xref: /linux/net/sctp/socket.c (revision 492c826b9facefa84995f4dea917e301b5ee0884)
1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2001, 2004
3  * Copyright (c) 1999-2000 Cisco, Inc.
4  * Copyright (c) 1999-2001 Motorola, Inc.
5  * Copyright (c) 2001-2003 Intel Corp.
6  * Copyright (c) 2001-2002 Nokia, Inc.
7  * Copyright (c) 2001 La Monte H.P. Yarroll
8  *
9  * This file is part of the SCTP kernel implementation
10  *
11  * These functions interface with the sockets layer to implement the
12  * SCTP Extensions for the Sockets API.
13  *
14  * Note that the descriptions from the specification are USER level
15  * functions--this file is the functions which populate the struct proto
16  * for SCTP which is the BOTTOM of the sockets interface.
17  *
18  * This SCTP implementation is free software;
19  * you can redistribute it and/or modify it under the terms of
20  * the GNU General Public License as published by
21  * the Free Software Foundation; either version 2, or (at your option)
22  * any later version.
23  *
24  * This SCTP implementation is distributed in the hope that it
25  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
26  *                 ************************
27  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
28  * See the GNU General Public License for more details.
29  *
30  * You should have received a copy of the GNU General Public License
31  * along with GNU CC; see the file COPYING.  If not, 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
61 
62 #include <linux/types.h>
63 #include <linux/kernel.h>
64 #include <linux/wait.h>
65 #include <linux/time.h>
66 #include <linux/ip.h>
67 #include <linux/capability.h>
68 #include <linux/fcntl.h>
69 #include <linux/poll.h>
70 #include <linux/init.h>
71 #include <linux/crypto.h>
72 #include <linux/slab.h>
73 
74 #include <net/ip.h>
75 #include <net/icmp.h>
76 #include <net/route.h>
77 #include <net/ipv6.h>
78 #include <net/inet_common.h>
79 
80 #include <linux/socket.h> /* for sa_family_t */
81 #include <net/sock.h>
82 #include <net/sctp/sctp.h>
83 #include <net/sctp/sm.h>
84 
85 /* WARNING:  Please do not remove the SCTP_STATIC attribute to
86  * any of the functions below as they are used to export functions
87  * used by a project regression testsuite.
88  */
89 
90 /* Forward declarations for internal helper functions. */
91 static int sctp_writeable(struct sock *sk);
92 static void sctp_wfree(struct sk_buff *skb);
93 static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p,
94 				size_t msg_len);
95 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p);
96 static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);
97 static int sctp_wait_for_accept(struct sock *sk, long timeo);
98 static void sctp_wait_for_close(struct sock *sk, long timeo);
99 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
100 					union sctp_addr *addr, int len);
101 static int sctp_bindx_add(struct sock *, struct sockaddr *, int);
102 static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);
103 static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);
104 static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);
105 static int sctp_send_asconf(struct sctp_association *asoc,
106 			    struct sctp_chunk *chunk);
107 static int sctp_do_bind(struct sock *, union sctp_addr *, int);
108 static int sctp_autobind(struct sock *sk);
109 static void sctp_sock_migrate(struct sock *, struct sock *,
110 			      struct sctp_association *, sctp_socket_type_t);
111 static char *sctp_hmac_alg = SCTP_COOKIE_HMAC_ALG;
112 
113 extern struct kmem_cache *sctp_bucket_cachep;
114 extern long sysctl_sctp_mem[3];
115 extern int sysctl_sctp_rmem[3];
116 extern int sysctl_sctp_wmem[3];
117 
118 static int sctp_memory_pressure;
119 static atomic_long_t sctp_memory_allocated;
120 struct percpu_counter sctp_sockets_allocated;
121 
122 static void sctp_enter_memory_pressure(struct sock *sk)
123 {
124 	sctp_memory_pressure = 1;
125 }
126 
127 
128 /* Get the sndbuf space available at the time on the association.  */
129 static inline int sctp_wspace(struct sctp_association *asoc)
130 {
131 	int amt;
132 
133 	if (asoc->ep->sndbuf_policy)
134 		amt = asoc->sndbuf_used;
135 	else
136 		amt = sk_wmem_alloc_get(asoc->base.sk);
137 
138 	if (amt >= asoc->base.sk->sk_sndbuf) {
139 		if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK)
140 			amt = 0;
141 		else {
142 			amt = sk_stream_wspace(asoc->base.sk);
143 			if (amt < 0)
144 				amt = 0;
145 		}
146 	} else {
147 		amt = asoc->base.sk->sk_sndbuf - amt;
148 	}
149 	return amt;
150 }
151 
152 /* Increment the used sndbuf space count of the corresponding association by
153  * the size of the outgoing data chunk.
154  * Also, set the skb destructor for sndbuf accounting later.
155  *
156  * Since it is always 1-1 between chunk and skb, and also a new skb is always
157  * allocated for chunk bundling in sctp_packet_transmit(), we can use the
158  * destructor in the data chunk skb for the purpose of the sndbuf space
159  * tracking.
160  */
161 static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
162 {
163 	struct sctp_association *asoc = chunk->asoc;
164 	struct sock *sk = asoc->base.sk;
165 
166 	/* The sndbuf space is tracked per association.  */
167 	sctp_association_hold(asoc);
168 
169 	skb_set_owner_w(chunk->skb, sk);
170 
171 	chunk->skb->destructor = sctp_wfree;
172 	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
173 	*((struct sctp_chunk **)(chunk->skb->cb)) = chunk;
174 
175 	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
176 				sizeof(struct sk_buff) +
177 				sizeof(struct sctp_chunk);
178 
179 	atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
180 	sk->sk_wmem_queued += chunk->skb->truesize;
181 	sk_mem_charge(sk, chunk->skb->truesize);
182 }
183 
184 /* Verify that this is a valid address. */
185 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
186 				   int len)
187 {
188 	struct sctp_af *af;
189 
190 	/* Verify basic sockaddr. */
191 	af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
192 	if (!af)
193 		return -EINVAL;
194 
195 	/* Is this a valid SCTP address?  */
196 	if (!af->addr_valid(addr, sctp_sk(sk), NULL))
197 		return -EINVAL;
198 
199 	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
200 		return -EINVAL;
201 
202 	return 0;
203 }
204 
205 /* Look up the association by its id.  If this is not a UDP-style
206  * socket, the ID field is always ignored.
207  */
208 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
209 {
210 	struct sctp_association *asoc = NULL;
211 
212 	/* If this is not a UDP-style socket, assoc id should be ignored. */
213 	if (!sctp_style(sk, UDP)) {
214 		/* Return NULL if the socket state is not ESTABLISHED. It
215 		 * could be a TCP-style listening socket or a socket which
216 		 * hasn't yet called connect() to establish an association.
217 		 */
218 		if (!sctp_sstate(sk, ESTABLISHED))
219 			return NULL;
220 
221 		/* Get the first and the only association from the list. */
222 		if (!list_empty(&sctp_sk(sk)->ep->asocs))
223 			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
224 					  struct sctp_association, asocs);
225 		return asoc;
226 	}
227 
228 	/* Otherwise this is a UDP-style socket. */
229 	if (!id || (id == (sctp_assoc_t)-1))
230 		return NULL;
231 
232 	spin_lock_bh(&sctp_assocs_id_lock);
233 	asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
234 	spin_unlock_bh(&sctp_assocs_id_lock);
235 
236 	if (!asoc || (asoc->base.sk != sk) || asoc->base.dead)
237 		return NULL;
238 
239 	return asoc;
240 }
241 
242 /* Look up the transport from an address and an assoc id. If both address and
243  * id are specified, the associations matching the address and the id should be
244  * the same.
245  */
246 static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
247 					      struct sockaddr_storage *addr,
248 					      sctp_assoc_t id)
249 {
250 	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
251 	struct sctp_transport *transport;
252 	union sctp_addr *laddr = (union sctp_addr *)addr;
253 
254 	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
255 					       laddr,
256 					       &transport);
257 
258 	if (!addr_asoc)
259 		return NULL;
260 
261 	id_asoc = sctp_id2assoc(sk, id);
262 	if (id_asoc && (id_asoc != addr_asoc))
263 		return NULL;
264 
265 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
266 						(union sctp_addr *)addr);
267 
268 	return transport;
269 }
270 
271 /* API 3.1.2 bind() - UDP Style Syntax
272  * The syntax of bind() is,
273  *
274  *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
275  *
276  *   sd      - the socket descriptor returned by socket().
277  *   addr    - the address structure (struct sockaddr_in or struct
278  *             sockaddr_in6 [RFC 2553]),
279  *   addr_len - the size of the address structure.
280  */
281 SCTP_STATIC int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
282 {
283 	int retval = 0;
284 
285 	sctp_lock_sock(sk);
286 
287 	SCTP_DEBUG_PRINTK("sctp_bind(sk: %p, addr: %p, addr_len: %d)\n",
288 			  sk, addr, addr_len);
289 
290 	/* Disallow binding twice. */
291 	if (!sctp_sk(sk)->ep->base.bind_addr.port)
292 		retval = sctp_do_bind(sk, (union sctp_addr *)addr,
293 				      addr_len);
294 	else
295 		retval = -EINVAL;
296 
297 	sctp_release_sock(sk);
298 
299 	return retval;
300 }
301 
302 static long sctp_get_port_local(struct sock *, union sctp_addr *);
303 
304 /* Verify this is a valid sockaddr. */
305 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
306 					union sctp_addr *addr, int len)
307 {
308 	struct sctp_af *af;
309 
310 	/* Check minimum size.  */
311 	if (len < sizeof (struct sockaddr))
312 		return NULL;
313 
314 	/* V4 mapped address are really of AF_INET family */
315 	if (addr->sa.sa_family == AF_INET6 &&
316 	    ipv6_addr_v4mapped(&addr->v6.sin6_addr)) {
317 		if (!opt->pf->af_supported(AF_INET, opt))
318 			return NULL;
319 	} else {
320 		/* Does this PF support this AF? */
321 		if (!opt->pf->af_supported(addr->sa.sa_family, opt))
322 			return NULL;
323 	}
324 
325 	/* If we get this far, af is valid. */
326 	af = sctp_get_af_specific(addr->sa.sa_family);
327 
328 	if (len < af->sockaddr_len)
329 		return NULL;
330 
331 	return af;
332 }
333 
334 /* Bind a local address either to an endpoint or to an association.  */
335 SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
336 {
337 	struct sctp_sock *sp = sctp_sk(sk);
338 	struct sctp_endpoint *ep = sp->ep;
339 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
340 	struct sctp_af *af;
341 	unsigned short snum;
342 	int ret = 0;
343 
344 	/* Common sockaddr verification. */
345 	af = sctp_sockaddr_af(sp, addr, len);
346 	if (!af) {
347 		SCTP_DEBUG_PRINTK("sctp_do_bind(sk: %p, newaddr: %p, len: %d) EINVAL\n",
348 				  sk, addr, len);
349 		return -EINVAL;
350 	}
351 
352 	snum = ntohs(addr->v4.sin_port);
353 
354 	SCTP_DEBUG_PRINTK_IPADDR("sctp_do_bind(sk: %p, new addr: ",
355 				 ", port: %d, new port: %d, len: %d)\n",
356 				 sk,
357 				 addr,
358 				 bp->port, snum,
359 				 len);
360 
361 	/* PF specific bind() address verification. */
362 	if (!sp->pf->bind_verify(sp, addr))
363 		return -EADDRNOTAVAIL;
364 
365 	/* We must either be unbound, or bind to the same port.
366 	 * It's OK to allow 0 ports if we are already bound.
367 	 * We'll just inhert an already bound port in this case
368 	 */
369 	if (bp->port) {
370 		if (!snum)
371 			snum = bp->port;
372 		else if (snum != bp->port) {
373 			SCTP_DEBUG_PRINTK("sctp_do_bind:"
374 				  " New port %d does not match existing port "
375 				  "%d.\n", snum, bp->port);
376 			return -EINVAL;
377 		}
378 	}
379 
380 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
381 		return -EACCES;
382 
383 	/* See if the address matches any of the addresses we may have
384 	 * already bound before checking against other endpoints.
385 	 */
386 	if (sctp_bind_addr_match(bp, addr, sp))
387 		return -EINVAL;
388 
389 	/* Make sure we are allowed to bind here.
390 	 * The function sctp_get_port_local() does duplicate address
391 	 * detection.
392 	 */
393 	addr->v4.sin_port = htons(snum);
394 	if ((ret = sctp_get_port_local(sk, addr))) {
395 		return -EADDRINUSE;
396 	}
397 
398 	/* Refresh ephemeral port.  */
399 	if (!bp->port)
400 		bp->port = inet_sk(sk)->inet_num;
401 
402 	/* Add the address to the bind address list.
403 	 * Use GFP_ATOMIC since BHs will be disabled.
404 	 */
405 	ret = sctp_add_bind_addr(bp, addr, SCTP_ADDR_SRC, GFP_ATOMIC);
406 
407 	/* Copy back into socket for getsockname() use. */
408 	if (!ret) {
409 		inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num);
410 		af->to_sk_saddr(addr, sk);
411 	}
412 
413 	return ret;
414 }
415 
416  /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
417  *
418  * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
419  * at any one time.  If a sender, after sending an ASCONF chunk, decides
420  * it needs to transfer another ASCONF Chunk, it MUST wait until the
421  * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
422  * subsequent ASCONF. Note this restriction binds each side, so at any
423  * time two ASCONF may be in-transit on any given association (one sent
424  * from each endpoint).
425  */
426 static int sctp_send_asconf(struct sctp_association *asoc,
427 			    struct sctp_chunk *chunk)
428 {
429 	int		retval = 0;
430 
431 	/* If there is an outstanding ASCONF chunk, queue it for later
432 	 * transmission.
433 	 */
434 	if (asoc->addip_last_asconf) {
435 		list_add_tail(&chunk->list, &asoc->addip_chunk_list);
436 		goto out;
437 	}
438 
439 	/* Hold the chunk until an ASCONF_ACK is received. */
440 	sctp_chunk_hold(chunk);
441 	retval = sctp_primitive_ASCONF(asoc, chunk);
442 	if (retval)
443 		sctp_chunk_free(chunk);
444 	else
445 		asoc->addip_last_asconf = chunk;
446 
447 out:
448 	return retval;
449 }
450 
451 /* Add a list of addresses as bind addresses to local endpoint or
452  * association.
453  *
454  * Basically run through each address specified in the addrs/addrcnt
455  * array/length pair, determine if it is IPv6 or IPv4 and call
456  * sctp_do_bind() on it.
457  *
458  * If any of them fails, then the operation will be reversed and the
459  * ones that were added will be removed.
460  *
461  * Only sctp_setsockopt_bindx() is supposed to call this function.
462  */
463 static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
464 {
465 	int cnt;
466 	int retval = 0;
467 	void *addr_buf;
468 	struct sockaddr *sa_addr;
469 	struct sctp_af *af;
470 
471 	SCTP_DEBUG_PRINTK("sctp_bindx_add (sk: %p, addrs: %p, addrcnt: %d)\n",
472 			  sk, addrs, addrcnt);
473 
474 	addr_buf = addrs;
475 	for (cnt = 0; cnt < addrcnt; cnt++) {
476 		/* The list may contain either IPv4 or IPv6 address;
477 		 * determine the address length for walking thru the list.
478 		 */
479 		sa_addr = (struct sockaddr *)addr_buf;
480 		af = sctp_get_af_specific(sa_addr->sa_family);
481 		if (!af) {
482 			retval = -EINVAL;
483 			goto err_bindx_add;
484 		}
485 
486 		retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
487 				      af->sockaddr_len);
488 
489 		addr_buf += af->sockaddr_len;
490 
491 err_bindx_add:
492 		if (retval < 0) {
493 			/* Failed. Cleanup the ones that have been added */
494 			if (cnt > 0)
495 				sctp_bindx_rem(sk, addrs, cnt);
496 			return retval;
497 		}
498 	}
499 
500 	return retval;
501 }
502 
503 /* Send an ASCONF chunk with Add IP address parameters to all the peers of the
504  * associations that are part of the endpoint indicating that a list of local
505  * addresses are added to the endpoint.
506  *
507  * If any of the addresses is already in the bind address list of the
508  * association, we do not send the chunk for that association.  But it will not
509  * affect other associations.
510  *
511  * Only sctp_setsockopt_bindx() is supposed to call this function.
512  */
513 static int sctp_send_asconf_add_ip(struct sock		*sk,
514 				   struct sockaddr	*addrs,
515 				   int 			addrcnt)
516 {
517 	struct sctp_sock		*sp;
518 	struct sctp_endpoint		*ep;
519 	struct sctp_association		*asoc;
520 	struct sctp_bind_addr		*bp;
521 	struct sctp_chunk		*chunk;
522 	struct sctp_sockaddr_entry	*laddr;
523 	union sctp_addr			*addr;
524 	union sctp_addr			saveaddr;
525 	void				*addr_buf;
526 	struct sctp_af			*af;
527 	struct list_head		*p;
528 	int 				i;
529 	int 				retval = 0;
530 
531 	if (!sctp_addip_enable)
532 		return retval;
533 
534 	sp = sctp_sk(sk);
535 	ep = sp->ep;
536 
537 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
538 			  __func__, sk, addrs, addrcnt);
539 
540 	list_for_each_entry(asoc, &ep->asocs, asocs) {
541 
542 		if (!asoc->peer.asconf_capable)
543 			continue;
544 
545 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
546 			continue;
547 
548 		if (!sctp_state(asoc, ESTABLISHED))
549 			continue;
550 
551 		/* Check if any address in the packed array of addresses is
552 		 * in the bind address list of the association. If so,
553 		 * do not send the asconf chunk to its peer, but continue with
554 		 * other associations.
555 		 */
556 		addr_buf = addrs;
557 		for (i = 0; i < addrcnt; i++) {
558 			addr = (union sctp_addr *)addr_buf;
559 			af = sctp_get_af_specific(addr->v4.sin_family);
560 			if (!af) {
561 				retval = -EINVAL;
562 				goto out;
563 			}
564 
565 			if (sctp_assoc_lookup_laddr(asoc, addr))
566 				break;
567 
568 			addr_buf += af->sockaddr_len;
569 		}
570 		if (i < addrcnt)
571 			continue;
572 
573 		/* Use the first valid address in bind addr list of
574 		 * association as Address Parameter of ASCONF CHUNK.
575 		 */
576 		bp = &asoc->base.bind_addr;
577 		p = bp->address_list.next;
578 		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
579 		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
580 						   addrcnt, SCTP_PARAM_ADD_IP);
581 		if (!chunk) {
582 			retval = -ENOMEM;
583 			goto out;
584 		}
585 
586 		retval = sctp_send_asconf(asoc, chunk);
587 		if (retval)
588 			goto out;
589 
590 		/* Add the new addresses to the bind address list with
591 		 * use_as_src set to 0.
592 		 */
593 		addr_buf = addrs;
594 		for (i = 0; i < addrcnt; i++) {
595 			addr = (union sctp_addr *)addr_buf;
596 			af = sctp_get_af_specific(addr->v4.sin_family);
597 			memcpy(&saveaddr, addr, af->sockaddr_len);
598 			retval = sctp_add_bind_addr(bp, &saveaddr,
599 						    SCTP_ADDR_NEW, GFP_ATOMIC);
600 			addr_buf += af->sockaddr_len;
601 		}
602 	}
603 
604 out:
605 	return retval;
606 }
607 
608 /* Remove a list of addresses from bind addresses list.  Do not remove the
609  * last address.
610  *
611  * Basically run through each address specified in the addrs/addrcnt
612  * array/length pair, determine if it is IPv6 or IPv4 and call
613  * sctp_del_bind() on it.
614  *
615  * If any of them fails, then the operation will be reversed and the
616  * ones that were removed will be added back.
617  *
618  * At least one address has to be left; if only one address is
619  * available, the operation will return -EBUSY.
620  *
621  * Only sctp_setsockopt_bindx() is supposed to call this function.
622  */
623 static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
624 {
625 	struct sctp_sock *sp = sctp_sk(sk);
626 	struct sctp_endpoint *ep = sp->ep;
627 	int cnt;
628 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
629 	int retval = 0;
630 	void *addr_buf;
631 	union sctp_addr *sa_addr;
632 	struct sctp_af *af;
633 
634 	SCTP_DEBUG_PRINTK("sctp_bindx_rem (sk: %p, addrs: %p, addrcnt: %d)\n",
635 			  sk, addrs, addrcnt);
636 
637 	addr_buf = addrs;
638 	for (cnt = 0; cnt < addrcnt; cnt++) {
639 		/* If the bind address list is empty or if there is only one
640 		 * bind address, there is nothing more to be removed (we need
641 		 * at least one address here).
642 		 */
643 		if (list_empty(&bp->address_list) ||
644 		    (sctp_list_single_entry(&bp->address_list))) {
645 			retval = -EBUSY;
646 			goto err_bindx_rem;
647 		}
648 
649 		sa_addr = (union sctp_addr *)addr_buf;
650 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
651 		if (!af) {
652 			retval = -EINVAL;
653 			goto err_bindx_rem;
654 		}
655 
656 		if (!af->addr_valid(sa_addr, sp, NULL)) {
657 			retval = -EADDRNOTAVAIL;
658 			goto err_bindx_rem;
659 		}
660 
661 		if (sa_addr->v4.sin_port &&
662 		    sa_addr->v4.sin_port != htons(bp->port)) {
663 			retval = -EINVAL;
664 			goto err_bindx_rem;
665 		}
666 
667 		if (!sa_addr->v4.sin_port)
668 			sa_addr->v4.sin_port = htons(bp->port);
669 
670 		/* FIXME - There is probably a need to check if sk->sk_saddr and
671 		 * sk->sk_rcv_addr are currently set to one of the addresses to
672 		 * be removed. This is something which needs to be looked into
673 		 * when we are fixing the outstanding issues with multi-homing
674 		 * socket routing and failover schemes. Refer to comments in
675 		 * sctp_do_bind(). -daisy
676 		 */
677 		retval = sctp_del_bind_addr(bp, sa_addr);
678 
679 		addr_buf += af->sockaddr_len;
680 err_bindx_rem:
681 		if (retval < 0) {
682 			/* Failed. Add the ones that has been removed back */
683 			if (cnt > 0)
684 				sctp_bindx_add(sk, addrs, cnt);
685 			return retval;
686 		}
687 	}
688 
689 	return retval;
690 }
691 
692 /* Send an ASCONF chunk with Delete IP address parameters to all the peers of
693  * the associations that are part of the endpoint indicating that a list of
694  * local addresses are removed from the endpoint.
695  *
696  * If any of the addresses is already in the bind address list of the
697  * association, we do not send the chunk for that association.  But it will not
698  * affect other associations.
699  *
700  * Only sctp_setsockopt_bindx() is supposed to call this function.
701  */
702 static int sctp_send_asconf_del_ip(struct sock		*sk,
703 				   struct sockaddr	*addrs,
704 				   int			addrcnt)
705 {
706 	struct sctp_sock	*sp;
707 	struct sctp_endpoint	*ep;
708 	struct sctp_association	*asoc;
709 	struct sctp_transport	*transport;
710 	struct sctp_bind_addr	*bp;
711 	struct sctp_chunk	*chunk;
712 	union sctp_addr		*laddr;
713 	void			*addr_buf;
714 	struct sctp_af		*af;
715 	struct sctp_sockaddr_entry *saddr;
716 	int 			i;
717 	int 			retval = 0;
718 
719 	if (!sctp_addip_enable)
720 		return retval;
721 
722 	sp = sctp_sk(sk);
723 	ep = sp->ep;
724 
725 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
726 			  __func__, sk, addrs, addrcnt);
727 
728 	list_for_each_entry(asoc, &ep->asocs, asocs) {
729 
730 		if (!asoc->peer.asconf_capable)
731 			continue;
732 
733 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
734 			continue;
735 
736 		if (!sctp_state(asoc, ESTABLISHED))
737 			continue;
738 
739 		/* Check if any address in the packed array of addresses is
740 		 * not present in the bind address list of the association.
741 		 * If so, do not send the asconf chunk to its peer, but
742 		 * continue with other associations.
743 		 */
744 		addr_buf = addrs;
745 		for (i = 0; i < addrcnt; i++) {
746 			laddr = (union sctp_addr *)addr_buf;
747 			af = sctp_get_af_specific(laddr->v4.sin_family);
748 			if (!af) {
749 				retval = -EINVAL;
750 				goto out;
751 			}
752 
753 			if (!sctp_assoc_lookup_laddr(asoc, laddr))
754 				break;
755 
756 			addr_buf += af->sockaddr_len;
757 		}
758 		if (i < addrcnt)
759 			continue;
760 
761 		/* Find one address in the association's bind address list
762 		 * that is not in the packed array of addresses. This is to
763 		 * make sure that we do not delete all the addresses in the
764 		 * association.
765 		 */
766 		bp = &asoc->base.bind_addr;
767 		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
768 					       addrcnt, sp);
769 		if (!laddr)
770 			continue;
771 
772 		/* We do not need RCU protection throughout this loop
773 		 * because this is done under a socket lock from the
774 		 * setsockopt call.
775 		 */
776 		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
777 						   SCTP_PARAM_DEL_IP);
778 		if (!chunk) {
779 			retval = -ENOMEM;
780 			goto out;
781 		}
782 
783 		/* Reset use_as_src flag for the addresses in the bind address
784 		 * list that are to be deleted.
785 		 */
786 		addr_buf = addrs;
787 		for (i = 0; i < addrcnt; i++) {
788 			laddr = (union sctp_addr *)addr_buf;
789 			af = sctp_get_af_specific(laddr->v4.sin_family);
790 			list_for_each_entry(saddr, &bp->address_list, list) {
791 				if (sctp_cmp_addr_exact(&saddr->a, laddr))
792 					saddr->state = SCTP_ADDR_DEL;
793 			}
794 			addr_buf += af->sockaddr_len;
795 		}
796 
797 		/* Update the route and saddr entries for all the transports
798 		 * as some of the addresses in the bind address list are
799 		 * about to be deleted and cannot be used as source addresses.
800 		 */
801 		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
802 					transports) {
803 			dst_release(transport->dst);
804 			sctp_transport_route(transport, NULL,
805 					     sctp_sk(asoc->base.sk));
806 		}
807 
808 		retval = sctp_send_asconf(asoc, chunk);
809 	}
810 out:
811 	return retval;
812 }
813 
814 /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
815  *
816  * API 8.1
817  * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt,
818  *                int flags);
819  *
820  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
821  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
822  * or IPv6 addresses.
823  *
824  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
825  * Section 3.1.2 for this usage.
826  *
827  * addrs is a pointer to an array of one or more socket addresses. Each
828  * address is contained in its appropriate structure (i.e. struct
829  * sockaddr_in or struct sockaddr_in6) the family of the address type
830  * must be used to distinguish the address length (note that this
831  * representation is termed a "packed array" of addresses). The caller
832  * specifies the number of addresses in the array with addrcnt.
833  *
834  * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns
835  * -1, and sets errno to the appropriate error code.
836  *
837  * For SCTP, the port given in each socket address must be the same, or
838  * sctp_bindx() will fail, setting errno to EINVAL.
839  *
840  * The flags parameter is formed from the bitwise OR of zero or more of
841  * the following currently defined flags:
842  *
843  * SCTP_BINDX_ADD_ADDR
844  *
845  * SCTP_BINDX_REM_ADDR
846  *
847  * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
848  * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given
849  * addresses from the association. The two flags are mutually exclusive;
850  * if both are given, sctp_bindx() will fail with EINVAL. A caller may
851  * not remove all addresses from an association; sctp_bindx() will
852  * reject such an attempt with EINVAL.
853  *
854  * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
855  * additional addresses with an endpoint after calling bind().  Or use
856  * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
857  * socket is associated with so that no new association accepted will be
858  * associated with those addresses. If the endpoint supports dynamic
859  * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
860  * endpoint to send the appropriate message to the peer to change the
861  * peers address lists.
862  *
863  * Adding and removing addresses from a connected association is
864  * optional functionality. Implementations that do not support this
865  * functionality should return EOPNOTSUPP.
866  *
867  * Basically do nothing but copying the addresses from user to kernel
868  * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
869  * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
870  * from userspace.
871  *
872  * We don't use copy_from_user() for optimization: we first do the
873  * sanity checks (buffer size -fast- and access check-healthy
874  * pointer); if all of those succeed, then we can alloc the memory
875  * (expensive operation) needed to copy the data to kernel. Then we do
876  * the copying without checking the user space area
877  * (__copy_from_user()).
878  *
879  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
880  * it.
881  *
882  * sk        The sk of the socket
883  * addrs     The pointer to the addresses in user land
884  * addrssize Size of the addrs buffer
885  * op        Operation to perform (add or remove, see the flags of
886  *           sctp_bindx)
887  *
888  * Returns 0 if ok, <0 errno code on error.
