiple objects to be
5416  * passed in a single call to sendmsg() or recvmsg(). The following example
5417  * shows two ancillary data objects in a control buffer.
5418  *
5419  *   |<--------------------------- msg_controllen -------------------------->|
5420  *   |                                                                       |
5421  *
5422  *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
5423  *
5424  *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
5425  *   |                                   |                                   |
5426  *
5427  *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
5428  *
5429  *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
5430  *   |                                |  |                                |  |
5431  *
5432  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5433  *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
5434  *
5435  *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
5436  *
5437  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5438  *    ^
5439  *    |
5440  *
5441  * msg_control
5442  * points here
5443  */
5444 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *msg,
5445 				  sctp_cmsgs_t *cmsgs)
5446 {
5447 	struct cmsghdr *cmsg;
5448 
5449 	for (cmsg = CMSG_FIRSTHDR(msg);
5450 	     cmsg != NULL;
5451 	     cmsg = CMSG_NXTHDR((struct msghdr*)msg, cmsg)) {
5452 		if (!CMSG_OK(msg, cmsg))
5453 			return -EINVAL;
5454 
5455 		/* Should we parse this header or ignore?  */
5456 		if (cmsg->cmsg_level != IPPROTO_SCTP)
5457 			continue;
5458 
5459 		/* Strictly check lengths following example in SCM code.  */
5460 		switch (cmsg->cmsg_type) {
5461 		case SCTP_INIT:
5462 			/* SCTP Socket API Extension
5463 			 * 5.2.1 SCTP Initiation Structure (SCTP_INIT)
5464 			 *
5465 			 * This cmsghdr structure provides information for
5466 			 * initializing new SCTP associations with sendmsg().
5467 			 * The SCTP_INITMSG socket option uses this same data
5468 			 * structure.  This structure is not used for
5469 			 * recvmsg().
5470 			 *
5471 			 * cmsg_level    cmsg_type      cmsg_data[]
5472 			 * ------------  ------------   ----------------------
5473 			 * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
5474 			 */
5475 			if (cmsg->cmsg_len !=
5476 			    CMSG_LEN(sizeof(struct sctp_initmsg)))
5477 				return -EINVAL;
5478 			cmsgs->init = (struct sctp_initmsg *)CMSG_DATA(cmsg);
5479 			break;
5480 
5481 		case SCTP_SNDRCV:
5482 			/* SCTP Socket API Extension
5483 			 * 5.2.2 SCTP Header Information Structure(SCTP_SNDRCV)
5484 			 *
5485 			 * This cmsghdr structure specifies SCTP options for
5486 			 * sendmsg() and describes SCTP header information
5487 			 * about a received message through recvmsg().
5488 			 *
5489 			 * cmsg_level    cmsg_type      cmsg_data[]
5490 			 * ------------  ------------   ----------------------
5491 			 * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
5492 			 */
5493 			if (cmsg->cmsg_len !=
5494 			    CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
5495 				return -EINVAL;
5496 
5497 			cmsgs->info =
5498 				(struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
5499 
5500 			/* Minimally, validate the sinfo_flags. */
5501 			if (cmsgs->info->sinfo_flags &
5502 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
5503 			      SCTP_ABORT | SCTP_EOF))
5504 				return -EINVAL;
5505 			break;
5506 
5507 		default:
5508 			return -EINVAL;
5509 		}
5510 	}
5511 	return 0;
5512 }
5513 
5514 /*
5515  * Wait for a packet..
5516  * Note: This function is the same function as in core/datagram.c
5517  * with a few modifications to make lksctp work.
5518  */
5519 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p)
5520 {
5521 	int error;
5522 	DEFINE_WAIT(wait);
5523 
5524 	prepare_to_wait_exclusive(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
5525 
5526 	/* Socket errors? */
5527 	error = sock_error(sk);
5528 	if (error)
5529 		goto out;
5530 
5531 	if (!skb_queue_empty(&sk->sk_receive_queue))
5532 		goto ready;
5533 
5534 	/* Socket shut down?  */
5535 	if (sk->sk_shutdown & RCV_SHUTDOWN)
5536 		goto out;
5537 
5538 	/* Sequenced packets can come disconnected.  If so we report the
5539 	 * problem.
