xref: /linux/net/sctp/socket.c (revision bd49666974a12f39eb9c74044e0b1753efcd94c4)
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 static atomic_t sctp_sockets_allocated;
118 
119 static void sctp_enter_memory_pressure(void)
120 {
121 	sctp_memory_pressure = 1;
122 }
123 
124 
125 /* Get the sndbuf space available at the time on the association.  */
126 static inline int sctp_wspace(struct sctp_association *asoc)
127 {
128 	int amt;
129 
130 	if (asoc->ep->sndbuf_policy)
131 		amt = asoc->sndbuf_used;
132 	else
133 		amt = atomic_read(&asoc->base.sk->sk_wmem_alloc);
134 
135 	if (amt >= asoc->base.sk->sk_sndbuf) {
136 		if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK)
137 			amt = 0;
138 		else {
139 			amt = sk_stream_wspace(asoc->base.sk);
140 			if (amt < 0)
141 				amt = 0;
142 		}
143 	} else {
144 		amt = asoc->base.sk->sk_sndbuf - amt;
145 	}
146 	return amt;
147 }
148 
149 /* Increment the used sndbuf space count of the corresponding association by
150  * the size of the outgoing data chunk.
151  * Also, set the skb destructor for sndbuf accounting later.
152  *
153  * Since it is always 1-1 between chunk and skb, and also a new skb is always
154  * allocated for chunk bundling in sctp_packet_transmit(), we can use the
155  * destructor in the data chunk skb for the purpose of the sndbuf space
156  * tracking.
157  */
158 static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
159 {
160 	struct sctp_association *asoc = chunk->asoc;
161 	struct sock *sk = asoc->base.sk;
162 
163 	/* The sndbuf space is tracked per association.  */
164 	sctp_association_hold(asoc);
165 
166 	skb_set_owner_w(chunk->skb, sk);
167 
168 	chunk->skb->destructor = sctp_wfree;
169 	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
170 	*((struct sctp_chunk **)(chunk->skb->cb)) = chunk;
171 
172 	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
173 				sizeof(struct sk_buff) +
174 				sizeof(struct sctp_chunk);
175 
176 	atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
177 	sk->sk_wmem_queued += chunk->skb->truesize;
178 	sk_mem_charge(sk, chunk->skb->truesize);
179 }
180 
181 /* Verify that this is a valid address. */
182 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
183 				   int len)
184 {
185 	struct sctp_af *af;
186 
187 	/* Verify basic sockaddr. */
188 	af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
189 	if (!af)
190 		return -EINVAL;
191 
192 	/* Is this a valid SCTP address?  */
193 	if (!af->addr_valid(addr, sctp_sk(sk), NULL))
194 		return -EINVAL;
195 
196 	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
197 		return -EINVAL;
198 
199 	return 0;
200 }
201 
202 /* Look up the association by its id.  If this is not a UDP-style
203  * socket, the ID field is always ignored.
204  */
205 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
206 {
207 	struct sctp_association *asoc = NULL;
208 
209 	/* If this is not a UDP-style socket, assoc id should be ignored. */
210 	if (!sctp_style(sk, UDP)) {
211 		/* Return NULL if the socket state is not ESTABLISHED. It
212 		 * could be a TCP-style listening socket or a socket which
213 		 * hasn't yet called connect() to establish an association.
214 		 */
215 		if (!sctp_sstate(sk, ESTABLISHED))
216 			return NULL;
217 
218 		/* Get the first and the only association from the list. */
219 		if (!list_empty(&sctp_sk(sk)->ep->asocs))
220 			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
221 					  struct sctp_association, asocs);
222 		return asoc;
223 	}
224 
225 	/* Otherwise this is a UDP-style socket. */
226 	if (!id || (id == (sctp_assoc_t)-1))
227 		return NULL;
228 
229 	spin_lock_bh(&sctp_assocs_id_lock);
230 	asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
231 	spin_unlock_bh(&sctp_assocs_id_lock);
232 
233 	if (!asoc || (asoc->base.sk != sk) || asoc->base.dead)
234 		return NULL;
235 
236 	return asoc;
237 }
238 
239 /* Look up the transport from an address and an assoc id. If both address and
240  * id are specified, the associations matching the address and the id should be
241  * the same.
242  */
243 static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
244 					      struct sockaddr_storage *addr,
245 					      sctp_assoc_t id)
246 {
247 	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
248 	struct sctp_transport *transport;
249 	union sctp_addr *laddr = (union sctp_addr *)addr;
250 
251 	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
252 					       laddr,
253 					       &transport);
254 
255 	if (!addr_asoc)
256 		return NULL;
257 
258 	id_asoc = sctp_id2assoc(sk, id);
259 	if (id_asoc && (id_asoc != addr_asoc))
260 		return NULL;
261 
262 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
263 						(union sctp_addr *)addr);
264 
265 	return transport;
266 }
267 
268 /* API 3.1.2 bind() - UDP Style Syntax
269  * The syntax of bind() is,
270  *
271  *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
272  *
273  *   sd      - the socket descriptor returned by socket().
274  *   addr    - the address structure (struct sockaddr_in or struct
275  *             sockaddr_in6 [RFC 2553]),
276  *   addr_len - the size of the address structure.
277  */
278 SCTP_STATIC int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
279 {
280 	int retval = 0;
281 
282 	sctp_lock_sock(sk);
283 
284 	SCTP_DEBUG_PRINTK("sctp_bind(sk: %p, addr: %p, addr_len: %d)\n",
285 			  sk, addr, addr_len);
286 
287 	/* Disallow binding twice. */
288 	if (!sctp_sk(sk)->ep->base.bind_addr.port)
289 		retval = sctp_do_bind(sk, (union sctp_addr *)addr,
290 				      addr_len);
291 	else
292 		retval = -EINVAL;
293 
294 	sctp_release_sock(sk);
295 
296 	return retval;
297 }
298 
299 static long sctp_get_port_local(struct sock *, union sctp_addr *);
300 
301 /* Verify this is a valid sockaddr. */
302 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
303 					union sctp_addr *addr, int len)
304 {
305 	struct sctp_af *af;
306 
307 	/* Check minimum size.  */
308 	if (len < sizeof (struct sockaddr))
309 		return NULL;
310 
311 	/* Does this PF support this AF? */
312 	if (!opt->pf->af_supported(addr->sa.sa_family, opt))
313 		return NULL;
314 
315 	/* If we get this far, af is valid. */
316 	af = sctp_get_af_specific(addr->sa.sa_family);
317 
318 	if (len < af->sockaddr_len)
319 		return NULL;
320 
321 	return af;
322 }
323 
324 /* Bind a local address either to an endpoint or to an association.  */
325 SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
326 {
327 	struct sctp_sock *sp = sctp_sk(sk);
328 	struct sctp_endpoint *ep = sp->ep;
329 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
330 	struct sctp_af *af;
331 	unsigned short snum;
332 	int ret = 0;
333 
334 	/* Common sockaddr verification. */
335 	af = sctp_sockaddr_af(sp, addr, len);
336 	if (!af) {
337 		SCTP_DEBUG_PRINTK("sctp_do_bind(sk: %p, newaddr: %p, len: %d) EINVAL\n",
338 				  sk, addr, len);
339 		return -EINVAL;
340 	}
341 
342 	snum = ntohs(addr->v4.sin_port);
343 
344 	SCTP_DEBUG_PRINTK_IPADDR("sctp_do_bind(sk: %p, new addr: ",
345 				 ", port: %d, new port: %d, len: %d)\n",
346 				 sk,
347 				 addr,
348 				 bp->port, snum,
349 				 len);
350 
351 	/* PF specific bind() address verification. */
352 	if (!sp->pf->bind_verify(sp, addr))
353 		return -EADDRNOTAVAIL;
354 
355 	/* We must either be unbound, or bind to the same port.
356 	 * It's OK to allow 0 ports if we are already bound.
357 	 * We'll just inhert an already bound port in this case
358 	 */
359 	if (bp->port) {
360 		if (!snum)
361 			snum = bp->port;
362 		else if (snum != bp->port) {
363 			SCTP_DEBUG_PRINTK("sctp_do_bind:"
364 				  " New port %d does not match existing port "
365 				  "%d.\n", snum, bp->port);
366 			return -EINVAL;
367 		}
368 	}
369 
370 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
371 		return -EACCES;
372 
373 	/* Make sure we are allowed to bind here.
374 	 * The function sctp_get_port_local() does duplicate address
375 	 * detection.
376 	 */
377 	addr->v4.sin_port = htons(snum);
378 	if ((ret = sctp_get_port_local(sk, addr))) {
379 		if (ret == (long) sk) {
380 			/* This endpoint has a conflicting address. */
381 			return -EINVAL;
382 		} else {
383 			return -EADDRINUSE;
384 		}
385 	}
386 
387 	/* Refresh ephemeral port.  */
388 	if (!bp->port)
389 		bp->port = inet_sk(sk)->num;
390 
391 	/* Add the address to the bind address list.
392 	 * Use GFP_ATOMIC since BHs will be disabled.
393 	 */
394 	ret = sctp_add_bind_addr(bp, addr, SCTP_ADDR_SRC, GFP_ATOMIC);
395 
396 	/* Copy back into socket for getsockname() use. */
397 	if (!ret) {
398 		inet_sk(sk)->sport = htons(inet_sk(sk)->num);
399 		af->to_sk_saddr(addr, sk);
400 	}
401 
402 	return ret;
403 }
404 
405  /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
406  *
407  * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
408  * at any one time.  If a sender, after sending an ASCONF chunk, decides
409  * it needs to transfer another ASCONF Chunk, it MUST wait until the
410  * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
411  * subsequent ASCONF. Note this restriction binds each side, so at any
412  * time two ASCONF may be in-transit on any given association (one sent
413  * from each endpoint).
414  */
415 static int sctp_send_asconf(struct sctp_association *asoc,
416 			    struct sctp_chunk *chunk)
417 {
418 	int		retval = 0;
419 
420 	/* If there is an outstanding ASCONF chunk, queue it for later
421 	 * transmission.
422 	 */
423 	if (asoc->addip_last_asconf) {
424 		list_add_tail(&chunk->list, &asoc->addip_chunk_list);
425 		goto out;
426 	}
427 
428 	/* Hold the chunk until an ASCONF_ACK is received. */
429 	sctp_chunk_hold(chunk);
430 	retval = sctp_primitive_ASCONF(asoc, chunk);
431 	if (retval)
432 		sctp_chunk_free(chunk);
433 	else
434 		asoc->addip_last_asconf = chunk;
435 
436 out:
437 	return retval;
438 }
439 
440 /* Add a list of addresses as bind addresses to local endpoint or
441  * association.
442  *
443  * Basically run through each address specified in the addrs/addrcnt
444  * array/length pair, determine if it is IPv6 or IPv4 and call
445  * sctp_do_bind() on it.
446  *
447  * If any of them fails, then the operation will be reversed and the
448  * ones that were added will be removed.
449  *
450  * Only sctp_setsockopt_bindx() is supposed to call this function.
451  */
452 static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
453 {
454 	int cnt;
455 	int retval = 0;
456 	void *addr_buf;
457 	struct sockaddr *sa_addr;
458 	struct sctp_af *af;
459 
460 	SCTP_DEBUG_PRINTK("sctp_bindx_add (sk: %p, addrs: %p, addrcnt: %d)\n",
461 			  sk, addrs, addrcnt);
462 
463 	addr_buf = addrs;
464 	for (cnt = 0; cnt < addrcnt; cnt++) {
465 		/* The list may contain either IPv4 or IPv6 address;
466 		 * determine the address length for walking thru the list.
467 		 */
468 		sa_addr = (struct sockaddr *)addr_buf;
469 		af = sctp_get_af_specific(sa_addr->sa_family);
470 		if (!af) {
471 			retval = -EINVAL;
472 			goto err_bindx_add;
473 		}
474 
475 		retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
476 				      af->sockaddr_len);
477 
478 		addr_buf += af->sockaddr_len;
479 
480 err_bindx_add:
481 		if (retval < 0) {
482 			/* Failed. Cleanup the ones that have been added */
483 			if (cnt > 0)
484 				sctp_bindx_rem(sk, addrs, cnt);
485 			return retval;
486 		}
487 	}
488 
489 	return retval;
490 }
491 
492 /* Send an ASCONF chunk with Add IP address parameters to all the peers of the
493  * associations that are part of the endpoint indicating that a list of local
494  * addresses are added to the endpoint.
495  *
496  * If any of the addresses is already in the bind address list of the
497  * association, we do not send the chunk for that association.  But it will not
498  * affect other associations.
499  *
500  * Only sctp_setsockopt_bindx() is supposed to call this function.
501  */
502 static int sctp_send_asconf_add_ip(struct sock		*sk,
503 				   struct sockaddr	*addrs,
504 				   int 			addrcnt)
505 {
506 	struct sctp_sock		*sp;
507 	struct sctp_endpoint		*ep;
508 	struct sctp_association		*asoc;
509 	struct sctp_bind_addr		*bp;
510 	struct sctp_chunk		*chunk;
511 	struct sctp_sockaddr_entry	*laddr;
512 	union sctp_addr			*addr;
513 	union sctp_addr			saveaddr;
514 	void				*addr_buf;
515 	struct sctp_af			*af;
516 	struct list_head		*pos;
517 	struct list_head		*p;
518 	int 				i;
519 	int 				retval = 0;
520 
521 	if (!sctp_addip_enable)
522 		return retval;
523 
524 	sp = sctp_sk(sk);
525 	ep = sp->ep;
526 
527 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
528 			  __FUNCTION__, sk, addrs, addrcnt);
529 
530 	list_for_each(pos, &ep->asocs) {
531 		asoc = list_entry(pos, struct sctp_association, asocs);
532 
533 		if (!asoc->peer.asconf_capable)
534 			continue;
535 
536 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
537 			continue;
538 
539 		if (!sctp_state(asoc, ESTABLISHED))
540 			continue;
541 
542 		/* Check if any address in the packed array of addresses is
543 		 * in the bind address list of the association. If so,
544 		 * do not send the asconf chunk to its peer, but continue with
545 		 * other associations.
546 		 */
547 		addr_buf = addrs;
548 		for (i = 0; i < addrcnt; i++) {
549 			addr = (union sctp_addr *)addr_buf;
550 			af = sctp_get_af_specific(addr->v4.sin_family);
551 			if (!af) {
552 				retval = -EINVAL;
553 				goto out;
554 			}
555 
556 			if (sctp_assoc_lookup_laddr(asoc, addr))
557 				break;
558 
559 			addr_buf += af->sockaddr_len;
560 		}
561 		if (i < addrcnt)
562 			continue;
563 
564 		/* Use the first valid address in bind addr list of
565 		 * association as Address Parameter of ASCONF CHUNK.
566 		 */
567 		bp = &asoc->base.bind_addr;
568 		p = bp->address_list.next;
569 		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
570 		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
571 						   addrcnt, SCTP_PARAM_ADD_IP);
572 		if (!chunk) {
573 			retval = -ENOMEM;
574 			goto out;
575 		}
576 
577 		retval = sctp_send_asconf(asoc, chunk);
578 		if (retval)
579 			goto out;
580 
581 		/* Add the new addresses to the bind address list with
582 		 * use_as_src set to 0.
583 		 */
584 		addr_buf = addrs;
585 		for (i = 0; i < addrcnt; i++) {
586 			addr = (union sctp_addr *)addr_buf;
587 			af = sctp_get_af_specific(addr->v4.sin_family);
588 			memcpy(&saveaddr, addr, af->sockaddr_len);
589 			retval = sctp_add_bind_addr(bp, &saveaddr,
590 						    SCTP_ADDR_NEW, GFP_ATOMIC);
591 			addr_buf += af->sockaddr_len;
592 		}
593 	}
594 
595 out:
596 	return retval;
597 }
598 
599 /* Remove a list of addresses from bind addresses list.  Do not remove the
600  * last address.
601  *
602  * Basically run through each address specified in the addrs/addrcnt
603  * array/length pair, determine if it is IPv6 or IPv4 and call
604  * sctp_del_bind() on it.
605  *
606  * If any of them fails, then the operation will be reversed and the
607  * ones that were removed will be added back.
608  *
609  * At least one address has to be left; if only one address is
610  * available, the operation will return -EBUSY.
611  *
612  * Only sctp_setsockopt_bindx() is supposed to call this function.
613  */
614 static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
615 {
616 	struct sctp_sock *sp = sctp_sk(sk);
617 	struct sctp_endpoint *ep = sp->ep;
618 	int cnt;
619 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
620 	int retval = 0;
621 	void *addr_buf;
622 	union sctp_addr *sa_addr;
623 	struct sctp_af *af;
624 
625 	SCTP_DEBUG_PRINTK("sctp_bindx_rem (sk: %p, addrs: %p, addrcnt: %d)\n",
626 			  sk, addrs, addrcnt);
627 
628 	addr_buf = addrs;
629 	for (cnt = 0; cnt < addrcnt; cnt++) {
630 		/* If the bind address list is empty or if there is only one
631 		 * bind address, there is nothing more to be removed (we need
632 		 * at least one address here).
633 		 */
634 		if (list_empty(&bp->address_list) ||
635 		    (sctp_list_single_entry(&bp->address_list))) {
636 			retval = -EBUSY;
637 			goto err_bindx_rem;
638 		}
639 
640 		sa_addr = (union sctp_addr *)addr_buf;
641 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
642 		if (!af) {
643 			retval = -EINVAL;
644 			goto err_bindx_rem;
645 		}
646 
647 		if (!af->addr_valid(sa_addr, sp, NULL)) {
648 			retval = -EADDRNOTAVAIL;
649 			goto err_bindx_rem;
650 		}
651 
652 		if (sa_addr->v4.sin_port != htons(bp->port)) {
653 			retval = -EINVAL;
654 			goto err_bindx_rem;
655 		}
656 
657 		/* FIXME - There is probably a need to check if sk->sk_saddr and
658 		 * sk->sk_rcv_addr are currently set to one of the addresses to
659 		 * be removed. This is something which needs to be looked into
660 		 * when we are fixing the outstanding issues with multi-homing
661 		 * socket routing and failover schemes. Refer to comments in
662 		 * sctp_do_bind(). -daisy
663 		 */
664 		retval = sctp_del_bind_addr(bp, sa_addr);
665 
666 		addr_buf += af->sockaddr_len;
667 err_bindx_rem:
668 		if (retval < 0) {
669 			/* Failed. Add the ones that has been removed back */
670 			if (cnt > 0)
671 				sctp_bindx_add(sk, addrs, cnt);
672 			return retval;
673 		}
674 	}
675 
676 	return retval;
677 }
678 
679 /* Send an ASCONF chunk with Delete IP address parameters to all the peers of
680  * the associations that are part of the endpoint indicating that a list of
681  * local addresses are removed from the endpoint.
682  *
683  * If any of the addresses is already in the bind address list of the
684  * association, we do not send the chunk for that association.  But it will not
685  * affect other associations.
686  *
687  * Only sctp_setsockopt_bindx() is supposed to call this function.
688  */
689 static int sctp_send_asconf_del_ip(struct sock		*sk,
690 				   struct sockaddr	*addrs,
691 				   int			addrcnt)
692 {
693 	struct sctp_sock	*sp;
694 	struct sctp_endpoint	*ep;
695 	struct sctp_association	*asoc;
696 	struct sctp_transport	*transport;
697 	struct sctp_bind_addr	*bp;
698 	struct sctp_chunk	*chunk;
699 	union sctp_addr		*laddr;
700 	void			*addr_buf;
701 	struct sctp_af		*af;
702 	struct list_head	*pos, *pos1;
703 	struct sctp_sockaddr_entry *saddr;
704 	int 			i;
705 	int 			retval = 0;
706 
707 	if (!sctp_addip_enable)
708 		return retval;
709 
710 	sp = sctp_sk(sk);
711 	ep = sp->ep;
712 
713 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
714 			  __FUNCTION__, sk, addrs, addrcnt);
715 
716 	list_for_each(pos, &ep->asocs) {
717 		asoc = list_entry(pos, struct sctp_association, asocs);
718 
719 		if (!asoc->peer.asconf_capable)
720 			continue;
721 
722 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
723 			continue;
724 
725 		if (!sctp_state(asoc, ESTABLISHED))
726 			continue;
727 
728 		/* Check if any address in the packed array of addresses is
729 		 * not present in the bind address list of the association.
730 		 * If so, do not send the asconf chunk to its peer, but
731 		 * continue with other associations.
732 		 */
733 		addr_buf = addrs;
734 		for (i = 0; i < addrcnt; i++) {
735 			laddr = (union sctp_addr *)addr_buf;
736 			af = sctp_get_af_specific(laddr->v4.sin_family);
737 			if (!af) {
738 				retval = -EINVAL;
739 				goto out;
740 			}
741 
742 			if (!sctp_assoc_lookup_laddr(asoc, laddr))
743 				break;
744 
745 			addr_buf += af->sockaddr_len;
746 		}
747 		if (i < addrcnt)
748 			continue;
749 
750 		/* Find one address in the association's bind address list
751 		 * that is not in the packed array of addresses. This is to
752 		 * make sure that we do not delete all the addresses in the
753 		 * association.
754 		 */
755 		bp = &asoc->base.bind_addr;
756 		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
757 					       addrcnt, sp);
758 		if (!laddr)
759 			continue;
760 
761 		/* We do not need RCU protection throughout this loop
762 		 * because this is done under a socket lock from the
763 		 * setsockopt call.
764 		 */
765 		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
766 						   SCTP_PARAM_DEL_IP);
767 		if (!chunk) {
768 			retval = -ENOMEM;
769 			goto out;
770 		}
771 
772 		/* Reset use_as_src flag for the addresses in the bind address
773 		 * list that are to be deleted.
774 		 */
775 		addr_buf = addrs;
776 		for (i = 0; i < addrcnt; i++) {
777 			laddr = (union sctp_addr *)addr_buf;
778 			af = sctp_get_af_specific(laddr->v4.sin_family);
779 			list_for_each_entry(saddr, &bp->address_list, list) {
780 				if (sctp_cmp_addr_exact(&saddr->a, laddr))
781 					saddr->state = SCTP_ADDR_DEL;
782 			}
783 			addr_buf += af->sockaddr_len;
784 		}
785 
786 		/* Update the route and saddr entries for all the transports
787 		 * as some of the addresses in the bind address list are
788 		 * about to be deleted and cannot be used as source addresses.
789 		 */
790 		list_for_each(pos1, &asoc->peer.transport_addr_list) {
791 			transport = list_entry(pos1, struct sctp_transport,
792 					       transports);
793 			dst_release(transport->dst);
794 			sctp_transport_route(transport, NULL,
795 					     sctp_sk(asoc->base.sk));
796 		}
797 
798 		retval = sctp_send_asconf(asoc, chunk);
799 	}
800 out:
801 	return retval;
802 }
803 
804 /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
805  *
806  * API 8.1
807  * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt,
808  *                int flags);
809  *
810  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
811  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
812  * or IPv6 addresses.
813  *
814  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
815  * Section 3.1.2 for this usage.
816  *
817  * addrs is a pointer to an array of one or more socket addresses. Each
818  * address is contained in its appropriate structure (i.e. struct
819  * sockaddr_in or struct sockaddr_in6) the family of the address type
820  * must be used to distinguish the address length (note that this
821  * representation is termed a "packed array" of addresses). The caller
822  * specifies the number of addresses in the array with addrcnt.
823  *
824  * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns
825  * -1, and sets errno to the appropriate error code.
826  *
827  * For SCTP, the port given in each socket address must be the same, or
828  * sctp_bindx() will fail, setting errno to EINVAL.
829  *
830  * The flags parameter is formed from the bitwise OR of zero or more of
831  * the following currently defined flags:
832  *
833  * SCTP_BINDX_ADD_ADDR
834  *
835  * SCTP_BINDX_REM_ADDR
836  *
837  * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
838  * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given
839  * addresses from the association. The two flags are mutually exclusive;
840  * if both are given, sctp_bindx() will fail with EINVAL. A caller may
841  * not remove all addresses from an association; sctp_bindx() will
842  * reject such an attempt with EINVAL.
843  *
844  * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
845  * additional addresses with an endpoint after calling bind().  Or use
846  * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
847  * socket is associated with so that no new association accepted will be
848  * associated with those addresses. If the endpoint supports dynamic
849  * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
850  * endpoint to send the appropriate message to the peer to change the
851  * peers address lists.
852  *
853  * Adding and removing addresses from a connected association is
854  * optional functionality. Implementations that do not support this
855  * functionality should return EOPNOTSUPP.
856  *
857  * Basically do nothing but copying the addresses from user to kernel
858  * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
859  * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
860  * from userspace.
861  *
862  * We don't use copy_from_user() for optimization: we first do the
863  * sanity checks (buffer size -fast- and access check-healthy
864  * pointer); if all of those succeed, then we can alloc the memory
865  * (expensive operation) needed to copy the data to kernel. Then we do
866  * the copying without checking the user space area
867  * (__copy_from_user()).
868  *
869  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
870  * it.
871  *
872  * sk        The sk of the socket
873  * addrs     The pointer to the addresses in user land
874  * addrssize Size of the addrs buffer
875  * op        Operation to perform (add or remove, see the flags of
876  *           sctp_bindx)
877  *
878  * Returns 0 if ok, <0 errno code on error.
879  */
880 SCTP_STATIC int sctp_setsockopt_bindx(struct sock* sk,
881 				      struct sockaddr __user *addrs,
882 				      int addrs_size, int op)
883 {
884 	struct sockaddr *kaddrs;
885 	int err;
886 	int addrcnt = 0;
887 	int walk_size = 0;
888 	struct sockaddr *sa_addr;
889 	void *addr_buf;
890 	struct sctp_af *af;
891 
892 	SCTP_DEBUG_PRINTK("sctp_setsocktopt_bindx: sk %p addrs %p"
893 			  " addrs_size %d opt %d\n", sk, addrs, addrs_size, op);
894 
895 	if (unlikely(addrs_size <= 0))
896 		return -EINVAL;
897 
898 	/* Check the user passed a healthy pointer.  */
899 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
900 		return -EFAULT;
901 
902 	/* Alloc space for the address array in kernel memory.  */
903 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
904 	if (unlikely(!kaddrs))
905 		return -ENOMEM;
906 
907 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
908 		kfree(kaddrs);
909 		return -EFAULT;
910 	}
911 
912 	/* Walk through the addrs buffer and count the number of addresses. */
913 	addr_buf = kaddrs;
914 	while (walk_size < addrs_size) {
915 		sa_addr = (struct sockaddr *)addr_buf;
916 		af = sctp_get_af_specific(sa_addr->sa_family);
917 
918 		/* If the address family is not supported or if this address
919 		 * causes the address buffer to overflow return EINVAL.
920 		 */
921 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
922 			kfree(kaddrs);
923 			return -EINVAL;
924 		}
925 		addrcnt++;
926 		addr_buf += af->sockaddr_len;
927 		walk_size += af->sockaddr_len;
928 	}
929 
930 	/* Do the work. */
931 	switch (op) {
932 	case SCTP_BINDX_ADD_ADDR:
933 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
934 		if (err)
935 			goto out;
936 		err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
937 		break;
938 
939 	case SCTP_BINDX_REM_ADDR:
940 		err = sctp_bindx_rem(sk, kaddrs, addrcnt);
941 		if (err)
942 			goto out;
943 		err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
944 		break;
945 
946 	default:
947 		err = -EINVAL;
948 		break;
949 	}
950 
951 out:
952 	kfree(kaddrs);
953 
954 	return err;
955 }
956 
957 /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
958  *
959  * Common routine for handling connect() and sctp_connectx().
960  * Connect will come in with just a single address.
961  */
962 static int __sctp_connect(struct sock* sk,
963 			  struct sockaddr *kaddrs,
964 			  int addrs_size)
965 {
966 	struct sctp_sock *sp;
967 	struct sctp_endpoint *ep;
968 	struct sctp_association *asoc = NULL;
969 	struct sctp_association *asoc2;
970 	struct sctp_transport *transport;
971 	union sctp_addr to;
972 	struct sctp_af *af;
973 	sctp_scope_t scope;
974 	long timeo;
975 	int err = 0;
976 	int addrcnt = 0;
977 	int walk_size = 0;
978 	union sctp_addr *sa_addr = NULL;
979 	void *addr_buf;
980 	unsigned short port;
981 	unsigned int f_flags = 0;
982 
983 	sp = sctp_sk(sk);
984 	ep = sp->ep;
985 
986 	/* connect() cannot be done on a socket that is already in ESTABLISHED
987 	 * state - UDP-style peeled off socket or a TCP-style socket that
988 	 * is already connected.