889  */
890 SCTP_STATIC int sctp_setsockopt_bindx(struct sock* sk,
891 				      struct sockaddr __user *addrs,
892 				      int addrs_size, int op)
893 {
894 	struct sockaddr *kaddrs;
895 	int err;
896 	int addrcnt = 0;
897 	int walk_size = 0;
898 	struct sockaddr *sa_addr;
899 	void *addr_buf;
900 	struct sctp_af *af;
901 
902 	SCTP_DEBUG_PRINTK("sctp_setsocktopt_bindx: sk %p addrs %p"
903 			  " addrs_size %d opt %d\n", sk, addrs, addrs_size, op);
904 
905 	if (unlikely(addrs_size <= 0))
906 		return -EINVAL;
907 
908 	/* Check the user passed a healthy pointer.  */
909 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
910 		return -EFAULT;
911 
912 	/* Alloc space for the address array in kernel memory.  */
913 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
914 	if (unlikely(!kaddrs))
915 		return -ENOMEM;
916 
917 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
918 		kfree(kaddrs);
919 		return -EFAULT;
920 	}
921 
922 	/* Walk through the addrs buffer and count the number of addresses. */
923 	addr_buf = kaddrs;
924 	while (walk_size < addrs_size) {
925 		if (walk_size + sizeof(sa_family_t) > addrs_size) {
926 			kfree(kaddrs);
927 			return -EINVAL;
928 		}
929 
930 		sa_addr = (struct sockaddr *)addr_buf;
931 		af = sctp_get_af_specific(sa_addr->sa_family);
932 
933 		/* If the address family is not supported or if this address
934 		 * causes the address buffer to overflow return EINVAL.
935 		 */
936 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
937 			kfree(kaddrs);
938 			return -EINVAL;
939 		}
940 		addrcnt++;
941 		addr_buf += af->sockaddr_len;
942 		walk_size += af->sockaddr_len;
943 	}
944 
945 	/* Do the work. */
946 	switch (op) {
947 	case SCTP_BINDX_ADD_ADDR:
948 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
949 		if (err)
950 			goto out;
951 		err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
952 		break;
953 
954 	case SCTP_BINDX_REM_ADDR:
955 		err = sctp_bindx_rem(sk, kaddrs, addrcnt);
956 		if (err)
957 			goto out;
958 		err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
959 		break;
960 
961 	default:
962 		err = -EINVAL;
963 		break;
964 	}
965 
966 out:
967 	kfree(kaddrs);
968 
969 	return err;
970 }
971 
972 /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
973  *
974  * Common routine for handling connect() and sctp_connectx().
975  * Connect will come in with just a single address.
976  */
977 static int __sctp_connect(struct sock* sk,
978 			  struct sockaddr *kaddrs,
979 			  int addrs_size,
980 			  sctp_assoc_t *assoc_id)
981 {
982 	struct sctp_sock *sp;
983 	struct sctp_endpoint *ep;
984 	struct sctp_association *asoc = NULL;
985 	struct sctp_association *asoc2;
986 	struct sctp_transport *transport;
987 	union sctp_addr to;
988 	struct sctp_af *af;
989 	sctp_scope_t scope;
990 	long timeo;
991 	int err = 0;
992 	int addrcnt = 0;
993 	int walk_size = 0;
994 	union sctp_addr *sa_addr = NULL;
995 	void *addr_buf;
996 	unsigned short port;
997 	unsigned int f_flags = 0;
998 
999 	sp = sctp_sk(sk);
1000 	ep = sp->ep;
1001 
1002 	/* connect() cannot be done on a socket that is already in ESTABLISHED
1003 	 * state - UDP-style peeled off socket or a TCP-style socket that
1004 	 * is already connected.
1005 	 * It cannot be done even on a TCP-style listening socket.
1006 	 */
1007 	if (sctp_sstate(sk, ESTABLISHED) ||
1008 	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
1009 		err = -EISCONN;
1010 		goto out_free;
1011 	}
1012 
1013 	/* Walk through the addrs buffer and count the number of addresses. */
1014 	addr_buf = kaddrs;
1015 	while (walk_size < addrs_size) {
1016 		if (walk_size + sizeof(sa_family_t) > addrs_size) {
1017 			err = -EINVAL;
1018 			goto out_free;
1019 		}
1020 
1021 		sa_addr = (union sctp_addr *)addr_buf;
1022 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
1023 
1024 		/* If the address family is not supported or if this address
1025 		 * causes the address buffer to overflow return EINVAL.
1026 		 */
1027 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1028 			err = -EINVAL;
1029 			goto out_free;
1030 		}
1031 
1032 		port = ntohs(sa_addr->v4.sin_port);
1033 
1034 		/* Save current address so we can work with it */
1035 		memcpy(&to, sa_addr, af->sockaddr_len);
1036 
1037 		err = sctp_verify_addr(sk, &to, af->sockaddr_len);
1038 		if (err)
1039 			goto out_free;
1040 
1041 		/* Make sure the destination port is correctly set
1042 		 * in all addresses.
1043 		 */
1044 		if (asoc && asoc->peer.port && asoc->peer.port != port)
1045 			goto out_free;
1046 
1047 
1048 		/* Check if there already is a matching association on the
1049 		 * endpoint (other than the one created here).
1050 		 */
1051 		asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1052 		if (asoc2 && asoc2 != asoc) {
1053 			if (asoc2->state >= SCTP_STATE_ESTABLISHED)
1054 				err = -EISCONN;
1055 			else
1056 				err = -EALREADY;
1057 			goto out_free;
1058 		}
1059 
1060 		/* If we could not find a matching association on the endpoint,
1061 		 * make sure that there is no peeled-off association matching
1062 		 * the peer address even on another socket.
1063 		 */
1064 		if (sctp_endpoint_is_peeled_off(ep, &to)) {
1065 			err = -EADDRNOTAVAIL;
1066 			goto out_free;
1067 		}
1068 
1069 		if (!asoc) {
1070 			/* If a bind() or sctp_bindx() is not called prior to
1071 			 * an sctp_connectx() call, the system picks an
1072 			 * ephemeral port and will choose an address set
1073 			 * equivalent to binding with a wildcard address.
1074 			 */
1075 			if (!ep->base.bind_addr.port) {
1076 				if (sctp_autobind(sk)) {
1077 					err = -EAGAIN;
1078 					goto out_free;
1079 				}
1080 			} else {
1081 				/*
1082 				 * If an unprivileged user inherits a 1-many
1083 				 * style socket with open associations on a
1084 				 * privileged port, it MAY be permitted to
1085 				 * accept new associations, but it SHOULD NOT
1086 				 * be permitted to open new associations.
1087 				 */
1088 				if (ep->base.bind_addr.port < PROT_SOCK &&
1089 				    !capable(CAP_NET_BIND_SERVICE)) {
1090 					err = -EACCES;
1091 					goto out_free;
1092 				}
1093 			}
1094 
1095 			scope = sctp_scope(&to);
1096 			asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1097 			if (!asoc) {
1098 				err = -ENOMEM;
1099 				goto out_free;
1100 			}
1101 
1102 			err = sctp_assoc_set_bind_addr_from_ep(asoc, scope,
1103 							      GFP_KERNEL);
1104 			if (err < 0) {
1105 				goto out_free;
1106 			}
1107 
1108 		}
1109 
1110 		/* Prime the peer's transport structures.  */
1111 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL,
1112 						SCTP_UNKNOWN);
1113 		if (!transport) {
1114 			err = -ENOMEM;
1115 			goto out_free;
1116 		}
1117 
1118 		addrcnt++;
1119 		addr_buf += af->sockaddr_len;
1120 		walk_size += af->sockaddr_len;
1121 	}
1122 
1123 	/* In case the user of sctp_connectx() wants an association
1124 	 * id back, assign one now.
1125 	 */
1126 	if (assoc_id) {
1127 		err = sctp_assoc_set_id(asoc, GFP_KERNEL);
1128 		if (err < 0)
1129 			goto out_free;
1130 	}
1131 
1132 	err = sctp_primitive_ASSOCIATE(asoc, NULL);
1133 	if (err < 0) {
1134 		goto out_free;
1135 	}
1136 
1137 	/* Initialize sk's dport and daddr for getpeername() */
1138 	inet_sk(sk)->inet_dport = htons(asoc->peer.port);
1139 	af = sctp_get_af_specific(sa_addr->sa.sa_family);
1140 	af->to_sk_daddr(sa_addr, sk);
1141 	sk->sk_err = 0;
1142 
1143 	/* in-kernel sockets don't generally have a file allocated to them
1144 	 * if all they do is call sock_create_kern().
1145 	 */
1146 	if (sk->sk_socket->file)
1147 		f_flags = sk->sk_socket->file->f_flags;
1148 
1149 	timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK);
1150 
1151 	err = sctp_wait_for_connect(asoc, &timeo);
1152 	if ((err == 0 || err == -EINPROGRESS) && assoc_id)
1153 		*assoc_id = asoc->assoc_id;
1154 
1155 	/* Don't free association on exit. */
1156 	asoc = NULL;
1157 
1158 out_free:
1159 
1160 	SCTP_DEBUG_PRINTK("About to exit __sctp_connect() free asoc: %p"
1161 			  " kaddrs: %p err: %d\n",
1162 			  asoc, kaddrs, err);
1163 	if (asoc)
1164 		sctp_association_free(asoc);
1165 	return err;
1166 }
1167 
1168 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
1169  *
1170  * API 8.9
1171  * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt,
1172  * 			sctp_assoc_t *asoc);
1173  *
1174  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
1175  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
1176  * or IPv6 addresses.
1177  *
1178  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
1179  * Section 3.1.2 for this usage.
1180  *
1181  * addrs is a pointer to an array of one or more socket addresses. Each
1182  * address is contained in its appropriate structure (i.e. struct
1183  * sockaddr_in or struct sockaddr_in6) the family of the address type
1184  * must be used to distengish the address length (note that this
1185  * representation is termed a "packed array" of addresses). The caller
1186  * specifies the number of addresses in the array with addrcnt.
1187  *
1188  * On success, sctp_connectx() returns 0. It also sets the assoc_id to
1189  * the association id of the new association.  On failure, sctp_connectx()
1190  * returns -1, and sets errno to the appropriate error code.  The assoc_id
1191  * is not touched by the kernel.
1192  *
1193  * For SCTP, the port given in each socket address must be the same, or
1194  * sctp_connectx() will fail, setting errno to EINVAL.
1195  *
1196  * An application can use sctp_connectx to initiate an association with
1197  * an endpoint that is multi-homed.  Much like sctp_bindx() this call
1198  * allows a caller to specify multiple addresses at which a peer can be
1199  * reached.  The way the SCTP stack uses the list of addresses to set up
1200  * the association is implementation dependent.  This function only
1201  * specifies that the stack will try to make use of all the addresses in
1202  * the list when needed.
1203  *
1204  * Note that the list of addresses passed in is only used for setting up
1205  * the association.  It does not necessarily equal the set of addresses
1206  * the peer uses for the resulting association.  If the caller wants to
1207  * find out the set of peer addresses, it must use sctp_getpaddrs() to
1208  * retrieve them after the association has been set up.
1209  *
1210  * Basically do nothing but copying the addresses from user to kernel
1211  * land and invoking either sctp_connectx(). This is used for tunneling
1212  * the sctp_connectx() request through sctp_setsockopt() from userspace.
1213  *
1214  * We don't use copy_from_user() for optimization: we first do the
1215  * sanity checks (buffer size -fast- and access check-healthy
1216  * pointer); if all of those succeed, then we can alloc the memory
1217  * (expensive operation) needed to copy the data to kernel. Then we do
1218  * the copying without checking the user space area
1219  * (__copy_from_user()).
1220  *
1221  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
1222  * it.
1223  *
1224  * sk        The sk of the socket
1225  * addrs     The pointer to the addresses in user land
1226  * addrssize Size of the addrs buffer
1227  *
1228  * Returns >=0 if ok, <0 errno code on error.
1229  */
1230 SCTP_STATIC int __sctp_setsockopt_connectx(struct sock* sk,
1231 				      struct sockaddr __user *addrs,
1232 				      int addrs_size,
1233 				      sctp_assoc_t *assoc_id)
1234 {
1235 	int err = 0;
1236 	struct sockaddr *kaddrs;
1237 
1238 	SCTP_DEBUG_PRINTK("%s - sk %p addrs %p addrs_size %d\n",
1239 			  __func__, sk, addrs, addrs_size);
1240 
1241 	if (unlikely(addrs_size <= 0))
1242 		return -EINVAL;
1243 
1244 	/* Check the user passed a healthy pointer.  */
1245 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
1246 		return -EFAULT;
1247 
1248 	/* Alloc space for the address array in kernel memory.  */
1249 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
1250 	if (unlikely(!kaddrs))
1251 		return -ENOMEM;
1252 
1253 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
1254 		err = -EFAULT;
1255 	} else {
1256 		err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
1257 	}
1258 
1259 	kfree(kaddrs);
1260 
1261 	return err;
1262 }
1263 
1264 /*
1265  * This is an older interface.  It's kept for backward compatibility
1266  * to the option that doesn't provide association id.
1267  */
1268 SCTP_STATIC int sctp_setsockopt_connectx_old(struct sock* sk,
1269 				      struct sockaddr __user *addrs,
1270 				      int addrs_size)
1271 {
1272 	return __sctp_setsockopt_connectx(sk, addrs, addrs_size, NULL);
1273 }
1274 
1275 /*
1276  * New interface for the API.  The since the API is done with a socket
1277  * option, to make it simple we feed back the association id is as a return
1278  * indication to the call.  Error is always negative and association id is
1279  * always positive.
1280  */
1281 SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
1282 				      struct sockaddr __user *addrs,
1283 				      int addrs_size)
1284 {
1285 	sctp_assoc_t assoc_id = 0;
1286 	int err = 0;
1287 
1288 	err = __sctp_setsockopt_connectx(sk, addrs, addrs_size, &assoc_id);
1289 
1290 	if (err)
1291 		return err;
1292 	else
1293 		return assoc_id;
1294 }
1295 
1296 /*
1297  * New (hopefully final) interface for the API.
1298  * We use the sctp_getaddrs_old structure so that use-space library
1299  * can avoid any unnecessary allocations.   The only defferent part
1300  * is that we store the actual length of the address buffer into the
1301  * addrs_num structure member.  That way we can re-use the existing
1302  * code.
1303  */
1304 SCTP_STATIC int sctp_getsockopt_connectx3(struct sock* sk, int len,
1305 					char __user *optval,
1306 					int __user *optlen)
1307 {
1308 	struct sctp_getaddrs_old param;
1309 	sctp_assoc_t assoc_id = 0;
1310 	int err = 0;
1311 
1312 	if (len < sizeof(param))
1313 		return -EINVAL;
1314 
1315 	if (copy_from_user(&param, optval, sizeof(param)))
1316 		return -EFAULT;
1317 
1318 	err = __sctp_setsockopt_connectx(sk,
1319 			(struct sockaddr __user *)param.addrs,
1320 			param.addr_num, &assoc_id);
1321 
1322 	if (err == 0 || err == -EINPROGRESS) {
1323 		if (copy_to_user(optval, &assoc_id, sizeof(assoc_id)))
1324 			return -EFAULT;
1325 		if (put_user(sizeof(assoc_id), optlen))
1326 			return -EFAULT;
1327 	}
1328 
1329 	return err;
1330 }
1331 
1332 /* API 3.1.4 close() - UDP Style Syntax
1333  * Applications use close() to perform graceful shutdown (as described in
1334  * Section 10.1 of [SCTP]) on ALL the associations currently represented
1335  * by a UDP-style socket.
1336  *
1337  * The syntax is
1338  *
1339  *   ret = close(int sd);
1340  *
1341  *   sd      - the socket descriptor of the associations to be closed.
1342  *
1343  * To gracefully shutdown a specific association represented by the
1344  * UDP-style socket, an application should use the sendmsg() call,
1345  * passing no user data, but including the appropriate flag in the
1346  * ancillary data (see Section xxxx).
1347  *
1348  * If sd in the close() call is a branched-off socket representing only
1349  * one association, the shutdown is performed on that association only.
1350  *
1351  * 4.1.6 close() - TCP Style Syntax
1352  *
1353  * Applications use close() to gracefully close down an association.
1354  *
1355  * The syntax is:
1356  *
1357  *    int close(int sd);
1358  *
1359  *      sd      - the socket descriptor of the association to be closed.
1360  *
1361  * After an application calls close() on a socket descriptor, no further
1362  * socket operations will succeed on that descriptor.
1363  *
1364  * API 7.1.4 SO_LINGER
1365  *
1366  * An application using the TCP-style socket can use this option to
1367  * perform the SCTP ABORT primitive.  The linger option structure is:
1368  *
1369  *  struct  linger {
1370  *     int     l_onoff;                // option on/off
1371  *     int     l_linger;               // linger time
1372  * };
1373  *
1374  * To enable the option, set l_onoff to 1.  If the l_linger value is set
1375  * to 0, calling close() is the same as the ABORT primitive.  If the
1376  * value is set to a negative value, the setsockopt() call will return
1377  * an error.  If the value is set to a positive value linger_time, the
1378  * close() can be blocked for at most linger_time ms.  If the graceful
1379  * shutdown phase does not finish during this period, close() will
1380  * return but the graceful shutdown phase continues in the system.
1381  */
1382 SCTP_STATIC void sctp_close(struct sock *sk, long timeout)
1383 {
1384 	struct sctp_endpoint *ep;
1385 	struct sctp_association *asoc;
1386 	struct list_head *pos, *temp;
1387 
1388 	SCTP_DEBUG_PRINTK("sctp_close(sk: 0x%p, timeout:%ld)\n", sk, timeout);
1389 
1390 	sctp_lock_sock(sk);
1391 	sk->sk_shutdown = SHUTDOWN_MASK;
1392 	sk->sk_state = SCTP_SS_CLOSING;
1393 
1394 	ep = sctp_sk(sk)->ep;
1395 
1396 	/* Walk all associations on an endpoint.  */
1397 	list_for_each_safe(pos, temp, &ep->asocs) {
1398 		asoc = list_entry(pos, struct sctp_association, asocs);
1399 
1400 		if (sctp_style(sk, TCP)) {
1401 			/* A closed association can still be in the list if
1402 			 * it belongs to a TCP-style listening socket that is
1403 			 * not yet accepted. If so, free it. If not, send an
1404 			 * ABORT or SHUTDOWN based on the linger options.
1405 			 */
1406 			if (sctp_state(asoc, CLOSED)) {
1407 				sctp_unhash_established(asoc);
1408 				sctp_association_free(asoc);
1409 				continue;
1410 			}
1411 		}
1412 
1413 		if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
1414 			struct sctp_chunk *chunk;
1415 
1416 			chunk = sctp_make_abort_user(asoc, NULL, 0);
1417 			if (chunk)
1418 				sctp_primitive_ABORT(asoc, chunk);
1419 		} else
1420 			sctp_primitive_SHUTDOWN(asoc, NULL);
1421 	}
1422 
1423 	/* Clean up any skbs sitting on the receive queue.  */
1424 	sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
1425 	sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
1426 
1427 	/* On a TCP-style socket, block for at most linger_time if set. */
1428 	if (sctp_style(sk, TCP) && timeout)
1429 		sctp_wait_for_close(sk, timeout);
1430 
1431 	/* This will run the backlog queue.  */
1432 	sctp_release_sock(sk);
1433 
1434 	/* Supposedly, no process has access to the socket, but
1435 	 * the net layers still may.
1436 	 */
1437 	sctp_local_bh_disable();
1438 	sctp_bh_lock_sock(sk);
1439 
1440 	/* Hold the sock, since sk_common_release() will put sock_put()
1441 	 * and we have just a little more cleanup.
1442 	 */
1443 	sock_hold(sk);
1444 	sk_common_release(sk);
1445 
1446 	sctp_bh_unlock_sock(sk);
1447 	sctp_local_bh_enable();
1448 
1449 	sock_put(sk);
1450 
1451 	SCTP_DBG_OBJCNT_DEC(sock);
1452 }
1453 
1454 /* Handle EPIPE error. */
1455 static int sctp_error(struct sock *sk, int flags, int err)
1456 {
1457 	if (err == -EPIPE)
1458 		err = sock_error(sk) ? : -EPIPE;
1459 	if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
1460 		send_sig(SIGPIPE, current, 0);
1461 	return err;
1462 }
1463 
1464 /* API 3.1.3 sendmsg() - UDP Style Syntax
1465  *
1466  * An application uses sendmsg() and recvmsg() calls to transmit data to
1467  * and receive data from its peer.
1468  *
1469  *  ssize_t sendmsg(int socket, const struct msghdr *message,
1470  *                  int flags);
1471  *
1472  *  socket  - the socket descriptor of the endpoint.
1473  *  message - pointer to the msghdr structure which contains a single
1474  *            user message and possibly some ancillary data.
1475  *
1476  *            See Section 5 for complete description of the data
1477  *            structures.
1478  *
1479  *  flags   - flags sent or received with the user message, see Section
1480  *            5 for complete description of the flags.
1481  *
1482  * Note:  This function could use a rewrite especially when explicit
1483  * connect support comes in.
1484  */
1485 /* BUG:  We do not implement the equivalent of sk_stream_wait_memory(). */
1486 
1487 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
1488 
1489 SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
1490 			     struct msghdr *msg, size_t msg_len)
1491 {
1492 	struct sctp_sock *sp;
1493 	struct sctp_endpoint *ep;
1494 	struct sctp_association *new_asoc=NULL, *asoc=NULL;
1495 	struct sctp_transport *transport, *chunk_tp;
1496 	struct sctp_chunk *chunk;
1497 	union sctp_addr to;
1498 	struct sockaddr *msg_name = NULL;
1499 	struct sctp_sndrcvinfo default_sinfo;
1500 	struct sctp_sndrcvinfo *sinfo;
1501 	struct sctp_initmsg *sinit;
1502 	sctp_assoc_t associd = 0;
1503 	sctp_cmsgs_t cmsgs = { NULL };
1504 	int err;
1505 	sctp_scope_t scope;
1506 	long timeo;
1507 	__u16 sinfo_flags = 0;
1508 	struct sctp_datamsg *datamsg;
1509 	int msg_flags = msg->msg_flags;
1510 
1511 	SCTP_DEBUG_PRINTK("sctp_sendmsg(sk: %p, msg: %p, msg_len: %zu)\n",
1512 			  sk, msg, msg_len);
1513 
1514 	err = 0;
1515 	sp = sctp_sk(sk);
1516 	ep = sp->ep;
1517 
1518 	SCTP_DEBUG_PRINTK("Using endpoint: %p.\n", ep);
1519 
1520 	/* We cannot send a message over a TCP-style listening socket. */
1521 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) {
1522 		err = -EPIPE;
1523 		goto out_nounlock;
1524 	}
1525 
1526 	/* Parse out the SCTP CMSGs.  */
1527 	err = sctp_msghdr_parse(msg, &cmsgs);
1528 
1529 	if (err) {
1530 		SCTP_DEBUG_PRINTK("msghdr parse err = %x\n", err);
1531 		goto out_nounlock;
1532 	}
1533 
1534 	/* Fetch the destination address for this packet.  This
1535 	 * address only selects the association--it is not necessarily
1536 	 * the address we will send to.
1537 	 * For a peeled-off socket, msg_name is ignored.
1538 	 */
1539 	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
1540 		int msg_namelen = msg->msg_namelen;
1541 
1542 		err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
1543 				       msg_namelen);
1544 		if (err)
1545 			return err;
1546 
1547 		if (msg_namelen > sizeof(to))
1548 			msg_namelen = sizeof(to);
1549 		memcpy(&to, msg->msg_name, msg_namelen);
1550 		msg_name = msg->msg_name;
1551 	}
1552 
1553 	sinfo = cmsgs.info;
1554 	sinit = cmsgs.init;
1555 
1556 	/* Did the user specify SNDRCVINFO?  */
1557 	if (sinfo) {
1558 		sinfo_flags = sinfo->sinfo_flags;
1559 		associd = sinfo->sinfo_assoc_id;
1560 	}
1561 
1562 	SCTP_DEBUG_PRINTK("msg_len: %zu, sinfo_flags: 0x%x\n",
1563 			  msg_len, sinfo_flags);
1564 
1565 	/* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */
1566 	if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) {
1567 		err = -EINVAL;
1568 		goto out_nounlock;
1569 	}
1570 
1571 	/* If SCTP_EOF is set, no data can be sent. Disallow sending zero
1572 	 * length messages when SCTP_EOF|SCTP_ABORT is not set.
1573 	 * If SCTP_ABORT is set, the message length could be non zero with
1574 	 * the msg_iov set to the user abort reason.
1575 	 */
1576 	if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) ||
1577 	    (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) {
1578 		err = -EINVAL;
1579 		goto out_nounlock;
1580 	}
1581 
1582 	/* If SCTP_ADDR_OVER is set, there must be an address
1583 	 * specified in msg_name.
1584 	 */
1585 	if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) {
1586 		err = -EINVAL;
1587 		goto out_nounlock;
1588 	}
1589 
1590 	transport = NULL;
1591 
1592 	SCTP_DEBUG_PRINTK("About to look up association.\n");
1593 
1594 	sctp_lock_sock(sk);
1595 
1596 	/* If a msg_name has been specified, assume this is to be used.  */
1597 	if (msg_name) {
1598 		/* Look for a matching association on the endpoint. */
1599 		asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1600 		if (!asoc) {
1601 			/* If we could not find a matching association on the
1602 			 * endpoint, make sure that it is not a TCP-style
1603 			 * socket that already has an association or there is
1604 			 * no peeled-off association on another socket.
1605 			 */
1606 			if ((sctp_style(sk, TCP) &&
1607 			     sctp_sstate(sk, ESTABLISHED)) ||
1608 			    sctp_endpoint_is_peeled_off(ep, &to)) {
1609 				err = -EADDRNOTAVAIL;
1610 				goto out_unlock;
1611 			}
1612 		}
1613 	} else {
1614 		asoc = sctp_id2assoc(sk, associd);
1615 		if (!asoc) {
1616 			err = -EPIPE;
1617 			goto out_unlock;
1618 		}
1619 	}
1620 
1621 	if (asoc) {
1622 		SCTP_DEBUG_PRINTK("Just looked up association: %p.\n", asoc);
1623 
1624 		/* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED
1625 		 * socket that has an association in CLOSED state. This can
1626 		 * happen when an accepted socket has an association that is
1627 		 * already CLOSED.
1628 		 */
1629 		if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) {
1630 			err = -EPIPE;
1631 			goto out_unlock;
1632 		}
1633 
1634 		if (sinfo_flags & SCTP_EOF) {
1635 			SCTP_DEBUG_PRINTK("Shutting down association: %p\n",
1636 					  asoc);
1637 			sctp_primitive_SHUTDOWN(asoc, NULL);
1638 			err = 0;
1639 			goto out_unlock;
1640 		}
1641 		if (sinfo_flags & SCTP_ABORT) {
1642 
1643 			chunk = sctp_make_abort_user(asoc, msg, msg_len);
1644 			if (!chunk) {
1645 				err = -ENOMEM;
1646 				goto out_unlock;
1647 			}
1648 
1649 			SCTP_DEBUG_PRINTK("Aborting association: %p\n", asoc);
1650 			sctp_primitive_ABORT(asoc, chunk);
1651 			err = 0;
1652 			goto out_unlock;
1653 		}
1654 	}
1655 
1656 	/* Do we need to create the association?  */
1657 	if (!asoc) {
1658 		SCTP_DEBUG_PRINTK("There is no association yet.\n");
1659 
1660 		if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) {
1661 			err = -EINVAL;
1662 			goto out_unlock;
1663 		}
1664 
1665 		/* Check for invalid stream against the stream counts,
1666 		 * either the default or the user specified stream counts.
1667 		 */
1668 		if (sinfo) {
1669 			if (!sinit || (sinit && !sinit->sinit_num_ostreams)) {
1670 				/* Check against the defaults. */
1671 				if (sinfo->sinfo_stream >=
1672 				    sp->initmsg.sinit_num_ostreams) {
1673 					err = -EINVAL;
1674 					goto out_unlock;
1675 				}
1676 			} else {
1677 				/* Check against the requested.  */
1678 				if (sinfo->sinfo_stream >=
1679 				    sinit->sinit_num_ostreams) {
1680 					err = -EINVAL;
1681 					goto out_unlock;
1682 				}
1683 			}
1684 		}
1685 
1686 		/*
1687 		 * API 3.1.2 bind() - UDP Style Syntax
1688 		 * If a bind() or sctp_bindx() is not called prior to a
1689 		 * sendmsg() call that initiates a new association, the
1690 		 * system picks an ephemeral port and will choose an address
1691 		 * set equivalent to binding with a wildcard address.
1692 		 */
1693 		if (!ep->base.bind_addr.port) {
1694 			if (sctp_autobind(sk)) {
1695 				err = -EAGAIN;
1696 				goto out_unlock;
1697 			}
1698 		} else {
1699 			/*
1700 			 * If an unprivileged user inherits a one-to-many
1701 			 * style socket with open associations on a privileged
1702 			 * port, it MAY be permitted to accept new associations,
1703 			 * but it SHOULD NOT be permitted to open new
1704 			 * associations.
1705 			 */
1706 			if (ep->base.bind_addr.port < PROT_SOCK &&
1707 			    !capable(CAP_NET_BIND_SERVICE)) {
1708 				err = -EACCES;
1709 				goto out_unlock;
1710 			}
1711 		}
1712 
1713 		scope = sctp_scope(&to);
1714 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1715 		if (!new_asoc) {
1716 			err = -ENOMEM;
1717 			goto out_unlock;
1718 		}
1719 		asoc = new_asoc;
1720 		err = sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL);
1721 		if (err < 0) {
1722 			err = -ENOMEM;
1723 			goto out_free;
1724 		}
1725 
1726 		/* If the SCTP_INIT ancillary data is specified, set all
1727 		 * the association init values accordingly.