5540 	 */
5541 	error = -ENOTCONN;
5542 
5543 	/* Is there a good reason to think that we may receive some data?  */
5544 	if (list_empty(&sctp_sk(sk)->ep->asocs) && !sctp_sstate(sk, LISTENING))
5545 		goto out;
5546 
5547 	/* Handle signals.  */
5548 	if (signal_pending(current))
5549 		goto interrupted;
5550 
5551 	/* Let another process have a go.  Since we are going to sleep
5552 	 * anyway.  Note: This may cause odd behaviors if the message
5553 	 * does not fit in the user's buffer, but this seems to be the
5554 	 * only way to honor MSG_DONTWAIT realistically.
5555 	 */
5556 	sctp_release_sock(sk);
5557 	*timeo_p = schedule_timeout(*timeo_p);
5558 	sctp_lock_sock(sk);
5559 
5560 ready:
5561 	finish_wait(sk->sk_sleep, &wait);
5562 	return 0;
5563 
5564 interrupted:
5565 	error = sock_intr_errno(*timeo_p);
5566 
5567 out:
5568 	finish_wait(sk->sk_sleep, &wait);
5569 	*err = error;
5570 	return error;
5571 }
5572 
5573 /* Receive a datagram.
5574  * Note: This is pretty much the same routine as in core/datagram.c
5575  * with a few changes to make lksctp work.
5576  */
5577 static struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
5578 					      int noblock, int *err)
5579 {
5580 	int error;
5581 	struct sk_buff *skb;
5582 	long timeo;
5583 
5584 	timeo = sock_rcvtimeo(sk, noblock);
5585 
5586 	SCTP_DEBUG_PRINTK("Timeout: timeo: %ld, MAX: %ld.\n",
5587 			  timeo, MAX_SCHEDULE_TIMEOUT);
5588 
5589 	do {
5590 		/* Again only user level code calls this function,
5591 		 * so nothing interrupt level
5592 		 * will suddenly eat the receive_queue.
5593 		 *
5594 		 *  Look at current nfs client by the way...
5595 		 *  However, this function was corrent in any case. 8)
5596 		 */
5597 		if (flags & MSG_PEEK) {
5598 			spin_lock_bh(&sk->sk_receive_queue.lock);
5599 			skb = skb_peek(&sk->sk_receive_queue);
5600 			if (skb)
5601 				atomic_inc(&skb->users);
5602 			spin_unlock_bh(&sk->sk_receive_queue.lock);
5603 		} else {
5604 			skb = skb_dequeue(&sk->sk_receive_queue);
5605 		}
5606 
5607 		if (skb)
5608 			return skb;
5609 
5610 		/* Caller is allowed not to check sk->sk_err before calling. */
5611 		error = sock_error(sk);
5612 		if (error)
5613 			goto no_packet;
5614 
5615 		if (sk->sk_shutdown & RCV_SHUTDOWN)
5616 			break;
5617 
5618 		/* User doesn't want to wait.  */
5619 		error = -EAGAIN;
5620 		if (!timeo)
5621 			goto no_packet;
5622 	} while (sctp_wait_for_packet(sk, err, &timeo) == 0);
5623 
5624 	return NULL;
5625 
5626 no_packet:
5627 	*err = error;
5628 	return NULL;
5629 }
5630 
5631 /* If sndbuf has changed, wake up per association sndbuf waiters.  */
5632 static void __sctp_write_space(struct sctp_association *asoc)
5633 {
5634 	struct sock *sk = asoc->base.sk;
5635 	struct socket *sock = sk->sk_socket;
5636 
5637 	if ((sctp_wspace(asoc) > 0) && sock) {
5638 		if (waitqueue_active(&asoc->wait))
5639 			wake_up_interruptible(&asoc->wait);
5640 
5641 		if (sctp_writeable(sk)) {
5642 			if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
5643 				wake_up_interruptible(sk->sk_sleep);
5644 
5645 			/* Note that we try to include the Async I/O support
5646 			 * here by modeling from the current TCP/UDP code.
5647 			 * We have not tested with it yet.
5648 			 */
5649 			if (sock->fasync_list &&
5650 			    !(sk->sk_shutdown & SEND_SHUTDOWN))
5651 				sock_wake_async(sock, 2, POLL_OUT);
5652 		}
5653 	}
5654 }
5655 
5656 /* Do accounting for the sndbuf space.
5657  * Decrement the used sndbuf space of the corresponding association by the
5658  * data size which was just transmitted(freed).
