xref: /linux/net/sctp/socket.c (revision dfc349402de8e95f6a42e8341e9ea193b718eee3)
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 #include <linux/types.h>
61 #include <linux/kernel.h>
62 #include <linux/wait.h>
63 #include <linux/time.h>
64 #include <linux/ip.h>
65 #include <linux/capability.h>
66 #include <linux/fcntl.h>
67 #include <linux/poll.h>
68 #include <linux/init.h>
69 #include <linux/crypto.h>
70 
71 #include <net/ip.h>
72 #include <net/icmp.h>
73 #include <net/route.h>
74 #include <net/ipv6.h>
75 #include <net/inet_common.h>
76 
77 #include <linux/socket.h> /* for sa_family_t */
78 #include <net/sock.h>
79 #include <net/sctp/sctp.h>
80 #include <net/sctp/sm.h>
81 
82 /* WARNING:  Please do not remove the SCTP_STATIC attribute to
83  * any of the functions below as they are used to export functions
84  * used by a project regression testsuite.
85  */
86 
87 /* Forward declarations for internal helper functions. */
88 static int sctp_writeable(struct sock *sk);
89 static void sctp_wfree(struct sk_buff *skb);
90 static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p,
91 				size_t msg_len);
92 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p);
93 static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);
94 static int sctp_wait_for_accept(struct sock *sk, long timeo);
95 static void sctp_wait_for_close(struct sock *sk, long timeo);
96 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
97 					union sctp_addr *addr, int len);
98 static int sctp_bindx_add(struct sock *, struct sockaddr *, int);
99 static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);
100 static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);
101 static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);
102 static int sctp_send_asconf(struct sctp_association *asoc,
103 			    struct sctp_chunk *chunk);
104 static int sctp_do_bind(struct sock *, union sctp_addr *, int);
105 static int sctp_autobind(struct sock *sk);
106 static void sctp_sock_migrate(struct sock *, struct sock *,
107 			      struct sctp_association *, sctp_socket_type_t);
108 static char *sctp_hmac_alg = SCTP_COOKIE_HMAC_ALG;
109 
110 extern struct kmem_cache *sctp_bucket_cachep;
111 extern int sysctl_sctp_mem[3];
112 extern int sysctl_sctp_rmem[3];
113 extern int sysctl_sctp_wmem[3];
114 
115 static int sctp_memory_pressure;
116 static atomic_t sctp_memory_allocated;
117 struct percpu_counter sctp_sockets_allocated;
118 
119 static void sctp_enter_memory_pressure(struct sock *sk)
120 {
121 	sctp_memory_pressure = 1;
122 }
123 
124 
125 /* Get the sndbuf space available at the time on the association.  */
126 static inline int sctp_wspace(struct sctp_association *asoc)
127 {
128 	int amt;
129 
130 	if (asoc->ep->sndbuf_policy)
131 		amt = asoc->sndbuf_used;
132 	else
133 		amt = sk_wmem_alloc_get(asoc->base.sk);
134 
135 	if (amt >= asoc->base.sk->sk_sndbuf) {
136 		if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK)
137 			amt = 0;
138 		else {
139 			amt = sk_stream_wspace(asoc->base.sk);
140 			if (amt < 0)
141 				amt = 0;
142 		}
143 	} else {
144 		amt = asoc->base.sk->sk_sndbuf - amt;
145 	}
146 	return amt;
147 }
148 
149 /* Increment the used sndbuf space count of the corresponding association by
150  * the size of the outgoing data chunk.
151  * Also, set the skb destructor for sndbuf accounting later.
152  *
153  * Since it is always 1-1 between chunk and skb, and also a new skb is always
154  * allocated for chunk bundling in sctp_packet_transmit(), we can use the
155  * destructor in the data chunk skb for the purpose of the sndbuf space
156  * tracking.
157  */
158 static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
159 {
160 	struct sctp_association *asoc = chunk->asoc;
161 	struct sock *sk = asoc->base.sk;
162 
163 	/* The sndbuf space is tracked per association.  */
164 	sctp_association_hold(asoc);
165 
166 	skb_set_owner_w(chunk->skb, sk);
167 
168 	chunk->skb->destructor = sctp_wfree;
169 	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
170 	*((struct sctp_chunk **)(chunk->skb->cb)) = chunk;
171 
172 	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
173 				sizeof(struct sk_buff) +
174 				sizeof(struct sctp_chunk);
175 
176 	atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
177 	sk->sk_wmem_queued += chunk->skb->truesize;
178 	sk_mem_charge(sk, chunk->skb->truesize);
179 }
180 
181 /* Verify that this is a valid address. */
182 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
183 				   int len)
184 {
185 	struct sctp_af *af;
186 
187 	/* Verify basic sockaddr. */
188 	af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
189 	if (!af)
190 		return -EINVAL;
191 
192 	/* Is this a valid SCTP address?  */
193 	if (!af->addr_valid(addr, sctp_sk(sk), NULL))
194 		return -EINVAL;
195 
196 	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
197 		return -EINVAL;
198 
199 	return 0;
200 }
201 
202 /* Look up the association by its id.  If this is not a UDP-style
203  * socket, the ID field is always ignored.
204  */
205 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
206 {
207 	struct sctp_association *asoc = NULL;
208 
209 	/* If this is not a UDP-style socket, assoc id should be ignored. */
210 	if (!sctp_style(sk, UDP)) {
211 		/* Return NULL if the socket state is not ESTABLISHED. It
212 		 * could be a TCP-style listening socket or a socket which
213 		 * hasn't yet called connect() to establish an association.
214 		 */
215 		if (!sctp_sstate(sk, ESTABLISHED))
216 			return NULL;
217 
218 		/* Get the first and the only association from the list. */
219 		if (!list_empty(&sctp_sk(sk)->ep->asocs))
220 			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
221 					  struct sctp_association, asocs);
222 		return asoc;
223 	}
224 
225 	/* Otherwise this is a UDP-style socket. */
226 	if (!id || (id == (sctp_assoc_t)-1))
227 		return NULL;
228 
229 	spin_lock_bh(&sctp_assocs_id_lock);
230 	asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
231 	spin_unlock_bh(&sctp_assocs_id_lock);
232 
233 	if (!asoc || (asoc->base.sk != sk) || asoc->base.dead)
234 		return NULL;
235 
236 	return asoc;
237 }
238 
239 /* Look up the transport from an address and an assoc id. If both address and
240  * id are specified, the associations matching the address and the id should be
241  * the same.
242  */
243 static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
244 					      struct sockaddr_storage *addr,
245 					      sctp_assoc_t id)
246 {
247 	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
248 	struct sctp_transport *transport;
249 	union sctp_addr *laddr = (union sctp_addr *)addr;
250 
251 	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
252 					       laddr,
253 					       &transport);
254 
255 	if (!addr_asoc)
256 		return NULL;
257 
258 	id_asoc = sctp_id2assoc(sk, id);
259 	if (id_asoc && (id_asoc != addr_asoc))
260 		return NULL;
261 
262 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
263 						(union sctp_addr *)addr);
264 
265 	return transport;
266 }
267 
268 /* API 3.1.2 bind() - UDP Style Syntax
269  * The syntax of bind() is,
270  *
271  *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
272  *
273  *   sd      - the socket descriptor returned by socket().
274  *   addr    - the address structure (struct sockaddr_in or struct
275  *             sockaddr_in6 [RFC 2553]),
276  *   addr_len - the size of the address structure.
277  */
278 SCTP_STATIC int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
279 {
280 	int retval = 0;
281 
282 	sctp_lock_sock(sk);
283 
284 	SCTP_DEBUG_PRINTK("sctp_bind(sk: %p, addr: %p, addr_len: %d)\n",
285 			  sk, addr, addr_len);
286 
287 	/* Disallow binding twice. */
288 	if (!sctp_sk(sk)->ep->base.bind_addr.port)
289 		retval = sctp_do_bind(sk, (union sctp_addr *)addr,
290 				      addr_len);
291 	else
292 		retval = -EINVAL;
293 
294 	sctp_release_sock(sk);
295 
296 	return retval;
297 }
298 
299 static long sctp_get_port_local(struct sock *, union sctp_addr *);
300 
301 /* Verify this is a valid sockaddr. */
302 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
303 					union sctp_addr *addr, int len)
304 {
305 	struct sctp_af *af;
306 
307 	/* Check minimum size.  */
308 	if (len < sizeof (struct sockaddr))
309 		return NULL;
310 
311 	/* V4 mapped address are really of AF_INET family */
312 	if (addr->sa.sa_family == AF_INET6 &&
313 	    ipv6_addr_v4mapped(&addr->v6.sin6_addr)) {
314 		if (!opt->pf->af_supported(AF_INET, opt))
315 			return NULL;
316 	} else {
317 		/* Does this PF support this AF? */
318 		if (!opt->pf->af_supported(addr->sa.sa_family, opt))
319 			return NULL;
320 	}
321 
322 	/* If we get this far, af is valid. */
323 	af = sctp_get_af_specific(addr->sa.sa_family);
324 
325 	if (len < af->sockaddr_len)
326 		return NULL;
327 
328 	return af;
329 }
330 
331 /* Bind a local address either to an endpoint or to an association.  */
332 SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
333 {
334 	struct sctp_sock *sp = sctp_sk(sk);
335 	struct sctp_endpoint *ep = sp->ep;
336 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
337 	struct sctp_af *af;
338 	unsigned short snum;
339 	int ret = 0;
340 
341 	/* Common sockaddr verification. */
342 	af = sctp_sockaddr_af(sp, addr, len);
343 	if (!af) {
344 		SCTP_DEBUG_PRINTK("sctp_do_bind(sk: %p, newaddr: %p, len: %d) EINVAL\n",
345 				  sk, addr, len);
346 		return -EINVAL;
347 	}
348 
349 	snum = ntohs(addr->v4.sin_port);
350 
351 	SCTP_DEBUG_PRINTK_IPADDR("sctp_do_bind(sk: %p, new addr: ",
352 				 ", port: %d, new port: %d, len: %d)\n",
353 				 sk,
354 				 addr,
355 				 bp->port, snum,
356 				 len);
357 
358 	/* PF specific bind() address verification. */
359 	if (!sp->pf->bind_verify(sp, addr))
360 		return -EADDRNOTAVAIL;
361 
362 	/* We must either be unbound, or bind to the same port.
363 	 * It's OK to allow 0 ports if we are already bound.
364 	 * We'll just inhert an already bound port in this case
365 	 */
366 	if (bp->port) {
367 		if (!snum)
368 			snum = bp->port;
369 		else if (snum != bp->port) {
370 			SCTP_DEBUG_PRINTK("sctp_do_bind:"
371 				  " New port %d does not match existing port "
372 				  "%d.\n", snum, bp->port);
373 			return -EINVAL;
374 		}
375 	}
376 
377 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
378 		return -EACCES;
379 
380 	/* See if the address matches any of the addresses we may have
381 	 * already bound before checking against other endpoints.
382 	 */
383 	if (sctp_bind_addr_match(bp, addr, sp))
384 		return -EINVAL;
385 
386 	/* Make sure we are allowed to bind here.
387 	 * The function sctp_get_port_local() does duplicate address
388 	 * detection.
389 	 */
390 	addr->v4.sin_port = htons(snum);
391 	if ((ret = sctp_get_port_local(sk, addr))) {
392 		return -EADDRINUSE;
393 	}
394 
395 	/* Refresh ephemeral port.  */
396 	if (!bp->port)
397 		bp->port = inet_sk(sk)->num;
398 
399 	/* Add the address to the bind address list.
400 	 * Use GFP_ATOMIC since BHs will be disabled.
401 	 */
402 	ret = sctp_add_bind_addr(bp, addr, SCTP_ADDR_SRC, GFP_ATOMIC);
403 
404 	/* Copy back into socket for getsockname() use. */
405 	if (!ret) {
406 		inet_sk(sk)->sport = htons(inet_sk(sk)->num);
407 		af->to_sk_saddr(addr, sk);
408 	}
409 
410 	return ret;
411 }
412 
413  /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
414  *
415  * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
416  * at any one time.  If a sender, after sending an ASCONF chunk, decides
417  * it needs to transfer another ASCONF Chunk, it MUST wait until the
418  * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
419  * subsequent ASCONF. Note this restriction binds each side, so at any
420  * time two ASCONF may be in-transit on any given association (one sent
421  * from each endpoint).
422  */
423 static int sctp_send_asconf(struct sctp_association *asoc,
424 			    struct sctp_chunk *chunk)
425 {
426 	int		retval = 0;
427 
428 	/* If there is an outstanding ASCONF chunk, queue it for later
429 	 * transmission.
430 	 */
431 	if (asoc->addip_last_asconf) {
432 		list_add_tail(&chunk->list, &asoc->addip_chunk_list);
433 		goto out;
434 	}
435 
436 	/* Hold the chunk until an ASCONF_ACK is received. */
437 	sctp_chunk_hold(chunk);
438 	retval = sctp_primitive_ASCONF(asoc, chunk);
439 	if (retval)
440 		sctp_chunk_free(chunk);
441 	else
442 		asoc->addip_last_asconf = chunk;
443 
444 out:
445 	return retval;
446 }
447 
448 /* Add a list of addresses as bind addresses to local endpoint or
449  * association.
450  *
451  * Basically run through each address specified in the addrs/addrcnt
452  * array/length pair, determine if it is IPv6 or IPv4 and call
453  * sctp_do_bind() on it.
454  *
455  * If any of them fails, then the operation will be reversed and the
456  * ones that were added will be removed.
457  *
458  * Only sctp_setsockopt_bindx() is supposed to call this function.
459  */
460 static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
461 {
462 	int cnt;
463 	int retval = 0;
464 	void *addr_buf;
465 	struct sockaddr *sa_addr;
466 	struct sctp_af *af;
467 
468 	SCTP_DEBUG_PRINTK("sctp_bindx_add (sk: %p, addrs: %p, addrcnt: %d)\n",
469 			  sk, addrs, addrcnt);
470 
471 	addr_buf = addrs;
472 	for (cnt = 0; cnt < addrcnt; cnt++) {
473 		/* The list may contain either IPv4 or IPv6 address;
474 		 * determine the address length for walking thru the list.
475 		 */
476 		sa_addr = (struct sockaddr *)addr_buf;
477 		af = sctp_get_af_specific(sa_addr->sa_family);
478 		if (!af) {
479 			retval = -EINVAL;
480 			goto err_bindx_add;
481 		}
482 
483 		retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
484 				      af->sockaddr_len);
485 
486 		addr_buf += af->sockaddr_len;
487 
488 err_bindx_add:
489 		if (retval < 0) {
490 			/* Failed. Cleanup the ones that have been added */
491 			if (cnt > 0)
492 				sctp_bindx_rem(sk, addrs, cnt);
493 			return retval;
494 		}
495 	}
496 
497 	return retval;
498 }
499 
500 /* Send an ASCONF chunk with Add IP address parameters to all the peers of the
501  * associations that are part of the endpoint indicating that a list of local
502  * addresses are added to the endpoint.
503  *
504  * If any of the addresses is already in the bind address list of the
505  * association, we do not send the chunk for that association.  But it will not
506  * affect other associations.
507  *
508  * Only sctp_setsockopt_bindx() is supposed to call this function.
509  */
510 static int sctp_send_asconf_add_ip(struct sock		*sk,
511 				   struct sockaddr	*addrs,
512 				   int 			addrcnt)
513 {
514 	struct sctp_sock		*sp;
515 	struct sctp_endpoint		*ep;
516 	struct sctp_association		*asoc;
517 	struct sctp_bind_addr		*bp;
518 	struct sctp_chunk		*chunk;
519 	struct sctp_sockaddr_entry	*laddr;
520 	union sctp_addr			*addr;
521 	union sctp_addr			saveaddr;
522 	void				*addr_buf;
523 	struct sctp_af			*af;
524 	struct list_head		*p;
525 	int 				i;
526 	int 				retval = 0;
527 
528 	if (!sctp_addip_enable)
529 		return retval;
530 
531 	sp = sctp_sk(sk);
532 	ep = sp->ep;
533 
534 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
535 			  __func__, sk, addrs, addrcnt);
536 
537 	list_for_each_entry(asoc, &ep->asocs, asocs) {
538 
539 		if (!asoc->peer.asconf_capable)
540 			continue;
541 
542 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
543 			continue;
544 
545 		if (!sctp_state(asoc, ESTABLISHED))
546 			continue;
547 
548 		/* Check if any address in the packed array of addresses is
549 		 * in the bind address list of the association. If so,
550 		 * do not send the asconf chunk to its peer, but continue with
551 		 * other associations.
552 		 */
553 		addr_buf = addrs;
554 		for (i = 0; i < addrcnt; i++) {
555 			addr = (union sctp_addr *)addr_buf;
556 			af = sctp_get_af_specific(addr->v4.sin_family);
557 			if (!af) {
558 				retval = -EINVAL;
559 				goto out;
560 			}
561 
562 			if (sctp_assoc_lookup_laddr(asoc, addr))
563 				break;
564 
565 			addr_buf += af->sockaddr_len;
566 		}
567 		if (i < addrcnt)
568 			continue;
569 
570 		/* Use the first valid address in bind addr list of
571 		 * association as Address Parameter of ASCONF CHUNK.
572 		 */
573 		bp = &asoc->base.bind_addr;
574 		p = bp->address_list.next;
575 		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
576 		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
577 						   addrcnt, SCTP_PARAM_ADD_IP);
578 		if (!chunk) {
579 			retval = -ENOMEM;
580 			goto out;
581 		}
582 
583 		retval = sctp_send_asconf(asoc, chunk);
584 		if (retval)
585 			goto out;
586 
587 		/* Add the new addresses to the bind address list with
588 		 * use_as_src set to 0.
589 		 */
590 		addr_buf = addrs;
591 		for (i = 0; i < addrcnt; i++) {
592 			addr = (union sctp_addr *)addr_buf;
593 			af = sctp_get_af_specific(addr->v4.sin_family);
594 			memcpy(&saveaddr, addr, af->sockaddr_len);
595 			retval = sctp_add_bind_addr(bp, &saveaddr,
596 						    SCTP_ADDR_NEW, GFP_ATOMIC);
597 			addr_buf += af->sockaddr_len;
598 		}
599 	}
600 
601 out:
602 	return retval;
603 }
604 
605 /* Remove a list of addresses from bind addresses list.  Do not remove the
606  * last address.
607  *
608  * Basically run through each address specified in the addrs/addrcnt
609  * array/length pair, determine if it is IPv6 or IPv4 and call
610  * sctp_del_bind() on it.
611  *
612  * If any of them fails, then the operation will be reversed and the
613  * ones that were removed will be added back.
614  *
615  * At least one address has to be left; if only one address is
616  * available, the operation will return -EBUSY.
617  *
618  * Only sctp_setsockopt_bindx() is supposed to call this function.
619  */
620 static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
621 {
622 	struct sctp_sock *sp = sctp_sk(sk);
623 	struct sctp_endpoint *ep = sp->ep;
624 	int cnt;
625 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
626 	int retval = 0;
627 	void *addr_buf;
628 	union sctp_addr *sa_addr;
629 	struct sctp_af *af;
630 
631 	SCTP_DEBUG_PRINTK("sctp_bindx_rem (sk: %p, addrs: %p, addrcnt: %d)\n",
632 			  sk, addrs, addrcnt);
633 
634 	addr_buf = addrs;
635 	for (cnt = 0; cnt < addrcnt; cnt++) {
636 		/* If the bind address list is empty or if there is only one
637 		 * bind address, there is nothing more to be removed (we need
638 		 * at least one address here).
639 		 */
640 		if (list_empty(&bp->address_list) ||
641 		    (sctp_list_single_entry(&bp->address_list))) {
642 			retval = -EBUSY;
643 			goto err_bindx_rem;
644 		}
645 
646 		sa_addr = (union sctp_addr *)addr_buf;
647 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
648 		if (!af) {
649 			retval = -EINVAL;
650 			goto err_bindx_rem;
651 		}
652 
653 		if (!af->addr_valid(sa_addr, sp, NULL)) {
654 			retval = -EADDRNOTAVAIL;
655 			goto err_bindx_rem;
656 		}
657 
658 		if (sa_addr->v4.sin_port != htons(bp->port)) {
659 			retval = -EINVAL;
660 			goto err_bindx_rem;
661 		}
662 
663 		/* FIXME - There is probably a need to check if sk->sk_saddr and
664 		 * sk->sk_rcv_addr are currently set to one of the addresses to
665 		 * be removed. This is something which needs to be looked into
666 		 * when we are fixing the outstanding issues with multi-homing
667 		 * socket routing and failover schemes. Refer to comments in
668 		 * sctp_do_bind(). -daisy
669 		 */
670 		retval = sctp_del_bind_addr(bp, sa_addr);
671 
672 		addr_buf += af->sockaddr_len;
673 err_bindx_rem:
674 		if (retval < 0) {
675 			/* Failed. Add the ones that has been removed back */
676 			if (cnt > 0)
677 				sctp_bindx_add(sk, addrs, cnt);
678 			return retval;
679 		}
680 	}
681 
682 	return retval;
683 }
684 
685 /* Send an ASCONF chunk with Delete IP address parameters to all the peers of
686  * the associations that are part of the endpoint indicating that a list of
687  * local addresses are removed from the endpoint.
688  *
689  * If any of the addresses is already in the bind address list of the
690  * association, we do not send the chunk for that association.  But it will not
691  * affect other associations.
692  *
693  * Only sctp_setsockopt_bindx() is supposed to call this function.
694  */
695 static int sctp_send_asconf_del_ip(struct sock		*sk,
696 				   struct sockaddr	*addrs,
697 				   int			addrcnt)
698 {
699 	struct sctp_sock	*sp;
700 	struct sctp_endpoint	*ep;
701 	struct sctp_association	*asoc;
702 	struct sctp_transport	*transport;
703 	struct sctp_bind_addr	*bp;
704 	struct sctp_chunk	*chunk;
705 	union sctp_addr		*laddr;
706 	void			*addr_buf;
707 	struct sctp_af		*af;
708 	struct sctp_sockaddr_entry *saddr;
709 	int 			i;
710 	int 			retval = 0;
711 
712 	if (!sctp_addip_enable)
713 		return retval;
714 
715 	sp = sctp_sk(sk);
716 	ep = sp->ep;
717 
718 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
719 			  __func__, sk, addrs, addrcnt);
720 
721 	list_for_each_entry(asoc, &ep->asocs, asocs) {
722 
723 		if (!asoc->peer.asconf_capable)
724 			continue;
725 
726 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
727 			continue;
728 
729 		if (!sctp_state(asoc, ESTABLISHED))
730 			continue;
731 
732 		/* Check if any address in the packed array of addresses is
733 		 * not present in the bind address list of the association.
734 		 * If so, do not send the asconf chunk to its peer, but
735 		 * continue with other associations.
736 		 */
737 		addr_buf = addrs;
738 		for (i = 0; i < addrcnt; i++) {
739 			laddr = (union sctp_addr *)addr_buf;
740 			af = sctp_get_af_specific(laddr->v4.sin_family);
741 			if (!af) {
742 				retval = -EINVAL;
743 				goto out;
744 			}
745 
746 			if (!sctp_assoc_lookup_laddr(asoc, laddr))
747 				break;
748 
749 			addr_buf += af->sockaddr_len;
750 		}
751 		if (i < addrcnt)
752 			continue;
753 
754 		/* Find one address in the association's bind address list
755 		 * that is not in the packed array of addresses. This is to
756 		 * make sure that we do not delete all the addresses in the
757 		 * association.
758 		 */
759 		bp = &asoc->base.bind_addr;
760 		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
761 					       addrcnt, sp);
762 		if (!laddr)
763 			continue;
764 
765 		/* We do not need RCU protection throughout this loop
766 		 * because this is done under a socket lock from the
767 		 * setsockopt call.
768 		 */
769 		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
770 						   SCTP_PARAM_DEL_IP);
771 		if (!chunk) {
772 			retval = -ENOMEM;
773 			goto out;
774 		}
775 
776 		/* Reset use_as_src flag for the addresses in the bind address
777 		 * list that are to be deleted.
778 		 */
779 		addr_buf = addrs;
780 		for (i = 0; i < addrcnt; i++) {
781 			laddr = (union sctp_addr *)addr_buf;
782 			af = sctp_get_af_specific(laddr->v4.sin_family);
783 			list_for_each_entry(saddr, &bp->address_list, list) {
784 				if (sctp_cmp_addr_exact(&saddr->a, laddr))
785 					saddr->state = SCTP_ADDR_DEL;
786 			}
787 			addr_buf += af->sockaddr_len;
788 		}
789 
790 		/* Update the route and saddr entries for all the transports
791 		 * as some of the addresses in the bind address list are
792 		 * about to be deleted and cannot be used as source addresses.
793 		 */
794 		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
795 					transports) {
796 			dst_release(transport->dst);
797 			sctp_transport_route(transport, NULL,
798 					     sctp_sk(asoc->base.sk));
799 		}
800 
801 		retval = sctp_send_asconf(asoc, chunk);
802 	}
803 out:
804 	return retval;
805 }
806 
807 /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
808  *
809  * API 8.1
810  * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt,
811  *                int flags);
812  *
813  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
814  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
815  * or IPv6 addresses.
816  *
817  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
818  * Section 3.1.2 for this usage.
819  *
820  * addrs is a pointer to an array of one or more socket addresses. Each
821  * address is contained in its appropriate structure (i.e. struct
822  * sockaddr_in or struct sockaddr_in6) the family of the address type
823  * must be used to distinguish the address length (note that this
824  * representation is termed a "packed array" of addresses). The caller
825  * specifies the number of addresses in the array with addrcnt.
826  *
827  * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns
828  * -1, and sets errno to the appropriate error code.
829  *
830  * For SCTP, the port given in each socket address must be the same, or
831  * sctp_bindx() will fail, setting errno to EINVAL.
832  *
833  * The flags parameter is formed from the bitwise OR of zero or more of
834  * the following currently defined flags:
835  *
836  * SCTP_BINDX_ADD_ADDR
837  *
838  * SCTP_BINDX_REM_ADDR
839  *
840  * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
841  * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given
842  * addresses from the association. The two flags are mutually exclusive;
843  * if both are given, sctp_bindx() will fail with EINVAL. A caller may
844  * not remove all addresses from an association; sctp_bindx() will
845  * reject such an attempt with EINVAL.
846  *
847  * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
848  * additional addresses with an endpoint after calling bind().  Or use
849  * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
850  * socket is associated with so that no new association accepted will be
851  * associated with those addresses. If the endpoint supports dynamic
852  * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
853  * endpoint to send the appropriate message to the peer to change the
854  * peers address lists.
855  *
856  * Adding and removing addresses from a connected association is
857  * optional functionality. Implementations that do not support this
858  * functionality should return EOPNOTSUPP.
859  *
860  * Basically do nothing but copying the addresses from user to kernel
861  * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
862  * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
863  * from userspace.
864  *
865  * We don't use copy_from_user() for optimization: we first do the
866  * sanity checks (buffer size -fast- and access check-healthy
867  * pointer); if all of those succeed, then we can alloc the memory
868  * (expensive operation) needed to copy the data to kernel. Then we do
869  * the copying without checking the user space area
870  * (__copy_from_user()).
871  *
872  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
873  * it.
874  *
875  * sk        The sk of the socket
876  * addrs     The pointer to the addresses in user land
877  * addrssize Size of the addrs buffer
878  * op        Operation to perform (add or remove, see the flags of
879  *           sctp_bindx)
880  *
881  * Returns 0 if ok, <0 errno code on error.
882  */
883 SCTP_STATIC int sctp_setsockopt_bindx(struct sock* sk,
884 				      struct sockaddr __user *addrs,
885 				      int addrs_size, int op)
886 {
887 	struct sockaddr *kaddrs;
888 	int err;
889 	int addrcnt = 0;
890 	int walk_size = 0;
891 	struct sockaddr *sa_addr;
892 	void *addr_buf;
893 	struct sctp_af *af;
894 
895 	SCTP_DEBUG_PRINTK("sctp_setsocktopt_bindx: sk %p addrs %p"
896 			  " addrs_size %d opt %d\n", sk, addrs, addrs_size, op);
897 
898 	if (unlikely(addrs_size <= 0))
899 		return -EINVAL;
900 
901 	/* Check the user passed a healthy pointer.  */
902 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
903 		return -EFAULT;
904 
905 	/* Alloc space for the address array in kernel memory.  */
906 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
907 	if (unlikely(!kaddrs))
908 		return -ENOMEM;
909 
910 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
911 		kfree(kaddrs);
912 		return -EFAULT;
913 	}
914 
915 	/* Walk through the addrs buffer and count the number of addresses. */
916 	addr_buf = kaddrs;
917 	while (walk_size < addrs_size) {
918 		sa_addr = (struct sockaddr *)addr_buf;
919 		af = sctp_get_af_specific(sa_addr->sa_family);
920 
921 		/* If the address family is not supported or if this address
922 		 * causes the address buffer to overflow return EINVAL.
923 		 */
924 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
925 			kfree(kaddrs);
926 			return -EINVAL;
927 		}
928 		addrcnt++;
929 		addr_buf += af->sockaddr_len;
930 		walk_size += af->sockaddr_len;
931 	}
932 
933 	/* Do the work. */
934 	switch (op) {
935 	case SCTP_BINDX_ADD_ADDR:
936 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
937 		if (err)
938 			goto out;
939 		err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
940 		break;
941 
942 	case SCTP_BINDX_REM_ADDR:
943 		err = sctp_bindx_rem(sk, kaddrs, addrcnt);
944 		if (err)
945 			goto out;
946 		err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
947 		break;
948 
949 	default:
950 		err = -EINVAL;
951 		break;
952 	}
953 
954 out:
955 	kfree(kaddrs);
956 
957 	return err;
958 }
959 
960 /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
961  *
962  * Common routine for handling connect() and sctp_connectx().
963  * Connect will come in with just a single address.
964  */
965 static int __sctp_connect(struct sock* sk,
966 			  struct sockaddr *kaddrs,
967 			  int addrs_size,
968 			  sctp_assoc_t *assoc_id)
969 {
970 	struct sctp_sock *sp;
971 	struct sctp_endpoint *ep;
972 	struct sctp_association *asoc = NULL;
973 	struct sctp_association *asoc2;
974 	struct sctp_transport *transport;
975 	union sctp_addr to;
976 	struct sctp_af *af;
977 	sctp_scope_t scope;
978 	long timeo;
979 	int err = 0;
980 	int addrcnt = 0;
981 	int walk_size = 0;
982 	union sctp_addr *sa_addr = NULL;
983 	void *addr_buf;
984 	unsigned short port;
985 	unsigned int f_flags = 0;
986 
987 	sp = sctp_sk(sk);
988 	ep = sp->ep;
989 
990 	/* connect() cannot be done on a socket that is already in ESTABLISHED
991 	 * state - UDP-style peeled off socket or a TCP-style socket that
992 	 * is already connected.