1728 		 */
1729 		if (sinit) {
1730 			if (sinit->sinit_num_ostreams) {
1731 				asoc->c.sinit_num_ostreams =
1732 					sinit->sinit_num_ostreams;
1733 			}
1734 			if (sinit->sinit_max_instreams) {
1735 				asoc->c.sinit_max_instreams =
1736 					sinit->sinit_max_instreams;
1737 			}
1738 			if (sinit->sinit_max_attempts) {
1739 				asoc->max_init_attempts
1740 					= sinit->sinit_max_attempts;
1741 			}
1742 			if (sinit->sinit_max_init_timeo) {
1743 				asoc->max_init_timeo =
1744 				 msecs_to_jiffies(sinit->sinit_max_init_timeo);
1745 			}
1746 		}
1747 
1748 		/* Prime the peer's transport structures.  */
1749 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN);
1750 		if (!transport) {
1751 			err = -ENOMEM;
1752 			goto out_free;
1753 		}
1754 	}
1755 
1756 	/* ASSERT: we have a valid association at this point.  */
1757 	SCTP_DEBUG_PRINTK("We have a valid association.\n");
1758 
1759 	if (!sinfo) {
1760 		/* If the user didn't specify SNDRCVINFO, make up one with
1761 		 * some defaults.
1762 		 */
1763 		memset(&default_sinfo, 0, sizeof(default_sinfo));
1764 		default_sinfo.sinfo_stream = asoc->default_stream;
1765 		default_sinfo.sinfo_flags = asoc->default_flags;
1766 		default_sinfo.sinfo_ppid = asoc->default_ppid;
1767 		default_sinfo.sinfo_context = asoc->default_context;
1768 		default_sinfo.sinfo_timetolive = asoc->default_timetolive;
1769 		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
1770 		sinfo = &default_sinfo;
1771 	}
1772 
1773 	/* API 7.1.7, the sndbuf size per association bounds the
1774 	 * maximum size of data that can be sent in a single send call.
1775 	 */
1776 	if (msg_len > sk->sk_sndbuf) {
1777 		err = -EMSGSIZE;
1778 		goto out_free;
1779 	}
1780 
1781 	if (asoc->pmtu_pending)
1782 		sctp_assoc_pending_pmtu(asoc);
1783 
1784 	/* If fragmentation is disabled and the message length exceeds the
1785 	 * association fragmentation point, return EMSGSIZE.  The I-D
1786 	 * does not specify what this error is, but this looks like
1787 	 * a great fit.
1788 	 */
1789 	if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
1790 		err = -EMSGSIZE;
1791 		goto out_free;
1792 	}
1793 
1794 	/* Check for invalid stream. */
1795 	if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) {
1796 		err = -EINVAL;
1797 		goto out_free;
1798 	}
1799 
1800 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1801 	if (!sctp_wspace(asoc)) {
1802 		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
1803 		if (err)
1804 			goto out_free;
1805 	}
1806 
1807 	/* If an address is passed with the sendto/sendmsg call, it is used
1808 	 * to override the primary destination address in the TCP model, or
1809 	 * when SCTP_ADDR_OVER flag is set in the UDP model.
1810 	 */
1811 	if ((sctp_style(sk, TCP) && msg_name) ||
1812 	    (sinfo_flags & SCTP_ADDR_OVER)) {
1813 		chunk_tp = sctp_assoc_lookup_paddr(asoc, &to);
1814 		if (!chunk_tp) {
1815 			err = -EINVAL;
1816 			goto out_free;
1817 		}
1818 	} else
1819 		chunk_tp = NULL;
1820 
1821 	/* Auto-connect, if we aren't connected already. */
1822 	if (sctp_state(asoc, CLOSED)) {
1823 		err = sctp_primitive_ASSOCIATE(asoc, NULL);
1824 		if (err < 0)
1825 			goto out_free;
1826 		SCTP_DEBUG_PRINTK("We associated primitively.\n");
1827 	}
1828 
1829 	/* Break the message into multiple chunks of maximum size. */
1830 	datamsg = sctp_datamsg_from_user(asoc, sinfo, msg, msg_len);
1831 	if (!datamsg) {
1832 		err = -ENOMEM;
1833 		goto out_free;
1834 	}
1835 
1836 	/* Now send the (possibly) fragmented message. */
1837 	list_for_each_entry(chunk, &datamsg->chunks, frag_list) {
1838 		sctp_chunk_hold(chunk);
1839 
1840 		/* Do accounting for the write space.  */
1841 		sctp_set_owner_w(chunk);
1842 
1843 		chunk->transport = chunk_tp;
1844 	}
1845 
1846 	/* Send it to the lower layers.  Note:  all chunks
1847 	 * must either fail or succeed.   The lower layer
1848 	 * works that way today.  Keep it that way or this
1849 	 * breaks.
1850 	 */
1851 	err = sctp_primitive_SEND(asoc, datamsg);
1852 	/* Did the lower layer accept the chunk? */
1853 	if (err)
1854 		sctp_datamsg_free(datamsg);
1855 	else
1856 		sctp_datamsg_put(datamsg);
1857 
1858 	SCTP_DEBUG_PRINTK("We sent primitively.\n");
1859 
1860 	if (err)
1861 		goto out_free;
1862 	else
1863 		err = msg_len;
1864 
1865 	/* If we are already past ASSOCIATE, the lower
1866 	 * layers are responsible for association cleanup.
1867 	 */
1868 	goto out_unlock;
1869 
1870 out_free:
1871 	if (new_asoc)
1872 		sctp_association_free(asoc);
1873 out_unlock:
1874 	sctp_release_sock(sk);
1875 
1876 out_nounlock:
1877 	return sctp_error(sk, msg_flags, err);
1878 
1879 #if 0
1880 do_sock_err:
1881 	if (msg_len)
1882 		err = msg_len;
1883 	else
1884 		err = sock_error(sk);
1885 	goto out;
1886 
1887 do_interrupted:
1888 	if (msg_len)
1889 		err = msg_len;
1890 	goto out;
1891 #endif /* 0 */
1892 }
1893 
1894 /* This is an extended version of skb_pull() that removes the data from the
1895  * start of a skb even when data is spread across the list of skb's in the
1896  * frag_list. len specifies the total amount of data that needs to be removed.
1897  * when 'len' bytes could be removed from the skb, it returns 0.
1898  * If 'len' exceeds the total skb length,  it returns the no. of bytes that
1899  * could not be removed.
1900  */
1901 static int sctp_skb_pull(struct sk_buff *skb, int len)
1902 {
1903 	struct sk_buff *list;
1904 	int skb_len = skb_headlen(skb);
1905 	int rlen;
1906 
1907 	if (len <= skb_len) {
1908 		__skb_pull(skb, len);
1909 		return 0;
1910 	}
1911 	len -= skb_len;
1912 	__skb_pull(skb, skb_len);
1913 
1914 	skb_walk_frags(skb, list) {
1915 		rlen = sctp_skb_pull(list, len);
1916 		skb->len -= (len-rlen);
1917 		skb->data_len -= (len-rlen);
1918 
1919 		if (!rlen)
1920 			return 0;
1921 
1922 		len = rlen;
1923 	}
1924 
1925 	return len;
1926 }
1927 
1928 /* API 3.1.3  recvmsg() - UDP Style Syntax
1929  *
1930  *  ssize_t recvmsg(int socket, struct msghdr *message,
1931  *                    int flags);
1932  *
1933  *  socket  - the socket descriptor of the endpoint.
1934  *  message - pointer to the msghdr structure which contains a single
1935  *            user message and possibly some ancillary data.
1936  *
1937  *            See Section 5 for complete description of the data
1938  *            structures.
1939  *
1940  *  flags   - flags sent or received with the user message, see Section
1941  *            5 for complete description of the flags.
1942  */
1943 static struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);
1944 
1945 SCTP_STATIC int sctp_recvmsg(struct kiocb *iocb, struct sock *sk,
1946 			     struct msghdr *msg, size_t len, int noblock,
1947 			     int flags, int *addr_len)
1948 {
1949 	struct sctp_ulpevent *event = NULL;
1950 	struct sctp_sock *sp = sctp_sk(sk);
1951 	struct sk_buff *skb;
1952 	int copied;
1953 	int err = 0;
1954 	int skb_len;
1955 
1956 	SCTP_DEBUG_PRINTK("sctp_recvmsg(%s: %p, %s: %p, %s: %zd, %s: %d, %s: "
1957 			  "0x%x, %s: %p)\n", "sk", sk, "msghdr", msg,
1958 			  "len", len, "knoblauch", noblock,
1959 			  "flags", flags, "addr_len", addr_len);
1960 
1961 	sctp_lock_sock(sk);
1962 
1963 	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED)) {
1964 		err = -ENOTCONN;
1965 		goto out;
1966 	}
1967 
1968 	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
1969 	if (!skb)
1970 		goto out;
1971 
1972 	/* Get the total length of the skb including any skb's in the
1973 	 * frag_list.
1974 	 */
1975 	skb_len = skb->len;
1976 
1977 	copied = skb_len;
1978 	if (copied > len)
1979 		copied = len;
1980 
1981 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1982 
1983 	event = sctp_skb2event(skb);
1984 
1985 	if (err)
1986 		goto out_free;
1987 
1988 	sock_recv_ts_and_drops(msg, sk, skb);
1989 	if (sctp_ulpevent_is_notification(event)) {
1990 		msg->msg_flags |= MSG_NOTIFICATION;
1991 		sp->pf->event_msgname(event, msg->msg_name, addr_len);
1992 	} else {
1993 		sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
1994 	}
1995 
1996 	/* Check if we allow SCTP_SNDRCVINFO. */
1997 	if (sp->subscribe.sctp_data_io_event)
1998 		sctp_ulpevent_read_sndrcvinfo(event, msg);
1999 #if 0
2000 	/* FIXME: we should be calling IP/IPv6 layers.  */
2001 	if (sk->sk_protinfo.af_inet.cmsg_flags)
2002 		ip_cmsg_recv(msg, skb);
2003 #endif
2004 
2005 	err = copied;
2006 
2007 	/* If skb's length exceeds the user's buffer, update the skb and
2008 	 * push it back to the receive_queue so that the next call to
2009 	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
2010 	 */
2011 	if (skb_len > copied) {
2012 		msg->msg_flags &= ~MSG_EOR;
2013 		if (flags & MSG_PEEK)
2014 			goto out_free;
2015 		sctp_skb_pull(skb, copied);
2016 		skb_queue_head(&sk->sk_receive_queue, skb);
2017 
2018 		/* When only partial message is copied to the user, increase
2019 		 * rwnd by that amount. If all the data in the skb is read,
2020 		 * rwnd is updated when the event is freed.
2021 		 */
2022 		if (!sctp_ulpevent_is_notification(event))
2023 			sctp_assoc_rwnd_increase(event->asoc, copied);
2024 		goto out;
2025 	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
2026 		   (event->msg_flags & MSG_EOR))
2027 		msg->msg_flags |= MSG_EOR;
2028 	else
2029 		msg->msg_flags &= ~MSG_EOR;
2030 
2031 out_free:
2032 	if (flags & MSG_PEEK) {
2033 		/* Release the skb reference acquired after peeking the skb in
2034 		 * sctp_skb_recv_datagram().
2035 		 */
2036 		kfree_skb(skb);
2037 	} else {
2038 		/* Free the event which includes releasing the reference to
2039 		 * the owner of the skb, freeing the skb and updating the
2040 		 * rwnd.
2041 		 */
2042 		sctp_ulpevent_free(event);
2043 	}
2044 out:
2045 	sctp_release_sock(sk);
2046 	return err;
2047 }
2048 
2049 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
2050  *
2051  * This option is a on/off flag.  If enabled no SCTP message
2052  * fragmentation will be performed.  Instead if a message being sent
2053  * exceeds the current PMTU size, the message will NOT be sent and
2054  * instead a error will be indicated to the user.
2055  */
2056 static int sctp_setsockopt_disable_fragments(struct sock *sk,
2057 					     char __user *optval,
2058 					     unsigned int optlen)
2059 {
2060 	int val;
2061 
2062 	if (optlen < sizeof(int))
2063 		return -EINVAL;
2064 
2065 	if (get_user(val, (int __user *)optval))
2066 		return -EFAULT;
2067 
2068 	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
2069 
2070 	return 0;
2071 }
2072 
2073 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
2074 				  unsigned int optlen)
2075 {
2076 	if (optlen > sizeof(struct sctp_event_subscribe))
2077 		return -EINVAL;
2078 	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
2079 		return -EFAULT;
2080 	return 0;
2081 }
2082 
2083 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
2084  *
2085  * This socket option is applicable to the UDP-style socket only.  When
2086  * set it will cause associations that are idle for more than the
2087  * specified number of seconds to automatically close.  An association
2088  * being idle is defined an association that has NOT sent or received
2089  * user data.  The special value of '0' indicates that no automatic
2090  * close of any associations should be performed.  The option expects an
2091  * integer defining the number of seconds of idle time before an
2092  * association is closed.
2093  */
2094 static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
2095 				     unsigned int optlen)
2096 {
2097 	struct sctp_sock *sp = sctp_sk(sk);
2098 
2099 	/* Applicable to UDP-style socket only */
2100 	if (sctp_style(sk, TCP))
2101 		return -EOPNOTSUPP;
2102 	if (optlen != sizeof(int))
2103 		return -EINVAL;
2104 	if (copy_from_user(&sp->autoclose, optval, optlen))
2105 		return -EFAULT;
2106 	/* make sure it won't exceed MAX_SCHEDULE_TIMEOUT */
2107 	sp->autoclose = min_t(long, sp->autoclose, MAX_SCHEDULE_TIMEOUT / HZ);
2108 
2109 	return 0;
2110 }
2111 
2112 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
2113  *
2114  * Applications can enable or disable heartbeats for any peer address of
2115  * an association, modify an address's heartbeat interval, force a
2116  * heartbeat to be sent immediately, and adjust the address's maximum
2117  * number of retransmissions sent before an address is considered
2118  * unreachable.  The following structure is used to access and modify an
2119  * address's parameters:
2120  *
2121  *  struct sctp_paddrparams {
2122  *     sctp_assoc_t            spp_assoc_id;
2123  *     struct sockaddr_storage spp_address;
2124  *     uint32_t                spp_hbinterval;
2125  *     uint16_t                spp_pathmaxrxt;
2126  *     uint32_t                spp_pathmtu;
2127  *     uint32_t                spp_sackdelay;
2128  *     uint32_t                spp_flags;
2129  * };
2130  *
2131  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
2132  *                     application, and identifies the association for
2133  *                     this query.
2134  *   spp_address     - This specifies which address is of interest.
2135  *   spp_hbinterval  - This contains the value of the heartbeat interval,
2136  *                     in milliseconds.  If a  value of zero
2137  *                     is present in this field then no changes are to
2138  *                     be made to this parameter.
2139  *   spp_pathmaxrxt  - This contains the maximum number of
2140  *                     retransmissions before this address shall be
2141  *                     considered unreachable. If a  value of zero
2142  *                     is present in this field then no changes are to
2143  *                     be made to this parameter.
2144  *   spp_pathmtu     - When Path MTU discovery is disabled the value
2145  *                     specified here will be the "fixed" path mtu.
2146  *                     Note that if the spp_address field is empty
2147  *                     then all associations on this address will
2148  *                     have this fixed path mtu set upon them.
2149  *
2150  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
2151  *                     the number of milliseconds that sacks will be delayed
2152  *                     for. This value will apply to all addresses of an
2153  *                     association if the spp_address field is empty. Note
2154  *                     also, that if delayed sack is enabled and this
2155  *                     value is set to 0, no change is made to the last
2156  *                     recorded delayed sack timer value.
2157  *
2158  *   spp_flags       - These flags are used to control various features
2159  *                     on an association. The flag field may contain
2160  *                     zero or more of the following options.
2161  *
2162  *                     SPP_HB_ENABLE  - Enable heartbeats on the
2163  *                     specified address. Note that if the address
2164  *                     field is empty all addresses for the association
2165  *                     have heartbeats enabled upon them.
2166  *
2167  *                     SPP_HB_DISABLE - Disable heartbeats on the
2168  *                     speicifed address. Note that if the address
2169  *                     field is empty all addresses for the association
2170  *                     will have their heartbeats disabled. Note also
2171  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
2172  *                     mutually exclusive, only one of these two should
2173  *                     be specified. Enabling both fields will have
2174  *                     undetermined results.
2175  *
2176  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
2177  *                     to be made immediately.
2178  *
2179  *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
2180  *                     heartbeat delayis to be set to the value of 0
2181  *                     milliseconds.
2182  *
2183  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
2184  *                     discovery upon the specified address. Note that
2185  *                     if the address feild is empty then all addresses
2186  *                     on the association are effected.
2187  *
2188  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
2189  *                     discovery upon the specified address. Note that
2190  *                     if the address feild is empty then all addresses
2191  *                     on the association are effected. Not also that
2192  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
2193  *                     exclusive. Enabling both will have undetermined
2194  *                     results.
2195  *
2196  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
2197  *                     on delayed sack. The time specified in spp_sackdelay
2198  *                     is used to specify the sack delay for this address. Note
2199  *                     that if spp_address is empty then all addresses will
2200  *                     enable delayed sack and take on the sack delay
2201  *                     value specified in spp_sackdelay.
2202  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
2203  *                     off delayed sack. If the spp_address field is blank then
2204  *                     delayed sack is disabled for the entire association. Note
2205  *                     also that this field is mutually exclusive to
2206  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
2207  *                     results.
2208  */
2209 static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
2210 				       struct sctp_transport   *trans,
2211 				       struct sctp_association *asoc,
2212 				       struct sctp_sock        *sp,
2213 				       int                      hb_change,
2214 				       int                      pmtud_change,
2215 				       int                      sackdelay_change)
2216 {
2217 	int error;
2218 
2219 	if (params->spp_flags & SPP_HB_DEMAND && trans) {
2220 		error = sctp_primitive_REQUESTHEARTBEAT (trans->asoc, trans);
2221 		if (error)
2222 			return error;
2223 	}
2224 
2225 	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
2226 	 * this field is ignored.  Note also that a value of zero indicates
2227 	 * the current setting should be left unchanged.
2228 	 */
2229 	if (params->spp_flags & SPP_HB_ENABLE) {
2230 
2231 		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
2232 		 * set.  This lets us use 0 value when this flag
2233 		 * is set.
2234 		 */
2235 		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
2236 			params->spp_hbinterval = 0;
2237 
2238 		if (params->spp_hbinterval ||
2239 		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
2240 			if (trans) {
2241 				trans->hbinterval =
2242 				    msecs_to_jiffies(params->spp_hbinterval);
2243 			} else if (asoc) {
2244 				asoc->hbinterval =
2245 				    msecs_to_jiffies(params->spp_hbinterval);
2246 			} else {
2247 				sp->hbinterval = params->spp_hbinterval;
2248 			}
2249 		}
2250 	}
2251 
2252 	if (hb_change) {
2253 		if (trans) {
2254 			trans->param_flags =
2255 				(trans->param_flags & ~SPP_HB) | hb_change;
2256 		} else if (asoc) {
2257 			asoc->param_flags =
2258 				(asoc->param_flags & ~SPP_HB) | hb_change;
2259 		} else {
2260 			sp->param_flags =
2261 				(sp->param_flags & ~SPP_HB) | hb_change;
2262 		}
2263 	}
2264 
2265 	/* When Path MTU discovery is disabled the value specified here will
2266 	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
2267 	 * include the flag SPP_PMTUD_DISABLE for this field to have any
2268 	 * effect).
2269 	 */
2270 	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
2271 		if (trans) {
2272 			trans->pathmtu = params->spp_pathmtu;
2273 			sctp_assoc_sync_pmtu(asoc);
2274 		} else if (asoc) {
2275 			asoc->pathmtu = params->spp_pathmtu;
2276 			sctp_frag_point(asoc, params->spp_pathmtu);
2277 		} else {
2278 			sp->pathmtu = params->spp_pathmtu;
2279 		}
2280 	}
2281 
2282 	if (pmtud_change) {
2283 		if (trans) {
2284 			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
2285 				(params->spp_flags & SPP_PMTUD_ENABLE);
2286 			trans->param_flags =
2287 				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
2288 			if (update) {
2289 				sctp_transport_pmtu(trans, sctp_opt2sk(sp));
2290 				sctp_assoc_sync_pmtu(asoc);
2291 			}
2292 		} else if (asoc) {
2293 			asoc->param_flags =
2294 				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
2295 		} else {
2296 			sp->param_flags =
2297 				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
2298 		}
2299 	}
2300 
2301 	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
2302 	 * value of this field is ignored.  Note also that a value of zero
2303 	 * indicates the current setting should be left unchanged.
2304 	 */
2305 	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
2306 		if (trans) {
2307 			trans->sackdelay =
2308 				msecs_to_jiffies(params->spp_sackdelay);
2309 		} else if (asoc) {
2310 			asoc->sackdelay =
2311 				msecs_to_jiffies(params->spp_sackdelay);
2312 		} else {
2313 			sp->sackdelay = params->spp_sackdelay;
2314 		}
2315 	}
2316 
2317 	if (sackdelay_change) {
2318 		if (trans) {
2319 			trans->param_flags =
2320 				(trans->param_flags & ~SPP_SACKDELAY) |
2321 				sackdelay_change;
2322 		} else if (asoc) {
2323 			asoc->param_flags =
2324 				(asoc->param_flags & ~SPP_SACKDELAY) |
2325 				sackdelay_change;
2326 		} else {
2327 			sp->param_flags =
2328 				(sp->param_flags & ~SPP_SACKDELAY) |
2329 				sackdelay_change;
2330 		}
2331 	}
2332 
2333 	/* Note that a value of zero indicates the current setting should be
2334 	   left unchanged.
2335 	 */
2336 	if (params->spp_pathmaxrxt) {
2337 		if (trans) {
2338 			trans->pathmaxrxt = params->spp_pathmaxrxt;
2339 		} else if (asoc) {
2340 			asoc->pathmaxrxt = params->spp_pathmaxrxt;
2341 		} else {
2342 			sp->pathmaxrxt = params->spp_pathmaxrxt;
2343 		}
2344 	}
2345 
2346 	return 0;
2347 }
2348 
2349 static int sctp_setsockopt_peer_addr_params(struct sock *sk,
2350 					    char __user *optval,
2351 					    unsigned int optlen)
2352 {
2353 	struct sctp_paddrparams  params;
2354 	struct sctp_transport   *trans = NULL;
2355 	struct sctp_association *asoc = NULL;
2356 	struct sctp_sock        *sp = sctp_sk(sk);
2357 	int error;
2358 	int hb_change, pmtud_change, sackdelay_change;
2359 
2360 	if (optlen != sizeof(struct sctp_paddrparams))
2361 		return - EINVAL;
2362 
2363 	if (copy_from_user(&params, optval, optlen))
2364 		return -EFAULT;
2365 
2366 	/* Validate flags and value parameters. */
2367 	hb_change        = params.spp_flags & SPP_HB;
2368 	pmtud_change     = params.spp_flags & SPP_PMTUD;
2369 	sackdelay_change = params.spp_flags & SPP_SACKDELAY;
2370 
2371 	if (hb_change        == SPP_HB ||
2372 	    pmtud_change     == SPP_PMTUD ||
2373 	    sackdelay_change == SPP_SACKDELAY ||
2374 	    params.spp_sackdelay > 500 ||
2375 	    (params.spp_pathmtu &&
2376 	     params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
2377 		return -EINVAL;
2378 
2379 	/* If an address other than INADDR_ANY is specified, and
2380 	 * no transport is found, then the request is invalid.
2381 	 */
2382 	if (!sctp_is_any(sk, ( union sctp_addr *)&params.spp_address)) {
2383 		trans = sctp_addr_id2transport(sk, &params.spp_address,
2384 					       params.spp_assoc_id);
2385 		if (!trans)
2386 			return -EINVAL;
2387 	}
2388 
2389 	/* Get association, if assoc_id != 0 and the socket is a one
2390 	 * to many style socket, and an association was not found, then
2391 	 * the id was invalid.
2392 	 */
2393 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
2394 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
2395 		return -EINVAL;
2396 
2397 	/* Heartbeat demand can only be sent on a transport or
2398 	 * association, but not a socket.
2399 	 */
2400 	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
2401 		return -EINVAL;
2402 
2403 	/* Process parameters. */
2404 	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2405 					    hb_change, pmtud_change,
2406 					    sackdelay_change);
2407 
2408 	if (error)
2409 		return error;
2410 
2411 	/* If changes are for association, also apply parameters to each
2412 	 * transport.
2413 	 */
2414 	if (!trans && asoc) {
2415 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2416 				transports) {
2417 			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2418 						    hb_change, pmtud_change,
2419 						    sackdelay_change);
2420 		}
2421 	}
2422 
2423 	return 0;
2424 }
2425 
2426 /*
2427  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
2428  *
2429  * This option will effect the way delayed acks are performed.  This
2430  * option allows you to get or set the delayed ack time, in
2431  * milliseconds.  It also allows changing the delayed ack frequency.
2432  * Changing the frequency to 1 disables the delayed sack algorithm.  If
2433  * the assoc_id is 0, then this sets or gets the endpoints default
2434  * values.  If the assoc_id field is non-zero, then the set or get
2435  * effects the specified association for the one to many model (the
2436  * assoc_id field is ignored by the one to one model).  Note that if
2437  * sack_delay or sack_freq are 0 when setting this option, then the
2438  * current values will remain unchanged.
2439  *
2440  * struct sctp_sack_info {
2441  *     sctp_assoc_t            sack_assoc_id;
2442  *     uint32_t                sack_delay;
2443  *     uint32_t                sack_freq;
2444  * };
2445  *
2446  * sack_assoc_id -  This parameter, indicates which association the user
2447  *    is performing an action upon.  Note that if this field's value is
2448  *    zero then the endpoints default value is changed (effecting future
2449  *    associations only).
2450  *
2451  * sack_delay -  This parameter contains the number of milliseconds that
2452  *    the user is requesting the delayed ACK timer be set to.  Note that
2453  *    this value is defined in the standard to be between 200 and 500
2454  *    milliseconds.
2455  *
2456  * sack_freq -  This parameter contains the number of packets that must
2457  *    be received before a sack is sent without waiting for the delay
2458  *    timer to expire.  The default value for this is 2, setting this
2459  *    value to 1 will disable the delayed sack algorithm.
2460  */
2461 
2462 static int sctp_setsockopt_delayed_ack(struct sock *sk,
2463 				       char __user *optval, unsigned int optlen)
2464 {
2465 	struct sctp_sack_info    params;
2466 	struct sctp_transport   *trans = NULL;
2467 	struct sctp_association *asoc = NULL;
2468 	struct sctp_sock        *sp = sctp_sk(sk);
2469 
2470 	if (optlen == sizeof(struct sctp_sack_info)) {
2471 		if (copy_from_user(&params, optval, optlen))
2472 			return -EFAULT;
2473 
2474 		if (params.sack_delay == 0 && params.sack_freq == 0)
2475 			return 0;
2476 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
2477 		pr_warn("Use of struct sctp_assoc_value in delayed_ack socket option deprecated\n");
2478 		pr_warn("Use struct sctp_sack_info instead\n");
2479 		if (copy_from_user(&params, optval, optlen))
2480 			return -EFAULT;
2481 
2482 		if (params.sack_delay == 0)
2483 			params.sack_freq = 1;
2484 		else
2485 			params.sack_freq = 0;
2486 	} else
2487 		return - EINVAL;
2488 
2489 	/* Validate value parameter. */
2490 	if (params.sack_delay > 500)
2491 		return -EINVAL;
2492 
2493 	/* Get association, if sack_assoc_id != 0 and the socket is a one
2494 	 * to many style socket, and an association was not found, then
2495 	 * the id was invalid.
2496 	 */
2497 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
2498 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
2499 		return -EINVAL;
2500 
2501 	if (params.sack_delay) {
2502 		if (asoc) {
2503 			asoc->sackdelay =
2504 				msecs_to_jiffies(params.sack_delay);
2505 			asoc->param_flags =
2506 				(asoc->param_flags & ~SPP_SACKDELAY) |
2507 				SPP_SACKDELAY_ENABLE;
2508 		} else {
2509 			sp->sackdelay = params.sack_delay;
2510 			sp->param_flags =
2511 				(sp->param_flags & ~SPP_SACKDELAY) |
2512 				SPP_SACKDELAY_ENABLE;
2513 		}
2514 	}
2515 
2516 	if (params.sack_freq == 1) {
2517 		if (asoc) {
2518 			asoc->param_flags =
2519 				(asoc->param_flags & ~SPP_SACKDELAY) |
2520 				SPP_SACKDELAY_DISABLE;
2521 		} else {
2522 			sp->param_flags =
2523 				(sp->param_flags & ~SPP_SACKDELAY) |
2524 				SPP_SACKDELAY_DISABLE;
2525 		}
2526 	} else if (params.sack_freq > 1) {
2527 		if (asoc) {
2528 			asoc->sackfreq = params.sack_freq;
2529 			asoc->param_flags =
2530 				(asoc->param_flags & ~SPP_SACKDELAY) |
2531 				SPP_SACKDELAY_ENABLE;
2532 		} else {
2533 			sp->sackfreq = params.sack_freq;
2534 			sp->param_flags =
2535 				(sp->param_flags & ~SPP_SACKDELAY) |
2536 				SPP_SACKDELAY_ENABLE;
2537 		}
2538 	}
2539 
2540 	/* If change is for association, also apply to each transport. */
2541 	if (asoc) {
2542 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2543 				transports) {
2544 			if (params.sack_delay) {
2545 				trans->sackdelay =
2546 					msecs_to_jiffies(params.sack_delay);
2547 				trans->param_flags =
2548 					(trans->param_flags & ~SPP_SACKDELAY) |
2549 					SPP_SACKDELAY_ENABLE;
2550 			}
2551 			if (params.sack_freq == 1) {
2552 				trans->param_flags =
2553 					(trans->param_flags & ~SPP_SACKDELAY) |
2554 					SPP_SACKDELAY_DISABLE;
2555 			} else if (params.sack_freq > 1) {
2556 				trans->sackfreq = params.sack_freq;
2557 				trans->param_flags =
2558 					(trans->param_flags & ~SPP_SACKDELAY) |
2559 					SPP_SACKDELAY_ENABLE;
2560 			}
2561 		}
2562 	}
2563 
2564 	return 0;
2565 }
2566 
2567 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
2568  *
2569  * Applications can specify protocol parameters for the default association
2570  * initialization.  The option name argument to setsockopt() and getsockopt()
2571  * is SCTP_INITMSG.