989 	 * It cannot be done even on a TCP-style listening socket.
990 	 */
991 	if (sctp_sstate(sk, ESTABLISHED) ||
992 	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
993 		err = -EISCONN;
994 		goto out_free;
995 	}
996 
997 	/* Walk through the addrs buffer and count the number of addresses. */
998 	addr_buf = kaddrs;
999 	while (walk_size < addrs_size) {
1000 		sa_addr = (union sctp_addr *)addr_buf;
1001 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
1002 		port = ntohs(sa_addr->v4.sin_port);
1003 
1004 		/* If the address family is not supported or if this address
1005 		 * causes the address buffer to overflow return EINVAL.
1006 		 */
1007 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1008 			err = -EINVAL;
1009 			goto out_free;
1010 		}
1011 
1012 		/* Save current address so we can work with it */
1013 		memcpy(&to, sa_addr, af->sockaddr_len);
1014 
1015 		err = sctp_verify_addr(sk, &to, af->sockaddr_len);
1016 		if (err)
1017 			goto out_free;
1018 
1019 		/* Make sure the destination port is correctly set
1020 		 * in all addresses.
1021 		 */
1022 		if (asoc && asoc->peer.port && asoc->peer.port != port)
1023 			goto out_free;
1024 
1025 
1026 		/* Check if there already is a matching association on the
1027 		 * endpoint (other than the one created here).
1028 		 */
1029 		asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1030 		if (asoc2 && asoc2 != asoc) {
1031 			if (asoc2->state >= SCTP_STATE_ESTABLISHED)
1032 				err = -EISCONN;
1033 			else
1034 				err = -EALREADY;
1035 			goto out_free;
1036 		}
1037 
1038 		/* If we could not find a matching association on the endpoint,
1039 		 * make sure that there is no peeled-off association matching
1040 		 * the peer address even on another socket.
1041 		 */
1042 		if (sctp_endpoint_is_peeled_off(ep, &to)) {
1043 			err = -EADDRNOTAVAIL;
1044 			goto out_free;
1045 		}
1046 
1047 		if (!asoc) {
1048 			/* If a bind() or sctp_bindx() is not called prior to
1049 			 * an sctp_connectx() call, the system picks an
1050 			 * ephemeral port and will choose an address set
1051 			 * equivalent to binding with a wildcard address.
1052 			 */
1053 			if (!ep->base.bind_addr.port) {
1054 				if (sctp_autobind(sk)) {
1055 					err = -EAGAIN;
1056 					goto out_free;
1057 				}
1058 			} else {
1059 				/*
1060 				 * If an unprivileged user inherits a 1-many
1061 				 * style socket with open associations on a
1062 				 * privileged port, it MAY be permitted to
1063 				 * accept new associations, but it SHOULD NOT
1064 				 * be permitted to open new associations.
1065 				 */
1066 				if (ep->base.bind_addr.port < PROT_SOCK &&
1067 				    !capable(CAP_NET_BIND_SERVICE)) {
1068 					err = -EACCES;
1069 					goto out_free;
1070 				}
1071 			}
1072 
1073 			scope = sctp_scope(&to);
1074 			asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1075 			if (!asoc) {
1076 				err = -ENOMEM;
1077 				goto out_free;
1078 			}
1079 		}
1080 
1081 		/* Prime the peer's transport structures.  */
1082 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL,
1083 						SCTP_UNKNOWN);
1084 		if (!transport) {
1085 			err = -ENOMEM;
1086 			goto out_free;
1087 		}
1088 
1089 		addrcnt++;
1090 		addr_buf += af->sockaddr_len;
1091 		walk_size += af->sockaddr_len;
1092 	}
1093 
1094 	err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
1095 	if (err < 0) {
1096 		goto out_free;
1097 	}
1098 
1099 	err = sctp_primitive_ASSOCIATE(asoc, NULL);
1100 	if (err < 0) {
1101 		goto out_free;
1102 	}
1103 
1104 	/* Initialize sk's dport and daddr for getpeername() */
1105 	inet_sk(sk)->dport = htons(asoc->peer.port);
1106 	af = sctp_get_af_specific(sa_addr->sa.sa_family);
1107 	af->to_sk_daddr(sa_addr, sk);
1108 	sk->sk_err = 0;
1109 
1110 	/* in-kernel sockets don't generally have a file allocated to them
1111 	 * if all they do is call sock_create_kern().
1112 	 */
1113 	if (sk->sk_socket->file)
1114 		f_flags = sk->sk_socket->file->f_flags;
1115 
1116 	timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK);
1117 
1118 	err = sctp_wait_for_connect(asoc, &timeo);
1119 
1120 	/* Don't free association on exit. */
1121 	asoc = NULL;
1122 
1123 out_free:
1124 
1125 	SCTP_DEBUG_PRINTK("About to exit __sctp_connect() free asoc: %p"
1126 			  " kaddrs: %p err: %d\n",
1127 			  asoc, kaddrs, err);
1128 	if (asoc)
1129 		sctp_association_free(asoc);
1130 	return err;
1131 }
1132 
1133 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
1134  *
1135  * API 8.9
1136  * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt);
1137  *
1138  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
1139  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
1140  * or IPv6 addresses.
1141  *
1142  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
1143  * Section 3.1.2 for this usage.
1144  *
1145  * addrs is a pointer to an array of one or more socket addresses. Each
1146  * address is contained in its appropriate structure (i.e. struct
1147  * sockaddr_in or struct sockaddr_in6) the family of the address type
1148  * must be used to distengish the address length (note that this
1149  * representation is termed a "packed array" of addresses). The caller
1150  * specifies the number of addresses in the array with addrcnt.
1151  *
1152  * On success, sctp_connectx() returns 0. On failure, sctp_connectx() returns
1153  * -1, and sets errno to the appropriate error code.
1154  *
1155  * For SCTP, the port given in each socket address must be the same, or
1156  * sctp_connectx() will fail, setting errno to EINVAL.
1157  *
1158  * An application can use sctp_connectx to initiate an association with
1159  * an endpoint that is multi-homed.  Much like sctp_bindx() this call
1160  * allows a caller to specify multiple addresses at which a peer can be
1161  * reached.  The way the SCTP stack uses the list of addresses to set up
1162  * the association is implementation dependant.  This function only
1163  * specifies that the stack will try to make use of all the addresses in
1164  * the list when needed.
1165  *
1166  * Note that the list of addresses passed in is only used for setting up
1167  * the association.  It does not necessarily equal the set of addresses
1168  * the peer uses for the resulting association.  If the caller wants to
1169  * find out the set of peer addresses, it must use sctp_getpaddrs() to
1170  * retrieve them after the association has been set up.
1171  *
1172  * Basically do nothing but copying the addresses from user to kernel
1173  * land and invoking either sctp_connectx(). This is used for tunneling
1174  * the sctp_connectx() request through sctp_setsockopt() from userspace.
1175  *
1176  * We don't use copy_from_user() for optimization: we first do the
1177  * sanity checks (buffer size -fast- and access check-healthy
1178  * pointer); if all of those succeed, then we can alloc the memory
1179  * (expensive operation) needed to copy the data to kernel. Then we do
1180  * the copying without checking the user space area
1181  * (__copy_from_user()).
1182  *
1183  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
1184  * it.
1185  *
1186  * sk        The sk of the socket
1187  * addrs     The pointer to the addresses in user land
1188  * addrssize Size of the addrs buffer
1189  *
1190  * Returns 0 if ok, <0 errno code on error.
1191  */
1192 SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
1193 				      struct sockaddr __user *addrs,
1194 				      int addrs_size)
1195 {
1196 	int err = 0;
1197 	struct sockaddr *kaddrs;
1198 
1199 	SCTP_DEBUG_PRINTK("%s - sk %p addrs %p addrs_size %d\n",
1200 			  __FUNCTION__, sk, addrs, addrs_size);
1201 
1202 	if (unlikely(addrs_size <= 0))
1203 		return -EINVAL;
1204 
1205 	/* Check the user passed a healthy pointer.  */
1206 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
1207 		return -EFAULT;
1208 
1209 	/* Alloc space for the address array in kernel memory.  */
1210 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
1211 	if (unlikely(!kaddrs))
1212 		return -ENOMEM;
1213 
1214 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
1215 		err = -EFAULT;
1216 	} else {
1217 		err = __sctp_connect(sk, kaddrs, addrs_size);
1218 	}
1219 
1220 	kfree(kaddrs);
1221 	return err;
1222 }
1223 
1224 /* API 3.1.4 close() - UDP Style Syntax
1225  * Applications use close() to perform graceful shutdown (as described in
1226  * Section 10.1 of [SCTP]) on ALL the associations currently represented
1227  * by a UDP-style socket.
1228  *
1229  * The syntax is
1230  *
1231  *   ret = close(int sd);
1232  *
1233  *   sd      - the socket descriptor of the associations to be closed.
1234  *
1235  * To gracefully shutdown a specific association represented by the
1236  * UDP-style socket, an application should use the sendmsg() call,
1237  * passing no user data, but including the appropriate flag in the
1238  * ancillary data (see Section xxxx).
1239  *
1240  * If sd in the close() call is a branched-off socket representing only
1241  * one association, the shutdown is performed on that association only.
1242  *
1243  * 4.1.6 close() - TCP Style Syntax
1244  *
1245  * Applications use close() to gracefully close down an association.
1246  *
1247  * The syntax is:
1248  *
1249  *    int close(int sd);
1250  *
1251  *      sd      - the socket descriptor of the association to be closed.
1252  *
1253  * After an application calls close() on a socket descriptor, no further
1254  * socket operations will succeed on that descriptor.
1255  *
1256  * API 7.1.4 SO_LINGER
1257  *
1258  * An application using the TCP-style socket can use this option to
1259  * perform the SCTP ABORT primitive.  The linger option structure is:
1260  *
1261  *  struct  linger {
1262  *     int     l_onoff;                // option on/off
1263  *     int     l_linger;               // linger time
1264  * };
1265  *
1266  * To enable the option, set l_onoff to 1.  If the l_linger value is set
1267  * to 0, calling close() is the same as the ABORT primitive.  If the
1268  * value is set to a negative value, the setsockopt() call will return
1269  * an error.  If the value is set to a positive value linger_time, the
1270  * close() can be blocked for at most linger_time ms.  If the graceful
1271  * shutdown phase does not finish during this period, close() will
1272  * return but the graceful shutdown phase continues in the system.
1273  */
1274 SCTP_STATIC void sctp_close(struct sock *sk, long timeout)
1275 {
1276 	struct sctp_endpoint *ep;
1277 	struct sctp_association *asoc;
1278 	struct list_head *pos, *temp;
1279 
1280 	SCTP_DEBUG_PRINTK("sctp_close(sk: 0x%p, timeout:%ld)\n", sk, timeout);
1281 
1282 	sctp_lock_sock(sk);
1283 	sk->sk_shutdown = SHUTDOWN_MASK;
1284 
1285 	ep = sctp_sk(sk)->ep;
1286 
1287 	/* Walk all associations on an endpoint.  */
1288 	list_for_each_safe(pos, temp, &ep->asocs) {
1289 		asoc = list_entry(pos, struct sctp_association, asocs);
1290 
1291 		if (sctp_style(sk, TCP)) {
1292 			/* A closed association can still be in the list if
1293 			 * it belongs to a TCP-style listening socket that is
1294 			 * not yet accepted. If so, free it. If not, send an
1295 			 * ABORT or SHUTDOWN based on the linger options.
1296 			 */
1297 			if (sctp_state(asoc, CLOSED)) {
1298 				sctp_unhash_established(asoc);
1299 				sctp_association_free(asoc);
1300 				continue;
1301 			}
1302 		}
1303 
1304 		if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
1305 			struct sctp_chunk *chunk;
1306 
1307 			chunk = sctp_make_abort_user(asoc, NULL, 0);
1308 			if (chunk)
1309 				sctp_primitive_ABORT(asoc, chunk);
1310 		} else
1311 			sctp_primitive_SHUTDOWN(asoc, NULL);
1312 	}
1313 
1314 	/* Clean up any skbs sitting on the receive queue.  */
1315 	sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
1316 	sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
1317 
1318 	/* On a TCP-style socket, block for at most linger_time if set. */
1319 	if (sctp_style(sk, TCP) && timeout)
1320 		sctp_wait_for_close(sk, timeout);
1321 
1322 	/* This will run the backlog queue.  */
1323 	sctp_release_sock(sk);
1324 
1325 	/* Supposedly, no process has access to the socket, but
1326 	 * the net layers still may.
1327 	 */
1328 	sctp_local_bh_disable();
1329 	sctp_bh_lock_sock(sk);
1330 
1331 	/* Hold the sock, since sk_common_release() will put sock_put()
1332 	 * and we have just a little more cleanup.
1333 	 */
1334 	sock_hold(sk);
1335 	sk_common_release(sk);
1336 
1337 	sctp_bh_unlock_sock(sk);
1338 	sctp_local_bh_enable();
1339 
1340 	sock_put(sk);
1341 
1342 	SCTP_DBG_OBJCNT_DEC(sock);
1343 }
1344 
1345 /* Handle EPIPE error. */
1346 static int sctp_error(struct sock *sk, int flags, int err)
1347 {
1348 	if (err == -EPIPE)
1349 		err = sock_error(sk) ? : -EPIPE;
1350 	if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
1351 		send_sig(SIGPIPE, current, 0);
1352 	return err;
1353 }
1354 
1355 /* API 3.1.3 sendmsg() - UDP Style Syntax
1356  *
1357  * An application uses sendmsg() and recvmsg() calls to transmit data to
1358  * and receive data from its peer.
1359  *
1360  *  ssize_t sendmsg(int socket, const struct msghdr *message,
1361  *                  int flags);
1362  *
1363  *  socket  - the socket descriptor of the endpoint.
1364  *  message - pointer to the msghdr structure which contains a single
1365  *            user message and possibly some ancillary data.
1366  *
1367  *            See Section 5 for complete description of the data
1368  *            structures.
1369  *
1370  *  flags   - flags sent or received with the user message, see Section
1371  *            5 for complete description of the flags.
1372  *
1373  * Note:  This function could use a rewrite especially when explicit
1374  * connect support comes in.
1375  */
1376 /* BUG:  We do not implement the equivalent of sk_stream_wait_memory(). */
1377 
1378 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
1379 
1380 SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
1381 			     struct msghdr *msg, size_t msg_len)
1382 {
1383 	struct sctp_sock *sp;
1384 	struct sctp_endpoint *ep;
1385 	struct sctp_association *new_asoc=NULL, *asoc=NULL;
1386 	struct sctp_transport *transport, *chunk_tp;
1387 	struct sctp_chunk *chunk;
1388 	union sctp_addr to;
1389 	struct sockaddr *msg_name = NULL;
1390 	struct sctp_sndrcvinfo default_sinfo = { 0 };
1391 	struct sctp_sndrcvinfo *sinfo;
1392 	struct sctp_initmsg *sinit;
1393 	sctp_assoc_t associd = 0;
1394 	sctp_cmsgs_t cmsgs = { NULL };
1395 	int err;
1396 	sctp_scope_t scope;
1397 	long timeo;
1398 	__u16 sinfo_flags = 0;
1399 	struct sctp_datamsg *datamsg;
1400 	struct list_head *pos;
1401 	int msg_flags = msg->msg_flags;
1402 
1403 	SCTP_DEBUG_PRINTK("sctp_sendmsg(sk: %p, msg: %p, msg_len: %zu)\n",
1404 			  sk, msg, msg_len);
1405 
1406 	err = 0;
1407 	sp = sctp_sk(sk);
1408 	ep = sp->ep;
1409 
1410 	SCTP_DEBUG_PRINTK("Using endpoint: %p.\n", ep);
1411 
1412 	/* We cannot send a message over a TCP-style listening socket. */
1413 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) {
1414 		err = -EPIPE;
1415 		goto out_nounlock;
1416 	}
1417 
1418 	/* Parse out the SCTP CMSGs.  */
1419 	err = sctp_msghdr_parse(msg, &cmsgs);
1420 
1421 	if (err) {
1422 		SCTP_DEBUG_PRINTK("msghdr parse err = %x\n", err);
1423 		goto out_nounlock;
1424 	}
1425 
1426 	/* Fetch the destination address for this packet.  This
1427 	 * address only selects the association--it is not necessarily
1428 	 * the address we will send to.
1429 	 * For a peeled-off socket, msg_name is ignored.
1430 	 */
1431 	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
1432 		int msg_namelen = msg->msg_namelen;
1433 
1434 		err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
1435 				       msg_namelen);
1436 		if (err)
1437 			return err;
1438 
1439 		if (msg_namelen > sizeof(to))
1440 			msg_namelen = sizeof(to);
1441 		memcpy(&to, msg->msg_name, msg_namelen);
1442 		msg_name = msg->msg_name;
1443 	}
1444 
1445 	sinfo = cmsgs.info;
1446 	sinit = cmsgs.init;
1447 
1448 	/* Did the user specify SNDRCVINFO?  */
1449 	if (sinfo) {
1450 		sinfo_flags = sinfo->sinfo_flags;
1451 		associd = sinfo->sinfo_assoc_id;
1452 	}
1453 
1454 	SCTP_DEBUG_PRINTK("msg_len: %zu, sinfo_flags: 0x%x\n",
1455 			  msg_len, sinfo_flags);
1456 
1457 	/* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */
1458 	if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) {
1459 		err = -EINVAL;
1460 		goto out_nounlock;
1461 	}
1462 
1463 	/* If SCTP_EOF is set, no data can be sent. Disallow sending zero
1464 	 * length messages when SCTP_EOF|SCTP_ABORT is not set.
1465 	 * If SCTP_ABORT is set, the message length could be non zero with
1466 	 * the msg_iov set to the user abort reason.
1467 	 */
1468 	if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) ||
1469 	    (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) {
1470 		err = -EINVAL;
1471 		goto out_nounlock;
1472 	}
1473 
1474 	/* If SCTP_ADDR_OVER is set, there must be an address
1475 	 * specified in msg_name.
1476 	 */
1477 	if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) {
1478 		err = -EINVAL;
1479 		goto out_nounlock;
1480 	}
1481 
1482 	transport = NULL;
1483 
1484 	SCTP_DEBUG_PRINTK("About to look up association.\n");
1485 
1486 	sctp_lock_sock(sk);
1487 
1488 	/* If a msg_name has been specified, assume this is to be used.  */
1489 	if (msg_name) {
1490 		/* Look for a matching association on the endpoint. */
1491 		asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1492 		if (!asoc) {
1493 			/* If we could not find a matching association on the
1494 			 * endpoint, make sure that it is not a TCP-style
1495 			 * socket that already has an association or there is
1496 			 * no peeled-off association on another socket.
1497 			 */
1498 			if ((sctp_style(sk, TCP) &&
1499 			     sctp_sstate(sk, ESTABLISHED)) ||
1500 			    sctp_endpoint_is_peeled_off(ep, &to)) {
1501 				err = -EADDRNOTAVAIL;
1502 				goto out_unlock;
1503 			}
1504 		}
1505 	} else {
1506 		asoc = sctp_id2assoc(sk, associd);
1507 		if (!asoc) {
1508 			err = -EPIPE;
1509 			goto out_unlock;
1510 		}
1511 	}
1512 
1513 	if (asoc) {
1514 		SCTP_DEBUG_PRINTK("Just looked up association: %p.\n", asoc);
1515 
1516 		/* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED
1517 		 * socket that has an association in CLOSED state. This can
1518 		 * happen when an accepted socket has an association that is
1519 		 * already CLOSED.
1520 		 */
1521 		if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) {
1522 			err = -EPIPE;
1523 			goto out_unlock;
1524 		}
1525 
1526 		if (sinfo_flags & SCTP_EOF) {
1527 			SCTP_DEBUG_PRINTK("Shutting down association: %p\n",
1528 					  asoc);
1529 			sctp_primitive_SHUTDOWN(asoc, NULL);
1530 			err = 0;
1531 			goto out_unlock;
1532 		}
1533 		if (sinfo_flags & SCTP_ABORT) {
1534 
1535 			chunk = sctp_make_abort_user(asoc, msg, msg_len);
1536 			if (!chunk) {
1537 				err = -ENOMEM;
1538 				goto out_unlock;
1539 			}
1540 
1541 			SCTP_DEBUG_PRINTK("Aborting association: %p\n", asoc);
1542 			sctp_primitive_ABORT(asoc, chunk);
1543 			err = 0;
1544 			goto out_unlock;
1545 		}
1546 	}
1547 
1548 	/* Do we need to create the association?  */
1549 	if (!asoc) {
1550 		SCTP_DEBUG_PRINTK("There is no association yet.\n");
1551 
1552 		if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) {
1553 			err = -EINVAL;
1554 			goto out_unlock;
1555 		}
1556 
1557 		/* Check for invalid stream against the stream counts,
1558 		 * either the default or the user specified stream counts.
1559 		 */
1560 		if (sinfo) {
1561 			if (!sinit || (sinit && !sinit->sinit_num_ostreams)) {
1562 				/* Check against the defaults. */
1563 				if (sinfo->sinfo_stream >=
1564 				    sp->initmsg.sinit_num_ostreams) {
1565 					err = -EINVAL;
1566 					goto out_unlock;
1567 				}
1568 			} else {
1569 				/* Check against the requested.  */
1570 				if (sinfo->sinfo_stream >=
1571 				    sinit->sinit_num_ostreams) {
1572 					err = -EINVAL;
1573 					goto out_unlock;
1574 				}
1575 			}
1576 		}
1577 
1578 		/*
1579 		 * API 3.1.2 bind() - UDP Style Syntax
1580 		 * If a bind() or sctp_bindx() is not called prior to a
1581 		 * sendmsg() call that initiates a new association, the
1582 		 * system picks an ephemeral port and will choose an address
1583 		 * set equivalent to binding with a wildcard address.
1584 		 */
1585 		if (!ep->base.bind_addr.port) {
1586 			if (sctp_autobind(sk)) {
1587 				err = -EAGAIN;
1588 				goto out_unlock;
1589 			}
1590 		} else {
1591 			/*
1592 			 * If an unprivileged user inherits a one-to-many
1593 			 * style socket with open associations on a privileged
1594 			 * port, it MAY be permitted to accept new associations,
1595 			 * but it SHOULD NOT be permitted to open new
1596 			 * associations.
1597 			 */
1598 			if (ep->base.bind_addr.port < PROT_SOCK &&
1599 			    !capable(CAP_NET_BIND_SERVICE)) {
1600 				err = -EACCES;
1601 				goto out_unlock;
1602 			}
1603 		}
1604 
1605 		scope = sctp_scope(&to);
1606 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1607 		if (!new_asoc) {
1608 			err = -ENOMEM;
1609 			goto out_unlock;
1610 		}
1611 		asoc = new_asoc;
1612 
1613 		/* If the SCTP_INIT ancillary data is specified, set all
1614 		 * the association init values accordingly.
1615 		 */
1616 		if (sinit) {
1617 			if (sinit->sinit_num_ostreams) {
1618 				asoc->c.sinit_num_ostreams =
1619 					sinit->sinit_num_ostreams;
1620 			}
1621 			if (sinit->sinit_max_instreams) {
1622 				asoc->c.sinit_max_instreams =
1623 					sinit->sinit_max_instreams;
1624 			}
1625 			if (sinit->sinit_max_attempts) {
1626 				asoc->max_init_attempts
1627 					= sinit->sinit_max_attempts;
1628 			}
1629 			if (sinit->sinit_max_init_timeo) {
1630 				asoc->max_init_timeo =
1631 				 msecs_to_jiffies(sinit->sinit_max_init_timeo);
1632 			}
1633 		}
1634 
1635 		/* Prime the peer's transport structures.  */
1636 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN);
1637 		if (!transport) {
1638 			err = -ENOMEM;
1639 			goto out_free;
1640 		}
1641 		err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
1642 		if (err < 0) {
1643 			err = -ENOMEM;
1644 			goto out_free;
1645 		}
1646 	}
1647 
1648 	/* ASSERT: we have a valid association at this point.  */
1649 	SCTP_DEBUG_PRINTK("We have a valid association.\n");
1650 
1651 	if (!sinfo) {
1652 		/* If the user didn't specify SNDRCVINFO, make up one with
1653 		 * some defaults.
1654 		 */
1655 		default_sinfo.sinfo_stream = asoc->default_stream;
1656 		default_sinfo.sinfo_flags = asoc->default_flags;
1657 		default_sinfo.sinfo_ppid = asoc->default_ppid;
1658 		default_sinfo.sinfo_context = asoc->default_context;
1659 		default_sinfo.sinfo_timetolive = asoc->default_timetolive;
1660 		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
1661 		sinfo = &default_sinfo;
1662 	}
1663 
1664 	/* API 7.1.7, the sndbuf size per association bounds the
1665 	 * maximum size of data that can be sent in a single send call.
1666 	 */
1667 	if (msg_len > sk->sk_sndbuf) {
1668 		err = -EMSGSIZE;
1669 		goto out_free;
1670 	}
1671 
1672 	if (asoc->pmtu_pending)
1673 		sctp_assoc_pending_pmtu(asoc);
1674 
1675 	/* If fragmentation is disabled and the message length exceeds the
1676 	 * association fragmentation point, return EMSGSIZE.  The I-D
1677 	 * does not specify what this error is, but this looks like
1678 	 * a great fit.
1679 	 */
1680 	if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
1681 		err = -EMSGSIZE;
1682 		goto out_free;
1683 	}
1684 
1685 	if (sinfo) {
1686 		/* Check for invalid stream. */
1687 		if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) {
1688 			err = -EINVAL;
1689 			goto out_free;
1690 		}
1691 	}
1692 
1693 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1694 	if (!sctp_wspace(asoc)) {
1695 		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
1696 		if (err)
1697 			goto out_free;
1698 	}
1699 
1700 	/* If an address is passed with the sendto/sendmsg call, it is used
1701 	 * to override the primary destination address in the TCP model, or
1702 	 * when SCTP_ADDR_OVER flag is set in the UDP model.
1703 	 */
1704 	if ((sctp_style(sk, TCP) && msg_name) ||
1705 	    (sinfo_flags & SCTP_ADDR_OVER)) {
1706 		chunk_tp = sctp_assoc_lookup_paddr(asoc, &to);
1707 		if (!chunk_tp) {
1708 			err = -EINVAL;
1709 			goto out_free;
1710 		}
1711 	} else
1712 		chunk_tp = NULL;
1713 
1714 	/* Auto-connect, if we aren't connected already. */
1715 	if (sctp_state(asoc, CLOSED)) {
1716 		err = sctp_primitive_ASSOCIATE(asoc, NULL);
1717 		if (err < 0)
1718 			goto out_free;
1719 		SCTP_DEBUG_PRINTK("We associated primitively.\n");
1720 	}
1721 
1722 	/* Break the message into multiple chunks of maximum size. */
1723 	datamsg = sctp_datamsg_from_user(asoc, sinfo, msg, msg_len);
1724 	if (!datamsg) {
1725 		err = -ENOMEM;
1726 		goto out_free;
1727 	}
1728 
1729 	/* Now send the (possibly) fragmented message. */
1730 	list_for_each(pos, &datamsg->chunks) {
1731 		chunk = list_entry(pos, struct sctp_chunk, frag_list);
1732 		sctp_datamsg_track(chunk);
1733 
1734 		/* Do accounting for the write space.  */
1735 		sctp_set_owner_w(chunk);
1736 
1737 		chunk->transport = chunk_tp;
1738 
1739 		/* Send it to the lower layers.  Note:  all chunks
1740 		 * must either fail or succeed.   The lower layer
1741 		 * works that way today.  Keep it that way or this
1742 		 * breaks.
1743 		 */
1744 		err = sctp_primitive_SEND(asoc, chunk);
1745 		/* Did the lower layer accept the chunk? */
1746 		if (err)
1747 			sctp_chunk_free(chunk);
1748 		SCTP_DEBUG_PRINTK("We sent primitively.\n");
1749 	}
1750 
1751 	sctp_datamsg_free(datamsg);
1752 	if (err)
1753 		goto out_free;
1754 	else
1755 		err = msg_len;
1756 
1757 	/* If we are already past ASSOCIATE, the lower
1758 	 * layers are responsible for association cleanup.