993 	 * It cannot be done even on a TCP-style listening socket.
994 	 */
995 	if (sctp_sstate(sk, ESTABLISHED) ||
996 	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
997 		err = -EISCONN;
998 		goto out_free;
999 	}
1000 
1001 	/* Walk through the addrs buffer and count the number of addresses. */
1002 	addr_buf = kaddrs;
1003 	while (walk_size < addrs_size) {
1004 		sa_addr = (union sctp_addr *)addr_buf;
1005 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
1006 		port = ntohs(sa_addr->v4.sin_port);
1007 
1008 		/* If the address family is not supported or if this address
1009 		 * causes the address buffer to overflow return EINVAL.
1010 		 */
1011 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1012 			err = -EINVAL;
1013 			goto out_free;
1014 		}
1015 
1016 		/* Save current address so we can work with it */
1017 		memcpy(&to, sa_addr, af->sockaddr_len);
1018 
1019 		err = sctp_verify_addr(sk, &to, af->sockaddr_len);
1020 		if (err)
1021 			goto out_free;
1022 
1023 		/* Make sure the destination port is correctly set
1024 		 * in all addresses.
1025 		 */
1026 		if (asoc && asoc->peer.port && asoc->peer.port != port)
1027 			goto out_free;
1028 
1029 
1030 		/* Check if there already is a matching association on the
1031 		 * endpoint (other than the one created here).
1032 		 */
1033 		asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1034 		if (asoc2 && asoc2 != asoc) {
1035 			if (asoc2->state >= SCTP_STATE_ESTABLISHED)
1036 				err = -EISCONN;
1037 			else
1038 				err = -EALREADY;
1039 			goto out_free;
1040 		}
1041 
1042 		/* If we could not find a matching association on the endpoint,
1043 		 * make sure that there is no peeled-off association matching
1044 		 * the peer address even on another socket.
1045 		 */
1046 		if (sctp_endpoint_is_peeled_off(ep, &to)) {
1047 			err = -EADDRNOTAVAIL;
1048 			goto out_free;
1049 		}
1050 
1051 		if (!asoc) {
1052 			/* If a bind() or sctp_bindx() is not called prior to
1053 			 * an sctp_connectx() call, the system picks an
1054 			 * ephemeral port and will choose an address set
1055 			 * equivalent to binding with a wildcard address.
1056 			 */
1057 			if (!ep->base.bind_addr.port) {
1058 				if (sctp_autobind(sk)) {
1059 					err = -EAGAIN;
1060 					goto out_free;
1061 				}
1062 			} else {
1063 				/*
1064 				 * If an unprivileged user inherits a 1-many
1065 				 * style socket with open associations on a
1066 				 * privileged port, it MAY be permitted to
1067 				 * accept new associations, but it SHOULD NOT
1068 				 * be permitted to open new associations.
1069 				 */
1070 				if (ep->base.bind_addr.port < PROT_SOCK &&
1071 				    !capable(CAP_NET_BIND_SERVICE)) {
1072 					err = -EACCES;
1073 					goto out_free;
1074 				}
1075 			}
1076 
1077 			scope = sctp_scope(&to);
1078 			asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1079 			if (!asoc) {
1080 				err = -ENOMEM;
1081 				goto out_free;
1082 			}
1083 
1084 			err = sctp_assoc_set_bind_addr_from_ep(asoc, scope,
1085 							      GFP_KERNEL);
1086 			if (err < 0) {
1087 				goto out_free;
1088 			}
1089 
1090 		}
1091 
1092 		/* Prime the peer's transport structures.  */
1093 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL,
1094 						SCTP_UNKNOWN);
1095 		if (!transport) {
1096 			err = -ENOMEM;
1097 			goto out_free;
1098 		}
1099 
1100 		addrcnt++;
1101 		addr_buf += af->sockaddr_len;
1102 		walk_size += af->sockaddr_len;
1103 	}
1104 
1105 	/* In case the user of sctp_connectx() wants an association
1106 	 * id back, assign one now.
1107 	 */
1108 	if (assoc_id) {
1109 		err = sctp_assoc_set_id(asoc, GFP_KERNEL);
1110 		if (err < 0)
1111 			goto out_free;
1112 	}
1113 
1114 	err = sctp_primitive_ASSOCIATE(asoc, NULL);
1115 	if (err < 0) {
1116 		goto out_free;
1117 	}
1118 
1119 	/* Initialize sk's dport and daddr for getpeername() */
1120 	inet_sk(sk)->dport = htons(asoc->peer.port);
1121 	af = sctp_get_af_specific(sa_addr->sa.sa_family);
1122 	af->to_sk_daddr(sa_addr, sk);
1123 	sk->sk_err = 0;
1124 
1125 	/* in-kernel sockets don't generally have a file allocated to them
1126 	 * if all they do is call sock_create_kern().
1127 	 */
1128 	if (sk->sk_socket->file)
1129 		f_flags = sk->sk_socket->file->f_flags;
1130 
1131 	timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK);
1132 
1133 	err = sctp_wait_for_connect(asoc, &timeo);
1134 	if ((err == 0 || err == -EINPROGRESS) && assoc_id)
1135 		*assoc_id = asoc->assoc_id;
1136 
1137 	/* Don't free association on exit. */
1138 	asoc = NULL;
1139 
1140 out_free:
1141 
1142 	SCTP_DEBUG_PRINTK("About to exit __sctp_connect() free asoc: %p"
1143 			  " kaddrs: %p err: %d\n",
1144 			  asoc, kaddrs, err);
1145 	if (asoc)
1146 		sctp_association_free(asoc);
1147 	return err;
1148 }
1149 
1150 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
1151  *
1152  * API 8.9
1153  * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt,
1154  * 			sctp_assoc_t *asoc);
1155  *
1156  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
1157  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
1158  * or IPv6 addresses.
1159  *
1160  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
1161  * Section 3.1.2 for this usage.
1162  *
1163  * addrs is a pointer to an array of one or more socket addresses. Each
1164  * address is contained in its appropriate structure (i.e. struct
1165  * sockaddr_in or struct sockaddr_in6) the family of the address type
1166  * must be used to distengish the address length (note that this
1167  * representation is termed a "packed array" of addresses). The caller
1168  * specifies the number of addresses in the array with addrcnt.
1169  *
1170  * On success, sctp_connectx() returns 0. It also sets the assoc_id to
1171  * the association id of the new association.  On failure, sctp_connectx()
1172  * returns -1, and sets errno to the appropriate error code.  The assoc_id
1173  * is not touched by the kernel.
1174  *
1175  * For SCTP, the port given in each socket address must be the same, or
1176  * sctp_connectx() will fail, setting errno to EINVAL.
1177  *
1178  * An application can use sctp_connectx to initiate an association with
1179  * an endpoint that is multi-homed.  Much like sctp_bindx() this call
1180  * allows a caller to specify multiple addresses at which a peer can be
1181  * reached.  The way the SCTP stack uses the list of addresses to set up
1182  * the association is implementation dependant.  This function only
1183  * specifies that the stack will try to make use of all the addresses in
1184  * the list when needed.
1185  *
1186  * Note that the list of addresses passed in is only used for setting up
1187  * the association.  It does not necessarily equal the set of addresses
1188  * the peer uses for the resulting association.  If the caller wants to
1189  * find out the set of peer addresses, it must use sctp_getpaddrs() to
1190  * retrieve them after the association has been set up.
1191  *
1192  * Basically do nothing but copying the addresses from user to kernel
1193  * land and invoking either sctp_connectx(). This is used for tunneling
1194  * the sctp_connectx() request through sctp_setsockopt() from userspace.
1195  *
1196  * We don't use copy_from_user() for optimization: we first do the
1197  * sanity checks (buffer size -fast- and access check-healthy
1198  * pointer); if all of those succeed, then we can alloc the memory
1199  * (expensive operation) needed to copy the data to kernel. Then we do
1200  * the copying without checking the user space area
1201  * (__copy_from_user()).
1202  *
1203  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
1204  * it.
1205  *
1206  * sk        The sk of the socket
1207  * addrs     The pointer to the addresses in user land
1208  * addrssize Size of the addrs buffer
1209  *
1210  * Returns >=0 if ok, <0 errno code on error.
1211  */
1212 SCTP_STATIC int __sctp_setsockopt_connectx(struct sock* sk,
1213 				      struct sockaddr __user *addrs,
1214 				      int addrs_size,
1215 				      sctp_assoc_t *assoc_id)
1216 {
1217 	int err = 0;
1218 	struct sockaddr *kaddrs;
1219 
1220 	SCTP_DEBUG_PRINTK("%s - sk %p addrs %p addrs_size %d\n",
1221 			  __func__, sk, addrs, addrs_size);
1222 
1223 	if (unlikely(addrs_size <= 0))
1224 		return -EINVAL;
1225 
1226 	/* Check the user passed a healthy pointer.  */
1227 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
1228 		return -EFAULT;
1229 
1230 	/* Alloc space for the address array in kernel memory.  */
1231 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
1232 	if (unlikely(!kaddrs))
1233 		return -ENOMEM;
1234 
1235 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
1236 		err = -EFAULT;
1237 	} else {
1238 		err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
1239 	}
1240 
1241 	kfree(kaddrs);
1242 
1243 	return err;
1244 }
1245 
1246 /*
1247  * This is an older interface.  It's kept for backward compatibility
1248  * to the option that doesn't provide association id.
1249  */
1250 SCTP_STATIC int sctp_setsockopt_connectx_old(struct sock* sk,
1251 				      struct sockaddr __user *addrs,
1252 				      int addrs_size)
1253 {
1254 	return __sctp_setsockopt_connectx(sk, addrs, addrs_size, NULL);
1255 }
1256 
1257 /*
1258  * New interface for the API.  The since the API is done with a socket
1259  * option, to make it simple we feed back the association id is as a return
1260  * indication to the call.  Error is always negative and association id is
1261  * always positive.
1262  */
1263 SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
1264 				      struct sockaddr __user *addrs,
1265 				      int addrs_size)
1266 {
1267 	sctp_assoc_t assoc_id = 0;
1268 	int err = 0;
1269 
1270 	err = __sctp_setsockopt_connectx(sk, addrs, addrs_size, &assoc_id);
1271 
1272 	if (err)
1273 		return err;
1274 	else
1275 		return assoc_id;
1276 }
1277 
1278 /*
1279  * New (hopefully final) interface for the API.
1280  * We use the sctp_getaddrs_old structure so that use-space library
1281  * can avoid any unnecessary allocations.   The only defferent part
1282  * is that we store the actual length of the address buffer into the
1283  * addrs_num structure member.  That way we can re-use the existing
1284  * code.
1285  */
1286 SCTP_STATIC int sctp_getsockopt_connectx3(struct sock* sk, int len,
1287 					char __user *optval,
1288 					int __user *optlen)
1289 {
1290 	struct sctp_getaddrs_old param;
1291 	sctp_assoc_t assoc_id = 0;
1292 	int err = 0;
1293 
1294 	if (len < sizeof(param))
1295 		return -EINVAL;
1296 
1297 	if (copy_from_user(&param, optval, sizeof(param)))
1298 		return -EFAULT;
1299 
1300 	err = __sctp_setsockopt_connectx(sk,
1301 			(struct sockaddr __user *)param.addrs,
1302 			param.addr_num, &assoc_id);
1303 
1304 	if (err == 0 || err == -EINPROGRESS) {
1305 		if (copy_to_user(optval, &assoc_id, sizeof(assoc_id)))
1306 			return -EFAULT;
1307 		if (put_user(sizeof(assoc_id), optlen))
1308 			return -EFAULT;
1309 	}
1310 
1311 	return err;
1312 }
1313 
1314 /* API 3.1.4 close() - UDP Style Syntax
1315  * Applications use close() to perform graceful shutdown (as described in
1316  * Section 10.1 of [SCTP]) on ALL the associations currently represented
1317  * by a UDP-style socket.
1318  *
1319  * The syntax is
1320  *
1321  *   ret = close(int sd);
1322  *
1323  *   sd      - the socket descriptor of the associations to be closed.
1324  *
1325  * To gracefully shutdown a specific association represented by the
1326  * UDP-style socket, an application should use the sendmsg() call,
1327  * passing no user data, but including the appropriate flag in the
1328  * ancillary data (see Section xxxx).
1329  *
1330  * If sd in the close() call is a branched-off socket representing only
1331  * one association, the shutdown is performed on that association only.
1332  *
1333  * 4.1.6 close() - TCP Style Syntax
1334  *
1335  * Applications use close() to gracefully close down an association.
1336  *
1337  * The syntax is:
1338  *
1339  *    int close(int sd);
1340  *
1341  *      sd      - the socket descriptor of the association to be closed.
1342  *
1343  * After an application calls close() on a socket descriptor, no further
1344  * socket operations will succeed on that descriptor.
1345  *
1346  * API 7.1.4 SO_LINGER
1347  *
1348  * An application using the TCP-style socket can use this option to
1349  * perform the SCTP ABORT primitive.  The linger option structure is:
1350  *
1351  *  struct  linger {
1352  *     int     l_onoff;                // option on/off
1353  *     int     l_linger;               // linger time
1354  * };
1355  *
1356  * To enable the option, set l_onoff to 1.  If the l_linger value is set
1357  * to 0, calling close() is the same as the ABORT primitive.  If the
1358  * value is set to a negative value, the setsockopt() call will return
1359  * an error.  If the value is set to a positive value linger_time, the
1360  * close() can be blocked for at most linger_time ms.  If the graceful
1361  * shutdown phase does not finish during this period, close() will
1362  * return but the graceful shutdown phase continues in the system.
1363  */
1364 SCTP_STATIC void sctp_close(struct sock *sk, long timeout)
1365 {
1366 	struct sctp_endpoint *ep;
1367 	struct sctp_association *asoc;
1368 	struct list_head *pos, *temp;
1369 
1370 	SCTP_DEBUG_PRINTK("sctp_close(sk: 0x%p, timeout:%ld)\n", sk, timeout);
1371 
1372 	sctp_lock_sock(sk);
1373 	sk->sk_shutdown = SHUTDOWN_MASK;
1374 	sk->sk_state = SCTP_SS_CLOSING;
1375 
1376 	ep = sctp_sk(sk)->ep;
1377 
1378 	/* Walk all associations on an endpoint.  */
1379 	list_for_each_safe(pos, temp, &ep->asocs) {
1380 		asoc = list_entry(pos, struct sctp_association, asocs);
1381 
1382 		if (sctp_style(sk, TCP)) {
1383 			/* A closed association can still be in the list if
1384 			 * it belongs to a TCP-style listening socket that is
1385 			 * not yet accepted. If so, free it. If not, send an
1386 			 * ABORT or SHUTDOWN based on the linger options.
1387 			 */
1388 			if (sctp_state(asoc, CLOSED)) {
1389 				sctp_unhash_established(asoc);
1390 				sctp_association_free(asoc);
1391 				continue;
1392 			}
1393 		}
1394 
1395 		if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
1396 			struct sctp_chunk *chunk;
1397 
1398 			chunk = sctp_make_abort_user(asoc, NULL, 0);
1399 			if (chunk)
1400 				sctp_primitive_ABORT(asoc, chunk);
1401 		} else
1402 			sctp_primitive_SHUTDOWN(asoc, NULL);
1403 	}
1404 
1405 	/* Clean up any skbs sitting on the receive queue.  */
1406 	sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
1407 	sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
1408 
1409 	/* On a TCP-style socket, block for at most linger_time if set. */
1410 	if (sctp_style(sk, TCP) && timeout)
1411 		sctp_wait_for_close(sk, timeout);
1412 
1413 	/* This will run the backlog queue.  */
1414 	sctp_release_sock(sk);
1415 
1416 	/* Supposedly, no process has access to the socket, but
1417 	 * the net layers still may.
1418 	 */
1419 	sctp_local_bh_disable();
1420 	sctp_bh_lock_sock(sk);
1421 
1422 	/* Hold the sock, since sk_common_release() will put sock_put()
1423 	 * and we have just a little more cleanup.
1424 	 */
1425 	sock_hold(sk);
1426 	sk_common_release(sk);
1427 
1428 	sctp_bh_unlock_sock(sk);
1429 	sctp_local_bh_enable();
1430 
1431 	sock_put(sk);
1432 
1433 	SCTP_DBG_OBJCNT_DEC(sock);
1434 }
1435 
1436 /* Handle EPIPE error. */
1437 static int sctp_error(struct sock *sk, int flags, int err)
1438 {
1439 	if (err == -EPIPE)
1440 		err = sock_error(sk) ? : -EPIPE;
1441 	if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
1442 		send_sig(SIGPIPE, current, 0);
1443 	return err;
1444 }
1445 
1446 /* API 3.1.3 sendmsg() - UDP Style Syntax
1447  *
1448  * An application uses sendmsg() and recvmsg() calls to transmit data to
1449  * and receive data from its peer.
1450  *
1451  *  ssize_t sendmsg(int socket, const struct msghdr *message,
1452  *                  int flags);
1453  *
1454  *  socket  - the socket descriptor of the endpoint.
1455  *  message - pointer to the msghdr structure which contains a single
1456  *            user message and possibly some ancillary data.
1457  *
1458  *            See Section 5 for complete description of the data
1459  *            structures.
1460  *
1461  *  flags   - flags sent or received with the user message, see Section
1462  *            5 for complete description of the flags.
1463  *
1464  * Note:  This function could use a rewrite especially when explicit
1465  * connect support comes in.
1466  */
1467 /* BUG:  We do not implement the equivalent of sk_stream_wait_memory(). */
1468 
1469 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
1470 
1471 SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
1472 			     struct msghdr *msg, size_t msg_len)
1473 {
1474 	struct sctp_sock *sp;
1475 	struct sctp_endpoint *ep;
1476 	struct sctp_association *new_asoc=NULL, *asoc=NULL;
1477 	struct sctp_transport *transport, *chunk_tp;
1478 	struct sctp_chunk *chunk;
1479 	union sctp_addr to;
1480 	struct sockaddr *msg_name = NULL;
1481 	struct sctp_sndrcvinfo default_sinfo = { 0 };
1482 	struct sctp_sndrcvinfo *sinfo;
1483 	struct sctp_initmsg *sinit;
1484 	sctp_assoc_t associd = 0;
1485 	sctp_cmsgs_t cmsgs = { NULL };
1486 	int err;
1487 	sctp_scope_t scope;
1488 	long timeo;
1489 	__u16 sinfo_flags = 0;
1490 	struct sctp_datamsg *datamsg;
1491 	int msg_flags = msg->msg_flags;
1492 
1493 	SCTP_DEBUG_PRINTK("sctp_sendmsg(sk: %p, msg: %p, msg_len: %zu)\n",
1494 			  sk, msg, msg_len);
1495 
1496 	err = 0;
1497 	sp = sctp_sk(sk);
1498 	ep = sp->ep;
1499 
1500 	SCTP_DEBUG_PRINTK("Using endpoint: %p.\n", ep);
1501 
1502 	/* We cannot send a message over a TCP-style listening socket. */
1503 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) {
1504 		err = -EPIPE;
1505 		goto out_nounlock;
1506 	}
1507 
1508 	/* Parse out the SCTP CMSGs.  */
1509 	err = sctp_msghdr_parse(msg, &cmsgs);
1510 
1511 	if (err) {
1512 		SCTP_DEBUG_PRINTK("msghdr parse err = %x\n", err);
1513 		goto out_nounlock;
1514 	}
1515 
1516 	/* Fetch the destination address for this packet.  This
1517 	 * address only selects the association--it is not necessarily
1518 	 * the address we will send to.
1519 	 * For a peeled-off socket, msg_name is ignored.
1520 	 */
1521 	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
1522 		int msg_namelen = msg->msg_namelen;
1523 
1524 		err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
1525 				       msg_namelen);
1526 		if (err)
1527 			return err;
1528 
1529 		if (msg_namelen > sizeof(to))
1530 			msg_namelen = sizeof(to);
1531 		memcpy(&to, msg->msg_name, msg_namelen);
1532 		msg_name = msg->msg_name;
1533 	}
1534 
1535 	sinfo = cmsgs.info;
1536 	sinit = cmsgs.init;
1537 
1538 	/* Did the user specify SNDRCVINFO?  */
1539 	if (sinfo) {
1540 		sinfo_flags = sinfo->sinfo_flags;
1541 		associd = sinfo->sinfo_assoc_id;
1542 	}
1543 
1544 	SCTP_DEBUG_PRINTK("msg_len: %zu, sinfo_flags: 0x%x\n",
1545 			  msg_len, sinfo_flags);
1546 
1547 	/* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */
1548 	if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) {
1549 		err = -EINVAL;
1550 		goto out_nounlock;
1551 	}
1552 
1553 	/* If SCTP_EOF is set, no data can be sent. Disallow sending zero
1554 	 * length messages when SCTP_EOF|SCTP_ABORT is not set.
1555 	 * If SCTP_ABORT is set, the message length could be non zero with
1556 	 * the msg_iov set to the user abort reason.
1557 	 */
1558 	if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) ||
1559 	    (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) {
1560 		err = -EINVAL;
1561 		goto out_nounlock;
1562 	}
1563 
1564 	/* If SCTP_ADDR_OVER is set, there must be an address
1565 	 * specified in msg_name.
1566 	 */
1567 	if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) {
1568 		err = -EINVAL;
1569 		goto out_nounlock;
1570 	}
1571 
1572 	transport = NULL;
1573 
1574 	SCTP_DEBUG_PRINTK("About to look up association.\n");
1575 
1576 	sctp_lock_sock(sk);
1577 
1578 	/* If a msg_name has been specified, assume this is to be used.  */
1579 	if (msg_name) {
1580 		/* Look for a matching association on the endpoint. */
1581 		asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1582 		if (!asoc) {
1583 			/* If we could not find a matching association on the
1584 			 * endpoint, make sure that it is not a TCP-style
1585 			 * socket that already has an association or there is
1586 			 * no peeled-off association on another socket.
1587 			 */
1588 			if ((sctp_style(sk, TCP) &&
1589 			     sctp_sstate(sk, ESTABLISHED)) ||
1590 			    sctp_endpoint_is_peeled_off(ep, &to)) {
1591 				err = -EADDRNOTAVAIL;
1592 				goto out_unlock;
1593 			}
1594 		}
1595 	} else {
1596 		asoc = sctp_id2assoc(sk, associd);
1597 		if (!asoc) {
1598 			err = -EPIPE;
1599 			goto out_unlock;
1600 		}
1601 	}
1602 
1603 	if (asoc) {
1604 		SCTP_DEBUG_PRINTK("Just looked up association: %p.\n", asoc);
1605 
1606 		/* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED
1607 		 * socket that has an association in CLOSED state. This can
1608 		 * happen when an accepted socket has an association that is
1609 		 * already CLOSED.
1610 		 */
1611 		if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) {
1612 			err = -EPIPE;
1613 			goto out_unlock;
1614 		}
1615 
1616 		if (sinfo_flags & SCTP_EOF) {
1617 			SCTP_DEBUG_PRINTK("Shutting down association: %p\n",
1618 					  asoc);
1619 			sctp_primitive_SHUTDOWN(asoc, NULL);
1620 			err = 0;
1621 			goto out_unlock;
1622 		}
1623 		if (sinfo_flags & SCTP_ABORT) {
1624 
1625 			chunk = sctp_make_abort_user(asoc, msg, msg_len);
1626 			if (!chunk) {
1627 				err = -ENOMEM;
1628 				goto out_unlock;
1629 			}
1630 
1631 			SCTP_DEBUG_PRINTK("Aborting association: %p\n", asoc);
1632 			sctp_primitive_ABORT(asoc, chunk);
1633 			err = 0;
1634 			goto out_unlock;
1635 		}
1636 	}
1637 
1638 	/* Do we need to create the association?  */
1639 	if (!asoc) {
1640 		SCTP_DEBUG_PRINTK("There is no association yet.\n");
1641 
1642 		if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) {
1643 			err = -EINVAL;
1644 			goto out_unlock;
1645 		}
1646 
1647 		/* Check for invalid stream against the stream counts,
1648 		 * either the default or the user specified stream counts.
1649 		 */
1650 		if (sinfo) {
1651 			if (!sinit || (sinit && !sinit->sinit_num_ostreams)) {
1652 				/* Check against the defaults. */
1653 				if (sinfo->sinfo_stream >=
1654 				    sp->initmsg.sinit_num_ostreams) {
1655 					err = -EINVAL;
1656 					goto out_unlock;
1657 				}
1658 			} else {
1659 				/* Check against the requested.  */
1660 				if (sinfo->sinfo_stream >=
1661 				    sinit->sinit_num_ostreams) {
1662 					err = -EINVAL;
1663 					goto out_unlock;
1664 				}
1665 			}
1666 		}
1667 
1668 		/*
1669 		 * API 3.1.2 bind() - UDP Style Syntax
1670 		 * If a bind() or sctp_bindx() is not called prior to a
1671 		 * sendmsg() call that initiates a new association, the
1672 		 * system picks an ephemeral port and will choose an address
1673 		 * set equivalent to binding with a wildcard address.
1674 		 */
1675 		if (!ep->base.bind_addr.port) {
1676 			if (sctp_autobind(sk)) {
1677 				err = -EAGAIN;
1678 				goto out_unlock;
1679 			}
1680 		} else {
1681 			/*
1682 			 * If an unprivileged user inherits a one-to-many
1683 			 * style socket with open associations on a privileged
1684 			 * port, it MAY be permitted to accept new associations,
1685 			 * but it SHOULD NOT be permitted to open new
1686 			 * associations.
1687 			 */
1688 			if (ep->base.bind_addr.port < PROT_SOCK &&
1689 			    !capable(CAP_NET_BIND_SERVICE)) {
1690 				err = -EACCES;
1691 				goto out_unlock;
1692 			}
1693 		}
1694 
1695 		scope = sctp_scope(&to);
1696 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1697 		if (!new_asoc) {
1698 			err = -ENOMEM;
1699 			goto out_unlock;
1700 		}
1701 		asoc = new_asoc;
1702 		err = sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL);
1703 		if (err < 0) {
1704 			err = -ENOMEM;
1705 			goto out_free;
1706 		}
1707 
1708 		/* If the SCTP_INIT ancillary data is specified, set all
1709 		 * the association init values accordingly.
1710 		 */
1711 		if (sinit) {
1712 			if (sinit->sinit_num_ostreams) {
1713 				asoc->c.sinit_num_ostreams =
1714 					sinit->sinit_num_ostreams;
1715 			}
1716 			if (sinit->sinit_max_instreams) {
1717 				asoc->c.sinit_max_instreams =
1718 					sinit->sinit_max_instreams;
1719 			}
1720 			if (sinit->sinit_max_attempts) {
1721 				asoc->max_init_attempts
1722 					= sinit->sinit_max_attempts;
1723 			}
1724 			if (sinit->sinit_max_init_timeo) {
1725 				asoc->max_init_timeo =
1726 				 msecs_to_jiffies(sinit->sinit_max_init_timeo);
1727 			}
1728 		}
1729 
1730 		/* Prime the peer's transport structures.  */
1731 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN);
1732 		if (!transport) {
1733 			err = -ENOMEM;
1734 			goto out_free;
1735 		}
1736 	}
1737 
1738 	/* ASSERT: we have a valid association at this point.  */
1739 	SCTP_DEBUG_PRINTK("We have a valid association.\n");
1740 
1741 	if (!sinfo) {
1742 		/* If the user didn't specify SNDRCVINFO, make up one with
1743 		 * some defaults.
1744 		 */
1745 		default_sinfo.sinfo_stream = asoc->default_stream;
1746 		default_sinfo.sinfo_flags = asoc->default_flags;
1747 		default_sinfo.sinfo_ppid = asoc->default_ppid;
1748 		default_sinfo.sinfo_context = asoc->default_context;
1749 		default_sinfo.sinfo_timetolive = asoc->default_timetolive;
1750 		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
1751 		sinfo = &default_sinfo;
1752 	}
1753 
1754 	/* API 7.1.7, the sndbuf size per association bounds the
1755 	 * maximum size of data that can be sent in a single send call.
1756 	 */
1757 	if (msg_len > sk->sk_sndbuf) {
1758 		err = -EMSGSIZE;
1759 		goto out_free;
1760 	}
1761 
1762 	if (asoc->pmtu_pending)
1763 		sctp_assoc_pending_pmtu(asoc);
1764 
1765 	/* If fragmentation is disabled and the message length exceeds the
1766 	 * association fragmentation point, return EMSGSIZE.  The I-D
1767 	 * does not specify what this error is, but this looks like
1768 	 * a great fit.
1769 	 */
1770 	if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
1771 		err = -EMSGSIZE;
1772 		goto out_free;
1773 	}
1774 
1775 	if (sinfo) {
1776 		/* Check for invalid stream. */
1777 		if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) {
1778 			err = -EINVAL;
1779 			goto out_free;
1780 		}
1781 	}
1782 
1783 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1784 	if (!sctp_wspace(asoc)) {
1785 		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
1786 		if (err)
1787 			goto out_free;
1788 	}
1789 
1790 	/* If an address is passed with the sendto/sendmsg call, it is used
1791 	 * to override the primary destination address in the TCP model, or
1792 	 * when SCTP_ADDR_OVER flag is set in the UDP model.
1793 	 */
1794 	if ((sctp_style(sk, TCP) && msg_name) ||
1795 	    (sinfo_flags & SCTP_ADDR_OVER)) {
1796 		chunk_tp = sctp_assoc_lookup_paddr(asoc, &to);
1797 		if (!chunk_tp) {
1798 			err = -EINVAL;
1799 			goto out_free;
1800 		}
1801 	} else
1802 		chunk_tp = NULL;
1803 
1804 	/* Auto-connect, if we aren't connected already. */
1805 	if (sctp_state(asoc, CLOSED)) {
1806 		err = sctp_primitive_ASSOCIATE(asoc, NULL);
1807 		if (err < 0)
1808 			goto out_free;
1809 		SCTP_DEBUG_PRINTK("We associated primitively.\n");
1810 	}
1811 
1812 	/* Break the message into multiple chunks of maximum size. */
1813 	datamsg = sctp_datamsg_from_user(asoc, sinfo, msg, msg_len);
1814 	if (!datamsg) {
1815 		err = -ENOMEM;
1816 		goto out_free;
1817 	}
1818 
1819 	/* Now send the (possibly) fragmented message. */
1820 	list_for_each_entry(chunk, &datamsg->chunks, frag_list) {
1821 		sctp_chunk_hold(chunk);
1822 
1823 		/* Do accounting for the write space.  */
1824 		sctp_set_owner_w(chunk);
1825 
1826 		chunk->transport = chunk_tp;
1827 	}
1828 
1829 	/* Send it to the lower layers.  Note:  all chunks
1830 	 * must either fail or succeed.   The lower layer
1831 	 * works that way today.  Keep it that way or this
1832 	 * breaks.