5659  */
5660 static void sctp_wfree(struct sk_buff *skb)
5661 {
5662 	struct sctp_association *asoc;
5663 	struct sctp_chunk *chunk;
5664 	struct sock *sk;
5665 
5666 	/* Get the saved chunk pointer.  */
5667 	chunk = *((struct sctp_chunk **)(skb->cb));
5668 	asoc = chunk->asoc;
5669 	sk = asoc->base.sk;
5670 	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
5671 				sizeof(struct sk_buff) +
5672 				sizeof(struct sctp_chunk);
5673 
5674 	atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
5675 
5676 	sock_wfree(skb);
5677 	__sctp_write_space(asoc);
5678 
5679 	sctp_association_put(asoc);
5680 }
5681 
5682 /* Do accounting for the receive space on the socket.
5683  * Accounting for the association is done in ulpevent.c
5684  * We set this as a destructor for the cloned data skbs so that
5685  * accounting is done at the correct time.
5686  */
5687 void sctp_sock_rfree(struct sk_buff *skb)
5688 {
5689 	struct sock *sk = skb->sk;
5690 	struct sctp_ulpevent *event = sctp_skb2event(skb);
5691 
5692 	atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
5693 }
5694 
5695 
5696 /* Helper function to wait for space in the sndbuf.  */
5697 static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
5698 				size_t msg_len)
5699 {
5700 	struct sock *sk = asoc->base.sk;
5701 	int err = 0;
5702 	long current_timeo = *timeo_p;
5703 	DEFINE_WAIT(wait);
5704 
5705 	SCTP_DEBUG_PRINTK("wait_for_sndbuf: asoc=%p, timeo=%ld, msg_len=%zu\n",
5706 			  asoc, (long)(*timeo_p), msg_len);
5707 
5708 	/* Increment the association's refcnt.  */
5709 	sctp_association_hold(asoc);
5710 
5711 	/* Wait on the association specific sndbuf space. */
5712 	for (;;) {
5713 		prepare_to_wait_exclusive(&asoc->wait, &wait,
5714 					  TASK_INTERRUPTIBLE);
5715 		if (!*timeo_p)
5716 			goto do_nonblock;
5717 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
5718 		    asoc->base.dead)
5719 			goto do_error;
5720 		if (signal_pending(current))
5721 			goto do_interrupted;
5722 		if (msg_len <= sctp_wspace(asoc))
5723 			break;
5724 
5725 		/* Let another process have a go.  Since we are going
5726 		 * to sleep anyway.
5727 		 */
5728 		sctp_release_sock(sk);
5729 		current_timeo = schedule_timeout(current_timeo);
5730 		BUG_ON(sk != asoc->base.sk);
5731 		sctp_lock_sock(sk);
5732 
5733 		*timeo_p = current_timeo;
5734 	}
5735 
5736 out:
5737 	finish_wait(&asoc->wait, &wait);
5738 
5739 	/* Release the association's refcnt.  */
5740 	sctp_association_put(asoc);
5741 
5742 	return err;
5743 
5744 do_error:
5745 	err = -EPIPE;
5746 	goto out;
5747 
5748 do_interrupted:
5749 	err = sock_intr_errno(*timeo_p);
5750 	goto out;
5751 
5752 do_nonblock:
5753 	err = -EAGAIN;
5754 	goto out;
5755 }
5756 
5757 /* If socket sndbuf has changed, wake up all per association waiters.  */
5758 void sctp_write_space(struct sock *sk)
5759 {
5760 	struct sctp_association *asoc;
5761 	struct list_head *pos;
5762 
5763 	/* Wake up the tasks in each wait queue.  */
5764 	list_for_each(pos, &((sctp_sk(sk))->ep->asocs)) {
5765 		asoc = list_entry(pos, struct sctp_association, asocs);
5766 		__sctp_write_space(asoc);
5767 	}
5768 }
5769 
5770 /* Is there any sndbuf space available on the socket?
5771  *
5772  * Note that sk_wmem_alloc is the sum of the send buffers on all of the
5773  * associations on the same socket.  For a UDP-style socket with
5774  * multiple associations, it is possible for it to be "unwriteable"
5775  * prematurely.  I assume that this is acceptable because
5776  * a premature "unwriteable" is better than an accidental "writeable" which
5777  * would cause an unwanted block under certain circumstances.  For the 1-1
5778  * UDP-style sockets or TCP-style sockets, this code should work.
5779  *  - Daisy
5780  */
5781 static int sctp_writeable(struct sock *sk)
5782 {
5783 	int amt = 0;
5784 
5785 	amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
5786 	if (amt < 0)
5787 		amt = 0;
5788 	return amt;
5789 }
5790 
5791 /* Wait for an association to go into ESTABLISHED state. If timeout is 0,
5792  * returns immediately with EINPROGRESS.