1759 	 */
1760 	goto out_unlock;
1761 
1762 out_free:
1763 	if (new_asoc)
1764 		sctp_association_free(asoc);
1765 out_unlock:
1766 	sctp_release_sock(sk);
1767 
1768 out_nounlock:
1769 	return sctp_error(sk, msg_flags, err);
1770 
1771 #if 0
1772 do_sock_err:
1773 	if (msg_len)
1774 		err = msg_len;
1775 	else
1776 		err = sock_error(sk);
1777 	goto out;
1778 
1779 do_interrupted:
1780 	if (msg_len)
1781 		err = msg_len;
1782 	goto out;
1783 #endif /* 0 */
1784 }
1785 
1786 /* This is an extended version of skb_pull() that removes the data from the
1787  * start of a skb even when data is spread across the list of skb's in the
1788  * frag_list. len specifies the total amount of data that needs to be removed.
1789  * when 'len' bytes could be removed from the skb, it returns 0.
1790  * If 'len' exceeds the total skb length,  it returns the no. of bytes that
1791  * could not be removed.
1792  */
1793 static int sctp_skb_pull(struct sk_buff *skb, int len)
1794 {
1795 	struct sk_buff *list;
1796 	int skb_len = skb_headlen(skb);
1797 	int rlen;
1798 
1799 	if (len <= skb_len) {
1800 		__skb_pull(skb, len);
1801 		return 0;
1802 	}
1803 	len -= skb_len;
1804 	__skb_pull(skb, skb_len);
1805 
1806 	for (list = skb_shinfo(skb)->frag_list; list; list = list->next) {
1807 		rlen = sctp_skb_pull(list, len);
1808 		skb->len -= (len-rlen);
1809 		skb->data_len -= (len-rlen);
1810 
1811 		if (!rlen)
1812 			return 0;
1813 
1814 		len = rlen;
1815 	}
1816 
1817 	return len;
1818 }
1819 
1820 /* API 3.1.3  recvmsg() - UDP Style Syntax
1821  *
1822  *  ssize_t recvmsg(int socket, struct msghdr *message,
1823  *                    int flags);
1824  *
1825  *  socket  - the socket descriptor of the endpoint.
1826  *  message - pointer to the msghdr structure which contains a single
1827  *            user message and possibly some ancillary data.
1828  *
1829  *            See Section 5 for complete description of the data
1830  *            structures.
1831  *
1832  *  flags   - flags sent or received with the user message, see Section
1833  *            5 for complete description of the flags.
1834  */
1835 static struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);
1836 
1837 SCTP_STATIC int sctp_recvmsg(struct kiocb *iocb, struct sock *sk,
1838 			     struct msghdr *msg, size_t len, int noblock,
1839 			     int flags, int *addr_len)
1840 {
1841 	struct sctp_ulpevent *event = NULL;
1842 	struct sctp_sock *sp = sctp_sk(sk);
1843 	struct sk_buff *skb;
1844 	int copied;
1845 	int err = 0;
1846 	int skb_len;
1847 
1848 	SCTP_DEBUG_PRINTK("sctp_recvmsg(%s: %p, %s: %p, %s: %zd, %s: %d, %s: "
1849 			  "0x%x, %s: %p)\n", "sk", sk, "msghdr", msg,
1850 			  "len", len, "knoblauch", noblock,
1851 			  "flags", flags, "addr_len", addr_len);
1852 
1853 	sctp_lock_sock(sk);
1854 
1855 	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED)) {
1856 		err = -ENOTCONN;
1857 		goto out;
1858 	}
1859 
1860 	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
1861 	if (!skb)
1862 		goto out;
1863 
1864 	/* Get the total length of the skb including any skb's in the
1865 	 * frag_list.
1866 	 */
1867 	skb_len = skb->len;
1868 
1869 	copied = skb_len;
1870 	if (copied > len)
1871 		copied = len;
1872 
1873 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1874 
1875 	event = sctp_skb2event(skb);
1876 
1877 	if (err)
1878 		goto out_free;
1879 
1880 	sock_recv_timestamp(msg, sk, skb);
1881 	if (sctp_ulpevent_is_notification(event)) {
1882 		msg->msg_flags |= MSG_NOTIFICATION;
1883 		sp->pf->event_msgname(event, msg->msg_name, addr_len);
1884 	} else {
1885 		sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
1886 	}
1887 
1888 	/* Check if we allow SCTP_SNDRCVINFO. */
1889 	if (sp->subscribe.sctp_data_io_event)
1890 		sctp_ulpevent_read_sndrcvinfo(event, msg);
1891 #if 0
1892 	/* FIXME: we should be calling IP/IPv6 layers.  */
1893 	if (sk->sk_protinfo.af_inet.cmsg_flags)
1894 		ip_cmsg_recv(msg, skb);
1895 #endif
1896 
1897 	err = copied;
1898 
1899 	/* If skb's length exceeds the user's buffer, update the skb and
1900 	 * push it back to the receive_queue so that the next call to
1901 	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
1902 	 */
1903 	if (skb_len > copied) {
1904 		msg->msg_flags &= ~MSG_EOR;
1905 		if (flags & MSG_PEEK)
1906 			goto out_free;
1907 		sctp_skb_pull(skb, copied);
1908 		skb_queue_head(&sk->sk_receive_queue, skb);
1909 
1910 		/* When only partial message is copied to the user, increase
1911 		 * rwnd by that amount. If all the data in the skb is read,
1912 		 * rwnd is updated when the event is freed.
1913 		 */
1914 		if (!sctp_ulpevent_is_notification(event))
1915 			sctp_assoc_rwnd_increase(event->asoc, copied);
1916 		goto out;
1917 	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
1918 		   (event->msg_flags & MSG_EOR))
1919 		msg->msg_flags |= MSG_EOR;
1920 	else
1921 		msg->msg_flags &= ~MSG_EOR;
1922 
1923 out_free:
1924 	if (flags & MSG_PEEK) {
1925 		/* Release the skb reference acquired after peeking the skb in
1926 		 * sctp_skb_recv_datagram().
1927 		 */
1928 		kfree_skb(skb);
1929 	} else {
1930 		/* Free the event which includes releasing the reference to
1931 		 * the owner of the skb, freeing the skb and updating the
1932 		 * rwnd.
1933 		 */
1934 		sctp_ulpevent_free(event);
1935 	}
1936 out:
1937 	sctp_release_sock(sk);
1938 	return err;
1939 }
1940 
1941 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
1942  *
1943  * This option is a on/off flag.  If enabled no SCTP message
1944  * fragmentation will be performed.  Instead if a message being sent
1945  * exceeds the current PMTU size, the message will NOT be sent and
1946  * instead a error will be indicated to the user.
1947  */
1948 static int sctp_setsockopt_disable_fragments(struct sock *sk,
1949 					    char __user *optval, int optlen)
1950 {
1951 	int val;
1952 
1953 	if (optlen < sizeof(int))
1954 		return -EINVAL;
1955 
1956 	if (get_user(val, (int __user *)optval))
1957 		return -EFAULT;
1958 
1959 	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
1960 
1961 	return 0;
1962 }
1963 
1964 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
1965 					int optlen)
1966 {
1967 	if (optlen != sizeof(struct sctp_event_subscribe))
1968 		return -EINVAL;
1969 	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
1970 		return -EFAULT;
1971 	return 0;
1972 }
1973 
1974 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
1975  *
1976  * This socket option is applicable to the UDP-style socket only.  When
1977  * set it will cause associations that are idle for more than the
1978  * specified number of seconds to automatically close.  An association
1979  * being idle is defined an association that has NOT sent or received
1980  * user data.  The special value of '0' indicates that no automatic
1981  * close of any associations should be performed.  The option expects an
1982  * integer defining the number of seconds of idle time before an
1983  * association is closed.
1984  */
1985 static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
1986 					    int optlen)
1987 {
1988 	struct sctp_sock *sp = sctp_sk(sk);
1989 
1990 	/* Applicable to UDP-style socket only */
1991 	if (sctp_style(sk, TCP))
1992 		return -EOPNOTSUPP;
1993 	if (optlen != sizeof(int))
1994 		return -EINVAL;
1995 	if (copy_from_user(&sp->autoclose, optval, optlen))
1996 		return -EFAULT;
1997 
1998 	return 0;
1999 }
2000 
2001 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
2002  *
2003  * Applications can enable or disable heartbeats for any peer address of
2004  * an association, modify an address's heartbeat interval, force a
2005  * heartbeat to be sent immediately, and adjust the address's maximum
2006  * number of retransmissions sent before an address is considered
2007  * unreachable.  The following structure is used to access and modify an
2008  * address's parameters:
2009  *
2010  *  struct sctp_paddrparams {
2011  *     sctp_assoc_t            spp_assoc_id;
2012  *     struct sockaddr_storage spp_address;
2013  *     uint32_t                spp_hbinterval;
2014  *     uint16_t                spp_pathmaxrxt;
2015  *     uint32_t                spp_pathmtu;
2016  *     uint32_t                spp_sackdelay;
2017  *     uint32_t                spp_flags;
2018  * };
2019  *
2020  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
2021  *                     application, and identifies the association for
2022  *                     this query.
2023  *   spp_address     - This specifies which address is of interest.
2024  *   spp_hbinterval  - This contains the value of the heartbeat interval,
2025  *                     in milliseconds.  If a  value of zero
2026  *                     is present in this field then no changes are to
2027  *                     be made to this parameter.
2028  *   spp_pathmaxrxt  - This contains the maximum number of
2029  *                     retransmissions before this address shall be
2030  *                     considered unreachable. If a  value of zero
2031  *                     is present in this field then no changes are to
2032  *                     be made to this parameter.
2033  *   spp_pathmtu     - When Path MTU discovery is disabled the value
2034  *                     specified here will be the "fixed" path mtu.
2035  *                     Note that if the spp_address field is empty
2036  *                     then all associations on this address will
2037  *                     have this fixed path mtu set upon them.
2038  *
2039  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
2040  *                     the number of milliseconds that sacks will be delayed
2041  *                     for. This value will apply to all addresses of an
2042  *                     association if the spp_address field is empty. Note
2043  *                     also, that if delayed sack is enabled and this
2044  *                     value is set to 0, no change is made to the last
2045  *                     recorded delayed sack timer value.
2046  *
2047  *   spp_flags       - These flags are used to control various features
2048  *                     on an association. The flag field may contain
2049  *                     zero or more of the following options.
2050  *
2051  *                     SPP_HB_ENABLE  - Enable heartbeats on the
2052  *                     specified address. Note that if the address
2053  *                     field is empty all addresses for the association
2054  *                     have heartbeats enabled upon them.
2055  *
2056  *                     SPP_HB_DISABLE - Disable heartbeats on the
2057  *                     speicifed address. Note that if the address
2058  *                     field is empty all addresses for the association
2059  *                     will have their heartbeats disabled. Note also
2060  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
2061  *                     mutually exclusive, only one of these two should
2062  *                     be specified. Enabling both fields will have
2063  *                     undetermined results.
2064  *
2065  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
2066  *                     to be made immediately.
2067  *
2068  *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
2069  *                     heartbeat delayis to be set to the value of 0
2070  *                     milliseconds.
2071  *
2072  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
2073  *                     discovery upon the specified address. Note that
2074  *                     if the address feild is empty then all addresses
2075  *                     on the association are effected.
2076  *
2077  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
2078  *                     discovery upon the specified address. Note that
2079  *                     if the address feild is empty then all addresses
2080  *                     on the association are effected. Not also that
2081  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
2082  *                     exclusive. Enabling both will have undetermined
2083  *                     results.
2084  *
2085  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
2086  *                     on delayed sack. The time specified in spp_sackdelay
2087  *                     is used to specify the sack delay for this address. Note
2088  *                     that if spp_address is empty then all addresses will
2089  *                     enable delayed sack and take on the sack delay
2090  *                     value specified in spp_sackdelay.
2091  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
2092  *                     off delayed sack. If the spp_address field is blank then
2093  *                     delayed sack is disabled for the entire association. Note
2094  *                     also that this field is mutually exclusive to
2095  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
2096  *                     results.
2097  */
2098 static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
2099 				       struct sctp_transport   *trans,
2100 				       struct sctp_association *asoc,
2101 				       struct sctp_sock        *sp,
2102 				       int                      hb_change,
2103 				       int                      pmtud_change,
2104 				       int                      sackdelay_change)
2105 {
2106 	int error;
2107 
2108 	if (params->spp_flags & SPP_HB_DEMAND && trans) {
2109 		error = sctp_primitive_REQUESTHEARTBEAT (trans->asoc, trans);
2110 		if (error)
2111 			return error;
2112 	}
2113 
2114 	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
2115 	 * this field is ignored.  Note also that a value of zero indicates
2116 	 * the current setting should be left unchanged.
2117 	 */
2118 	if (params->spp_flags & SPP_HB_ENABLE) {
2119 
2120 		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
2121 		 * set.  This lets us use 0 value when this flag
2122 		 * is set.
2123 		 */
2124 		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
2125 			params->spp_hbinterval = 0;
2126 
2127 		if (params->spp_hbinterval ||
2128 		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
2129 			if (trans) {
2130 				trans->hbinterval =
2131 				    msecs_to_jiffies(params->spp_hbinterval);
2132 			} else if (asoc) {
2133 				asoc->hbinterval =
2134 				    msecs_to_jiffies(params->spp_hbinterval);
2135 			} else {
2136 				sp->hbinterval = params->spp_hbinterval;
2137 			}
2138 		}
2139 	}
2140 
2141 	if (hb_change) {
2142 		if (trans) {
2143 			trans->param_flags =
2144 				(trans->param_flags & ~SPP_HB) | hb_change;
2145 		} else if (asoc) {
2146 			asoc->param_flags =
2147 				(asoc->param_flags & ~SPP_HB) | hb_change;
2148 		} else {
2149 			sp->param_flags =
2150 				(sp->param_flags & ~SPP_HB) | hb_change;
2151 		}
2152 	}
2153 
2154 	/* When Path MTU discovery is disabled the value specified here will
2155 	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
2156 	 * include the flag SPP_PMTUD_DISABLE for this field to have any
2157 	 * effect).
2158 	 */
2159 	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
2160 		if (trans) {
2161 			trans->pathmtu = params->spp_pathmtu;
2162 			sctp_assoc_sync_pmtu(asoc);
2163 		} else if (asoc) {
2164 			asoc->pathmtu = params->spp_pathmtu;
2165 			sctp_frag_point(sp, params->spp_pathmtu);
2166 		} else {
2167 			sp->pathmtu = params->spp_pathmtu;
2168 		}
2169 	}
2170 
2171 	if (pmtud_change) {
2172 		if (trans) {
2173 			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
2174 				(params->spp_flags & SPP_PMTUD_ENABLE);
2175 			trans->param_flags =
2176 				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
2177 			if (update) {
2178 				sctp_transport_pmtu(trans);
2179 				sctp_assoc_sync_pmtu(asoc);
2180 			}
2181 		} else if (asoc) {
2182 			asoc->param_flags =
2183 				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
2184 		} else {
2185 			sp->param_flags =
2186 				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
2187 		}
2188 	}
2189 
2190 	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
2191 	 * value of this field is ignored.  Note also that a value of zero
2192 	 * indicates the current setting should be left unchanged.
2193 	 */
2194 	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
2195 		if (trans) {
2196 			trans->sackdelay =
2197 				msecs_to_jiffies(params->spp_sackdelay);
2198 		} else if (asoc) {
2199 			asoc->sackdelay =
2200 				msecs_to_jiffies(params->spp_sackdelay);
2201 		} else {
2202 			sp->sackdelay = params->spp_sackdelay;
2203 		}
2204 	}
2205 
2206 	if (sackdelay_change) {
2207 		if (trans) {
2208 			trans->param_flags =
2209 				(trans->param_flags & ~SPP_SACKDELAY) |
2210 				sackdelay_change;
2211 		} else if (asoc) {
2212 			asoc->param_flags =
2213 				(asoc->param_flags & ~SPP_SACKDELAY) |
2214 				sackdelay_change;
2215 		} else {
2216 			sp->param_flags =
2217 				(sp->param_flags & ~SPP_SACKDELAY) |
2218 				sackdelay_change;
2219 		}
2220 	}
2221 
2222 	/* Note that unless the spp_flag is set to SPP_PMTUD_ENABLE the value
2223 	 * of this field is ignored.  Note also that a value of zero
2224 	 * indicates the current setting should be left unchanged.
2225 	 */
2226 	if ((params->spp_flags & SPP_PMTUD_ENABLE) && params->spp_pathmaxrxt) {
2227 		if (trans) {
2228 			trans->pathmaxrxt = params->spp_pathmaxrxt;
2229 		} else if (asoc) {
2230 			asoc->pathmaxrxt = params->spp_pathmaxrxt;
2231 		} else {
2232 			sp->pathmaxrxt = params->spp_pathmaxrxt;
2233 		}
2234 	}
2235 
2236 	return 0;
2237 }
2238 
2239 static int sctp_setsockopt_peer_addr_params(struct sock *sk,
2240 					    char __user *optval, int optlen)
2241 {
2242 	struct sctp_paddrparams  params;
2243 	struct sctp_transport   *trans = NULL;
2244 	struct sctp_association *asoc = NULL;
2245 	struct sctp_sock        *sp = sctp_sk(sk);
2246 	int error;
2247 	int hb_change, pmtud_change, sackdelay_change;
2248 
2249 	if (optlen != sizeof(struct sctp_paddrparams))
2250 		return - EINVAL;
2251 
2252 	if (copy_from_user(&params, optval, optlen))
2253 		return -EFAULT;
2254 
2255 	/* Validate flags and value parameters. */
2256 	hb_change        = params.spp_flags & SPP_HB;
2257 	pmtud_change     = params.spp_flags & SPP_PMTUD;
2258 	sackdelay_change = params.spp_flags & SPP_SACKDELAY;
2259 
2260 	if (hb_change        == SPP_HB ||
2261 	    pmtud_change     == SPP_PMTUD ||
2262 	    sackdelay_change == SPP_SACKDELAY ||
2263 	    params.spp_sackdelay > 500 ||
2264 	    (params.spp_pathmtu
2265 	    && params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
2266 		return -EINVAL;
2267 
2268 	/* If an address other than INADDR_ANY is specified, and
2269 	 * no transport is found, then the request is invalid.
2270 	 */
2271 	if (!sctp_is_any(( union sctp_addr *)&params.spp_address)) {
2272 		trans = sctp_addr_id2transport(sk, &params.spp_address,
2273 					       params.spp_assoc_id);
2274 		if (!trans)
2275 			return -EINVAL;
2276 	}
2277 
2278 	/* Get association, if assoc_id != 0 and the socket is a one
2279 	 * to many style socket, and an association was not found, then
2280 	 * the id was invalid.
2281 	 */
2282 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
2283 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
2284 		return -EINVAL;
2285 
2286 	/* Heartbeat demand can only be sent on a transport or
2287 	 * association, but not a socket.
2288 	 */
2289 	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
2290 		return -EINVAL;
2291 
2292 	/* Process parameters. */
2293 	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2294 					    hb_change, pmtud_change,
2295 					    sackdelay_change);
2296 
2297 	if (error)
2298 		return error;
2299 
2300 	/* If changes are for association, also apply parameters to each
2301 	 * transport.
2302 	 */
2303 	if (!trans && asoc) {
2304 		struct list_head *pos;
2305 
2306 		list_for_each(pos, &asoc->peer.transport_addr_list) {
2307 			trans = list_entry(pos, struct sctp_transport,
2308 					   transports);
2309 			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2310 						    hb_change, pmtud_change,
2311 						    sackdelay_change);
2312 		}
2313 	}
2314 
2315 	return 0;
2316 }
2317 
2318 /* 7.1.23. Delayed Ack Timer (SCTP_DELAYED_ACK_TIME)
2319  *
2320  *   This options will get or set the delayed ack timer.  The time is set
2321  *   in milliseconds.  If the assoc_id is 0, then this sets or gets the
2322  *   endpoints default delayed ack timer value.  If the assoc_id field is
2323  *   non-zero, then the set or get effects the specified association.
2324  *
2325  *   struct sctp_assoc_value {
2326  *       sctp_assoc_t            assoc_id;
2327  *       uint32_t                assoc_value;
2328  *   };
2329  *
2330  *     assoc_id    - This parameter, indicates which association the
2331  *                   user is preforming an action upon. Note that if
2332  *                   this field's value is zero then the endpoints
2333  *                   default value is changed (effecting future
2334  *                   associations only).
2335  *
2336  *     assoc_value - This parameter contains the number of milliseconds
2337  *                   that the user is requesting the delayed ACK timer
2338  *                   be set to. Note that this value is defined in
2339  *                   the standard to be between 200 and 500 milliseconds.
2340  *
2341  *                   Note: a value of zero will leave the value alone,
2342  *                   but disable SACK delay. A non-zero value will also
2343  *                   enable SACK delay.
2344  */
2345 
2346 static int sctp_setsockopt_delayed_ack_time(struct sock *sk,
2347 					    char __user *optval, int optlen)
2348 {
2349 	struct sctp_assoc_value  params;
2350 	struct sctp_transport   *trans = NULL;
2351 	struct sctp_association *asoc = NULL;
2352 	struct sctp_sock        *sp = sctp_sk(sk);
2353 
2354 	if (optlen != sizeof(struct sctp_assoc_value))
2355 		return - EINVAL;
2356 
2357 	if (copy_from_user(&params, optval, optlen))
2358 		return -EFAULT;
2359 
2360 	/* Validate value parameter. */
2361 	if (params.assoc_value > 500)
2362 		return -EINVAL;
2363 
2364 	/* Get association, if assoc_id != 0 and the socket is a one
2365 	 * to many style socket, and an association was not found, then
2366 	 * the id was invalid.
2367 	 */
2368 	asoc = sctp_id2assoc(sk, params.assoc_id);
2369 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
2370 		return -EINVAL;
2371 
2372 	if (params.assoc_value) {
2373 		if (asoc) {
2374 			asoc->sackdelay =
2375 				msecs_to_jiffies(params.assoc_value);
2376 			asoc->param_flags =
2377 				(asoc->param_flags & ~SPP_SACKDELAY) |
2378 				SPP_SACKDELAY_ENABLE;
2379 		} else {
2380 			sp->sackdelay = params.assoc_value;
2381 			sp->param_flags =
2382 				(sp->param_flags & ~SPP_SACKDELAY) |
2383 				SPP_SACKDELAY_ENABLE;
2384 		}
2385 	} else {
2386 		if (asoc) {
2387 			asoc->param_flags =
2388 				(asoc->param_flags & ~SPP_SACKDELAY) |
2389 				SPP_SACKDELAY_DISABLE;
2390 		} else {
2391 			sp->param_flags =
2392 				(sp->param_flags & ~SPP_SACKDELAY) |
2393 				SPP_SACKDELAY_DISABLE;
2394 		}
2395 	}
2396 
2397 	/* If change is for association, also apply to each transport. */
2398 	if (asoc) {
2399 		struct list_head *pos;
2400 
2401 		list_for_each(pos, &asoc->peer.transport_addr_list) {
2402 			trans = list_entry(pos, struct sctp_transport,
2403 					   transports);
2404 			if (params.assoc_value) {
2405 				trans->sackdelay =
2406 					msecs_to_jiffies(params.assoc_value);
2407 				trans->param_flags =
2408 					(trans->param_flags & ~SPP_SACKDELAY) |
2409 					SPP_SACKDELAY_ENABLE;
2410 			} else {
2411 				trans->param_flags =
2412 					(trans->param_flags & ~SPP_SACKDELAY) |
2413 					SPP_SACKDELAY_DISABLE;
2414 			}
2415 		}
2416 	}
2417 
2418 	return 0;
2419 }
2420 
2421 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
2422  *
2423  * Applications can specify protocol parameters for the default association
2424  * initialization.  The option name argument to setsockopt() and getsockopt()
2425  * is SCTP_INITMSG.
2426  *
2427  * Setting initialization parameters is effective only on an unconnected
2428  * socket (for UDP-style sockets only future associations are effected
2429  * by the change).  With TCP-style sockets, this option is inherited by
2430  * sockets derived from a listener socket.
2431  */
2432 static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, int optlen)
2433 {
2434 	struct sctp_initmsg sinit;
2435 	struct sctp_sock *sp = sctp_sk(sk);
2436 
2437 	if (optlen != sizeof(struct sctp_initmsg))
2438 		return -EINVAL;
2439 	if (copy_from_user(&sinit, optval, optlen))
2440 		return -EFAULT;
2441 
2442 	if (sinit.sinit_num_ostreams)
2443 		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
2444 	if (sinit.sinit_max_instreams)
2445 		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
2446 	if (sinit.sinit_max_attempts)
2447 		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
2448 	if (sinit.sinit_max_init_timeo)
2449 		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
2450 
2451 	return 0;
2452 }
2453 
2454 /*
2455  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
2456  *
2457  *   Applications that wish to use the sendto() system call may wish to
2458  *   specify a default set of parameters that would normally be supplied
2459  *   through the inclusion of ancillary data.  This socket option allows
2460  *   such an application to set the default sctp_sndrcvinfo structure.
2461  *   The application that wishes to use this socket option simply passes
2462  *   in to this call the sctp_sndrcvinfo structure defined in Section
2463  *   5.2.2) The input parameters accepted by this call include
2464  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
2465  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
2466  *   to this call if the caller is using the UDP model.
2467  */
2468 static int sctp_setsockopt_default_send_param(struct sock *sk,
2469 						char __user *optval, int optlen)
2470 {
2471 	struct sctp_sndrcvinfo info;
2472 	struct sctp_association *asoc;
2473 	struct sctp_sock *sp = sctp_sk(sk);
2474 
2475 	if (optlen != sizeof(struct sctp_sndrcvinfo))
2476 		return -EINVAL;
2477 	if (copy_from_user(&info, optval, optlen))
2478 		return -EFAULT;
2479 
2480 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
2481 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
2482 		return -EINVAL;
2483 
2484 	if (asoc) {
2485 		asoc->default_stream = info.sinfo_stream;
2486 		asoc->default_flags = info.sinfo_flags;
2487 		asoc->default_ppid = info.sinfo_ppid;
2488 		asoc->default_context = info.sinfo_context;
2489 		asoc->default_timetolive = info.sinfo_timetolive;
2490 	} else {
2491 		sp->default_stream = info.sinfo_stream;
2492 		sp->default_flags = info.sinfo_flags;
2493 		sp->default_ppid = info.sinfo_ppid;
2494 		sp->default_context = info.sinfo_context;
2495 		sp->default_timetolive = info.sinfo_timetolive;
2496 	}
2497 
2498 	return 0;
2499 }
2500 
2501 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
2502  *
2503  * Requests that the local SCTP stack use the enclosed peer address as
2504  * the association primary.  The enclosed address must be one of the
2505  * association peer's addresses.
2506  */
2507 static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
2508 					int optlen)
2509 {
2510 	struct sctp_prim prim;
2511 	struct sctp_transport *trans;
2512 
2513 	if (optlen != sizeof(struct sctp_prim))
2514 		return -EINVAL;
2515 
2516 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
2517 		return -EFAULT;
2518 
2519 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
2520 	if (!trans)
2521 		return -EINVAL;
2522 
2523 	sctp_assoc_set_primary(trans->asoc, trans);
2524 
2525 	return 0;
2526 }
2527 
2528 /*
2529  * 7.1.5 SCTP_NODELAY
2530  *
2531  * Turn on/off any Nagle-like algorithm.  This means that packets are
2532  * generally sent as soon as possible and no unnecessary delays are
2533  * introduced, at the cost of more packets in the network.  Expects an
2534  *  integer boolean flag.
2535  */
2536 static int sctp_setsockopt_nodelay(struct sock *sk, char __user *optval,
2537 					int optlen)
2538 {
2539 	int val;
2540 
2541 	if (optlen < sizeof(int))
2542 		return -EINVAL;
2543 	if (get_user(val, (int __user *)optval))
2544 		return -EFAULT;
2545 
2546 	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
2547 	return 0;
2548 }
2549 
2550 /*
2551  *
2552  * 7.1.1 SCTP_RTOINFO
2553  *
2554  * The protocol parameters used to initialize and bound retransmission
2555  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
2556  * and modify these parameters.