1833 	 */
1834 	err = sctp_primitive_SEND(asoc, datamsg);
1835 	/* Did the lower layer accept the chunk? */
1836 	if (err)
1837 		sctp_datamsg_free(datamsg);
1838 	else
1839 		sctp_datamsg_put(datamsg);
1840 
1841 	SCTP_DEBUG_PRINTK("We sent primitively.\n");
1842 
1843 	if (err)
1844 		goto out_free;
1845 	else
1846 		err = msg_len;
1847 
1848 	/* If we are already past ASSOCIATE, the lower
1849 	 * layers are responsible for association cleanup.
1850 	 */
1851 	goto out_unlock;
1852 
1853 out_free:
1854 	if (new_asoc)
1855 		sctp_association_free(asoc);
1856 out_unlock:
1857 	sctp_release_sock(sk);
1858 
1859 out_nounlock:
1860 	return sctp_error(sk, msg_flags, err);
1861 
1862 #if 0
1863 do_sock_err:
1864 	if (msg_len)
1865 		err = msg_len;
1866 	else
1867 		err = sock_error(sk);
1868 	goto out;
1869 
1870 do_interrupted:
1871 	if (msg_len)
1872 		err = msg_len;
1873 	goto out;
1874 #endif /* 0 */
1875 }
1876 
1877 /* This is an extended version of skb_pull() that removes the data from the
1878  * start of a skb even when data is spread across the list of skb's in the
1879  * frag_list. len specifies the total amount of data that needs to be removed.
1880  * when 'len' bytes could be removed from the skb, it returns 0.
1881  * If 'len' exceeds the total skb length,  it returns the no. of bytes that
1882  * could not be removed.
1883  */
1884 static int sctp_skb_pull(struct sk_buff *skb, int len)
1885 {
1886 	struct sk_buff *list;
1887 	int skb_len = skb_headlen(skb);
1888 	int rlen;
1889 
1890 	if (len <= skb_len) {
1891 		__skb_pull(skb, len);
1892 		return 0;
1893 	}
1894 	len -= skb_len;
1895 	__skb_pull(skb, skb_len);
1896 
1897 	skb_walk_frags(skb, list) {
1898 		rlen = sctp_skb_pull(list, len);
1899 		skb->len -= (len-rlen);
1900 		skb->data_len -= (len-rlen);
1901 
1902 		if (!rlen)
1903 			return 0;
1904 
1905 		len = rlen;
1906 	}
1907 
1908 	return len;
1909 }
1910 
1911 /* API 3.1.3  recvmsg() - UDP Style Syntax
1912  *
1913  *  ssize_t recvmsg(int socket, struct msghdr *message,
1914  *                    int flags);
1915  *
1916  *  socket  - the socket descriptor of the endpoint.
1917  *  message - pointer to the msghdr structure which contains a single
1918  *            user message and possibly some ancillary data.
1919  *
1920  *            See Section 5 for complete description of the data
1921  *            structures.
1922  *
1923  *  flags   - flags sent or received with the user message, see Section
1924  *            5 for complete description of the flags.
1925  */
1926 static struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);
1927 
1928 SCTP_STATIC int sctp_recvmsg(struct kiocb *iocb, struct sock *sk,
1929 			     struct msghdr *msg, size_t len, int noblock,
1930 			     int flags, int *addr_len)
1931 {
1932 	struct sctp_ulpevent *event = NULL;
1933 	struct sctp_sock *sp = sctp_sk(sk);
1934 	struct sk_buff *skb;
1935 	int copied;
1936 	int err = 0;
1937 	int skb_len;
1938 
1939 	SCTP_DEBUG_PRINTK("sctp_recvmsg(%s: %p, %s: %p, %s: %zd, %s: %d, %s: "
1940 			  "0x%x, %s: %p)\n", "sk", sk, "msghdr", msg,
1941 			  "len", len, "knoblauch", noblock,
1942 			  "flags", flags, "addr_len", addr_len);
1943 
1944 	sctp_lock_sock(sk);
1945 
1946 	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED)) {
1947 		err = -ENOTCONN;
1948 		goto out;
1949 	}
1950 
1951 	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
1952 	if (!skb)
1953 		goto out;
1954 
1955 	/* Get the total length of the skb including any skb's in the
1956 	 * frag_list.
1957 	 */
1958 	skb_len = skb->len;
1959 
1960 	copied = skb_len;
1961 	if (copied > len)
1962 		copied = len;
1963 
1964 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1965 
1966 	event = sctp_skb2event(skb);
1967 
1968 	if (err)
1969 		goto out_free;
1970 
1971 	sock_recv_timestamp(msg, sk, skb);
1972 	if (sctp_ulpevent_is_notification(event)) {
1973 		msg->msg_flags |= MSG_NOTIFICATION;
1974 		sp->pf->event_msgname(event, msg->msg_name, addr_len);
1975 	} else {
1976 		sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
1977 	}
1978 
1979 	/* Check if we allow SCTP_SNDRCVINFO. */
1980 	if (sp->subscribe.sctp_data_io_event)
1981 		sctp_ulpevent_read_sndrcvinfo(event, msg);
1982 #if 0
1983 	/* FIXME: we should be calling IP/IPv6 layers.  */
1984 	if (sk->sk_protinfo.af_inet.cmsg_flags)
1985 		ip_cmsg_recv(msg, skb);
1986 #endif
1987 
1988 	err = copied;
1989 
1990 	/* If skb's length exceeds the user's buffer, update the skb and
1991 	 * push it back to the receive_queue so that the next call to
1992 	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
1993 	 */
1994 	if (skb_len > copied) {
1995 		msg->msg_flags &= ~MSG_EOR;
1996 		if (flags & MSG_PEEK)
1997 			goto out_free;
1998 		sctp_skb_pull(skb, copied);
1999 		skb_queue_head(&sk->sk_receive_queue, skb);
2000 
2001 		/* When only partial message is copied to the user, increase
2002 		 * rwnd by that amount. If all the data in the skb is read,
2003 		 * rwnd is updated when the event is freed.
2004 		 */
2005 		if (!sctp_ulpevent_is_notification(event))
2006 			sctp_assoc_rwnd_increase(event->asoc, copied);
2007 		goto out;
2008 	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
2009 		   (event->msg_flags & MSG_EOR))
2010 		msg->msg_flags |= MSG_EOR;
2011 	else
2012 		msg->msg_flags &= ~MSG_EOR;
2013 
2014 out_free:
2015 	if (flags & MSG_PEEK) {
2016 		/* Release the skb reference acquired after peeking the skb in
2017 		 * sctp_skb_recv_datagram().
2018 		 */
2019 		kfree_skb(skb);
2020 	} else {
2021 		/* Free the event which includes releasing the reference to
2022 		 * the owner of the skb, freeing the skb and updating the
2023 		 * rwnd.
2024 		 */
2025 		sctp_ulpevent_free(event);
2026 	}
2027 out:
2028 	sctp_release_sock(sk);
2029 	return err;
2030 }
2031 
2032 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
2033  *
2034  * This option is a on/off flag.  If enabled no SCTP message
2035  * fragmentation will be performed.  Instead if a message being sent
2036  * exceeds the current PMTU size, the message will NOT be sent and
2037  * instead a error will be indicated to the user.
2038  */
2039 static int sctp_setsockopt_disable_fragments(struct sock *sk,
2040 					     char __user *optval,
2041 					     unsigned int optlen)
2042 {
2043 	int val;
2044 
2045 	if (optlen < sizeof(int))
2046 		return -EINVAL;
2047 
2048 	if (get_user(val, (int __user *)optval))
2049 		return -EFAULT;
2050 
2051 	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
2052 
2053 	return 0;
2054 }
2055 
2056 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
2057 				  unsigned int optlen)
2058 {
2059 	if (optlen > sizeof(struct sctp_event_subscribe))
2060 		return -EINVAL;
2061 	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
2062 		return -EFAULT;
2063 	return 0;
2064 }
2065 
2066 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
2067  *
2068  * This socket option is applicable to the UDP-style socket only.  When
2069  * set it will cause associations that are idle for more than the
2070  * specified number of seconds to automatically close.  An association
2071  * being idle is defined an association that has NOT sent or received
2072  * user data.  The special value of '0' indicates that no automatic
2073  * close of any associations should be performed.  The option expects an
2074  * integer defining the number of seconds of idle time before an
2075  * association is closed.
2076  */
2077 static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
2078 				     unsigned int optlen)
2079 {
2080 	struct sctp_sock *sp = sctp_sk(sk);
2081 
2082 	/* Applicable to UDP-style socket only */
2083 	if (sctp_style(sk, TCP))
2084 		return -EOPNOTSUPP;
2085 	if (optlen != sizeof(int))
2086 		return -EINVAL;
2087 	if (copy_from_user(&sp->autoclose, optval, optlen))
2088 		return -EFAULT;
2089 
2090 	return 0;
2091 }
2092 
2093 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
2094  *
2095  * Applications can enable or disable heartbeats for any peer address of
2096  * an association, modify an address's heartbeat interval, force a
2097  * heartbeat to be sent immediately, and adjust the address's maximum
2098  * number of retransmissions sent before an address is considered
2099  * unreachable.  The following structure is used to access and modify an
2100  * address's parameters:
2101  *
2102  *  struct sctp_paddrparams {
2103  *     sctp_assoc_t            spp_assoc_id;
2104  *     struct sockaddr_storage spp_address;
2105  *     uint32_t                spp_hbinterval;
2106  *     uint16_t                spp_pathmaxrxt;
2107  *     uint32_t                spp_pathmtu;
2108  *     uint32_t                spp_sackdelay;
2109  *     uint32_t                spp_flags;
2110  * };
2111  *
2112  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
2113  *                     application, and identifies the association for
2114  *                     this query.
2115  *   spp_address     - This specifies which address is of interest.
2116  *   spp_hbinterval  - This contains the value of the heartbeat interval,
2117  *                     in milliseconds.  If a  value of zero
2118  *                     is present in this field then no changes are to
2119  *                     be made to this parameter.
2120  *   spp_pathmaxrxt  - This contains the maximum number of
2121  *                     retransmissions before this address shall be
2122  *                     considered unreachable. If a  value of zero
2123  *                     is present in this field then no changes are to
2124  *                     be made to this parameter.
2125  *   spp_pathmtu     - When Path MTU discovery is disabled the value
2126  *                     specified here will be the "fixed" path mtu.
2127  *                     Note that if the spp_address field is empty
2128  *                     then all associations on this address will
2129  *                     have this fixed path mtu set upon them.
2130  *
2131  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
2132  *                     the number of milliseconds that sacks will be delayed
2133  *                     for. This value will apply to all addresses of an
2134  *                     association if the spp_address field is empty. Note
2135  *                     also, that if delayed sack is enabled and this
2136  *                     value is set to 0, no change is made to the last
2137  *                     recorded delayed sack timer value.
2138  *
2139  *   spp_flags       - These flags are used to control various features
2140  *                     on an association. The flag field may contain
2141  *                     zero or more of the following options.
2142  *
2143  *                     SPP_HB_ENABLE  - Enable heartbeats on the
2144  *                     specified address. Note that if the address
2145  *                     field is empty all addresses for the association
2146  *                     have heartbeats enabled upon them.
2147  *
2148  *                     SPP_HB_DISABLE - Disable heartbeats on the
2149  *                     speicifed address. Note that if the address
2150  *                     field is empty all addresses for the association
2151  *                     will have their heartbeats disabled. Note also
2152  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
2153  *                     mutually exclusive, only one of these two should
2154  *                     be specified. Enabling both fields will have
2155  *                     undetermined results.
2156  *
2157  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
2158  *                     to be made immediately.
2159  *
2160  *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
2161  *                     heartbeat delayis to be set to the value of 0
2162  *                     milliseconds.
2163  *
2164  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
2165  *                     discovery upon the specified address. Note that
2166  *                     if the address feild is empty then all addresses
2167  *                     on the association are effected.
2168  *
2169  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
2170  *                     discovery upon the specified address. Note that
2171  *                     if the address feild is empty then all addresses
2172  *                     on the association are effected. Not also that
2173  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
2174  *                     exclusive. Enabling both will have undetermined
2175  *                     results.
2176  *
2177  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
2178  *                     on delayed sack. The time specified in spp_sackdelay
2179  *                     is used to specify the sack delay for this address. Note
2180  *                     that if spp_address is empty then all addresses will
2181  *                     enable delayed sack and take on the sack delay
2182  *                     value specified in spp_sackdelay.
2183  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
2184  *                     off delayed sack. If the spp_address field is blank then
2185  *                     delayed sack is disabled for the entire association. Note
2186  *                     also that this field is mutually exclusive to
2187  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
2188  *                     results.
2189  */
2190 static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
2191 				       struct sctp_transport   *trans,
2192 				       struct sctp_association *asoc,
2193 				       struct sctp_sock        *sp,
2194 				       int                      hb_change,
2195 				       int                      pmtud_change,
2196 				       int                      sackdelay_change)
2197 {
2198 	int error;
2199 
2200 	if (params->spp_flags & SPP_HB_DEMAND && trans) {
2201 		error = sctp_primitive_REQUESTHEARTBEAT (trans->asoc, trans);
2202 		if (error)
2203 			return error;
2204 	}
2205 
2206 	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
2207 	 * this field is ignored.  Note also that a value of zero indicates
2208 	 * the current setting should be left unchanged.
2209 	 */
2210 	if (params->spp_flags & SPP_HB_ENABLE) {
2211 
2212 		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
2213 		 * set.  This lets us use 0 value when this flag
2214 		 * is set.
2215 		 */
2216 		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
2217 			params->spp_hbinterval = 0;
2218 
2219 		if (params->spp_hbinterval ||
2220 		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
2221 			if (trans) {
2222 				trans->hbinterval =
2223 				    msecs_to_jiffies(params->spp_hbinterval);
2224 			} else if (asoc) {
2225 				asoc->hbinterval =
2226 				    msecs_to_jiffies(params->spp_hbinterval);
2227 			} else {
2228 				sp->hbinterval = params->spp_hbinterval;
2229 			}
2230 		}
2231 	}
2232 
2233 	if (hb_change) {
2234 		if (trans) {
2235 			trans->param_flags =
2236 				(trans->param_flags & ~SPP_HB) | hb_change;
2237 		} else if (asoc) {
2238 			asoc->param_flags =
2239 				(asoc->param_flags & ~SPP_HB) | hb_change;
2240 		} else {
2241 			sp->param_flags =
2242 				(sp->param_flags & ~SPP_HB) | hb_change;
2243 		}
2244 	}
2245 
2246 	/* When Path MTU discovery is disabled the value specified here will
2247 	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
2248 	 * include the flag SPP_PMTUD_DISABLE for this field to have any
2249 	 * effect).
2250 	 */
2251 	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
2252 		if (trans) {
2253 			trans->pathmtu = params->spp_pathmtu;
2254 			sctp_assoc_sync_pmtu(asoc);
2255 		} else if (asoc) {
2256 			asoc->pathmtu = params->spp_pathmtu;
2257 			sctp_frag_point(asoc, params->spp_pathmtu);
2258 		} else {
2259 			sp->pathmtu = params->spp_pathmtu;
2260 		}
2261 	}
2262 
2263 	if (pmtud_change) {
2264 		if (trans) {
2265 			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
2266 				(params->spp_flags & SPP_PMTUD_ENABLE);
2267 			trans->param_flags =
2268 				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
2269 			if (update) {
2270 				sctp_transport_pmtu(trans);
2271 				sctp_assoc_sync_pmtu(asoc);
2272 			}
2273 		} else if (asoc) {
2274 			asoc->param_flags =
2275 				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
2276 		} else {
2277 			sp->param_flags =
2278 				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
2279 		}
2280 	}
2281 
2282 	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
2283 	 * value of this field is ignored.  Note also that a value of zero
2284 	 * indicates the current setting should be left unchanged.
2285 	 */
2286 	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
2287 		if (trans) {
2288 			trans->sackdelay =
2289 				msecs_to_jiffies(params->spp_sackdelay);
2290 		} else if (asoc) {
2291 			asoc->sackdelay =
2292 				msecs_to_jiffies(params->spp_sackdelay);
2293 		} else {
2294 			sp->sackdelay = params->spp_sackdelay;
2295 		}
2296 	}
2297 
2298 	if (sackdelay_change) {
2299 		if (trans) {
2300 			trans->param_flags =
2301 				(trans->param_flags & ~SPP_SACKDELAY) |
2302 				sackdelay_change;
2303 		} else if (asoc) {
2304 			asoc->param_flags =
2305 				(asoc->param_flags & ~SPP_SACKDELAY) |
2306 				sackdelay_change;
2307 		} else {
2308 			sp->param_flags =
2309 				(sp->param_flags & ~SPP_SACKDELAY) |
2310 				sackdelay_change;
2311 		}
2312 	}
2313 
2314 	/* Note that unless the spp_flag is set to SPP_PMTUD_ENABLE the value
2315 	 * of this field is ignored.  Note also that a value of zero
2316 	 * indicates the current setting should be left unchanged.
2317 	 */
2318 	if ((params->spp_flags & SPP_PMTUD_ENABLE) && params->spp_pathmaxrxt) {
2319 		if (trans) {
2320 			trans->pathmaxrxt = params->spp_pathmaxrxt;
2321 		} else if (asoc) {
2322 			asoc->pathmaxrxt = params->spp_pathmaxrxt;
2323 		} else {
2324 			sp->pathmaxrxt = params->spp_pathmaxrxt;
2325 		}
2326 	}
2327 
2328 	return 0;
2329 }
2330 
2331 static int sctp_setsockopt_peer_addr_params(struct sock *sk,
2332 					    char __user *optval,
2333 					    unsigned int optlen)
2334 {
2335 	struct sctp_paddrparams  params;
2336 	struct sctp_transport   *trans = NULL;
2337 	struct sctp_association *asoc = NULL;
2338 	struct sctp_sock        *sp = sctp_sk(sk);
2339 	int error;
2340 	int hb_change, pmtud_change, sackdelay_change;
2341 
2342 	if (optlen != sizeof(struct sctp_paddrparams))
2343 		return - EINVAL;
2344 
2345 	if (copy_from_user(&params, optval, optlen))
2346 		return -EFAULT;
2347 
2348 	/* Validate flags and value parameters. */
2349 	hb_change        = params.spp_flags & SPP_HB;
2350 	pmtud_change     = params.spp_flags & SPP_PMTUD;
2351 	sackdelay_change = params.spp_flags & SPP_SACKDELAY;
2352 
2353 	if (hb_change        == SPP_HB ||
2354 	    pmtud_change     == SPP_PMTUD ||
2355 	    sackdelay_change == SPP_SACKDELAY ||
2356 	    params.spp_sackdelay > 500 ||
2357 	    (params.spp_pathmtu
2358 	    && params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
2359 		return -EINVAL;
2360 
2361 	/* If an address other than INADDR_ANY is specified, and
2362 	 * no transport is found, then the request is invalid.
2363 	 */
2364 	if (!sctp_is_any(sk, ( union sctp_addr *)&params.spp_address)) {
2365 		trans = sctp_addr_id2transport(sk, &params.spp_address,
2366 					       params.spp_assoc_id);
2367 		if (!trans)
2368 			return -EINVAL;
2369 	}
2370 
2371 	/* Get association, if assoc_id != 0 and the socket is a one
2372 	 * to many style socket, and an association was not found, then
2373 	 * the id was invalid.
2374 	 */
2375 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
2376 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
2377 		return -EINVAL;
2378 
2379 	/* Heartbeat demand can only be sent on a transport or
2380 	 * association, but not a socket.
2381 	 */
2382 	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
2383 		return -EINVAL;
2384 
2385 	/* Process parameters. */
2386 	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2387 					    hb_change, pmtud_change,
2388 					    sackdelay_change);
2389 
2390 	if (error)
2391 		return error;
2392 
2393 	/* If changes are for association, also apply parameters to each
2394 	 * transport.
2395 	 */
2396 	if (!trans && asoc) {
2397 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2398 				transports) {
2399 			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2400 						    hb_change, pmtud_change,
2401 						    sackdelay_change);
2402 		}
2403 	}
2404 
2405 	return 0;
2406 }
2407 
2408 /*
2409  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
2410  *
2411  * This option will effect the way delayed acks are performed.  This
2412  * option allows you to get or set the delayed ack time, in
2413  * milliseconds.  It also allows changing the delayed ack frequency.
2414  * Changing the frequency to 1 disables the delayed sack algorithm.  If
2415  * the assoc_id is 0, then this sets or gets the endpoints default
2416  * values.  If the assoc_id field is non-zero, then the set or get
2417  * effects the specified association for the one to many model (the
2418  * assoc_id field is ignored by the one to one model).  Note that if
2419  * sack_delay or sack_freq are 0 when setting this option, then the
2420  * current values will remain unchanged.
2421  *
2422  * struct sctp_sack_info {
2423  *     sctp_assoc_t            sack_assoc_id;
2424  *     uint32_t                sack_delay;
2425  *     uint32_t                sack_freq;
2426  * };
2427  *
2428  * sack_assoc_id -  This parameter, indicates which association the user
2429  *    is performing an action upon.  Note that if this field's value is
2430  *    zero then the endpoints default value is changed (effecting future
2431  *    associations only).
2432  *
2433  * sack_delay -  This parameter contains the number of milliseconds that
2434  *    the user is requesting the delayed ACK timer be set to.  Note that
2435  *    this value is defined in the standard to be between 200 and 500
2436  *    milliseconds.
2437  *
2438  * sack_freq -  This parameter contains the number of packets that must
2439  *    be received before a sack is sent without waiting for the delay
2440  *    timer to expire.  The default value for this is 2, setting this
2441  *    value to 1 will disable the delayed sack algorithm.
2442  */
2443 
2444 static int sctp_setsockopt_delayed_ack(struct sock *sk,
2445 				       char __user *optval, unsigned int optlen)
2446 {
2447 	struct sctp_sack_info    params;
2448 	struct sctp_transport   *trans = NULL;
2449 	struct sctp_association *asoc = NULL;
2450 	struct sctp_sock        *sp = sctp_sk(sk);
2451 
2452 	if (optlen == sizeof(struct sctp_sack_info)) {
2453 		if (copy_from_user(&params, optval, optlen))
2454 			return -EFAULT;
2455 
2456 		if (params.sack_delay == 0 && params.sack_freq == 0)
2457 			return 0;
2458 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
2459 		printk(KERN_WARNING "SCTP: Use of struct sctp_assoc_value "
2460 		       "in delayed_ack socket option deprecated\n");
2461 		printk(KERN_WARNING "SCTP: Use struct sctp_sack_info instead\n");
2462 		if (copy_from_user(&params, optval, optlen))
2463 			return -EFAULT;
2464 
2465 		if (params.sack_delay == 0)
2466 			params.sack_freq = 1;
2467 		else
2468 			params.sack_freq = 0;
2469 	} else
2470 		return - EINVAL;
2471 
2472 	/* Validate value parameter. */
2473 	if (params.sack_delay > 500)
2474 		return -EINVAL;
2475 
2476 	/* Get association, if sack_assoc_id != 0 and the socket is a one
2477 	 * to many style socket, and an association was not found, then
2478 	 * the id was invalid.
2479 	 */
2480 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
2481 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
2482 		return -EINVAL;
2483 
2484 	if (params.sack_delay) {
2485 		if (asoc) {
2486 			asoc->sackdelay =
2487 				msecs_to_jiffies(params.sack_delay);
2488 			asoc->param_flags =
2489 				(asoc->param_flags & ~SPP_SACKDELAY) |
2490 				SPP_SACKDELAY_ENABLE;
2491 		} else {
2492 			sp->sackdelay = params.sack_delay;
2493 			sp->param_flags =
2494 				(sp->param_flags & ~SPP_SACKDELAY) |
2495 				SPP_SACKDELAY_ENABLE;
2496 		}
2497 	}
2498 
2499 	if (params.sack_freq == 1) {
2500 		if (asoc) {
2501 			asoc->param_flags =
2502 				(asoc->param_flags & ~SPP_SACKDELAY) |
2503 				SPP_SACKDELAY_DISABLE;
2504 		} else {
2505 			sp->param_flags =
2506 				(sp->param_flags & ~SPP_SACKDELAY) |
2507 				SPP_SACKDELAY_DISABLE;
2508 		}
2509 	} else if (params.sack_freq > 1) {
2510 		if (asoc) {
2511 			asoc->sackfreq = params.sack_freq;
2512 			asoc->param_flags =
2513 				(asoc->param_flags & ~SPP_SACKDELAY) |
2514 				SPP_SACKDELAY_ENABLE;
2515 		} else {
2516 			sp->sackfreq = params.sack_freq;
2517 			sp->param_flags =
2518 				(sp->param_flags & ~SPP_SACKDELAY) |
2519 				SPP_SACKDELAY_ENABLE;
2520 		}
2521 	}
2522 
2523 	/* If change is for association, also apply to each transport. */
2524 	if (asoc) {
2525 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2526 				transports) {
2527 			if (params.sack_delay) {
2528 				trans->sackdelay =
2529 					msecs_to_jiffies(params.sack_delay);
2530 				trans->param_flags =
2531 					(trans->param_flags & ~SPP_SACKDELAY) |
2532 					SPP_SACKDELAY_ENABLE;
2533 			}
2534 			if (params.sack_freq == 1) {
2535 				trans->param_flags =
2536 					(trans->param_flags & ~SPP_SACKDELAY) |
2537 					SPP_SACKDELAY_DISABLE;
2538 			} else if (params.sack_freq > 1) {
2539 				trans->sackfreq = params.sack_freq;
2540 				trans->param_flags =
2541 					(trans->param_flags & ~SPP_SACKDELAY) |
2542 					SPP_SACKDELAY_ENABLE;
2543 			}
2544 		}
2545 	}
2546 
2547 	return 0;
2548 }
2549 
2550 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
2551  *
2552  * Applications can specify protocol parameters for the default association
2553  * initialization.  The option name argument to setsockopt() and getsockopt()
2554  * is SCTP_INITMSG.
2555  *
2556  * Setting initialization parameters is effective only on an unconnected
2557  * socket (for UDP-style sockets only future associations are effected
2558  * by the change).  With TCP-style sockets, this option is inherited by
2559  * sockets derived from a listener socket.
2560  */
2561 static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, unsigned int optlen)
2562 {
2563 	struct sctp_initmsg sinit;
2564 	struct sctp_sock *sp = sctp_sk(sk);
2565 
2566 	if (optlen != sizeof(struct sctp_initmsg))
2567 		return -EINVAL;
2568 	if (copy_from_user(&sinit, optval, optlen))
2569 		return -EFAULT;
2570 
2571 	if (sinit.sinit_num_ostreams)
2572 		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
2573 	if (sinit.sinit_max_instreams)
2574 		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
2575 	if (sinit.sinit_max_attempts)
2576 		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
2577 	if (sinit.sinit_max_init_timeo)
2578 		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
2579 
2580 	return 0;
2581 }
2582 
2583 /*
2584  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
2585  *
2586  *   Applications that wish to use the sendto() system call may wish to
2587  *   specify a default set of parameters that would normally be supplied
2588  *   through the inclusion of ancillary data.  This socket option allows
2589  *   such an application to set the default sctp_sndrcvinfo structure.
2590  *   The application that wishes to use this socket option simply passes
2591  *   in to this call the sctp_sndrcvinfo structure defined in Section
2592  *   5.2.2) The input parameters accepted by this call include
2593  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
2594  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
2595  *   to this call if the caller is using the UDP model.
2596  */
2597 static int sctp_setsockopt_default_send_param(struct sock *sk,
2598 					      char __user *optval,
2599 					      unsigned int optlen)
2600 {
2601 	struct sctp_sndrcvinfo info;
2602 	struct sctp_association *asoc;
2603 	struct sctp_sock *sp = sctp_sk(sk);
2604 
2605 	if (optlen != sizeof(struct sctp_sndrcvinfo))
2606 		return -EINVAL;
2607 	if (copy_from_user(&info, optval, optlen))
2608 		return -EFAULT;
2609 
2610 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
2611 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
2612 		return -EINVAL;
2613 
2614 	if (asoc) {
2615 		asoc->default_stream = info.sinfo_stream;
2616 		asoc->default_flags = info.sinfo_flags;
2617 		asoc->default_ppid = info.sinfo_ppid;
2618 		asoc->default_context = info.sinfo_context;
2619 		asoc->default_timetolive = info.sinfo_timetolive;
2620 	} else {
2621 		sp->default_stream = info.sinfo_stream;
2622 		sp->default_flags = info.sinfo_flags;
2623 		sp->default_ppid = info.sinfo_ppid;
2624 		sp->default_context = info.sinfo_context;
2625 		sp->default_timetolive = info.sinfo_timetolive;
2626 	}
2627 
2628 	return 0;
2629 }
2630 
2631 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
2632  *
2633  * Requests that the local SCTP stack use the enclosed peer address as
2634  * the association primary.  The enclosed address must be one of the
2635  * association peer's addresses.
2636  */
2637 static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
2638 					unsigned int optlen)
2639 {
2640 	struct sctp_prim prim;
2641 	struct sctp_transport *trans;
2642 
2643 	if (optlen != sizeof(struct sctp_prim))
2644 		return -EINVAL;
2645 
2646 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
2647 		return -EFAULT;
2648 
2649 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
2650 	if (!trans)
2651 		return -EINVAL;
2652 
2653 	sctp_assoc_set_primary(trans->asoc, trans);
2654 
2655 	return 0;
2656 }
2657 
2658 /*
2659  * 7.1.5 SCTP_NODELAY
2660  *
2661  * Turn on/off any Nagle-like algorithm.  This means that packets are
2662  * generally sent as soon as possible and no unnecessary delays are
2663  * introduced, at the cost of more packets in the network.  Expects an
2664  *  integer boolean flag.