5793  */
5794 static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
5795 {
5796 	struct sock *sk = asoc->base.sk;
5797 	int err = 0;
5798 	long current_timeo = *timeo_p;
5799 	DEFINE_WAIT(wait);
5800 
5801 	SCTP_DEBUG_PRINTK("%s: asoc=%p, timeo=%ld\n", __FUNCTION__, asoc,
5802 			  (long)(*timeo_p));
5803 
5804 	/* Increment the association's refcnt.  */
5805 	sctp_association_hold(asoc);
5806 
5807 	for (;;) {
5808 		prepare_to_wait_exclusive(&asoc->wait, &wait,
5809 					  TASK_INTERRUPTIBLE);
5810 		if (!*timeo_p)
5811 			goto do_nonblock;
5812 		if (sk->sk_shutdown & RCV_SHUTDOWN)
5813 			break;
5814 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
5815 		    asoc->base.dead)
5816 			goto do_error;
5817 		if (signal_pending(current))
5818 			goto do_interrupted;
5819 
5820 		if (sctp_state(asoc, ESTABLISHED))
5821 			break;
5822 
5823 		/* Let another process have a go.  Since we are going
5824 		 * to sleep anyway.
5825 		 */
5826 		sctp_release_sock(sk);
5827 		current_timeo = schedule_timeout(current_timeo);
5828 		sctp_lock_sock(sk);
5829 
5830 		*timeo_p = current_timeo;
5831 	}
5832 
5833 out:
5834 	finish_wait(&asoc->wait, &wait);
5835 
5836 	/* Release the association's refcnt.  */
5837 	sctp_association_put(asoc);
5838 
5839 	return err;
5840 
5841 do_error:
5842 	if (asoc->init_err_counter + 1 > asoc->max_init_attempts)
5843 		err = -ETIMEDOUT;
5844 	else
5845 		err = -ECONNREFUSED;
5846 	goto out;
5847 
5848 do_interrupted:
5849 	err = sock_intr_errno(*timeo_p);
5850 	goto out;
5851 
5852 do_nonblock:
5853 	err = -EINPROGRESS;
5854 	goto out;
5855 }
5856 
5857 static int sctp_wait_for_accept(struct sock *sk, long timeo)
5858 {
5859 	struct sctp_endpoint *ep;
5860 	int err = 0;
5861 	DEFINE_WAIT(wait);
5862 
5863 	ep = sctp_sk(sk)->ep;
5864 
5865 
5866 	for (;;) {
5867 		prepare_to_wait_exclusive(sk->sk_sleep, &wait,
5868 					  TASK_INTERRUPTIBLE);
5869 
5870 		if (list_empty(&ep->asocs)) {
5871 			sctp_release_sock(sk);
5872 			timeo = schedule_timeout(timeo);
5873 			sctp_lock_sock(sk);
5874 		}
5875 
5876 		err = -EINVAL;
5877 		if (!sctp_sstate(sk, LISTENING))
5878 			break;
5879 
5880 		err = 0;
5881 		if (!list_empty(&ep->asocs))
5882 			break;
5883 
5884 		err = sock_intr_errno(timeo);
5885 		if (signal_pending(current))
5886 			break;
5887 
5888 		err = -EAGAIN;
5889 		if (!timeo)
5890 			break;
5891 	}
5892 
5893 	finish_wait(sk->sk_sleep, &wait);
5894 
5895 	return err;
5896 }
5897 
5898 void sctp_wait_for_close(struct sock *sk, long timeout)
5899 {
5900 	DEFINE_WAIT(wait);
5901 
5902 	do {
5903 		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
5904 		if (list_empty(&sctp_sk(sk)->ep->asocs))
5905 			break;
5906 		sctp_release_sock(sk);
5907 		timeout = schedule_timeout(timeout);
5908 		sctp_lock_sock(sk);
5909 	} while (!signal_pending(current) && timeout);
5910 
5911 	finish_wait(sk->sk_sleep, &wait);
5912 }
5913 
5914 static void sctp_sock_rfree_frag(struct sk_buff *skb)
5915 {
5916 	struct sk_buff *frag;
5917 
5918 	if (!skb->data_len)
5919 		goto done;
5920 
5921 	/* Don't forget the fragments. */
5922 	for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next)
5923 		sctp_sock_rfree_frag(frag);
5924 
5925 done:
5926 	sctp_sock_rfree(skb);
5927 }
5928 
5929 static void sctp_skb_set_owner_r_frag(struct sk_buff *skb, struct sock *sk)
5930 {
5931 	struct sk_buff *frag;
5932 
5933 	if (!skb->data_len)
5934 		goto done;
5935 
5936 	/* Don't forget the fragments. */
5937 	for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next)
5938 		sctp_skb_set_owner_r_frag(frag, sk);
5939 
5940 done:
5941 	sctp_skb_set_owner_r(skb, sk);
5942 }
5943 
5944 /* Populate the fields of the newsk from the oldsk and migrate the assoc
5945  * and its messages to the newsk.
