1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2001, 2004
3  * Copyright (c) 1999-2000 Cisco, Inc.
4  * Copyright (c) 1999-2001 Motorola, Inc.
5  * Copyright (c) 2001-2003 Intel Corp.
6  * Copyright (c) 2001-2002 Nokia, Inc.
7  * Copyright (c) 2001 La Monte H.P. Yarroll
8  *
9  * This file is part of the SCTP kernel implementation
10  *
11  * These functions interface with the sockets layer to implement the
12  * SCTP Extensions for the Sockets API.
13  *
14  * Note that the descriptions from the specification are USER level
15  * functions--this file is the functions which populate the struct proto
16  * for SCTP which is the BOTTOM of the sockets interface.
17  *
18  * This SCTP implementation is free software;
19  * you can redistribute it and/or modify it under the terms of
20  * the GNU General Public License as published by
21  * the Free Software Foundation; either version 2, or (at your option)
22  * any later version.
23  *
24  * This SCTP implementation is distributed in the hope that it
25  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
26  *                 ************************
27  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
28  * See the GNU General Public License for more details.
29  *
30  * You should have received a copy of the GNU General Public License
31  * along with GNU CC; see the file COPYING.  If not, write to
32  * the Free Software Foundation, 59 Temple Place - Suite 330,
33  * Boston, MA 02111-1307, USA.
34  *
35  * Please send any bug reports or fixes you make to the
36  * email address(es):
37  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
38  *
39  * Or submit a bug report through the following website:
40  *    http://www.sf.net/projects/lksctp
41  *
42  * Written or modified by:
43  *    La Monte H.P. Yarroll <piggy@acm.org>
44  *    Narasimha Budihal     <narsi@refcode.org>
45  *    Karl Knutson          <karl@athena.chicago.il.us>
46  *    Jon Grimm             <jgrimm@us.ibm.com>
47  *    Xingang Guo           <xingang.guo@intel.com>
48  *    Daisy Chang           <daisyc@us.ibm.com>
49  *    Sridhar Samudrala     <samudrala@us.ibm.com>
50  *    Inaky Perez-Gonzalez  <inaky.gonzalez@intel.com>
51  *    Ardelle Fan	    <ardelle.fan@intel.com>
52  *    Ryan Layer	    <rmlayer@us.ibm.com>
53  *    Anup Pemmaiah         <pemmaiah@cc.usu.edu>
54  *    Kevin Gao             <kevin.gao@intel.com>
55  *
56  * Any bugs reported given to us we will try to fix... any fixes shared will
57  * be incorporated into the next SCTP release.
58  */
59 
60 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
61 
62 #include <linux/types.h>
63 #include <linux/kernel.h>
64 #include <linux/wait.h>
65 #include <linux/time.h>
66 #include <linux/ip.h>
67 #include <linux/capability.h>
68 #include <linux/fcntl.h>
69 #include <linux/poll.h>
70 #include <linux/init.h>
71 #include <linux/crypto.h>
72 #include <linux/slab.h>
73 
74 #include <net/ip.h>
75 #include <net/icmp.h>
76 #include <net/route.h>
77 #include <net/ipv6.h>
78 #include <net/inet_common.h>
79 
80 #include <linux/socket.h> /* for sa_family_t */
81 #include <net/sock.h>
82 #include <net/sctp/sctp.h>
83 #include <net/sctp/sm.h>
84 
85 /* WARNING:  Please do not remove the SCTP_STATIC attribute to
86  * any of the functions below as they are used to export functions
87  * used by a project regression testsuite.