2572  *
2573  * Setting initialization parameters is effective only on an unconnected
2574  * socket (for UDP-style sockets only future associations are effected
2575  * by the change).  With TCP-style sockets, this option is inherited by
2576  * sockets derived from a listener socket.
2577  */
2578 static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, unsigned int optlen)
2579 {
2580 	struct sctp_initmsg sinit;
2581 	struct sctp_sock *sp = sctp_sk(sk);
2582 
2583 	if (optlen != sizeof(struct sctp_initmsg))
2584 		return -EINVAL;
2585 	if (copy_from_user(&sinit, optval, optlen))
2586 		return -EFAULT;
2587 
2588 	if (sinit.sinit_num_ostreams)
2589 		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
2590 	if (sinit.sinit_max_instreams)
2591 		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
2592 	if (sinit.sinit_max_attempts)
2593 		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
2594 	if (sinit.sinit_max_init_timeo)
2595 		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
2596 
2597 	return 0;
2598 }
2599 
2600 /*
2601  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
2602  *
2603  *   Applications that wish to use the sendto() system call may wish to
2604  *   specify a default set of parameters that would normally be supplied
2605  *   through the inclusion of ancillary data.  This socket option allows
2606  *   such an application to set the default sctp_sndrcvinfo structure.
2607  *   The application that wishes to use this socket option simply passes
2608  *   in to this call the sctp_sndrcvinfo structure defined in Section
2609  *   5.2.2) The input parameters accepted by this call include
2610  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
2611  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
2612  *   to this call if the caller is using the UDP model.
2613  */
2614 static int sctp_setsockopt_default_send_param(struct sock *sk,
2615 					      char __user *optval,
2616 					      unsigned int optlen)
2617 {
2618 	struct sctp_sndrcvinfo info;
2619 	struct sctp_association *asoc;
2620 	struct sctp_sock *sp = sctp_sk(sk);
2621 
2622 	if (optlen != sizeof(struct sctp_sndrcvinfo))
2623 		return -EINVAL;
2624 	if (copy_from_user(&info, optval, optlen))
2625 		return -EFAULT;
2626 
2627 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
2628 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
2629 		return -EINVAL;
2630 
2631 	if (asoc) {
2632 		asoc->default_stream = info.sinfo_stream;
2633 		asoc->default_flags = info.sinfo_flags;
2634 		asoc->default_ppid = info.sinfo_ppid;
2635 		asoc->default_context = info.sinfo_context;
2636 		asoc->default_timetolive = info.sinfo_timetolive;
2637 	} else {
2638 		sp->default_stream = info.sinfo_stream;
2639 		sp->default_flags = info.sinfo_flags;
2640 		sp->default_ppid = info.sinfo_ppid;
2641 		sp->default_context = info.sinfo_context;
2642 		sp->default_timetolive = info.sinfo_timetolive;
2643 	}
2644 
2645 	return 0;
2646 }
2647 
2648 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
2649  *
2650  * Requests that the local SCTP stack use the enclosed peer address as
2651  * the association primary.  The enclosed address must be one of the
2652  * association peer's addresses.
2653  */
2654 static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
2655 					unsigned int optlen)
2656 {
2657 	struct sctp_prim prim;
2658 	struct sctp_transport *trans;
2659 
2660 	if (optlen != sizeof(struct sctp_prim))
2661 		return -EINVAL;
2662 
2663 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
2664 		return -EFAULT;
2665 
2666 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
2667 	if (!trans)
2668 		return -EINVAL;
2669 
2670 	sctp_assoc_set_primary(trans->asoc, trans);
2671 
2672 	return 0;
2673 }
2674 
2675 /*
2676  * 7.1.5 SCTP_NODELAY
2677  *
2678  * Turn on/off any Nagle-like algorithm.  This means that packets are
2679  * generally sent as soon as possible and no unnecessary delays are
2680  * introduced, at the cost of more packets in the network.  Expects an
2681  *  integer boolean flag.
2682  */
2683 static int sctp_setsockopt_nodelay(struct sock *sk, char __user *optval,
2684 				   unsigned int optlen)
2685 {
2686 	int val;
2687 
2688 	if (optlen < sizeof(int))
2689 		return -EINVAL;
2690 	if (get_user(val, (int __user *)optval))
2691 		return -EFAULT;
2692 
2693 	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
2694 	return 0;
2695 }
2696 
2697 /*
2698  *
2699  * 7.1.1 SCTP_RTOINFO
2700  *
2701  * The protocol parameters used to initialize and bound retransmission
2702  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
2703  * and modify these parameters.
2704  * All parameters are time values, in milliseconds.  A value of 0, when
2705  * modifying the parameters, indicates that the current value should not
2706  * be changed.
2707  *
2708  */
2709 static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, unsigned int optlen)
2710 {
2711 	struct sctp_rtoinfo rtoinfo;
2712 	struct sctp_association *asoc;
2713 
2714 	if (optlen != sizeof (struct sctp_rtoinfo))
2715 		return -EINVAL;
2716 
2717 	if (copy_from_user(&rtoinfo, optval, optlen))
2718 		return -EFAULT;
2719 
2720 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
2721 
2722 	/* Set the values to the specific association */
2723 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
2724 		return -EINVAL;
2725 
2726 	if (asoc) {
2727 		if (rtoinfo.srto_initial != 0)
2728 			asoc->rto_initial =
2729 				msecs_to_jiffies(rtoinfo.srto_initial);
2730 		if (rtoinfo.srto_max != 0)
2731 			asoc->rto_max = msecs_to_jiffies(rtoinfo.srto_max);
2732 		if (rtoinfo.srto_min != 0)
2733 			asoc->rto_min = msecs_to_jiffies(rtoinfo.srto_min);
2734 	} else {
2735 		/* If there is no association or the association-id = 0
2736 		 * set the values to the endpoint.
2737 		 */
2738 		struct sctp_sock *sp = sctp_sk(sk);
2739 
2740 		if (rtoinfo.srto_initial != 0)
2741 			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
2742 		if (rtoinfo.srto_max != 0)
2743 			sp->rtoinfo.srto_max = rtoinfo.srto_max;
2744 		if (rtoinfo.srto_min != 0)
2745 			sp->rtoinfo.srto_min = rtoinfo.srto_min;
2746 	}
2747 
2748 	return 0;
2749 }
2750 
2751 /*
2752  *
2753  * 7.1.2 SCTP_ASSOCINFO
2754  *
2755  * This option is used to tune the maximum retransmission attempts
2756  * of the association.
2757  * Returns an error if the new association retransmission value is
2758  * greater than the sum of the retransmission value  of the peer.
2759  * See [SCTP] for more information.
2760  *
2761  */
2762 static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, unsigned int optlen)
2763 {
2764 
2765 	struct sctp_assocparams assocparams;
2766 	struct sctp_association *asoc;
2767 
2768 	if (optlen != sizeof(struct sctp_assocparams))
2769 		return -EINVAL;
2770 	if (copy_from_user(&assocparams, optval, optlen))
2771 		return -EFAULT;
2772 
2773 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
2774 
2775 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
2776 		return -EINVAL;
2777 
2778 	/* Set the values to the specific association */
2779 	if (asoc) {
2780 		if (assocparams.sasoc_asocmaxrxt != 0) {
2781 			__u32 path_sum = 0;
2782 			int   paths = 0;
2783 			struct sctp_transport *peer_addr;
2784 
2785 			list_for_each_entry(peer_addr, &asoc->peer.transport_addr_list,
2786 					transports) {
2787 				path_sum += peer_addr->pathmaxrxt;
2788 				paths++;
2789 			}
2790 
2791 			/* Only validate asocmaxrxt if we have more than
2792 			 * one path/transport.  We do this because path
2793 			 * retransmissions are only counted when we have more
2794 			 * then one path.
2795 			 */
2796 			if (paths > 1 &&
2797 			    assocparams.sasoc_asocmaxrxt > path_sum)
2798 				return -EINVAL;
2799 
2800 			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
2801 		}
2802 
2803 		if (assocparams.sasoc_cookie_life != 0) {
2804 			asoc->cookie_life.tv_sec =
2805 					assocparams.sasoc_cookie_life / 1000;
2806 			asoc->cookie_life.tv_usec =
2807 					(assocparams.sasoc_cookie_life % 1000)
2808 					* 1000;
2809 		}
2810 	} else {
2811 		/* Set the values to the endpoint */
2812 		struct sctp_sock *sp = sctp_sk(sk);
2813 
2814 		if (assocparams.sasoc_asocmaxrxt != 0)
2815 			sp->assocparams.sasoc_asocmaxrxt =
2816 						assocparams.sasoc_asocmaxrxt;
2817 		if (assocparams.sasoc_cookie_life != 0)
2818 			sp->assocparams.sasoc_cookie_life =
2819 						assocparams.sasoc_cookie_life;
2820 	}
2821 	return 0;
2822 }
2823 
2824 /*
2825  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
2826  *
2827  * This socket option is a boolean flag which turns on or off mapped V4
2828  * addresses.  If this option is turned on and the socket is type
2829  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
2830  * If this option is turned off, then no mapping will be done of V4
2831  * addresses and a user will receive both PF_INET6 and PF_INET type
2832  * addresses on the socket.
2833  */
2834 static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsigned int optlen)
2835 {
2836 	int val;
2837 	struct sctp_sock *sp = sctp_sk(sk);
2838 
2839 	if (optlen < sizeof(int))
2840 		return -EINVAL;
2841 	if (get_user(val, (int __user *)optval))
2842 		return -EFAULT;
2843 	if (val)
2844 		sp->v4mapped = 1;
2845 	else
2846 		sp->v4mapped = 0;
2847 
2848 	return 0;
2849 }
2850 
2851 /*
2852  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
2853  * This option will get or set the maximum size to put in any outgoing
2854  * SCTP DATA chunk.  If a message is larger than this size it will be
2855  * fragmented by SCTP into the specified size.  Note that the underlying
2856  * SCTP implementation may fragment into smaller sized chunks when the
2857  * PMTU of the underlying association is smaller than the value set by
2858  * the user.  The default value for this option is '0' which indicates
2859  * the user is NOT limiting fragmentation and only the PMTU will effect
2860  * SCTP's choice of DATA chunk size.  Note also that values set larger
2861  * than the maximum size of an IP datagram will effectively let SCTP
2862  * control fragmentation (i.e. the same as setting this option to 0).
2863  *
2864  * The following structure is used to access and modify this parameter:
2865  *
2866  * struct sctp_assoc_value {
2867  *   sctp_assoc_t assoc_id;
2868  *   uint32_t assoc_value;
2869  * };
2870  *
2871  * assoc_id:  This parameter is ignored for one-to-one style sockets.
2872  *    For one-to-many style sockets this parameter indicates which
2873  *    association the user is performing an action upon.  Note that if
2874  *    this field's value is zero then the endpoints default value is
2875  *    changed (effecting future associations only).
2876  * assoc_value:  This parameter specifies the maximum size in bytes.
2877  */
2878 static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
2879 {
2880 	struct sctp_assoc_value params;
2881 	struct sctp_association *asoc;
2882 	struct sctp_sock *sp = sctp_sk(sk);
2883 	int val;
2884 
2885 	if (optlen == sizeof(int)) {
2886 		pr_warn("Use of int in maxseg socket option deprecated\n");
2887 		pr_warn("Use struct sctp_assoc_value instead\n");
2888 		if (copy_from_user(&val, optval, optlen))
2889 			return -EFAULT;
2890 		params.assoc_id = 0;
2891 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
2892 		if (copy_from_user(&params, optval, optlen))
2893 			return -EFAULT;
2894 		val = params.assoc_value;
2895 	} else
2896 		return -EINVAL;
2897 
2898 	if ((val != 0) && ((val < 8) || (val > SCTP_MAX_CHUNK_LEN)))
2899 		return -EINVAL;
2900 
2901 	asoc = sctp_id2assoc(sk, params.assoc_id);
2902 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
2903 		return -EINVAL;
2904 
2905 	if (asoc) {
2906 		if (val == 0) {
2907 			val = asoc->pathmtu;
2908 			val -= sp->pf->af->net_header_len;
2909 			val -= sizeof(struct sctphdr) +
2910 					sizeof(struct sctp_data_chunk);
2911 		}
2912 		asoc->user_frag = val;
2913 		asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
2914 	} else {
2915 		sp->user_frag = val;
2916 	}
2917 
2918 	return 0;
2919 }
2920 
2921 
2922 /*
2923  *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
2924  *
2925  *   Requests that the peer mark the enclosed address as the association
2926  *   primary. The enclosed address must be one of the association's
2927  *   locally bound addresses. The following structure is used to make a
2928  *   set primary request:
2929  */
2930 static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
2931 					     unsigned int optlen)
2932 {
2933 	struct sctp_sock	*sp;
2934 	struct sctp_association	*asoc = NULL;
2935 	struct sctp_setpeerprim	prim;
2936 	struct sctp_chunk	*chunk;
2937 	struct sctp_af		*af;
2938 	int 			err;
2939 
2940 	sp = sctp_sk(sk);
2941 
2942 	if (!sctp_addip_enable)
2943 		return -EPERM;
2944 
2945 	if (optlen != sizeof(struct sctp_setpeerprim))
2946 		return -EINVAL;
2947 
2948 	if (copy_from_user(&prim, optval, optlen))
2949 		return -EFAULT;
2950 
2951 	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
2952 	if (!asoc)
2953 		return -EINVAL;
2954 
2955 	if (!asoc->peer.asconf_capable)
2956 		return -EPERM;
2957 
2958 	if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
2959 		return -EPERM;
2960 
2961 	if (!sctp_state(asoc, ESTABLISHED))
2962 		return -ENOTCONN;
2963 
2964 	af = sctp_get_af_specific(prim.sspp_addr.ss_family);
2965 	if (!af)
2966 		return -EINVAL;
2967 
2968 	if (!af->addr_valid((union sctp_addr *)&prim.sspp_addr, sp, NULL))
2969 		return -EADDRNOTAVAIL;
2970 
2971 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
2972 		return -EADDRNOTAVAIL;
2973 
2974 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
2975 	chunk = sctp_make_asconf_set_prim(asoc,
2976 					  (union sctp_addr *)&prim.sspp_addr);
2977 	if (!chunk)
2978 		return -ENOMEM;
2979 
2980 	err = sctp_send_asconf(asoc, chunk);
2981 
2982 	SCTP_DEBUG_PRINTK("We set peer primary addr primitively.\n");
2983 
2984 	return err;
2985 }
2986 
2987 static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
2988 					    unsigned int optlen)
2989 {
2990 	struct sctp_setadaptation adaptation;
2991 
2992 	if (optlen != sizeof(struct sctp_setadaptation))
2993 		return -EINVAL;
2994 	if (copy_from_user(&adaptation, optval, optlen))
2995 		return -EFAULT;
2996 
2997 	sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
2998 
2999 	return 0;
3000 }
3001 
3002 /*
3003  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
3004  *
3005  * The context field in the sctp_sndrcvinfo structure is normally only
3006  * used when a failed message is retrieved holding the value that was
3007  * sent down on the actual send call.  This option allows the setting of
3008  * a default context on an association basis that will be received on
3009  * reading messages from the peer.  This is especially helpful in the
3010  * one-2-many model for an application to keep some reference to an
3011  * internal state machine that is processing messages on the
3012  * association.  Note that the setting of this value only effects
3013  * received messages from the peer and does not effect the value that is
3014  * saved with outbound messages.
3015  */
3016 static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
3017 				   unsigned int optlen)
3018 {
3019 	struct sctp_assoc_value params;
3020 	struct sctp_sock *sp;
3021 	struct sctp_association *asoc;
3022 
3023 	if (optlen != sizeof(struct sctp_assoc_value))
3024 		return -EINVAL;
3025 	if (copy_from_user(&params, optval, optlen))
3026 		return -EFAULT;
3027 
3028 	sp = sctp_sk(sk);
3029 
3030 	if (params.assoc_id != 0) {
3031 		asoc = sctp_id2assoc(sk, params.assoc_id);
3032 		if (!asoc)
3033 			return -EINVAL;
3034 		asoc->default_rcv_context = params.assoc_value;
3035 	} else {
3036 		sp->default_rcv_context = params.assoc_value;
3037 	}
3038 
3039 	return 0;
3040 }
3041 
3042 /*
3043  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
3044  *
3045  * This options will at a minimum specify if the implementation is doing
3046  * fragmented interleave.  Fragmented interleave, for a one to many
3047  * socket, is when subsequent calls to receive a message may return
3048  * parts of messages from different associations.  Some implementations
3049  * may allow you to turn this value on or off.  If so, when turned off,
3050  * no fragment interleave will occur (which will cause a head of line
3051  * blocking amongst multiple associations sharing the same one to many
3052  * socket).  When this option is turned on, then each receive call may
3053  * come from a different association (thus the user must receive data
3054  * with the extended calls (e.g. sctp_recvmsg) to keep track of which
3055  * association each receive belongs to.
3056  *
3057  * This option takes a boolean value.  A non-zero value indicates that
3058  * fragmented interleave is on.  A value of zero indicates that
3059  * fragmented interleave is off.
3060  *
3061  * Note that it is important that an implementation that allows this
3062  * option to be turned on, have it off by default.  Otherwise an unaware
3063  * application using the one to many model may become confused and act
3064  * incorrectly.
3065  */
3066 static int sctp_setsockopt_fragment_interleave(struct sock *sk,
3067 					       char __user *optval,
3068 					       unsigned int optlen)
3069 {
3070 	int val;
3071 
3072 	if (optlen != sizeof(int))
3073 		return -EINVAL;
3074 	if (get_user(val, (int __user *)optval))
3075 		return -EFAULT;
3076 
3077 	sctp_sk(sk)->frag_interleave = (val == 0) ? 0 : 1;
3078 
3079 	return 0;
3080 }
3081 
3082 /*
3083  * 8.1.21.  Set or Get the SCTP Partial Delivery Point
3084  *       (SCTP_PARTIAL_DELIVERY_POINT)
3085  *
3086  * This option will set or get the SCTP partial delivery point.  This
3087  * point is the size of a message where the partial delivery API will be
3088  * invoked to help free up rwnd space for the peer.  Setting this to a
3089  * lower value will cause partial deliveries to happen more often.  The
3090  * calls argument is an integer that sets or gets the partial delivery
3091  * point.  Note also that the call will fail if the user attempts to set
3092  * this value larger than the socket receive buffer size.
3093  *
3094  * Note that any single message having a length smaller than or equal to
3095  * the SCTP partial delivery point will be delivered in one single read
3096  * call as long as the user provided buffer is large enough to hold the
3097  * message.
3098  */
3099 static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
3100 						  char __user *optval,
3101 						  unsigned int optlen)
3102 {
3103 	u32 val;
3104 
3105 	if (optlen != sizeof(u32))
3106 		return -EINVAL;
3107 	if (get_user(val, (int __user *)optval))
3108 		return -EFAULT;
3109 
3110 	/* Note: We double the receive buffer from what the user sets
3111 	 * it to be, also initial rwnd is based on rcvbuf/2.
3112 	 */
3113 	if (val > (sk->sk_rcvbuf >> 1))
3114 		return -EINVAL;
3115 
3116 	sctp_sk(sk)->pd_point = val;
3117 
3118 	return 0; /* is this the right error code? */
3119 }
3120 
3121 /*
3122  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
3123  *
3124  * This option will allow a user to change the maximum burst of packets
3125  * that can be emitted by this association.  Note that the default value
3126  * is 4, and some implementations may restrict this setting so that it
3127  * can only be lowered.
3128  *
3129  * NOTE: This text doesn't seem right.  Do this on a socket basis with
3130  * future associations inheriting the socket value.
3131  */
3132 static int sctp_setsockopt_maxburst(struct sock *sk,
3133 				    char __user *optval,
3134 				    unsigned int optlen)
3135 {
3136 	struct sctp_assoc_value params;
3137 	struct sctp_sock *sp;
3138 	struct sctp_association *asoc;
3139 	int val;
3140 	int assoc_id = 0;
3141 
3142 	if (optlen == sizeof(int)) {
3143 		pr_warn("Use of int in max_burst socket option deprecated\n");
3144 		pr_warn("Use struct sctp_assoc_value instead\n");
3145 		if (copy_from_user(&val, optval, optlen))
3146 			return -EFAULT;
3147 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
3148 		if (copy_from_user(&params, optval, optlen))
3149 			return -EFAULT;
3150 		val = params.assoc_value;
3151 		assoc_id = params.assoc_id;
3152 	} else
3153 		return -EINVAL;
3154 
3155 	sp = sctp_sk(sk);
3156 
3157 	if (assoc_id != 0) {
3158 		asoc = sctp_id2assoc(sk, assoc_id);
3159 		if (!asoc)
3160 			return -EINVAL;
3161 		asoc->max_burst = val;
3162 	} else
3163 		sp->max_burst = val;
3164 
3165 	return 0;
3166 }
3167 
3168 /*
3169  * 7.1.18.  Add a chunk that must be authenticated (SCTP_AUTH_CHUNK)
3170  *
3171  * This set option adds a chunk type that the user is requesting to be
3172  * received only in an authenticated way.  Changes to the list of chunks
3173  * will only effect future associations on the socket.
3174  */
3175 static int sctp_setsockopt_auth_chunk(struct sock *sk,
3176 				      char __user *optval,
3177 				      unsigned int optlen)
3178 {
3179 	struct sctp_authchunk val;
3180 
3181 	if (!sctp_auth_enable)
3182 		return -EACCES;
3183 
3184 	if (optlen != sizeof(struct sctp_authchunk))
3185 		return -EINVAL;
3186 	if (copy_from_user(&val, optval, optlen))
3187 		return -EFAULT;
3188 
3189 	switch (val.sauth_chunk) {
3190 		case SCTP_CID_INIT:
3191 		case SCTP_CID_INIT_ACK:
3192 		case SCTP_CID_SHUTDOWN_COMPLETE:
3193 		case SCTP_CID_AUTH:
3194 			return -EINVAL;
3195 	}
3196 
3197 	/* add this chunk id to the endpoint */
3198 	return sctp_auth_ep_add_chunkid(sctp_sk(sk)->ep, val.sauth_chunk);
3199 }
3200 
3201 /*
3202  * 7.1.19.  Get or set the list of supported HMAC Identifiers (SCTP_HMAC_IDENT)
3203  *
3204  * This option gets or sets the list of HMAC algorithms that the local
3205  * endpoint requires the peer to use.
3206  */
3207 static int sctp_setsockopt_hmac_ident(struct sock *sk,
3208 				      char __user *optval,
3209 				      unsigned int optlen)
3210 {
3211 	struct sctp_hmacalgo *hmacs;
3212 	u32 idents;
3213 	int err;
3214 
3215 	if (!sctp_auth_enable)
3216 		return -EACCES;
3217 
3218 	if (optlen < sizeof(struct sctp_hmacalgo))
3219 		return -EINVAL;
3220 
3221 	hmacs= memdup_user(optval, optlen);
3222 	if (IS_ERR(hmacs))
3223 		return PTR_ERR(hmacs);
3224 
3225 	idents = hmacs->shmac_num_idents;
3226 	if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS ||
3227 	    (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo))) {
3228 		err = -EINVAL;
3229 		goto out;
3230 	}
3231 
3232 	err = sctp_auth_ep_set_hmacs(sctp_sk(sk)->ep, hmacs);
3233 out:
3234 	kfree(hmacs);
3235 	return err;
3236 }
3237 
3238 /*
3239  * 7.1.20.  Set a shared key (SCTP_AUTH_KEY)
3240  *
3241  * This option will set a shared secret key which is used to build an
3242  * association shared key.
3243  */
3244 static int sctp_setsockopt_auth_key(struct sock *sk,
3245 				    char __user *optval,
3246 				    unsigned int optlen)
3247 {
3248 	struct sctp_authkey *authkey;
3249 	struct sctp_association *asoc;
3250 	int ret;
3251 
3252 	if (!sctp_auth_enable)
3253 		return -EACCES;
3254 
3255 	if (optlen <= sizeof(struct sctp_authkey))
3256 		return -EINVAL;
3257 
3258 	authkey= memdup_user(optval, optlen);
3259 	if (IS_ERR(authkey))
3260 		return PTR_ERR(authkey);
3261 
3262 	if (authkey->sca_keylength > optlen - sizeof(struct sctp_authkey)) {
3263 		ret = -EINVAL;
3264 		goto out;
3265 	}
3266 
3267 	asoc = sctp_id2assoc(sk, authkey->sca_assoc_id);
3268 	if (!asoc && authkey->sca_assoc_id && sctp_style(sk, UDP)) {
3269 		ret = -EINVAL;
3270 		goto out;
3271 	}
3272 
3273 	ret = sctp_auth_set_key(sctp_sk(sk)->ep, asoc, authkey);
3274 out:
3275 	kfree(authkey);
3276 	return ret;
3277 }
3278 
3279 /*
3280  * 7.1.21.  Get or set the active shared key (SCTP_AUTH_ACTIVE_KEY)
3281  *
3282  * This option will get or set the active shared key to be used to build
3283  * the association shared key.
3284  */
3285 static int sctp_setsockopt_active_key(struct sock *sk,
3286 				      char __user *optval,
3287 				      unsigned int optlen)
3288 {
3289 	struct sctp_authkeyid val;
3290 	struct sctp_association *asoc;
3291 
3292 	if (!sctp_auth_enable)
3293 		return -EACCES;
3294 
3295 	if (optlen != sizeof(struct sctp_authkeyid))
3296 		return -EINVAL;
3297 	if (copy_from_user(&val, optval, optlen))
3298 		return -EFAULT;
3299 
3300 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3301 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3302 		return -EINVAL;
3303 
3304 	return sctp_auth_set_active_key(sctp_sk(sk)->ep, asoc,
3305 					val.scact_keynumber);
3306 }
3307 
3308 /*
3309  * 7.1.22.  Delete a shared key (SCTP_AUTH_DELETE_KEY)
3310  *
3311  * This set option will delete a shared secret key from use.
3312  */
3313 static int sctp_setsockopt_del_key(struct sock *sk,
3314 				   char __user *optval,
3315 				   unsigned int optlen)
3316 {
3317 	struct sctp_authkeyid val;
3318 	struct sctp_association *asoc;
3319 
3320 	if (!sctp_auth_enable)
3321 		return -EACCES;
3322 
3323 	if (optlen != sizeof(struct sctp_authkeyid))
3324 		return -EINVAL;
3325 	if (copy_from_user(&val, optval, optlen))
3326 		return -EFAULT;
3327 
3328 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3329 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3330 		return -EINVAL;
3331 
3332 	return sctp_auth_del_key_id(sctp_sk(sk)->ep, asoc,
3333 				    val.scact_keynumber);
3334 
3335 }
3336 
3337 
3338 /* API 6.2 setsockopt(), getsockopt()
3339  *
3340  * Applications use setsockopt() and getsockopt() to set or retrieve
3341  * socket options.  Socket options are used to change the default
3342  * behavior of sockets calls.  They are described in Section 7.
3343  *
3344  * The syntax is:
3345  *
3346  *   ret = getsockopt(int sd, int level, int optname, void __user *optval,
3347  *                    int __user *optlen);
3348  *   ret = setsockopt(int sd, int level, int optname, const void __user *optval,
3349  *                    int optlen);
3350  *
3351  *   sd      - the socket descript.
3352  *   level   - set to IPPROTO_SCTP for all SCTP options.
3353  *   optname - the option name.
3354  *   optval  - the buffer to store the value of the option.
3355  *   optlen  - the size of the buffer.
3356  */
3357 SCTP_STATIC int sctp_setsockopt(struct sock *sk, int level, int optname,
3358 				char __user *optval, unsigned int optlen)
3359 {
3360 	int retval = 0;
3361 
3362 	SCTP_DEBUG_PRINTK("sctp_setsockopt(sk: %p... optname: %d)\n",
3363 			  sk, optname);
3364 
3365 	/* I can hardly begin to describe how wrong this is.  This is
3366 	 * so broken as to be worse than useless.  The API draft
3367 	 * REALLY is NOT helpful here...  I am not convinced that the
3368 	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
3369 	 * are at all well-founded.