2557  * All parameters are time values, in milliseconds.  A value of 0, when
2558  * modifying the parameters, indicates that the current value should not
2559  * be changed.
2560  *
2561  */
2562 static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, int optlen) {
2563 	struct sctp_rtoinfo rtoinfo;
2564 	struct sctp_association *asoc;
2565 
2566 	if (optlen != sizeof (struct sctp_rtoinfo))
2567 		return -EINVAL;
2568 
2569 	if (copy_from_user(&rtoinfo, optval, optlen))
2570 		return -EFAULT;
2571 
2572 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
2573 
2574 	/* Set the values to the specific association */
2575 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
2576 		return -EINVAL;
2577 
2578 	if (asoc) {
2579 		if (rtoinfo.srto_initial != 0)
2580 			asoc->rto_initial =
2581 				msecs_to_jiffies(rtoinfo.srto_initial);
2582 		if (rtoinfo.srto_max != 0)
2583 			asoc->rto_max = msecs_to_jiffies(rtoinfo.srto_max);
2584 		if (rtoinfo.srto_min != 0)
2585 			asoc->rto_min = msecs_to_jiffies(rtoinfo.srto_min);
2586 	} else {
2587 		/* If there is no association or the association-id = 0
2588 		 * set the values to the endpoint.
2589 		 */
2590 		struct sctp_sock *sp = sctp_sk(sk);
2591 
2592 		if (rtoinfo.srto_initial != 0)
2593 			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
2594 		if (rtoinfo.srto_max != 0)
2595 			sp->rtoinfo.srto_max = rtoinfo.srto_max;
2596 		if (rtoinfo.srto_min != 0)
2597 			sp->rtoinfo.srto_min = rtoinfo.srto_min;
2598 	}
2599 
2600 	return 0;
2601 }
2602 
2603 /*
2604  *
2605  * 7.1.2 SCTP_ASSOCINFO
2606  *
2607  * This option is used to tune the maximum retransmission attempts
2608  * of the association.
2609  * Returns an error if the new association retransmission value is
2610  * greater than the sum of the retransmission value  of the peer.
2611  * See [SCTP] for more information.
2612  *
2613  */
2614 static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, int optlen)
2615 {
2616 
2617 	struct sctp_assocparams assocparams;
2618 	struct sctp_association *asoc;
2619 
2620 	if (optlen != sizeof(struct sctp_assocparams))
2621 		return -EINVAL;
2622 	if (copy_from_user(&assocparams, optval, optlen))
2623 		return -EFAULT;
2624 
2625 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
2626 
2627 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
2628 		return -EINVAL;
2629 
2630 	/* Set the values to the specific association */
2631 	if (asoc) {
2632 		if (assocparams.sasoc_asocmaxrxt != 0) {
2633 			__u32 path_sum = 0;
2634 			int   paths = 0;
2635 			struct list_head *pos;
2636 			struct sctp_transport *peer_addr;
2637 
2638 			list_for_each(pos, &asoc->peer.transport_addr_list) {
2639 				peer_addr = list_entry(pos,
2640 						struct sctp_transport,
2641 						transports);
2642 				path_sum += peer_addr->pathmaxrxt;
2643 				paths++;
2644 			}
2645 
2646 			/* Only validate asocmaxrxt if we have more then
2647 			 * one path/transport.  We do this because path
2648 			 * retransmissions are only counted when we have more
2649 			 * then one path.
2650 			 */
2651 			if (paths > 1 &&
2652 			    assocparams.sasoc_asocmaxrxt > path_sum)
2653 				return -EINVAL;
2654 
2655 			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
2656 		}
2657 
2658 		if (assocparams.sasoc_cookie_life != 0) {
2659 			asoc->cookie_life.tv_sec =
2660 					assocparams.sasoc_cookie_life / 1000;
2661 			asoc->cookie_life.tv_usec =
2662 					(assocparams.sasoc_cookie_life % 1000)
2663 					* 1000;
2664 		}
2665 	} else {
2666 		/* Set the values to the endpoint */
2667 		struct sctp_sock *sp = sctp_sk(sk);
2668 
2669 		if (assocparams.sasoc_asocmaxrxt != 0)
2670 			sp->assocparams.sasoc_asocmaxrxt =
2671 						assocparams.sasoc_asocmaxrxt;
2672 		if (assocparams.sasoc_cookie_life != 0)
2673 			sp->assocparams.sasoc_cookie_life =
2674 						assocparams.sasoc_cookie_life;
2675 	}
2676 	return 0;
2677 }
2678 
2679 /*
2680  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
2681  *
2682  * This socket option is a boolean flag which turns on or off mapped V4
2683  * addresses.  If this option is turned on and the socket is type
2684  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
2685  * If this option is turned off, then no mapping will be done of V4
2686  * addresses and a user will receive both PF_INET6 and PF_INET type
2687  * addresses on the socket.
2688  */
2689 static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, int optlen)
2690 {
2691 	int val;
2692 	struct sctp_sock *sp = sctp_sk(sk);
2693 
2694 	if (optlen < sizeof(int))
2695 		return -EINVAL;
2696 	if (get_user(val, (int __user *)optval))
2697 		return -EFAULT;
2698 	if (val)
2699 		sp->v4mapped = 1;
2700 	else
2701 		sp->v4mapped = 0;
2702 
2703 	return 0;
2704 }
2705 
2706 /*
2707  * 7.1.17 Set the maximum fragrmentation size (SCTP_MAXSEG)
2708  *
2709  * This socket option specifies the maximum size to put in any outgoing
2710  * SCTP chunk.  If a message is larger than this size it will be
2711  * fragmented by SCTP into the specified size.  Note that the underlying
2712  * SCTP implementation may fragment into smaller sized chunks when the
2713  * PMTU of the underlying association is smaller than the value set by
2714  * the user.
2715  */
2716 static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, int optlen)
2717 {
2718 	struct sctp_association *asoc;
2719 	struct list_head *pos;
2720 	struct sctp_sock *sp = sctp_sk(sk);
2721 	int val;
2722 
2723 	if (optlen < sizeof(int))
2724 		return -EINVAL;
2725 	if (get_user(val, (int __user *)optval))
2726 		return -EFAULT;
2727 	if ((val != 0) && ((val < 8) || (val > SCTP_MAX_CHUNK_LEN)))
2728 		return -EINVAL;
2729 	sp->user_frag = val;
2730 
2731 	/* Update the frag_point of the existing associations. */
2732 	list_for_each(pos, &(sp->ep->asocs)) {
2733 		asoc = list_entry(pos, struct sctp_association, asocs);
2734 		asoc->frag_point = sctp_frag_point(sp, asoc->pathmtu);
2735 	}
2736 
2737 	return 0;
2738 }
2739 
2740 
2741 /*
2742  *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
2743  *
2744  *   Requests that the peer mark the enclosed address as the association
2745  *   primary. The enclosed address must be one of the association's
2746  *   locally bound addresses. The following structure is used to make a
2747  *   set primary request:
2748  */
2749 static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
2750 					     int optlen)
2751 {
2752 	struct sctp_sock	*sp;
2753 	struct sctp_endpoint	*ep;
2754 	struct sctp_association	*asoc = NULL;
2755 	struct sctp_setpeerprim	prim;
2756 	struct sctp_chunk	*chunk;
2757 	int 			err;
2758 
2759 	sp = sctp_sk(sk);
2760 	ep = sp->ep;
2761 
2762 	if (!sctp_addip_enable)
2763 		return -EPERM;
2764 
2765 	if (optlen != sizeof(struct sctp_setpeerprim))
2766 		return -EINVAL;
2767 
2768 	if (copy_from_user(&prim, optval, optlen))
2769 		return -EFAULT;
2770 
2771 	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
2772 	if (!asoc)
2773 		return -EINVAL;
2774 
2775 	if (!asoc->peer.asconf_capable)
2776 		return -EPERM;
2777 
2778 	if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
2779 		return -EPERM;
2780 
2781 	if (!sctp_state(asoc, ESTABLISHED))
2782 		return -ENOTCONN;
2783 
2784 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
2785 		return -EADDRNOTAVAIL;
2786 
2787 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
2788 	chunk = sctp_make_asconf_set_prim(asoc,
2789 					  (union sctp_addr *)&prim.sspp_addr);
2790 	if (!chunk)
2791 		return -ENOMEM;
2792 
2793 	err = sctp_send_asconf(asoc, chunk);
2794 
2795 	SCTP_DEBUG_PRINTK("We set peer primary addr primitively.\n");
2796 
2797 	return err;
2798 }
2799 
2800 static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
2801 					  int optlen)
2802 {
2803 	struct sctp_setadaptation adaptation;
2804 
2805 	if (optlen != sizeof(struct sctp_setadaptation))
2806 		return -EINVAL;
2807 	if (copy_from_user(&adaptation, optval, optlen))
2808 		return -EFAULT;
2809 
2810 	sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
2811 
2812 	return 0;
2813 }
2814 
2815 /*
2816  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
2817  *
2818  * The context field in the sctp_sndrcvinfo structure is normally only
2819  * used when a failed message is retrieved holding the value that was
2820  * sent down on the actual send call.  This option allows the setting of
2821  * a default context on an association basis that will be received on
2822  * reading messages from the peer.  This is especially helpful in the
2823  * one-2-many model for an application to keep some reference to an
2824  * internal state machine that is processing messages on the
2825  * association.  Note that the setting of this value only effects
2826  * received messages from the peer and does not effect the value that is
2827  * saved with outbound messages.
2828  */
2829 static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
2830 				   int optlen)
2831 {
2832 	struct sctp_assoc_value params;
2833 	struct sctp_sock *sp;
2834 	struct sctp_association *asoc;
2835 
2836 	if (optlen != sizeof(struct sctp_assoc_value))
2837 		return -EINVAL;
2838 	if (copy_from_user(&params, optval, optlen))
2839 		return -EFAULT;
2840 
2841 	sp = sctp_sk(sk);
2842 
2843 	if (params.assoc_id != 0) {
2844 		asoc = sctp_id2assoc(sk, params.assoc_id);
2845 		if (!asoc)
2846 			return -EINVAL;
2847 		asoc->default_rcv_context = params.assoc_value;
2848 	} else {
2849 		sp->default_rcv_context = params.assoc_value;
2850 	}
2851 
2852 	return 0;
2853 }
2854 
2855 /*
2856  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
2857  *
2858  * This options will at a minimum specify if the implementation is doing
2859  * fragmented interleave.  Fragmented interleave, for a one to many
2860  * socket, is when subsequent calls to receive a message may return
2861  * parts of messages from different associations.  Some implementations
2862  * may allow you to turn this value on or off.  If so, when turned off,
2863  * no fragment interleave will occur (which will cause a head of line
2864  * blocking amongst multiple associations sharing the same one to many
2865  * socket).  When this option is turned on, then each receive call may
2866  * come from a different association (thus the user must receive data
2867  * with the extended calls (e.g. sctp_recvmsg) to keep track of which
2868  * association each receive belongs to.
2869  *
2870  * This option takes a boolean value.  A non-zero value indicates that
2871  * fragmented interleave is on.  A value of zero indicates that
2872  * fragmented interleave is off.
2873  *
2874  * Note that it is important that an implementation that allows this
2875  * option to be turned on, have it off by default.  Otherwise an unaware
2876  * application using the one to many model may become confused and act
2877  * incorrectly.
2878  */
2879 static int sctp_setsockopt_fragment_interleave(struct sock *sk,
2880 					       char __user *optval,
2881 					       int optlen)
2882 {
2883 	int val;
2884 
2885 	if (optlen != sizeof(int))
2886 		return -EINVAL;
2887 	if (get_user(val, (int __user *)optval))
2888 		return -EFAULT;
2889 
2890 	sctp_sk(sk)->frag_interleave = (val == 0) ? 0 : 1;
2891 
2892 	return 0;
2893 }
2894 
2895 /*
2896  * 7.1.25.  Set or Get the sctp partial delivery point
2897  *       (SCTP_PARTIAL_DELIVERY_POINT)
2898  * This option will set or get the SCTP partial delivery point.  This
2899  * point is the size of a message where the partial delivery API will be
2900  * invoked to help free up rwnd space for the peer.  Setting this to a
2901  * lower value will cause partial delivery's to happen more often.  The
2902  * calls argument is an integer that sets or gets the partial delivery
2903  * point.
2904  */
2905 static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
2906 						  char __user *optval,
2907 						  int optlen)
2908 {
2909 	u32 val;
2910 
2911 	if (optlen != sizeof(u32))
2912 		return -EINVAL;
2913 	if (get_user(val, (int __user *)optval))
2914 		return -EFAULT;
2915 
2916 	sctp_sk(sk)->pd_point = val;
2917 
2918 	return 0; /* is this the right error code? */
2919 }
2920 
2921 /*
2922  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
2923  *
2924  * This option will allow a user to change the maximum burst of packets
2925  * that can be emitted by this association.  Note that the default value
2926  * is 4, and some implementations may restrict this setting so that it
2927  * can only be lowered.
2928  *
2929  * NOTE: This text doesn't seem right.  Do this on a socket basis with
2930  * future associations inheriting the socket value.
2931  */
2932 static int sctp_setsockopt_maxburst(struct sock *sk,
2933 				    char __user *optval,
2934 				    int optlen)
2935 {
2936 	int val;
2937 
2938 	if (optlen != sizeof(int))
2939 		return -EINVAL;
2940 	if (get_user(val, (int __user *)optval))
2941 		return -EFAULT;
2942 
2943 	if (val < 0)
2944 		return -EINVAL;
2945 
2946 	sctp_sk(sk)->max_burst = val;
2947 
2948 	return 0;
2949 }
2950 
2951 /*
2952  * 7.1.18.  Add a chunk that must be authenticated (SCTP_AUTH_CHUNK)
2953  *
2954  * This set option adds a chunk type that the user is requesting to be
2955  * received only in an authenticated way.  Changes to the list of chunks
2956  * will only effect future associations on the socket.
2957  */
2958 static int sctp_setsockopt_auth_chunk(struct sock *sk,
2959 				    char __user *optval,
2960 				    int optlen)
2961 {
2962 	struct sctp_authchunk val;
2963 
2964 	if (optlen != sizeof(struct sctp_authchunk))
2965 		return -EINVAL;
2966 	if (copy_from_user(&val, optval, optlen))
2967 		return -EFAULT;
2968 
2969 	switch (val.sauth_chunk) {
2970 		case SCTP_CID_INIT:
2971 		case SCTP_CID_INIT_ACK:
2972 		case SCTP_CID_SHUTDOWN_COMPLETE:
2973 		case SCTP_CID_AUTH:
2974 			return -EINVAL;
2975 	}
2976 
2977 	/* add this chunk id to the endpoint */
2978 	return sctp_auth_ep_add_chunkid(sctp_sk(sk)->ep, val.sauth_chunk);
2979 }
2980 
2981 /*
2982  * 7.1.19.  Get or set the list of supported HMAC Identifiers (SCTP_HMAC_IDENT)
2983  *
2984  * This option gets or sets the list of HMAC algorithms that the local
2985  * endpoint requires the peer to use.
2986  */
2987 static int sctp_setsockopt_hmac_ident(struct sock *sk,
2988 				    char __user *optval,
2989 				    int optlen)
2990 {
2991 	struct sctp_hmacalgo *hmacs;
2992 	int err;
2993 
2994 	if (optlen < sizeof(struct sctp_hmacalgo))
2995 		return -EINVAL;
2996 
2997 	hmacs = kmalloc(optlen, GFP_KERNEL);
2998 	if (!hmacs)
2999 		return -ENOMEM;
3000 
3001 	if (copy_from_user(hmacs, optval, optlen)) {
3002 		err = -EFAULT;
3003 		goto out;
3004 	}
3005 
3006 	if (hmacs->shmac_num_idents == 0 ||
3007 	    hmacs->shmac_num_idents > SCTP_AUTH_NUM_HMACS) {
3008 		err = -EINVAL;
3009 		goto out;
3010 	}
3011 
3012 	err = sctp_auth_ep_set_hmacs(sctp_sk(sk)->ep, hmacs);
3013 out:
3014 	kfree(hmacs);
3015 	return err;
3016 }
3017 
3018 /*
3019  * 7.1.20.  Set a shared key (SCTP_AUTH_KEY)
3020  *
3021  * This option will set a shared secret key which is used to build an
3022  * association shared key.
3023  */
3024 static int sctp_setsockopt_auth_key(struct sock *sk,
3025 				    char __user *optval,
3026 				    int optlen)
3027 {
3028 	struct sctp_authkey *authkey;
3029 	struct sctp_association *asoc;
3030 	int ret;
3031 
3032 	if (optlen <= sizeof(struct sctp_authkey))
3033 		return -EINVAL;
3034 
3035 	authkey = kmalloc(optlen, GFP_KERNEL);
3036 	if (!authkey)
3037 		return -ENOMEM;
3038 
3039 	if (copy_from_user(authkey, optval, optlen)) {
3040 		ret = -EFAULT;
3041 		goto out;
3042 	}
3043 
3044 	asoc = sctp_id2assoc(sk, authkey->sca_assoc_id);
3045 	if (!asoc && authkey->sca_assoc_id && sctp_style(sk, UDP)) {
3046 		ret = -EINVAL;
3047 		goto out;
3048 	}
3049 
3050 	ret = sctp_auth_set_key(sctp_sk(sk)->ep, asoc, authkey);
3051 out:
3052 	kfree(authkey);
3053 	return ret;
3054 }
3055 
3056 /*
3057  * 7.1.21.  Get or set the active shared key (SCTP_AUTH_ACTIVE_KEY)
3058  *
3059  * This option will get or set the active shared key to be used to build
3060  * the association shared key.
3061  */
3062 static int sctp_setsockopt_active_key(struct sock *sk,
3063 					char __user *optval,
3064 					int optlen)
3065 {
3066 	struct sctp_authkeyid val;
3067 	struct sctp_association *asoc;
3068 
3069 	if (optlen != sizeof(struct sctp_authkeyid))
3070 		return -EINVAL;
3071 	if (copy_from_user(&val, optval, optlen))
3072 		return -EFAULT;
3073 
3074 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3075 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3076 		return -EINVAL;
3077 
3078 	return sctp_auth_set_active_key(sctp_sk(sk)->ep, asoc,
3079 					val.scact_keynumber);
3080 }
3081 
3082 /*
3083  * 7.1.22.  Delete a shared key (SCTP_AUTH_DELETE_KEY)
3084  *
3085  * This set option will delete a shared secret key from use.
3086  */
3087 static int sctp_setsockopt_del_key(struct sock *sk,
3088 					char __user *optval,
3089 					int optlen)
3090 {
3091 	struct sctp_authkeyid val;
3092 	struct sctp_association *asoc;
3093 
3094 	if (optlen != sizeof(struct sctp_authkeyid))
3095 		return -EINVAL;
3096 	if (copy_from_user(&val, optval, optlen))
3097 		return -EFAULT;
3098 
3099 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3100 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3101 		return -EINVAL;
3102 
3103 	return sctp_auth_del_key_id(sctp_sk(sk)->ep, asoc,
3104 				    val.scact_keynumber);
3105 
3106 }
3107 
3108 
3109 /* API 6.2 setsockopt(), getsockopt()
3110  *
3111  * Applications use setsockopt() and getsockopt() to set or retrieve
3112  * socket options.  Socket options are used to change the default
3113  * behavior of sockets calls.  They are described in Section 7.
3114  *
3115  * The syntax is:
3116  *
3117  *   ret = getsockopt(int sd, int level, int optname, void __user *optval,
3118  *                    int __user *optlen);
3119  *   ret = setsockopt(int sd, int level, int optname, const void __user *optval,
3120  *                    int optlen);
3121  *
3122  *   sd      - the socket descript.
3123  *   level   - set to IPPROTO_SCTP for all SCTP options.
3124  *   optname - the option name.
3125  *   optval  - the buffer to store the value of the option.
3126  *   optlen  - the size of the buffer.
3127  */
3128 SCTP_STATIC int sctp_setsockopt(struct sock *sk, int level, int optname,
3129 				char __user *optval, int optlen)
3130 {
3131 	int retval = 0;
3132 
3133 	SCTP_DEBUG_PRINTK("sctp_setsockopt(sk: %p... optname: %d)\n",
3134 			  sk, optname);
3135 
3136 	/* I can hardly begin to describe how wrong this is.  This is
3137 	 * so broken as to be worse than useless.  The API draft
3138 	 * REALLY is NOT helpful here...  I am not convinced that the
3139 	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
3140 	 * are at all well-founded.
3141 	 */
3142 	if (level != SOL_SCTP) {
3143 		struct sctp_af *af = sctp_sk(sk)->pf->af;
3144 		retval = af->setsockopt(sk, level, optname, optval, optlen);
3145 		goto out_nounlock;
3146 	}
3147 
3148 	sctp_lock_sock(sk);
3149 
3150 	switch (optname) {
3151 	case SCTP_SOCKOPT_BINDX_ADD:
3152 		/* 'optlen' is the size of the addresses buffer. */
3153 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3154 					       optlen, SCTP_BINDX_ADD_ADDR);
3155 		break;
3156 
3157 	case SCTP_SOCKOPT_BINDX_REM:
3158 		/* 'optlen' is the size of the addresses buffer. */
3159 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3160 					       optlen, SCTP_BINDX_REM_ADDR);
3161 		break;
3162 
3163 	case SCTP_SOCKOPT_CONNECTX:
3164 		/* 'optlen' is the size of the addresses buffer. */
3165 		retval = sctp_setsockopt_connectx(sk, (struct sockaddr __user *)optval,
3166 					       optlen);
3167 		break;
3168 
3169 	case SCTP_DISABLE_FRAGMENTS:
3170 		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
3171 		break;
3172 
3173 	case SCTP_EVENTS:
3174 		retval = sctp_setsockopt_events(sk, optval, optlen);
3175 		break;
3176 
3177 	case SCTP_AUTOCLOSE:
3178 		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
3179 		break;
3180 
3181 	case SCTP_PEER_ADDR_PARAMS:
3182 		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
3183 		break;
3184 
3185 	case SCTP_DELAYED_ACK_TIME:
3186 		retval = sctp_setsockopt_delayed_ack_time(sk, optval, optlen);
3187 		break;
3188 	case SCTP_PARTIAL_DELIVERY_POINT:
3189 		retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
3190 		break;
3191 
3192 	case SCTP_INITMSG:
3193 		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
3194 		break;
3195 	case SCTP_DEFAULT_SEND_PARAM:
3196 		retval = sctp_setsockopt_default_send_param(sk, optval,
3197 							    optlen);
3198 		break;
3199 	case SCTP_PRIMARY_ADDR:
3200 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
3201 		break;
3202 	case SCTP_SET_PEER_PRIMARY_ADDR:
3203 		retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
3204 		break;
3205 	case SCTP_NODELAY:
3206 		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
3207 		break;
3208 	case SCTP_RTOINFO:
3209 		retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
3210 		break;
3211 	case SCTP_ASSOCINFO:
3212 		retval = sctp_setsockopt_associnfo(sk, optval, optlen);
3213 		break;
3214 	case SCTP_I_WANT_MAPPED_V4_ADDR:
3215 		retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
3216 		break;
3217 	case SCTP_MAXSEG:
3218 		retval = sctp_setsockopt_maxseg(sk, optval, optlen);
3219 		break;
3220 	case SCTP_ADAPTATION_LAYER:
3221 		retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
3222 		break;
3223 	case SCTP_CONTEXT:
3224 		retval = sctp_setsockopt_context(sk, optval, optlen);
3225 		break;
3226 	case SCTP_FRAGMENT_INTERLEAVE:
3227 		retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
3228 		break;
3229 	case SCTP_MAX_BURST:
3230 		retval = sctp_setsockopt_maxburst(sk, optval, optlen);
3231 		break;
3232 	case SCTP_AUTH_CHUNK:
3233 		retval = sctp_setsockopt_auth_chunk(sk, optval, optlen);
3234 		break;
3235 	case SCTP_HMAC_IDENT:
3236 		retval = sctp_setsockopt_hmac_ident(sk, optval, optlen);
3237 		break;
3238 	case SCTP_AUTH_KEY:
3239 		retval = sctp_setsockopt_auth_key(sk, optval, optlen);
3240 		break;
3241 	case SCTP_AUTH_ACTIVE_KEY:
3242 		retval = sctp_setsockopt_active_key(sk, optval, optlen);
3243 		break;
3244 	case SCTP_AUTH_DELETE_KEY:
3245 		retval = sctp_setsockopt_del_key(sk, optval, optlen);
3246 		break;
3247 	default:
3248 		retval = -ENOPROTOOPT;
3249 		break;
3250 	}
3251 
3252 	sctp_release_sock(sk);
3253 
3254 out_nounlock:
3255 	return retval;
3256 }
3257 
3258 /* API 3.1.6 connect() - UDP Style Syntax
3259  *
3260  * An application may use the connect() call in the UDP model to initiate an
3261  * association without sending data.
3262  *
3263  * The syntax is:
3264  *
3265  * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
3266  *
3267  * sd: the socket descriptor to have a new association added to.
3268  *
3269  * nam: the address structure (either struct sockaddr_in or struct
3270  *    sockaddr_in6 defined in RFC2553 [7]).
3271  *
3272  * len: the size of the address.
3273  */
3274 SCTP_STATIC int sctp_connect(struct sock *sk, struct sockaddr *addr,
3275 			     int addr_len)
3276 {
3277 	int err = 0;
3278 	struct sctp_af *af;
3279 
3280 	sctp_lock_sock(sk);
3281 
3282 	SCTP_DEBUG_PRINTK("%s - sk: %p, sockaddr: %p, addr_len: %d\n",
3283 			  __FUNCTION__, sk, addr, addr_len);
3284 
3285 	/* Validate addr_len before calling common connect/connectx routine. */
3286 	af = sctp_get_af_specific(addr->sa_family);
3287 	if (!af || addr_len < af->sockaddr_len) {
3288 		err = -EINVAL;
3289 	} else {
3290 		/* Pass correct addr len to common routine (so it knows there
3291 		 * is only one address being passed.
3292 		 */
3293 		err = __sctp_connect(sk, addr, af->sockaddr_len);
3294 	}
3295 
3296 	sctp_release_sock(sk);
3297 	return err;
3298 }
3299 
3300 /* FIXME: Write comments. */
3301 SCTP_STATIC int sctp_disconnect(struct sock *sk, int flags)
3302 {
3303 	return -EOPNOTSUPP; /* STUB */
3304 }
3305 
3306 /* 4.1.4 accept() - TCP Style Syntax
3307  *
3308  * Applications use accept() call to remove an established SCTP
3309  * association from the accept queue of the endpoint.  A new socket
3310  * descriptor will be returned from accept() to represent the newly
3311  * formed association.
3312  */
3313 SCTP_STATIC struct sock *sctp_accept(struct sock *sk, int flags, int *err)
3314 {
3315 	struct sctp_sock *sp;
3316 	struct sctp_endpoint *ep;
3317 	struct sock *newsk = NULL;
3318 	struct sctp_association *asoc;
3319 	long timeo;
3320 	int error = 0;
3321 
3322 	sctp_lock_sock(sk);
3323 
3324 	sp = sctp_sk(sk);
3325 	ep = sp->ep;
3326 
3327 	if (!sctp_style(sk, TCP)) {
3328 		error = -EOPNOTSUPP;
3329 		goto out;
3330 	}
3331 
3332 	if (!sctp_sstate(sk, LISTENING)) {
3333 		error = -EINVAL;
3334 		goto out;
3335 	}
3336 
3337 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
3338 
3339 	error = sctp_wait_for_accept(sk, timeo);
3340 	if (error)
3341 		goto out;
3342 
3343 	/* We treat the list of associations on the endpoint as the accept
3344 	 * queue and pick the first association on the list.
3345 	 */
3346 	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
3347 
3348 	newsk = sp->pf->create_accept_sk(sk, asoc);
3349 	if (!newsk) {
3350 		error = -ENOMEM;
3351 		goto out;
3352 	}
3353 
3354 	/* Populate the fields of the newsk from the oldsk and migrate the
3355 	 * asoc to the newsk.