2665  */
2666 static int sctp_setsockopt_nodelay(struct sock *sk, char __user *optval,
2667 				   unsigned int optlen)
2668 {
2669 	int val;
2670 
2671 	if (optlen < sizeof(int))
2672 		return -EINVAL;
2673 	if (get_user(val, (int __user *)optval))
2674 		return -EFAULT;
2675 
2676 	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
2677 	return 0;
2678 }
2679 
2680 /*
2681  *
2682  * 7.1.1 SCTP_RTOINFO
2683  *
2684  * The protocol parameters used to initialize and bound retransmission
2685  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
2686  * and modify these parameters.
2687  * All parameters are time values, in milliseconds.  A value of 0, when
2688  * modifying the parameters, indicates that the current value should not
2689  * be changed.
2690  *
2691  */
2692 static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, unsigned int optlen)
2693 {
2694 	struct sctp_rtoinfo rtoinfo;
2695 	struct sctp_association *asoc;
2696 
2697 	if (optlen != sizeof (struct sctp_rtoinfo))
2698 		return -EINVAL;
2699 
2700 	if (copy_from_user(&rtoinfo, optval, optlen))
2701 		return -EFAULT;
2702 
2703 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
2704 
2705 	/* Set the values to the specific association */
2706 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
2707 		return -EINVAL;
2708 
2709 	if (asoc) {
2710 		if (rtoinfo.srto_initial != 0)
2711 			asoc->rto_initial =
2712 				msecs_to_jiffies(rtoinfo.srto_initial);
2713 		if (rtoinfo.srto_max != 0)
2714 			asoc->rto_max = msecs_to_jiffies(rtoinfo.srto_max);
2715 		if (rtoinfo.srto_min != 0)
2716 			asoc->rto_min = msecs_to_jiffies(rtoinfo.srto_min);
2717 	} else {
2718 		/* If there is no association or the association-id = 0
2719 		 * set the values to the endpoint.
2720 		 */
2721 		struct sctp_sock *sp = sctp_sk(sk);
2722 
2723 		if (rtoinfo.srto_initial != 0)
2724 			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
2725 		if (rtoinfo.srto_max != 0)
2726 			sp->rtoinfo.srto_max = rtoinfo.srto_max;
2727 		if (rtoinfo.srto_min != 0)
2728 			sp->rtoinfo.srto_min = rtoinfo.srto_min;
2729 	}
2730 
2731 	return 0;
2732 }
2733 
2734 /*
2735  *
2736  * 7.1.2 SCTP_ASSOCINFO
2737  *
2738  * This option is used to tune the maximum retransmission attempts
2739  * of the association.
2740  * Returns an error if the new association retransmission value is
2741  * greater than the sum of the retransmission value  of the peer.
2742  * See [SCTP] for more information.
2743  *
2744  */
2745 static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, unsigned int optlen)
2746 {
2747 
2748 	struct sctp_assocparams assocparams;
2749 	struct sctp_association *asoc;
2750 
2751 	if (optlen != sizeof(struct sctp_assocparams))
2752 		return -EINVAL;
2753 	if (copy_from_user(&assocparams, optval, optlen))
2754 		return -EFAULT;
2755 
2756 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
2757 
2758 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
2759 		return -EINVAL;
2760 
2761 	/* Set the values to the specific association */
2762 	if (asoc) {
2763 		if (assocparams.sasoc_asocmaxrxt != 0) {
2764 			__u32 path_sum = 0;
2765 			int   paths = 0;
2766 			struct sctp_transport *peer_addr;
2767 
2768 			list_for_each_entry(peer_addr, &asoc->peer.transport_addr_list,
2769 					transports) {
2770 				path_sum += peer_addr->pathmaxrxt;
2771 				paths++;
2772 			}
2773 
2774 			/* Only validate asocmaxrxt if we have more than
2775 			 * one path/transport.  We do this because path
2776 			 * retransmissions are only counted when we have more
2777 			 * then one path.
2778 			 */
2779 			if (paths > 1 &&
2780 			    assocparams.sasoc_asocmaxrxt > path_sum)
2781 				return -EINVAL;
2782 
2783 			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
2784 		}
2785 
2786 		if (assocparams.sasoc_cookie_life != 0) {
2787 			asoc->cookie_life.tv_sec =
2788 					assocparams.sasoc_cookie_life / 1000;
2789 			asoc->cookie_life.tv_usec =
2790 					(assocparams.sasoc_cookie_life % 1000)
2791 					* 1000;
2792 		}
2793 	} else {
2794 		/* Set the values to the endpoint */
2795 		struct sctp_sock *sp = sctp_sk(sk);
2796 
2797 		if (assocparams.sasoc_asocmaxrxt != 0)
2798 			sp->assocparams.sasoc_asocmaxrxt =
2799 						assocparams.sasoc_asocmaxrxt;
2800 		if (assocparams.sasoc_cookie_life != 0)
2801 			sp->assocparams.sasoc_cookie_life =
2802 						assocparams.sasoc_cookie_life;
2803 	}
2804 	return 0;
2805 }
2806 
2807 /*
2808  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
2809  *
2810  * This socket option is a boolean flag which turns on or off mapped V4
2811  * addresses.  If this option is turned on and the socket is type
2812  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
2813  * If this option is turned off, then no mapping will be done of V4
2814  * addresses and a user will receive both PF_INET6 and PF_INET type
2815  * addresses on the socket.
2816  */
2817 static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsigned int optlen)
2818 {
2819 	int val;
2820 	struct sctp_sock *sp = sctp_sk(sk);
2821 
2822 	if (optlen < sizeof(int))
2823 		return -EINVAL;
2824 	if (get_user(val, (int __user *)optval))
2825 		return -EFAULT;
2826 	if (val)
2827 		sp->v4mapped = 1;
2828 	else
2829 		sp->v4mapped = 0;
2830 
2831 	return 0;
2832 }
2833 
2834 /*
2835  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
2836  * This option will get or set the maximum size to put in any outgoing
2837  * SCTP DATA chunk.  If a message is larger than this size it will be
2838  * fragmented by SCTP into the specified size.  Note that the underlying
2839  * SCTP implementation may fragment into smaller sized chunks when the
2840  * PMTU of the underlying association is smaller than the value set by
2841  * the user.  The default value for this option is '0' which indicates
2842  * the user is NOT limiting fragmentation and only the PMTU will effect
2843  * SCTP's choice of DATA chunk size.  Note also that values set larger
2844  * than the maximum size of an IP datagram will effectively let SCTP
2845  * control fragmentation (i.e. the same as setting this option to 0).
2846  *
2847  * The following structure is used to access and modify this parameter:
2848  *
2849  * struct sctp_assoc_value {
2850  *   sctp_assoc_t assoc_id;
2851  *   uint32_t assoc_value;
2852  * };
2853  *
2854  * assoc_id:  This parameter is ignored for one-to-one style sockets.
2855  *    For one-to-many style sockets this parameter indicates which
2856  *    association the user is performing an action upon.  Note that if
2857  *    this field's value is zero then the endpoints default value is
2858  *    changed (effecting future associations only).
2859  * assoc_value:  This parameter specifies the maximum size in bytes.
2860  */
2861 static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
2862 {
2863 	struct sctp_assoc_value params;
2864 	struct sctp_association *asoc;
2865 	struct sctp_sock *sp = sctp_sk(sk);
2866 	int val;
2867 
2868 	if (optlen == sizeof(int)) {
2869 		printk(KERN_WARNING
2870 		   "SCTP: Use of int in maxseg socket option deprecated\n");
2871 		printk(KERN_WARNING
2872 		   "SCTP: Use struct sctp_assoc_value instead\n");
2873 		if (copy_from_user(&val, optval, optlen))
2874 			return -EFAULT;
2875 		params.assoc_id = 0;
2876 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
2877 		if (copy_from_user(&params, optval, optlen))
2878 			return -EFAULT;
2879 		val = params.assoc_value;
2880 	} else
2881 		return -EINVAL;
2882 
2883 	if ((val != 0) && ((val < 8) || (val > SCTP_MAX_CHUNK_LEN)))
2884 		return -EINVAL;
2885 
2886 	asoc = sctp_id2assoc(sk, params.assoc_id);
2887 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
2888 		return -EINVAL;
2889 
2890 	if (asoc) {
2891 		if (val == 0) {
2892 			val = asoc->pathmtu;
2893 			val -= sp->pf->af->net_header_len;
2894 			val -= sizeof(struct sctphdr) +
2895 					sizeof(struct sctp_data_chunk);
2896 		}
2897 		asoc->user_frag = val;
2898 		asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
2899 	} else {
2900 		sp->user_frag = val;
2901 	}
2902 
2903 	return 0;
2904 }
2905 
2906 
2907 /*
2908  *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
2909  *
2910  *   Requests that the peer mark the enclosed address as the association
2911  *   primary. The enclosed address must be one of the association's
2912  *   locally bound addresses. The following structure is used to make a
2913  *   set primary request:
2914  */
2915 static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
2916 					     unsigned int optlen)
2917 {
2918 	struct sctp_sock	*sp;
2919 	struct sctp_endpoint	*ep;
2920 	struct sctp_association	*asoc = NULL;
2921 	struct sctp_setpeerprim	prim;
2922 	struct sctp_chunk	*chunk;
2923 	int 			err;
2924 
2925 	sp = sctp_sk(sk);
2926 	ep = sp->ep;
2927 
2928 	if (!sctp_addip_enable)
2929 		return -EPERM;
2930 
2931 	if (optlen != sizeof(struct sctp_setpeerprim))
2932 		return -EINVAL;
2933 
2934 	if (copy_from_user(&prim, optval, optlen))
2935 		return -EFAULT;
2936 
2937 	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
2938 	if (!asoc)
2939 		return -EINVAL;
2940 
2941 	if (!asoc->peer.asconf_capable)
2942 		return -EPERM;
2943 
2944 	if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
2945 		return -EPERM;
2946 
2947 	if (!sctp_state(asoc, ESTABLISHED))
2948 		return -ENOTCONN;
2949 
2950 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
2951 		return -EADDRNOTAVAIL;
2952 
2953 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
2954 	chunk = sctp_make_asconf_set_prim(asoc,
2955 					  (union sctp_addr *)&prim.sspp_addr);
2956 	if (!chunk)
2957 		return -ENOMEM;
2958 
2959 	err = sctp_send_asconf(asoc, chunk);
2960 
2961 	SCTP_DEBUG_PRINTK("We set peer primary addr primitively.\n");
2962 
2963 	return err;
2964 }
2965 
2966 static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
2967 					    unsigned int optlen)
2968 {
2969 	struct sctp_setadaptation adaptation;
2970 
2971 	if (optlen != sizeof(struct sctp_setadaptation))
2972 		return -EINVAL;
2973 	if (copy_from_user(&adaptation, optval, optlen))
2974 		return -EFAULT;
2975 
2976 	sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
2977 
2978 	return 0;
2979 }
2980 
2981 /*
2982  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
2983  *
2984  * The context field in the sctp_sndrcvinfo structure is normally only
2985  * used when a failed message is retrieved holding the value that was
2986  * sent down on the actual send call.  This option allows the setting of
2987  * a default context on an association basis that will be received on
2988  * reading messages from the peer.  This is especially helpful in the
2989  * one-2-many model for an application to keep some reference to an
2990  * internal state machine that is processing messages on the
2991  * association.  Note that the setting of this value only effects
2992  * received messages from the peer and does not effect the value that is
2993  * saved with outbound messages.
2994  */
2995 static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
2996 				   unsigned int optlen)
2997 {
2998 	struct sctp_assoc_value params;
2999 	struct sctp_sock *sp;
3000 	struct sctp_association *asoc;
3001 
3002 	if (optlen != sizeof(struct sctp_assoc_value))
3003 		return -EINVAL;
3004 	if (copy_from_user(&params, optval, optlen))
3005 		return -EFAULT;
3006 
3007 	sp = sctp_sk(sk);
3008 
3009 	if (params.assoc_id != 0) {
3010 		asoc = sctp_id2assoc(sk, params.assoc_id);
3011 		if (!asoc)
3012 			return -EINVAL;
3013 		asoc->default_rcv_context = params.assoc_value;
3014 	} else {
3015 		sp->default_rcv_context = params.assoc_value;
3016 	}
3017 
3018 	return 0;
3019 }
3020 
3021 /*
3022  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
3023  *
3024  * This options will at a minimum specify if the implementation is doing
3025  * fragmented interleave.  Fragmented interleave, for a one to many
3026  * socket, is when subsequent calls to receive a message may return
3027  * parts of messages from different associations.  Some implementations
3028  * may allow you to turn this value on or off.  If so, when turned off,
3029  * no fragment interleave will occur (which will cause a head of line
3030  * blocking amongst multiple associations sharing the same one to many
3031  * socket).  When this option is turned on, then each receive call may
3032  * come from a different association (thus the user must receive data
3033  * with the extended calls (e.g. sctp_recvmsg) to keep track of which
3034  * association each receive belongs to.
3035  *
3036  * This option takes a boolean value.  A non-zero value indicates that
3037  * fragmented interleave is on.  A value of zero indicates that
3038  * fragmented interleave is off.
3039  *
3040  * Note that it is important that an implementation that allows this
3041  * option to be turned on, have it off by default.  Otherwise an unaware
3042  * application using the one to many model may become confused and act
3043  * incorrectly.
3044  */
3045 static int sctp_setsockopt_fragment_interleave(struct sock *sk,
3046 					       char __user *optval,
3047 					       unsigned int optlen)
3048 {
3049 	int val;
3050 
3051 	if (optlen != sizeof(int))
3052 		return -EINVAL;
3053 	if (get_user(val, (int __user *)optval))
3054 		return -EFAULT;
3055 
3056 	sctp_sk(sk)->frag_interleave = (val == 0) ? 0 : 1;
3057 
3058 	return 0;
3059 }
3060 
3061 /*
3062  * 8.1.21.  Set or Get the SCTP Partial Delivery Point
3063  *       (SCTP_PARTIAL_DELIVERY_POINT)
3064  *
3065  * This option will set or get the SCTP partial delivery point.  This
3066  * point is the size of a message where the partial delivery API will be
3067  * invoked to help free up rwnd space for the peer.  Setting this to a
3068  * lower value will cause partial deliveries to happen more often.  The
3069  * calls argument is an integer that sets or gets the partial delivery
3070  * point.  Note also that the call will fail if the user attempts to set
3071  * this value larger than the socket receive buffer size.
3072  *
3073  * Note that any single message having a length smaller than or equal to
3074  * the SCTP partial delivery point will be delivered in one single read
3075  * call as long as the user provided buffer is large enough to hold the
3076  * message.
3077  */
3078 static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
3079 						  char __user *optval,
3080 						  unsigned int optlen)
3081 {
3082 	u32 val;
3083 
3084 	if (optlen != sizeof(u32))
3085 		return -EINVAL;
3086 	if (get_user(val, (int __user *)optval))
3087 		return -EFAULT;
3088 
3089 	/* Note: We double the receive buffer from what the user sets
3090 	 * it to be, also initial rwnd is based on rcvbuf/2.
3091 	 */
3092 	if (val > (sk->sk_rcvbuf >> 1))
3093 		return -EINVAL;
3094 
3095 	sctp_sk(sk)->pd_point = val;
3096 
3097 	return 0; /* is this the right error code? */
3098 }
3099 
3100 /*
3101  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
3102  *
3103  * This option will allow a user to change the maximum burst of packets
3104  * that can be emitted by this association.  Note that the default value
3105  * is 4, and some implementations may restrict this setting so that it
3106  * can only be lowered.
3107  *
3108  * NOTE: This text doesn't seem right.  Do this on a socket basis with
3109  * future associations inheriting the socket value.
3110  */
3111 static int sctp_setsockopt_maxburst(struct sock *sk,
3112 				    char __user *optval,
3113 				    unsigned int optlen)
3114 {
3115 	struct sctp_assoc_value params;
3116 	struct sctp_sock *sp;
3117 	struct sctp_association *asoc;
3118 	int val;
3119 	int assoc_id = 0;
3120 
3121 	if (optlen == sizeof(int)) {
3122 		printk(KERN_WARNING
3123 		   "SCTP: Use of int in max_burst socket option deprecated\n");
3124 		printk(KERN_WARNING
3125 		   "SCTP: Use struct sctp_assoc_value instead\n");
3126 		if (copy_from_user(&val, optval, optlen))
3127 			return -EFAULT;
3128 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
3129 		if (copy_from_user(&params, optval, optlen))
3130 			return -EFAULT;
3131 		val = params.assoc_value;
3132 		assoc_id = params.assoc_id;
3133 	} else
3134 		return -EINVAL;
3135 
3136 	sp = sctp_sk(sk);
3137 
3138 	if (assoc_id != 0) {
3139 		asoc = sctp_id2assoc(sk, assoc_id);
3140 		if (!asoc)
3141 			return -EINVAL;
3142 		asoc->max_burst = val;
3143 	} else
3144 		sp->max_burst = val;
3145 
3146 	return 0;
3147 }
3148 
3149 /*
3150  * 7.1.18.  Add a chunk that must be authenticated (SCTP_AUTH_CHUNK)
3151  *
3152  * This set option adds a chunk type that the user is requesting to be
3153  * received only in an authenticated way.  Changes to the list of chunks
3154  * will only effect future associations on the socket.
3155  */
3156 static int sctp_setsockopt_auth_chunk(struct sock *sk,
3157 				      char __user *optval,
3158 				      unsigned int optlen)
3159 {
3160 	struct sctp_authchunk val;
3161 
3162 	if (!sctp_auth_enable)
3163 		return -EACCES;
3164 
3165 	if (optlen != sizeof(struct sctp_authchunk))
3166 		return -EINVAL;
3167 	if (copy_from_user(&val, optval, optlen))
3168 		return -EFAULT;
3169 
3170 	switch (val.sauth_chunk) {
3171 		case SCTP_CID_INIT:
3172 		case SCTP_CID_INIT_ACK:
3173 		case SCTP_CID_SHUTDOWN_COMPLETE:
3174 		case SCTP_CID_AUTH:
3175 			return -EINVAL;
3176 	}
3177 
3178 	/* add this chunk id to the endpoint */
3179 	return sctp_auth_ep_add_chunkid(sctp_sk(sk)->ep, val.sauth_chunk);
3180 }
3181 
3182 /*
3183  * 7.1.19.  Get or set the list of supported HMAC Identifiers (SCTP_HMAC_IDENT)
3184  *
3185  * This option gets or sets the list of HMAC algorithms that the local
3186  * endpoint requires the peer to use.
3187  */
3188 static int sctp_setsockopt_hmac_ident(struct sock *sk,
3189 				      char __user *optval,
3190 				      unsigned int optlen)
3191 {
3192 	struct sctp_hmacalgo *hmacs;
3193 	u32 idents;
3194 	int err;
3195 
3196 	if (!sctp_auth_enable)
3197 		return -EACCES;
3198 
3199 	if (optlen < sizeof(struct sctp_hmacalgo))
3200 		return -EINVAL;
3201 
3202 	hmacs = kmalloc(optlen, GFP_KERNEL);
3203 	if (!hmacs)
3204 		return -ENOMEM;
3205 
3206 	if (copy_from_user(hmacs, optval, optlen)) {
3207 		err = -EFAULT;
3208 		goto out;
3209 	}
3210 
3211 	idents = hmacs->shmac_num_idents;
3212 	if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS ||
3213 	    (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo))) {
3214 		err = -EINVAL;
3215 		goto out;
3216 	}
3217 
3218 	err = sctp_auth_ep_set_hmacs(sctp_sk(sk)->ep, hmacs);
3219 out:
3220 	kfree(hmacs);
3221 	return err;
3222 }
3223 
3224 /*
3225  * 7.1.20.  Set a shared key (SCTP_AUTH_KEY)
3226  *
3227  * This option will set a shared secret key which is used to build an
3228  * association shared key.
3229  */
3230 static int sctp_setsockopt_auth_key(struct sock *sk,
3231 				    char __user *optval,
3232 				    unsigned int optlen)
3233 {
3234 	struct sctp_authkey *authkey;
3235 	struct sctp_association *asoc;
3236 	int ret;
3237 
3238 	if (!sctp_auth_enable)
3239 		return -EACCES;
3240 
3241 	if (optlen <= sizeof(struct sctp_authkey))
3242 		return -EINVAL;
3243 
3244 	authkey = kmalloc(optlen, GFP_KERNEL);
3245 	if (!authkey)
3246 		return -ENOMEM;
3247 
3248 	if (copy_from_user(authkey, optval, optlen)) {
3249 		ret = -EFAULT;
3250 		goto out;
3251 	}
3252 
3253 	if (authkey->sca_keylength > optlen - sizeof(struct sctp_authkey)) {
3254 		ret = -EINVAL;
3255 		goto out;
3256 	}
3257 
3258 	asoc = sctp_id2assoc(sk, authkey->sca_assoc_id);
3259 	if (!asoc && authkey->sca_assoc_id && sctp_style(sk, UDP)) {
3260 		ret = -EINVAL;
3261 		goto out;
3262 	}
3263 
3264 	ret = sctp_auth_set_key(sctp_sk(sk)->ep, asoc, authkey);
3265 out:
3266 	kfree(authkey);
3267 	return ret;
3268 }
3269 
3270 /*
3271  * 7.1.21.  Get or set the active shared key (SCTP_AUTH_ACTIVE_KEY)
3272  *
3273  * This option will get or set the active shared key to be used to build
3274  * the association shared key.
3275  */
3276 static int sctp_setsockopt_active_key(struct sock *sk,
3277 				      char __user *optval,
3278 				      unsigned int optlen)
3279 {
3280 	struct sctp_authkeyid val;
3281 	struct sctp_association *asoc;
3282 
3283 	if (!sctp_auth_enable)
3284 		return -EACCES;
3285 
3286 	if (optlen != sizeof(struct sctp_authkeyid))
3287 		return -EINVAL;
3288 	if (copy_from_user(&val, optval, optlen))
3289 		return -EFAULT;
3290 
3291 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3292 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3293 		return -EINVAL;
3294 
3295 	return sctp_auth_set_active_key(sctp_sk(sk)->ep, asoc,
3296 					val.scact_keynumber);
3297 }
3298 
3299 /*
3300  * 7.1.22.  Delete a shared key (SCTP_AUTH_DELETE_KEY)
3301  *
3302  * This set option will delete a shared secret key from use.
3303  */
3304 static int sctp_setsockopt_del_key(struct sock *sk,
3305 				   char __user *optval,
3306 				   unsigned int optlen)
3307 {
3308 	struct sctp_authkeyid val;
3309 	struct sctp_association *asoc;
3310 
3311 	if (!sctp_auth_enable)
3312 		return -EACCES;
3313 
3314 	if (optlen != sizeof(struct sctp_authkeyid))
3315 		return -EINVAL;
3316 	if (copy_from_user(&val, optval, optlen))
3317 		return -EFAULT;
3318 
3319 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3320 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3321 		return -EINVAL;
3322 
3323 	return sctp_auth_del_key_id(sctp_sk(sk)->ep, asoc,
3324 				    val.scact_keynumber);
3325 
3326 }
3327 
3328 
3329 /* API 6.2 setsockopt(), getsockopt()
3330  *
3331  * Applications use setsockopt() and getsockopt() to set or retrieve
3332  * socket options.  Socket options are used to change the default
3333  * behavior of sockets calls.  They are described in Section 7.
3334  *
3335  * The syntax is:
3336  *
3337  *   ret = getsockopt(int sd, int level, int optname, void __user *optval,
3338  *                    int __user *optlen);
3339  *   ret = setsockopt(int sd, int level, int optname, const void __user *optval,
3340  *                    int optlen);
3341  *
3342  *   sd      - the socket descript.
3343  *   level   - set to IPPROTO_SCTP for all SCTP options.
3344  *   optname - the option name.
3345  *   optval  - the buffer to store the value of the option.
3346  *   optlen  - the size of the buffer.
3347  */
3348 SCTP_STATIC int sctp_setsockopt(struct sock *sk, int level, int optname,
3349 				char __user *optval, unsigned int optlen)
3350 {
3351 	int retval = 0;
3352 
3353 	SCTP_DEBUG_PRINTK("sctp_setsockopt(sk: %p... optname: %d)\n",
3354 			  sk, optname);
3355 
3356 	/* I can hardly begin to describe how wrong this is.  This is
3357 	 * so broken as to be worse than useless.  The API draft
3358 	 * REALLY is NOT helpful here...  I am not convinced that the
3359 	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
3360 	 * are at all well-founded.
3361 	 */
3362 	if (level != SOL_SCTP) {
3363 		struct sctp_af *af = sctp_sk(sk)->pf->af;
3364 		retval = af->setsockopt(sk, level, optname, optval, optlen);
3365 		goto out_nounlock;
3366 	}
3367 
3368 	sctp_lock_sock(sk);
3369 
3370 	switch (optname) {
3371 	case SCTP_SOCKOPT_BINDX_ADD:
3372 		/* 'optlen' is the size of the addresses buffer. */
3373 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3374 					       optlen, SCTP_BINDX_ADD_ADDR);
3375 		break;
3376 
3377 	case SCTP_SOCKOPT_BINDX_REM:
3378 		/* 'optlen' is the size of the addresses buffer. */
3379 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3380 					       optlen, SCTP_BINDX_REM_ADDR);
3381 		break;
3382 
3383 	case SCTP_SOCKOPT_CONNECTX_OLD:
3384 		/* 'optlen' is the size of the addresses buffer. */
3385 		retval = sctp_setsockopt_connectx_old(sk,
3386 					    (struct sockaddr __user *)optval,
3387 					    optlen);
3388 		break;
3389 
3390 	case SCTP_SOCKOPT_CONNECTX:
3391 		/* 'optlen' is the size of the addresses buffer. */
3392 		retval = sctp_setsockopt_connectx(sk,
3393 					    (struct sockaddr __user *)optval,
3394 					    optlen);
3395 		break;
3396 
3397 	case SCTP_DISABLE_FRAGMENTS:
3398 		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
3399 		break;
3400 
3401 	case SCTP_EVENTS:
3402 		retval = sctp_setsockopt_events(sk, optval, optlen);
3403 		break;
3404 
3405 	case SCTP_AUTOCLOSE:
3406 		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
3407 		break;
3408 
3409 	case SCTP_PEER_ADDR_PARAMS:
3410 		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
3411 		break;
3412 
3413 	case SCTP_DELAYED_ACK:
3414 		retval = sctp_setsockopt_delayed_ack(sk, optval, optlen);
3415 		break;
3416 	case SCTP_PARTIAL_DELIVERY_POINT:
3417 		retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
3418 		break;
3419 
3420 	case SCTP_INITMSG:
3421 		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
3422 		break;
3423 	case SCTP_DEFAULT_SEND_PARAM:
3424 		retval = sctp_setsockopt_default_send_param(sk, optval,
3425 							    optlen);
3426 		break;
3427 	case SCTP_PRIMARY_ADDR:
3428 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
3429 		break;
3430 	case SCTP_SET_PEER_PRIMARY_ADDR:
3431 		retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
3432 		break;
3433 	case SCTP_NODELAY:
3434 		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
3435 		break;
3436 	case SCTP_RTOINFO:
3437 		retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
3438 		break;
3439 	case SCTP_ASSOCINFO:
3440 		retval = sctp_setsockopt_associnfo(sk, optval, optlen);
3441 		break;
3442 	case SCTP_I_WANT_MAPPED_V4_ADDR:
3443 		retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
3444 		break;
3445 	case SCTP_MAXSEG:
3446 		retval = sctp_setsockopt_maxseg(sk, optval, optlen);
3447 		break;
3448 	case SCTP_ADAPTATION_LAYER:
3449 		retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
3450 		break;
3451 	case SCTP_CONTEXT:
3452 		retval = sctp_setsockopt_context(sk, optval, optlen);
3453 		break;
3454 	case SCTP_FRAGMENT_INTERLEAVE:
3455 		retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
3456 		break;
3457 	case SCTP_MAX_BURST:
3458 		retval = sctp_setsockopt_maxburst(sk, optval, optlen);
3459 		break;
3460 	case SCTP_AUTH_CHUNK:
3461 		retval = sctp_setsockopt_auth_chunk(sk, optval, optlen);
3462 		break;
3463 	case SCTP_HMAC_IDENT:
3464 		retval = sctp_setsockopt_hmac_ident(sk, optval, optlen);
3465 		break;
3466 	case SCTP_AUTH_KEY:
3467 		retval = sctp_setsockopt_auth_key(sk, optval, optlen);
3468 		break;
3469 	case SCTP_AUTH_ACTIVE_KEY:
3470 		retval = sctp_setsockopt_active_key(sk, optval, optlen);
3471 		break;
3472 	case SCTP_AUTH_DELETE_KEY:
3473 		retval = sctp_setsockopt_del_key(sk, optval, optlen);
3474 		break;
3475 	default:
3476 		retval = -ENOPROTOOPT;
3477 		break;
3478 	}
3479 
3480 	sctp_release_sock(sk);
3481 
3482 out_nounlock:
3483 	return retval;
3484 }
3485 
3486 /* API 3.1.6 connect() - UDP Style Syntax
3487  *
3488  * An application may use the connect() call in the UDP model to initiate an
3489  * association without sending data.
3490  *
3491  * The syntax is:
3492  *
3493  * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
3494  *
3495  * sd: the socket descriptor to have a new association added to.
3496  *
3497  * nam: the address structure (either struct sockaddr_in or struct
3498  *    sockaddr_in6 defined in RFC2553 [7]).
3499  *
3500  * len: the size of the address.
3501  */
3502 SCTP_STATIC int sctp_connect(struct sock *sk, struct sockaddr *addr,
3503 			     int addr_len)
3504 {
3505 	int err = 0;
3506 	struct sctp_af *af;
3507 
3508 	sctp_lock_sock(sk);
3509 
3510 	SCTP_DEBUG_PRINTK("%s - sk: %p, sockaddr: %p, addr_len: %d\n",
3511 			  __func__, sk, addr, addr_len);
3512 
3513 	/* Validate addr_len before calling common connect/connectx routine. */
3514 	af = sctp_get_af_specific(addr->sa_family);
3515 	if (!af || addr_len < af->sockaddr_len) {
3516 		err = -EINVAL;
3517 	} else {
3518 		/* Pass correct addr len to common routine (so it knows there
3519 		 * is only one address being passed.