5946  */
5947 static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
5948 			      struct sctp_association *assoc,
5949 			      sctp_socket_type_t type)
5950 {
5951 	struct sctp_sock *oldsp = sctp_sk(oldsk);
5952 	struct sctp_sock *newsp = sctp_sk(newsk);
5953 	struct sctp_bind_bucket *pp; /* hash list port iterator */
5954 	struct sctp_endpoint *newep = newsp->ep;
5955 	struct sk_buff *skb, *tmp;
5956 	struct sctp_ulpevent *event;
5957 	int flags = 0;
5958 
5959 	/* Migrate socket buffer sizes and all the socket level options to the
5960 	 * new socket.
5961 	 */
5962 	newsk->sk_sndbuf = oldsk->sk_sndbuf;
5963 	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
5964 	/* Brute force copy old sctp opt. */
5965 	inet_sk_copy_descendant(newsk, oldsk);
5966 
5967 	/* Restore the ep value that was overwritten with the above structure
5968 	 * copy.
5969 	 */
5970 	newsp->ep = newep;
5971 	newsp->hmac = NULL;
5972 
5973 	/* Hook this new socket in to the bind_hash list. */
5974 	pp = sctp_sk(oldsk)->bind_hash;
5975 	sk_add_bind_node(newsk, &pp->owner);
5976 	sctp_sk(newsk)->bind_hash = pp;
5977 	inet_sk(newsk)->num = inet_sk(oldsk)->num;
5978 
5979 	/* Copy the bind_addr list from the original endpoint to the new
5980 	 * endpoint so that we can handle restarts properly
5981 	 */
5982 	if (PF_INET6 == assoc->base.sk->sk_family)
5983 		flags = SCTP_ADDR6_ALLOWED;
5984 	if (assoc->peer.ipv4_address)
5985 		flags |= SCTP_ADDR4_PEERSUPP;
5986 	if (assoc->peer.ipv6_address)
5987 		flags |= SCTP_ADDR6_PEERSUPP;
5988 	sctp_bind_addr_copy(&newsp->ep->base.bind_addr,
5989 			     &oldsp->ep->base.bind_addr,
5990 			     SCTP_SCOPE_GLOBAL, GFP_KERNEL, flags);
5991 
5992 	/* Move any messages in the old socket's receive queue that are for the
5993 	 * peeled off association to the new socket's receive queue.
5994 	 */
5995 	sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
5996 		event = sctp_skb2event(skb);
5997 		if (event->asoc == assoc) {
5998 			sctp_sock_rfree_frag(skb);
5999 			__skb_unlink(skb, &oldsk->sk_receive_queue);
6000 			__skb_queue_tail(&newsk->sk_receive_queue, skb);
6001 			sctp_skb_set_owner_r_frag(skb, newsk);
6002 		}
6003 	}
6004 
6005 	/* Clean up any messages pending delivery due to partial
6006 	 * delivery.   Three cases:
6007 	 * 1) No partial deliver;  no work.
6008 	 * 2) Peeling off partial delivery; keep pd_lobby in new pd_lobby.
6009 	 * 3) Peeling off non-partial delivery; move pd_lobby to receive_queue.
6010 	 */
6011 	skb_queue_head_init(&newsp->pd_lobby);
6012 	atomic_set(&sctp_sk(newsk)->pd_mode, assoc->ulpq.pd_mode);
6013 
6014 	if (atomic_read(&sctp_sk(oldsk)->pd_mode)) {
6015 		struct sk_buff_head *queue;
6016 
6017 		/* Decide which queue to move pd_lobby skbs to. */
6018 		if (assoc->ulpq.pd_mode) {
6019 			queue = &newsp->pd_lobby;
6020 		} else
6021 			queue = &newsk->sk_receive_queue;
6022 
6023 		/* Walk through the pd_lobby, looking for skbs that
6024 		 * need moved to the new socket.