3356 	 */
3357 	sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
3358 
3359 out:
3360 	sctp_release_sock(sk);
3361 	*err = error;
3362 	return newsk;
3363 }
3364 
3365 /* The SCTP ioctl handler. */
3366 SCTP_STATIC int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
3367 {
3368 	return -ENOIOCTLCMD;
3369 }
3370 
3371 /* This is the function which gets called during socket creation to
3372  * initialized the SCTP-specific portion of the sock.
3373  * The sock structure should already be zero-filled memory.
3374  */
3375 SCTP_STATIC int sctp_init_sock(struct sock *sk)
3376 {
3377 	struct sctp_endpoint *ep;
3378 	struct sctp_sock *sp;
3379 
3380 	SCTP_DEBUG_PRINTK("sctp_init_sock(sk: %p)\n", sk);
3381 
3382 	sp = sctp_sk(sk);
3383 
3384 	/* Initialize the SCTP per socket area.  */
3385 	switch (sk->sk_type) {
3386 	case SOCK_SEQPACKET:
3387 		sp->type = SCTP_SOCKET_UDP;
3388 		break;
3389 	case SOCK_STREAM:
3390 		sp->type = SCTP_SOCKET_TCP;
3391 		break;
3392 	default:
3393 		return -ESOCKTNOSUPPORT;
3394 	}
3395 
3396 	/* Initialize default send parameters. These parameters can be
3397 	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
3398 	 */
3399 	sp->default_stream = 0;
3400 	sp->default_ppid = 0;
3401 	sp->default_flags = 0;
3402 	sp->default_context = 0;
3403 	sp->default_timetolive = 0;
3404 
3405 	sp->default_rcv_context = 0;
3406 	sp->max_burst = sctp_max_burst;
3407 
3408 	/* Initialize default setup parameters. These parameters
3409 	 * can be modified with the SCTP_INITMSG socket option or
3410 	 * overridden by the SCTP_INIT CMSG.
3411 	 */
3412 	sp->initmsg.sinit_num_ostreams   = sctp_max_outstreams;
3413 	sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
3414 	sp->initmsg.sinit_max_attempts   = sctp_max_retrans_init;
3415 	sp->initmsg.sinit_max_init_timeo = sctp_rto_max;
3416 
3417 	/* Initialize default RTO related parameters.  These parameters can
3418 	 * be modified for with the SCTP_RTOINFO socket option.
3419 	 */
3420 	sp->rtoinfo.srto_initial = sctp_rto_initial;
3421 	sp->rtoinfo.srto_max     = sctp_rto_max;
3422 	sp->rtoinfo.srto_min     = sctp_rto_min;
3423 
3424 	/* Initialize default association related parameters. These parameters
3425 	 * can be modified with the SCTP_ASSOCINFO socket option.
3426 	 */
3427 	sp->assocparams.sasoc_asocmaxrxt = sctp_max_retrans_association;
3428 	sp->assocparams.sasoc_number_peer_destinations = 0;
3429 	sp->assocparams.sasoc_peer_rwnd = 0;
3430 	sp->assocparams.sasoc_local_rwnd = 0;
3431 	sp->assocparams.sasoc_cookie_life = sctp_valid_cookie_life;
3432 
3433 	/* Initialize default event subscriptions. By default, all the
3434 	 * options are off.
3435 	 */
3436 	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
3437 
3438 	/* Default Peer Address Parameters.  These defaults can
3439 	 * be modified via SCTP_PEER_ADDR_PARAMS
3440 	 */
3441 	sp->hbinterval  = sctp_hb_interval;
3442 	sp->pathmaxrxt  = sctp_max_retrans_path;
3443 	sp->pathmtu     = 0; // allow default discovery
3444 	sp->sackdelay   = sctp_sack_timeout;
3445 	sp->param_flags = SPP_HB_ENABLE |
3446 			  SPP_PMTUD_ENABLE |
3447 			  SPP_SACKDELAY_ENABLE;
3448 
3449 	/* If enabled no SCTP message fragmentation will be performed.
3450 	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
3451 	 */
3452 	sp->disable_fragments = 0;
3453 
3454 	/* Enable Nagle algorithm by default.  */
3455 	sp->nodelay           = 0;
3456 
3457 	/* Enable by default. */
3458 	sp->v4mapped          = 1;
3459 
3460 	/* Auto-close idle associations after the configured
3461 	 * number of seconds.  A value of 0 disables this
3462 	 * feature.  Configure through the SCTP_AUTOCLOSE socket option,
3463 	 * for UDP-style sockets only.
3464 	 */
3465 	sp->autoclose         = 0;
3466 
3467 	/* User specified fragmentation limit. */
3468 	sp->user_frag         = 0;
3469 
3470 	sp->adaptation_ind = 0;
3471 
3472 	sp->pf = sctp_get_pf_specific(sk->sk_family);
3473 
3474 	/* Control variables for partial data delivery. */
3475 	atomic_set(&sp->pd_mode, 0);
3476 	skb_queue_head_init(&sp->pd_lobby);
3477 	sp->frag_interleave = 0;
3478 
3479 	/* Create a per socket endpoint structure.  Even if we
3480 	 * change the data structure relationships, this may still
3481 	 * be useful for storing pre-connect address information.
3482 	 */
3483 	ep = sctp_endpoint_new(sk, GFP_KERNEL);
3484 	if (!ep)
3485 		return -ENOMEM;
3486 
3487 	sp->ep = ep;
3488 	sp->hmac = NULL;
3489 
3490 	SCTP_DBG_OBJCNT_INC(sock);
3491 	atomic_inc(&sctp_sockets_allocated);
3492 	return 0;
3493 }
3494 
3495 /* Cleanup any SCTP per socket resources.  */
3496 SCTP_STATIC int sctp_destroy_sock(struct sock *sk)
3497 {
3498 	struct sctp_endpoint *ep;
3499 
3500 	SCTP_DEBUG_PRINTK("sctp_destroy_sock(sk: %p)\n", sk);
3501 
3502 	/* Release our hold on the endpoint. */
3503 	ep = sctp_sk(sk)->ep;
3504 	sctp_endpoint_free(ep);
3505 	atomic_dec(&sctp_sockets_allocated);
3506 	return 0;
3507 }
3508 
3509 /* API 4.1.7 shutdown() - TCP Style Syntax
3510  *     int shutdown(int socket, int how);
3511  *
3512  *     sd      - the socket descriptor of the association to be closed.
3513  *     how     - Specifies the type of shutdown.  The  values  are
3514  *               as follows:
3515  *               SHUT_RD
3516  *                     Disables further receive operations. No SCTP
3517  *                     protocol action is taken.
3518  *               SHUT_WR
3519  *                     Disables further send operations, and initiates
3520  *                     the SCTP shutdown sequence.
3521  *               SHUT_RDWR
3522  *                     Disables further send  and  receive  operations
3523  *                     and initiates the SCTP shutdown sequence.
3524  */
3525 SCTP_STATIC void sctp_shutdown(struct sock *sk, int how)
3526 {
3527 	struct sctp_endpoint *ep;
3528 	struct sctp_association *asoc;
3529 
3530 	if (!sctp_style(sk, TCP))
3531 		return;
3532 
3533 	if (how & SEND_SHUTDOWN) {
3534 		ep = sctp_sk(sk)->ep;
3535 		if (!list_empty(&ep->asocs)) {
3536 			asoc = list_entry(ep->asocs.next,
3537 					  struct sctp_association, asocs);
3538 			sctp_primitive_SHUTDOWN(asoc, NULL);
3539 		}
3540 	}
3541 }
3542 
3543 /* 7.2.1 Association Status (SCTP_STATUS)
3544 
3545  * Applications can retrieve current status information about an
3546  * association, including association state, peer receiver window size,
3547  * number of unacked data chunks, and number of data chunks pending
3548  * receipt.  This information is read-only.
3549  */
3550 static int sctp_getsockopt_sctp_status(struct sock *sk, int len,
3551 				       char __user *optval,
3552 				       int __user *optlen)
3553 {
3554 	struct sctp_status status;
3555 	struct sctp_association *asoc = NULL;
3556 	struct sctp_transport *transport;
3557 	sctp_assoc_t associd;
3558 	int retval = 0;
3559 
3560 	if (len < sizeof(status)) {
3561 		retval = -EINVAL;
3562 		goto out;
3563 	}
3564 
3565 	len = sizeof(status);
3566 	if (copy_from_user(&status, optval, len)) {
3567 		retval = -EFAULT;
3568 		goto out;
3569 	}
3570 
3571 	associd = status.sstat_assoc_id;
3572 	asoc = sctp_id2assoc(sk, associd);
3573 	if (!asoc) {
3574 		retval = -EINVAL;
3575 		goto out;
3576 	}
3577 
3578 	transport = asoc->peer.primary_path;
3579 
3580 	status.sstat_assoc_id = sctp_assoc2id(asoc);
3581 	status.sstat_state = asoc->state;
3582 	status.sstat_rwnd =  asoc->peer.rwnd;
3583 	status.sstat_unackdata = asoc->unack_data;
3584 
3585 	status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
3586 	status.sstat_instrms = asoc->c.sinit_max_instreams;
3587 	status.sstat_outstrms = asoc->c.sinit_num_ostreams;
3588 	status.sstat_fragmentation_point = asoc->frag_point;
3589 	status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3590 	memcpy(&status.sstat_primary.spinfo_address, &transport->ipaddr,
3591 			transport->af_specific->sockaddr_len);
3592 	/* Map ipv4 address into v4-mapped-on-v6 address.  */
3593 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
3594 		(union sctp_addr *)&status.sstat_primary.spinfo_address);
3595 	status.sstat_primary.spinfo_state = transport->state;
3596 	status.sstat_primary.spinfo_cwnd = transport->cwnd;
3597 	status.sstat_primary.spinfo_srtt = transport->srtt;
3598 	status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
3599 	status.sstat_primary.spinfo_mtu = transport->pathmtu;
3600 
3601 	if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
3602 		status.sstat_primary.spinfo_state = SCTP_ACTIVE;
3603 
3604 	if (put_user(len, optlen)) {
3605 		retval = -EFAULT;
3606 		goto out;
3607 	}
3608 
3609 	SCTP_DEBUG_PRINTK("sctp_getsockopt_sctp_status(%d): %d %d %d\n",
3610 			  len, status.sstat_state, status.sstat_rwnd,
3611 			  status.sstat_assoc_id);
3612 
3613 	if (copy_to_user(optval, &status, len)) {
3614 		retval = -EFAULT;
3615 		goto out;
3616 	}
3617 
3618 out:
3619 	return (retval);
3620 }
3621 
3622 
3623 /* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
3624  *
3625  * Applications can retrieve information about a specific peer address
3626  * of an association, including its reachability state, congestion
3627  * window, and retransmission timer values.  This information is
3628  * read-only.
3629  */
3630 static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
3631 					  char __user *optval,
3632 					  int __user *optlen)
3633 {
3634 	struct sctp_paddrinfo pinfo;
3635 	struct sctp_transport *transport;
3636 	int retval = 0;
3637 
3638 	if (len < sizeof(pinfo)) {
3639 		retval = -EINVAL;
3640 		goto out;
3641 	}
3642 
3643 	len = sizeof(pinfo);
3644 	if (copy_from_user(&pinfo, optval, len)) {
3645 		retval = -EFAULT;
3646 		goto out;
3647 	}
3648 
3649 	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
3650 					   pinfo.spinfo_assoc_id);
3651 	if (!transport)
3652 		return -EINVAL;
3653 
3654 	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3655 	pinfo.spinfo_state = transport->state;
3656 	pinfo.spinfo_cwnd = transport->cwnd;
3657 	pinfo.spinfo_srtt = transport->srtt;
3658 	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
3659 	pinfo.spinfo_mtu = transport->pathmtu;
3660 
3661 	if (pinfo.spinfo_state == SCTP_UNKNOWN)
3662 		pinfo.spinfo_state = SCTP_ACTIVE;
3663 
3664 	if (put_user(len, optlen)) {
3665 		retval = -EFAULT;
3666 		goto out;
3667 	}
3668 
3669 	if (copy_to_user(optval, &pinfo, len)) {
3670 		retval = -EFAULT;
3671 		goto out;
3672 	}
3673 
3674 out:
3675 	return (retval);
3676 }
3677 
3678 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
3679  *
3680  * This option is a on/off flag.  If enabled no SCTP message
3681  * fragmentation will be performed.  Instead if a message being sent
3682  * exceeds the current PMTU size, the message will NOT be sent and
3683  * instead a error will be indicated to the user.
3684  */
3685 static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
3686 					char __user *optval, int __user *optlen)
3687 {
3688 	int val;
3689 
3690 	if (len < sizeof(int))
3691 		return -EINVAL;
3692 
3693 	len = sizeof(int);
3694 	val = (sctp_sk(sk)->disable_fragments == 1);
3695 	if (put_user(len, optlen))
3696 		return -EFAULT;
3697 	if (copy_to_user(optval, &val, len))
3698 		return -EFAULT;
3699 	return 0;
3700 }
3701 
3702 /* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
3703  *
3704  * This socket option is used to specify various notifications and
3705  * ancillary data the user wishes to receive.
3706  */
3707 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
3708 				  int __user *optlen)
3709 {
3710 	if (len < sizeof(struct sctp_event_subscribe))
3711 		return -EINVAL;
3712 	len = sizeof(struct sctp_event_subscribe);
3713 	if (put_user(len, optlen))
3714 		return -EFAULT;
3715 	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
3716 		return -EFAULT;
3717 	return 0;
3718 }
3719 
3720 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
3721  *
3722  * This socket option is applicable to the UDP-style socket only.  When
3723  * set it will cause associations that are idle for more than the
3724  * specified number of seconds to automatically close.  An association
3725  * being idle is defined an association that has NOT sent or received
3726  * user data.  The special value of '0' indicates that no automatic
3727  * close of any associations should be performed.  The option expects an
3728  * integer defining the number of seconds of idle time before an
3729  * association is closed.
3730  */
3731 static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
3732 {
3733 	/* Applicable to UDP-style socket only */
3734 	if (sctp_style(sk, TCP))
3735 		return -EOPNOTSUPP;
3736 	if (len < sizeof(int))
3737 		return -EINVAL;
3738 	len = sizeof(int);
3739 	if (put_user(len, optlen))
3740 		return -EFAULT;
3741 	if (copy_to_user(optval, &sctp_sk(sk)->autoclose, sizeof(int)))
3742 		return -EFAULT;
3743 	return 0;
3744 }
3745 
3746 /* Helper routine to branch off an association to a new socket.  */
3747 SCTP_STATIC int sctp_do_peeloff(struct sctp_association *asoc,
3748 				struct socket **sockp)
3749 {
3750 	struct sock *sk = asoc->base.sk;
3751 	struct socket *sock;
3752 	struct inet_sock *inetsk;
3753 	struct sctp_af *af;
3754 	int err = 0;
3755 
3756 	/* An association cannot be branched off from an already peeled-off
3757 	 * socket, nor is this supported for tcp style sockets.
3758 	 */
3759 	if (!sctp_style(sk, UDP))
3760 		return -EINVAL;
3761 
3762 	/* Create a new socket.  */
3763 	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
3764 	if (err < 0)
3765 		return err;
3766 
3767 	/* Populate the fields of the newsk from the oldsk and migrate the
3768 	 * asoc to the newsk.
3769 	 */
3770 	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
3771 
3772 	/* Make peeled-off sockets more like 1-1 accepted sockets.
3773 	 * Set the daddr and initialize id to something more random
3774 	 */
3775 	af = sctp_get_af_specific(asoc->peer.primary_addr.sa.sa_family);
3776 	af->to_sk_daddr(&asoc->peer.primary_addr, sk);
3777 	inetsk = inet_sk(sock->sk);
3778 	inetsk->id = asoc->next_tsn ^ jiffies;
3779 
3780 	*sockp = sock;
3781 
3782 	return err;
3783 }
3784 
3785 static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
3786 {
3787 	sctp_peeloff_arg_t peeloff;
3788 	struct socket *newsock;
3789 	int retval = 0;
3790 	struct sctp_association *asoc;
3791 
3792 	if (len < sizeof(sctp_peeloff_arg_t))
3793 		return -EINVAL;
3794 	len = sizeof(sctp_peeloff_arg_t);
3795 	if (copy_from_user(&peeloff, optval, len))
3796 		return -EFAULT;
3797 
3798 	asoc = sctp_id2assoc(sk, peeloff.associd);
3799 	if (!asoc) {
3800 		retval = -EINVAL;
3801 		goto out;
3802 	}
3803 
3804 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p\n", __FUNCTION__, sk, asoc);
3805 
3806 	retval = sctp_do_peeloff(asoc, &newsock);
3807 	if (retval < 0)
3808 		goto out;
3809 
3810 	/* Map the socket to an unused fd that can be returned to the user.  */
3811 	retval = sock_map_fd(newsock);
3812 	if (retval < 0) {
3813 		sock_release(newsock);
3814 		goto out;
3815 	}
3816 
3817 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p newsk: %p sd: %d\n",
3818 			  __FUNCTION__, sk, asoc, newsock->sk, retval);
3819 
3820 	/* Return the fd mapped to the new socket.  */
3821 	peeloff.sd = retval;
3822 	if (put_user(len, optlen))
3823 		return -EFAULT;
3824 	if (copy_to_user(optval, &peeloff, len))
3825 		retval = -EFAULT;
3826 
3827 out:
3828 	return retval;
3829 }
3830 
3831 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
3832  *
3833  * Applications can enable or disable heartbeats for any peer address of
3834  * an association, modify an address's heartbeat interval, force a
3835  * heartbeat to be sent immediately, and adjust the address's maximum
3836  * number of retransmissions sent before an address is considered
3837  * unreachable.  The following structure is used to access and modify an
3838  * address's parameters:
3839  *
3840  *  struct sctp_paddrparams {
3841  *     sctp_assoc_t            spp_assoc_id;
3842  *     struct sockaddr_storage spp_address;
3843  *     uint32_t                spp_hbinterval;
3844  *     uint16_t                spp_pathmaxrxt;
3845  *     uint32_t                spp_pathmtu;
3846  *     uint32_t                spp_sackdelay;
3847  *     uint32_t                spp_flags;
3848  * };
3849  *
3850  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
3851  *                     application, and identifies the association for
3852  *                     this query.
3853  *   spp_address     - This specifies which address is of interest.
3854  *   spp_hbinterval  - This contains the value of the heartbeat interval,
3855  *                     in milliseconds.  If a  value of zero
3856  *                     is present in this field then no changes are to
3857  *                     be made to this parameter.
3858  *   spp_pathmaxrxt  - This contains the maximum number of
3859  *                     retransmissions before this address shall be
3860  *                     considered unreachable. If a  value of zero
3861  *                     is present in this field then no changes are to
3862  *                     be made to this parameter.
3863  *   spp_pathmtu     - When Path MTU discovery is disabled the value
3864  *                     specified here will be the "fixed" path mtu.
3865  *                     Note that if the spp_address field is empty
3866  *                     then all associations on this address will
3867  *                     have this fixed path mtu set upon them.
3868  *
3869  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
3870  *                     the number of milliseconds that sacks will be delayed
3871  *                     for. This value will apply to all addresses of an
3872  *                     association if the spp_address field is empty. Note
3873  *                     also, that if delayed sack is enabled and this
3874  *                     value is set to 0, no change is made to the last
3875  *                     recorded delayed sack timer value.
3876  *
3877  *   spp_flags       - These flags are used to control various features
3878  *                     on an association. The flag field may contain
3879  *                     zero or more of the following options.
3880  *
3881  *                     SPP_HB_ENABLE  - Enable heartbeats on the
3882  *                     specified address. Note that if the address
3883  *                     field is empty all addresses for the association
3884  *                     have heartbeats enabled upon them.
3885  *
3886  *                     SPP_HB_DISABLE - Disable heartbeats on the
3887  *                     speicifed address. Note that if the address
3888  *                     field is empty all addresses for the association
3889  *                     will have their heartbeats disabled. Note also
3890  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
3891  *                     mutually exclusive, only one of these two should
3892  *                     be specified. Enabling both fields will have
3893  *                     undetermined results.
3894  *
3895  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
3896  *                     to be made immediately.
3897  *
3898  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
3899  *                     discovery upon the specified address. Note that
3900  *                     if the address feild is empty then all addresses
3901  *                     on the association are effected.
3902  *
3903  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
3904  *                     discovery upon the specified address. Note that
3905  *                     if the address feild is empty then all addresses
3906  *                     on the association are effected. Not also that
3907  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
3908  *                     exclusive. Enabling both will have undetermined
3909  *                     results.
3910  *
3911  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
3912  *                     on delayed sack. The time specified in spp_sackdelay
3913  *                     is used to specify the sack delay for this address. Note
3914  *                     that if spp_address is empty then all addresses will
3915  *                     enable delayed sack and take on the sack delay
3916  *                     value specified in spp_sackdelay.
3917  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
3918  *                     off delayed sack. If the spp_address field is blank then
3919  *                     delayed sack is disabled for the entire association. Note
3920  *                     also that this field is mutually exclusive to
3921  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
3922  *                     results.
3923  */
3924 static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
3925 					    char __user *optval, int __user *optlen)
3926 {
3927 	struct sctp_paddrparams  params;
3928 	struct sctp_transport   *trans = NULL;
3929 	struct sctp_association *asoc = NULL;
3930 	struct sctp_sock        *sp = sctp_sk(sk);
3931 
3932 	if (len < sizeof(struct sctp_paddrparams))
3933 		return -EINVAL;
3934 	len = sizeof(struct sctp_paddrparams);
3935 	if (copy_from_user(&params, optval, len))
3936 		return -EFAULT;
3937 
3938 	/* If an address other than INADDR_ANY is specified, and
3939 	 * no transport is found, then the request is invalid.
3940 	 */
3941 	if (!sctp_is_any(( union sctp_addr *)&params.spp_address)) {
3942 		trans = sctp_addr_id2transport(sk, &params.spp_address,
3943 					       params.spp_assoc_id);
3944 		if (!trans) {
3945 			SCTP_DEBUG_PRINTK("Failed no transport\n");
3946 			return -EINVAL;
3947 		}
3948 	}
3949 
3950 	/* Get association, if assoc_id != 0 and the socket is a one
3951 	 * to many style socket, and an association was not found, then
3952 	 * the id was invalid.
3953 	 */
3954 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
3955 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
3956 		SCTP_DEBUG_PRINTK("Failed no association\n");
3957 		return -EINVAL;
3958 	}
3959 
3960 	if (trans) {
3961 		/* Fetch transport values. */
3962 		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
3963 		params.spp_pathmtu    = trans->pathmtu;
3964 		params.spp_pathmaxrxt = trans->pathmaxrxt;
3965 		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
3966 
3967 		/*draft-11 doesn't say what to return in spp_flags*/
3968 		params.spp_flags      = trans->param_flags;
3969 	} else if (asoc) {
3970 		/* Fetch association values. */
3971 		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
3972 		params.spp_pathmtu    = asoc->pathmtu;
3973 		params.spp_pathmaxrxt = asoc->pathmaxrxt;
3974 		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
3975 
3976 		/*draft-11 doesn't say what to return in spp_flags*/
3977 		params.spp_flags      = asoc->param_flags;
3978 	} else {
3979 		/* Fetch socket values. */
3980 		params.spp_hbinterval = sp->hbinterval;
3981 		params.spp_pathmtu    = sp->pathmtu;
3982 		params.spp_sackdelay  = sp->sackdelay;
3983 		params.spp_pathmaxrxt = sp->pathmaxrxt;
3984 
3985 		/*draft-11 doesn't say what to return in spp_flags*/
3986 		params.spp_flags      = sp->param_flags;
3987 	}
3988 
3989 	if (copy_to_user(optval, &params, len))
3990 		return -EFAULT;
3991 
3992 	if (put_user(len, optlen))
3993 		return -EFAULT;
3994 
3995 	return 0;
3996 }
3997 
3998 /* 7.1.23. Delayed Ack Timer (SCTP_DELAYED_ACK_TIME)
3999  *
4000  *   This options will get or set the delayed ack timer.  The time is set
4001  *   in milliseconds.  If the assoc_id is 0, then this sets or gets the
4002  *   endpoints default delayed ack timer value.  If the assoc_id field is
4003  *   non-zero, then the set or get effects the specified association.
4004  *
4005  *   struct sctp_assoc_value {
4006  *       sctp_assoc_t            assoc_id;
4007  *       uint32_t                assoc_value;
4008  *   };
4009  *
4010  *     assoc_id    - This parameter, indicates which association the
4011  *                   user is preforming an action upon. Note that if
4012  *                   this field's value is zero then the endpoints
4013  *                   default value is changed (effecting future
4014  *                   associations only).
4015  *
4016  *     assoc_value - This parameter contains the number of milliseconds
4017  *                   that the user is requesting the delayed ACK timer
4018  *                   be set to. Note that this value is defined in
4019  *                   the standard to be between 200 and 500 milliseconds.
4020  *
4021  *                   Note: a value of zero will leave the value alone,
4022  *                   but disable SACK delay. A non-zero value will also
4023  *                   enable SACK delay.
4024  */
4025 static int sctp_getsockopt_delayed_ack_time(struct sock *sk, int len,
4026 					    char __user *optval,
4027 					    int __user *optlen)
4028 {
4029 	struct sctp_assoc_value  params;
4030 	struct sctp_association *asoc = NULL;
4031 	struct sctp_sock        *sp = sctp_sk(sk);
4032 
4033 	if (len < sizeof(struct sctp_assoc_value))
4034 		return - EINVAL;
4035 
4036 	len = sizeof(struct sctp_assoc_value);
4037 
4038 	if (copy_from_user(&params, optval, len))
4039 		return -EFAULT;
4040 
4041 	/* Get association, if assoc_id != 0 and the socket is a one
4042 	 * to many style socket, and an association was not found, then
4043 	 * the id was invalid.
4044 	 */
4045 	asoc = sctp_id2assoc(sk, params.assoc_id);
4046 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
4047 		return -EINVAL;
4048 
4049 	if (asoc) {
4050 		/* Fetch association values. */
4051 		if (asoc->param_flags & SPP_SACKDELAY_ENABLE)
4052 			params.assoc_value = jiffies_to_msecs(
4053 				asoc->sackdelay);
4054 		else
4055 			params.assoc_value = 0;
4056 	} else {
4057 		/* Fetch socket values. */
4058 		if (sp->param_flags & SPP_SACKDELAY_ENABLE)
4059 			params.assoc_value  = sp->sackdelay;
4060 		else
4061 			params.assoc_value  = 0;
4062 	}
4063 
4064 	if (copy_to_user(optval, &params, len))
4065 		return -EFAULT;
4066 
4067 	if (put_user(len, optlen))
4068 		return -EFAULT;
4069 
4070 	return 0;
4071 }
4072 
4073 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
4074  *
4075  * Applications can specify protocol parameters for the default association
4076  * initialization.  The option name argument to setsockopt() and getsockopt()
4077  * is SCTP_INITMSG.
4078  *
4079  * Setting initialization parameters is effective only on an unconnected
4080  * socket (for UDP-style sockets only future associations are effected
4081  * by the change).  With TCP-style sockets, this option is inherited by
4082  * sockets derived from a listener socket.