3520 		 */
3521 		err = __sctp_connect(sk, addr, af->sockaddr_len, NULL);
3522 	}
3523 
3524 	sctp_release_sock(sk);
3525 	return err;
3526 }
3527 
3528 /* FIXME: Write comments. */
3529 SCTP_STATIC int sctp_disconnect(struct sock *sk, int flags)
3530 {
3531 	return -EOPNOTSUPP; /* STUB */
3532 }
3533 
3534 /* 4.1.4 accept() - TCP Style Syntax
3535  *
3536  * Applications use accept() call to remove an established SCTP
3537  * association from the accept queue of the endpoint.  A new socket
3538  * descriptor will be returned from accept() to represent the newly
3539  * formed association.
3540  */
3541 SCTP_STATIC struct sock *sctp_accept(struct sock *sk, int flags, int *err)
3542 {
3543 	struct sctp_sock *sp;
3544 	struct sctp_endpoint *ep;
3545 	struct sock *newsk = NULL;
3546 	struct sctp_association *asoc;
3547 	long timeo;
3548 	int error = 0;
3549 
3550 	sctp_lock_sock(sk);
3551 
3552 	sp = sctp_sk(sk);
3553 	ep = sp->ep;
3554 
3555 	if (!sctp_style(sk, TCP)) {
3556 		error = -EOPNOTSUPP;
3557 		goto out;
3558 	}
3559 
3560 	if (!sctp_sstate(sk, LISTENING)) {
3561 		error = -EINVAL;
3562 		goto out;
3563 	}
3564 
3565 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
3566 
3567 	error = sctp_wait_for_accept(sk, timeo);
3568 	if (error)
3569 		goto out;
3570 
3571 	/* We treat the list of associations on the endpoint as the accept
3572 	 * queue and pick the first association on the list.
3573 	 */
3574 	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
3575 
3576 	newsk = sp->pf->create_accept_sk(sk, asoc);
3577 	if (!newsk) {
3578 		error = -ENOMEM;
3579 		goto out;
3580 	}
3581 
3582 	/* Populate the fields of the newsk from the oldsk and migrate the
3583 	 * asoc to the newsk.
3584 	 */
3585 	sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
3586 
3587 out:
3588 	sctp_release_sock(sk);
3589 	*err = error;
3590 	return newsk;
3591 }
3592 
3593 /* The SCTP ioctl handler. */
3594 SCTP_STATIC int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
3595 {
3596 	return -ENOIOCTLCMD;
3597 }
3598 
3599 /* This is the function which gets called during socket creation to
3600  * initialized the SCTP-specific portion of the sock.
3601  * The sock structure should already be zero-filled memory.
3602  */
3603 SCTP_STATIC int sctp_init_sock(struct sock *sk)
3604 {
3605 	struct sctp_endpoint *ep;
3606 	struct sctp_sock *sp;
3607 
3608 	SCTP_DEBUG_PRINTK("sctp_init_sock(sk: %p)\n", sk);
3609 
3610 	sp = sctp_sk(sk);
3611 
3612 	/* Initialize the SCTP per socket area.  */
3613 	switch (sk->sk_type) {
3614 	case SOCK_SEQPACKET:
3615 		sp->type = SCTP_SOCKET_UDP;
3616 		break;
3617 	case SOCK_STREAM:
3618 		sp->type = SCTP_SOCKET_TCP;
3619 		break;
3620 	default:
3621 		return -ESOCKTNOSUPPORT;
3622 	}
3623 
3624 	/* Initialize default send parameters. These parameters can be
3625 	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
3626 	 */
3627 	sp->default_stream = 0;
3628 	sp->default_ppid = 0;
3629 	sp->default_flags = 0;
3630 	sp->default_context = 0;
3631 	sp->default_timetolive = 0;
3632 
3633 	sp->default_rcv_context = 0;
3634 	sp->max_burst = sctp_max_burst;
3635 
3636 	/* Initialize default setup parameters. These parameters
3637 	 * can be modified with the SCTP_INITMSG socket option or
3638 	 * overridden by the SCTP_INIT CMSG.
3639 	 */
3640 	sp->initmsg.sinit_num_ostreams   = sctp_max_outstreams;
3641 	sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
3642 	sp->initmsg.sinit_max_attempts   = sctp_max_retrans_init;
3643 	sp->initmsg.sinit_max_init_timeo = sctp_rto_max;
3644 
3645 	/* Initialize default RTO related parameters.  These parameters can
3646 	 * be modified for with the SCTP_RTOINFO socket option.
3647 	 */
3648 	sp->rtoinfo.srto_initial = sctp_rto_initial;
3649 	sp->rtoinfo.srto_max     = sctp_rto_max;
3650 	sp->rtoinfo.srto_min     = sctp_rto_min;
3651 
3652 	/* Initialize default association related parameters. These parameters
3653 	 * can be modified with the SCTP_ASSOCINFO socket option.
3654 	 */
3655 	sp->assocparams.sasoc_asocmaxrxt = sctp_max_retrans_association;
3656 	sp->assocparams.sasoc_number_peer_destinations = 0;
3657 	sp->assocparams.sasoc_peer_rwnd = 0;
3658 	sp->assocparams.sasoc_local_rwnd = 0;
3659 	sp->assocparams.sasoc_cookie_life = sctp_valid_cookie_life;
3660 
3661 	/* Initialize default event subscriptions. By default, all the
3662 	 * options are off.
3663 	 */
3664 	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
3665 
3666 	/* Default Peer Address Parameters.  These defaults can
3667 	 * be modified via SCTP_PEER_ADDR_PARAMS
3668 	 */
3669 	sp->hbinterval  = sctp_hb_interval;
3670 	sp->pathmaxrxt  = sctp_max_retrans_path;
3671 	sp->pathmtu     = 0; // allow default discovery
3672 	sp->sackdelay   = sctp_sack_timeout;
3673 	sp->sackfreq	= 2;
3674 	sp->param_flags = SPP_HB_ENABLE |
3675 			  SPP_PMTUD_ENABLE |
3676 			  SPP_SACKDELAY_ENABLE;
3677 
3678 	/* If enabled no SCTP message fragmentation will be performed.
3679 	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
3680 	 */
3681 	sp->disable_fragments = 0;
3682 
3683 	/* Enable Nagle algorithm by default.  */
3684 	sp->nodelay           = 0;
3685 
3686 	/* Enable by default. */
3687 	sp->v4mapped          = 1;
3688 
3689 	/* Auto-close idle associations after the configured
3690 	 * number of seconds.  A value of 0 disables this
3691 	 * feature.  Configure through the SCTP_AUTOCLOSE socket option,
3692 	 * for UDP-style sockets only.
3693 	 */
3694 	sp->autoclose         = 0;
3695 
3696 	/* User specified fragmentation limit. */
3697 	sp->user_frag         = 0;
3698 
3699 	sp->adaptation_ind = 0;
3700 
3701 	sp->pf = sctp_get_pf_specific(sk->sk_family);
3702 
3703 	/* Control variables for partial data delivery. */
3704 	atomic_set(&sp->pd_mode, 0);
3705 	skb_queue_head_init(&sp->pd_lobby);
3706 	sp->frag_interleave = 0;
3707 
3708 	/* Create a per socket endpoint structure.  Even if we
3709 	 * change the data structure relationships, this may still
3710 	 * be useful for storing pre-connect address information.
3711 	 */
3712 	ep = sctp_endpoint_new(sk, GFP_KERNEL);
3713 	if (!ep)
3714 		return -ENOMEM;
3715 
3716 	sp->ep = ep;
3717 	sp->hmac = NULL;
3718 
3719 	SCTP_DBG_OBJCNT_INC(sock);
3720 	percpu_counter_inc(&sctp_sockets_allocated);
3721 
3722 	local_bh_disable();
3723 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
3724 	local_bh_enable();
3725 
3726 	return 0;
3727 }
3728 
3729 /* Cleanup any SCTP per socket resources.  */
3730 SCTP_STATIC void sctp_destroy_sock(struct sock *sk)
3731 {
3732 	struct sctp_endpoint *ep;
3733 
3734 	SCTP_DEBUG_PRINTK("sctp_destroy_sock(sk: %p)\n", sk);
3735 
3736 	/* Release our hold on the endpoint. */
3737 	ep = sctp_sk(sk)->ep;
3738 	sctp_endpoint_free(ep);
3739 	percpu_counter_dec(&sctp_sockets_allocated);
3740 	local_bh_disable();
3741 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
3742 	local_bh_enable();
3743 }
3744 
3745 /* API 4.1.7 shutdown() - TCP Style Syntax
3746  *     int shutdown(int socket, int how);
3747  *
3748  *     sd      - the socket descriptor of the association to be closed.
3749  *     how     - Specifies the type of shutdown.  The  values  are
3750  *               as follows:
3751  *               SHUT_RD
3752  *                     Disables further receive operations. No SCTP
3753  *                     protocol action is taken.
3754  *               SHUT_WR
3755  *                     Disables further send operations, and initiates
3756  *                     the SCTP shutdown sequence.
3757  *               SHUT_RDWR
3758  *                     Disables further send  and  receive  operations
3759  *                     and initiates the SCTP shutdown sequence.
3760  */
3761 SCTP_STATIC void sctp_shutdown(struct sock *sk, int how)
3762 {
3763 	struct sctp_endpoint *ep;
3764 	struct sctp_association *asoc;
3765 
3766 	if (!sctp_style(sk, TCP))
3767 		return;
3768 
3769 	if (how & SEND_SHUTDOWN) {
3770 		ep = sctp_sk(sk)->ep;
3771 		if (!list_empty(&ep->asocs)) {
3772 			asoc = list_entry(ep->asocs.next,
3773 					  struct sctp_association, asocs);
3774 			sctp_primitive_SHUTDOWN(asoc, NULL);
3775 		}
3776 	}
3777 }
3778 
3779 /* 7.2.1 Association Status (SCTP_STATUS)
3780 
3781  * Applications can retrieve current status information about an
3782  * association, including association state, peer receiver window size,
3783  * number of unacked data chunks, and number of data chunks pending
3784  * receipt.  This information is read-only.
3785  */
3786 static int sctp_getsockopt_sctp_status(struct sock *sk, int len,
3787 				       char __user *optval,
3788 				       int __user *optlen)
3789 {
3790 	struct sctp_status status;
3791 	struct sctp_association *asoc = NULL;
3792 	struct sctp_transport *transport;
3793 	sctp_assoc_t associd;
3794 	int retval = 0;
3795 
3796 	if (len < sizeof(status)) {
3797 		retval = -EINVAL;
3798 		goto out;
3799 	}
3800 
3801 	len = sizeof(status);
3802 	if (copy_from_user(&status, optval, len)) {
3803 		retval = -EFAULT;
3804 		goto out;
3805 	}
3806 
3807 	associd = status.sstat_assoc_id;
3808 	asoc = sctp_id2assoc(sk, associd);
3809 	if (!asoc) {
3810 		retval = -EINVAL;
3811 		goto out;
3812 	}
3813 
3814 	transport = asoc->peer.primary_path;
3815 
3816 	status.sstat_assoc_id = sctp_assoc2id(asoc);
3817 	status.sstat_state = asoc->state;
3818 	status.sstat_rwnd =  asoc->peer.rwnd;
3819 	status.sstat_unackdata = asoc->unack_data;
3820 
3821 	status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
3822 	status.sstat_instrms = asoc->c.sinit_max_instreams;
3823 	status.sstat_outstrms = asoc->c.sinit_num_ostreams;
3824 	status.sstat_fragmentation_point = asoc->frag_point;
3825 	status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3826 	memcpy(&status.sstat_primary.spinfo_address, &transport->ipaddr,
3827 			transport->af_specific->sockaddr_len);
3828 	/* Map ipv4 address into v4-mapped-on-v6 address.  */
3829 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
3830 		(union sctp_addr *)&status.sstat_primary.spinfo_address);
3831 	status.sstat_primary.spinfo_state = transport->state;
3832 	status.sstat_primary.spinfo_cwnd = transport->cwnd;
3833 	status.sstat_primary.spinfo_srtt = transport->srtt;
3834 	status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
3835 	status.sstat_primary.spinfo_mtu = transport->pathmtu;
3836 
3837 	if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
3838 		status.sstat_primary.spinfo_state = SCTP_ACTIVE;
3839 
3840 	if (put_user(len, optlen)) {
3841 		retval = -EFAULT;
3842 		goto out;
3843 	}
3844 
3845 	SCTP_DEBUG_PRINTK("sctp_getsockopt_sctp_status(%d): %d %d %d\n",
3846 			  len, status.sstat_state, status.sstat_rwnd,
3847 			  status.sstat_assoc_id);
3848 
3849 	if (copy_to_user(optval, &status, len)) {
3850 		retval = -EFAULT;
3851 		goto out;
3852 	}
3853 
3854 out:
3855 	return (retval);
3856 }
3857 
3858 
3859 /* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
3860  *
3861  * Applications can retrieve information about a specific peer address
3862  * of an association, including its reachability state, congestion
3863  * window, and retransmission timer values.  This information is
3864  * read-only.
3865  */
3866 static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
3867 					  char __user *optval,
3868 					  int __user *optlen)
3869 {
3870 	struct sctp_paddrinfo pinfo;
3871 	struct sctp_transport *transport;
3872 	int retval = 0;
3873 
3874 	if (len < sizeof(pinfo)) {
3875 		retval = -EINVAL;
3876 		goto out;
3877 	}
3878 
3879 	len = sizeof(pinfo);
3880 	if (copy_from_user(&pinfo, optval, len)) {
3881 		retval = -EFAULT;
3882 		goto out;
3883 	}
3884 
3885 	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
3886 					   pinfo.spinfo_assoc_id);
3887 	if (!transport)
3888 		return -EINVAL;
3889 
3890 	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3891 	pinfo.spinfo_state = transport->state;
3892 	pinfo.spinfo_cwnd = transport->cwnd;
3893 	pinfo.spinfo_srtt = transport->srtt;
3894 	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
3895 	pinfo.spinfo_mtu = transport->pathmtu;
3896 
3897 	if (pinfo.spinfo_state == SCTP_UNKNOWN)
3898 		pinfo.spinfo_state = SCTP_ACTIVE;
3899 
3900 	if (put_user(len, optlen)) {
3901 		retval = -EFAULT;
3902 		goto out;
3903 	}
3904 
3905 	if (copy_to_user(optval, &pinfo, len)) {
3906 		retval = -EFAULT;
3907 		goto out;
3908 	}
3909 
3910 out:
3911 	return (retval);
3912 }
3913 
3914 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
3915  *
3916  * This option is a on/off flag.  If enabled no SCTP message
3917  * fragmentation will be performed.  Instead if a message being sent
3918  * exceeds the current PMTU size, the message will NOT be sent and
3919  * instead a error will be indicated to the user.
3920  */
3921 static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
3922 					char __user *optval, int __user *optlen)
3923 {
3924 	int val;
3925 
3926 	if (len < sizeof(int))
3927 		return -EINVAL;
3928 
3929 	len = sizeof(int);
3930 	val = (sctp_sk(sk)->disable_fragments == 1);
3931 	if (put_user(len, optlen))
3932 		return -EFAULT;
3933 	if (copy_to_user(optval, &val, len))
3934 		return -EFAULT;
3935 	return 0;
3936 }
3937 
3938 /* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
3939  *
3940  * This socket option is used to specify various notifications and
3941  * ancillary data the user wishes to receive.
3942  */
3943 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
3944 				  int __user *optlen)
3945 {
3946 	if (len < sizeof(struct sctp_event_subscribe))
3947 		return -EINVAL;
3948 	len = sizeof(struct sctp_event_subscribe);
3949 	if (put_user(len, optlen))
3950 		return -EFAULT;
3951 	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
3952 		return -EFAULT;
3953 	return 0;
3954 }
3955 
3956 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
3957  *
3958  * This socket option is applicable to the UDP-style socket only.  When
3959  * set it will cause associations that are idle for more than the
3960  * specified number of seconds to automatically close.  An association
3961  * being idle is defined an association that has NOT sent or received
3962  * user data.  The special value of '0' indicates that no automatic
3963  * close of any associations should be performed.  The option expects an
3964  * integer defining the number of seconds of idle time before an
3965  * association is closed.
3966  */
3967 static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
3968 {
3969 	/* Applicable to UDP-style socket only */
3970 	if (sctp_style(sk, TCP))
3971 		return -EOPNOTSUPP;
3972 	if (len < sizeof(int))
3973 		return -EINVAL;
3974 	len = sizeof(int);
3975 	if (put_user(len, optlen))
3976 		return -EFAULT;
3977 	if (copy_to_user(optval, &sctp_sk(sk)->autoclose, sizeof(int)))
3978 		return -EFAULT;
3979 	return 0;
3980 }
3981 
3982 /* Helper routine to branch off an association to a new socket.  */
3983 SCTP_STATIC int sctp_do_peeloff(struct sctp_association *asoc,
3984 				struct socket **sockp)
3985 {
3986 	struct sock *sk = asoc->base.sk;
3987 	struct socket *sock;
3988 	struct sctp_af *af;
3989 	int err = 0;
3990 
3991 	/* An association cannot be branched off from an already peeled-off
3992 	 * socket, nor is this supported for tcp style sockets.
3993 	 */
3994 	if (!sctp_style(sk, UDP))
3995 		return -EINVAL;
3996 
3997 	/* Create a new socket.  */
3998 	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
3999 	if (err < 0)
4000 		return err;
4001 
4002 	sctp_copy_sock(sock->sk, sk, asoc);
4003 
4004 	/* Make peeled-off sockets more like 1-1 accepted sockets.
4005 	 * Set the daddr and initialize id to something more random
4006 	 */
4007 	af = sctp_get_af_specific(asoc->peer.primary_addr.sa.sa_family);
4008 	af->to_sk_daddr(&asoc->peer.primary_addr, sk);
4009 
4010 	/* Populate the fields of the newsk from the oldsk and migrate the
4011 	 * asoc to the newsk.
4012 	 */
4013 	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
4014 
4015 	*sockp = sock;
4016 
4017 	return err;
4018 }
4019 
4020 static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
4021 {
4022 	sctp_peeloff_arg_t peeloff;
4023 	struct socket *newsock;
4024 	int retval = 0;
4025 	struct sctp_association *asoc;
4026 
4027 	if (len < sizeof(sctp_peeloff_arg_t))
4028 		return -EINVAL;
4029 	len = sizeof(sctp_peeloff_arg_t);
4030 	if (copy_from_user(&peeloff, optval, len))
4031 		return -EFAULT;
4032 
4033 	asoc = sctp_id2assoc(sk, peeloff.associd);
4034 	if (!asoc) {
4035 		retval = -EINVAL;
4036 		goto out;
4037 	}
4038 
4039 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p\n", __func__, sk, asoc);
4040 
4041 	retval = sctp_do_peeloff(asoc, &newsock);
4042 	if (retval < 0)
4043 		goto out;
4044 
4045 	/* Map the socket to an unused fd that can be returned to the user.  */
4046 	retval = sock_map_fd(newsock, 0);
4047 	if (retval < 0) {
4048 		sock_release(newsock);
4049 		goto out;
4050 	}
4051 
4052 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p newsk: %p sd: %d\n",
4053 			  __func__, sk, asoc, newsock->sk, retval);
4054 
4055 	/* Return the fd mapped to the new socket.  */
4056 	peeloff.sd = retval;
4057 	if (put_user(len, optlen))
4058 		return -EFAULT;
4059 	if (copy_to_user(optval, &peeloff, len))
4060 		retval = -EFAULT;
4061 
4062 out:
4063 	return retval;
4064 }
4065 
4066 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
4067  *
4068  * Applications can enable or disable heartbeats for any peer address of
4069  * an association, modify an address's heartbeat interval, force a
4070  * heartbeat to be sent immediately, and adjust the address's maximum
4071  * number of retransmissions sent before an address is considered
4072  * unreachable.  The following structure is used to access and modify an
4073  * address's parameters:
4074  *
4075  *  struct sctp_paddrparams {
4076  *     sctp_assoc_t            spp_assoc_id;
4077  *     struct sockaddr_storage spp_address;
4078  *     uint32_t                spp_hbinterval;
4079  *     uint16_t                spp_pathmaxrxt;
4080  *     uint32_t                spp_pathmtu;
4081  *     uint32_t                spp_sackdelay;
4082  *     uint32_t                spp_flags;
4083  * };
4084  *
4085  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
4086  *                     application, and identifies the association for
4087  *                     this query.
4088  *   spp_address     - This specifies which address is of interest.
4089  *   spp_hbinterval  - This contains the value of the heartbeat interval,
4090  *                     in milliseconds.  If a  value of zero
4091  *                     is present in this field then no changes are to
4092  *                     be made to this parameter.
4093  *   spp_pathmaxrxt  - This contains the maximum number of
4094  *                     retransmissions before this address shall be
4095  *                     considered unreachable. If a  value of zero
4096  *                     is present in this field then no changes are to
4097  *                     be made to this parameter.
4098  *   spp_pathmtu     - When Path MTU discovery is disabled the value
4099  *                     specified here will be the "fixed" path mtu.
4100  *                     Note that if the spp_address field is empty
4101  *                     then all associations on this address will
4102  *                     have this fixed path mtu set upon them.
4103  *
4104  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
4105  *                     the number of milliseconds that sacks will be delayed
4106  *                     for. This value will apply to all addresses of an
4107  *                     association if the spp_address field is empty. Note
4108  *                     also, that if delayed sack is enabled and this
4109  *                     value is set to 0, no change is made to the last
4110  *                     recorded delayed sack timer value.
4111  *
4112  *   spp_flags       - These flags are used to control various features
4113  *                     on an association. The flag field may contain
4114  *                     zero or more of the following options.
4115  *
4116  *                     SPP_HB_ENABLE  - Enable heartbeats on the
4117  *                     specified address. Note that if the address
4118  *                     field is empty all addresses for the association
4119  *                     have heartbeats enabled upon them.
4120  *
4121  *                     SPP_HB_DISABLE - Disable heartbeats on the
4122  *                     speicifed address. Note that if the address
4123  *                     field is empty all addresses for the association
4124  *                     will have their heartbeats disabled. Note also
4125  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
4126  *                     mutually exclusive, only one of these two should
4127  *                     be specified. Enabling both fields will have
4128  *                     undetermined results.
4129  *
4130  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
4131  *                     to be made immediately.
4132  *
4133  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
4134  *                     discovery upon the specified address. Note that
4135  *                     if the address feild is empty then all addresses
4136  *                     on the association are effected.
4137  *
4138  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
4139  *                     discovery upon the specified address. Note that
4140  *                     if the address feild is empty then all addresses
4141  *                     on the association are effected. Not also that
4142  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
4143  *                     exclusive. Enabling both will have undetermined
4144  *                     results.
4145  *
4146  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
4147  *                     on delayed sack. The time specified in spp_sackdelay
4148  *                     is used to specify the sack delay for this address. Note
4149  *                     that if spp_address is empty then all addresses will
4150  *                     enable delayed sack and take on the sack delay
4151  *                     value specified in spp_sackdelay.
4152  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
4153  *                     off delayed sack. If the spp_address field is blank then
4154  *                     delayed sack is disabled for the entire association. Note
4155  *                     also that this field is mutually exclusive to
4156  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
4157  *                     results.
4158  */
4159 static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
4160 					    char __user *optval, int __user *optlen)
4161 {
4162 	struct sctp_paddrparams  params;
4163 	struct sctp_transport   *trans = NULL;
4164 	struct sctp_association *asoc = NULL;
4165 	struct sctp_sock        *sp = sctp_sk(sk);
4166 
4167 	if (len < sizeof(struct sctp_paddrparams))
4168 		return -EINVAL;
4169 	len = sizeof(struct sctp_paddrparams);
4170 	if (copy_from_user(&params, optval, len))
4171 		return -EFAULT;
4172 
4173 	/* If an address other than INADDR_ANY is specified, and
4174 	 * no transport is found, then the request is invalid.
4175 	 */
4176 	if (!sctp_is_any(sk, ( union sctp_addr *)&params.spp_address)) {
4177 		trans = sctp_addr_id2transport(sk, &params.spp_address,
4178 					       params.spp_assoc_id);
4179 		if (!trans) {
4180 			SCTP_DEBUG_PRINTK("Failed no transport\n");
4181 			return -EINVAL;
4182 		}
4183 	}
4184 
4185 	/* Get association, if assoc_id != 0 and the socket is a one
4186 	 * to many style socket, and an association was not found, then
4187 	 * the id was invalid.
4188 	 */
4189 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
4190 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
4191 		SCTP_DEBUG_PRINTK("Failed no association\n");
4192 		return -EINVAL;
4193 	}
4194 
4195 	if (trans) {
4196 		/* Fetch transport values. */
4197 		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
4198 		params.spp_pathmtu    = trans->pathmtu;
4199 		params.spp_pathmaxrxt = trans->pathmaxrxt;
4200 		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
4201 
4202 		/*draft-11 doesn't say what to return in spp_flags*/
4203 		params.spp_flags      = trans->param_flags;
4204 	} else if (asoc) {
4205 		/* Fetch association values. */
4206 		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
4207 		params.spp_pathmtu    = asoc->pathmtu;
4208 		params.spp_pathmaxrxt = asoc->pathmaxrxt;
4209 		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
4210 
4211 		/*draft-11 doesn't say what to return in spp_flags*/
4212 		params.spp_flags      = asoc->param_flags;
4213 	} else {
4214 		/* Fetch socket values. */
4215 		params.spp_hbinterval = sp->hbinterval;
4216 		params.spp_pathmtu    = sp->pathmtu;
4217 		params.spp_sackdelay  = sp->sackdelay;
4218 		params.spp_pathmaxrxt = sp->pathmaxrxt;
4219 
4220 		/*draft-11 doesn't say what to return in spp_flags*/
4221 		params.spp_flags      = sp->param_flags;
4222 	}
4223 
4224 	if (copy_to_user(optval, &params, len))
4225 		return -EFAULT;
4226 
4227 	if (put_user(len, optlen))
4228 		return -EFAULT;
4229 
4230 	return 0;
4231 }
4232 
4233 /*
4234  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
4235  *
4236  * This option will effect the way delayed acks are performed.  This
4237  * option allows you to get or set the delayed ack time, in
4238  * milliseconds.  It also allows changing the delayed ack frequency.
4239  * Changing the frequency to 1 disables the delayed sack algorithm.  If
4240  * the assoc_id is 0, then this sets or gets the endpoints default
4241  * values.  If the assoc_id field is non-zero, then the set or get
4242  * effects the specified association for the one to many model (the
4243  * assoc_id field is ignored by the one to one model).  Note that if
4244  * sack_delay or sack_freq are 0 when setting this option, then the
4245  * current values will remain unchanged.
4246  *
4247  * struct sctp_sack_info {
4248  *     sctp_assoc_t            sack_assoc_id;
4249  *     uint32_t                sack_delay;
4250  *     uint32_t                sack_freq;
4251  * };
4252  *
4253  * sack_assoc_id -  This parameter, indicates which association the user
4254  *    is performing an action upon.  Note that if this field's value is
4255  *    zero then the endpoints default value is changed (effecting future
4256  *    associations only).
4257  *
4258  * sack_delay -  This parameter contains the number of milliseconds that
4259  *    the user is requesting the delayed ACK timer be set to.  Note that
4260  *    this value is defined in the standard to be between 200 and 500
4261  *    milliseconds.
4262  *
4263  * sack_freq -  This parameter contains the number of packets that must
4264  *    be received before a sack is sent without waiting for the delay
4265  *    timer to expire.  The default value for this is 2, setting this
4266  *    value to 1 will disable the delayed sack algorithm.
4267  */
4268 static int sctp_getsockopt_delayed_ack(struct sock *sk, int len,
4269 					    char __user *optval,
4270 					    int __user *optlen)
4271 {
4272 	struct sctp_sack_info    params;
4273 	struct sctp_association *asoc = NULL;
4274 	struct sctp_sock        *sp = sctp_sk(sk);
4275 
4276 	if (len >= sizeof(struct sctp_sack_info)) {
4277 		len = sizeof(struct sctp_sack_info);
4278 
4279 		if (copy_from_user(&params, optval, len))
4280 			return -EFAULT;
4281 	} else if (len == sizeof(struct sctp_assoc_value)) {
4282 		printk(KERN_WARNING "SCTP: Use of struct sctp_assoc_value "
4283 		       "in delayed_ack socket option deprecated\n");
4284 		printk(KERN_WARNING "SCTP: Use struct sctp_sack_info instead\n");
4285 		if (copy_from_user(&params, optval, len))
4286 			return -EFAULT;
4287 	} else
4288 		return - EINVAL;
4289 
4290 	/* Get association, if sack_assoc_id != 0 and the socket is a one
4291 	 * to many style socket, and an association was not found, then
4292 	 * the id was invalid.
4293 	 */
4294 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
4295 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
4296 		return -EINVAL;
4297 
4298 	if (asoc) {
4299 		/* Fetch association values. */
4300 		if (asoc->param_flags & SPP_SACKDELAY_ENABLE) {
4301 			params.sack_delay = jiffies_to_msecs(
4302 				asoc->sackdelay);
4303 			params.sack_freq = asoc->sackfreq;
4304 
4305 		} else {
4306 			params.sack_delay = 0;
4307 			params.sack_freq = 1;
4308 		}
4309 	} else {
4310 		/* Fetch socket values. */
4311 		if (sp->param_flags & SPP_SACKDELAY_ENABLE) {
4312 			params.sack_delay  = sp->sackdelay;
4313 			params.sack_freq = sp->sackfreq;
4314 		} else {
4315 			params.sack_delay  = 0;
4316 			params.sack_freq = 1;
4317 		}
4318 	}
4319 
4320 	if (copy_to_user(optval, &params, len))
4321 		return -EFAULT;
4322 
4323 	if (put_user(len, optlen))
4324 		return -EFAULT;
4325 
4326 	return 0;
4327 }
4328 
4329 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
4330  *
4331  * Applications can specify protocol parameters for the default association
4332  * initialization.  The option name argument to setsockopt() and getsockopt()
4333  * is SCTP_INITMSG.
4334  *
4335  * Setting initialization parameters is effective only on an unconnected
4336  * socket (for UDP-style sockets only future associations are effected
4337  * by the change).  With TCP-style sockets, this option is inherited by
4338  * sockets derived from a listener socket.