88  */
89 
90 /* Forward declarations for internal helper functions. */
91 static int sctp_writeable(struct sock *sk);
92 static void sctp_wfree(struct sk_buff *skb);
93 static int sctp_wait_for_sndbuf(struct sctp_association *, long *timeo_p,
94 				size_t msg_len);
95 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p);
96 static int sctp_wait_for_connect(struct sctp_association *, long *timeo_p);
97 static int sctp_wait_for_accept(struct sock *sk, long timeo);
98 static void sctp_wait_for_close(struct sock *sk, long timeo);
99 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
100 					union sctp_addr *addr, int len);
101 static int sctp_bindx_add(struct sock *, struct sockaddr *, int);
102 static int sctp_bindx_rem(struct sock *, struct sockaddr *, int);
103 static int sctp_send_asconf_add_ip(struct sock *, struct sockaddr *, int);
104 static int sctp_send_asconf_del_ip(struct sock *, struct sockaddr *, int);
105 static int sctp_send_asconf(struct sctp_association *asoc,
106 			    struct sctp_chunk *chunk);
107 static int sctp_do_bind(struct sock *, union sctp_addr *, int);
108 static int sctp_autobind(struct sock *sk);
109 static void sctp_sock_migrate(struct sock *, struct sock *,
110 			      struct sctp_association *, sctp_socket_type_t);
111 static char *sctp_hmac_alg = SCTP_COOKIE_HMAC_ALG;
112 
113 extern struct kmem_cache *sctp_bucket_cachep;
114 extern long sysctl_sctp_mem[3];
115 extern int sysctl_sctp_rmem[3];
116 extern int sysctl_sctp_wmem[3];
117 
118 static int sctp_memory_pressure;
119 static atomic_long_t sctp_memory_allocated;
120 struct percpu_counter sctp_sockets_allocated;
121 
sctp_enter_memory_pressure(struct sock * sk)122 static void sctp_enter_memory_pressure(struct sock *sk)
123 {
124 	sctp_memory_pressure = 1;
125 }
126 
127 
128 /* Get the sndbuf space available at the time on the association.  */
sctp_wspace(struct sctp_association * asoc)129 static inline int sctp_wspace(struct sctp_association *asoc)
130 {
131 	int amt;
132 
133 	if (asoc->ep->sndbuf_policy)
134 		amt = asoc->sndbuf_used;
135 	else
136 		amt = sk_wmem_alloc_get(asoc->base.sk);
137 
138 	if (amt >= asoc->base.sk->sk_sndbuf) {
139 		if (asoc->base.sk->sk_userlocks & SOCK_SNDBUF_LOCK)
140 			amt = 0;
141 		else {
142 			amt = sk_stream_wspace(asoc->base.sk);
143 			if (amt < 0)
144 				amt = 0;
145 		}
146 	} else {
147 		amt = asoc->base.sk->sk_sndbuf - amt;
148 	}
149 	return amt;
150 }
151 
152 /* Increment the used sndbuf space count of the corresponding association by
153  * the size of the outgoing data chunk.
154  * Also, set the skb destructor for sndbuf accounting later.
155  *
156  * Since it is always 1-1 between chunk and skb, and also a new skb is always
157  * allocated for chunk bundling in sctp_packet_transmit(), we can use the
158  * destructor in the data chunk skb for the purpose of the sndbuf space
159  * tracking.
160  */
sctp_set_owner_w(struct sctp_chunk * chunk)161 static inline void sctp_set_owner_w(struct sctp_chunk *chunk)
162 {
163 	struct sctp_association *asoc = chunk->asoc;
164 	struct sock *sk = asoc->base.sk;
165 
166 	/* The sndbuf space is tracked per association.  */
167 	sctp_association_hold(asoc);
168 
169 	skb_set_owner_w(chunk->skb, sk);
170 
171 	chunk->skb->destructor = sctp_wfree;
172 	/* Save the chunk pointer in skb for sctp_wfree to use later.  */
173 	*((struct sctp_chunk **)(chunk->skb->cb)) = chunk;
174 
175 	asoc->sndbuf_used += SCTP_DATA_SNDSIZE(chunk) +
176 				sizeof(struct sk_buff) +
177 				sizeof(struct sctp_chunk);
178 
179 	atomic_add(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
180 	sk->sk_wmem_queued += chunk->skb->truesize;
181 	sk_mem_charge(sk, chunk->skb->truesize);
182 }
183 
184 /* Verify that this is a valid address. */
sctp_verify_addr(struct sock * sk,union sctp_addr * addr,int len)185 static inline int sctp_verify_addr(struct sock *sk, union sctp_addr *addr,
186 				   int len)
187 {
188 	struct sctp_af *af;
189 
190 	/* Verify basic sockaddr. */
191 	af = sctp_sockaddr_af(sctp_sk(sk), addr, len);
192 	if (!af)
193 		return -EINVAL;
194 
195 	/* Is this a valid SCTP address?  */
196 	if (!af->addr_valid(addr, sctp_sk(sk), NULL))
197 		return -EINVAL;
198 
199 	if (!sctp_sk(sk)->pf->send_verify(sctp_sk(sk), (addr)))
200 		return -EINVAL;
201 
202 	return 0;
203 }
204 
205 /* Look up the association by its id.  If this is not a UDP-style
206  * socket, the ID field is always ignored.