3370 	 */
3371 	if (level != SOL_SCTP) {
3372 		struct sctp_af *af = sctp_sk(sk)->pf->af;
3373 		retval = af->setsockopt(sk, level, optname, optval, optlen);
3374 		goto out_nounlock;
3375 	}
3376 
3377 	sctp_lock_sock(sk);
3378 
3379 	switch (optname) {
3380 	case SCTP_SOCKOPT_BINDX_ADD:
3381 		/* 'optlen' is the size of the addresses buffer. */
3382 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3383 					       optlen, SCTP_BINDX_ADD_ADDR);
3384 		break;
3385 
3386 	case SCTP_SOCKOPT_BINDX_REM:
3387 		/* 'optlen' is the size of the addresses buffer. */
3388 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3389 					       optlen, SCTP_BINDX_REM_ADDR);
3390 		break;
3391 
3392 	case SCTP_SOCKOPT_CONNECTX_OLD:
3393 		/* 'optlen' is the size of the addresses buffer. */
3394 		retval = sctp_setsockopt_connectx_old(sk,
3395 					    (struct sockaddr __user *)optval,
3396 					    optlen);
3397 		break;
3398 
3399 	case SCTP_SOCKOPT_CONNECTX:
3400 		/* 'optlen' is the size of the addresses buffer. */
3401 		retval = sctp_setsockopt_connectx(sk,
3402 					    (struct sockaddr __user *)optval,
3403 					    optlen);
3404 		break;
3405 
3406 	case SCTP_DISABLE_FRAGMENTS:
3407 		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
3408 		break;
3409 
3410 	case SCTP_EVENTS:
3411 		retval = sctp_setsockopt_events(sk, optval, optlen);
3412 		break;
3413 
3414 	case SCTP_AUTOCLOSE:
3415 		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
3416 		break;
3417 
3418 	case SCTP_PEER_ADDR_PARAMS:
3419 		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
3420 		break;
3421 
3422 	case SCTP_DELAYED_SACK:
3423 		retval = sctp_setsockopt_delayed_ack(sk, optval, optlen);
3424 		break;
3425 	case SCTP_PARTIAL_DELIVERY_POINT:
3426 		retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
3427 		break;
3428 
3429 	case SCTP_INITMSG:
3430 		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
3431 		break;
3432 	case SCTP_DEFAULT_SEND_PARAM:
3433 		retval = sctp_setsockopt_default_send_param(sk, optval,
3434 							    optlen);
3435 		break;
3436 	case SCTP_PRIMARY_ADDR:
3437 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
3438 		break;
3439 	case SCTP_SET_PEER_PRIMARY_ADDR:
3440 		retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
3441 		break;
3442 	case SCTP_NODELAY:
3443 		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
3444 		break;
3445 	case SCTP_RTOINFO:
3446 		retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
3447 		break;
3448 	case SCTP_ASSOCINFO:
3449 		retval = sctp_setsockopt_associnfo(sk, optval, optlen);
3450 		break;
3451 	case SCTP_I_WANT_MAPPED_V4_ADDR:
3452 		retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
3453 		break;
3454 	case SCTP_MAXSEG:
3455 		retval = sctp_setsockopt_maxseg(sk, optval, optlen);
3456 		break;
3457 	case SCTP_ADAPTATION_LAYER:
3458 		retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
3459 		break;
3460 	case SCTP_CONTEXT:
3461 		retval = sctp_setsockopt_context(sk, optval, optlen);
3462 		break;
3463 	case SCTP_FRAGMENT_INTERLEAVE:
3464 		retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
3465 		break;
3466 	case SCTP_MAX_BURST:
3467 		retval = sctp_setsockopt_maxburst(sk, optval, optlen);
3468 		break;
3469 	case SCTP_AUTH_CHUNK:
3470 		retval = sctp_setsockopt_auth_chunk(sk, optval, optlen);
3471 		break;
3472 	case SCTP_HMAC_IDENT:
3473 		retval = sctp_setsockopt_hmac_ident(sk, optval, optlen);
3474 		break;
3475 	case SCTP_AUTH_KEY:
3476 		retval = sctp_setsockopt_auth_key(sk, optval, optlen);
3477 		break;
3478 	case SCTP_AUTH_ACTIVE_KEY:
3479 		retval = sctp_setsockopt_active_key(sk, optval, optlen);
3480 		break;
3481 	case SCTP_AUTH_DELETE_KEY:
3482 		retval = sctp_setsockopt_del_key(sk, optval, optlen);
3483 		break;
3484 	default:
3485 		retval = -ENOPROTOOPT;
3486 		break;
3487 	}
3488 
3489 	sctp_release_sock(sk);
3490 
3491 out_nounlock:
3492 	return retval;
3493 }
3494 
3495 /* API 3.1.6 connect() - UDP Style Syntax
3496  *
3497  * An application may use the connect() call in the UDP model to initiate an
3498  * association without sending data.
3499  *
3500  * The syntax is:
3501  *
3502  * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
3503  *
3504  * sd: the socket descriptor to have a new association added to.
3505  *
3506  * nam: the address structure (either struct sockaddr_in or struct
3507  *    sockaddr_in6 defined in RFC2553 [7]).
3508  *
3509  * len: the size of the address.
3510  */
3511 SCTP_STATIC int sctp_connect(struct sock *sk, struct sockaddr *addr,
3512 			     int addr_len)
3513 {
3514 	int err = 0;
3515 	struct sctp_af *af;
3516 
3517 	sctp_lock_sock(sk);
3518 
3519 	SCTP_DEBUG_PRINTK("%s - sk: %p, sockaddr: %p, addr_len: %d\n",
3520 			  __func__, sk, addr, addr_len);
3521 
3522 	/* Validate addr_len before calling common connect/connectx routine. */
3523 	af = sctp_get_af_specific(addr->sa_family);
3524 	if (!af || addr_len < af->sockaddr_len) {
3525 		err = -EINVAL;
3526 	} else {
3527 		/* Pass correct addr len to common routine (so it knows there
3528 		 * is only one address being passed.
3529 		 */
3530 		err = __sctp_connect(sk, addr, af->sockaddr_len, NULL);
3531 	}
3532 
3533 	sctp_release_sock(sk);
3534 	return err;
3535 }
3536 
3537 /* FIXME: Write comments. */
3538 SCTP_STATIC int sctp_disconnect(struct sock *sk, int flags)
3539 {
3540 	return -EOPNOTSUPP; /* STUB */
3541 }
3542 
3543 /* 4.1.4 accept() - TCP Style Syntax
3544  *
3545  * Applications use accept() call to remove an established SCTP
3546  * association from the accept queue of the endpoint.  A new socket
3547  * descriptor will be returned from accept() to represent the newly
3548  * formed association.
3549  */
3550 SCTP_STATIC struct sock *sctp_accept(struct sock *sk, int flags, int *err)
3551 {
3552 	struct sctp_sock *sp;
3553 	struct sctp_endpoint *ep;
3554 	struct sock *newsk = NULL;
3555 	struct sctp_association *asoc;
3556 	long timeo;
3557 	int error = 0;
3558 
3559 	sctp_lock_sock(sk);
3560 
3561 	sp = sctp_sk(sk);
3562 	ep = sp->ep;
3563 
3564 	if (!sctp_style(sk, TCP)) {
3565 		error = -EOPNOTSUPP;
3566 		goto out;
3567 	}
3568 
3569 	if (!sctp_sstate(sk, LISTENING)) {
3570 		error = -EINVAL;
3571 		goto out;
3572 	}
3573 
3574 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
3575 
3576 	error = sctp_wait_for_accept(sk, timeo);
3577 	if (error)
3578 		goto out;
3579 
3580 	/* We treat the list of associations on the endpoint as the accept
3581 	 * queue and pick the first association on the list.
3582 	 */
3583 	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
3584 
3585 	newsk = sp->pf->create_accept_sk(sk, asoc);
3586 	if (!newsk) {
3587 		error = -ENOMEM;
3588 		goto out;
3589 	}
3590 
3591 	/* Populate the fields of the newsk from the oldsk and migrate the
3592 	 * asoc to the newsk.
3593 	 */
3594 	sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
3595 
3596 out:
3597 	sctp_release_sock(sk);
3598 	*err = error;
3599 	return newsk;
3600 }
3601 
3602 /* The SCTP ioctl handler. */
3603 SCTP_STATIC int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
3604 {
3605 	int rc = -ENOTCONN;
3606 
3607 	sctp_lock_sock(sk);
3608 
3609 	/*
3610 	 * SEQPACKET-style sockets in LISTENING state are valid, for
3611 	 * SCTP, so only discard TCP-style sockets in LISTENING state.
3612 	 */
3613 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
3614 		goto out;
3615 
3616 	switch (cmd) {
3617 	case SIOCINQ: {
3618 		struct sk_buff *skb;
3619 		unsigned int amount = 0;
3620 
3621 		skb = skb_peek(&sk->sk_receive_queue);
3622 		if (skb != NULL) {
3623 			/*
3624 			 * We will only return the amount of this packet since
3625 			 * that is all that will be read.
3626 			 */
3627 			amount = skb->len;
3628 		}
3629 		rc = put_user(amount, (int __user *)arg);
3630 		break;
3631 	}
3632 	default:
3633 		rc = -ENOIOCTLCMD;
3634 		break;
3635 	}
3636 out:
3637 	sctp_release_sock(sk);
3638 	return rc;
3639 }
3640 
3641 /* This is the function which gets called during socket creation to
3642  * initialized the SCTP-specific portion of the sock.
3643  * The sock structure should already be zero-filled memory.
3644  */
3645 SCTP_STATIC int sctp_init_sock(struct sock *sk)
3646 {
3647 	struct sctp_endpoint *ep;
3648 	struct sctp_sock *sp;
3649 
3650 	SCTP_DEBUG_PRINTK("sctp_init_sock(sk: %p)\n", sk);
3651 
3652 	sp = sctp_sk(sk);
3653 
3654 	/* Initialize the SCTP per socket area.  */
3655 	switch (sk->sk_type) {
3656 	case SOCK_SEQPACKET:
3657 		sp->type = SCTP_SOCKET_UDP;
3658 		break;
3659 	case SOCK_STREAM:
3660 		sp->type = SCTP_SOCKET_TCP;
3661 		break;
3662 	default:
3663 		return -ESOCKTNOSUPPORT;
3664 	}
3665 
3666 	/* Initialize default send parameters. These parameters can be
3667 	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
3668 	 */
3669 	sp->default_stream = 0;
3670 	sp->default_ppid = 0;
3671 	sp->default_flags = 0;
3672 	sp->default_context = 0;
3673 	sp->default_timetolive = 0;
3674 
3675 	sp->default_rcv_context = 0;
3676 	sp->max_burst = sctp_max_burst;
3677 
3678 	/* Initialize default setup parameters. These parameters
3679 	 * can be modified with the SCTP_INITMSG socket option or
3680 	 * overridden by the SCTP_INIT CMSG.
3681 	 */
3682 	sp->initmsg.sinit_num_ostreams   = sctp_max_outstreams;
3683 	sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
3684 	sp->initmsg.sinit_max_attempts   = sctp_max_retrans_init;
3685 	sp->initmsg.sinit_max_init_timeo = sctp_rto_max;
3686 
3687 	/* Initialize default RTO related parameters.  These parameters can
3688 	 * be modified for with the SCTP_RTOINFO socket option.
3689 	 */
3690 	sp->rtoinfo.srto_initial = sctp_rto_initial;
3691 	sp->rtoinfo.srto_max     = sctp_rto_max;
3692 	sp->rtoinfo.srto_min     = sctp_rto_min;
3693 
3694 	/* Initialize default association related parameters. These parameters
3695 	 * can be modified with the SCTP_ASSOCINFO socket option.
3696 	 */
3697 	sp->assocparams.sasoc_asocmaxrxt = sctp_max_retrans_association;
3698 	sp->assocparams.sasoc_number_peer_destinations = 0;
3699 	sp->assocparams.sasoc_peer_rwnd = 0;
3700 	sp->assocparams.sasoc_local_rwnd = 0;
3701 	sp->assocparams.sasoc_cookie_life = sctp_valid_cookie_life;
3702 
3703 	/* Initialize default event subscriptions. By default, all the
3704 	 * options are off.
3705 	 */
3706 	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
3707 
3708 	/* Default Peer Address Parameters.  These defaults can
3709 	 * be modified via SCTP_PEER_ADDR_PARAMS
3710 	 */
3711 	sp->hbinterval  = sctp_hb_interval;
3712 	sp->pathmaxrxt  = sctp_max_retrans_path;
3713 	sp->pathmtu     = 0; // allow default discovery
3714 	sp->sackdelay   = sctp_sack_timeout;
3715 	sp->sackfreq	= 2;
3716 	sp->param_flags = SPP_HB_ENABLE |
3717 			  SPP_PMTUD_ENABLE |
3718 			  SPP_SACKDELAY_ENABLE;
3719 
3720 	/* If enabled no SCTP message fragmentation will be performed.
3721 	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
3722 	 */
3723 	sp->disable_fragments = 0;
3724 
3725 	/* Enable Nagle algorithm by default.  */
3726 	sp->nodelay           = 0;
3727 
3728 	/* Enable by default. */
3729 	sp->v4mapped          = 1;
3730 
3731 	/* Auto-close idle associations after the configured
3732 	 * number of seconds.  A value of 0 disables this
3733 	 * feature.  Configure through the SCTP_AUTOCLOSE socket option,
3734 	 * for UDP-style sockets only.
3735 	 */
3736 	sp->autoclose         = 0;
3737 
3738 	/* User specified fragmentation limit. */
3739 	sp->user_frag         = 0;
3740 
3741 	sp->adaptation_ind = 0;
3742 
3743 	sp->pf = sctp_get_pf_specific(sk->sk_family);
3744 
3745 	/* Control variables for partial data delivery. */
3746 	atomic_set(&sp->pd_mode, 0);
3747 	skb_queue_head_init(&sp->pd_lobby);
3748 	sp->frag_interleave = 0;
3749 
3750 	/* Create a per socket endpoint structure.  Even if we
3751 	 * change the data structure relationships, this may still
3752 	 * be useful for storing pre-connect address information.
3753 	 */
3754 	ep = sctp_endpoint_new(sk, GFP_KERNEL);
3755 	if (!ep)
3756 		return -ENOMEM;
3757 
3758 	sp->ep = ep;
3759 	sp->hmac = NULL;
3760 
3761 	SCTP_DBG_OBJCNT_INC(sock);
3762 
3763 	local_bh_disable();
3764 	percpu_counter_inc(&sctp_sockets_allocated);
3765 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
3766 	local_bh_enable();
3767 
3768 	return 0;
3769 }
3770 
3771 /* Cleanup any SCTP per socket resources.  */
3772 SCTP_STATIC void sctp_destroy_sock(struct sock *sk)
3773 {
3774 	struct sctp_endpoint *ep;
3775 
3776 	SCTP_DEBUG_PRINTK("sctp_destroy_sock(sk: %p)\n", sk);
3777 
3778 	/* Release our hold on the endpoint. */
3779 	ep = sctp_sk(sk)->ep;
3780 	sctp_endpoint_free(ep);
3781 	local_bh_disable();
3782 	percpu_counter_dec(&sctp_sockets_allocated);
3783 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
3784 	local_bh_enable();
3785 }
3786 
3787 /* API 4.1.7 shutdown() - TCP Style Syntax
3788  *     int shutdown(int socket, int how);
3789  *
3790  *     sd      - the socket descriptor of the association to be closed.
3791  *     how     - Specifies the type of shutdown.  The  values  are
3792  *               as follows:
3793  *               SHUT_RD
3794  *                     Disables further receive operations. No SCTP
3795  *                     protocol action is taken.
3796  *               SHUT_WR
3797  *                     Disables further send operations, and initiates
3798  *                     the SCTP shutdown sequence.
3799  *               SHUT_RDWR
3800  *                     Disables further send  and  receive  operations
3801  *                     and initiates the SCTP shutdown sequence.
3802  */
3803 SCTP_STATIC void sctp_shutdown(struct sock *sk, int how)
3804 {
3805 	struct sctp_endpoint *ep;
3806 	struct sctp_association *asoc;
3807 
3808 	if (!sctp_style(sk, TCP))
3809 		return;
3810 
3811 	if (how & SEND_SHUTDOWN) {
3812 		ep = sctp_sk(sk)->ep;
3813 		if (!list_empty(&ep->asocs)) {
3814 			asoc = list_entry(ep->asocs.next,
3815 					  struct sctp_association, asocs);
3816 			sctp_primitive_SHUTDOWN(asoc, NULL);
3817 		}
3818 	}
3819 }
3820 
3821 /* 7.2.1 Association Status (SCTP_STATUS)
3822 
3823  * Applications can retrieve current status information about an
3824  * association, including association state, peer receiver window size,
3825  * number of unacked data chunks, and number of data chunks pending
3826  * receipt.  This information is read-only.
3827  */
3828 static int sctp_getsockopt_sctp_status(struct sock *sk, int len,
3829 				       char __user *optval,
3830 				       int __user *optlen)
3831 {
3832 	struct sctp_status status;
3833 	struct sctp_association *asoc = NULL;
3834 	struct sctp_transport *transport;
3835 	sctp_assoc_t associd;
3836 	int retval = 0;
3837 
3838 	if (len < sizeof(status)) {
3839 		retval = -EINVAL;
3840 		goto out;
3841 	}
3842 
3843 	len = sizeof(status);
3844 	if (copy_from_user(&status, optval, len)) {
3845 		retval = -EFAULT;
3846 		goto out;
3847 	}
3848 
3849 	associd = status.sstat_assoc_id;
3850 	asoc = sctp_id2assoc(sk, associd);
3851 	if (!asoc) {
3852 		retval = -EINVAL;
3853 		goto out;
3854 	}
3855 
3856 	transport = asoc->peer.primary_path;
3857 
3858 	status.sstat_assoc_id = sctp_assoc2id(asoc);
3859 	status.sstat_state = asoc->state;
3860 	status.sstat_rwnd =  asoc->peer.rwnd;
3861 	status.sstat_unackdata = asoc->unack_data;
3862 
3863 	status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
3864 	status.sstat_instrms = asoc->c.sinit_max_instreams;
3865 	status.sstat_outstrms = asoc->c.sinit_num_ostreams;
3866 	status.sstat_fragmentation_point = asoc->frag_point;
3867 	status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3868 	memcpy(&status.sstat_primary.spinfo_address, &transport->ipaddr,
3869 			transport->af_specific->sockaddr_len);
3870 	/* Map ipv4 address into v4-mapped-on-v6 address.  */
3871 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
3872 		(union sctp_addr *)&status.sstat_primary.spinfo_address);
3873 	status.sstat_primary.spinfo_state = transport->state;
3874 	status.sstat_primary.spinfo_cwnd = transport->cwnd;
3875 	status.sstat_primary.spinfo_srtt = transport->srtt;
3876 	status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
3877 	status.sstat_primary.spinfo_mtu = transport->pathmtu;
3878 
3879 	if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
3880 		status.sstat_primary.spinfo_state = SCTP_ACTIVE;
3881 
3882 	if (put_user(len, optlen)) {
3883 		retval = -EFAULT;
3884 		goto out;
3885 	}
3886 
3887 	SCTP_DEBUG_PRINTK("sctp_getsockopt_sctp_status(%d): %d %d %d\n",
3888 			  len, status.sstat_state, status.sstat_rwnd,
3889 			  status.sstat_assoc_id);
3890 
3891 	if (copy_to_user(optval, &status, len)) {
3892 		retval = -EFAULT;
3893 		goto out;
3894 	}
3895 
3896 out:
3897 	return retval;
3898 }
3899 
3900 
3901 /* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
3902  *
3903  * Applications can retrieve information about a specific peer address
3904  * of an association, including its reachability state, congestion
3905  * window, and retransmission timer values.  This information is
3906  * read-only.
3907  */
3908 static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
3909 					  char __user *optval,
3910 					  int __user *optlen)
3911 {
3912 	struct sctp_paddrinfo pinfo;
3913 	struct sctp_transport *transport;
3914 	int retval = 0;
3915 
3916 	if (len < sizeof(pinfo)) {
3917 		retval = -EINVAL;
3918 		goto out;
3919 	}
3920 
3921 	len = sizeof(pinfo);
3922 	if (copy_from_user(&pinfo, optval, len)) {
3923 		retval = -EFAULT;
3924 		goto out;
3925 	}
3926 
3927 	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
3928 					   pinfo.spinfo_assoc_id);
3929 	if (!transport)
3930 		return -EINVAL;
3931 
3932 	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3933 	pinfo.spinfo_state = transport->state;
3934 	pinfo.spinfo_cwnd = transport->cwnd;
3935 	pinfo.spinfo_srtt = transport->srtt;
3936 	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
3937 	pinfo.spinfo_mtu = transport->pathmtu;
3938 
3939 	if (pinfo.spinfo_state == SCTP_UNKNOWN)
3940 		pinfo.spinfo_state = SCTP_ACTIVE;
3941 
3942 	if (put_user(len, optlen)) {
3943 		retval = -EFAULT;
3944 		goto out;
3945 	}
3946 
3947 	if (copy_to_user(optval, &pinfo, len)) {
3948 		retval = -EFAULT;
3949 		goto out;
3950 	}
3951 
3952 out:
3953 	return retval;
3954 }
3955 
3956 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
3957  *
3958  * This option is a on/off flag.  If enabled no SCTP message
3959  * fragmentation will be performed.  Instead if a message being sent
3960  * exceeds the current PMTU size, the message will NOT be sent and
3961  * instead a error will be indicated to the user.
3962  */
3963 static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
3964 					char __user *optval, int __user *optlen)
3965 {
3966 	int val;
3967 
3968 	if (len < sizeof(int))
3969 		return -EINVAL;
3970 
3971 	len = sizeof(int);
3972 	val = (sctp_sk(sk)->disable_fragments == 1);
3973 	if (put_user(len, optlen))
3974 		return -EFAULT;
3975 	if (copy_to_user(optval, &val, len))
3976 		return -EFAULT;
3977 	return 0;
3978 }
3979 
3980 /* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
3981  *
3982  * This socket option is used to specify various notifications and
3983  * ancillary data the user wishes to receive.
3984  */
3985 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
3986 				  int __user *optlen)
3987 {
3988 	if (len < sizeof(struct sctp_event_subscribe))
3989 		return -EINVAL;
3990 	len = sizeof(struct sctp_event_subscribe);
3991 	if (put_user(len, optlen))
3992 		return -EFAULT;
3993 	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
3994 		return -EFAULT;
3995 	return 0;
3996 }
3997 
3998 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
3999  *
4000  * This socket option is applicable to the UDP-style socket only.  When
4001  * set it will cause associations that are idle for more than the
4002  * specified number of seconds to automatically close.  An association
4003  * being idle is defined an association that has NOT sent or received
4004  * user data.  The special value of '0' indicates that no automatic
4005  * close of any associations should be performed.  The option expects an
4006  * integer defining the number of seconds of idle time before an
4007  * association is closed.
4008  */
4009 static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
4010 {
4011 	/* Applicable to UDP-style socket only */
4012 	if (sctp_style(sk, TCP))
4013 		return -EOPNOTSUPP;
4014 	if (len < sizeof(int))
4015 		return -EINVAL;
4016 	len = sizeof(int);
4017 	if (put_user(len, optlen))
4018 		return -EFAULT;
4019 	if (copy_to_user(optval, &sctp_sk(sk)->autoclose, sizeof(int)))
4020 		return -EFAULT;
4021 	return 0;
4022 }
4023 
4024 /* Helper routine to branch off an association to a new socket.  */
4025 SCTP_STATIC int sctp_do_peeloff(struct sctp_association *asoc,
4026 				struct socket **sockp)
4027 {
4028 	struct sock *sk = asoc->base.sk;
4029 	struct socket *sock;
4030 	struct sctp_af *af;
4031 	int err = 0;
4032 
4033 	/* An association cannot be branched off from an already peeled-off
4034 	 * socket, nor is this supported for tcp style sockets.
4035 	 */
4036 	if (!sctp_style(sk, UDP))
4037 		return -EINVAL;
4038 
4039 	/* Create a new socket.  */
4040 	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
4041 	if (err < 0)
4042 		return err;
4043 
4044 	sctp_copy_sock(sock->sk, sk, asoc);
4045 
4046 	/* Make peeled-off sockets more like 1-1 accepted sockets.
4047 	 * Set the daddr and initialize id to something more random
4048 	 */
4049 	af = sctp_get_af_specific(asoc->peer.primary_addr.sa.sa_family);
4050 	af->to_sk_daddr(&asoc->peer.primary_addr, sk);
4051 
4052 	/* Populate the fields of the newsk from the oldsk and migrate the
4053 	 * asoc to the newsk.
4054 	 */
4055 	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
4056 
4057 	*sockp = sock;
4058 
4059 	return err;
4060 }
4061 
4062 static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
4063 {
4064 	sctp_peeloff_arg_t peeloff;
4065 	struct socket *newsock;
4066 	int retval = 0;
4067 	struct sctp_association *asoc;
4068 
4069 	if (len < sizeof(sctp_peeloff_arg_t))
4070 		return -EINVAL;
4071 	len = sizeof(sctp_peeloff_arg_t);
4072 	if (copy_from_user(&peeloff, optval, len))
4073 		return -EFAULT;
4074 
4075 	asoc = sctp_id2assoc(sk, peeloff.associd);
4076 	if (!asoc) {
4077 		retval = -EINVAL;
4078 		goto out;
4079 	}
4080 
4081 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p\n", __func__, sk, asoc);
4082 
4083 	retval = sctp_do_peeloff(asoc, &newsock);
4084 	if (retval < 0)
4085 		goto out;
4086 
4087 	/* Map the socket to an unused fd that can be returned to the user.  */
4088 	retval = sock_map_fd(newsock, 0);
4089 	if (retval < 0) {
4090 		sock_release(newsock);
4091 		goto out;
4092 	}
4093 
4094 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p newsk: %p sd: %d\n",
4095 			  __func__, sk, asoc, newsock->sk, retval);
4096 
4097 	/* Return the fd mapped to the new socket.  */
4098 	peeloff.sd = retval;
4099 	if (put_user(len, optlen))
4100 		return -EFAULT;
4101 	if (copy_to_user(optval, &peeloff, len))
4102 		retval = -EFAULT;
4103 
4104 out:
4105 	return retval;
4106 }
4107 
4108 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
4109  *
4110  * Applications can enable or disable heartbeats for any peer address of
4111  * an association, modify an address's heartbeat interval, force a
4112  * heartbeat to be sent immediately, and adjust the address's maximum
4113  * number of retransmissions sent before an address is considered
4114  * unreachable.  The following structure is used to access and modify an
4115  * address's parameters:
4116  *
4117  *  struct sctp_paddrparams {
4118  *     sctp_assoc_t            spp_assoc_id;
4119  *     struct sockaddr_storage spp_address;
4120  *     uint32_t                spp_hbinterval;
4121  *     uint16_t                spp_pathmaxrxt;
4122  *     uint32_t                spp_pathmtu;
4123  *     uint32_t                spp_sackdelay;
4124  *     uint32_t                spp_flags;
4125  * };
4126  *
4127  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
4128  *                     application, and identifies the association for
4129  *                     this query.
4130  *   spp_address     - This specifies which address is of interest.
4131  *   spp_hbinterval  - This contains the value of the heartbeat interval,
4132  *                     in milliseconds.  If a  value of zero
4133  *                     is present in this field then no changes are to
4134  *                     be made to this parameter.
4135  *   spp_pathmaxrxt  - This contains the maximum number of
4136  *                     retransmissions before this address shall be
4137  *                     considered unreachable. If a  value of zero
4138  *                     is present in this field then no changes are to
4139  *                     be made to this parameter.
4140  *   spp_pathmtu     - When Path MTU discovery is disabled the value
4141  *                     specified here will be the "fixed" path mtu.
4142  *                     Note that if the spp_address field is empty
4143  *                     then all associations on this address will
4144  *                     have this fixed path mtu set upon them.
4145  *
4146  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
4147  *                     the number of milliseconds that sacks will be delayed
4148  *                     for. This value will apply to all addresses of an
4149  *                     association if the spp_address field is empty. Note
4150  *                     also, that if delayed sack is enabled and this
4151  *                     value is set to 0, no change is made to the last
4152  *                     recorded delayed sack timer value.
4153  *
4154  *   spp_flags       - These flags are used to control various features
4155  *                     on an association. The flag field may contain
4156  *                     zero or more of the following options.
4157  *
4158  *                     SPP_HB_ENABLE  - Enable heartbeats on the
4159  *                     specified address. Note that if the address
4160  *                     field is empty all addresses for the association
4161  *                     have heartbeats enabled upon them.
4162  *
4163  *                     SPP_HB_DISABLE - Disable heartbeats on the
4164  *                     speicifed address. Note that if the address
4165  *                     field is empty all addresses for the association
4166  *                     will have their heartbeats disabled. Note also
4167  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
4168  *                     mutually exclusive, only one of these two should
4169  *                     be specified. Enabling both fields will have
4170  *                     undetermined results.
4171  *
4172  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
4173  *                     to be made immediately.
4174  *
4175  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
4176  *                     discovery upon the specified address. Note that
4177  *                     if the address feild is empty then all addresses
4178  *                     on the association are effected.
4179  *
4180  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
4181  *                     discovery upon the specified address. Note that
4182  *                     if the address feild is empty then all addresses
4183  *                     on the association are effected. Not also that
4184  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
4185  *                     exclusive. Enabling both will have undetermined
4186  *                     results.
4187  *
4188  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
4189  *                     on delayed sack. The time specified in spp_sackdelay
4190  *                     is used to specify the sack delay for this address. Note
4191  *                     that if spp_address is empty then all addresses will
4192  *                     enable delayed sack and take on the sack delay
4193  *                     value specified in spp_sackdelay.
4194  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
4195  *                     off delayed sack. If the spp_address field is blank then
4196  *                     delayed sack is disabled for the entire association. Note
4197  *                     also that this field is mutually exclusive to
4198  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
4199  *                     results.