4339  */
4340 static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
4341 {
4342 	if (len < sizeof(struct sctp_initmsg))
4343 		return -EINVAL;
4344 	len = sizeof(struct sctp_initmsg);
4345 	if (put_user(len, optlen))
4346 		return -EFAULT;
4347 	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
4348 		return -EFAULT;
4349 	return 0;
4350 }
4351 
4352 static int sctp_getsockopt_peer_addrs_num_old(struct sock *sk, int len,
4353 					      char __user *optval,
4354 					      int __user *optlen)
4355 {
4356 	sctp_assoc_t id;
4357 	struct sctp_association *asoc;
4358 	struct list_head *pos;
4359 	int cnt = 0;
4360 
4361 	if (len < sizeof(sctp_assoc_t))
4362 		return -EINVAL;
4363 
4364 	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
4365 		return -EFAULT;
4366 
4367 	printk(KERN_WARNING "SCTP: Use of SCTP_GET_PEER_ADDRS_NUM_OLD "
4368 			    "socket option deprecated\n");
4369 	/* For UDP-style sockets, id specifies the association to query.  */
4370 	asoc = sctp_id2assoc(sk, id);
4371 	if (!asoc)
4372 		return -EINVAL;
4373 
4374 	list_for_each(pos, &asoc->peer.transport_addr_list) {
4375 		cnt ++;
4376 	}
4377 
4378 	return cnt;
4379 }
4380 
4381 /*
4382  * Old API for getting list of peer addresses. Does not work for 32-bit
4383  * programs running on a 64-bit kernel
4384  */
4385 static int sctp_getsockopt_peer_addrs_old(struct sock *sk, int len,
4386 					  char __user *optval,
4387 					  int __user *optlen)
4388 {
4389 	struct sctp_association *asoc;
4390 	int cnt = 0;
4391 	struct sctp_getaddrs_old getaddrs;
4392 	struct sctp_transport *from;
4393 	void __user *to;
4394 	union sctp_addr temp;
4395 	struct sctp_sock *sp = sctp_sk(sk);
4396 	int addrlen;
4397 
4398 	if (len < sizeof(struct sctp_getaddrs_old))
4399 		return -EINVAL;
4400 
4401 	len = sizeof(struct sctp_getaddrs_old);
4402 
4403 	if (copy_from_user(&getaddrs, optval, len))
4404 		return -EFAULT;
4405 
4406 	if (getaddrs.addr_num <= 0) return -EINVAL;
4407 
4408 	printk(KERN_WARNING "SCTP: Use of SCTP_GET_PEER_ADDRS_OLD "
4409 			    "socket option deprecated\n");
4410 
4411 	/* For UDP-style sockets, id specifies the association to query.  */
4412 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4413 	if (!asoc)
4414 		return -EINVAL;
4415 
4416 	to = (void __user *)getaddrs.addrs;
4417 	list_for_each_entry(from, &asoc->peer.transport_addr_list,
4418 				transports) {
4419 		memcpy(&temp, &from->ipaddr, sizeof(temp));
4420 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4421 		addrlen = sctp_get_af_specific(sk->sk_family)->sockaddr_len;
4422 		if (copy_to_user(to, &temp, addrlen))
4423 			return -EFAULT;
4424 		to += addrlen ;
4425 		cnt ++;
4426 		if (cnt >= getaddrs.addr_num) break;
4427 	}
4428 	getaddrs.addr_num = cnt;
4429 	if (put_user(len, optlen))
4430 		return -EFAULT;
4431 	if (copy_to_user(optval, &getaddrs, len))
4432 		return -EFAULT;
4433 
4434 	return 0;
4435 }
4436 
4437 static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
4438 				      char __user *optval, int __user *optlen)
4439 {
4440 	struct sctp_association *asoc;
4441 	int cnt = 0;
4442 	struct sctp_getaddrs getaddrs;
4443 	struct sctp_transport *from;
4444 	void __user *to;
4445 	union sctp_addr temp;
4446 	struct sctp_sock *sp = sctp_sk(sk);
4447 	int addrlen;
4448 	size_t space_left;
4449 	int bytes_copied;
4450 
4451 	if (len < sizeof(struct sctp_getaddrs))
4452 		return -EINVAL;
4453 
4454 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4455 		return -EFAULT;
4456 
4457 	/* For UDP-style sockets, id specifies the association to query.  */
4458 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4459 	if (!asoc)
4460 		return -EINVAL;
4461 
4462 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4463 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4464 
4465 	list_for_each_entry(from, &asoc->peer.transport_addr_list,
4466 				transports) {
4467 		memcpy(&temp, &from->ipaddr, sizeof(temp));
4468 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4469 		addrlen = sctp_get_af_specific(sk->sk_family)->sockaddr_len;
4470 		if (space_left < addrlen)
4471 			return -ENOMEM;
4472 		if (copy_to_user(to, &temp, addrlen))
4473 			return -EFAULT;
4474 		to += addrlen;
4475 		cnt++;
4476 		space_left -= addrlen;
4477 	}
4478 
4479 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
4480 		return -EFAULT;
4481 	bytes_copied = ((char __user *)to) - optval;
4482 	if (put_user(bytes_copied, optlen))
4483 		return -EFAULT;
4484 
4485 	return 0;
4486 }
4487 
4488 static int sctp_getsockopt_local_addrs_num_old(struct sock *sk, int len,
4489 					       char __user *optval,
4490 					       int __user *optlen)
4491 {
4492 	sctp_assoc_t id;
4493 	struct sctp_bind_addr *bp;
4494 	struct sctp_association *asoc;
4495 	struct sctp_sockaddr_entry *addr;
4496 	int cnt = 0;
4497 
4498 	if (len < sizeof(sctp_assoc_t))
4499 		return -EINVAL;
4500 
4501 	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
4502 		return -EFAULT;
4503 
4504 	printk(KERN_WARNING "SCTP: Use of SCTP_GET_LOCAL_ADDRS_NUM_OLD "
4505 			    "socket option deprecated\n");
4506 
4507 	/*
4508 	 *  For UDP-style sockets, id specifies the association to query.
4509 	 *  If the id field is set to the value '0' then the locally bound
4510 	 *  addresses are returned without regard to any particular
4511 	 *  association.
4512 	 */
4513 	if (0 == id) {
4514 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4515 	} else {
4516 		asoc = sctp_id2assoc(sk, id);
4517 		if (!asoc)
4518 			return -EINVAL;
4519 		bp = &asoc->base.bind_addr;
4520 	}
4521 
4522 	/* If the endpoint is bound to 0.0.0.0 or ::0, count the valid
4523 	 * addresses from the global local address list.
4524 	 */
4525 	if (sctp_list_single_entry(&bp->address_list)) {
4526 		addr = list_entry(bp->address_list.next,
4527 				  struct sctp_sockaddr_entry, list);
4528 		if (sctp_is_any(sk, &addr->a)) {
4529 			rcu_read_lock();
4530 			list_for_each_entry_rcu(addr,
4531 						&sctp_local_addr_list, list) {
4532 				if (!addr->valid)
4533 					continue;
4534 
4535 				if ((PF_INET == sk->sk_family) &&
4536 				    (AF_INET6 == addr->a.sa.sa_family))
4537 					continue;
4538 
4539 				if ((PF_INET6 == sk->sk_family) &&
4540 				    inet_v6_ipv6only(sk) &&
4541 				    (AF_INET == addr->a.sa.sa_family))
4542 					continue;
4543 
4544 				cnt++;
4545 			}
4546 			rcu_read_unlock();
4547 		} else {
4548 			cnt = 1;
4549 		}
4550 		goto done;
4551 	}
4552 
4553 	/* Protection on the bound address list is not needed,
4554 	 * since in the socket option context we hold the socket lock,
4555 	 * so there is no way that the bound address list can change.
4556 	 */
4557 	list_for_each_entry(addr, &bp->address_list, list) {
4558 		cnt ++;
4559 	}
4560 done:
4561 	return cnt;
4562 }
4563 
4564 /* Helper function that copies local addresses to user and returns the number
4565  * of addresses copied.
4566  */
4567 static int sctp_copy_laddrs_old(struct sock *sk, __u16 port,
4568 					int max_addrs, void *to,
4569 					int *bytes_copied)
4570 {
4571 	struct sctp_sockaddr_entry *addr;
4572 	union sctp_addr temp;
4573 	int cnt = 0;
4574 	int addrlen;
4575 
4576 	rcu_read_lock();
4577 	list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
4578 		if (!addr->valid)
4579 			continue;
4580 
4581 		if ((PF_INET == sk->sk_family) &&
4582 		    (AF_INET6 == addr->a.sa.sa_family))
4583 			continue;
4584 		if ((PF_INET6 == sk->sk_family) &&
4585 		    inet_v6_ipv6only(sk) &&
4586 		    (AF_INET == addr->a.sa.sa_family))
4587 			continue;
4588 		memcpy(&temp, &addr->a, sizeof(temp));
4589 		if (!temp.v4.sin_port)
4590 			temp.v4.sin_port = htons(port);
4591 
4592 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4593 								&temp);
4594 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4595 		memcpy(to, &temp, addrlen);
4596 
4597 		to += addrlen;
4598 		*bytes_copied += addrlen;
4599 		cnt ++;
4600 		if (cnt >= max_addrs) break;
4601 	}
4602 	rcu_read_unlock();
4603 
4604 	return cnt;
4605 }
4606 
4607 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
4608 			    size_t space_left, int *bytes_copied)
4609 {
4610 	struct sctp_sockaddr_entry *addr;
4611 	union sctp_addr temp;
4612 	int cnt = 0;
4613 	int addrlen;
4614 
4615 	rcu_read_lock();
4616 	list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
4617 		if (!addr->valid)
4618 			continue;
4619 
4620 		if ((PF_INET == sk->sk_family) &&
4621 		    (AF_INET6 == addr->a.sa.sa_family))
4622 			continue;
4623 		if ((PF_INET6 == sk->sk_family) &&
4624 		    inet_v6_ipv6only(sk) &&
4625 		    (AF_INET == addr->a.sa.sa_family))
4626 			continue;
4627 		memcpy(&temp, &addr->a, sizeof(temp));
4628 		if (!temp.v4.sin_port)
4629 			temp.v4.sin_port = htons(port);
4630 
4631 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4632 								&temp);
4633 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4634 		if (space_left < addrlen) {
4635 			cnt =  -ENOMEM;
4636 			break;
4637 		}
4638 		memcpy(to, &temp, addrlen);
4639 
4640 		to += addrlen;
4641 		cnt ++;
4642 		space_left -= addrlen;
4643 		*bytes_copied += addrlen;
4644 	}
4645 	rcu_read_unlock();
4646 
4647 	return cnt;
4648 }
4649 
4650 /* Old API for getting list of local addresses. Does not work for 32-bit
4651  * programs running on a 64-bit kernel
4652  */
4653 static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
4654 					   char __user *optval, int __user *optlen)
4655 {
4656 	struct sctp_bind_addr *bp;
4657 	struct sctp_association *asoc;
4658 	int cnt = 0;
4659 	struct sctp_getaddrs_old getaddrs;
4660 	struct sctp_sockaddr_entry *addr;
4661 	void __user *to;
4662 	union sctp_addr temp;
4663 	struct sctp_sock *sp = sctp_sk(sk);
4664 	int addrlen;
4665 	int err = 0;
4666 	void *addrs;
4667 	void *buf;
4668 	int bytes_copied = 0;
4669 
4670 	if (len < sizeof(struct sctp_getaddrs_old))
4671 		return -EINVAL;
4672 
4673 	len = sizeof(struct sctp_getaddrs_old);
4674 	if (copy_from_user(&getaddrs, optval, len))
4675 		return -EFAULT;
4676 
4677 	if (getaddrs.addr_num <= 0 ||
4678 	    getaddrs.addr_num >= (INT_MAX / sizeof(union sctp_addr)))
4679 		return -EINVAL;
4680 
4681 	printk(KERN_WARNING "SCTP: Use of SCTP_GET_LOCAL_ADDRS_OLD "
4682 			    "socket option deprecated\n");
4683 
4684 	/*
4685 	 *  For UDP-style sockets, id specifies the association to query.
4686 	 *  If the id field is set to the value '0' then the locally bound
4687 	 *  addresses are returned without regard to any particular
4688 	 *  association.
4689 	 */
4690 	if (0 == getaddrs.assoc_id) {
4691 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4692 	} else {
4693 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4694 		if (!asoc)
4695 			return -EINVAL;
4696 		bp = &asoc->base.bind_addr;
4697 	}
4698 
4699 	to = getaddrs.addrs;
4700 
4701 	/* Allocate space for a local instance of packed array to hold all
4702 	 * the data.  We store addresses here first and then put write them
4703 	 * to the user in one shot.
4704 	 */
4705 	addrs = kmalloc(sizeof(union sctp_addr) * getaddrs.addr_num,
4706 			GFP_KERNEL);
4707 	if (!addrs)
4708 		return -ENOMEM;
4709 
4710 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4711 	 * addresses from the global local address list.
4712 	 */
4713 	if (sctp_list_single_entry(&bp->address_list)) {
4714 		addr = list_entry(bp->address_list.next,
4715 				  struct sctp_sockaddr_entry, list);
4716 		if (sctp_is_any(sk, &addr->a)) {
4717 			cnt = sctp_copy_laddrs_old(sk, bp->port,
4718 						   getaddrs.addr_num,
4719 						   addrs, &bytes_copied);
4720 			goto copy_getaddrs;
4721 		}
4722 	}
4723 
4724 	buf = addrs;
4725 	/* Protection on the bound address list is not needed since
4726 	 * in the socket option context we hold a socket lock and
4727 	 * thus the bound address list can't change.
4728 	 */
4729 	list_for_each_entry(addr, &bp->address_list, list) {
4730 		memcpy(&temp, &addr->a, sizeof(temp));
4731 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4732 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4733 		memcpy(buf, &temp, addrlen);
4734 		buf += addrlen;
4735 		bytes_copied += addrlen;
4736 		cnt ++;
4737 		if (cnt >= getaddrs.addr_num) break;
4738 	}
4739 
4740 copy_getaddrs:
4741 	/* copy the entire address list into the user provided space */
4742 	if (copy_to_user(to, addrs, bytes_copied)) {
4743 		err = -EFAULT;
4744 		goto error;
4745 	}
4746 
4747 	/* copy the leading structure back to user */
4748 	getaddrs.addr_num = cnt;
4749 	if (copy_to_user(optval, &getaddrs, len))
4750 		err = -EFAULT;
4751 
4752 error:
4753 	kfree(addrs);
4754 	return err;
4755 }
4756 
4757 static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
4758 				       char __user *optval, int __user *optlen)
4759 {
4760 	struct sctp_bind_addr *bp;
4761 	struct sctp_association *asoc;
4762 	int cnt = 0;
4763 	struct sctp_getaddrs getaddrs;
4764 	struct sctp_sockaddr_entry *addr;
4765 	void __user *to;
4766 	union sctp_addr temp;
4767 	struct sctp_sock *sp = sctp_sk(sk);
4768 	int addrlen;
4769 	int err = 0;
4770 	size_t space_left;
4771 	int bytes_copied = 0;
4772 	void *addrs;
4773 	void *buf;
4774 
4775 	if (len < sizeof(struct sctp_getaddrs))
4776 		return -EINVAL;
4777 
4778 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4779 		return -EFAULT;
4780 
4781 	/*
4782 	 *  For UDP-style sockets, id specifies the association to query.
4783 	 *  If the id field is set to the value '0' then the locally bound
4784 	 *  addresses are returned without regard to any particular
4785 	 *  association.
4786 	 */
4787 	if (0 == getaddrs.assoc_id) {
4788 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4789 	} else {
4790 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4791 		if (!asoc)
4792 			return -EINVAL;
4793 		bp = &asoc->base.bind_addr;
4794 	}
4795 
4796 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4797 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4798 
4799 	addrs = kmalloc(space_left, GFP_KERNEL);
4800 	if (!addrs)
4801 		return -ENOMEM;
4802 
4803 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4804 	 * addresses from the global local address list.
4805 	 */
4806 	if (sctp_list_single_entry(&bp->address_list)) {
4807 		addr = list_entry(bp->address_list.next,
4808 				  struct sctp_sockaddr_entry, list);
4809 		if (sctp_is_any(sk, &addr->a)) {
4810 			cnt = sctp_copy_laddrs(sk, bp->port, addrs,
4811 						space_left, &bytes_copied);
4812 			if (cnt < 0) {
4813 				err = cnt;
4814 				goto out;
4815 			}
4816 			goto copy_getaddrs;
4817 		}
4818 	}
4819 
4820 	buf = addrs;
4821 	/* Protection on the bound address list is not needed since
4822 	 * in the socket option context we hold a socket lock and
4823 	 * thus the bound address list can't change.
4824 	 */
4825 	list_for_each_entry(addr, &bp->address_list, list) {
4826 		memcpy(&temp, &addr->a, sizeof(temp));
4827 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4828 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4829 		if (space_left < addrlen) {
4830 			err =  -ENOMEM; /*fixme: right error?*/
4831 			goto out;
4832 		}
4833 		memcpy(buf, &temp, addrlen);
4834 		buf += addrlen;
4835 		bytes_copied += addrlen;
4836 		cnt ++;
4837 		space_left -= addrlen;
4838 	}
4839 
4840 copy_getaddrs:
4841 	if (copy_to_user(to, addrs, bytes_copied)) {
4842 		err = -EFAULT;
4843 		goto out;
4844 	}
4845 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num)) {
4846 		err = -EFAULT;
4847 		goto out;
4848 	}
4849 	if (put_user(bytes_copied, optlen))
4850 		err = -EFAULT;
4851 out:
4852 	kfree(addrs);
4853 	return err;
4854 }
4855 
4856 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
4857  *
4858  * Requests that the local SCTP stack use the enclosed peer address as
4859  * the association primary.  The enclosed address must be one of the
4860  * association peer's addresses.
4861  */
4862 static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
4863 					char __user *optval, int __user *optlen)
4864 {
4865 	struct sctp_prim prim;
4866 	struct sctp_association *asoc;
4867 	struct sctp_sock *sp = sctp_sk(sk);
4868 
4869 	if (len < sizeof(struct sctp_prim))
4870 		return -EINVAL;
4871 
4872 	len = sizeof(struct sctp_prim);
4873 
4874 	if (copy_from_user(&prim, optval, len))
4875 		return -EFAULT;
4876 
4877 	asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
4878 	if (!asoc)
4879 		return -EINVAL;
4880 
4881 	if (!asoc->peer.primary_path)
4882 		return -ENOTCONN;
4883 
4884 	memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
4885 		asoc->peer.primary_path->af_specific->sockaddr_len);
4886 
4887 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp,
4888 			(union sctp_addr *)&prim.ssp_addr);
4889 
4890 	if (put_user(len, optlen))
4891 		return -EFAULT;
4892 	if (copy_to_user(optval, &prim, len))
4893 		return -EFAULT;
4894 
4895 	return 0;
4896 }
4897 
4898 /*
4899  * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
4900  *
4901  * Requests that the local endpoint set the specified Adaptation Layer
4902  * Indication parameter for all future INIT and INIT-ACK exchanges.
4903  */
4904 static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
4905 				  char __user *optval, int __user *optlen)
4906 {
4907 	struct sctp_setadaptation adaptation;
4908 
4909 	if (len < sizeof(struct sctp_setadaptation))
4910 		return -EINVAL;
4911 
4912 	len = sizeof(struct sctp_setadaptation);
4913 
4914 	adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
4915 
4916 	if (put_user(len, optlen))
4917 		return -EFAULT;
4918 	if (copy_to_user(optval, &adaptation, len))
4919 		return -EFAULT;
4920 
4921 	return 0;
4922 }
4923 
4924 /*
4925  *
4926  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
4927  *
4928  *   Applications that wish to use the sendto() system call may wish to
4929  *   specify a default set of parameters that would normally be supplied
4930  *   through the inclusion of ancillary data.  This socket option allows
4931  *   such an application to set the default sctp_sndrcvinfo structure.
4932 
4933 
4934  *   The application that wishes to use this socket option simply passes
4935  *   in to this call the sctp_sndrcvinfo structure defined in Section
4936  *   5.2.2) The input parameters accepted by this call include
4937  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
4938  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
4939  *   to this call if the caller is using the UDP model.
4940  *
4941  *   For getsockopt, it get the default sctp_sndrcvinfo structure.
4942  */
4943 static int sctp_getsockopt_default_send_param(struct sock *sk,
4944 					int len, char __user *optval,
4945 					int __user *optlen)
4946 {
4947 	struct sctp_sndrcvinfo info;
4948 	struct sctp_association *asoc;
4949 	struct sctp_sock *sp = sctp_sk(sk);
4950 
4951 	if (len < sizeof(struct sctp_sndrcvinfo))
4952 		return -EINVAL;
4953 
4954 	len = sizeof(struct sctp_sndrcvinfo);
4955 
4956 	if (copy_from_user(&info, optval, len))
4957 		return -EFAULT;
4958 
4959 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
4960 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
4961 		return -EINVAL;
4962 
4963 	if (asoc) {
4964 		info.sinfo_stream = asoc->default_stream;
4965 		info.sinfo_flags = asoc->default_flags;
4966 		info.sinfo_ppid = asoc->default_ppid;
4967 		info.sinfo_context = asoc->default_context;
4968 		info.sinfo_timetolive = asoc->default_timetolive;
4969 	} else {
4970 		info.sinfo_stream = sp->default_stream;
4971 		info.sinfo_flags = sp->default_flags;
4972 		info.sinfo_ppid = sp->default_ppid;
4973 		info.sinfo_context = sp->default_context;
4974 		info.sinfo_timetolive = sp->default_timetolive;
4975 	}
4976 
4977 	if (put_user(len, optlen))
4978 		return -EFAULT;
4979 	if (copy_to_user(optval, &info, len))
4980 		return -EFAULT;
4981 
4982 	return 0;
4983 }
4984 
4985 /*
4986  *
4987  * 7.1.5 SCTP_NODELAY
4988  *
4989  * Turn on/off any Nagle-like algorithm.  This means that packets are
4990  * generally sent as soon as possible and no unnecessary delays are
4991  * introduced, at the cost of more packets in the network.  Expects an
4992  * integer boolean flag.
4993  */
4994 
4995 static int sctp_getsockopt_nodelay(struct sock *sk, int len,
4996 				   char __user *optval, int __user *optlen)
4997 {
4998 	int val;
4999 
5000 	if (len < sizeof(int))
5001 		return -EINVAL;
5002 
5003 	len = sizeof(int);
5004 	val = (sctp_sk(sk)->nodelay == 1);
5005 	if (put_user(len, optlen))
5006 		return -EFAULT;
5007 	if (copy_to_user(optval, &val, len))
5008 		return -EFAULT;
5009 	return 0;
5010 }
5011 
5012 /*
5013  *
5014  * 7.1.1 SCTP_RTOINFO
5015  *
5016  * The protocol parameters used to initialize and bound retransmission
5017  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
5018  * and modify these parameters.
5019  * All parameters are time values, in milliseconds.  A value of 0, when
5020  * modifying the parameters, indicates that the current value should not
5021  * be changed.
5022  *
5023  */
5024 static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
5025 				char __user *optval,
5026 				int __user *optlen) {
5027 	struct sctp_rtoinfo rtoinfo;
5028 	struct sctp_association *asoc;
5029 
5030 	if (len < sizeof (struct sctp_rtoinfo))
5031 		return -EINVAL;
5032 
5033 	len = sizeof(struct sctp_rtoinfo);
5034 
5035 	if (copy_from_user(&rtoinfo, optval, len))
5036 		return -EFAULT;
5037 
5038 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
5039 
5040 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
5041 		return -EINVAL;
5042 
5043 	/* Values corresponding to the specific association. */
5044 	if (asoc) {
5045 		rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
5046 		rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
5047 		rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
5048 	} else {
5049 		/* Values corresponding to the endpoint. */
5050 		struct sctp_sock *sp = sctp_sk(sk);
5051 
5052 		rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
5053 		rtoinfo.srto_max = sp->rtoinfo.srto_max;
5054 		rtoinfo.srto_min = sp->rtoinfo.srto_min;
5055 	}
5056 
5057 	if (put_user(len, optlen))
5058 		return -EFAULT;
5059 
5060 	if (copy_to_user(optval, &rtoinfo, len))
5061 		return -EFAULT;
5062 
5063 	return 0;
5064 }
5065 
5066 /*
5067  *
5068  * 7.1.2 SCTP_ASSOCINFO
5069  *
5070  * This option is used to tune the maximum retransmission attempts
5071  * of the association.
5072  * Returns an error if the new association retransmission value is
5073  * greater than the sum of the retransmission value  of the peer.
5074  * See [SCTP] for more information.
5075  *
5076  */
5077 static int sctp_getsockopt_associnfo(struct sock *sk, int len,
5078 				     char __user *optval,
5079 				     int __user *optlen)
5080 {
5081 
5082 	struct sctp_assocparams assocparams;
5083 	struct sctp_association *asoc;
5084 	struct list_head *pos;
5085 	int cnt = 0;
5086 
5087 	if (len < sizeof (struct sctp_assocparams))
5088 		return -EINVAL;
5089 
5090 	len = sizeof(struct sctp_assocparams);
5091 
5092 	if (copy_from_user(&assocparams, optval, len))
5093 		return -EFAULT;
5094 
5095 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
5096 
5097 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
5098 		return -EINVAL;
5099 
5100 	/* Values correspoinding to the specific association */
5101 	if (asoc) {
5102 		assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
5103 		assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
5104 		assocparams.sasoc_local_rwnd = asoc->a_rwnd;
5105 		assocparams.sasoc_cookie_life = (asoc->cookie_life.tv_sec
5106 						* 1000) +
5107 						(asoc->cookie_life.tv_usec
5108 						/ 1000);
5109 
5110 		list_for_each(pos, &asoc->peer.transport_addr_list) {
5111 			cnt ++;
5112 		}
5113 
5114 		assocparams.sasoc_number_peer_destinations = cnt;
5115 	} else {
5116 		/* Values corresponding to the endpoint */
5117 		struct sctp_sock *sp = sctp_sk(sk);
5118 
5119 		assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
5120 		assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
5121 		assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
5122 		assocparams.sasoc_cookie_life =
5123 					sp->assocparams.sasoc_cookie_life;
5124 		assocparams.sasoc_number_peer_destinations =
5125 					sp->assocparams.
5126 					sasoc_number_peer_destinations;
5127 	}
5128 
5129 	if (put_user(len, optlen))
5130 		return -EFAULT;
5131 
5132 	if (copy_to_user(optval, &assocparams, len))
5133 		return -EFAULT;
5134 
5135 	return 0;
5136 }
5137 
5138 /*
5139  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
5140  *
5141  * This socket option is a boolean flag which turns on or off mapped V4
5142  * addresses.  If this option is turned on and the socket is type
5143  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
5144  * If this option is turned off, then no mapping will be done of V4
5145  * addresses and a user will receive both PF_INET6 and PF_INET type
5146  * addresses on the socket.
5147  */
5148 static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
5149 				    char __user *optval, int __user *optlen)
5150 {
5151 	int val;
5152 	struct sctp_sock *sp = sctp_sk(sk);
5153 
5154 	if (len < sizeof(int))
5155 		return -EINVAL;
5156 
5157 	len = sizeof(int);
5158 	val = sp->v4mapped;
5159 	if (put_user(len, optlen))
5160 		return -EFAULT;
5161 	if (copy_to_user(optval, &val, len))
5162 		return -EFAULT;
5163 
5164 	return 0;
5165 }
5166 
5167 /*
5168  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
5169  * (chapter and verse is quoted at sctp_setsockopt_context())
5170  */
5171 static int sctp_getsockopt_context(struct sock *sk, int len,
5172 				   char __user *optval, int __user *optlen)
5173 {
5174 	struct sctp_assoc_value params;
5175 	struct sctp_sock *sp;
5176 	struct sctp_association *asoc;
5177 
5178 	if (len < sizeof(struct sctp_assoc_value))
5179 		return -EINVAL;
5180 
5181 	len = sizeof(struct sctp_assoc_value);
5182 
5183 	if (copy_from_user(&params, optval, len))
5184 		return -EFAULT;
5185 
5186 	sp = sctp_sk(sk);
5187 
5188 	if (params.assoc_id != 0) {
5189 		asoc = sctp_id2assoc(sk, params.assoc_id);
5190 		if (!asoc)
5191 			return -EINVAL;
5192 		params.assoc_value = asoc->default_rcv_context;
5193 	} else {
5194 		params.assoc_value = sp->default_rcv_context;
5195 	}
5196 
5197 	if (put_user(len, optlen))
5198 		return -EFAULT;
5199 	if (copy_to_user(optval, &params, len))
5200 		return -EFAULT;
5201 
5202 	return 0;
5203 }
5204 
5205 /*
5206  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
5207  * This option will get or set the maximum size to put in any outgoing
5208  * SCTP DATA chunk.  If a message is larger than this size it will be
5209  * fragmented by SCTP into the specified size.  Note that the underlying
5210  * SCTP implementation may fragment into smaller sized chunks when the
5211  * PMTU of the underlying association is smaller than the value set by
5212  * the user.  The default value for this option is '0' which indicates
5213  * the user is NOT limiting fragmentation and only the PMTU will effect
5214  * SCTP's choice of DATA chunk size.  Note also that values set larger
5215  * than the maximum size of an IP datagram will effectively let SCTP
5216  * control fragmentation (i.e. the same as setting this option to 0).
5217  *
5218  * The following structure is used to access and modify this parameter:
5219  *
5220  * struct sctp_assoc_value {
5221  *   sctp_assoc_t assoc_id;
5222  *   uint32_t assoc_value;
5223  * };
5224  *
5225  * assoc_id:  This parameter is ignored for one-to-one style sockets.
5226  *    For one-to-many style sockets this parameter indicates which
5227  *    association the user is performing an action upon.  Note that if
5228  *    this field's value is zero then the endpoints default value is
5229  *    changed (effecting future associations only).
5230  * assoc_value:  This parameter specifies the maximum size in bytes.