4083  */
4084 static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
4085 {
4086 	if (len < sizeof(struct sctp_initmsg))
4087 		return -EINVAL;
4088 	len = sizeof(struct sctp_initmsg);
4089 	if (put_user(len, optlen))
4090 		return -EFAULT;
4091 	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
4092 		return -EFAULT;
4093 	return 0;
4094 }
4095 
4096 static int sctp_getsockopt_peer_addrs_num_old(struct sock *sk, int len,
4097 					      char __user *optval,
4098 					      int __user *optlen)
4099 {
4100 	sctp_assoc_t id;
4101 	struct sctp_association *asoc;
4102 	struct list_head *pos;
4103 	int cnt = 0;
4104 
4105 	if (len < sizeof(sctp_assoc_t))
4106 		return -EINVAL;
4107 
4108 	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
4109 		return -EFAULT;
4110 
4111 	/* For UDP-style sockets, id specifies the association to query.  */
4112 	asoc = sctp_id2assoc(sk, id);
4113 	if (!asoc)
4114 		return -EINVAL;
4115 
4116 	list_for_each(pos, &asoc->peer.transport_addr_list) {
4117 		cnt ++;
4118 	}
4119 
4120 	return cnt;
4121 }
4122 
4123 /*
4124  * Old API for getting list of peer addresses. Does not work for 32-bit
4125  * programs running on a 64-bit kernel
4126  */
4127 static int sctp_getsockopt_peer_addrs_old(struct sock *sk, int len,
4128 					  char __user *optval,
4129 					  int __user *optlen)
4130 {
4131 	struct sctp_association *asoc;
4132 	struct list_head *pos;
4133 	int cnt = 0;
4134 	struct sctp_getaddrs_old getaddrs;
4135 	struct sctp_transport *from;
4136 	void __user *to;
4137 	union sctp_addr temp;
4138 	struct sctp_sock *sp = sctp_sk(sk);
4139 	int addrlen;
4140 
4141 	if (len < sizeof(struct sctp_getaddrs_old))
4142 		return -EINVAL;
4143 
4144 	len = sizeof(struct sctp_getaddrs_old);
4145 
4146 	if (copy_from_user(&getaddrs, optval, len))
4147 		return -EFAULT;
4148 
4149 	if (getaddrs.addr_num <= 0) return -EINVAL;
4150 
4151 	/* For UDP-style sockets, id specifies the association to query.  */
4152 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4153 	if (!asoc)
4154 		return -EINVAL;
4155 
4156 	to = (void __user *)getaddrs.addrs;
4157 	list_for_each(pos, &asoc->peer.transport_addr_list) {
4158 		from = list_entry(pos, struct sctp_transport, transports);
4159 		memcpy(&temp, &from->ipaddr, sizeof(temp));
4160 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4161 		addrlen = sctp_get_af_specific(sk->sk_family)->sockaddr_len;
4162 		if (copy_to_user(to, &temp, addrlen))
4163 			return -EFAULT;
4164 		to += addrlen ;
4165 		cnt ++;
4166 		if (cnt >= getaddrs.addr_num) break;
4167 	}
4168 	getaddrs.addr_num = cnt;
4169 	if (put_user(len, optlen))
4170 		return -EFAULT;
4171 	if (copy_to_user(optval, &getaddrs, len))
4172 		return -EFAULT;
4173 
4174 	return 0;
4175 }
4176 
4177 static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
4178 				      char __user *optval, int __user *optlen)
4179 {
4180 	struct sctp_association *asoc;
4181 	struct list_head *pos;
4182 	int cnt = 0;
4183 	struct sctp_getaddrs getaddrs;
4184 	struct sctp_transport *from;
4185 	void __user *to;
4186 	union sctp_addr temp;
4187 	struct sctp_sock *sp = sctp_sk(sk);
4188 	int addrlen;
4189 	size_t space_left;
4190 	int bytes_copied;
4191 
4192 	if (len < sizeof(struct sctp_getaddrs))
4193 		return -EINVAL;
4194 
4195 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4196 		return -EFAULT;
4197 
4198 	/* For UDP-style sockets, id specifies the association to query.  */
4199 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4200 	if (!asoc)
4201 		return -EINVAL;
4202 
4203 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4204 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4205 
4206 	list_for_each(pos, &asoc->peer.transport_addr_list) {
4207 		from = list_entry(pos, struct sctp_transport, transports);
4208 		memcpy(&temp, &from->ipaddr, sizeof(temp));
4209 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4210 		addrlen = sctp_get_af_specific(sk->sk_family)->sockaddr_len;
4211 		if (space_left < addrlen)
4212 			return -ENOMEM;
4213 		if (copy_to_user(to, &temp, addrlen))
4214 			return -EFAULT;
4215 		to += addrlen;
4216 		cnt++;
4217 		space_left -= addrlen;
4218 	}
4219 
4220 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
4221 		return -EFAULT;
4222 	bytes_copied = ((char __user *)to) - optval;
4223 	if (put_user(bytes_copied, optlen))
4224 		return -EFAULT;
4225 
4226 	return 0;
4227 }
4228 
4229 static int sctp_getsockopt_local_addrs_num_old(struct sock *sk, int len,
4230 					       char __user *optval,
4231 					       int __user *optlen)
4232 {
4233 	sctp_assoc_t id;
4234 	struct sctp_bind_addr *bp;
4235 	struct sctp_association *asoc;
4236 	struct sctp_sockaddr_entry *addr;
4237 	int cnt = 0;
4238 
4239 	if (len < sizeof(sctp_assoc_t))
4240 		return -EINVAL;
4241 
4242 	if (copy_from_user(&id, optval, sizeof(sctp_assoc_t)))
4243 		return -EFAULT;
4244 
4245 	/*
4246 	 *  For UDP-style sockets, id specifies the association to query.
4247 	 *  If the id field is set to the value '0' then the locally bound
4248 	 *  addresses are returned without regard to any particular
4249 	 *  association.
4250 	 */
4251 	if (0 == id) {
4252 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4253 	} else {
4254 		asoc = sctp_id2assoc(sk, id);
4255 		if (!asoc)
4256 			return -EINVAL;
4257 		bp = &asoc->base.bind_addr;
4258 	}
4259 
4260 	/* If the endpoint is bound to 0.0.0.0 or ::0, count the valid
4261 	 * addresses from the global local address list.
4262 	 */
4263 	if (sctp_list_single_entry(&bp->address_list)) {
4264 		addr = list_entry(bp->address_list.next,
4265 				  struct sctp_sockaddr_entry, list);
4266 		if (sctp_is_any(&addr->a)) {
4267 			rcu_read_lock();
4268 			list_for_each_entry_rcu(addr,
4269 						&sctp_local_addr_list, list) {
4270 				if (!addr->valid)
4271 					continue;
4272 
4273 				if ((PF_INET == sk->sk_family) &&
4274 				    (AF_INET6 == addr->a.sa.sa_family))
4275 					continue;
4276 
4277 				cnt++;
4278 			}
4279 			rcu_read_unlock();
4280 		} else {
4281 			cnt = 1;
4282 		}
4283 		goto done;
4284 	}
4285 
4286 	/* Protection on the bound address list is not needed,
4287 	 * since in the socket option context we hold the socket lock,
4288 	 * so there is no way that the bound address list can change.
4289 	 */
4290 	list_for_each_entry(addr, &bp->address_list, list) {
4291 		cnt ++;
4292 	}
4293 done:
4294 	return cnt;
4295 }
4296 
4297 /* Helper function that copies local addresses to user and returns the number
4298  * of addresses copied.
4299  */
4300 static int sctp_copy_laddrs_old(struct sock *sk, __u16 port,
4301 					int max_addrs, void *to,
4302 					int *bytes_copied)
4303 {
4304 	struct sctp_sockaddr_entry *addr;
4305 	union sctp_addr temp;
4306 	int cnt = 0;
4307 	int addrlen;
4308 
4309 	rcu_read_lock();
4310 	list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
4311 		if (!addr->valid)
4312 			continue;
4313 
4314 		if ((PF_INET == sk->sk_family) &&
4315 		    (AF_INET6 == addr->a.sa.sa_family))
4316 			continue;
4317 		memcpy(&temp, &addr->a, sizeof(temp));
4318 		if (!temp.v4.sin_port)
4319 			temp.v4.sin_port = htons(port);
4320 
4321 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4322 								&temp);
4323 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4324 		memcpy(to, &temp, addrlen);
4325 
4326 		to += addrlen;
4327 		*bytes_copied += addrlen;
4328 		cnt ++;
4329 		if (cnt >= max_addrs) break;
4330 	}
4331 	rcu_read_unlock();
4332 
4333 	return cnt;
4334 }
4335 
4336 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
4337 			    size_t space_left, int *bytes_copied)
4338 {
4339 	struct sctp_sockaddr_entry *addr;
4340 	union sctp_addr temp;
4341 	int cnt = 0;
4342 	int addrlen;
4343 
4344 	rcu_read_lock();
4345 	list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
4346 		if (!addr->valid)
4347 			continue;
4348 
4349 		if ((PF_INET == sk->sk_family) &&
4350 		    (AF_INET6 == addr->a.sa.sa_family))
4351 			continue;
4352 		memcpy(&temp, &addr->a, sizeof(temp));
4353 		if (!temp.v4.sin_port)
4354 			temp.v4.sin_port = htons(port);
4355 
4356 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4357 								&temp);
4358 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4359 		if (space_left < addrlen) {
4360 			cnt =  -ENOMEM;
4361 			break;
4362 		}
4363 		memcpy(to, &temp, addrlen);
4364 
4365 		to += addrlen;
4366 		cnt ++;
4367 		space_left -= addrlen;
4368 		*bytes_copied += addrlen;
4369 	}
4370 	rcu_read_unlock();
4371 
4372 	return cnt;
4373 }
4374 
4375 /* Old API for getting list of local addresses. Does not work for 32-bit
4376  * programs running on a 64-bit kernel
4377  */
4378 static int sctp_getsockopt_local_addrs_old(struct sock *sk, int len,
4379 					   char __user *optval, int __user *optlen)
4380 {
4381 	struct sctp_bind_addr *bp;
4382 	struct sctp_association *asoc;
4383 	int cnt = 0;
4384 	struct sctp_getaddrs_old getaddrs;
4385 	struct sctp_sockaddr_entry *addr;
4386 	void __user *to;
4387 	union sctp_addr temp;
4388 	struct sctp_sock *sp = sctp_sk(sk);
4389 	int addrlen;
4390 	int err = 0;
4391 	void *addrs;
4392 	void *buf;
4393 	int bytes_copied = 0;
4394 
4395 	if (len < sizeof(struct sctp_getaddrs_old))
4396 		return -EINVAL;
4397 
4398 	len = sizeof(struct sctp_getaddrs_old);
4399 	if (copy_from_user(&getaddrs, optval, len))
4400 		return -EFAULT;
4401 
4402 	if (getaddrs.addr_num <= 0) return -EINVAL;
4403 	/*
4404 	 *  For UDP-style sockets, id specifies the association to query.
4405 	 *  If the id field is set to the value '0' then the locally bound
4406 	 *  addresses are returned without regard to any particular
4407 	 *  association.
4408 	 */
4409 	if (0 == getaddrs.assoc_id) {
4410 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4411 	} else {
4412 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4413 		if (!asoc)
4414 			return -EINVAL;
4415 		bp = &asoc->base.bind_addr;
4416 	}
4417 
4418 	to = getaddrs.addrs;
4419 
4420 	/* Allocate space for a local instance of packed array to hold all
4421 	 * the data.  We store addresses here first and then put write them
4422 	 * to the user in one shot.
4423 	 */
4424 	addrs = kmalloc(sizeof(union sctp_addr) * getaddrs.addr_num,
4425 			GFP_KERNEL);
4426 	if (!addrs)
4427 		return -ENOMEM;
4428 
4429 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4430 	 * addresses from the global local address list.
4431 	 */
4432 	if (sctp_list_single_entry(&bp->address_list)) {
4433 		addr = list_entry(bp->address_list.next,
4434 				  struct sctp_sockaddr_entry, list);
4435 		if (sctp_is_any(&addr->a)) {
4436 			cnt = sctp_copy_laddrs_old(sk, bp->port,
4437 						   getaddrs.addr_num,
4438 						   addrs, &bytes_copied);
4439 			goto copy_getaddrs;
4440 		}
4441 	}
4442 
4443 	buf = addrs;
4444 	/* Protection on the bound address list is not needed since
4445 	 * in the socket option context we hold a socket lock and
4446 	 * thus the bound address list can't change.
4447 	 */
4448 	list_for_each_entry(addr, &bp->address_list, list) {
4449 		memcpy(&temp, &addr->a, sizeof(temp));
4450 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4451 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4452 		memcpy(buf, &temp, addrlen);
4453 		buf += addrlen;
4454 		bytes_copied += addrlen;
4455 		cnt ++;
4456 		if (cnt >= getaddrs.addr_num) break;
4457 	}
4458 
4459 copy_getaddrs:
4460 	/* copy the entire address list into the user provided space */
4461 	if (copy_to_user(to, addrs, bytes_copied)) {
4462 		err = -EFAULT;
4463 		goto error;
4464 	}
4465 
4466 	/* copy the leading structure back to user */
4467 	getaddrs.addr_num = cnt;
4468 	if (copy_to_user(optval, &getaddrs, len))
4469 		err = -EFAULT;
4470 
4471 error:
4472 	kfree(addrs);
4473 	return err;
4474 }
4475 
4476 static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
4477 				       char __user *optval, int __user *optlen)
4478 {
4479 	struct sctp_bind_addr *bp;
4480 	struct sctp_association *asoc;
4481 	int cnt = 0;
4482 	struct sctp_getaddrs getaddrs;
4483 	struct sctp_sockaddr_entry *addr;
4484 	void __user *to;
4485 	union sctp_addr temp;
4486 	struct sctp_sock *sp = sctp_sk(sk);
4487 	int addrlen;
4488 	int err = 0;
4489 	size_t space_left;
4490 	int bytes_copied = 0;
4491 	void *addrs;
4492 	void *buf;
4493 
4494 	if (len < sizeof(struct sctp_getaddrs))
4495 		return -EINVAL;
4496 
4497 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4498 		return -EFAULT;
4499 
4500 	/*
4501 	 *  For UDP-style sockets, id specifies the association to query.
4502 	 *  If the id field is set to the value '0' then the locally bound
4503 	 *  addresses are returned without regard to any particular
4504 	 *  association.
4505 	 */
4506 	if (0 == getaddrs.assoc_id) {
4507 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4508 	} else {
4509 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4510 		if (!asoc)
4511 			return -EINVAL;
4512 		bp = &asoc->base.bind_addr;
4513 	}
4514 
4515 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4516 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4517 
4518 	addrs = kmalloc(space_left, GFP_KERNEL);
4519 	if (!addrs)
4520 		return -ENOMEM;
4521 
4522 	/* If the endpoint is bound to 0.0.0.0 or ::0, get 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(&addr->a)) {
4529 			cnt = sctp_copy_laddrs(sk, bp->port, addrs,
4530 						space_left, &bytes_copied);
4531 			if (cnt < 0) {
4532 				err = cnt;
4533 				goto out;
4534 			}
4535 			goto copy_getaddrs;
4536 		}
4537 	}
4538 
4539 	buf = addrs;
4540 	/* Protection on the bound address list is not needed since
4541 	 * in the socket option context we hold a socket lock and
4542 	 * thus the bound address list can't change.
4543 	 */
4544 	list_for_each_entry(addr, &bp->address_list, list) {
4545 		memcpy(&temp, &addr->a, sizeof(temp));
4546 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4547 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4548 		if (space_left < addrlen) {
4549 			err =  -ENOMEM; /*fixme: right error?*/
4550 			goto out;
4551 		}
4552 		memcpy(buf, &temp, addrlen);
4553 		buf += addrlen;
4554 		bytes_copied += addrlen;
4555 		cnt ++;
4556 		space_left -= addrlen;
4557 	}
4558 
4559 copy_getaddrs:
4560 	if (copy_to_user(to, addrs, bytes_copied)) {
4561 		err = -EFAULT;
4562 		goto out;
4563 	}
4564 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num)) {
4565 		err = -EFAULT;
4566 		goto out;
4567 	}
4568 	if (put_user(bytes_copied, optlen))
4569 		err = -EFAULT;
4570 out:
4571 	kfree(addrs);
4572 	return err;
4573 }
4574 
4575 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
4576  *
4577  * Requests that the local SCTP stack use the enclosed peer address as
4578  * the association primary.  The enclosed address must be one of the
4579  * association peer's addresses.
4580  */
4581 static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
4582 					char __user *optval, int __user *optlen)
4583 {
4584 	struct sctp_prim prim;
4585 	struct sctp_association *asoc;
4586 	struct sctp_sock *sp = sctp_sk(sk);
4587 
4588 	if (len < sizeof(struct sctp_prim))
4589 		return -EINVAL;
4590 
4591 	len = sizeof(struct sctp_prim);
4592 
4593 	if (copy_from_user(&prim, optval, len))
4594 		return -EFAULT;
4595 
4596 	asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
4597 	if (!asoc)
4598 		return -EINVAL;
4599 
4600 	if (!asoc->peer.primary_path)
4601 		return -ENOTCONN;
4602 
4603 	memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
4604 		asoc->peer.primary_path->af_specific->sockaddr_len);
4605 
4606 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp,
4607 			(union sctp_addr *)&prim.ssp_addr);
4608 
4609 	if (put_user(len, optlen))
4610 		return -EFAULT;
4611 	if (copy_to_user(optval, &prim, len))
4612 		return -EFAULT;
4613 
4614 	return 0;
4615 }
4616 
4617 /*
4618  * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
4619  *
4620  * Requests that the local endpoint set the specified Adaptation Layer
4621  * Indication parameter for all future INIT and INIT-ACK exchanges.
4622  */
4623 static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
4624 				  char __user *optval, int __user *optlen)
4625 {
4626 	struct sctp_setadaptation adaptation;
4627 
4628 	if (len < sizeof(struct sctp_setadaptation))
4629 		return -EINVAL;
4630 
4631 	len = sizeof(struct sctp_setadaptation);
4632 
4633 	adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
4634 
4635 	if (put_user(len, optlen))
4636 		return -EFAULT;
4637 	if (copy_to_user(optval, &adaptation, len))
4638 		return -EFAULT;
4639 
4640 	return 0;
4641 }
4642 
4643 /*
4644  *
4645  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
4646  *
4647  *   Applications that wish to use the sendto() system call may wish to
4648  *   specify a default set of parameters that would normally be supplied
4649  *   through the inclusion of ancillary data.  This socket option allows
4650  *   such an application to set the default sctp_sndrcvinfo structure.
4651 
4652 
4653  *   The application that wishes to use this socket option simply passes
4654  *   in to this call the sctp_sndrcvinfo structure defined in Section
4655  *   5.2.2) The input parameters accepted by this call include
4656  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
4657  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
4658  *   to this call if the caller is using the UDP model.
4659  *
4660  *   For getsockopt, it get the default sctp_sndrcvinfo structure.
4661  */
4662 static int sctp_getsockopt_default_send_param(struct sock *sk,
4663 					int len, char __user *optval,
4664 					int __user *optlen)
4665 {
4666 	struct sctp_sndrcvinfo info;
4667 	struct sctp_association *asoc;
4668 	struct sctp_sock *sp = sctp_sk(sk);
4669 
4670 	if (len < sizeof(struct sctp_sndrcvinfo))
4671 		return -EINVAL;
4672 
4673 	len = sizeof(struct sctp_sndrcvinfo);
4674 
4675 	if (copy_from_user(&info, optval, len))
4676 		return -EFAULT;
4677 
4678 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
4679 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
4680 		return -EINVAL;
4681 
4682 	if (asoc) {
4683 		info.sinfo_stream = asoc->default_stream;
4684 		info.sinfo_flags = asoc->default_flags;
4685 		info.sinfo_ppid = asoc->default_ppid;
4686 		info.sinfo_context = asoc->default_context;
4687 		info.sinfo_timetolive = asoc->default_timetolive;
4688 	} else {
4689 		info.sinfo_stream = sp->default_stream;
4690 		info.sinfo_flags = sp->default_flags;
4691 		info.sinfo_ppid = sp->default_ppid;
4692 		info.sinfo_context = sp->default_context;
4693 		info.sinfo_timetolive = sp->default_timetolive;
4694 	}
4695 
4696 	if (put_user(len, optlen))
4697 		return -EFAULT;
4698 	if (copy_to_user(optval, &info, len))
4699 		return -EFAULT;
4700 
4701 	return 0;
4702 }
4703 
4704 /*
4705  *
4706  * 7.1.5 SCTP_NODELAY
4707  *
4708  * Turn on/off any Nagle-like algorithm.  This means that packets are
4709  * generally sent as soon as possible and no unnecessary delays are
4710  * introduced, at the cost of more packets in the network.  Expects an
4711  * integer boolean flag.
4712  */
4713 
4714 static int sctp_getsockopt_nodelay(struct sock *sk, int len,
4715 				   char __user *optval, int __user *optlen)
4716 {
4717 	int val;
4718 
4719 	if (len < sizeof(int))
4720 		return -EINVAL;
4721 
4722 	len = sizeof(int);
4723 	val = (sctp_sk(sk)->nodelay == 1);
4724 	if (put_user(len, optlen))
4725 		return -EFAULT;
4726 	if (copy_to_user(optval, &val, len))
4727 		return -EFAULT;
4728 	return 0;
4729 }
4730 
4731 /*
4732  *
4733  * 7.1.1 SCTP_RTOINFO
4734  *
4735  * The protocol parameters used to initialize and bound retransmission
4736  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
4737  * and modify these parameters.
4738  * All parameters are time values, in milliseconds.  A value of 0, when
4739  * modifying the parameters, indicates that the current value should not
4740  * be changed.
4741  *
4742  */
4743 static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
4744 				char __user *optval,
4745 				int __user *optlen) {
4746 	struct sctp_rtoinfo rtoinfo;
4747 	struct sctp_association *asoc;
4748 
4749 	if (len < sizeof (struct sctp_rtoinfo))
4750 		return -EINVAL;
4751 
4752 	len = sizeof(struct sctp_rtoinfo);
4753 
4754 	if (copy_from_user(&rtoinfo, optval, len))
4755 		return -EFAULT;
4756 
4757 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
4758 
4759 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
4760 		return -EINVAL;
4761 
4762 	/* Values corresponding to the specific association. */
4763 	if (asoc) {
4764 		rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
4765 		rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
4766 		rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
4767 	} else {
4768 		/* Values corresponding to the endpoint. */
4769 		struct sctp_sock *sp = sctp_sk(sk);
4770 
4771 		rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
4772 		rtoinfo.srto_max = sp->rtoinfo.srto_max;
4773 		rtoinfo.srto_min = sp->rtoinfo.srto_min;
4774 	}
4775 
4776 	if (put_user(len, optlen))
4777 		return -EFAULT;
4778 
4779 	if (copy_to_user(optval, &rtoinfo, len))
4780 		return -EFAULT;
4781 
4782 	return 0;
4783 }
4784 
4785 /*
4786  *
4787  * 7.1.2 SCTP_ASSOCINFO
4788  *
4789  * This option is used to tune the maximum retransmission attempts
4790  * of the association.
4791  * Returns an error if the new association retransmission value is
4792  * greater than the sum of the retransmission value  of the peer.
4793  * See [SCTP] for more information.
4794  *
4795  */
4796 static int sctp_getsockopt_associnfo(struct sock *sk, int len,
4797 				     char __user *optval,
4798 				     int __user *optlen)
4799 {
4800 
4801 	struct sctp_assocparams assocparams;
4802 	struct sctp_association *asoc;
4803 	struct list_head *pos;
4804 	int cnt = 0;
4805 
4806 	if (len < sizeof (struct sctp_assocparams))
4807 		return -EINVAL;
4808 
4809 	len = sizeof(struct sctp_assocparams);
4810 
4811 	if (copy_from_user(&assocparams, optval, len))
4812 		return -EFAULT;
4813 
4814 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
4815 
4816 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
4817 		return -EINVAL;
4818 
4819 	/* Values correspoinding to the specific association */
4820 	if (asoc) {
4821 		assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
4822 		assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
4823 		assocparams.sasoc_local_rwnd = asoc->a_rwnd;
4824 		assocparams.sasoc_cookie_life = (asoc->cookie_life.tv_sec
4825 						* 1000) +
4826 						(asoc->cookie_life.tv_usec
4827 						/ 1000);
4828 
4829 		list_for_each(pos, &asoc->peer.transport_addr_list) {
4830 			cnt ++;
4831 		}
4832 
4833 		assocparams.sasoc_number_peer_destinations = cnt;
4834 	} else {
4835 		/* Values corresponding to the endpoint */
4836 		struct sctp_sock *sp = sctp_sk(sk);
4837 
4838 		assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
4839 		assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
4840 		assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
4841 		assocparams.sasoc_cookie_life =
4842 					sp->assocparams.sasoc_cookie_life;
4843 		assocparams.sasoc_number_peer_destinations =
4844 					sp->assocparams.
4845 					sasoc_number_peer_destinations;
4846 	}
4847 
4848 	if (put_user(len, optlen))
4849 		return -EFAULT;
4850 
4851 	if (copy_to_user(optval, &assocparams, len))
4852 		return -EFAULT;
4853 
4854 	return 0;
4855 }
4856 
4857 /*
4858  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
4859  *
4860  * This socket option is a boolean flag which turns on or off mapped V4
4861  * addresses.  If this option is turned on and the socket is type
4862  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
4863  * If this option is turned off, then no mapping will be done of V4
4864  * addresses and a user will receive both PF_INET6 and PF_INET type
4865  * addresses on the socket.
4866  */
4867 static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
4868 				    char __user *optval, int __user *optlen)
4869 {
4870 	int val;
4871 	struct sctp_sock *sp = sctp_sk(sk);
4872 
4873 	if (len < sizeof(int))
4874 		return -EINVAL;
4875 
4876 	len = sizeof(int);
4877 	val = sp->v4mapped;
4878 	if (put_user(len, optlen))
4879 		return -EFAULT;
4880 	if (copy_to_user(optval, &val, len))
4881 		return -EFAULT;
4882 
4883 	return 0;
4884 }
4885 
4886 /*
4887  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
4888  * (chapter and verse is quoted at sctp_setsockopt_context())
4889  */
4890 static int sctp_getsockopt_context(struct sock *sk, int len,
4891 				   char __user *optval, int __user *optlen)
4892 {
4893 	struct sctp_assoc_value params;
4894 	struct sctp_sock *sp;
4895 	struct sctp_association *asoc;
4896 
4897 	if (len < sizeof(struct sctp_assoc_value))
4898 		return -EINVAL;
4899 
4900 	len = sizeof(struct sctp_assoc_value);
4901 
4902 	if (copy_from_user(&params, optval, len))
4903 		return -EFAULT;
4904 
4905 	sp = sctp_sk(sk);
4906 
4907 	if (params.assoc_id != 0) {
4908 		asoc = sctp_id2assoc(sk, params.assoc_id);
4909 		if (!asoc)
4910 			return -EINVAL;
4911 		params.assoc_value = asoc->default_rcv_context;
4912 	} else {
4913 		params.assoc_value = sp->default_rcv_context;
4914 	}
4915 
4916 	if (put_user(len, optlen))
4917 		return -EFAULT;
4918 	if (copy_to_user(optval, &params, len))
4919 		return -EFAULT;
4920 
4921 	return 0;
4922 }
4923 
4924 /*
4925  * 7.1.17 Set the maximum fragrmentation size (SCTP_MAXSEG)
4926  *
4927  * This socket option specifies the maximum size to put in any outgoing
4928  * SCTP chunk.  If a message is larger than this size it will be
4929  * fragmented by SCTP into the specified size.  Note that the underlying
4930  * SCTP implementation may fragment into smaller sized chunks when the
4931  * PMTU of the underlying association is smaller than the value set by
4932  * the user.