207  */
sctp_id2assoc(struct sock * sk,sctp_assoc_t id)208 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id)
209 {
210 	struct sctp_association *asoc = NULL;
211 
212 	/* If this is not a UDP-style socket, assoc id should be ignored. */
213 	if (!sctp_style(sk, UDP)) {
214 		/* Return NULL if the socket state is not ESTABLISHED. It
215 		 * could be a TCP-style listening socket or a socket which
216 		 * hasn't yet called connect() to establish an association.
217 		 */
218 		if (!sctp_sstate(sk, ESTABLISHED))
219 			return NULL;
220 
221 		/* Get the first and the only association from the list. */
222 		if (!list_empty(&sctp_sk(sk)->ep->asocs))
223 			asoc = list_entry(sctp_sk(sk)->ep->asocs.next,
224 					  struct sctp_association, asocs);
225 		return asoc;
226 	}
227 
228 	/* Otherwise this is a UDP-style socket. */
229 	if (!id || (id == (sctp_assoc_t)-1))
230 		return NULL;
231 
232 	spin_lock_bh(&sctp_assocs_id_lock);
233 	asoc = (struct sctp_association *)idr_find(&sctp_assocs_id, (int)id);
234 	spin_unlock_bh(&sctp_assocs_id_lock);
235 
236 	if (!asoc || (asoc->base.sk != sk) || asoc->base.dead)
237 		return NULL;
238 
239 	return asoc;
240 }
241 
242 /* Look up the transport from an address and an assoc id. If both address and
243  * id are specified, the associations matching the address and the id should be
244  * the same.
245  */
sctp_addr_id2transport(struct sock * sk,struct sockaddr_storage * addr,sctp_assoc_t id)246 static struct sctp_transport *sctp_addr_id2transport(struct sock *sk,
247 					      struct sockaddr_storage *addr,
248 					      sctp_assoc_t id)
249 {
250 	struct sctp_association *addr_asoc = NULL, *id_asoc = NULL;
251 	struct sctp_transport *transport;
252 	union sctp_addr *laddr = (union sctp_addr *)addr;
253 
254 	addr_asoc = sctp_endpoint_lookup_assoc(sctp_sk(sk)->ep,
255 					       laddr,
256 					       &transport);
257 
258 	if (!addr_asoc)
259 		return NULL;
260 
261 	id_asoc = sctp_id2assoc(sk, id);
262 	if (id_asoc && (id_asoc != addr_asoc))
263 		return NULL;
264 
265 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
266 						(union sctp_addr *)addr);
267 
268 	return transport;
269 }
270 
271 /* API 3.1.2 bind() - UDP Style Syntax
272  * The syntax of bind() is,
273  *
274  *   ret = bind(int sd, struct sockaddr *addr, int addrlen);
275  *
276  *   sd      - the socket descriptor returned by socket().
277  *   addr    - the address structure (struct sockaddr_in or struct
278  *             sockaddr_in6 [RFC 2553]),
279  *   addr_len - the size of the address structure.