4200  */
4201 static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
4202 					    char __user *optval, int __user *optlen)
4203 {
4204 	struct sctp_paddrparams  params;
4205 	struct sctp_transport   *trans = NULL;
4206 	struct sctp_association *asoc = NULL;
4207 	struct sctp_sock        *sp = sctp_sk(sk);
4208 
4209 	if (len < sizeof(struct sctp_paddrparams))
4210 		return -EINVAL;
4211 	len = sizeof(struct sctp_paddrparams);
4212 	if (copy_from_user(&params, optval, len))
4213 		return -EFAULT;
4214 
4215 	/* If an address other than INADDR_ANY is specified, and
4216 	 * no transport is found, then the request is invalid.
4217 	 */
4218 	if (!sctp_is_any(sk, ( union sctp_addr *)&params.spp_address)) {
4219 		trans = sctp_addr_id2transport(sk, &params.spp_address,
4220 					       params.spp_assoc_id);
4221 		if (!trans) {
4222 			SCTP_DEBUG_PRINTK("Failed no transport\n");
4223 			return -EINVAL;
4224 		}
4225 	}
4226 
4227 	/* Get association, if assoc_id != 0 and the socket is a one
4228 	 * to many style socket, and an association was not found, then
4229 	 * the id was invalid.
4230 	 */
4231 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
4232 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
4233 		SCTP_DEBUG_PRINTK("Failed no association\n");
4234 		return -EINVAL;
4235 	}
4236 
4237 	if (trans) {
4238 		/* Fetch transport values. */
4239 		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
4240 		params.spp_pathmtu    = trans->pathmtu;
4241 		params.spp_pathmaxrxt = trans->pathmaxrxt;
4242 		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
4243 
4244 		/*draft-11 doesn't say what to return in spp_flags*/
4245 		params.spp_flags      = trans->param_flags;
4246 	} else if (asoc) {
4247 		/* Fetch association values. */
4248 		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
4249 		params.spp_pathmtu    = asoc->pathmtu;
4250 		params.spp_pathmaxrxt = asoc->pathmaxrxt;
4251 		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
4252 
4253 		/*draft-11 doesn't say what to return in spp_flags*/
4254 		params.spp_flags      = asoc->param_flags;
4255 	} else {
4256 		/* Fetch socket values. */
4257 		params.spp_hbinterval = sp->hbinterval;
4258 		params.spp_pathmtu    = sp->pathmtu;
4259 		params.spp_sackdelay  = sp->sackdelay;
4260 		params.spp_pathmaxrxt = sp->pathmaxrxt;
4261 
4262 		/*draft-11 doesn't say what to return in spp_flags*/
4263 		params.spp_flags      = sp->param_flags;
4264 	}
4265 
4266 	if (copy_to_user(optval, &params, len))
4267 		return -EFAULT;
4268 
4269 	if (put_user(len, optlen))
4270 		return -EFAULT;
4271 
4272 	return 0;
4273 }
4274 
4275 /*
4276  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
4277  *
4278  * This option will effect the way delayed acks are performed.  This
4279  * option allows you to get or set the delayed ack time, in
4280  * milliseconds.  It also allows changing the delayed ack frequency.
4281  * Changing the frequency to 1 disables the delayed sack algorithm.  If
4282  * the assoc_id is 0, then this sets or gets the endpoints default
4283  * values.  If the assoc_id field is non-zero, then the set or get
4284  * effects the specified association for the one to many model (the
4285  * assoc_id field is ignored by the one to one model).  Note that if
4286  * sack_delay or sack_freq are 0 when setting this option, then the
4287  * current values will remain unchanged.
4288  *
4289  * struct sctp_sack_info {
4290  *     sctp_assoc_t            sack_assoc_id;
4291  *     uint32_t                sack_delay;
4292  *     uint32_t                sack_freq;
4293  * };
4294  *
4295  * sack_assoc_id -  This parameter, indicates which association the user
4296  *    is performing an action upon.  Note that if this field's value is
4297  *    zero then the endpoints default value is changed (effecting future
4298  *    associations only).
4299  *
4300  * sack_delay -  This parameter contains the number of milliseconds that
4301  *    the user is requesting the delayed ACK timer be set to.  Note that
4302  *    this value is defined in the standard to be between 200 and 500
4303  *    milliseconds.
4304  *
4305  * sack_freq -  This parameter contains the number of packets that must
4306  *    be received before a sack is sent without waiting for the delay
4307  *    timer to expire.  The default value for this is 2, setting this
4308  *    value to 1 will disable the delayed sack algorithm.
4309  */
4310 static int sctp_getsockopt_delayed_ack(struct sock *sk, int len,
4311 					    char __user *optval,
4312 					    int __user *optlen)
4313 {
4314 	struct sctp_sack_info    params;
4315 	struct sctp_association *asoc = NULL;
4316 	struct sctp_sock        *sp = sctp_sk(sk);
4317 
4318 	if (len >= sizeof(struct sctp_sack_info)) {
4319 		len = sizeof(struct sctp_sack_info);
4320 
4321 		if (copy_from_user(&params, optval, len))
4322 			return -EFAULT;
4323 	} else if (len == sizeof(struct sctp_assoc_value)) {
4324 		pr_warn("Use of struct sctp_assoc_value in delayed_ack socket option deprecated\n");
4325 		pr_warn("Use struct sctp_sack_info instead\n");
4326 		if (copy_from_user(&params, optval, len))
4327 			return -EFAULT;
4328 	} else
4329 		return - EINVAL;
4330 
4331 	/* Get association, if sack_assoc_id != 0 and the socket is a one
4332 	 * to many style socket, and an association was not found, then
4333 	 * the id was invalid.
4334 	 */
4335 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
4336 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
4337 		return -EINVAL;
4338 
4339 	if (asoc) {
4340 		/* Fetch association values. */
4341 		if (asoc->param_flags & SPP_SACKDELAY_ENABLE) {
4342 			params.sack_delay = jiffies_to_msecs(
4343 				asoc->sackdelay);
4344 			params.sack_freq = asoc->sackfreq;
4345 
4346 		} else {
4347 			params.sack_delay = 0;
4348 			params.sack_freq = 1;
4349 		}
4350 	} else {
4351 		/* Fetch socket values. */
4352 		if (sp->param_flags & SPP_SACKDELAY_ENABLE) {
4353 			params.sack_delay  = sp->sackdelay;
4354 			params.sack_freq = sp->sackfreq;
4355 		} else {
4356 			params.sack_delay  = 0;
4357 			params.sack_freq = 1;
4358 		}
4359 	}
4360 
4361 	if (copy_to_user(optval, &params, len))
4362 		return -EFAULT;
4363 
4364 	if (put_user(len, optlen))
4365 		return -EFAULT;
4366 
4367 	return 0;
4368 }
4369 
4370 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
4371  *
4372  * Applications can specify protocol parameters for the default association
4373  * initialization.  The option name argument to setsockopt() and getsockopt()
4374  * is SCTP_INITMSG.
4375  *
4376  * Setting initialization parameters is effective only on an unconnected
4377  * socket (for UDP-style sockets only future associations are effected
4378  * by the change).  With TCP-style sockets, this option is inherited by
4379  * sockets derived from a listener socket.
4380  */
4381 static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
4382 {
4383 	if (len < sizeof(struct sctp_initmsg))
4384 		return -EINVAL;
4385 	len = sizeof(struct sctp_initmsg);
4386 	if (put_user(len, optlen))
4387 		return -EFAULT;
4388 	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
4389 		return -EFAULT;
4390 	return 0;
4391 }
4392 
4393 
4394 static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
4395 				      char __user *optval, int __user *optlen)
4396 {
4397 	struct sctp_association *asoc;
4398 	int cnt = 0;
4399 	struct sctp_getaddrs getaddrs;
4400 	struct sctp_transport *from;
4401 	void __user *to;
4402 	union sctp_addr temp;
4403 	struct sctp_sock *sp = sctp_sk(sk);
4404 	int addrlen;
4405 	size_t space_left;
4406 	int bytes_copied;
4407 
4408 	if (len < sizeof(struct sctp_getaddrs))
4409 		return -EINVAL;
4410 
4411 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4412 		return -EFAULT;
4413 
4414 	/* For UDP-style sockets, id specifies the association to query.  */
4415 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4416 	if (!asoc)
4417 		return -EINVAL;
4418 
4419 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4420 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4421 
4422 	list_for_each_entry(from, &asoc->peer.transport_addr_list,
4423 				transports) {
4424 		memcpy(&temp, &from->ipaddr, sizeof(temp));
4425 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4426 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4427 		if (space_left < addrlen)
4428 			return -ENOMEM;
4429 		if (copy_to_user(to, &temp, addrlen))
4430 			return -EFAULT;
4431 		to += addrlen;
4432 		cnt++;
4433 		space_left -= addrlen;
4434 	}
4435 
4436 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
4437 		return -EFAULT;
4438 	bytes_copied = ((char __user *)to) - optval;
4439 	if (put_user(bytes_copied, optlen))
4440 		return -EFAULT;
4441 
4442 	return 0;
4443 }
4444 
4445 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
4446 			    size_t space_left, int *bytes_copied)
4447 {
4448 	struct sctp_sockaddr_entry *addr;
4449 	union sctp_addr temp;
4450 	int cnt = 0;
4451 	int addrlen;
4452 
4453 	rcu_read_lock();
4454 	list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
4455 		if (!addr->valid)
4456 			continue;
4457 
4458 		if ((PF_INET == sk->sk_family) &&
4459 		    (AF_INET6 == addr->a.sa.sa_family))
4460 			continue;
4461 		if ((PF_INET6 == sk->sk_family) &&
4462 		    inet_v6_ipv6only(sk) &&
4463 		    (AF_INET == addr->a.sa.sa_family))
4464 			continue;
4465 		memcpy(&temp, &addr->a, sizeof(temp));
4466 		if (!temp.v4.sin_port)
4467 			temp.v4.sin_port = htons(port);
4468 
4469 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4470 								&temp);
4471 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4472 		if (space_left < addrlen) {
4473 			cnt =  -ENOMEM;
4474 			break;
4475 		}
4476 		memcpy(to, &temp, addrlen);
4477 
4478 		to += addrlen;
4479 		cnt ++;
4480 		space_left -= addrlen;
4481 		*bytes_copied += addrlen;
4482 	}
4483 	rcu_read_unlock();
4484 
4485 	return cnt;
4486 }
4487 
4488 
4489 static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
4490 				       char __user *optval, int __user *optlen)
4491 {
4492 	struct sctp_bind_addr *bp;
4493 	struct sctp_association *asoc;
4494 	int cnt = 0;
4495 	struct sctp_getaddrs getaddrs;
4496 	struct sctp_sockaddr_entry *addr;
4497 	void __user *to;
4498 	union sctp_addr temp;
4499 	struct sctp_sock *sp = sctp_sk(sk);
4500 	int addrlen;
4501 	int err = 0;
4502 	size_t space_left;
4503 	int bytes_copied = 0;
4504 	void *addrs;
4505 	void *buf;
4506 
4507 	if (len < sizeof(struct sctp_getaddrs))
4508 		return -EINVAL;
4509 
4510 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4511 		return -EFAULT;
4512 
4513 	/*
4514 	 *  For UDP-style sockets, id specifies the association to query.
4515 	 *  If the id field is set to the value '0' then the locally bound
4516 	 *  addresses are returned without regard to any particular
4517 	 *  association.
4518 	 */
4519 	if (0 == getaddrs.assoc_id) {
4520 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4521 	} else {
4522 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4523 		if (!asoc)
4524 			return -EINVAL;
4525 		bp = &asoc->base.bind_addr;
4526 	}
4527 
4528 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4529 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4530 
4531 	addrs = kmalloc(space_left, GFP_KERNEL);
4532 	if (!addrs)
4533 		return -ENOMEM;
4534 
4535 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4536 	 * addresses from the global local address list.
4537 	 */
4538 	if (sctp_list_single_entry(&bp->address_list)) {
4539 		addr = list_entry(bp->address_list.next,
4540 				  struct sctp_sockaddr_entry, list);
4541 		if (sctp_is_any(sk, &addr->a)) {
4542 			cnt = sctp_copy_laddrs(sk, bp->port, addrs,
4543 						space_left, &bytes_copied);
4544 			if (cnt < 0) {
4545 				err = cnt;
4546 				goto out;
4547 			}
4548 			goto copy_getaddrs;
4549 		}
4550 	}
4551 
4552 	buf = addrs;
4553 	/* Protection on the bound address list is not needed since
4554 	 * in the socket option context we hold a socket lock and
4555 	 * thus the bound address list can't change.
4556 	 */
4557 	list_for_each_entry(addr, &bp->address_list, list) {
4558 		memcpy(&temp, &addr->a, sizeof(temp));
4559 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4560 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4561 		if (space_left < addrlen) {
4562 			err =  -ENOMEM; /*fixme: right error?*/
4563 			goto out;
4564 		}
4565 		memcpy(buf, &temp, addrlen);
4566 		buf += addrlen;
4567 		bytes_copied += addrlen;
4568 		cnt ++;
4569 		space_left -= addrlen;
4570 	}
4571 
4572 copy_getaddrs:
4573 	if (copy_to_user(to, addrs, bytes_copied)) {
4574 		err = -EFAULT;
4575 		goto out;
4576 	}
4577 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num)) {
4578 		err = -EFAULT;
4579 		goto out;
4580 	}
4581 	if (put_user(bytes_copied, optlen))
4582 		err = -EFAULT;
4583 out:
4584 	kfree(addrs);
4585 	return err;
4586 }
4587 
4588 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
4589  *
4590  * Requests that the local SCTP stack use the enclosed peer address as
4591  * the association primary.  The enclosed address must be one of the
4592  * association peer's addresses.
4593  */
4594 static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
4595 					char __user *optval, int __user *optlen)
4596 {
4597 	struct sctp_prim prim;
4598 	struct sctp_association *asoc;
4599 	struct sctp_sock *sp = sctp_sk(sk);
4600 
4601 	if (len < sizeof(struct sctp_prim))
4602 		return -EINVAL;
4603 
4604 	len = sizeof(struct sctp_prim);
4605 
4606 	if (copy_from_user(&prim, optval, len))
4607 		return -EFAULT;
4608 
4609 	asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
4610 	if (!asoc)
4611 		return -EINVAL;
4612 
4613 	if (!asoc->peer.primary_path)
4614 		return -ENOTCONN;
4615 
4616 	memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
4617 		asoc->peer.primary_path->af_specific->sockaddr_len);
4618 
4619 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp,
4620 			(union sctp_addr *)&prim.ssp_addr);
4621 
4622 	if (put_user(len, optlen))
4623 		return -EFAULT;
4624 	if (copy_to_user(optval, &prim, len))
4625 		return -EFAULT;
4626 
4627 	return 0;
4628 }
4629 
4630 /*
4631  * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
4632  *
4633  * Requests that the local endpoint set the specified Adaptation Layer
4634  * Indication parameter for all future INIT and INIT-ACK exchanges.
4635  */
4636 static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
4637 				  char __user *optval, int __user *optlen)
4638 {
4639 	struct sctp_setadaptation adaptation;
4640 
4641 	if (len < sizeof(struct sctp_setadaptation))
4642 		return -EINVAL;
4643 
4644 	len = sizeof(struct sctp_setadaptation);
4645 
4646 	adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
4647 
4648 	if (put_user(len, optlen))
4649 		return -EFAULT;
4650 	if (copy_to_user(optval, &adaptation, len))
4651 		return -EFAULT;
4652 
4653 	return 0;
4654 }
4655 
4656 /*
4657  *
4658  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
4659  *
4660  *   Applications that wish to use the sendto() system call may wish to
4661  *   specify a default set of parameters that would normally be supplied
4662  *   through the inclusion of ancillary data.  This socket option allows
4663  *   such an application to set the default sctp_sndrcvinfo structure.
4664 
4665 
4666  *   The application that wishes to use this socket option simply passes
4667  *   in to this call the sctp_sndrcvinfo structure defined in Section
4668  *   5.2.2) The input parameters accepted by this call include
4669  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
4670  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
4671  *   to this call if the caller is using the UDP model.
4672  *
4673  *   For getsockopt, it get the default sctp_sndrcvinfo structure.
4674  */
4675 static int sctp_getsockopt_default_send_param(struct sock *sk,
4676 					int len, char __user *optval,
4677 					int __user *optlen)
4678 {
4679 	struct sctp_sndrcvinfo info;
4680 	struct sctp_association *asoc;
4681 	struct sctp_sock *sp = sctp_sk(sk);
4682 
4683 	if (len < sizeof(struct sctp_sndrcvinfo))
4684 		return -EINVAL;
4685 
4686 	len = sizeof(struct sctp_sndrcvinfo);
4687 
4688 	if (copy_from_user(&info, optval, len))
4689 		return -EFAULT;
4690 
4691 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
4692 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
4693 		return -EINVAL;
4694 
4695 	if (asoc) {
4696 		info.sinfo_stream = asoc->default_stream;
4697 		info.sinfo_flags = asoc->default_flags;
4698 		info.sinfo_ppid = asoc->default_ppid;
4699 		info.sinfo_context = asoc->default_context;
4700 		info.sinfo_timetolive = asoc->default_timetolive;
4701 	} else {
4702 		info.sinfo_stream = sp->default_stream;
4703 		info.sinfo_flags = sp->default_flags;
4704 		info.sinfo_ppid = sp->default_ppid;
4705 		info.sinfo_context = sp->default_context;
4706 		info.sinfo_timetolive = sp->default_timetolive;
4707 	}
4708 
4709 	if (put_user(len, optlen))
4710 		return -EFAULT;
4711 	if (copy_to_user(optval, &info, len))
4712 		return -EFAULT;
4713 
4714 	return 0;
4715 }
4716 
4717 /*
4718  *
4719  * 7.1.5 SCTP_NODELAY
4720  *
4721  * Turn on/off any Nagle-like algorithm.  This means that packets are
4722  * generally sent as soon as possible and no unnecessary delays are
4723  * introduced, at the cost of more packets in the network.  Expects an
4724  * integer boolean flag.
4725  */
4726 
4727 static int sctp_getsockopt_nodelay(struct sock *sk, int len,
4728 				   char __user *optval, int __user *optlen)
4729 {
4730 	int val;
4731 
4732 	if (len < sizeof(int))
4733 		return -EINVAL;
4734 
4735 	len = sizeof(int);
4736 	val = (sctp_sk(sk)->nodelay == 1);
4737 	if (put_user(len, optlen))
4738 		return -EFAULT;
4739 	if (copy_to_user(optval, &val, len))
4740 		return -EFAULT;
4741 	return 0;
4742 }
4743 
4744 /*
4745  *
4746  * 7.1.1 SCTP_RTOINFO
4747  *
4748  * The protocol parameters used to initialize and bound retransmission
4749  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
4750  * and modify these parameters.
4751  * All parameters are time values, in milliseconds.  A value of 0, when
4752  * modifying the parameters, indicates that the current value should not
4753  * be changed.
4754  *
4755  */
4756 static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
4757 				char __user *optval,
4758 				int __user *optlen) {
4759 	struct sctp_rtoinfo rtoinfo;
4760 	struct sctp_association *asoc;
4761 
4762 	if (len < sizeof (struct sctp_rtoinfo))
4763 		return -EINVAL;
4764 
4765 	len = sizeof(struct sctp_rtoinfo);
4766 
4767 	if (copy_from_user(&rtoinfo, optval, len))
4768 		return -EFAULT;
4769 
4770 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
4771 
4772 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
4773 		return -EINVAL;
4774 
4775 	/* Values corresponding to the specific association. */
4776 	if (asoc) {
4777 		rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
4778 		rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
4779 		rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
4780 	} else {
4781 		/* Values corresponding to the endpoint. */
4782 		struct sctp_sock *sp = sctp_sk(sk);
4783 
4784 		rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
4785 		rtoinfo.srto_max = sp->rtoinfo.srto_max;
4786 		rtoinfo.srto_min = sp->rtoinfo.srto_min;
4787 	}
4788 
4789 	if (put_user(len, optlen))
4790 		return -EFAULT;
4791 
4792 	if (copy_to_user(optval, &rtoinfo, len))
4793 		return -EFAULT;
4794 
4795 	return 0;
4796 }
4797 
4798 /*
4799  *
4800  * 7.1.2 SCTP_ASSOCINFO
4801  *
4802  * This option is used to tune the maximum retransmission attempts
4803  * of the association.
4804  * Returns an error if the new association retransmission value is
4805  * greater than the sum of the retransmission value  of the peer.
4806  * See [SCTP] for more information.
4807  *
4808  */
4809 static int sctp_getsockopt_associnfo(struct sock *sk, int len,
4810 				     char __user *optval,
4811 				     int __user *optlen)
4812 {
4813 
4814 	struct sctp_assocparams assocparams;
4815 	struct sctp_association *asoc;
4816 	struct list_head *pos;
4817 	int cnt = 0;
4818 
4819 	if (len < sizeof (struct sctp_assocparams))
4820 		return -EINVAL;
4821 
4822 	len = sizeof(struct sctp_assocparams);
4823 
4824 	if (copy_from_user(&assocparams, optval, len))
4825 		return -EFAULT;
4826 
4827 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
4828 
4829 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
4830 		return -EINVAL;
4831 
4832 	/* Values correspoinding to the specific association */
4833 	if (asoc) {
4834 		assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
4835 		assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
4836 		assocparams.sasoc_local_rwnd = asoc->a_rwnd;
4837 		assocparams.sasoc_cookie_life = (asoc->cookie_life.tv_sec
4838 						* 1000) +
4839 						(asoc->cookie_life.tv_usec
4840 						/ 1000);
4841 
4842 		list_for_each(pos, &asoc->peer.transport_addr_list) {
4843 			cnt ++;
4844 		}
4845 
4846 		assocparams.sasoc_number_peer_destinations = cnt;
4847 	} else {
4848 		/* Values corresponding to the endpoint */
4849 		struct sctp_sock *sp = sctp_sk(sk);
4850 
4851 		assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
4852 		assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
4853 		assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
4854 		assocparams.sasoc_cookie_life =
4855 					sp->assocparams.sasoc_cookie_life;
4856 		assocparams.sasoc_number_peer_destinations =
4857 					sp->assocparams.
4858 					sasoc_number_peer_destinations;
4859 	}
4860 
4861 	if (put_user(len, optlen))
4862 		return -EFAULT;
4863 
4864 	if (copy_to_user(optval, &assocparams, len))
4865 		return -EFAULT;
4866 
4867 	return 0;
4868 }
4869 
4870 /*
4871  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
4872  *
4873  * This socket option is a boolean flag which turns on or off mapped V4
4874  * addresses.  If this option is turned on and the socket is type
4875  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
4876  * If this option is turned off, then no mapping will be done of V4
4877  * addresses and a user will receive both PF_INET6 and PF_INET type
4878  * addresses on the socket.
4879  */
4880 static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
4881 				    char __user *optval, int __user *optlen)
4882 {
4883 	int val;
4884 	struct sctp_sock *sp = sctp_sk(sk);
4885 
4886 	if (len < sizeof(int))
4887 		return -EINVAL;
4888 
4889 	len = sizeof(int);
4890 	val = sp->v4mapped;
4891 	if (put_user(len, optlen))
4892 		return -EFAULT;
4893 	if (copy_to_user(optval, &val, len))
4894 		return -EFAULT;
4895 
4896 	return 0;
4897 }
4898 
4899 /*
4900  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
4901  * (chapter and verse is quoted at sctp_setsockopt_context())
4902  */
4903 static int sctp_getsockopt_context(struct sock *sk, int len,
4904 				   char __user *optval, int __user *optlen)
4905 {
4906 	struct sctp_assoc_value params;
4907 	struct sctp_sock *sp;
4908 	struct sctp_association *asoc;
4909 
4910 	if (len < sizeof(struct sctp_assoc_value))
4911 		return -EINVAL;
4912 
4913 	len = sizeof(struct sctp_assoc_value);
4914 
4915 	if (copy_from_user(&params, optval, len))
4916 		return -EFAULT;
4917 
4918 	sp = sctp_sk(sk);
4919 
4920 	if (params.assoc_id != 0) {
4921 		asoc = sctp_id2assoc(sk, params.assoc_id);
4922 		if (!asoc)
4923 			return -EINVAL;
4924 		params.assoc_value = asoc->default_rcv_context;
4925 	} else {
4926 		params.assoc_value = sp->default_rcv_context;
4927 	}
4928 
4929 	if (put_user(len, optlen))
4930 		return -EFAULT;
4931 	if (copy_to_user(optval, &params, len))
4932 		return -EFAULT;
4933 
4934 	return 0;
4935 }
4936 
4937 /*
4938  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
4939  * This option will get or set the maximum size to put in any outgoing
4940  * SCTP DATA chunk.  If a message is larger than this size it will be
4941  * fragmented by SCTP into the specified size.  Note that the underlying
4942  * SCTP implementation may fragment into smaller sized chunks when the
4943  * PMTU of the underlying association is smaller than the value set by
4944  * the user.  The default value for this option is '0' which indicates
4945  * the user is NOT limiting fragmentation and only the PMTU will effect
4946  * SCTP's choice of DATA chunk size.  Note also that values set larger
4947  * than the maximum size of an IP datagram will effectively let SCTP
4948  * control fragmentation (i.e. the same as setting this option to 0).
4949  *
4950  * The following structure is used to access and modify this parameter:
4951  *
4952  * struct sctp_assoc_value {
4953  *   sctp_assoc_t assoc_id;
4954  *   uint32_t assoc_value;
4955  * };
4956  *
4957  * assoc_id:  This parameter is ignored for one-to-one style sockets.
4958  *    For one-to-many style sockets this parameter indicates which
4959  *    association the user is performing an action upon.  Note that if
4960  *    this field's value is zero then the endpoints default value is
4961  *    changed (effecting future associations only).
4962  * assoc_value:  This parameter specifies the maximum size in bytes.