5231  */
5232 static int sctp_getsockopt_maxseg(struct sock *sk, int len,
5233 				  char __user *optval, int __user *optlen)
5234 {
5235 	struct sctp_assoc_value params;
5236 	struct sctp_association *asoc;
5237 
5238 	if (len == sizeof(int)) {
5239 		printk(KERN_WARNING
5240 		   "SCTP: Use of int in maxseg socket option deprecated\n");
5241 		printk(KERN_WARNING
5242 		   "SCTP: Use struct sctp_assoc_value instead\n");
5243 		params.assoc_id = 0;
5244 	} else if (len >= sizeof(struct sctp_assoc_value)) {
5245 		len = sizeof(struct sctp_assoc_value);
5246 		if (copy_from_user(&params, optval, sizeof(params)))
5247 			return -EFAULT;
5248 	} else
5249 		return -EINVAL;
5250 
5251 	asoc = sctp_id2assoc(sk, params.assoc_id);
5252 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
5253 		return -EINVAL;
5254 
5255 	if (asoc)
5256 		params.assoc_value = asoc->frag_point;
5257 	else
5258 		params.assoc_value = sctp_sk(sk)->user_frag;
5259 
5260 	if (put_user(len, optlen))
5261 		return -EFAULT;
5262 	if (len == sizeof(int)) {
5263 		if (copy_to_user(optval, &params.assoc_value, len))
5264 			return -EFAULT;
5265 	} else {
5266 		if (copy_to_user(optval, &params, len))
5267 			return -EFAULT;
5268 	}
5269 
5270 	return 0;
5271 }
5272 
5273 /*
5274  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
5275  * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
5276  */
5277 static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
5278 					       char __user *optval, int __user *optlen)
5279 {
5280 	int val;
5281 
5282 	if (len < sizeof(int))
5283 		return -EINVAL;
5284 
5285 	len = sizeof(int);
5286 
5287 	val = sctp_sk(sk)->frag_interleave;
5288 	if (put_user(len, optlen))
5289 		return -EFAULT;
5290 	if (copy_to_user(optval, &val, len))
5291 		return -EFAULT;
5292 
5293 	return 0;
5294 }
5295 
5296 /*
5297  * 7.1.25.  Set or Get the sctp partial delivery point
5298  * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
5299  */
5300 static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
5301 						  char __user *optval,
5302 						  int __user *optlen)
5303 {
5304 	u32 val;
5305 
5306 	if (len < sizeof(u32))
5307 		return -EINVAL;
5308 
5309 	len = sizeof(u32);
5310 
5311 	val = sctp_sk(sk)->pd_point;
5312 	if (put_user(len, optlen))
5313 		return -EFAULT;
5314 	if (copy_to_user(optval, &val, len))
5315 		return -EFAULT;
5316 
5317 	return -ENOTSUPP;
5318 }
5319 
5320 /*
5321  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
5322  * (chapter and verse is quoted at sctp_setsockopt_maxburst())
5323  */
5324 static int sctp_getsockopt_maxburst(struct sock *sk, int len,
5325 				    char __user *optval,
5326 				    int __user *optlen)
5327 {
5328 	struct sctp_assoc_value params;
5329 	struct sctp_sock *sp;
5330 	struct sctp_association *asoc;
5331 
5332 	if (len == sizeof(int)) {
5333 		printk(KERN_WARNING
5334 		   "SCTP: Use of int in max_burst socket option deprecated\n");
5335 		printk(KERN_WARNING
5336 		   "SCTP: Use struct sctp_assoc_value instead\n");
5337 		params.assoc_id = 0;
5338 	} else if (len >= sizeof(struct sctp_assoc_value)) {
5339 		len = sizeof(struct sctp_assoc_value);
5340 		if (copy_from_user(&params, optval, len))
5341 			return -EFAULT;
5342 	} else
5343 		return -EINVAL;
5344 
5345 	sp = sctp_sk(sk);
5346 
5347 	if (params.assoc_id != 0) {
5348 		asoc = sctp_id2assoc(sk, params.assoc_id);
5349 		if (!asoc)
5350 			return -EINVAL;
5351 		params.assoc_value = asoc->max_burst;
5352 	} else
5353 		params.assoc_value = sp->max_burst;
5354 
5355 	if (len == sizeof(int)) {
5356 		if (copy_to_user(optval, &params.assoc_value, len))
5357 			return -EFAULT;
5358 	} else {
5359 		if (copy_to_user(optval, &params, len))
5360 			return -EFAULT;
5361 	}
5362 
5363 	return 0;
5364 
5365 }
5366 
5367 static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
5368 				    char __user *optval, int __user *optlen)
5369 {
5370 	struct sctp_hmacalgo  __user *p = (void __user *)optval;
5371 	struct sctp_hmac_algo_param *hmacs;
5372 	__u16 data_len = 0;
5373 	u32 num_idents;
5374 
5375 	if (!sctp_auth_enable)
5376 		return -EACCES;
5377 
5378 	hmacs = sctp_sk(sk)->ep->auth_hmacs_list;
5379 	data_len = ntohs(hmacs->param_hdr.length) - sizeof(sctp_paramhdr_t);
5380 
5381 	if (len < sizeof(struct sctp_hmacalgo) + data_len)
5382 		return -EINVAL;
5383 
5384 	len = sizeof(struct sctp_hmacalgo) + data_len;
5385 	num_idents = data_len / sizeof(u16);
5386 
5387 	if (put_user(len, optlen))
5388 		return -EFAULT;
5389 	if (put_user(num_idents, &p->shmac_num_idents))
5390 		return -EFAULT;
5391 	if (copy_to_user(p->shmac_idents, hmacs->hmac_ids, data_len))
5392 		return -EFAULT;
5393 	return 0;
5394 }
5395 
5396 static int sctp_getsockopt_active_key(struct sock *sk, int len,
5397 				    char __user *optval, int __user *optlen)
5398 {
5399 	struct sctp_authkeyid val;
5400 	struct sctp_association *asoc;
5401 
5402 	if (!sctp_auth_enable)
5403 		return -EACCES;
5404 
5405 	if (len < sizeof(struct sctp_authkeyid))
5406 		return -EINVAL;
5407 	if (copy_from_user(&val, optval, sizeof(struct sctp_authkeyid)))
5408 		return -EFAULT;
5409 
5410 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
5411 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
5412 		return -EINVAL;
5413 
5414 	if (asoc)
5415 		val.scact_keynumber = asoc->active_key_id;
5416 	else
5417 		val.scact_keynumber = sctp_sk(sk)->ep->active_key_id;
5418 
5419 	len = sizeof(struct sctp_authkeyid);
5420 	if (put_user(len, optlen))
5421 		return -EFAULT;
5422 	if (copy_to_user(optval, &val, len))
5423 		return -EFAULT;
5424 
5425 	return 0;
5426 }
5427 
5428 static int sctp_getsockopt_peer_auth_chunks(struct sock *sk, int len,
5429 				    char __user *optval, int __user *optlen)
5430 {
5431 	struct sctp_authchunks __user *p = (void __user *)optval;
5432 	struct sctp_authchunks val;
5433 	struct sctp_association *asoc;
5434 	struct sctp_chunks_param *ch;
5435 	u32    num_chunks = 0;
5436 	char __user *to;
5437 
5438 	if (!sctp_auth_enable)
5439 		return -EACCES;
5440 
5441 	if (len < sizeof(struct sctp_authchunks))
5442 		return -EINVAL;
5443 
5444 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5445 		return -EFAULT;
5446 
5447 	to = p->gauth_chunks;
5448 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5449 	if (!asoc)
5450 		return -EINVAL;
5451 
5452 	ch = asoc->peer.peer_chunks;
5453 	if (!ch)
5454 		goto num;
5455 
5456 	/* See if the user provided enough room for all the data */
5457 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5458 	if (len < num_chunks)
5459 		return -EINVAL;
5460 
5461 	if (copy_to_user(to, ch->chunks, num_chunks))
5462 		return -EFAULT;
5463 num:
5464 	len = sizeof(struct sctp_authchunks) + num_chunks;
5465 	if (put_user(len, optlen)) return -EFAULT;
5466 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
5467 		return -EFAULT;
5468 	return 0;
5469 }
5470 
5471 static int sctp_getsockopt_local_auth_chunks(struct sock *sk, int len,
5472 				    char __user *optval, int __user *optlen)
5473 {
5474 	struct sctp_authchunks __user *p = (void __user *)optval;
5475 	struct sctp_authchunks val;
5476 	struct sctp_association *asoc;
5477 	struct sctp_chunks_param *ch;
5478 	u32    num_chunks = 0;
5479 	char __user *to;
5480 
5481 	if (!sctp_auth_enable)
5482 		return -EACCES;
5483 
5484 	if (len < sizeof(struct sctp_authchunks))
5485 		return -EINVAL;
5486 
5487 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5488 		return -EFAULT;
5489 
5490 	to = p->gauth_chunks;
5491 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5492 	if (!asoc && val.gauth_assoc_id && sctp_style(sk, UDP))
5493 		return -EINVAL;
5494 
5495 	if (asoc)
5496 		ch = (struct sctp_chunks_param*)asoc->c.auth_chunks;
5497 	else
5498 		ch = sctp_sk(sk)->ep->auth_chunk_list;
5499 
5500 	if (!ch)
5501 		goto num;
5502 
5503 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5504 	if (len < sizeof(struct sctp_authchunks) + num_chunks)
5505 		return -EINVAL;
5506 
5507 	if (copy_to_user(to, ch->chunks, num_chunks))
5508 		return -EFAULT;
5509 num:
5510 	len = sizeof(struct sctp_authchunks) + num_chunks;
5511 	if (put_user(len, optlen))
5512 		return -EFAULT;
5513 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
5514 		return -EFAULT;
5515 
5516 	return 0;
5517 }
5518 
5519 /*
5520  * 8.2.5.  Get the Current Number of Associations (SCTP_GET_ASSOC_NUMBER)
5521  * This option gets the current number of associations that are attached
5522  * to a one-to-many style socket.  The option value is an uint32_t.
5523  */
5524 static int sctp_getsockopt_assoc_number(struct sock *sk, int len,
5525 				    char __user *optval, int __user *optlen)
5526 {
5527 	struct sctp_sock *sp = sctp_sk(sk);
5528 	struct sctp_association *asoc;
5529 	u32 val = 0;
5530 
5531 	if (sctp_style(sk, TCP))
5532 		return -EOPNOTSUPP;
5533 
5534 	if (len < sizeof(u32))
5535 		return -EINVAL;
5536 
5537 	len = sizeof(u32);
5538 
5539 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
5540 		val++;
5541 	}
5542 
5543 	if (put_user(len, optlen))
5544 		return -EFAULT;
5545 	if (copy_to_user(optval, &val, len))
5546 		return -EFAULT;
5547 
5548 	return 0;
5549 }
5550 
5551 SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
5552 				char __user *optval, int __user *optlen)
5553 {
5554 	int retval = 0;
5555 	int len;
5556 
5557 	SCTP_DEBUG_PRINTK("sctp_getsockopt(sk: %p... optname: %d)\n",
5558 			  sk, optname);
5559 
5560 	/* I can hardly begin to describe how wrong this is.  This is
5561 	 * so broken as to be worse than useless.  The API draft
5562 	 * REALLY is NOT helpful here...  I am not convinced that the
5563 	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
5564 	 * are at all well-founded.
5565 	 */
5566 	if (level != SOL_SCTP) {
5567 		struct sctp_af *af = sctp_sk(sk)->pf->af;
5568 
5569 		retval = af->getsockopt(sk, level, optname, optval, optlen);
5570 		return retval;
5571 	}
5572 
5573 	if (get_user(len, optlen))
5574 		return -EFAULT;
5575 
5576 	sctp_lock_sock(sk);
5577 
5578 	switch (optname) {
5579 	case SCTP_STATUS:
5580 		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
5581 		break;
5582 	case SCTP_DISABLE_FRAGMENTS:
5583 		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
5584 							   optlen);
5585 		break;
5586 	case SCTP_EVENTS:
5587 		retval = sctp_getsockopt_events(sk, len, optval, optlen);
5588 		break;
5589 	case SCTP_AUTOCLOSE:
5590 		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
5591 		break;
5592 	case SCTP_SOCKOPT_PEELOFF:
5593 		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
5594 		break;
5595 	case SCTP_PEER_ADDR_PARAMS:
5596 		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
5597 							  optlen);
5598 		break;
5599 	case SCTP_DELAYED_ACK:
5600 		retval = sctp_getsockopt_delayed_ack(sk, len, optval,
5601 							  optlen);
5602 		break;
5603 	case SCTP_INITMSG:
5604 		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
5605 		break;
5606 	case SCTP_GET_PEER_ADDRS_NUM_OLD:
5607 		retval = sctp_getsockopt_peer_addrs_num_old(sk, len, optval,
5608 							    optlen);
5609 		break;
5610 	case SCTP_GET_LOCAL_ADDRS_NUM_OLD:
5611 		retval = sctp_getsockopt_local_addrs_num_old(sk, len, optval,
5612 							     optlen);
5613 		break;
5614 	case SCTP_GET_PEER_ADDRS_OLD:
5615 		retval = sctp_getsockopt_peer_addrs_old(sk, len, optval,
5616 							optlen);
5617 		break;
5618 	case SCTP_GET_LOCAL_ADDRS_OLD:
5619 		retval = sctp_getsockopt_local_addrs_old(sk, len, optval,
5620 							 optlen);
5621 		break;
5622 	case SCTP_GET_PEER_ADDRS:
5623 		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
5624 						    optlen);
5625 		break;
5626 	case SCTP_GET_LOCAL_ADDRS:
5627 		retval = sctp_getsockopt_local_addrs(sk, len, optval,
5628 						     optlen);
5629 		break;
5630 	case SCTP_SOCKOPT_CONNECTX3:
5631 		retval = sctp_getsockopt_connectx3(sk, len, optval, optlen);
5632 		break;
5633 	case SCTP_DEFAULT_SEND_PARAM:
5634 		retval = sctp_getsockopt_default_send_param(sk, len,
5635 							    optval, optlen);
5636 		break;
5637 	case SCTP_PRIMARY_ADDR:
5638 		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
5639 		break;
5640 	case SCTP_NODELAY:
5641 		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
5642 		break;
5643 	case SCTP_RTOINFO:
5644 		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
5645 		break;
5646 	case SCTP_ASSOCINFO:
5647 		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
5648 		break;
5649 	case SCTP_I_WANT_MAPPED_V4_ADDR:
5650 		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
5651 		break;
5652 	case SCTP_MAXSEG:
5653 		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
5654 		break;
5655 	case SCTP_GET_PEER_ADDR_INFO:
5656 		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
5657 							optlen);
5658 		break;
5659 	case SCTP_ADAPTATION_LAYER:
5660 		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
5661 							optlen);
5662 		break;
5663 	case SCTP_CONTEXT:
5664 		retval = sctp_getsockopt_context(sk, len, optval, optlen);
5665 		break;
5666 	case SCTP_FRAGMENT_INTERLEAVE:
5667 		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
5668 							     optlen);
5669 		break;
5670 	case SCTP_PARTIAL_DELIVERY_POINT:
5671 		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
5672 								optlen);
5673 		break;
5674 	case SCTP_MAX_BURST:
5675 		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
5676 		break;
5677 	case SCTP_AUTH_KEY:
5678 	case SCTP_AUTH_CHUNK:
5679 	case SCTP_AUTH_DELETE_KEY:
5680 		retval = -EOPNOTSUPP;
5681 		break;
5682 	case SCTP_HMAC_IDENT:
5683 		retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
5684 		break;
5685 	case SCTP_AUTH_ACTIVE_KEY:
5686 		retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
5687 		break;
5688 	case SCTP_PEER_AUTH_CHUNKS:
5689 		retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
5690 							optlen);
5691 		break;
5692 	case SCTP_LOCAL_AUTH_CHUNKS:
5693 		retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
5694 							optlen);
5695 		break;
5696 	case SCTP_GET_ASSOC_NUMBER:
5697 		retval = sctp_getsockopt_assoc_number(sk, len, optval, optlen);
5698 		break;
5699 	default:
5700 		retval = -ENOPROTOOPT;
5701 		break;
5702 	}
5703 
5704 	sctp_release_sock(sk);
5705 	return retval;
5706 }
5707 
5708 static void sctp_hash(struct sock *sk)
5709 {
5710 	/* STUB */
5711 }
5712 
5713 static void sctp_unhash(struct sock *sk)
5714 {
5715 	/* STUB */
5716 }
5717 
5718 /* Check if port is acceptable.  Possibly find first available port.
5719  *
5720  * The port hash table (contained in the 'global' SCTP protocol storage
5721  * returned by struct sctp_protocol *sctp_get_protocol()). The hash
5722  * table is an array of 4096 lists (sctp_bind_hashbucket). Each
5723  * list (the list number is the port number hashed out, so as you
5724  * would expect from a hash function, all the ports in a given list have
5725  * such a number that hashes out to the same list number; you were
5726  * expecting that, right?); so each list has a set of ports, with a
5727  * link to the socket (struct sock) that uses it, the port number and
5728  * a fastreuse flag (FIXME: NPI ipg).
5729  */
5730 static struct sctp_bind_bucket *sctp_bucket_create(
5731 	struct sctp_bind_hashbucket *head, unsigned short snum);
5732 
5733 static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
5734 {
5735 	struct sctp_bind_hashbucket *head; /* hash list */
5736 	struct sctp_bind_bucket *pp; /* hash list port iterator */
5737 	struct hlist_node *node;
5738 	unsigned short snum;
5739 	int ret;
5740 
5741 	snum = ntohs(addr->v4.sin_port);
5742 
5743 	SCTP_DEBUG_PRINTK("sctp_get_port() begins, snum=%d\n", snum);
5744 	sctp_local_bh_disable();
5745 
5746 	if (snum == 0) {
5747 		/* Search for an available port. */
5748 		int low, high, remaining, index;
5749 		unsigned int rover;
5750 
5751 		inet_get_local_port_range(&low, &high);
5752 		remaining = (high - low) + 1;
5753 		rover = net_random() % remaining + low;
5754 
5755 		do {
5756 			rover++;
5757 			if ((rover < low) || (rover > high))
5758 				rover = low;
5759 			index = sctp_phashfn(rover);
5760 			head = &sctp_port_hashtable[index];
5761 			sctp_spin_lock(&head->lock);
5762 			sctp_for_each_hentry(pp, node, &head->chain)
5763 				if (pp->port == rover)
5764 					goto next;
5765 			break;
5766 		next:
5767 			sctp_spin_unlock(&head->lock);
5768 		} while (--remaining > 0);
5769 
5770 		/* Exhausted local port range during search? */
5771 		ret = 1;
5772 		if (remaining <= 0)
5773 			goto fail;
5774 
5775 		/* OK, here is the one we will use.  HEAD (the port
5776 		 * hash table list entry) is non-NULL and we hold it's
5777 		 * mutex.
5778 		 */
5779 		snum = rover;
5780 	} else {
5781 		/* We are given an specific port number; we verify
5782 		 * that it is not being used. If it is used, we will
5783 		 * exahust the search in the hash list corresponding
5784 		 * to the port number (snum) - we detect that with the
5785 		 * port iterator, pp being NULL.
5786 		 */
5787 		head = &sctp_port_hashtable[sctp_phashfn(snum)];
5788 		sctp_spin_lock(&head->lock);
5789 		sctp_for_each_hentry(pp, node, &head->chain) {
5790 			if (pp->port == snum)
5791 				goto pp_found;
5792 		}
5793 	}
5794 	pp = NULL;
5795 	goto pp_not_found;
5796 pp_found:
5797 	if (!hlist_empty(&pp->owner)) {
5798 		/* We had a port hash table hit - there is an
5799 		 * available port (pp != NULL) and it is being
5800 		 * used by other socket (pp->owner not empty); that other
5801 		 * socket is going to be sk2.
5802 		 */
5803 		int reuse = sk->sk_reuse;
5804 		struct sock *sk2;
5805 		struct hlist_node *node;
5806 
5807 		SCTP_DEBUG_PRINTK("sctp_get_port() found a possible match\n");
5808 		if (pp->fastreuse && sk->sk_reuse &&
5809 			sk->sk_state != SCTP_SS_LISTENING)
5810 			goto success;
5811 
5812 		/* Run through the list of sockets bound to the port
5813 		 * (pp->port) [via the pointers bind_next and
5814 		 * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
5815 		 * we get the endpoint they describe and run through
5816 		 * the endpoint's list of IP (v4 or v6) addresses,
5817 		 * comparing each of the addresses with the address of
5818 		 * the socket sk. If we find a match, then that means
5819 		 * that this port/socket (sk) combination are already
5820 		 * in an endpoint.
5821 		 */
5822 		sk_for_each_bound(sk2, node, &pp->owner) {
5823 			struct sctp_endpoint *ep2;
5824 			ep2 = sctp_sk(sk2)->ep;
5825 
5826 			if (sk == sk2 ||
5827 			    (reuse && sk2->sk_reuse &&
5828 			     sk2->sk_state != SCTP_SS_LISTENING))
5829 				continue;
5830 
5831 			if (sctp_bind_addr_conflict(&ep2->base.bind_addr, addr,
5832 						 sctp_sk(sk2), sctp_sk(sk))) {
5833 				ret = (long)sk2;
5834 				goto fail_unlock;
5835 			}
5836 		}
5837 		SCTP_DEBUG_PRINTK("sctp_get_port(): Found a match\n");
5838 	}
5839 pp_not_found:
5840 	/* If there was a hash table miss, create a new port.  */
5841 	ret = 1;
5842 	if (!pp && !(pp = sctp_bucket_create(head, snum)))
5843 		goto fail_unlock;
5844 
5845 	/* In either case (hit or miss), make sure fastreuse is 1 only
5846 	 * if sk->sk_reuse is too (that is, if the caller requested
5847 	 * SO_REUSEADDR on this socket -sk-).
5848 	 */
5849 	if (hlist_empty(&pp->owner)) {
5850 		if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
5851 			pp->fastreuse = 1;
5852 		else
5853 			pp->fastreuse = 0;
5854 	} else if (pp->fastreuse &&
5855 		(!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
5856 		pp->fastreuse = 0;
5857 
5858 	/* We are set, so fill up all the data in the hash table
5859 	 * entry, tie the socket list information with the rest of the
5860 	 * sockets FIXME: Blurry, NPI (ipg).
5861 	 */
5862 success:
5863 	if (!sctp_sk(sk)->bind_hash) {
5864 		inet_sk(sk)->num = snum;
5865 		sk_add_bind_node(sk, &pp->owner);
5866 		sctp_sk(sk)->bind_hash = pp;
5867 	}
5868 	ret = 0;
5869 
5870 fail_unlock:
5871 	sctp_spin_unlock(&head->lock);
5872 
5873 fail:
5874 	sctp_local_bh_enable();
5875 	return ret;
5876 }
5877 
5878 /* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
5879  * port is requested.
5880  */
5881 static int sctp_get_port(struct sock *sk, unsigned short snum)
5882 {
5883 	long ret;
5884 	union sctp_addr addr;
5885 	struct sctp_af *af = sctp_sk(sk)->pf->af;
5886 
5887 	/* Set up a dummy address struct from the sk. */
5888 	af->from_sk(&addr, sk);
5889 	addr.v4.sin_port = htons(snum);
5890 
5891 	/* Note: sk->sk_num gets filled in if ephemeral port request. */
5892 	ret = sctp_get_port_local(sk, &addr);
5893 
5894 	return (ret ? 1 : 0);
5895 }
5896 
5897 /*
5898  *  Move a socket to LISTENING state.
5899  */
5900 SCTP_STATIC int sctp_listen_start(struct sock *sk, int backlog)
5901 {
5902 	struct sctp_sock *sp = sctp_sk(sk);
5903 	struct sctp_endpoint *ep = sp->ep;
5904 	struct crypto_hash *tfm = NULL;
5905 
5906 	/* Allocate HMAC for generating cookie. */
5907 	if (!sctp_sk(sk)->hmac && sctp_hmac_alg) {
5908 		tfm = crypto_alloc_hash(sctp_hmac_alg, 0, CRYPTO_ALG_ASYNC);
5909 		if (IS_ERR(tfm)) {
5910 			if (net_ratelimit()) {
5911 				printk(KERN_INFO
5912 				       "SCTP: failed to load transform for %s: %ld\n",
5913 					sctp_hmac_alg, PTR_ERR(tfm));
5914 			}
5915 			return -ENOSYS;
5916 		}
5917 		sctp_sk(sk)->hmac = tfm;
5918 	}
5919 
5920 	/*
5921 	 * If a bind() or sctp_bindx() is not called prior to a listen()
5922 	 * call that allows new associations to be accepted, the system
5923 	 * picks an ephemeral port and will choose an address set equivalent
5924 	 * to binding with a wildcard address.
5925 	 *
5926 	 * This is not currently spelled out in the SCTP sockets
5927 	 * extensions draft, but follows the practice as seen in TCP
5928 	 * sockets.
5929 	 *
5930 	 */
5931 	sk->sk_state = SCTP_SS_LISTENING;
5932 	if (!ep->base.bind_addr.port) {
5933 		if (sctp_autobind(sk))
5934 			return -EAGAIN;
5935 	} else {
5936 		if (sctp_get_port(sk, inet_sk(sk)->num)) {
5937 			sk->sk_state = SCTP_SS_CLOSED;
5938 			return -EADDRINUSE;
5939 		}
5940 	}
5941 
5942 	sk->sk_max_ack_backlog = backlog;
5943 	sctp_hash_endpoint(ep);
5944 	return 0;
5945 }
5946 
5947 /*
5948  * 4.1.3 / 5.1.3 listen()
5949  *
5950  *   By default, new associations are not accepted for UDP style sockets.
5951  *   An application uses listen() to mark a socket as being able to
5952  *   accept new associations.
5953  *
5954  *   On TCP style sockets, applications use listen() to ready the SCTP
5955  *   endpoint for accepting inbound associations.
5956  *
5957  *   On both types of endpoints a backlog of '0' disables listening.
5958  *
5959  *  Move a socket to LISTENING state.
5960  */
5961 int sctp_inet_listen(struct socket *sock, int backlog)
5962 {
5963 	struct sock *sk = sock->sk;
5964 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5965 	int err = -EINVAL;
5966 
5967 	if (unlikely(backlog < 0))
5968 		return err;
5969 
5970 	sctp_lock_sock(sk);
5971 
5972 	/* Peeled-off sockets are not allowed to listen().  */
5973 	if (sctp_style(sk, UDP_HIGH_BANDWIDTH))
5974 		goto out;
5975 
5976 	if (sock->state != SS_UNCONNECTED)
5977 		goto out;
5978 
5979 	/* If backlog is zero, disable listening. */
5980 	if (!backlog) {
5981 		if (sctp_sstate(sk, CLOSED))
5982 			goto out;
5983 
5984 		err = 0;
5985 		sctp_unhash_endpoint(ep);
5986 		sk->sk_state = SCTP_SS_CLOSED;
5987 		if (sk->sk_reuse)
5988 			sctp_sk(sk)->bind_hash->fastreuse = 1;
5989 		goto out;
5990 	}
5991 
5992 	/* If we are already listening, just update the backlog */
5993 	if (sctp_sstate(sk, LISTENING))
5994 		sk->sk_max_ack_backlog = backlog;
5995 	else {
5996 		err = sctp_listen_start(sk, backlog);
5997 		if (err)
5998 			goto out;
5999 	}
6000 
6001 	err = 0;
6002 out:
6003 	sctp_release_sock(sk);
6004 	return err;
6005 }
6006 
6007 /*
6008  * This function is done by modeling the current datagram_poll() and the
6009  * tcp_poll().  Note that, based on these implementations, we don't
6010  * lock the socket in this function, even though it seems that,
6011  * ideally, locking or some other mechanisms can be used to ensure
6012  * the integrity of the counters (sndbuf and wmem_alloc) used
6013  * in this place.  We assume that we don't need locks either until proven
6014  * otherwise.
6015  *
6016  * Another thing to note is that we include the Async I/O support
6017  * here, again, by modeling the current TCP/UDP code.  We don't have
6018  * a good way to test with it yet.
6019  */
6020 unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
6021 {
6022 	struct sock *sk = sock->sk;
6023 	struct sctp_sock *sp = sctp_sk(sk);
6024 	unsigned int mask;
6025 
6026 	poll_wait(file, sk->sk_sleep, wait);
6027 
6028 	/* A TCP-style listening socket becomes readable when the accept queue
6029 	 * is not empty.
6030 	 */
6031 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
6032 		return (!list_empty(&sp->ep->asocs)) ?
6033 			(POLLIN | POLLRDNORM) : 0;
6034 
6035 	mask = 0;
6036 
6037 	/* Is there any exceptional events?  */
6038 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
6039 		mask |= POLLERR;
6040 	if (sk->sk_shutdown & RCV_SHUTDOWN)
6041 		mask |= POLLRDHUP;
6042 	if (sk->sk_shutdown == SHUTDOWN_MASK)
6043 		mask |= POLLHUP;
6044 
6045 	/* Is it readable?  Reconsider this code with TCP-style support.  */
6046 	if (!skb_queue_empty(&sk->sk_receive_queue) ||
6047 	    (sk->sk_shutdown & RCV_SHUTDOWN))
6048 		mask |= POLLIN | POLLRDNORM;
6049 
6050 	/* The association is either gone or not ready.  */
6051 	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
6052 		return mask;
6053 
6054 	/* Is it writable?  */
6055 	if (sctp_writeable(sk)) {
6056 		mask |= POLLOUT | POLLWRNORM;
6057 	} else {
6058 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
6059 		/*
6060 		 * Since the socket is not locked, the buffer
6061 		 * might be made available after the writeable check and
6062 		 * before the bit is set.  This could cause a lost I/O
6063 		 * signal.  tcp_poll() has a race breaker for this race
6064 		 * condition.  Based on their implementation, we put
6065 		 * in the following code to cover it as well.
6066 		 */
6067 		if (sctp_writeable(sk))
6068 			mask |= POLLOUT | POLLWRNORM;
6069 	}
6070 	return mask;
6071 }
6072 
6073 /********************************************************************
6074  * 2nd Level Abstractions
6075  ********************************************************************/
6076 
6077 static struct sctp_bind_bucket *sctp_bucket_create(
6078 	struct sctp_bind_hashbucket *head, unsigned short snum)
6079 {
6080 	struct sctp_bind_bucket *pp;
6081 
6082 	pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
6083 	if (pp) {
6084 		SCTP_DBG_OBJCNT_INC(bind_bucket);
6085 		pp->port = snum;
6086 		pp->fastreuse = 0;
6087 		INIT_HLIST_HEAD(&pp->owner);
6088 		hlist_add_head(&pp->node, &head->chain);
6089 	}
6090 	return pp;
6091 }
6092 
6093 /* Caller must hold hashbucket lock for this tb with local BH disabled */
6094 static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
6095 {
6096 	if (pp && hlist_empty(&pp->owner)) {
6097 		__hlist_del(&pp->node);
6098 		kmem_cache_free(sctp_bucket_cachep, pp);
6099 		SCTP_DBG_OBJCNT_DEC(bind_bucket);
6100 	}
6101 }
6102 
6103 /* Release this socket's reference to a local port.  */
6104 static inline void __sctp_put_port(struct sock *sk)
6105 {
6106 	struct sctp_bind_hashbucket *head =
6107 		&sctp_port_hashtable[sctp_phashfn(inet_sk(sk)->num)];
6108 	struct sctp_bind_bucket *pp;
6109 
6110 	sctp_spin_lock(&head->lock);
6111 	pp = sctp_sk(sk)->bind_hash;
6112 	__sk_del_bind_node(sk);
6113 	sctp_sk(sk)->bind_hash = NULL;
6114 	inet_sk(sk)->num = 0;
6115 	sctp_bucket_destroy(pp);
6116 	sctp_spin_unlock(&head->lock);
6117 }
6118 
6119 void sctp_put_port(struct sock *sk)
6120 {
6121 	sctp_local_bh_disable();
6122 	__sctp_put_port(sk);
6123 	sctp_local_bh_enable();
6124 }
6125 
6126 /*
6127  * The system picks an ephemeral port and choose an address set equivalent
6128  * to binding with a wildcard address.