280  */
sctp_bind(struct sock * sk,struct sockaddr * addr,int addr_len)281 SCTP_STATIC int sctp_bind(struct sock *sk, struct sockaddr *addr, int addr_len)
282 {
283 	int retval = 0;
284 
285 	sctp_lock_sock(sk);
286 
287 	SCTP_DEBUG_PRINTK("sctp_bind(sk: %p, addr: %p, addr_len: %d)\n",
288 			  sk, addr, addr_len);
289 
290 	/* Disallow binding twice. */
291 	if (!sctp_sk(sk)->ep->base.bind_addr.port)
292 		retval = sctp_do_bind(sk, (union sctp_addr *)addr,
293 				      addr_len);
294 	else
295 		retval = -EINVAL;
296 
297 	sctp_release_sock(sk);
298 
299 	return retval;
300 }
301 
302 static long sctp_get_port_local(struct sock *, union sctp_addr *);
303 
304 /* Verify this is a valid sockaddr. */
sctp_sockaddr_af(struct sctp_sock * opt,union sctp_addr * addr,int len)305 static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
306 					union sctp_addr *addr, int len)
307 {
308 	struct sctp_af *af;
309 
310 	/* Check minimum size.  */
311 	if (len < sizeof (struct sockaddr))
312 		return NULL;
313 
314 	/* V4 mapped address are really of AF_INET family */
315 	if (addr->sa.sa_family == AF_INET6 &&
316 	    ipv6_addr_v4mapped(&addr->v6.sin6_addr)) {
317 		if (!opt->pf->af_supported(AF_INET, opt))
318 			return NULL;
319 	} else {
320 		/* Does this PF support this AF? */
321 		if (!opt->pf->af_supported(addr->sa.sa_family, opt))
322 			return NULL;
323 	}
324 
325 	/* If we get this far, af is valid. */
326 	af = sctp_get_af_specific(addr->sa.sa_family);
327 
328 	if (len < af->sockaddr_len)
329 		return NULL;
330 
331 	return af;
332 }
333 
334 /* Bind a local address either to an endpoint or to an association.  */
sctp_do_bind(struct sock * sk,union sctp_addr * addr,int len)335 SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
336 {
337 	struct sctp_sock *sp = sctp_sk(sk);
338 	struct sctp_endpoint *ep = sp->ep;
339 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
340 	struct sctp_af *af;
341 	unsigned short snum;
342 	int ret = 0;
343 
344 	/* Common sockaddr verification. */
345 	af = sctp_sockaddr_af(sp, addr, len);
346 	if (!af) {
347 		SCTP_DEBUG_PRINTK("sctp_do_bind(sk: %p, newaddr: %p, len: %d) EINVAL\n",
348 				  sk, addr, len);
349 		return -EINVAL;
350 	}
351 
352 	snum = ntohs(addr->v4.sin_port);
353 
354 	SCTP_DEBUG_PRINTK_IPADDR("sctp_do_bind(sk: %p, new addr: ",
355 				 ", port: %d, new port: %d, len: %d)\n",
356 				 sk,
357 				 addr,
358 				 bp->port, snum,
359 				 len);
360 
361 	/* PF specific bind() address verification. */
362 	if (!sp->pf->bind_verify(sp, addr))
363 		return -EADDRNOTAVAIL;
364 
365 	/* We must either be unbound, or bind to the same port.
366 	 * It's OK to allow 0 ports if we are already bound.
367 	 * We'll just inhert an already bound port in this case
368 	 */
369 	if (bp->port) {
370 		if (!snum)
371 			snum = bp->port;
372 		else if (snum != bp->port) {
373 			SCTP_DEBUG_PRINTK("sctp_do_bind:"
374 				  " New port %d does not match existing port "
375 				  "%d.\n", snum, bp->port);
376 			return -EINVAL;
377 		}
378 	}
379 
380 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
381 		return -EACCES;
382 
383 	/* See if the address matches any of the addresses we may have
384 	 * already bound before checking against other endpoints.
385 	 */
386 	if (sctp_bind_addr_match(bp, addr, sp))
387 		return -EINVAL;
388 
389 	/* Make sure we are allowed to bind here.
390 	 * The function sctp_get_port_local() does duplicate address
391 	 * detection.
392 	 */
393 	addr->v4.sin_port = htons(snum);
394 	if ((ret = sctp_get_port_local(sk, addr))) {
395 		return -EADDRINUSE;
396 	}
397 
398 	/* Refresh ephemeral port.  */
399 	if (!bp->port)
400 		bp->port = inet_sk(sk)->inet_num;
401 
402 	/* Add the address to the bind address list.
403 	 * Use GFP_ATOMIC since BHs will be disabled.