4963  */
4964 static int sctp_getsockopt_maxseg(struct sock *sk, int len,
4965 				  char __user *optval, int __user *optlen)
4966 {
4967 	struct sctp_assoc_value params;
4968 	struct sctp_association *asoc;
4969 
4970 	if (len == sizeof(int)) {
4971 		pr_warn("Use of int in maxseg socket option deprecated\n");
4972 		pr_warn("Use struct sctp_assoc_value instead\n");
4973 		params.assoc_id = 0;
4974 	} else if (len >= sizeof(struct sctp_assoc_value)) {
4975 		len = sizeof(struct sctp_assoc_value);
4976 		if (copy_from_user(&params, optval, sizeof(params)))
4977 			return -EFAULT;
4978 	} else
4979 		return -EINVAL;
4980 
4981 	asoc = sctp_id2assoc(sk, params.assoc_id);
4982 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
4983 		return -EINVAL;
4984 
4985 	if (asoc)
4986 		params.assoc_value = asoc->frag_point;
4987 	else
4988 		params.assoc_value = sctp_sk(sk)->user_frag;
4989 
4990 	if (put_user(len, optlen))
4991 		return -EFAULT;
4992 	if (len == sizeof(int)) {
4993 		if (copy_to_user(optval, &params.assoc_value, len))
4994 			return -EFAULT;
4995 	} else {
4996 		if (copy_to_user(optval, &params, len))
4997 			return -EFAULT;
4998 	}
4999 
5000 	return 0;
5001 }
5002 
5003 /*
5004  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
5005  * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
5006  */
5007 static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
5008 					       char __user *optval, int __user *optlen)
5009 {
5010 	int val;
5011 
5012 	if (len < sizeof(int))
5013 		return -EINVAL;
5014 
5015 	len = sizeof(int);
5016 
5017 	val = sctp_sk(sk)->frag_interleave;
5018 	if (put_user(len, optlen))
5019 		return -EFAULT;
5020 	if (copy_to_user(optval, &val, len))
5021 		return -EFAULT;
5022 
5023 	return 0;
5024 }
5025 
5026 /*
5027  * 7.1.25.  Set or Get the sctp partial delivery point
5028  * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
5029  */
5030 static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
5031 						  char __user *optval,
5032 						  int __user *optlen)
5033 {
5034 	u32 val;
5035 
5036 	if (len < sizeof(u32))
5037 		return -EINVAL;
5038 
5039 	len = sizeof(u32);
5040 
5041 	val = sctp_sk(sk)->pd_point;
5042 	if (put_user(len, optlen))
5043 		return -EFAULT;
5044 	if (copy_to_user(optval, &val, len))
5045 		return -EFAULT;
5046 
5047 	return 0;
5048 }
5049 
5050 /*
5051  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
5052  * (chapter and verse is quoted at sctp_setsockopt_maxburst())
5053  */
5054 static int sctp_getsockopt_maxburst(struct sock *sk, int len,
5055 				    char __user *optval,
5056 				    int __user *optlen)
5057 {
5058 	struct sctp_assoc_value params;
5059 	struct sctp_sock *sp;
5060 	struct sctp_association *asoc;
5061 
5062 	if (len == sizeof(int)) {
5063 		pr_warn("Use of int in max_burst socket option deprecated\n");
5064 		pr_warn("Use struct sctp_assoc_value instead\n");
5065 		params.assoc_id = 0;
5066 	} else if (len >= sizeof(struct sctp_assoc_value)) {
5067 		len = sizeof(struct sctp_assoc_value);
5068 		if (copy_from_user(&params, optval, len))
5069 			return -EFAULT;
5070 	} else
5071 		return -EINVAL;
5072 
5073 	sp = sctp_sk(sk);
5074 
5075 	if (params.assoc_id != 0) {
5076 		asoc = sctp_id2assoc(sk, params.assoc_id);
5077 		if (!asoc)
5078 			return -EINVAL;
5079 		params.assoc_value = asoc->max_burst;
5080 	} else
5081 		params.assoc_value = sp->max_burst;
5082 
5083 	if (len == sizeof(int)) {
5084 		if (copy_to_user(optval, &params.assoc_value, len))
5085 			return -EFAULT;
5086 	} else {
5087 		if (copy_to_user(optval, &params, len))
5088 			return -EFAULT;
5089 	}
5090 
5091 	return 0;
5092 
5093 }
5094 
5095 static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
5096 				    char __user *optval, int __user *optlen)
5097 {
5098 	struct sctp_hmacalgo  __user *p = (void __user *)optval;
5099 	struct sctp_hmac_algo_param *hmacs;
5100 	__u16 data_len = 0;
5101 	u32 num_idents;
5102 
5103 	if (!sctp_auth_enable)
5104 		return -EACCES;
5105 
5106 	hmacs = sctp_sk(sk)->ep->auth_hmacs_list;
5107 	data_len = ntohs(hmacs->param_hdr.length) - sizeof(sctp_paramhdr_t);
5108 
5109 	if (len < sizeof(struct sctp_hmacalgo) + data_len)
5110 		return -EINVAL;
5111 
5112 	len = sizeof(struct sctp_hmacalgo) + data_len;
5113 	num_idents = data_len / sizeof(u16);
5114 
5115 	if (put_user(len, optlen))
5116 		return -EFAULT;
5117 	if (put_user(num_idents, &p->shmac_num_idents))
5118 		return -EFAULT;
5119 	if (copy_to_user(p->shmac_idents, hmacs->hmac_ids, data_len))
5120 		return -EFAULT;
5121 	return 0;
5122 }
5123 
5124 static int sctp_getsockopt_active_key(struct sock *sk, int len,
5125 				    char __user *optval, int __user *optlen)
5126 {
5127 	struct sctp_authkeyid val;
5128 	struct sctp_association *asoc;
5129 
5130 	if (!sctp_auth_enable)
5131 		return -EACCES;
5132 
5133 	if (len < sizeof(struct sctp_authkeyid))
5134 		return -EINVAL;
5135 	if (copy_from_user(&val, optval, sizeof(struct sctp_authkeyid)))
5136 		return -EFAULT;
5137 
5138 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
5139 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
5140 		return -EINVAL;
5141 
5142 	if (asoc)
5143 		val.scact_keynumber = asoc->active_key_id;
5144 	else
5145 		val.scact_keynumber = sctp_sk(sk)->ep->active_key_id;
5146 
5147 	len = sizeof(struct sctp_authkeyid);
5148 	if (put_user(len, optlen))
5149 		return -EFAULT;
5150 	if (copy_to_user(optval, &val, len))
5151 		return -EFAULT;
5152 
5153 	return 0;
5154 }
5155 
5156 static int sctp_getsockopt_peer_auth_chunks(struct sock *sk, int len,
5157 				    char __user *optval, int __user *optlen)
5158 {
5159 	struct sctp_authchunks __user *p = (void __user *)optval;
5160 	struct sctp_authchunks val;
5161 	struct sctp_association *asoc;
5162 	struct sctp_chunks_param *ch;
5163 	u32    num_chunks = 0;
5164 	char __user *to;
5165 
5166 	if (!sctp_auth_enable)
5167 		return -EACCES;
5168 
5169 	if (len < sizeof(struct sctp_authchunks))
5170 		return -EINVAL;
5171 
5172 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5173 		return -EFAULT;
5174 
5175 	to = p->gauth_chunks;
5176 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5177 	if (!asoc)
5178 		return -EINVAL;
5179 
5180 	ch = asoc->peer.peer_chunks;
5181 	if (!ch)
5182 		goto num;
5183 
5184 	/* See if the user provided enough room for all the data */
5185 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5186 	if (len < num_chunks)
5187 		return -EINVAL;
5188 
5189 	if (copy_to_user(to, ch->chunks, num_chunks))
5190 		return -EFAULT;
5191 num:
5192 	len = sizeof(struct sctp_authchunks) + num_chunks;
5193 	if (put_user(len, optlen)) return -EFAULT;
5194 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
5195 		return -EFAULT;
5196 	return 0;
5197 }
5198 
5199 static int sctp_getsockopt_local_auth_chunks(struct sock *sk, int len,
5200 				    char __user *optval, int __user *optlen)
5201 {
5202 	struct sctp_authchunks __user *p = (void __user *)optval;
5203 	struct sctp_authchunks val;
5204 	struct sctp_association *asoc;
5205 	struct sctp_chunks_param *ch;
5206 	u32    num_chunks = 0;
5207 	char __user *to;
5208 
5209 	if (!sctp_auth_enable)
5210 		return -EACCES;
5211 
5212 	if (len < sizeof(struct sctp_authchunks))
5213 		return -EINVAL;
5214 
5215 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5216 		return -EFAULT;
5217 
5218 	to = p->gauth_chunks;
5219 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5220 	if (!asoc && val.gauth_assoc_id && sctp_style(sk, UDP))
5221 		return -EINVAL;
5222 
5223 	if (asoc)
5224 		ch = (struct sctp_chunks_param*)asoc->c.auth_chunks;
5225 	else
5226 		ch = sctp_sk(sk)->ep->auth_chunk_list;
5227 
5228 	if (!ch)
5229 		goto num;
5230 
5231 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5232 	if (len < sizeof(struct sctp_authchunks) + num_chunks)
5233 		return -EINVAL;
5234 
5235 	if (copy_to_user(to, ch->chunks, num_chunks))
5236 		return -EFAULT;
5237 num:
5238 	len = sizeof(struct sctp_authchunks) + num_chunks;
5239 	if (put_user(len, optlen))
5240 		return -EFAULT;
5241 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
5242 		return -EFAULT;
5243 
5244 	return 0;
5245 }
5246 
5247 /*
5248  * 8.2.5.  Get the Current Number of Associations (SCTP_GET_ASSOC_NUMBER)
5249  * This option gets the current number of associations that are attached
5250  * to a one-to-many style socket.  The option value is an uint32_t.
5251  */
5252 static int sctp_getsockopt_assoc_number(struct sock *sk, int len,
5253 				    char __user *optval, int __user *optlen)
5254 {
5255 	struct sctp_sock *sp = sctp_sk(sk);
5256 	struct sctp_association *asoc;
5257 	u32 val = 0;
5258 
5259 	if (sctp_style(sk, TCP))
5260 		return -EOPNOTSUPP;
5261 
5262 	if (len < sizeof(u32))
5263 		return -EINVAL;
5264 
5265 	len = sizeof(u32);
5266 
5267 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
5268 		val++;
5269 	}
5270 
5271 	if (put_user(len, optlen))
5272 		return -EFAULT;
5273 	if (copy_to_user(optval, &val, len))
5274 		return -EFAULT;
5275 
5276 	return 0;
5277 }
5278 
5279 /*
5280  * 8.2.6. Get the Current Identifiers of Associations
5281  *        (SCTP_GET_ASSOC_ID_LIST)
5282  *
5283  * This option gets the current list of SCTP association identifiers of
5284  * the SCTP associations handled by a one-to-many style socket.
5285  */
5286 static int sctp_getsockopt_assoc_ids(struct sock *sk, int len,
5287 				    char __user *optval, int __user *optlen)
5288 {
5289 	struct sctp_sock *sp = sctp_sk(sk);
5290 	struct sctp_association *asoc;
5291 	struct sctp_assoc_ids *ids;
5292 	u32 num = 0;
5293 
5294 	if (sctp_style(sk, TCP))
5295 		return -EOPNOTSUPP;
5296 
5297 	if (len < sizeof(struct sctp_assoc_ids))
5298 		return -EINVAL;
5299 
5300 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
5301 		num++;
5302 	}
5303 
5304 	if (len < sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num)
5305 		return -EINVAL;
5306 
5307 	len = sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num;
5308 
5309 	ids = kmalloc(len, GFP_KERNEL);
5310 	if (unlikely(!ids))
5311 		return -ENOMEM;
5312 
5313 	ids->gaids_number_of_ids = num;
5314 	num = 0;
5315 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
5316 		ids->gaids_assoc_id[num++] = asoc->assoc_id;
5317 	}
5318 
5319 	if (put_user(len, optlen) || copy_to_user(optval, ids, len)) {
5320 		kfree(ids);
5321 		return -EFAULT;
5322 	}
5323 
5324 	kfree(ids);
5325 	return 0;
5326 }
5327 
5328 SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
5329 				char __user *optval, int __user *optlen)
5330 {
5331 	int retval = 0;
5332 	int len;
5333 
5334 	SCTP_DEBUG_PRINTK("sctp_getsockopt(sk: %p... optname: %d)\n",
5335 			  sk, optname);
5336 
5337 	/* I can hardly begin to describe how wrong this is.  This is
5338 	 * so broken as to be worse than useless.  The API draft
5339 	 * REALLY is NOT helpful here...  I am not convinced that the
5340 	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
5341 	 * are at all well-founded.
5342 	 */
5343 	if (level != SOL_SCTP) {
5344 		struct sctp_af *af = sctp_sk(sk)->pf->af;
5345 
5346 		retval = af->getsockopt(sk, level, optname, optval, optlen);
5347 		return retval;
5348 	}
5349 
5350 	if (get_user(len, optlen))
5351 		return -EFAULT;
5352 
5353 	sctp_lock_sock(sk);
5354 
5355 	switch (optname) {
5356 	case SCTP_STATUS:
5357 		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
5358 		break;
5359 	case SCTP_DISABLE_FRAGMENTS:
5360 		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
5361 							   optlen);
5362 		break;
5363 	case SCTP_EVENTS:
5364 		retval = sctp_getsockopt_events(sk, len, optval, optlen);
5365 		break;
5366 	case SCTP_AUTOCLOSE:
5367 		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
5368 		break;
5369 	case SCTP_SOCKOPT_PEELOFF:
5370 		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
5371 		break;
5372 	case SCTP_PEER_ADDR_PARAMS:
5373 		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
5374 							  optlen);
5375 		break;
5376 	case SCTP_DELAYED_SACK:
5377 		retval = sctp_getsockopt_delayed_ack(sk, len, optval,
5378 							  optlen);
5379 		break;
5380 	case SCTP_INITMSG:
5381 		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
5382 		break;
5383 	case SCTP_GET_PEER_ADDRS:
5384 		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
5385 						    optlen);
5386 		break;
5387 	case SCTP_GET_LOCAL_ADDRS:
5388 		retval = sctp_getsockopt_local_addrs(sk, len, optval,
5389 						     optlen);
5390 		break;
5391 	case SCTP_SOCKOPT_CONNECTX3:
5392 		retval = sctp_getsockopt_connectx3(sk, len, optval, optlen);
5393 		break;
5394 	case SCTP_DEFAULT_SEND_PARAM:
5395 		retval = sctp_getsockopt_default_send_param(sk, len,
5396 							    optval, optlen);
5397 		break;
5398 	case SCTP_PRIMARY_ADDR:
5399 		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
5400 		break;
5401 	case SCTP_NODELAY:
5402 		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
5403 		break;
5404 	case SCTP_RTOINFO:
5405 		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
5406 		break;
5407 	case SCTP_ASSOCINFO:
5408 		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
5409 		break;
5410 	case SCTP_I_WANT_MAPPED_V4_ADDR:
5411 		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
5412 		break;
5413 	case SCTP_MAXSEG:
5414 		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
5415 		break;
5416 	case SCTP_GET_PEER_ADDR_INFO:
5417 		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
5418 							optlen);
5419 		break;
5420 	case SCTP_ADAPTATION_LAYER:
5421 		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
5422 							optlen);
5423 		break;
5424 	case SCTP_CONTEXT:
5425 		retval = sctp_getsockopt_context(sk, len, optval, optlen);
5426 		break;
5427 	case SCTP_FRAGMENT_INTERLEAVE:
5428 		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
5429 							     optlen);
5430 		break;
5431 	case SCTP_PARTIAL_DELIVERY_POINT:
5432 		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
5433 								optlen);
5434 		break;
5435 	case SCTP_MAX_BURST:
5436 		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
5437 		break;
5438 	case SCTP_AUTH_KEY:
5439 	case SCTP_AUTH_CHUNK:
5440 	case SCTP_AUTH_DELETE_KEY:
5441 		retval = -EOPNOTSUPP;
5442 		break;
5443 	case SCTP_HMAC_IDENT:
5444 		retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
5445 		break;
5446 	case SCTP_AUTH_ACTIVE_KEY:
5447 		retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
5448 		break;
5449 	case SCTP_PEER_AUTH_CHUNKS:
5450 		retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
5451 							optlen);
5452 		break;
5453 	case SCTP_LOCAL_AUTH_CHUNKS:
5454 		retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
5455 							optlen);
5456 		break;
5457 	case SCTP_GET_ASSOC_NUMBER:
5458 		retval = sctp_getsockopt_assoc_number(sk, len, optval, optlen);
5459 		break;
5460 	case SCTP_GET_ASSOC_ID_LIST:
5461 		retval = sctp_getsockopt_assoc_ids(sk, len, optval, optlen);
5462 		break;
5463 	default:
5464 		retval = -ENOPROTOOPT;
5465 		break;
5466 	}
5467 
5468 	sctp_release_sock(sk);
5469 	return retval;
5470 }
5471 
5472 static void sctp_hash(struct sock *sk)
5473 {
5474 	/* STUB */
5475 }
5476 
5477 static void sctp_unhash(struct sock *sk)
5478 {
5479 	/* STUB */
5480 }
5481 
5482 /* Check if port is acceptable.  Possibly find first available port.
5483  *
5484  * The port hash table (contained in the 'global' SCTP protocol storage
5485  * returned by struct sctp_protocol *sctp_get_protocol()). The hash
5486  * table is an array of 4096 lists (sctp_bind_hashbucket). Each
5487  * list (the list number is the port number hashed out, so as you
5488  * would expect from a hash function, all the ports in a given list have
5489  * such a number that hashes out to the same list number; you were
5490  * expecting that, right?); so each list has a set of ports, with a
5491  * link to the socket (struct sock) that uses it, the port number and
5492  * a fastreuse flag (FIXME: NPI ipg).
5493  */
5494 static struct sctp_bind_bucket *sctp_bucket_create(
5495 	struct sctp_bind_hashbucket *head, unsigned short snum);
5496 
5497 static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
5498 {
5499 	struct sctp_bind_hashbucket *head; /* hash list */
5500 	struct sctp_bind_bucket *pp; /* hash list port iterator */
5501 	struct hlist_node *node;
5502 	unsigned short snum;
5503 	int ret;
5504 
5505 	snum = ntohs(addr->v4.sin_port);
5506 
5507 	SCTP_DEBUG_PRINTK("sctp_get_port() begins, snum=%d\n", snum);
5508 	sctp_local_bh_disable();
5509 
5510 	if (snum == 0) {
5511 		/* Search for an available port. */
5512 		int low, high, remaining, index;
5513 		unsigned int rover;
5514 
5515 		inet_get_local_port_range(&low, &high);
5516 		remaining = (high - low) + 1;
5517 		rover = net_random() % remaining + low;
5518 
5519 		do {
5520 			rover++;
5521 			if ((rover < low) || (rover > high))
5522 				rover = low;
5523 			if (inet_is_reserved_local_port(rover))
5524 				continue;
5525 			index = sctp_phashfn(rover);
5526 			head = &sctp_port_hashtable[index];
5527 			sctp_spin_lock(&head->lock);
5528 			sctp_for_each_hentry(pp, node, &head->chain)
5529 				if (pp->port == rover)
5530 					goto next;
5531 			break;
5532 		next:
5533 			sctp_spin_unlock(&head->lock);
5534 		} while (--remaining > 0);
5535 
5536 		/* Exhausted local port range during search? */
5537 		ret = 1;
5538 		if (remaining <= 0)
5539 			goto fail;
5540 
5541 		/* OK, here is the one we will use.  HEAD (the port
5542 		 * hash table list entry) is non-NULL and we hold it's
5543 		 * mutex.
5544 		 */
5545 		snum = rover;
5546 	} else {
5547 		/* We are given an specific port number; we verify
5548 		 * that it is not being used. If it is used, we will
5549 		 * exahust the search in the hash list corresponding
5550 		 * to the port number (snum) - we detect that with the
5551 		 * port iterator, pp being NULL.
5552 		 */
5553 		head = &sctp_port_hashtable[sctp_phashfn(snum)];
5554 		sctp_spin_lock(&head->lock);
5555 		sctp_for_each_hentry(pp, node, &head->chain) {
5556 			if (pp->port == snum)
5557 				goto pp_found;
5558 		}
5559 	}
5560 	pp = NULL;
5561 	goto pp_not_found;
5562 pp_found:
5563 	if (!hlist_empty(&pp->owner)) {
5564 		/* We had a port hash table hit - there is an
5565 		 * available port (pp != NULL) and it is being
5566 		 * used by other socket (pp->owner not empty); that other
5567 		 * socket is going to be sk2.
5568 		 */
5569 		int reuse = sk->sk_reuse;
5570 		struct sock *sk2;
5571 
5572 		SCTP_DEBUG_PRINTK("sctp_get_port() found a possible match\n");
5573 		if (pp->fastreuse && sk->sk_reuse &&
5574 			sk->sk_state != SCTP_SS_LISTENING)
5575 			goto success;
5576 
5577 		/* Run through the list of sockets bound to the port
5578 		 * (pp->port) [via the pointers bind_next and
5579 		 * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
5580 		 * we get the endpoint they describe and run through
5581 		 * the endpoint's list of IP (v4 or v6) addresses,
5582 		 * comparing each of the addresses with the address of
5583 		 * the socket sk. If we find a match, then that means
5584 		 * that this port/socket (sk) combination are already
5585 		 * in an endpoint.
5586 		 */
5587 		sk_for_each_bound(sk2, node, &pp->owner) {
5588 			struct sctp_endpoint *ep2;
5589 			ep2 = sctp_sk(sk2)->ep;
5590 
5591 			if (sk == sk2 ||
5592 			    (reuse && sk2->sk_reuse &&
5593 			     sk2->sk_state != SCTP_SS_LISTENING))
5594 				continue;
5595 
5596 			if (sctp_bind_addr_conflict(&ep2->base.bind_addr, addr,
5597 						 sctp_sk(sk2), sctp_sk(sk))) {
5598 				ret = (long)sk2;
5599 				goto fail_unlock;
5600 			}
5601 		}
5602 		SCTP_DEBUG_PRINTK("sctp_get_port(): Found a match\n");
5603 	}
5604 pp_not_found:
5605 	/* If there was a hash table miss, create a new port.  */
5606 	ret = 1;
5607 	if (!pp && !(pp = sctp_bucket_create(head, snum)))
5608 		goto fail_unlock;
5609 
5610 	/* In either case (hit or miss), make sure fastreuse is 1 only
5611 	 * if sk->sk_reuse is too (that is, if the caller requested
5612 	 * SO_REUSEADDR on this socket -sk-).
5613 	 */
5614 	if (hlist_empty(&pp->owner)) {
5615 		if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
5616 			pp->fastreuse = 1;
5617 		else
5618 			pp->fastreuse = 0;
5619 	} else if (pp->fastreuse &&
5620 		(!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
5621 		pp->fastreuse = 0;
5622 
5623 	/* We are set, so fill up all the data in the hash table
5624 	 * entry, tie the socket list information with the rest of the
5625 	 * sockets FIXME: Blurry, NPI (ipg).
5626 	 */
5627 success:
5628 	if (!sctp_sk(sk)->bind_hash) {
5629 		inet_sk(sk)->inet_num = snum;
5630 		sk_add_bind_node(sk, &pp->owner);
5631 		sctp_sk(sk)->bind_hash = pp;
5632 	}
5633 	ret = 0;
5634 
5635 fail_unlock:
5636 	sctp_spin_unlock(&head->lock);
5637 
5638 fail:
5639 	sctp_local_bh_enable();
5640 	return ret;
5641 }
5642 
5643 /* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
5644  * port is requested.
5645  */
5646 static int sctp_get_port(struct sock *sk, unsigned short snum)
5647 {
5648 	long ret;
5649 	union sctp_addr addr;
5650 	struct sctp_af *af = sctp_sk(sk)->pf->af;
5651 
5652 	/* Set up a dummy address struct from the sk. */
5653 	af->from_sk(&addr, sk);
5654 	addr.v4.sin_port = htons(snum);
5655 
5656 	/* Note: sk->sk_num gets filled in if ephemeral port request. */
5657 	ret = sctp_get_port_local(sk, &addr);
5658 
5659 	return ret ? 1 : 0;
5660 }
5661 
5662 /*
5663  *  Move a socket to LISTENING state.
5664  */
5665 SCTP_STATIC int sctp_listen_start(struct sock *sk, int backlog)
5666 {
5667 	struct sctp_sock *sp = sctp_sk(sk);
5668 	struct sctp_endpoint *ep = sp->ep;
5669 	struct crypto_hash *tfm = NULL;
5670 
5671 	/* Allocate HMAC for generating cookie. */
5672 	if (!sctp_sk(sk)->hmac && sctp_hmac_alg) {
5673 		tfm = crypto_alloc_hash(sctp_hmac_alg, 0, CRYPTO_ALG_ASYNC);
5674 		if (IS_ERR(tfm)) {
5675 			if (net_ratelimit()) {
5676 				pr_info("failed to load transform for %s: %ld\n",
5677 					sctp_hmac_alg, PTR_ERR(tfm));
5678 			}
5679 			return -ENOSYS;
5680 		}
5681 		sctp_sk(sk)->hmac = tfm;
5682 	}
5683 
5684 	/*
5685 	 * If a bind() or sctp_bindx() is not called prior to a listen()
5686 	 * call that allows new associations to be accepted, the system
5687 	 * picks an ephemeral port and will choose an address set equivalent
5688 	 * to binding with a wildcard address.
5689 	 *
5690 	 * This is not currently spelled out in the SCTP sockets
5691 	 * extensions draft, but follows the practice as seen in TCP
5692 	 * sockets.
5693 	 *
5694 	 */
5695 	sk->sk_state = SCTP_SS_LISTENING;
5696 	if (!ep->base.bind_addr.port) {
5697 		if (sctp_autobind(sk))
5698 			return -EAGAIN;
5699 	} else {
5700 		if (sctp_get_port(sk, inet_sk(sk)->inet_num)) {
5701 			sk->sk_state = SCTP_SS_CLOSED;
5702 			return -EADDRINUSE;
5703 		}
5704 	}
5705 
5706 	sk->sk_max_ack_backlog = backlog;
5707 	sctp_hash_endpoint(ep);
5708 	return 0;
5709 }
5710 
5711 /*
5712  * 4.1.3 / 5.1.3 listen()
5713  *
5714  *   By default, new associations are not accepted for UDP style sockets.
5715  *   An application uses listen() to mark a socket as being able to
5716  *   accept new associations.
5717  *
5718  *   On TCP style sockets, applications use listen() to ready the SCTP
5719  *   endpoint for accepting inbound associations.
5720  *
5721  *   On both types of endpoints a backlog of '0' disables listening.
5722  *
5723  *  Move a socket to LISTENING state.
5724  */
5725 int sctp_inet_listen(struct socket *sock, int backlog)
5726 {
5727 	struct sock *sk = sock->sk;
5728 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5729 	int err = -EINVAL;
5730 
5731 	if (unlikely(backlog < 0))
5732 		return err;
5733 
5734 	sctp_lock_sock(sk);
5735 
5736 	/* Peeled-off sockets are not allowed to listen().  */
5737 	if (sctp_style(sk, UDP_HIGH_BANDWIDTH))
5738 		goto out;
5739 
5740 	if (sock->state != SS_UNCONNECTED)
5741 		goto out;
5742 
5743 	/* If backlog is zero, disable listening. */
5744 	if (!backlog) {
5745 		if (sctp_sstate(sk, CLOSED))
5746 			goto out;
5747 
5748 		err = 0;
5749 		sctp_unhash_endpoint(ep);
5750 		sk->sk_state = SCTP_SS_CLOSED;
5751 		if (sk->sk_reuse)
5752 			sctp_sk(sk)->bind_hash->fastreuse = 1;
5753 		goto out;
5754 	}
5755 
5756 	/* If we are already listening, just update the backlog */
5757 	if (sctp_sstate(sk, LISTENING))
5758 		sk->sk_max_ack_backlog = backlog;
5759 	else {
5760 		err = sctp_listen_start(sk, backlog);
5761 		if (err)
5762 			goto out;
5763 	}
5764 
5765 	err = 0;
5766 out:
5767 	sctp_release_sock(sk);
5768 	return err;
5769 }
5770 
5771 /*
5772  * This function is done by modeling the current datagram_poll() and the
5773  * tcp_poll().  Note that, based on these implementations, we don't
5774  * lock the socket in this function, even though it seems that,
5775  * ideally, locking or some other mechanisms can be used to ensure
5776  * the integrity of the counters (sndbuf and wmem_alloc) used
5777  * in this place.  We assume that we don't need locks either until proven
5778  * otherwise.
5779  *
5780  * Another thing to note is that we include the Async I/O support
5781  * here, again, by modeling the current TCP/UDP code.  We don't have
5782  * a good way to test with it yet.
5783  */
5784 unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
5785 {
5786 	struct sock *sk = sock->sk;
5787 	struct sctp_sock *sp = sctp_sk(sk);
5788 	unsigned int mask;
5789 
5790 	poll_wait(file, sk_sleep(sk), wait);
5791 
5792 	/* A TCP-style listening socket becomes readable when the accept queue
5793 	 * is not empty.
5794 	 */
5795 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
5796 		return (!list_empty(&sp->ep->asocs)) ?
5797 			(POLLIN | POLLRDNORM) : 0;
5798 
5799 	mask = 0;
5800 
5801 	/* Is there any exceptional events?  */
5802 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
5803 		mask |= POLLERR;
5804 	if (sk->sk_shutdown & RCV_SHUTDOWN)
5805 		mask |= POLLRDHUP | POLLIN | POLLRDNORM;
5806 	if (sk->sk_shutdown == SHUTDOWN_MASK)
5807 		mask |= POLLHUP;
5808 
5809 	/* Is it readable?  Reconsider this code with TCP-style support.  */
5810 	if (!skb_queue_empty(&sk->sk_receive_queue))
5811 		mask |= POLLIN | POLLRDNORM;
5812 
5813 	/* The association is either gone or not ready.  */
5814 	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
5815 		return mask;
5816 
5817 	/* Is it writable?  */
5818 	if (sctp_writeable(sk)) {
5819 		mask |= POLLOUT | POLLWRNORM;
5820 	} else {
5821 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
5822 		/*
5823 		 * Since the socket is not locked, the buffer
5824 		 * might be made available after the writeable check and
5825 		 * before the bit is set.  This could cause a lost I/O
5826 		 * signal.  tcp_poll() has a race breaker for this race
5827 		 * condition.  Based on their implementation, we put
5828 		 * in the following code to cover it as well.
5829 		 */
5830 		if (sctp_writeable(sk))
5831 			mask |= POLLOUT | POLLWRNORM;
5832 	}
5833 	return mask;
5834 }
5835 
5836 /********************************************************************
5837  * 2nd Level Abstractions
5838  ********************************************************************/
5839 
5840 static struct sctp_bind_bucket *sctp_bucket_create(
5841 	struct sctp_bind_hashbucket *head, unsigned short snum)
5842 {
5843 	struct sctp_bind_bucket *pp;
5844 
5845 	pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
5846 	if (pp) {
5847 		SCTP_DBG_OBJCNT_INC(bind_bucket);
5848 		pp->port = snum;
5849 		pp->fastreuse = 0;
5850 		INIT_HLIST_HEAD(&pp->owner);
5851 		hlist_add_head(&pp->node, &head->chain);
5852 	}
5853 	return pp;
5854 }
5855 
5856 /* Caller must hold hashbucket lock for this tb with local BH disabled */
5857 static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
5858 {
5859 	if (pp && hlist_empty(&pp->owner)) {
5860 		__hlist_del(&pp->node);
5861 		kmem_cache_free(sctp_bucket_cachep, pp);
5862 		SCTP_DBG_OBJCNT_DEC(bind_bucket);
5863 	}
5864 }
5865 
5866 /* Release this socket's reference to a local port.  */
5867 static inline void __sctp_put_port(struct sock *sk)
5868 {
5869 	struct sctp_bind_hashbucket *head =
5870 		&sctp_port_hashtable[sctp_phashfn(inet_sk(sk)->inet_num)];
5871 	struct sctp_bind_bucket *pp;
5872 
5873 	sctp_spin_lock(&head->lock);
5874 	pp = sctp_sk(sk)->bind_hash;
5875 	__sk_del_bind_node(sk);
5876 	sctp_sk(sk)->bind_hash = NULL;
5877 	inet_sk(sk)->inet_num = 0;
5878 	sctp_bucket_destroy(pp);
5879 	sctp_spin_unlock(&head->lock);
5880 }
5881 
5882 void sctp_put_port(struct sock *sk)
5883 {
5884 	sctp_local_bh_disable();
5885 	__sctp_put_port(sk);
5886 	sctp_local_bh_enable();
5887 }
5888 
5889 /*
5890  * The system picks an ephemeral port and choose an address set equivalent
5891  * to binding with a wildcard address.
5892  * One of those addresses will be the primary address for the association.
5893  * This automatically enables the multihoming capability of SCTP.
5894  */
5895 static int sctp_autobind(struct sock *sk)
5896 {
5897 	union sctp_addr autoaddr;
5898 	struct sctp_af *af;
5899 	__be16 port;
5900 
5901 	/* Initialize a local sockaddr structure to INADDR_ANY. */
5902 	af = sctp_sk(sk)->pf->af;
5903 
5904 	port = htons(inet_sk(sk)->inet_num);
5905 	af->inaddr_any(&autoaddr, port);
5906 
5907 	return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
5908 }
5909 
5910 /* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
5911  *
5912  * From RFC 2292
5913  * 4.2 The cmsghdr Structure *
5914  *
5915  * When ancillary data is sent or received, any number of ancillary data
5916  * objects can be specified by the msg_control and msg_controllen members of
5917  * the msghdr structure, because each object is preceded by
5918  * a cmsghdr structure defining the object's length (the cmsg_len member).