4933  */
4934 static int sctp_getsockopt_maxseg(struct sock *sk, int len,
4935 				  char __user *optval, int __user *optlen)
4936 {
4937 	int val;
4938 
4939 	if (len < sizeof(int))
4940 		return -EINVAL;
4941 
4942 	len = sizeof(int);
4943 
4944 	val = sctp_sk(sk)->user_frag;
4945 	if (put_user(len, optlen))
4946 		return -EFAULT;
4947 	if (copy_to_user(optval, &val, len))
4948 		return -EFAULT;
4949 
4950 	return 0;
4951 }
4952 
4953 /*
4954  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
4955  * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
4956  */
4957 static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
4958 					       char __user *optval, int __user *optlen)
4959 {
4960 	int val;
4961 
4962 	if (len < sizeof(int))
4963 		return -EINVAL;
4964 
4965 	len = sizeof(int);
4966 
4967 	val = sctp_sk(sk)->frag_interleave;
4968 	if (put_user(len, optlen))
4969 		return -EFAULT;
4970 	if (copy_to_user(optval, &val, len))
4971 		return -EFAULT;
4972 
4973 	return 0;
4974 }
4975 
4976 /*
4977  * 7.1.25.  Set or Get the sctp partial delivery point
4978  * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
4979  */
4980 static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
4981 						  char __user *optval,
4982 						  int __user *optlen)
4983 {
4984 	u32 val;
4985 
4986 	if (len < sizeof(u32))
4987 		return -EINVAL;
4988 
4989 	len = sizeof(u32);
4990 
4991 	val = sctp_sk(sk)->pd_point;
4992 	if (put_user(len, optlen))
4993 		return -EFAULT;
4994 	if (copy_to_user(optval, &val, len))
4995 		return -EFAULT;
4996 
4997 	return -ENOTSUPP;
4998 }
4999 
5000 /*
5001  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
5002  * (chapter and verse is quoted at sctp_setsockopt_maxburst())
5003  */
5004 static int sctp_getsockopt_maxburst(struct sock *sk, int len,
5005 				    char __user *optval,
5006 				    int __user *optlen)
5007 {
5008 	int val;
5009 
5010 	if (len < sizeof(int))
5011 		return -EINVAL;
5012 
5013 	len = sizeof(int);
5014 
5015 	val = sctp_sk(sk)->max_burst;
5016 	if (put_user(len, optlen))
5017 		return -EFAULT;
5018 	if (copy_to_user(optval, &val, len))
5019 		return -EFAULT;
5020 
5021 	return -ENOTSUPP;
5022 }
5023 
5024 static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
5025 				    char __user *optval, int __user *optlen)
5026 {
5027 	struct sctp_hmac_algo_param *hmacs;
5028 	__u16 param_len;
5029 
5030 	hmacs = sctp_sk(sk)->ep->auth_hmacs_list;
5031 	param_len = ntohs(hmacs->param_hdr.length);
5032 
5033 	if (len < param_len)
5034 		return -EINVAL;
5035 	if (put_user(len, optlen))
5036 		return -EFAULT;
5037 	if (copy_to_user(optval, hmacs->hmac_ids, len))
5038 		return -EFAULT;
5039 
5040 	return 0;
5041 }
5042 
5043 static int sctp_getsockopt_active_key(struct sock *sk, int len,
5044 				    char __user *optval, int __user *optlen)
5045 {
5046 	struct sctp_authkeyid val;
5047 	struct sctp_association *asoc;
5048 
5049 	if (len < sizeof(struct sctp_authkeyid))
5050 		return -EINVAL;
5051 	if (copy_from_user(&val, optval, sizeof(struct sctp_authkeyid)))
5052 		return -EFAULT;
5053 
5054 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
5055 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
5056 		return -EINVAL;
5057 
5058 	if (asoc)
5059 		val.scact_keynumber = asoc->active_key_id;
5060 	else
5061 		val.scact_keynumber = sctp_sk(sk)->ep->active_key_id;
5062 
5063 	return 0;
5064 }
5065 
5066 static int sctp_getsockopt_peer_auth_chunks(struct sock *sk, int len,
5067 				    char __user *optval, int __user *optlen)
5068 {
5069 	struct sctp_authchunks __user *p = (void __user *)optval;
5070 	struct sctp_authchunks val;
5071 	struct sctp_association *asoc;
5072 	struct sctp_chunks_param *ch;
5073 	char __user *to;
5074 
5075 	if (len <= sizeof(struct sctp_authchunks))
5076 		return -EINVAL;
5077 
5078 	if (copy_from_user(&val, p, sizeof(struct sctp_authchunks)))
5079 		return -EFAULT;
5080 
5081 	to = p->gauth_chunks;
5082 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5083 	if (!asoc)
5084 		return -EINVAL;
5085 
5086 	ch = asoc->peer.peer_chunks;
5087 
5088 	/* See if the user provided enough room for all the data */
5089 	if (len < ntohs(ch->param_hdr.length))
5090 		return -EINVAL;
5091 
5092 	len = ntohs(ch->param_hdr.length);
5093 	if (put_user(len, optlen))
5094 		return -EFAULT;
5095 	if (copy_to_user(to, ch->chunks, len))
5096 		return -EFAULT;
5097 
5098 	return 0;
5099 }
5100 
5101 static int sctp_getsockopt_local_auth_chunks(struct sock *sk, int len,
5102 				    char __user *optval, int __user *optlen)
5103 {
5104 	struct sctp_authchunks __user *p = (void __user *)optval;
5105 	struct sctp_authchunks val;
5106 	struct sctp_association *asoc;
5107 	struct sctp_chunks_param *ch;
5108 	char __user *to;
5109 
5110 	if (len <= sizeof(struct sctp_authchunks))
5111 		return -EINVAL;
5112 
5113 	if (copy_from_user(&val, p, sizeof(struct sctp_authchunks)))
5114 		return -EFAULT;
5115 
5116 	to = p->gauth_chunks;
5117 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5118 	if (!asoc && val.gauth_assoc_id && sctp_style(sk, UDP))
5119 		return -EINVAL;
5120 
5121 	if (asoc)
5122 		ch = (struct sctp_chunks_param*)asoc->c.auth_chunks;
5123 	else
5124 		ch = sctp_sk(sk)->ep->auth_chunk_list;
5125 
5126 	if (len < ntohs(ch->param_hdr.length))
5127 		return -EINVAL;
5128 
5129 	len = ntohs(ch->param_hdr.length);
5130 	if (put_user(len, optlen))
5131 		return -EFAULT;
5132 	if (copy_to_user(to, ch->chunks, len))
5133 		return -EFAULT;
5134 
5135 	return 0;
5136 }
5137 
5138 SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
5139 				char __user *optval, int __user *optlen)
5140 {
5141 	int retval = 0;
5142 	int len;
5143 
5144 	SCTP_DEBUG_PRINTK("sctp_getsockopt(sk: %p... optname: %d)\n",
5145 			  sk, optname);
5146 
5147 	/* I can hardly begin to describe how wrong this is.  This is
5148 	 * so broken as to be worse than useless.  The API draft
5149 	 * REALLY is NOT helpful here...  I am not convinced that the
5150 	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
5151 	 * are at all well-founded.
5152 	 */
5153 	if (level != SOL_SCTP) {
5154 		struct sctp_af *af = sctp_sk(sk)->pf->af;
5155 
5156 		retval = af->getsockopt(sk, level, optname, optval, optlen);
5157 		return retval;
5158 	}
5159 
5160 	if (get_user(len, optlen))
5161 		return -EFAULT;
5162 
5163 	sctp_lock_sock(sk);
5164 
5165 	switch (optname) {
5166 	case SCTP_STATUS:
5167 		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
5168 		break;
5169 	case SCTP_DISABLE_FRAGMENTS:
5170 		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
5171 							   optlen);
5172 		break;
5173 	case SCTP_EVENTS:
5174 		retval = sctp_getsockopt_events(sk, len, optval, optlen);
5175 		break;
5176 	case SCTP_AUTOCLOSE:
5177 		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
5178 		break;
5179 	case SCTP_SOCKOPT_PEELOFF:
5180 		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
5181 		break;
5182 	case SCTP_PEER_ADDR_PARAMS:
5183 		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
5184 							  optlen);
5185 		break;
5186 	case SCTP_DELAYED_ACK_TIME:
5187 		retval = sctp_getsockopt_delayed_ack_time(sk, len, optval,
5188 							  optlen);
5189 		break;
5190 	case SCTP_INITMSG:
5191 		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
5192 		break;
5193 	case SCTP_GET_PEER_ADDRS_NUM_OLD:
5194 		retval = sctp_getsockopt_peer_addrs_num_old(sk, len, optval,
5195 							    optlen);
5196 		break;
5197 	case SCTP_GET_LOCAL_ADDRS_NUM_OLD:
5198 		retval = sctp_getsockopt_local_addrs_num_old(sk, len, optval,
5199 							     optlen);
5200 		break;
5201 	case SCTP_GET_PEER_ADDRS_OLD:
5202 		retval = sctp_getsockopt_peer_addrs_old(sk, len, optval,
5203 							optlen);
5204 		break;
5205 	case SCTP_GET_LOCAL_ADDRS_OLD:
5206 		retval = sctp_getsockopt_local_addrs_old(sk, len, optval,
5207 							 optlen);
5208 		break;
5209 	case SCTP_GET_PEER_ADDRS:
5210 		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
5211 						    optlen);
5212 		break;
5213 	case SCTP_GET_LOCAL_ADDRS:
5214 		retval = sctp_getsockopt_local_addrs(sk, len, optval,
5215 						     optlen);
5216 		break;
5217 	case SCTP_DEFAULT_SEND_PARAM:
5218 		retval = sctp_getsockopt_default_send_param(sk, len,
5219 							    optval, optlen);
5220 		break;
5221 	case SCTP_PRIMARY_ADDR:
5222 		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
5223 		break;
5224 	case SCTP_NODELAY:
5225 		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
5226 		break;
5227 	case SCTP_RTOINFO:
5228 		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
5229 		break;
5230 	case SCTP_ASSOCINFO:
5231 		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
5232 		break;
5233 	case SCTP_I_WANT_MAPPED_V4_ADDR:
5234 		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
5235 		break;
5236 	case SCTP_MAXSEG:
5237 		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
5238 		break;
5239 	case SCTP_GET_PEER_ADDR_INFO:
5240 		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
5241 							optlen);
5242 		break;
5243 	case SCTP_ADAPTATION_LAYER:
5244 		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
5245 							optlen);
5246 		break;
5247 	case SCTP_CONTEXT:
5248 		retval = sctp_getsockopt_context(sk, len, optval, optlen);
5249 		break;
5250 	case SCTP_FRAGMENT_INTERLEAVE:
5251 		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
5252 							     optlen);
5253 		break;
5254 	case SCTP_PARTIAL_DELIVERY_POINT:
5255 		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
5256 								optlen);
5257 		break;
5258 	case SCTP_MAX_BURST:
5259 		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
5260 		break;
5261 	case SCTP_AUTH_KEY:
5262 	case SCTP_AUTH_CHUNK:
5263 	case SCTP_AUTH_DELETE_KEY:
5264 		retval = -EOPNOTSUPP;
5265 		break;
5266 	case SCTP_HMAC_IDENT:
5267 		retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
5268 		break;
5269 	case SCTP_AUTH_ACTIVE_KEY:
5270 		retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
5271 		break;
5272 	case SCTP_PEER_AUTH_CHUNKS:
5273 		retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
5274 							optlen);
5275 		break;
5276 	case SCTP_LOCAL_AUTH_CHUNKS:
5277 		retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
5278 							optlen);
5279 		break;
5280 	default:
5281 		retval = -ENOPROTOOPT;
5282 		break;
5283 	}
5284 
5285 	sctp_release_sock(sk);
5286 	return retval;
5287 }
5288 
5289 static void sctp_hash(struct sock *sk)
5290 {
5291 	/* STUB */
5292 }
5293 
5294 static void sctp_unhash(struct sock *sk)
5295 {
5296 	/* STUB */
5297 }
5298 
5299 /* Check if port is acceptable.  Possibly find first available port.
5300  *
5301  * The port hash table (contained in the 'global' SCTP protocol storage
5302  * returned by struct sctp_protocol *sctp_get_protocol()). The hash
5303  * table is an array of 4096 lists (sctp_bind_hashbucket). Each
5304  * list (the list number is the port number hashed out, so as you
5305  * would expect from a hash function, all the ports in a given list have
5306  * such a number that hashes out to the same list number; you were
5307  * expecting that, right?); so each list has a set of ports, with a
5308  * link to the socket (struct sock) that uses it, the port number and
5309  * a fastreuse flag (FIXME: NPI ipg).
5310  */
5311 static struct sctp_bind_bucket *sctp_bucket_create(
5312 	struct sctp_bind_hashbucket *head, unsigned short snum);
5313 
5314 static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
5315 {
5316 	struct sctp_bind_hashbucket *head; /* hash list */
5317 	struct sctp_bind_bucket *pp; /* hash list port iterator */
5318 	struct hlist_node *node;
5319 	unsigned short snum;
5320 	int ret;
5321 
5322 	snum = ntohs(addr->v4.sin_port);
5323 
5324 	SCTP_DEBUG_PRINTK("sctp_get_port() begins, snum=%d\n", snum);
5325 	sctp_local_bh_disable();
5326 
5327 	if (snum == 0) {
5328 		/* Search for an available port. */
5329 		int low, high, remaining, index;
5330 		unsigned int rover;
5331 
5332 		inet_get_local_port_range(&low, &high);
5333 		remaining = (high - low) + 1;
5334 		rover = net_random() % remaining + low;
5335 
5336 		do {
5337 			rover++;
5338 			if ((rover < low) || (rover > high))
5339 				rover = low;
5340 			index = sctp_phashfn(rover);
5341 			head = &sctp_port_hashtable[index];
5342 			sctp_spin_lock(&head->lock);
5343 			sctp_for_each_hentry(pp, node, &head->chain)
5344 				if (pp->port == rover)
5345 					goto next;
5346 			break;
5347 		next:
5348 			sctp_spin_unlock(&head->lock);
5349 		} while (--remaining > 0);
5350 
5351 		/* Exhausted local port range during search? */
5352 		ret = 1;
5353 		if (remaining <= 0)
5354 			goto fail;
5355 
5356 		/* OK, here is the one we will use.  HEAD (the port
5357 		 * hash table list entry) is non-NULL and we hold it's
5358 		 * mutex.
5359 		 */
5360 		snum = rover;
5361 	} else {
5362 		/* We are given an specific port number; we verify
5363 		 * that it is not being used. If it is used, we will
5364 		 * exahust the search in the hash list corresponding
5365 		 * to the port number (snum) - we detect that with the
5366 		 * port iterator, pp being NULL.
5367 		 */
5368 		head = &sctp_port_hashtable[sctp_phashfn(snum)];
5369 		sctp_spin_lock(&head->lock);
5370 		sctp_for_each_hentry(pp, node, &head->chain) {
5371 			if (pp->port == snum)
5372 				goto pp_found;
5373 		}
5374 	}
5375 	pp = NULL;
5376 	goto pp_not_found;
5377 pp_found:
5378 	if (!hlist_empty(&pp->owner)) {
5379 		/* We had a port hash table hit - there is an
5380 		 * available port (pp != NULL) and it is being
5381 		 * used by other socket (pp->owner not empty); that other
5382 		 * socket is going to be sk2.
5383 		 */
5384 		int reuse = sk->sk_reuse;
5385 		struct sock *sk2;
5386 		struct hlist_node *node;
5387 
5388 		SCTP_DEBUG_PRINTK("sctp_get_port() found a possible match\n");
5389 		if (pp->fastreuse && sk->sk_reuse &&
5390 			sk->sk_state != SCTP_SS_LISTENING)
5391 			goto success;
5392 
5393 		/* Run through the list of sockets bound to the port
5394 		 * (pp->port) [via the pointers bind_next and
5395 		 * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
5396 		 * we get the endpoint they describe and run through
5397 		 * the endpoint's list of IP (v4 or v6) addresses,
5398 		 * comparing each of the addresses with the address of
5399 		 * the socket sk. If we find a match, then that means
5400 		 * that this port/socket (sk) combination are already
5401 		 * in an endpoint.
5402 		 */
5403 		sk_for_each_bound(sk2, node, &pp->owner) {
5404 			struct sctp_endpoint *ep2;
5405 			ep2 = sctp_sk(sk2)->ep;
5406 
5407 			if (reuse && sk2->sk_reuse &&
5408 			    sk2->sk_state != SCTP_SS_LISTENING)
5409 				continue;
5410 
5411 			if (sctp_bind_addr_match(&ep2->base.bind_addr, addr,
5412 						 sctp_sk(sk))) {
5413 				ret = (long)sk2;
5414 				goto fail_unlock;
5415 			}
5416 		}
5417 		SCTP_DEBUG_PRINTK("sctp_get_port(): Found a match\n");
5418 	}
5419 pp_not_found:
5420 	/* If there was a hash table miss, create a new port.  */
5421 	ret = 1;
5422 	if (!pp && !(pp = sctp_bucket_create(head, snum)))
5423 		goto fail_unlock;
5424 
5425 	/* In either case (hit or miss), make sure fastreuse is 1 only
5426 	 * if sk->sk_reuse is too (that is, if the caller requested
5427 	 * SO_REUSEADDR on this socket -sk-).
5428 	 */
5429 	if (hlist_empty(&pp->owner)) {
5430 		if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
5431 			pp->fastreuse = 1;
5432 		else
5433 			pp->fastreuse = 0;
5434 	} else if (pp->fastreuse &&
5435 		(!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
5436 		pp->fastreuse = 0;
5437 
5438 	/* We are set, so fill up all the data in the hash table
5439 	 * entry, tie the socket list information with the rest of the
5440 	 * sockets FIXME: Blurry, NPI (ipg).
5441 	 */
5442 success:
5443 	if (!sctp_sk(sk)->bind_hash) {
5444 		inet_sk(sk)->num = snum;
5445 		sk_add_bind_node(sk, &pp->owner);
5446 		sctp_sk(sk)->bind_hash = pp;
5447 	}
5448 	ret = 0;
5449 
5450 fail_unlock:
5451 	sctp_spin_unlock(&head->lock);
5452 
5453 fail:
5454 	sctp_local_bh_enable();
5455 	return ret;
5456 }
5457 
5458 /* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
5459  * port is requested.
5460  */
5461 static int sctp_get_port(struct sock *sk, unsigned short snum)
5462 {
5463 	long ret;
5464 	union sctp_addr addr;
5465 	struct sctp_af *af = sctp_sk(sk)->pf->af;
5466 
5467 	/* Set up a dummy address struct from the sk. */
5468 	af->from_sk(&addr, sk);
5469 	addr.v4.sin_port = htons(snum);
5470 
5471 	/* Note: sk->sk_num gets filled in if ephemeral port request. */
5472 	ret = sctp_get_port_local(sk, &addr);
5473 
5474 	return (ret ? 1 : 0);
5475 }
5476 
5477 /*
5478  * 3.1.3 listen() - UDP Style Syntax
5479  *
5480  *   By default, new associations are not accepted for UDP style sockets.
5481  *   An application uses listen() to mark a socket as being able to
5482  *   accept new associations.
5483  */
5484 SCTP_STATIC int sctp_seqpacket_listen(struct sock *sk, int backlog)
5485 {
5486 	struct sctp_sock *sp = sctp_sk(sk);
5487 	struct sctp_endpoint *ep = sp->ep;
5488 
5489 	/* Only UDP style sockets that are not peeled off are allowed to
5490 	 * listen().
5491 	 */
5492 	if (!sctp_style(sk, UDP))
5493 		return -EINVAL;
5494 
5495 	/* If backlog is zero, disable listening. */
5496 	if (!backlog) {
5497 		if (sctp_sstate(sk, CLOSED))
5498 			return 0;
5499 
5500 		sctp_unhash_endpoint(ep);
5501 		sk->sk_state = SCTP_SS_CLOSED;
5502 		return 0;
5503 	}
5504 
5505 	/* Return if we are already listening. */
5506 	if (sctp_sstate(sk, LISTENING))
5507 		return 0;
5508 
5509 	/*
5510 	 * If a bind() or sctp_bindx() is not called prior to a listen()
5511 	 * call that allows new associations to be accepted, the system
5512 	 * picks an ephemeral port and will choose an address set equivalent
5513 	 * to binding with a wildcard address.
5514 	 *
5515 	 * This is not currently spelled out in the SCTP sockets
5516 	 * extensions draft, but follows the practice as seen in TCP
5517 	 * sockets.
5518 	 *
5519 	 * Additionally, turn off fastreuse flag since we are not listening
5520 	 */
5521 	sk->sk_state = SCTP_SS_LISTENING;
5522 	if (!ep->base.bind_addr.port) {
5523 		if (sctp_autobind(sk))
5524 			return -EAGAIN;
5525 	} else
5526 		sctp_sk(sk)->bind_hash->fastreuse = 0;
5527 
5528 	sctp_hash_endpoint(ep);
5529 	return 0;
5530 }
5531 
5532 /*
5533  * 4.1.3 listen() - TCP Style Syntax
5534  *
5535  *   Applications uses listen() to ready the SCTP endpoint for accepting
5536  *   inbound associations.
5537  */
5538 SCTP_STATIC int sctp_stream_listen(struct sock *sk, int backlog)
5539 {
5540 	struct sctp_sock *sp = sctp_sk(sk);
5541 	struct sctp_endpoint *ep = sp->ep;
5542 
5543 	/* If backlog is zero, disable listening. */
5544 	if (!backlog) {
5545 		if (sctp_sstate(sk, CLOSED))
5546 			return 0;
5547 
5548 		sctp_unhash_endpoint(ep);
5549 		sk->sk_state = SCTP_SS_CLOSED;
5550 		return 0;
5551 	}
5552 
5553 	if (sctp_sstate(sk, LISTENING))
5554 		return 0;
5555 
5556 	/*
5557 	 * If a bind() or sctp_bindx() is not called prior to a listen()
5558 	 * call that allows new associations to be accepted, the system
5559 	 * picks an ephemeral port and will choose an address set equivalent
5560 	 * to binding with a wildcard address.
5561 	 *
5562 	 * This is not currently spelled out in the SCTP sockets
5563 	 * extensions draft, but follows the practice as seen in TCP
5564 	 * sockets.
5565 	 */
5566 	sk->sk_state = SCTP_SS_LISTENING;
5567 	if (!ep->base.bind_addr.port) {
5568 		if (sctp_autobind(sk))
5569 			return -EAGAIN;
5570 	} else
5571 		sctp_sk(sk)->bind_hash->fastreuse = 0;
5572 
5573 	sk->sk_max_ack_backlog = backlog;
5574 	sctp_hash_endpoint(ep);
5575 	return 0;
5576 }
5577 
5578 /*
5579  *  Move a socket to LISTENING state.
5580  */
5581 int sctp_inet_listen(struct socket *sock, int backlog)
5582 {
5583 	struct sock *sk = sock->sk;
5584 	struct crypto_hash *tfm = NULL;
5585 	int err = -EINVAL;
5586 
5587 	if (unlikely(backlog < 0))
5588 		goto out;
5589 
5590 	sctp_lock_sock(sk);
5591 
5592 	if (sock->state != SS_UNCONNECTED)
5593 		goto out;
5594 
5595 	/* Allocate HMAC for generating cookie. */
5596 	if (sctp_hmac_alg) {
5597 		tfm = crypto_alloc_hash(sctp_hmac_alg, 0, CRYPTO_ALG_ASYNC);
5598 		if (IS_ERR(tfm)) {
5599 			if (net_ratelimit()) {
5600 				printk(KERN_INFO
5601 				       "SCTP: failed to load transform for %s: %ld\n",
5602 					sctp_hmac_alg, PTR_ERR(tfm));
5603 			}
5604 			err = -ENOSYS;
5605 			goto out;
5606 		}
5607 	}
5608 
5609 	switch (sock->type) {
5610 	case SOCK_SEQPACKET:
5611 		err = sctp_seqpacket_listen(sk, backlog);
5612 		break;
5613 	case SOCK_STREAM:
5614 		err = sctp_stream_listen(sk, backlog);
5615 		break;
5616 	default:
5617 		break;
5618 	}
5619 
5620 	if (err)
5621 		goto cleanup;
5622 
5623 	/* Store away the transform reference. */
5624 	sctp_sk(sk)->hmac = tfm;
5625 out:
5626 	sctp_release_sock(sk);
5627 	return err;
5628 cleanup:
5629 	crypto_free_hash(tfm);
5630 	goto out;
5631 }
5632 
5633 /*
5634  * This function is done by modeling the current datagram_poll() and the
5635  * tcp_poll().  Note that, based on these implementations, we don't
5636  * lock the socket in this function, even though it seems that,
5637  * ideally, locking or some other mechanisms can be used to ensure
5638  * the integrity of the counters (sndbuf and wmem_alloc) used
5639  * in this place.  We assume that we don't need locks either until proven
5640  * otherwise.
5641  *
5642  * Another thing to note is that we include the Async I/O support
5643  * here, again, by modeling the current TCP/UDP code.  We don't have
5644  * a good way to test with it yet.
5645  */
5646 unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
5647 {
5648 	struct sock *sk = sock->sk;
5649 	struct sctp_sock *sp = sctp_sk(sk);
5650 	unsigned int mask;
5651 
5652 	poll_wait(file, sk->sk_sleep, wait);
5653 
5654 	/* A TCP-style listening socket becomes readable when the accept queue
5655 	 * is not empty.
5656 	 */
5657 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
5658 		return (!list_empty(&sp->ep->asocs)) ?
5659 			(POLLIN | POLLRDNORM) : 0;
5660 
5661 	mask = 0;
5662 
5663 	/* Is there any exceptional events?  */
5664 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
5665 		mask |= POLLERR;
5666 	if (sk->sk_shutdown & RCV_SHUTDOWN)
5667 		mask |= POLLRDHUP;
5668 	if (sk->sk_shutdown == SHUTDOWN_MASK)
5669 		mask |= POLLHUP;
5670 
5671 	/* Is it readable?  Reconsider this code with TCP-style support.  */
5672 	if (!skb_queue_empty(&sk->sk_receive_queue) ||
5673 	    (sk->sk_shutdown & RCV_SHUTDOWN))
5674 		mask |= POLLIN | POLLRDNORM;
5675 
5676 	/* The association is either gone or not ready.  */
5677 	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
5678 		return mask;
5679 
5680 	/* Is it writable?  */
5681 	if (sctp_writeable(sk)) {
5682 		mask |= POLLOUT | POLLWRNORM;
5683 	} else {
5684 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
5685 		/*
5686 		 * Since the socket is not locked, the buffer
5687 		 * might be made available after the writeable check and
5688 		 * before the bit is set.  This could cause a lost I/O
5689 		 * signal.  tcp_poll() has a race breaker for this race
5690 		 * condition.  Based on their implementation, we put
5691 		 * in the following code to cover it as well.
5692 		 */
5693 		if (sctp_writeable(sk))
5694 			mask |= POLLOUT | POLLWRNORM;
5695 	}
5696 	return mask;
5697 }
5698 
5699 /********************************************************************
5700  * 2nd Level Abstractions
5701  ********************************************************************/
5702 
5703 static struct sctp_bind_bucket *sctp_bucket_create(
5704 	struct sctp_bind_hashbucket *head, unsigned short snum)
5705 {
5706 	struct sctp_bind_bucket *pp;
5707 
5708 	pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
5709 	SCTP_DBG_OBJCNT_INC(bind_bucket);
5710 	if (pp) {
5711 		pp->port = snum;
5712 		pp->fastreuse = 0;
5713 		INIT_HLIST_HEAD(&pp->owner);
5714 		hlist_add_head(&pp->node, &head->chain);
5715 	}
5716 	return pp;
5717 }
5718 
5719 /* Caller must hold hashbucket lock for this tb with local BH disabled */
5720 static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
5721 {
5722 	if (pp && hlist_empty(&pp->owner)) {
5723 		__hlist_del(&pp->node);
5724 		kmem_cache_free(sctp_bucket_cachep, pp);
5725 		SCTP_DBG_OBJCNT_DEC(bind_bucket);
5726 	}
5727 }
5728 
5729 /* Release this socket's reference to a local port.  */
5730 static inline void __sctp_put_port(struct sock *sk)
5731 {
5732 	struct sctp_bind_hashbucket *head =
5733 		&sctp_port_hashtable[sctp_phashfn(inet_sk(sk)->num)];
5734 	struct sctp_bind_bucket *pp;
5735 
5736 	sctp_spin_lock(&head->lock);
5737 	pp = sctp_sk(sk)->bind_hash;
5738 	__sk_del_bind_node(sk);
5739 	sctp_sk(sk)->bind_hash = NULL;
5740 	inet_sk(sk)->num = 0;
5741 	sctp_bucket_destroy(pp);
5742 	sctp_spin_unlock(&head->lock);
5743 }
5744 
5745 void sctp_put_port(struct sock *sk)
5746 {
5747 	sctp_local_bh_disable();
5748 	__sctp_put_port(sk);
5749 	sctp_local_bh_enable();
5750 }
5751 
5752 /*
5753  * The system picks an ephemeral port and choose an address set equivalent
5754  * to binding with a wildcard address.
5755  * One of those addresses will be the primary address for the association.
5756  * This automatically enables the multihoming capability of SCTP.