6129  * One of those addresses will be the primary address for the association.
6130  * This automatically enables the multihoming capability of SCTP.
6131  */
6132 static int sctp_autobind(struct sock *sk)
6133 {
6134 	union sctp_addr autoaddr;
6135 	struct sctp_af *af;
6136 	__be16 port;
6137 
6138 	/* Initialize a local sockaddr structure to INADDR_ANY. */
6139 	af = sctp_sk(sk)->pf->af;
6140 
6141 	port = htons(inet_sk(sk)->num);
6142 	af->inaddr_any(&autoaddr, port);
6143 
6144 	return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
6145 }
6146 
6147 /* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
6148  *
6149  * From RFC 2292
6150  * 4.2 The cmsghdr Structure *
6151  *
6152  * When ancillary data is sent or received, any number of ancillary data
6153  * objects can be specified by the msg_control and msg_controllen members of
6154  * the msghdr structure, because each object is preceded by
6155  * a cmsghdr structure defining the object's length (the cmsg_len member).
6156  * Historically Berkeley-derived implementations have passed only one object
6157  * at a time, but this API allows multiple objects to be
6158  * passed in a single call to sendmsg() or recvmsg(). The following example
6159  * shows two ancillary data objects in a control buffer.
6160  *
6161  *   |<--------------------------- msg_controllen -------------------------->|
6162  *   |                                                                       |
6163  *
6164  *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
6165  *
6166  *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
6167  *   |                                   |                                   |
6168  *
6169  *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
6170  *
6171  *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
6172  *   |                                |  |                                |  |
6173  *
6174  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
6175  *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
6176  *
6177  *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
6178  *
6179  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
6180  *    ^
6181  *    |
6182  *
6183  * msg_control
6184  * points here
6185  */
6186 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *msg,
6187 				  sctp_cmsgs_t *cmsgs)
6188 {
6189 	struct cmsghdr *cmsg;
6190 	struct msghdr *my_msg = (struct msghdr *)msg;
6191 
6192 	for (cmsg = CMSG_FIRSTHDR(msg);
6193 	     cmsg != NULL;
6194 	     cmsg = CMSG_NXTHDR(my_msg, cmsg)) {
6195 		if (!CMSG_OK(my_msg, cmsg))
6196 			return -EINVAL;
6197 
6198 		/* Should we parse this header or ignore?  */
6199 		if (cmsg->cmsg_level != IPPROTO_SCTP)
6200 			continue;
6201 
6202 		/* Strictly check lengths following example in SCM code.  */
6203 		switch (cmsg->cmsg_type) {
6204 		case SCTP_INIT:
6205 			/* SCTP Socket API Extension
6206 			 * 5.2.1 SCTP Initiation Structure (SCTP_INIT)
6207 			 *
6208 			 * This cmsghdr structure provides information for
6209 			 * initializing new SCTP associations with sendmsg().
6210 			 * The SCTP_INITMSG socket option uses this same data
6211 			 * structure.  This structure is not used for
6212 			 * recvmsg().
6213 			 *
6214 			 * cmsg_level    cmsg_type      cmsg_data[]
6215 			 * ------------  ------------   ----------------------
6216 			 * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
6217 			 */
6218 			if (cmsg->cmsg_len !=
6219 			    CMSG_LEN(sizeof(struct sctp_initmsg)))
6220 				return -EINVAL;
6221 			cmsgs->init = (struct sctp_initmsg *)CMSG_DATA(cmsg);
6222 			break;
6223 
6224 		case SCTP_SNDRCV:
6225 			/* SCTP Socket API Extension
6226 			 * 5.2.2 SCTP Header Information Structure(SCTP_SNDRCV)
6227 			 *
6228 			 * This cmsghdr structure specifies SCTP options for
6229 			 * sendmsg() and describes SCTP header information
6230 			 * about a received message through recvmsg().
6231 			 *
6232 			 * cmsg_level    cmsg_type      cmsg_data[]
6233 			 * ------------  ------------   ----------------------
6234 			 * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
6235 			 */
6236 			if (cmsg->cmsg_len !=
6237 			    CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
6238 				return -EINVAL;
6239 
6240 			cmsgs->info =
6241 				(struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
6242 
6243 			/* Minimally, validate the sinfo_flags. */
6244 			if (cmsgs->info->sinfo_flags &
6245 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
6246 			      SCTP_ABORT | SCTP_EOF))
6247 				return -EINVAL;
6248 			break;
6249 
6250 		default:
6251 			return -EINVAL;
6252 		}
6253 	}
6254 	return 0;
6255 }
6256 
6257 /*
6258  * Wait for a packet..
6259  * Note: This function is the same function as in core/datagram.c
6260  * with a few modifications to make lksctp work.
6261  */
6262 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p)
6263 {
6264 	int error;
6265 	DEFINE_WAIT(wait);
6266 
6267 	prepare_to_wait_exclusive(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
6268 
6269 	/* Socket errors? */
6270 	error = sock_error(sk);
6271 	if (error)
6272 		goto out;
6273 
6274 	if (!skb_queue_empty(&sk->sk_receive_queue))
6275 		goto ready;
6276 
6277 	/* Socket shut down?  */
6278 	if (sk->sk_shutdown & RCV_SHUTDOWN)
6279 		goto out;
6280 
6281 	/* Sequenced packets can come disconnected.  If so we report the
6282 	 * problem.
6283 	 */
6284 	error = -ENOTCONN;
6285 
6286 	/* Is there a good reason to think that we may receive some data?  */
6287 	if (list_empty(&sctp_sk(sk)->ep->asocs) && !sctp_sstate(sk, LISTENING))
6288 		goto out;
6289 
6290 	/* Handle signals.  */
6291 	if (signal_pending(current))
6292 		goto interrupted;
6293 
6294 	/* Let another process have a go.  Since we are going to sleep
6295 	 * anyway.  Note: This may cause odd behaviors if the message
6296 	 * does not fit in the user's buffer, but this seems to be the
6297 	 * only way to honor MSG_DONTWAIT realistically.
6298 	 */
6299 	sctp_release_sock(sk);
6300 	*timeo_p = schedule_timeout(*timeo_p);
6301 	sctp_lock_sock(sk);
6302 
6303 ready:
6304 	finish_wait(sk->sk_sleep, &wait);
6305 	return 0;
6306 
6307 interrupted:
6308 	error = sock_intr_errno(*timeo_p);
6309 
6310 out:
6311 	finish_wait(sk->sk_sleep, &wait);
6312 	*err = error;
6313 	return error;
6314 }
6315 
6316 /* Receive a datagram.
6317  * Note: This is pretty much the same routine as in core/datagram.c
6318  * with a few changes to make lksctp work.
6319  */
6320 static struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
6321 					      int noblock, int *err)
6322 {
6323 	int error;
6324 	struct sk_buff *skb;
6325 	long timeo;
6326 
6327 	timeo = sock_rcvtimeo(sk, noblock);
6328 
6329 	SCTP_DEBUG_PRINTK("Timeout: timeo: %ld, MAX: %ld.\n",
6330 			  timeo, MAX_SCHEDULE_TIMEOUT);
6331 
6332 	do {
6333 		/* Again only user level code calls this function,
6334 		 * so nothing interrupt level
6335 		 * will suddenly eat the receive_queue.
6336 		 *
6337 		 *  Look at current nfs client by the way...
6338 		 *  However, this function was corrent in any case. 8)
6339 		 */
6340 		if (flags & MSG_PEEK) {
6341 			spin_lock_bh(&sk->sk_receive_queue.lock);
6342 			skb = skb_peek(&sk->sk_receive_queue);
6343 			if (skb)
6344 				atomic_inc(&skb->users);
6345 			spin_unlock_bh(&sk->sk_receive_queue.lock);
6346 		} else {
6347 			skb = skb_dequeue(&sk->sk_receive_queue);
6348 		}
6349 
6350 		if (skb)
6351 			return skb;
6352 
6353 		/* Caller is allowed not to check sk->sk_err before calling. */
6354 		error = sock_error(sk);
6355 		if (error)
6356 			goto no_packet;
6357 
6358 		if (sk->sk_shutdown & RCV_SHUTDOWN)
6359 			break;
6360 
6361 		/* User doesn't want to wait.  */
6362 		error = -EAGAIN;
6363 		if (!timeo)
6364 			goto no_packet;
6365 	} while (sctp_wait_for_packet(sk, err, &timeo) == 0);
6366 
6367 	return NULL;
6368 
6369 no_packet:
6370 	*err = error;
6371 	return NULL;
6372 }
6373 
6374 /* If sndbuf has changed, wake up per association sndbuf waiters.  */
6375 static void __sctp_write_space(struct sctp_association *asoc)
6376 {
6377 	struct sock *sk = asoc->base.sk;
6378 	struct socket *sock = sk->sk_socket;
6379 
6380 	if ((sctp_wspace(asoc) > 0) && sock) {
6381 		if (waitqueue_active(&asoc->wait))
6382 			wake_up_interruptible(&asoc->wait);
6383 
6384 		if (sctp_writeable(sk)) {
6385 			if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
6386 				wake_up_interruptible(sk->sk_sleep);
6387 
6388 			/* Note that we try to include the Async I/O support
6389 			 * here by modeling from the current TCP/UDP code.
6390 			 * We have not tested with it yet.
6391 			 */
6392 			if (sock->fasync_list &&
6393 			    !(sk->sk_shutdown & SEND_SHUTDOWN))
6394 				sock_wake_async(sock,
6395 						SOCK_WAKE_SPACE, POLL_OUT);
6396 		}
6397 	}
6398 }
6399 
6400 /* Do accounting for the sndbuf space.
6401  * Decrement the used sndbuf space of the corresponding association by the
6402  * data size which was just transmitted(freed).
6403  */
6404 static void sctp_wfree(struct sk_buff *skb)
6405 {
6406 	struct sctp_association *asoc;
6407 	struct sctp_chunk *chunk;
6408 	struct sock *sk;
6409 
6410 	/* Get the saved chunk pointer.  */
6411 	chunk = *((struct sctp_chunk **)(skb->cb));
6412 	asoc = chunk->asoc;
6413 	sk = asoc->base.sk;
6414 	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
6415 				sizeof(struct sk_buff) +
6416 				sizeof(struct sctp_chunk);
6417 
6418 	atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
6419 
6420 	/*
6421 	 * This undoes what is done via sctp_set_owner_w and sk_mem_charge
6422 	 */
6423 	sk->sk_wmem_queued   -= skb->truesize;
6424 	sk_mem_uncharge(sk, skb->truesize);
6425 
6426 	sock_wfree(skb);
6427 	__sctp_write_space(asoc);
6428 
6429 	sctp_association_put(asoc);
6430 }
6431 
6432 /* Do accounting for the receive space on the socket.
6433  * Accounting for the association is done in ulpevent.c
6434  * We set this as a destructor for the cloned data skbs so that
6435  * accounting is done at the correct time.
6436  */
6437 void sctp_sock_rfree(struct sk_buff *skb)
6438 {
6439 	struct sock *sk = skb->sk;
6440 	struct sctp_ulpevent *event = sctp_skb2event(skb);
6441 
6442 	atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
6443 
6444 	/*
6445 	 * Mimic the behavior of sock_rfree
6446 	 */
6447 	sk_mem_uncharge(sk, event->rmem_len);
6448 }
6449 
6450 
6451 /* Helper function to wait for space in the sndbuf.  */
6452 static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
6453 				size_t msg_len)
6454 {
6455 	struct sock *sk = asoc->base.sk;
6456 	int err = 0;
6457 	long current_timeo = *timeo_p;
6458 	DEFINE_WAIT(wait);
6459 
6460 	SCTP_DEBUG_PRINTK("wait_for_sndbuf: asoc=%p, timeo=%ld, msg_len=%zu\n",
6461 			  asoc, (long)(*timeo_p), msg_len);
6462 
6463 	/* Increment the association's refcnt.  */
6464 	sctp_association_hold(asoc);
6465 
6466 	/* Wait on the association specific sndbuf space. */
6467 	for (;;) {
6468 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6469 					  TASK_INTERRUPTIBLE);
6470 		if (!*timeo_p)
6471 			goto do_nonblock;
6472 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6473 		    asoc->base.dead)
6474 			goto do_error;
6475 		if (signal_pending(current))
6476 			goto do_interrupted;
6477 		if (msg_len <= sctp_wspace(asoc))
6478 			break;
6479 
6480 		/* Let another process have a go.  Since we are going
6481 		 * to sleep anyway.
6482 		 */
6483 		sctp_release_sock(sk);
6484 		current_timeo = schedule_timeout(current_timeo);
6485 		BUG_ON(sk != asoc->base.sk);
6486 		sctp_lock_sock(sk);
6487 
6488 		*timeo_p = current_timeo;
6489 	}
6490 
6491 out:
6492 	finish_wait(&asoc->wait, &wait);
6493 
6494 	/* Release the association's refcnt.  */
6495 	sctp_association_put(asoc);
6496 
6497 	return err;
6498 
6499 do_error:
6500 	err = -EPIPE;
6501 	goto out;
6502 
6503 do_interrupted:
6504 	err = sock_intr_errno(*timeo_p);
6505 	goto out;
6506 
6507 do_nonblock:
6508 	err = -EAGAIN;
6509 	goto out;
6510 }
6511 
6512 /* If socket sndbuf has changed, wake up all per association waiters.  */
6513 void sctp_write_space(struct sock *sk)
6514 {
6515 	struct sctp_association *asoc;
6516 
6517 	/* Wake up the tasks in each wait queue.  */
6518 	list_for_each_entry(asoc, &((sctp_sk(sk))->ep->asocs), asocs) {
6519 		__sctp_write_space(asoc);
6520 	}
6521 }
6522 
6523 /* Is there any sndbuf space available on the socket?
6524  *
6525  * Note that sk_wmem_alloc is the sum of the send buffers on all of the
6526  * associations on the same socket.  For a UDP-style socket with
6527  * multiple associations, it is possible for it to be "unwriteable"
6528  * prematurely.  I assume that this is acceptable because
6529  * a premature "unwriteable" is better than an accidental "writeable" which
6530  * would cause an unwanted block under certain circumstances.  For the 1-1
6531  * UDP-style sockets or TCP-style sockets, this code should work.
6532  *  - Daisy
6533  */
6534 static int sctp_writeable(struct sock *sk)
6535 {
6536 	int amt = 0;
6537 
6538 	amt = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
6539 	if (amt < 0)
6540 		amt = 0;
6541 	return amt;
6542 }
6543 
6544 /* Wait for an association to go into ESTABLISHED state. If timeout is 0,
6545  * returns immediately with EINPROGRESS.
6546  */
6547 static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
6548 {
6549 	struct sock *sk = asoc->base.sk;
6550 	int err = 0;
6551 	long current_timeo = *timeo_p;
6552 	DEFINE_WAIT(wait);
6553 
6554 	SCTP_DEBUG_PRINTK("%s: asoc=%p, timeo=%ld\n", __func__, asoc,
6555 			  (long)(*timeo_p));
6556 
6557 	/* Increment the association's refcnt.  */
6558 	sctp_association_hold(asoc);
6559 
6560 	for (;;) {
6561 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6562 					  TASK_INTERRUPTIBLE);
6563 		if (!*timeo_p)
6564 			goto do_nonblock;
6565 		if (sk->sk_shutdown & RCV_SHUTDOWN)
6566 			break;
6567 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6568 		    asoc->base.dead)
6569 			goto do_error;
6570 		if (signal_pending(current))
6571 			goto do_interrupted;
6572 
6573 		if (sctp_state(asoc, ESTABLISHED))
6574 			break;
6575 
6576 		/* Let another process have a go.  Since we are going
6577 		 * to sleep anyway.
6578 		 */
6579 		sctp_release_sock(sk);
6580 		current_timeo = schedule_timeout(current_timeo);
6581 		sctp_lock_sock(sk);
6582 
6583 		*timeo_p = current_timeo;
6584 	}
6585 
6586 out:
6587 	finish_wait(&asoc->wait, &wait);
6588 
6589 	/* Release the association's refcnt.  */
6590 	sctp_association_put(asoc);
6591 
6592 	return err;
6593 
6594 do_error:
6595 	if (asoc->init_err_counter + 1 > asoc->max_init_attempts)
6596 		err = -ETIMEDOUT;
6597 	else
6598 		err = -ECONNREFUSED;
6599 	goto out;
6600 
6601 do_interrupted:
6602 	err = sock_intr_errno(*timeo_p);
6603 	goto out;
6604 
6605 do_nonblock:
6606 	err = -EINPROGRESS;
6607 	goto out;
6608 }
6609 
6610 static int sctp_wait_for_accept(struct sock *sk, long timeo)
6611 {
6612 	struct sctp_endpoint *ep;
6613 	int err = 0;
6614 	DEFINE_WAIT(wait);
6615 
6616 	ep = sctp_sk(sk)->ep;
6617 
6618 
6619 	for (;;) {
6620 		prepare_to_wait_exclusive(sk->sk_sleep, &wait,
6621 					  TASK_INTERRUPTIBLE);
6622 
6623 		if (list_empty(&ep->asocs)) {
6624 			sctp_release_sock(sk);
6625 			timeo = schedule_timeout(timeo);
6626 			sctp_lock_sock(sk);
6627 		}
6628 
6629 		err = -EINVAL;
6630 		if (!sctp_sstate(sk, LISTENING))
6631 			break;
6632 
6633 		err = 0;
6634 		if (!list_empty(&ep->asocs))
6635 			break;
6636 
6637 		err = sock_intr_errno(timeo);
6638 		if (signal_pending(current))
6639 			break;
6640 
6641 		err = -EAGAIN;
6642 		if (!timeo)
6643 			break;
6644 	}
6645 
6646 	finish_wait(sk->sk_sleep, &wait);
6647 
6648 	return err;
6649 }
6650 
6651 static void sctp_wait_for_close(struct sock *sk, long timeout)
6652 {
6653 	DEFINE_WAIT(wait);
6654 
6655 	do {
6656 		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
6657 		if (list_empty(&sctp_sk(sk)->ep->asocs))
6658 			break;
6659 		sctp_release_sock(sk);
6660 		timeout = schedule_timeout(timeout);
6661 		sctp_lock_sock(sk);
6662 	} while (!signal_pending(current) && timeout);
6663 
6664 	finish_wait(sk->sk_sleep, &wait);
6665 }
6666 
6667 static void sctp_skb_set_owner_r_frag(struct sk_buff *skb, struct sock *sk)
6668 {
6669 	struct sk_buff *frag;
6670 
6671 	if (!skb->data_len)
6672 		goto done;
6673 
6674 	/* Don't forget the fragments. */
6675 	skb_walk_frags(skb, frag)
6676 		sctp_skb_set_owner_r_frag(frag, sk);
6677 
6678 done:
6679 	sctp_skb_set_owner_r(skb, sk);
6680 }
6681 
6682 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
6683 		    struct sctp_association *asoc)
6684 {
6685 	struct inet_sock *inet = inet_sk(sk);
6686 	struct inet_sock *newinet = inet_sk(newsk);
6687 
6688 	newsk->sk_type = sk->sk_type;
6689 	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
6690 	newsk->sk_flags = sk->sk_flags;
6691 	newsk->sk_no_check = sk->sk_no_check;
6692 	newsk->sk_reuse = sk->sk_reuse;
6693 
6694 	newsk->sk_shutdown = sk->sk_shutdown;
6695 	newsk->sk_destruct = inet_sock_destruct;
6696 	newsk->sk_family = sk->sk_family;
6697 	newsk->sk_protocol = IPPROTO_SCTP;
6698 	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
6699 	newsk->sk_sndbuf = sk->sk_sndbuf;
6700 	newsk->sk_rcvbuf = sk->sk_rcvbuf;
6701 	newsk->sk_lingertime = sk->sk_lingertime;
6702 	newsk->sk_rcvtimeo = sk->sk_rcvtimeo;
6703 	newsk->sk_sndtimeo = sk->sk_sndtimeo;
6704 
6705 	newinet = inet_sk(newsk);
6706 
6707 	/* Initialize sk's sport, dport, rcv_saddr and daddr for
6708 	 * getsockname() and getpeername()
6709 	 */
6710 	newinet->sport = inet->sport;
6711 	newinet->saddr = inet->saddr;
6712 	newinet->rcv_saddr = inet->rcv_saddr;
6713 	newinet->dport = htons(asoc->peer.port);
6714 	newinet->pmtudisc = inet->pmtudisc;
6715 	newinet->id = asoc->next_tsn ^ jiffies;
6716 
6717 	newinet->uc_ttl = inet->uc_ttl;
6718 	newinet->mc_loop = 1;
6719 	newinet->mc_ttl = 1;
6720 	newinet->mc_index = 0;
6721 	newinet->mc_list = NULL;
6722 }
6723 
6724 /* Populate the fields of the newsk from the oldsk and migrate the assoc
6725  * and its messages to the newsk.
6726  */
6727 static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
6728 			      struct sctp_association *assoc,
6729 			      sctp_socket_type_t type)
6730 {
6731 	struct sctp_sock *oldsp = sctp_sk(oldsk);
6732 	struct sctp_sock *newsp = sctp_sk(newsk);
6733 	struct sctp_bind_bucket *pp; /* hash list port iterator */
6734 	struct sctp_endpoint *newep = newsp->ep;
6735 	struct sk_buff *skb, *tmp;
6736 	struct sctp_ulpevent *event;
6737 	struct sctp_bind_hashbucket *head;
6738 
6739 	/* Migrate socket buffer sizes and all the socket level options to the
6740 	 * new socket.
6741 	 */
6742 	newsk->sk_sndbuf = oldsk->sk_sndbuf;
6743 	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
6744 	/* Brute force copy old sctp opt. */
6745 	inet_sk_copy_descendant(newsk, oldsk);
6746 
6747 	/* Restore the ep value that was overwritten with the above structure
6748 	 * copy.
6749 	 */
6750 	newsp->ep = newep;
6751 	newsp->hmac = NULL;
6752 
6753 	/* Hook this new socket in to the bind_hash list. */
6754 	head = &sctp_port_hashtable[sctp_phashfn(inet_sk(oldsk)->num)];
6755 	sctp_local_bh_disable();
6756 	sctp_spin_lock(&head->lock);
6757 	pp = sctp_sk(oldsk)->bind_hash;
6758 	sk_add_bind_node(newsk, &pp->owner);
6759 	sctp_sk(newsk)->bind_hash = pp;
6760 	inet_sk(newsk)->num = inet_sk(oldsk)->num;
6761 	sctp_spin_unlock(&head->lock);
6762 	sctp_local_bh_enable();
6763 
6764 	/* Copy the bind_addr list from the original endpoint to the new
6765 	 * endpoint so that we can handle restarts properly
6766 	 */
6767 	sctp_bind_addr_dup(&newsp->ep->base.bind_addr,
6768 				&oldsp->ep->base.bind_addr, GFP_KERNEL);
6769 
6770 	/* Move any messages in the old socket's receive queue that are for the
6771 	 * peeled off association to the new socket's receive queue.
6772 	 */
6773 	sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
6774 		event = sctp_skb2event(skb);
6775 		if (event->asoc == assoc) {
6776 			__skb_unlink(skb, &oldsk->sk_receive_queue);
6777 			__skb_queue_tail(&newsk->sk_receive_queue, skb);
6778 			sctp_skb_set_owner_r_frag(skb, newsk);
6779 		}
6780 	}
6781 
6782 	/* Clean up any messages pending delivery due to partial
6783 	 * delivery.   Three cases:
6784 	 * 1) No partial deliver;  no work.
6785 	 * 2) Peeling off partial delivery; keep pd_lobby in new pd_lobby.
6786 	 * 3) Peeling off non-partial delivery; move pd_lobby to receive_queue.
6787 	 */
6788 	skb_queue_head_init(&newsp->pd_lobby);
6789 	atomic_set(&sctp_sk(newsk)->pd_mode, assoc->ulpq.pd_mode);
6790 
6791 	if (atomic_read(&sctp_sk(oldsk)->pd_mode)) {
6792 		struct sk_buff_head *queue;
6793 
6794 		/* Decide which queue to move pd_lobby skbs to. */
6795 		if (assoc->ulpq.pd_mode) {
6796 			queue = &newsp->pd_lobby;
6797 		} else
6798 			queue = &newsk->sk_receive_queue;
6799 
6800 		/* Walk through the pd_lobby, looking for skbs that
6801 		 * need moved to the new socket.
6802 		 */
6803 		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
6804 			event = sctp_skb2event(skb);
6805 			if (event->asoc == assoc) {
6806 				__skb_unlink(skb, &oldsp->pd_lobby);
6807 				__skb_queue_tail(queue, skb);
6808 				sctp_skb_set_owner_r_frag(skb, newsk);
6809 			}
6810 		}
6811 
6812 		/* Clear up any skbs waiting for the partial
6813 		 * delivery to finish.
6814 		 */
6815 		if (assoc->ulpq.pd_mode)
6816 			sctp_clear_pd(oldsk, NULL);
6817 
6818 	}
6819 
6820 	sctp_skb_for_each(skb, &assoc->ulpq.reasm, tmp)
6821 		sctp_skb_set_owner_r_frag(skb, newsk);
6822 
6823 	sctp_skb_for_each(skb, &assoc->ulpq.lobby, tmp)
6824 		sctp_skb_set_owner_r_frag(skb, newsk);
6825 
6826 	/* Set the type of socket to indicate that it is peeled off from the
6827 	 * original UDP-style socket or created with the accept() call on a
6828 	 * TCP-style socket..
6829 	 */
6830 	newsp->type = type;
6831 
6832 	/* Mark the new socket "in-use" by the user so that any packets
6833 	 * that may arrive on the association after we've moved it are
6834 	 * queued to the backlog.  This prevents a potential race between
6835 	 * backlog processing on the old socket and new-packet processing
6836 	 * on the new socket.
6837 	 *
6838 	 * The caller has just allocated newsk so we can guarantee that other
6839 	 * paths won't try to lock it and then oldsk.
6840 	 */
6841 	lock_sock_nested(newsk, SINGLE_DEPTH_NESTING);
6842 	sctp_assoc_migrate(assoc, newsk);
6843 
6844 	/* If the association on the newsk is already closed before accept()
6845 	 * is called, set RCV_SHUTDOWN flag.
6846 	 */
6847 	if (sctp_state(assoc, CLOSED) && sctp_style(newsk, TCP))
6848 		newsk->sk_shutdown |= RCV_SHUTDOWN;
6849 
6850 	newsk->sk_state = SCTP_SS_ESTABLISHED;
6851 	sctp_release_sock(newsk);
6852 }
6853 
6854 
6855 /* This proto struct describes the ULP interface for SCTP.  */
6856 struct proto sctp_prot = {
6857 	.name        =	"SCTP",
6858 	.owner       =	THIS_MODULE,
6859 	.close       =	sctp_close,
6860 	.connect     =	sctp_connect,
6861 	.disconnect  =	sctp_disconnect,
6862 	.accept      =	sctp_accept,
6863 	.ioctl       =	sctp_ioctl,
6864 	.init        =	sctp_init_sock,
6865 	.destroy     =	sctp_destroy_sock,
6866 	.shutdown    =	sctp_shutdown,
6867 	.setsockopt  =	sctp_setsockopt,
6868 	.getsockopt  =	sctp_getsockopt,
6869 	.sendmsg     =	sctp_sendmsg,
6870 	.recvmsg     =	sctp_recvmsg,
6871 	.bind        =	sctp_bind,
6872 	.backlog_rcv =	sctp_backlog_rcv,
6873 	.hash        =	sctp_hash,
6874 	.unhash      =	sctp_unhash,
6875 	.get_port    =	sctp_get_port,
6876 	.obj_size    =  sizeof(struct sctp_sock),
6877 	.sysctl_mem  =  sysctl_sctp_mem,
6878 	.sysctl_rmem =  sysctl_sctp_rmem,
6879 	.sysctl_wmem =  sysctl_sctp_wmem,
6880 	.memory_pressure = &sctp_memory_pressure,
6881 	.enter_memory_pressure = sctp_enter_memory_pressure,
6882 	.memory_allocated = &sctp_memory_allocated,
6883 	.sockets_allocated = &sctp_sockets_allocated,
6884 };
6885 
6886 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6887 
6888 struct proto sctpv6_prot = {
6889 	.name		= "SCTPv6",
6890 	.owner		= THIS_MODULE,
6891 	.close		= sctp_close,
6892 	.connect	= sctp_connect,
6893 	.disconnect	= sctp_disconnect,
6894 	.accept		= sctp_accept,
6895 	.ioctl		= sctp_ioctl,
6896 	.init		= sctp_init_sock,
6897 	.destroy	= sctp_destroy_sock,
6898 	.shutdown	= sctp_shutdown,
6899 	.setsockopt	= sctp_setsockopt,
6900 	.getsockopt	= sctp_getsockopt,
6901 	.sendmsg	= sctp_sendmsg,
6902 	.recvmsg	= sctp_recvmsg,
6903 	.bind		= sctp_bind,
6904 	.backlog_rcv	= sctp_backlog_rcv,
6905 	.hash		= sctp_hash,
6906 	.unhash		= sctp_unhash,
6907 	.get_port	= sctp_get_port,
6908 	.obj_size	= sizeof(struct sctp6_sock),
6909 	.sysctl_mem	= sysctl_sctp_mem,
6910 	.sysctl_rmem	= sysctl_sctp_rmem,
6911 	.sysctl_wmem	= sysctl_sctp_wmem,
6912 	.memory_pressure = &sctp_memory_pressure,
6913 	.enter_memory_pressure = sctp_enter_memory_pressure,
6914 	.memory_allocated = &sctp_memory_allocated,
6915 	.sockets_allocated = &sctp_sockets_allocated,
6916 };
6917 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
6918