5919  * Historically Berkeley-derived implementations have passed only one object
5920  * at a time, but this API allows multiple objects to be
5921  * passed in a single call to sendmsg() or recvmsg(). The following example
5922  * shows two ancillary data objects in a control buffer.
5923  *
5924  *   |<--------------------------- msg_controllen -------------------------->|
5925  *   |                                                                       |
5926  *
5927  *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
5928  *
5929  *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
5930  *   |                                   |                                   |
5931  *
5932  *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
5933  *
5934  *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
5935  *   |                                |  |                                |  |
5936  *
5937  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5938  *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
5939  *
5940  *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
5941  *
5942  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5943  *    ^
5944  *    |
5945  *
5946  * msg_control
5947  * points here
5948  */
5949 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *msg,
5950 				  sctp_cmsgs_t *cmsgs)
5951 {
5952 	struct cmsghdr *cmsg;
5953 	struct msghdr *my_msg = (struct msghdr *)msg;
5954 
5955 	for (cmsg = CMSG_FIRSTHDR(msg);
5956 	     cmsg != NULL;
5957 	     cmsg = CMSG_NXTHDR(my_msg, cmsg)) {
5958 		if (!CMSG_OK(my_msg, cmsg))
5959 			return -EINVAL;
5960 
5961 		/* Should we parse this header or ignore?  */
5962 		if (cmsg->cmsg_level != IPPROTO_SCTP)
5963 			continue;
5964 
5965 		/* Strictly check lengths following example in SCM code.  */
5966 		switch (cmsg->cmsg_type) {
5967 		case SCTP_INIT:
5968 			/* SCTP Socket API Extension
5969 			 * 5.2.1 SCTP Initiation Structure (SCTP_INIT)
5970 			 *
5971 			 * This cmsghdr structure provides information for
5972 			 * initializing new SCTP associations with sendmsg().
5973 			 * The SCTP_INITMSG socket option uses this same data
5974 			 * structure.  This structure is not used for
5975 			 * recvmsg().
5976 			 *
5977 			 * cmsg_level    cmsg_type      cmsg_data[]
5978 			 * ------------  ------------   ----------------------
5979 			 * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
5980 			 */
5981 			if (cmsg->cmsg_len !=
5982 			    CMSG_LEN(sizeof(struct sctp_initmsg)))
5983 				return -EINVAL;
5984 			cmsgs->init = (struct sctp_initmsg *)CMSG_DATA(cmsg);
5985 			break;
5986 
5987 		case SCTP_SNDRCV:
5988 			/* SCTP Socket API Extension
5989 			 * 5.2.2 SCTP Header Information Structure(SCTP_SNDRCV)
5990 			 *
5991 			 * This cmsghdr structure specifies SCTP options for
5992 			 * sendmsg() and describes SCTP header information
5993 			 * about a received message through recvmsg().
5994 			 *
5995 			 * cmsg_level    cmsg_type      cmsg_data[]
5996 			 * ------------  ------------   ----------------------
5997 			 * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
5998 			 */
5999 			if (cmsg->cmsg_len !=
6000 			    CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
6001 				return -EINVAL;
6002 
6003 			cmsgs->info =
6004 				(struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
6005 
6006 			/* Minimally, validate the sinfo_flags. */
6007 			if (cmsgs->info->sinfo_flags &
6008 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
6009 			      SCTP_ABORT | SCTP_EOF))
6010 				return -EINVAL;
6011 			break;
6012 
6013 		default:
6014 			return -EINVAL;
6015 		}
6016 	}
6017 	return 0;
6018 }
6019 
6020 /*
6021  * Wait for a packet..
6022  * Note: This function is the same function as in core/datagram.c
6023  * with a few modifications to make lksctp work.
6024  */
6025 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p)
6026 {
6027 	int error;
6028 	DEFINE_WAIT(wait);
6029 
6030 	prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
6031 
6032 	/* Socket errors? */
6033 	error = sock_error(sk);
6034 	if (error)
6035 		goto out;
6036 
6037 	if (!skb_queue_empty(&sk->sk_receive_queue))
6038 		goto ready;
6039 
6040 	/* Socket shut down?  */
6041 	if (sk->sk_shutdown & RCV_SHUTDOWN)
6042 		goto out;
6043 
6044 	/* Sequenced packets can come disconnected.  If so we report the
6045 	 * problem.
6046 	 */
6047 	error = -ENOTCONN;
6048 
6049 	/* Is there a good reason to think that we may receive some data?  */
6050 	if (list_empty(&sctp_sk(sk)->ep->asocs) && !sctp_sstate(sk, LISTENING))
6051 		goto out;
6052 
6053 	/* Handle signals.  */
6054 	if (signal_pending(current))
6055 		goto interrupted;
6056 
6057 	/* Let another process have a go.  Since we are going to sleep
6058 	 * anyway.  Note: This may cause odd behaviors if the message
6059 	 * does not fit in the user's buffer, but this seems to be the
6060 	 * only way to honor MSG_DONTWAIT realistically.
6061 	 */
6062 	sctp_release_sock(sk);
6063 	*timeo_p = schedule_timeout(*timeo_p);
6064 	sctp_lock_sock(sk);
6065 
6066 ready:
6067 	finish_wait(sk_sleep(sk), &wait);
6068 	return 0;
6069 
6070 interrupted:
6071 	error = sock_intr_errno(*timeo_p);
6072 
6073 out:
6074 	finish_wait(sk_sleep(sk), &wait);
6075 	*err = error;
6076 	return error;
6077 }
6078 
6079 /* Receive a datagram.
6080  * Note: This is pretty much the same routine as in core/datagram.c
6081  * with a few changes to make lksctp work.
6082  */
6083 static struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
6084 					      int noblock, int *err)
6085 {
6086 	int error;
6087 	struct sk_buff *skb;
6088 	long timeo;
6089 
6090 	timeo = sock_rcvtimeo(sk, noblock);
6091 
6092 	SCTP_DEBUG_PRINTK("Timeout: timeo: %ld, MAX: %ld.\n",
6093 			  timeo, MAX_SCHEDULE_TIMEOUT);
6094 
6095 	do {
6096 		/* Again only user level code calls this function,
6097 		 * so nothing interrupt level
6098 		 * will suddenly eat the receive_queue.
6099 		 *
6100 		 *  Look at current nfs client by the way...
6101 		 *  However, this function was correct in any case. 8)
6102 		 */
6103 		if (flags & MSG_PEEK) {
6104 			spin_lock_bh(&sk->sk_receive_queue.lock);
6105 			skb = skb_peek(&sk->sk_receive_queue);
6106 			if (skb)
6107 				atomic_inc(&skb->users);
6108 			spin_unlock_bh(&sk->sk_receive_queue.lock);
6109 		} else {
6110 			skb = skb_dequeue(&sk->sk_receive_queue);
6111 		}
6112 
6113 		if (skb)
6114 			return skb;
6115 
6116 		/* Caller is allowed not to check sk->sk_err before calling. */
6117 		error = sock_error(sk);
6118 		if (error)
6119 			goto no_packet;
6120 
6121 		if (sk->sk_shutdown & RCV_SHUTDOWN)
6122 			break;
6123 
6124 		/* User doesn't want to wait.  */
6125 		error = -EAGAIN;
6126 		if (!timeo)
6127 			goto no_packet;
6128 	} while (sctp_wait_for_packet(sk, err, &timeo) == 0);
6129 
6130 	return NULL;
6131 
6132 no_packet:
6133 	*err = error;
6134 	return NULL;
6135 }
6136 
6137 /* If sndbuf has changed, wake up per association sndbuf waiters.  */
6138 static void __sctp_write_space(struct sctp_association *asoc)
6139 {
6140 	struct sock *sk = asoc->base.sk;
6141 	struct socket *sock = sk->sk_socket;
6142 
6143 	if ((sctp_wspace(asoc) > 0) && sock) {
6144 		if (waitqueue_active(&asoc->wait))
6145 			wake_up_interruptible(&asoc->wait);
6146 
6147 		if (sctp_writeable(sk)) {
6148 			wait_queue_head_t *wq = sk_sleep(sk);
6149 
6150 			if (wq && waitqueue_active(wq))
6151 				wake_up_interruptible(wq);
6152 
6153 			/* Note that we try to include the Async I/O support
6154 			 * here by modeling from the current TCP/UDP code.
6155 			 * We have not tested with it yet.
6156 			 */
6157 			if (!(sk->sk_shutdown & SEND_SHUTDOWN))
6158 				sock_wake_async(sock,
6159 						SOCK_WAKE_SPACE, POLL_OUT);
6160 		}
6161 	}
6162 }
6163 
6164 /* Do accounting for the sndbuf space.
6165  * Decrement the used sndbuf space of the corresponding association by the
6166  * data size which was just transmitted(freed).
6167  */
6168 static void sctp_wfree(struct sk_buff *skb)
6169 {
6170 	struct sctp_association *asoc;
6171 	struct sctp_chunk *chunk;
6172 	struct sock *sk;
6173 
6174 	/* Get the saved chunk pointer.  */
6175 	chunk = *((struct sctp_chunk **)(skb->cb));
6176 	asoc = chunk->asoc;
6177 	sk = asoc->base.sk;
6178 	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
6179 				sizeof(struct sk_buff) +
6180 				sizeof(struct sctp_chunk);
6181 
6182 	atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
6183 
6184 	/*
6185 	 * This undoes what is done via sctp_set_owner_w and sk_mem_charge
6186 	 */
6187 	sk->sk_wmem_queued   -= skb->truesize;
6188 	sk_mem_uncharge(sk, skb->truesize);
6189 
6190 	sock_wfree(skb);
6191 	__sctp_write_space(asoc);
6192 
6193 	sctp_association_put(asoc);
6194 }
6195 
6196 /* Do accounting for the receive space on the socket.
6197  * Accounting for the association is done in ulpevent.c
6198  * We set this as a destructor for the cloned data skbs so that
6199  * accounting is done at the correct time.
6200  */
6201 void sctp_sock_rfree(struct sk_buff *skb)
6202 {
6203 	struct sock *sk = skb->sk;
6204 	struct sctp_ulpevent *event = sctp_skb2event(skb);
6205 
6206 	atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
6207 
6208 	/*
6209 	 * Mimic the behavior of sock_rfree
6210 	 */
6211 	sk_mem_uncharge(sk, event->rmem_len);
6212 }
6213 
6214 
6215 /* Helper function to wait for space in the sndbuf.  */
6216 static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
6217 				size_t msg_len)
6218 {
6219 	struct sock *sk = asoc->base.sk;
6220 	int err = 0;
6221 	long current_timeo = *timeo_p;
6222 	DEFINE_WAIT(wait);
6223 
6224 	SCTP_DEBUG_PRINTK("wait_for_sndbuf: asoc=%p, timeo=%ld, msg_len=%zu\n",
6225 			  asoc, (long)(*timeo_p), msg_len);
6226 
6227 	/* Increment the association's refcnt.  */
6228 	sctp_association_hold(asoc);
6229 
6230 	/* Wait on the association specific sndbuf space. */
6231 	for (;;) {
6232 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6233 					  TASK_INTERRUPTIBLE);
6234 		if (!*timeo_p)
6235 			goto do_nonblock;
6236 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6237 		    asoc->base.dead)
6238 			goto do_error;
6239 		if (signal_pending(current))
6240 			goto do_interrupted;
6241 		if (msg_len <= sctp_wspace(asoc))
6242 			break;
6243 
6244 		/* Let another process have a go.  Since we are going
6245 		 * to sleep anyway.
6246 		 */
6247 		sctp_release_sock(sk);
6248 		current_timeo = schedule_timeout(current_timeo);
6249 		BUG_ON(sk != asoc->base.sk);
6250 		sctp_lock_sock(sk);
6251 
6252 		*timeo_p = current_timeo;
6253 	}
6254 
6255 out:
6256 	finish_wait(&asoc->wait, &wait);
6257 
6258 	/* Release the association's refcnt.  */
6259 	sctp_association_put(asoc);
6260 
6261 	return err;
6262 
6263 do_error:
6264 	err = -EPIPE;
6265 	goto out;
6266 
6267 do_interrupted:
6268 	err = sock_intr_errno(*timeo_p);
6269 	goto out;
6270 
6271 do_nonblock:
6272 	err = -EAGAIN;
6273 	goto out;
6274 }
6275 
6276 void sctp_data_ready(struct sock *sk, int len)
6277 {
6278 	struct socket_wq *wq;
6279 
6280 	rcu_read_lock();
6281 	wq = rcu_dereference(sk->sk_wq);
6282 	if (wq_has_sleeper(wq))
6283 		wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
6284 						POLLRDNORM | POLLRDBAND);
6285 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
6286 	rcu_read_unlock();
6287 }
6288 
6289 /* If socket sndbuf has changed, wake up all per association waiters.  */
6290 void sctp_write_space(struct sock *sk)
6291 {
6292 	struct sctp_association *asoc;
6293 
6294 	/* Wake up the tasks in each wait queue.  */
6295 	list_for_each_entry(asoc, &((sctp_sk(sk))->ep->asocs), asocs) {
6296 		__sctp_write_space(asoc);
6297 	}
6298 }
6299 
6300 /* Is there any sndbuf space available on the socket?
6301  *
6302  * Note that sk_wmem_alloc is the sum of the send buffers on all of the
6303  * associations on the same socket.  For a UDP-style socket with
6304  * multiple associations, it is possible for it to be "unwriteable"
6305  * prematurely.  I assume that this is acceptable because
6306  * a premature "unwriteable" is better than an accidental "writeable" which
6307  * would cause an unwanted block under certain circumstances.  For the 1-1
6308  * UDP-style sockets or TCP-style sockets, this code should work.
6309  *  - Daisy
6310  */
6311 static int sctp_writeable(struct sock *sk)
6312 {
6313 	int amt = 0;
6314 
6315 	amt = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
6316 	if (amt < 0)
6317 		amt = 0;
6318 	return amt;
6319 }
6320 
6321 /* Wait for an association to go into ESTABLISHED state. If timeout is 0,
6322  * returns immediately with EINPROGRESS.
6323  */
6324 static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
6325 {
6326 	struct sock *sk = asoc->base.sk;
6327 	int err = 0;
6328 	long current_timeo = *timeo_p;
6329 	DEFINE_WAIT(wait);
6330 
6331 	SCTP_DEBUG_PRINTK("%s: asoc=%p, timeo=%ld\n", __func__, asoc,
6332 			  (long)(*timeo_p));
6333 
6334 	/* Increment the association's refcnt.  */
6335 	sctp_association_hold(asoc);
6336 
6337 	for (;;) {
6338 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6339 					  TASK_INTERRUPTIBLE);
6340 		if (!*timeo_p)
6341 			goto do_nonblock;
6342 		if (sk->sk_shutdown & RCV_SHUTDOWN)
6343 			break;
6344 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6345 		    asoc->base.dead)
6346 			goto do_error;
6347 		if (signal_pending(current))
6348 			goto do_interrupted;
6349 
6350 		if (sctp_state(asoc, ESTABLISHED))
6351 			break;
6352 
6353 		/* Let another process have a go.  Since we are going
6354 		 * to sleep anyway.
6355 		 */
6356 		sctp_release_sock(sk);
6357 		current_timeo = schedule_timeout(current_timeo);
6358 		sctp_lock_sock(sk);
6359 
6360 		*timeo_p = current_timeo;
6361 	}
6362 
6363 out:
6364 	finish_wait(&asoc->wait, &wait);
6365 
6366 	/* Release the association's refcnt.  */
6367 	sctp_association_put(asoc);
6368 
6369 	return err;
6370 
6371 do_error:
6372 	if (asoc->init_err_counter + 1 > asoc->max_init_attempts)
6373 		err = -ETIMEDOUT;
6374 	else
6375 		err = -ECONNREFUSED;
6376 	goto out;
6377 
6378 do_interrupted:
6379 	err = sock_intr_errno(*timeo_p);
6380 	goto out;
6381 
6382 do_nonblock:
6383 	err = -EINPROGRESS;
6384 	goto out;
6385 }
6386 
6387 static int sctp_wait_for_accept(struct sock *sk, long timeo)
6388 {
6389 	struct sctp_endpoint *ep;
6390 	int err = 0;
6391 	DEFINE_WAIT(wait);
6392 
6393 	ep = sctp_sk(sk)->ep;
6394 
6395 
6396 	for (;;) {
6397 		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
6398 					  TASK_INTERRUPTIBLE);
6399 
6400 		if (list_empty(&ep->asocs)) {
6401 			sctp_release_sock(sk);
6402 			timeo = schedule_timeout(timeo);
6403 			sctp_lock_sock(sk);
6404 		}
6405 
6406 		err = -EINVAL;
6407 		if (!sctp_sstate(sk, LISTENING))
6408 			break;
6409 
6410 		err = 0;
6411 		if (!list_empty(&ep->asocs))
6412 			break;
6413 
6414 		err = sock_intr_errno(timeo);
6415 		if (signal_pending(current))
6416 			break;
6417 
6418 		err = -EAGAIN;
6419 		if (!timeo)
6420 			break;
6421 	}
6422 
6423 	finish_wait(sk_sleep(sk), &wait);
6424 
6425 	return err;
6426 }
6427 
6428 static void sctp_wait_for_close(struct sock *sk, long timeout)
6429 {
6430 	DEFINE_WAIT(wait);
6431 
6432 	do {
6433 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
6434 		if (list_empty(&sctp_sk(sk)->ep->asocs))
6435 			break;
6436 		sctp_release_sock(sk);
6437 		timeout = schedule_timeout(timeout);
6438 		sctp_lock_sock(sk);
6439 	} while (!signal_pending(current) && timeout);
6440 
6441 	finish_wait(sk_sleep(sk), &wait);
6442 }
6443 
6444 static void sctp_skb_set_owner_r_frag(struct sk_buff *skb, struct sock *sk)
6445 {
6446 	struct sk_buff *frag;
6447 
6448 	if (!skb->data_len)
6449 		goto done;
6450 
6451 	/* Don't forget the fragments. */
6452 	skb_walk_frags(skb, frag)
6453 		sctp_skb_set_owner_r_frag(frag, sk);
6454 
6455 done:
6456 	sctp_skb_set_owner_r(skb, sk);
6457 }
6458 
6459 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
6460 		    struct sctp_association *asoc)
6461 {
6462 	struct inet_sock *inet = inet_sk(sk);
6463 	struct inet_sock *newinet;
6464 
6465 	newsk->sk_type = sk->sk_type;
6466 	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
6467 	newsk->sk_flags = sk->sk_flags;
6468 	newsk->sk_no_check = sk->sk_no_check;
6469 	newsk->sk_reuse = sk->sk_reuse;
6470 
6471 	newsk->sk_shutdown = sk->sk_shutdown;
6472 	newsk->sk_destruct = inet_sock_destruct;
6473 	newsk->sk_family = sk->sk_family;
6474 	newsk->sk_protocol = IPPROTO_SCTP;
6475 	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
6476 	newsk->sk_sndbuf = sk->sk_sndbuf;
6477 	newsk->sk_rcvbuf = sk->sk_rcvbuf;
6478 	newsk->sk_lingertime = sk->sk_lingertime;
6479 	newsk->sk_rcvtimeo = sk->sk_rcvtimeo;
6480 	newsk->sk_sndtimeo = sk->sk_sndtimeo;
6481 
6482 	newinet = inet_sk(newsk);
6483 
6484 	/* Initialize sk's sport, dport, rcv_saddr and daddr for
6485 	 * getsockname() and getpeername()
6486 	 */
6487 	newinet->inet_sport = inet->inet_sport;
6488 	newinet->inet_saddr = inet->inet_saddr;
6489 	newinet->inet_rcv_saddr = inet->inet_rcv_saddr;
6490 	newinet->inet_dport = htons(asoc->peer.port);
6491 	newinet->pmtudisc = inet->pmtudisc;
6492 	newinet->inet_id = asoc->next_tsn ^ jiffies;
6493 
6494 	newinet->uc_ttl = inet->uc_ttl;
6495 	newinet->mc_loop = 1;
6496 	newinet->mc_ttl = 1;
6497 	newinet->mc_index = 0;
6498 	newinet->mc_list = NULL;
6499 }
6500 
6501 /* Populate the fields of the newsk from the oldsk and migrate the assoc
6502  * and its messages to the newsk.
6503  */
6504 static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
6505 			      struct sctp_association *assoc,
6506 			      sctp_socket_type_t type)
6507 {
6508 	struct sctp_sock *oldsp = sctp_sk(oldsk);
6509 	struct sctp_sock *newsp = sctp_sk(newsk);
6510 	struct sctp_bind_bucket *pp; /* hash list port iterator */
6511 	struct sctp_endpoint *newep = newsp->ep;
6512 	struct sk_buff *skb, *tmp;
6513 	struct sctp_ulpevent *event;
6514 	struct sctp_bind_hashbucket *head;
6515 
6516 	/* Migrate socket buffer sizes and all the socket level options to the
6517 	 * new socket.
6518 	 */
6519 	newsk->sk_sndbuf = oldsk->sk_sndbuf;
6520 	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
6521 	/* Brute force copy old sctp opt. */
6522 	inet_sk_copy_descendant(newsk, oldsk);
6523 
6524 	/* Restore the ep value that was overwritten with the above structure
6525 	 * copy.
6526 	 */
6527 	newsp->ep = newep;
6528 	newsp->hmac = NULL;
6529 
6530 	/* Hook this new socket in to the bind_hash list. */
6531 	head = &sctp_port_hashtable[sctp_phashfn(inet_sk(oldsk)->inet_num)];
6532 	sctp_local_bh_disable();
6533 	sctp_spin_lock(&head->lock);
6534 	pp = sctp_sk(oldsk)->bind_hash;
6535 	sk_add_bind_node(newsk, &pp->owner);
6536 	sctp_sk(newsk)->bind_hash = pp;
6537 	inet_sk(newsk)->inet_num = inet_sk(oldsk)->inet_num;
6538 	sctp_spin_unlock(&head->lock);
6539 	sctp_local_bh_enable();
6540 
6541 	/* Copy the bind_addr list from the original endpoint to the new
6542 	 * endpoint so that we can handle restarts properly
6543 	 */
6544 	sctp_bind_addr_dup(&newsp->ep->base.bind_addr,
6545 				&oldsp->ep->base.bind_addr, GFP_KERNEL);
6546 
6547 	/* Move any messages in the old socket's receive queue that are for the
6548 	 * peeled off association to the new socket's receive queue.
6549 	 */
6550 	sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
6551 		event = sctp_skb2event(skb);
6552 		if (event->asoc == assoc) {
6553 			__skb_unlink(skb, &oldsk->sk_receive_queue);
6554 			__skb_queue_tail(&newsk->sk_receive_queue, skb);
6555 			sctp_skb_set_owner_r_frag(skb, newsk);
6556 		}
6557 	}
6558 
6559 	/* Clean up any messages pending delivery due to partial
6560 	 * delivery.   Three cases:
6561 	 * 1) No partial deliver;  no work.
6562 	 * 2) Peeling off partial delivery; keep pd_lobby in new pd_lobby.
6563 	 * 3) Peeling off non-partial delivery; move pd_lobby to receive_queue.
6564 	 */
6565 	skb_queue_head_init(&newsp->pd_lobby);
6566 	atomic_set(&sctp_sk(newsk)->pd_mode, assoc->ulpq.pd_mode);
6567 
6568 	if (atomic_read(&sctp_sk(oldsk)->pd_mode)) {
6569 		struct sk_buff_head *queue;
6570 
6571 		/* Decide which queue to move pd_lobby skbs to. */
6572 		if (assoc->ulpq.pd_mode) {
6573 			queue = &newsp->pd_lobby;
6574 		} else
6575 			queue = &newsk->sk_receive_queue;
6576 
6577 		/* Walk through the pd_lobby, looking for skbs that
6578 		 * need moved to the new socket.
6579 		 */
6580 		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
6581 			event = sctp_skb2event(skb);
6582 			if (event->asoc == assoc) {
6583 				__skb_unlink(skb, &oldsp->pd_lobby);
6584 				__skb_queue_tail(queue, skb);
6585 				sctp_skb_set_owner_r_frag(skb, newsk);
6586 			}
6587 		}
6588 
6589 		/* Clear up any skbs waiting for the partial
6590 		 * delivery to finish.
6591 		 */
6592 		if (assoc->ulpq.pd_mode)
6593 			sctp_clear_pd(oldsk, NULL);
6594 
6595 	}
6596 
6597 	sctp_skb_for_each(skb, &assoc->ulpq.reasm, tmp)
6598 		sctp_skb_set_owner_r_frag(skb, newsk);
6599 
6600 	sctp_skb_for_each(skb, &assoc->ulpq.lobby, tmp)
6601 		sctp_skb_set_owner_r_frag(skb, newsk);
6602 
6603 	/* Set the type of socket to indicate that it is peeled off from the
6604 	 * original UDP-style socket or created with the accept() call on a
6605 	 * TCP-style socket..
6606 	 */
6607 	newsp->type = type;
6608 
6609 	/* Mark the new socket "in-use" by the user so that any packets
6610 	 * that may arrive on the association after we've moved it are
6611 	 * queued to the backlog.  This prevents a potential race between
6612 	 * backlog processing on the old socket and new-packet processing
6613 	 * on the new socket.
6614 	 *
6615 	 * The caller has just allocated newsk so we can guarantee that other
6616 	 * paths won't try to lock it and then oldsk.
6617 	 */
6618 	lock_sock_nested(newsk, SINGLE_DEPTH_NESTING);
6619 	sctp_assoc_migrate(assoc, newsk);
6620 
6621 	/* If the association on the newsk is already closed before accept()
6622 	 * is called, set RCV_SHUTDOWN flag.
6623 	 */
6624 	if (sctp_state(assoc, CLOSED) && sctp_style(newsk, TCP))
6625 		newsk->sk_shutdown |= RCV_SHUTDOWN;
6626 
6627 	newsk->sk_state = SCTP_SS_ESTABLISHED;
6628 	sctp_release_sock(newsk);
6629 }
6630 
6631 
6632 /* This proto struct describes the ULP interface for SCTP.  */
6633 struct proto sctp_prot = {
6634 	.name        =	"SCTP",
6635 	.owner       =	THIS_MODULE,
6636 	.close       =	sctp_close,
6637 	.connect     =	sctp_connect,
6638 	.disconnect  =	sctp_disconnect,
6639 	.accept      =	sctp_accept,
6640 	.ioctl       =	sctp_ioctl,
6641 	.init        =	sctp_init_sock,
6642 	.destroy     =	sctp_destroy_sock,
6643 	.shutdown    =	sctp_shutdown,
6644 	.setsockopt  =	sctp_setsockopt,
6645 	.getsockopt  =	sctp_getsockopt,
6646 	.sendmsg     =	sctp_sendmsg,
6647 	.recvmsg     =	sctp_recvmsg,
6648 	.bind        =	sctp_bind,
6649 	.backlog_rcv =	sctp_backlog_rcv,
6650 	.hash        =	sctp_hash,
6651 	.unhash      =	sctp_unhash,
6652 	.get_port    =	sctp_get_port,
6653 	.obj_size    =  sizeof(struct sctp_sock),
6654 	.sysctl_mem  =  sysctl_sctp_mem,
6655 	.sysctl_rmem =  sysctl_sctp_rmem,
6656 	.sysctl_wmem =  sysctl_sctp_wmem,
6657 	.memory_pressure = &sctp_memory_pressure,
6658 	.enter_memory_pressure = sctp_enter_memory_pressure,
6659 	.memory_allocated = &sctp_memory_allocated,
6660 	.sockets_allocated = &sctp_sockets_allocated,
6661 };
6662 
6663 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6664 
6665 struct proto sctpv6_prot = {
6666 	.name		= "SCTPv6",
6667 	.owner		= THIS_MODULE,
6668 	.close		= sctp_close,
6669 	.connect	= sctp_connect,
6670 	.disconnect	= sctp_disconnect,
6671 	.accept		= sctp_accept,
6672 	.ioctl		= sctp_ioctl,
6673 	.init		= sctp_init_sock,
6674 	.destroy	= sctp_destroy_sock,
6675 	.shutdown	= sctp_shutdown,
6676 	.setsockopt	= sctp_setsockopt,
6677 	.getsockopt	= sctp_getsockopt,
6678 	.sendmsg	= sctp_sendmsg,
6679 	.recvmsg	= sctp_recvmsg,
6680 	.bind		= sctp_bind,
6681 	.backlog_rcv	= sctp_backlog_rcv,
6682 	.hash		= sctp_hash,
6683 	.unhash		= sctp_unhash,
6684 	.get_port	= sctp_get_port,
6685 	.obj_size	= sizeof(struct sctp6_sock),
6686 	.sysctl_mem	= sysctl_sctp_mem,
6687 	.sysctl_rmem	= sysctl_sctp_rmem,
6688 	.sysctl_wmem	= sysctl_sctp_wmem,
6689 	.memory_pressure = &sctp_memory_pressure,
6690 	.enter_memory_pressure = sctp_enter_memory_pressure,
6691 	.memory_allocated = &sctp_memory_allocated,
6692 	.sockets_allocated = &sctp_sockets_allocated,
6693 };
6694 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
6695