6025 		 */
6026 		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
6027 			event = sctp_skb2event(skb);
6028 			if (event->asoc == assoc) {
6029 				sctp_sock_rfree_frag(skb);
6030 				__skb_unlink(skb, &oldsp->pd_lobby);
6031 				__skb_queue_tail(queue, skb);
6032 				sctp_skb_set_owner_r_frag(skb, newsk);
6033 			}
6034 		}
6035 
6036 		/* Clear up any skbs waiting for the partial
6037 		 * delivery to finish.
6038 		 */
6039 		if (assoc->ulpq.pd_mode)
6040 			sctp_clear_pd(oldsk, NULL);
6041 
6042 	}
6043 
6044 	sctp_skb_for_each(skb, &assoc->ulpq.reasm, tmp) {
6045 		sctp_sock_rfree_frag(skb);
6046 		sctp_skb_set_owner_r_frag(skb, newsk);
6047 	}
6048 
6049 	sctp_skb_for_each(skb, &assoc->ulpq.lobby, tmp) {
6050 		sctp_sock_rfree_frag(skb);
6051 		sctp_skb_set_owner_r_frag(skb, newsk);
6052 	}
6053 
6054 	/* Set the type of socket to indicate that it is peeled off from the
6055 	 * original UDP-style socket or created with the accept() call on a
6056 	 * TCP-style socket..
6057 	 */
6058 	newsp->type = type;
6059 
6060 	/* Mark the new socket "in-use" by the user so that any packets
6061 	 * that may arrive on the association after we've moved it are
6062 	 * queued to the backlog.  This prevents a potential race between
6063 	 * backlog processing on the old socket and new-packet processing
6064 	 * on the new socket.
6065 	 */
6066 	sctp_lock_sock(newsk);
6067 	sctp_assoc_migrate(assoc, newsk);
6068 
6069 	/* If the association on the newsk is already closed before accept()
6070 	 * is called, set RCV_SHUTDOWN flag.
6071 	 */
6072 	if (sctp_state(assoc, CLOSED) && sctp_style(newsk, TCP))
6073 		newsk->sk_shutdown |= RCV_SHUTDOWN;
6074 
6075 	newsk->sk_state = SCTP_SS_ESTABLISHED;
6076 	sctp_release_sock(newsk);
6077 }
6078 
6079 /* This proto struct describes the ULP interface for SCTP.  */
6080 struct proto sctp_prot = {
6081 	.name        =	"SCTP",
6082 	.owner       =	THIS_MODULE,
6083 	.close       =	sctp_close,
6084 	.connect     =	sctp_connect,
6085 	.disconnect  =	sctp_disconnect,
6086 	.accept      =	sctp_accept,
6087 	.ioctl       =	sctp_ioctl,
6088 	.init        =	sctp_init_sock,
6089 	.destroy     =	sctp_destroy_sock,
6090 	.shutdown    =	sctp_shutdown,
6091 	.setsockopt  =	sctp_setsockopt,
6092 	.getsockopt  =	sctp_getsockopt,
6093 	.sendmsg     =	sctp_sendmsg,
6094 	.recvmsg     =	sctp_recvmsg,
6095 	.bind        =	sctp_bind,
6096 	.backlog_rcv =	sctp_backlog_rcv,
6097 	.hash        =	sctp_hash,
6098 	.unhash      =	sctp_unhash,
6099 	.get_port    =	sctp_get_port,
6100 	.obj_size    =  sizeof(struct sctp_sock),
6101 };
6102 
6103 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6104 struct proto sctpv6_prot = {
6105 	.name		= "SCTPv6",
6106 	.owner		= THIS_MODULE,
6107 	.close		= sctp_close,
6108 	.connect	= sctp_connect,
6109 	.disconnect	= sctp_disconnect,
6110 	.accept		= sctp_accept,
6111 	.ioctl		= sctp_ioctl,
6112 	.init		= sctp_init_sock,
6113 	.destroy	= sctp_destroy_sock,
6114 	.shutdown	= sctp_shutdown,
6115 	.setsockopt	= sctp_setsockopt,
6116 	.getsockopt	= sctp_getsockopt,
6117 	.sendmsg	= sctp_sendmsg,
6118 	.recvmsg	= sctp_recvmsg,
6119 	.bind		= sctp_bind,
6120 	.backlog_rcv	= sctp_backlog_rcv,
6121 	.hash		= sctp_hash,
6122 	.unhash		= sctp_unhash,
6123 	.get_port	= sctp_get_port,
6124 	.obj_size	= sizeof(struct sctp6_sock),
6125 };
6126 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
6127