5757  */
5758 static int sctp_autobind(struct sock *sk)
5759 {
5760 	union sctp_addr autoaddr;
5761 	struct sctp_af *af;
5762 	__be16 port;
5763 
5764 	/* Initialize a local sockaddr structure to INADDR_ANY. */
5765 	af = sctp_sk(sk)->pf->af;
5766 
5767 	port = htons(inet_sk(sk)->num);
5768 	af->inaddr_any(&autoaddr, port);
5769 
5770 	return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
5771 }
5772 
5773 /* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
5774  *
5775  * From RFC 2292
5776  * 4.2 The cmsghdr Structure *
5777  *
5778  * When ancillary data is sent or received, any number of ancillary data
5779  * objects can be specified by the msg_control and msg_controllen members of
5780  * the msghdr structure, because each object is preceded by
5781  * a cmsghdr structure defining the object's length (the cmsg_len member).
5782  * Historically Berkeley-derived implementations have passed only one object
5783  * at a time, but this API allows multiple objects to be
5784  * passed in a single call to sendmsg() or recvmsg(). The following example
5785  * shows two ancillary data objects in a control buffer.
5786  *
5787  *   |<--------------------------- msg_controllen -------------------------->|
5788  *   |                                                                       |
5789  *
5790  *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
5791  *
5792  *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
5793  *   |                                   |                                   |
5794  *
5795  *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
5796  *
5797  *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
5798  *   |                                |  |                                |  |
5799  *
5800  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5801  *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
5802  *
5803  *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
5804  *
5805  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5806  *    ^
5807  *    |
5808  *
5809  * msg_control
5810  * points here
5811  */
5812 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *msg,
5813 				  sctp_cmsgs_t *cmsgs)
5814 {
5815 	struct cmsghdr *cmsg;
5816 
5817 	for (cmsg = CMSG_FIRSTHDR(msg);
5818 	     cmsg != NULL;
5819 	     cmsg = CMSG_NXTHDR((struct msghdr*)msg, cmsg)) {
5820 		if (!CMSG_OK(msg, cmsg))
5821 			return -EINVAL;
5822 
5823 		/* Should we parse this header or ignore?  */
5824 		if (cmsg->cmsg_level != IPPROTO_SCTP)
5825 			continue;
5826 
5827 		/* Strictly check lengths following example in SCM code.  */
5828 		switch (cmsg->cmsg_type) {
5829 		case SCTP_INIT:
5830 			/* SCTP Socket API Extension
5831 			 * 5.2.1 SCTP Initiation Structure (SCTP_INIT)
5832 			 *
5833 			 * This cmsghdr structure provides information for
5834 			 * initializing new SCTP associations with sendmsg().
5835 			 * The SCTP_INITMSG socket option uses this same data
5836 			 * structure.  This structure is not used for
5837 			 * recvmsg().
5838 			 *
5839 			 * cmsg_level    cmsg_type      cmsg_data[]
5840 			 * ------------  ------------   ----------------------
5841 			 * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
5842 			 */
5843 			if (cmsg->cmsg_len !=
5844 			    CMSG_LEN(sizeof(struct sctp_initmsg)))
5845 				return -EINVAL;
5846 			cmsgs->init = (struct sctp_initmsg *)CMSG_DATA(cmsg);
5847 			break;
5848 
5849 		case SCTP_SNDRCV:
5850 			/* SCTP Socket API Extension
5851 			 * 5.2.2 SCTP Header Information Structure(SCTP_SNDRCV)
5852 			 *
5853 			 * This cmsghdr structure specifies SCTP options for
5854 			 * sendmsg() and describes SCTP header information
5855 			 * about a received message through recvmsg().
5856 			 *
5857 			 * cmsg_level    cmsg_type      cmsg_data[]
5858 			 * ------------  ------------   ----------------------
5859 			 * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
5860 			 */
5861 			if (cmsg->cmsg_len !=
5862 			    CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
5863 				return -EINVAL;
5864 
5865 			cmsgs->info =
5866 				(struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
5867 
5868 			/* Minimally, validate the sinfo_flags. */
5869 			if (cmsgs->info->sinfo_flags &
5870 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
5871 			      SCTP_ABORT | SCTP_EOF))
5872 				return -EINVAL;
5873 			break;
5874 
5875 		default:
5876 			return -EINVAL;
5877 		}
5878 	}
5879 	return 0;
5880 }
5881 
5882 /*
5883  * Wait for a packet..
5884  * Note: This function is the same function as in core/datagram.c
5885  * with a few modifications to make lksctp work.
5886  */
5887 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p)
5888 {
5889 	int error;
5890 	DEFINE_WAIT(wait);
5891 
5892 	prepare_to_wait_exclusive(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
5893 
5894 	/* Socket errors? */
5895 	error = sock_error(sk);
5896 	if (error)
5897 		goto out;
5898 
5899 	if (!skb_queue_empty(&sk->sk_receive_queue))
5900 		goto ready;
5901 
5902 	/* Socket shut down?  */
5903 	if (sk->sk_shutdown & RCV_SHUTDOWN)
5904 		goto out;
5905 
5906 	/* Sequenced packets can come disconnected.  If so we report the
5907 	 * problem.
5908 	 */
5909 	error = -ENOTCONN;
5910 
5911 	/* Is there a good reason to think that we may receive some data?  */
5912 	if (list_empty(&sctp_sk(sk)->ep->asocs) && !sctp_sstate(sk, LISTENING))
5913 		goto out;
5914 
5915 	/* Handle signals.  */
5916 	if (signal_pending(current))
5917 		goto interrupted;
5918 
5919 	/* Let another process have a go.  Since we are going to sleep
5920 	 * anyway.  Note: This may cause odd behaviors if the message
5921 	 * does not fit in the user's buffer, but this seems to be the
5922 	 * only way to honor MSG_DONTWAIT realistically.
5923 	 */
5924 	sctp_release_sock(sk);
5925 	*timeo_p = schedule_timeout(*timeo_p);
5926 	sctp_lock_sock(sk);
5927 
5928 ready:
5929 	finish_wait(sk->sk_sleep, &wait);
5930 	return 0;
5931 
5932 interrupted:
5933 	error = sock_intr_errno(*timeo_p);
5934 
5935 out:
5936 	finish_wait(sk->sk_sleep, &wait);
5937 	*err = error;
5938 	return error;
5939 }
5940 
5941 /* Receive a datagram.
5942  * Note: This is pretty much the same routine as in core/datagram.c
5943  * with a few changes to make lksctp work.
5944  */
5945 static struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
5946 					      int noblock, int *err)
5947 {
5948 	int error;
5949 	struct sk_buff *skb;
5950 	long timeo;
5951 
5952 	timeo = sock_rcvtimeo(sk, noblock);
5953 
5954 	SCTP_DEBUG_PRINTK("Timeout: timeo: %ld, MAX: %ld.\n",
5955 			  timeo, MAX_SCHEDULE_TIMEOUT);
5956 
5957 	do {
5958 		/* Again only user level code calls this function,
5959 		 * so nothing interrupt level
5960 		 * will suddenly eat the receive_queue.
5961 		 *
5962 		 *  Look at current nfs client by the way...
5963 		 *  However, this function was corrent in any case. 8)
5964 		 */
5965 		if (flags & MSG_PEEK) {
5966 			spin_lock_bh(&sk->sk_receive_queue.lock);
5967 			skb = skb_peek(&sk->sk_receive_queue);
5968 			if (skb)
5969 				atomic_inc(&skb->users);
5970 			spin_unlock_bh(&sk->sk_receive_queue.lock);
5971 		} else {
5972 			skb = skb_dequeue(&sk->sk_receive_queue);
5973 		}
5974 
5975 		if (skb)
5976 			return skb;
5977 
5978 		/* Caller is allowed not to check sk->sk_err before calling. */
5979 		error = sock_error(sk);
5980 		if (error)
5981 			goto no_packet;
5982 
5983 		if (sk->sk_shutdown & RCV_SHUTDOWN)
5984 			break;
5985 
5986 		/* User doesn't want to wait.  */
5987 		error = -EAGAIN;
5988 		if (!timeo)
5989 			goto no_packet;
5990 	} while (sctp_wait_for_packet(sk, err, &timeo) == 0);
5991 
5992 	return NULL;
5993 
5994 no_packet:
5995 	*err = error;
5996 	return NULL;
5997 }
5998 
5999 /* If sndbuf has changed, wake up per association sndbuf waiters.  */
6000 static void __sctp_write_space(struct sctp_association *asoc)
6001 {
6002 	struct sock *sk = asoc->base.sk;
6003 	struct socket *sock = sk->sk_socket;
6004 
6005 	if ((sctp_wspace(asoc) > 0) && sock) {
6006 		if (waitqueue_active(&asoc->wait))
6007 			wake_up_interruptible(&asoc->wait);
6008 
6009 		if (sctp_writeable(sk)) {
6010 			if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
6011 				wake_up_interruptible(sk->sk_sleep);
6012 
6013 			/* Note that we try to include the Async I/O support
6014 			 * here by modeling from the current TCP/UDP code.
6015 			 * We have not tested with it yet.
6016 			 */
6017 			if (sock->fasync_list &&
6018 			    !(sk->sk_shutdown & SEND_SHUTDOWN))
6019 				sock_wake_async(sock,
6020 						SOCK_WAKE_SPACE, POLL_OUT);
6021 		}
6022 	}
6023 }
6024 
6025 /* Do accounting for the sndbuf space.
6026  * Decrement the used sndbuf space of the corresponding association by the
6027  * data size which was just transmitted(freed).
6028  */
6029 static void sctp_wfree(struct sk_buff *skb)
6030 {
6031 	struct sctp_association *asoc;
6032 	struct sctp_chunk *chunk;
6033 	struct sock *sk;
6034 
6035 	/* Get the saved chunk pointer.  */
6036 	chunk = *((struct sctp_chunk **)(skb->cb));
6037 	asoc = chunk->asoc;
6038 	sk = asoc->base.sk;
6039 	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
6040 				sizeof(struct sk_buff) +
6041 				sizeof(struct sctp_chunk);
6042 
6043 	atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
6044 
6045 	/*
6046 	 * This undoes what is done via sctp_set_owner_w and sk_mem_charge
6047 	 */
6048 	sk->sk_wmem_queued   -= skb->truesize;
6049 	sk_mem_uncharge(sk, skb->truesize);
6050 
6051 	sock_wfree(skb);
6052 	__sctp_write_space(asoc);
6053 
6054 	sctp_association_put(asoc);
6055 }
6056 
6057 /* Do accounting for the receive space on the socket.
6058  * Accounting for the association is done in ulpevent.c
6059  * We set this as a destructor for the cloned data skbs so that
6060  * accounting is done at the correct time.
6061  */
6062 void sctp_sock_rfree(struct sk_buff *skb)
6063 {
6064 	struct sock *sk = skb->sk;
6065 	struct sctp_ulpevent *event = sctp_skb2event(skb);
6066 
6067 	atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
6068 
6069 	/*
6070 	 * Mimic the behavior of sock_rfree
6071 	 */
6072 	sk_mem_uncharge(sk, event->rmem_len);
6073 }
6074 
6075 
6076 /* Helper function to wait for space in the sndbuf.  */
6077 static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
6078 				size_t msg_len)
6079 {
6080 	struct sock *sk = asoc->base.sk;
6081 	int err = 0;
6082 	long current_timeo = *timeo_p;
6083 	DEFINE_WAIT(wait);
6084 
6085 	SCTP_DEBUG_PRINTK("wait_for_sndbuf: asoc=%p, timeo=%ld, msg_len=%zu\n",
6086 			  asoc, (long)(*timeo_p), msg_len);
6087 
6088 	/* Increment the association's refcnt.  */
6089 	sctp_association_hold(asoc);
6090 
6091 	/* Wait on the association specific sndbuf space. */
6092 	for (;;) {
6093 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6094 					  TASK_INTERRUPTIBLE);
6095 		if (!*timeo_p)
6096 			goto do_nonblock;
6097 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6098 		    asoc->base.dead)
6099 			goto do_error;
6100 		if (signal_pending(current))
6101 			goto do_interrupted;
6102 		if (msg_len <= sctp_wspace(asoc))
6103 			break;
6104 
6105 		/* Let another process have a go.  Since we are going
6106 		 * to sleep anyway.
6107 		 */
6108 		sctp_release_sock(sk);
6109 		current_timeo = schedule_timeout(current_timeo);
6110 		BUG_ON(sk != asoc->base.sk);
6111 		sctp_lock_sock(sk);
6112 
6113 		*timeo_p = current_timeo;
6114 	}
6115 
6116 out:
6117 	finish_wait(&asoc->wait, &wait);
6118 
6119 	/* Release the association's refcnt.  */
6120 	sctp_association_put(asoc);
6121 
6122 	return err;
6123 
6124 do_error:
6125 	err = -EPIPE;
6126 	goto out;
6127 
6128 do_interrupted:
6129 	err = sock_intr_errno(*timeo_p);
6130 	goto out;
6131 
6132 do_nonblock:
6133 	err = -EAGAIN;
6134 	goto out;
6135 }
6136 
6137 /* If socket sndbuf has changed, wake up all per association waiters.  */
6138 void sctp_write_space(struct sock *sk)
6139 {
6140 	struct sctp_association *asoc;
6141 	struct list_head *pos;
6142 
6143 	/* Wake up the tasks in each wait queue.  */
6144 	list_for_each(pos, &((sctp_sk(sk))->ep->asocs)) {
6145 		asoc = list_entry(pos, struct sctp_association, asocs);
6146 		__sctp_write_space(asoc);
6147 	}
6148 }
6149 
6150 /* Is there any sndbuf space available on the socket?
6151  *
6152  * Note that sk_wmem_alloc is the sum of the send buffers on all of the
6153  * associations on the same socket.  For a UDP-style socket with
6154  * multiple associations, it is possible for it to be "unwriteable"
6155  * prematurely.  I assume that this is acceptable because
6156  * a premature "unwriteable" is better than an accidental "writeable" which
6157  * would cause an unwanted block under certain circumstances.  For the 1-1
6158  * UDP-style sockets or TCP-style sockets, this code should work.
6159  *  - Daisy
6160  */
6161 static int sctp_writeable(struct sock *sk)
6162 {
6163 	int amt = 0;
6164 
6165 	amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
6166 	if (amt < 0)
6167 		amt = 0;
6168 	return amt;
6169 }
6170 
6171 /* Wait for an association to go into ESTABLISHED state. If timeout is 0,
6172  * returns immediately with EINPROGRESS.
6173  */
6174 static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
6175 {
6176 	struct sock *sk = asoc->base.sk;
6177 	int err = 0;
6178 	long current_timeo = *timeo_p;
6179 	DEFINE_WAIT(wait);
6180 
6181 	SCTP_DEBUG_PRINTK("%s: asoc=%p, timeo=%ld\n", __FUNCTION__, asoc,
6182 			  (long)(*timeo_p));
6183 
6184 	/* Increment the association's refcnt.  */
6185 	sctp_association_hold(asoc);
6186 
6187 	for (;;) {
6188 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6189 					  TASK_INTERRUPTIBLE);
6190 		if (!*timeo_p)
6191 			goto do_nonblock;
6192 		if (sk->sk_shutdown & RCV_SHUTDOWN)
6193 			break;
6194 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6195 		    asoc->base.dead)
6196 			goto do_error;
6197 		if (signal_pending(current))
6198 			goto do_interrupted;
6199 
6200 		if (sctp_state(asoc, ESTABLISHED))
6201 			break;
6202 
6203 		/* Let another process have a go.  Since we are going
6204 		 * to sleep anyway.
6205 		 */
6206 		sctp_release_sock(sk);
6207 		current_timeo = schedule_timeout(current_timeo);
6208 		sctp_lock_sock(sk);
6209 
6210 		*timeo_p = current_timeo;
6211 	}
6212 
6213 out:
6214 	finish_wait(&asoc->wait, &wait);
6215 
6216 	/* Release the association's refcnt.  */
6217 	sctp_association_put(asoc);
6218 
6219 	return err;
6220 
6221 do_error:
6222 	if (asoc->init_err_counter + 1 > asoc->max_init_attempts)
6223 		err = -ETIMEDOUT;
6224 	else
6225 		err = -ECONNREFUSED;
6226 	goto out;
6227 
6228 do_interrupted:
6229 	err = sock_intr_errno(*timeo_p);
6230 	goto out;
6231 
6232 do_nonblock:
6233 	err = -EINPROGRESS;
6234 	goto out;
6235 }
6236 
6237 static int sctp_wait_for_accept(struct sock *sk, long timeo)
6238 {
6239 	struct sctp_endpoint *ep;
6240 	int err = 0;
6241 	DEFINE_WAIT(wait);
6242 
6243 	ep = sctp_sk(sk)->ep;
6244 
6245 
6246 	for (;;) {
6247 		prepare_to_wait_exclusive(sk->sk_sleep, &wait,
6248 					  TASK_INTERRUPTIBLE);
6249 
6250 		if (list_empty(&ep->asocs)) {
6251 			sctp_release_sock(sk);
6252 			timeo = schedule_timeout(timeo);
6253 			sctp_lock_sock(sk);
6254 		}
6255 
6256 		err = -EINVAL;
6257 		if (!sctp_sstate(sk, LISTENING))
6258 			break;
6259 
6260 		err = 0;
6261 		if (!list_empty(&ep->asocs))
6262 			break;
6263 
6264 		err = sock_intr_errno(timeo);
6265 		if (signal_pending(current))
6266 			break;
6267 
6268 		err = -EAGAIN;
6269 		if (!timeo)
6270 			break;
6271 	}
6272 
6273 	finish_wait(sk->sk_sleep, &wait);
6274 
6275 	return err;
6276 }
6277 
6278 static void sctp_wait_for_close(struct sock *sk, long timeout)
6279 {
6280 	DEFINE_WAIT(wait);
6281 
6282 	do {
6283 		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
6284 		if (list_empty(&sctp_sk(sk)->ep->asocs))
6285 			break;
6286 		sctp_release_sock(sk);
6287 		timeout = schedule_timeout(timeout);
6288 		sctp_lock_sock(sk);
6289 	} while (!signal_pending(current) && timeout);
6290 
6291 	finish_wait(sk->sk_sleep, &wait);
6292 }
6293 
6294 static void sctp_sock_rfree_frag(struct sk_buff *skb)
6295 {
6296 	struct sk_buff *frag;
6297 
6298 	if (!skb->data_len)
6299 		goto done;
6300 
6301 	/* Don't forget the fragments. */
6302 	for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next)
6303 		sctp_sock_rfree_frag(frag);
6304 
6305 done:
6306 	sctp_sock_rfree(skb);
6307 }
6308 
6309 static void sctp_skb_set_owner_r_frag(struct sk_buff *skb, struct sock *sk)
6310 {
6311 	struct sk_buff *frag;
6312 
6313 	if (!skb->data_len)
6314 		goto done;
6315 
6316 	/* Don't forget the fragments. */
6317 	for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next)
6318 		sctp_skb_set_owner_r_frag(frag, sk);
6319 
6320 done:
6321 	sctp_skb_set_owner_r(skb, sk);
6322 }
6323 
6324 /* Populate the fields of the newsk from the oldsk and migrate the assoc
6325  * and its messages to the newsk.
6326  */
6327 static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
6328 			      struct sctp_association *assoc,
6329 			      sctp_socket_type_t type)
6330 {
6331 	struct sctp_sock *oldsp = sctp_sk(oldsk);
6332 	struct sctp_sock *newsp = sctp_sk(newsk);
6333 	struct sctp_bind_bucket *pp; /* hash list port iterator */
6334 	struct sctp_endpoint *newep = newsp->ep;
6335 	struct sk_buff *skb, *tmp;
6336 	struct sctp_ulpevent *event;
6337 	struct sctp_bind_hashbucket *head;
6338 
6339 	/* Migrate socket buffer sizes and all the socket level options to the
6340 	 * new socket.
6341 	 */
6342 	newsk->sk_sndbuf = oldsk->sk_sndbuf;
6343 	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
6344 	/* Brute force copy old sctp opt. */
6345 	inet_sk_copy_descendant(newsk, oldsk);
6346 
6347 	/* Restore the ep value that was overwritten with the above structure
6348 	 * copy.
6349 	 */
6350 	newsp->ep = newep;
6351 	newsp->hmac = NULL;
6352 
6353 	/* Hook this new socket in to the bind_hash list. */
6354 	head = &sctp_port_hashtable[sctp_phashfn(inet_sk(oldsk)->num)];
6355 	sctp_local_bh_disable();
6356 	sctp_spin_lock(&head->lock);
6357 	pp = sctp_sk(oldsk)->bind_hash;
6358 	sk_add_bind_node(newsk, &pp->owner);
6359 	sctp_sk(newsk)->bind_hash = pp;
6360 	inet_sk(newsk)->num = inet_sk(oldsk)->num;
6361 	sctp_spin_unlock(&head->lock);
6362 	sctp_local_bh_enable();
6363 
6364 	/* Copy the bind_addr list from the original endpoint to the new
6365 	 * endpoint so that we can handle restarts properly
6366 	 */
6367 	sctp_bind_addr_dup(&newsp->ep->base.bind_addr,
6368 				&oldsp->ep->base.bind_addr, GFP_KERNEL);
6369 
6370 	/* Move any messages in the old socket's receive queue that are for the
6371 	 * peeled off association to the new socket's receive queue.
6372 	 */
6373 	sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
6374 		event = sctp_skb2event(skb);
6375 		if (event->asoc == assoc) {
6376 			sctp_sock_rfree_frag(skb);
6377 			__skb_unlink(skb, &oldsk->sk_receive_queue);
6378 			__skb_queue_tail(&newsk->sk_receive_queue, skb);
6379 			sctp_skb_set_owner_r_frag(skb, newsk);
6380 		}
6381 	}
6382 
6383 	/* Clean up any messages pending delivery due to partial
6384 	 * delivery.   Three cases:
6385 	 * 1) No partial deliver;  no work.
6386 	 * 2) Peeling off partial delivery; keep pd_lobby in new pd_lobby.
6387 	 * 3) Peeling off non-partial delivery; move pd_lobby to receive_queue.
6388 	 */
6389 	skb_queue_head_init(&newsp->pd_lobby);
6390 	atomic_set(&sctp_sk(newsk)->pd_mode, assoc->ulpq.pd_mode);
6391 
6392 	if (atomic_read(&sctp_sk(oldsk)->pd_mode)) {
6393 		struct sk_buff_head *queue;
6394 
6395 		/* Decide which queue to move pd_lobby skbs to. */
6396 		if (assoc->ulpq.pd_mode) {
6397 			queue = &newsp->pd_lobby;
6398 		} else
6399 			queue = &newsk->sk_receive_queue;
6400 
6401 		/* Walk through the pd_lobby, looking for skbs that
6402 		 * need moved to the new socket.
6403 		 */
6404 		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
6405 			event = sctp_skb2event(skb);
6406 			if (event->asoc == assoc) {
6407 				sctp_sock_rfree_frag(skb);
6408 				__skb_unlink(skb, &oldsp->pd_lobby);
6409 				__skb_queue_tail(queue, skb);
6410 				sctp_skb_set_owner_r_frag(skb, newsk);
6411 			}
6412 		}
6413 
6414 		/* Clear up any skbs waiting for the partial
6415 		 * delivery to finish.
6416 		 */
6417 		if (assoc->ulpq.pd_mode)
6418 			sctp_clear_pd(oldsk, NULL);
6419 
6420 	}
6421 
6422 	sctp_skb_for_each(skb, &assoc->ulpq.reasm, tmp) {
6423 		sctp_sock_rfree_frag(skb);
6424 		sctp_skb_set_owner_r_frag(skb, newsk);
6425 	}
6426 
6427 	sctp_skb_for_each(skb, &assoc->ulpq.lobby, tmp) {
6428 		sctp_sock_rfree_frag(skb);
6429 		sctp_skb_set_owner_r_frag(skb, newsk);
6430 	}
6431 
6432 	/* Set the type of socket to indicate that it is peeled off from the
6433 	 * original UDP-style socket or created with the accept() call on a
6434 	 * TCP-style socket..
6435 	 */
6436 	newsp->type = type;
6437 
6438 	/* Mark the new socket "in-use" by the user so that any packets
6439 	 * that may arrive on the association after we've moved it are
6440 	 * queued to the backlog.  This prevents a potential race between
6441 	 * backlog processing on the old socket and new-packet processing
6442 	 * on the new socket.
6443 	 *
6444 	 * The caller has just allocated newsk so we can guarantee that other
6445 	 * paths won't try to lock it and then oldsk.
6446 	 */
6447 	lock_sock_nested(newsk, SINGLE_DEPTH_NESTING);
6448 	sctp_assoc_migrate(assoc, newsk);
6449 
6450 	/* If the association on the newsk is already closed before accept()
6451 	 * is called, set RCV_SHUTDOWN flag.
6452 	 */
6453 	if (sctp_state(assoc, CLOSED) && sctp_style(newsk, TCP))
6454 		newsk->sk_shutdown |= RCV_SHUTDOWN;
6455 
6456 	newsk->sk_state = SCTP_SS_ESTABLISHED;
6457 	sctp_release_sock(newsk);
6458 }
6459 
6460 
6461 DEFINE_PROTO_INUSE(sctp)
6462 
6463 /* This proto struct describes the ULP interface for SCTP.  */
6464 struct proto sctp_prot = {
6465 	.name        =	"SCTP",
6466 	.owner       =	THIS_MODULE,
6467 	.close       =	sctp_close,
6468 	.connect     =	sctp_connect,
6469 	.disconnect  =	sctp_disconnect,
6470 	.accept      =	sctp_accept,
6471 	.ioctl       =	sctp_ioctl,
6472 	.init        =	sctp_init_sock,
6473 	.destroy     =	sctp_destroy_sock,
6474 	.shutdown    =	sctp_shutdown,
6475 	.setsockopt  =	sctp_setsockopt,
6476 	.getsockopt  =	sctp_getsockopt,
6477 	.sendmsg     =	sctp_sendmsg,
6478 	.recvmsg     =	sctp_recvmsg,
6479 	.bind        =	sctp_bind,
6480 	.backlog_rcv =	sctp_backlog_rcv,
6481 	.hash        =	sctp_hash,
6482 	.unhash      =	sctp_unhash,
6483 	.get_port    =	sctp_get_port,
6484 	.obj_size    =  sizeof(struct sctp_sock),
6485 	.sysctl_mem  =  sysctl_sctp_mem,
6486 	.sysctl_rmem =  sysctl_sctp_rmem,
6487 	.sysctl_wmem =  sysctl_sctp_wmem,
6488 	.memory_pressure = &sctp_memory_pressure,
6489 	.enter_memory_pressure = sctp_enter_memory_pressure,
6490 	.memory_allocated = &sctp_memory_allocated,
6491 	.sockets_allocated = &sctp_sockets_allocated,
6492 	REF_PROTO_INUSE(sctp)
6493 };
6494 
6495 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6496 DEFINE_PROTO_INUSE(sctpv6)
6497 
6498 struct proto sctpv6_prot = {
6499 	.name		= "SCTPv6",
6500 	.owner		= THIS_MODULE,
6501 	.close		= sctp_close,
6502 	.connect	= sctp_connect,
6503 	.disconnect	= sctp_disconnect,
6504 	.accept		= sctp_accept,
6505 	.ioctl		= sctp_ioctl,
6506 	.init		= sctp_init_sock,
6507 	.destroy	= sctp_destroy_sock,
6508 	.shutdown	= sctp_shutdown,
6509 	.setsockopt	= sctp_setsockopt,
6510 	.getsockopt	= sctp_getsockopt,
6511 	.sendmsg	= sctp_sendmsg,
6512 	.recvmsg	= sctp_recvmsg,
6513 	.bind		= sctp_bind,
6514 	.backlog_rcv	= sctp_backlog_rcv,
6515 	.hash		= sctp_hash,
6516 	.unhash		= sctp_unhash,
6517 	.get_port	= sctp_get_port,
6518 	.obj_size	= sizeof(struct sctp6_sock),
6519 	.sysctl_mem	= sysctl_sctp_mem,
6520 	.sysctl_rmem	= sysctl_sctp_rmem,
6521 	.sysctl_wmem	= sysctl_sctp_wmem,
6522 	.memory_pressure = &sctp_memory_pressure,
6523 	.enter_memory_pressure = sctp_enter_memory_pressure,
6524 	.memory_allocated = &sctp_memory_allocated,
6525 	.sockets_allocated = &sctp_sockets_allocated,
6526 	REF_PROTO_INUSE(sctpv6)
6527 };
6528 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
6529