404 	 */
405 	ret = sctp_add_bind_addr(bp, addr, SCTP_ADDR_SRC, GFP_ATOMIC);
406 
407 	/* Copy back into socket for getsockname() use. */
408 	if (!ret) {
409 		inet_sk(sk)->inet_sport = htons(inet_sk(sk)->inet_num);
410 		af->to_sk_saddr(addr, sk);
411 	}
412 
413 	return ret;
414 }
415 
416  /* ADDIP Section 4.1.1 Congestion Control of ASCONF Chunks
417  *
418  * R1) One and only one ASCONF Chunk MAY be in transit and unacknowledged
419  * at any one time.  If a sender, after sending an ASCONF chunk, decides
420  * it needs to transfer another ASCONF Chunk, it MUST wait until the
421  * ASCONF-ACK Chunk returns from the previous ASCONF Chunk before sending a
422  * subsequent ASCONF. Note this restriction binds each side, so at any
423  * time two ASCONF may be in-transit on any given association (one sent
424  * from each endpoint).
425  */
sctp_send_asconf(struct sctp_association * asoc,struct sctp_chunk * chunk)426 static int sctp_send_asconf(struct sctp_association *asoc,
427 			    struct sctp_chunk *chunk)
428 {
429 	int		retval = 0;
430 
431 	/* If there is an outstanding ASCONF chunk, queue it for later
432 	 * transmission.
433 	 */
434 	if (asoc->addip_last_asconf) {
435 		list_add_tail(&chunk->list, &asoc->addip_chunk_list);
436 		goto out;
437 	}
438 
439 	/* Hold the chunk until an ASCONF_ACK is received. */
440 	sctp_chunk_hold(chunk);
441 	retval = sctp_primitive_ASCONF(asoc, chunk);
442 	if (retval)
443 		sctp_chunk_free(chunk);
444 	else
445 		asoc->addip_last_asconf = chunk;
446 
447 out:
448 	return retval;
449 }
450 
451 /* Add a list of addresses as bind addresses to local endpoint or
452  * association.
453  *
454  * Basically run through each address specified in the addrs/addrcnt
455  * array/length pair, determine if it is IPv6 or IPv4 and call
456  * sctp_do_bind() on it.
457  *
458  * If any of them fails, then the operation will be reversed and the
459  * ones that were added will be removed.
460  *
461  * Only sctp_setsockopt_bindx() is supposed to call this function.
462  */
sctp_bindx_add(struct sock * sk,struct sockaddr * addrs,int addrcnt)463 static int sctp_bindx_add(struct sock *sk, struct sockaddr *addrs, int addrcnt)
464 {
465 	int cnt;
466 	int retval = 0;
467 	void *addr_buf;
468 	struct sockaddr *sa_addr;
469 	struct sctp_af *af;
470 
471 	SCTP_DEBUG_PRINTK("sctp_bindx_add (sk: %p, addrs: %p, addrcnt: %d)\n",
472 			  sk, addrs, addrcnt);
473 
474 	addr_buf = addrs;
475 	for (cnt = 0; cnt < addrcnt; cnt++) {
476 		/* The list may contain either IPv4 or IPv6 address;
477 		 * determine the address length for walking thru the list.
478 		 */
479 		sa_addr = (struct sockaddr *)addr_buf;
480 		af = sctp_get_af_specific(sa_addr->sa_family);
481 		if (!af) {
482 			retval = -EINVAL;
483 			goto err_bindx_add;
484 		}
485 
486 		retval = sctp_do_bind(sk, (union sctp_addr *)sa_addr,
487 				      af->sockaddr_len);
488 
489 		addr_buf += af->sockaddr_len;
490 
491 err_bindx_add:
492 		if (retval < 0) {
493 			/* Failed. Cleanup the ones that have been added */
494 			if (cnt > 0)
495 				sctp_bindx_rem(sk, addrs, cnt);
496 			return retval;
497 		}
498 	}
499 
500 	return retval;
501 }
502 
503 /* Send an ASCONF chunk with Add IP address parameters to all the peers of the
504  * associations that are part of the endpoint indicating that a list of local
505  * addresses are added to the endpoint.
506  *
507  * If any of the addresses is already in the bind address list of the
508  * association, we do not send the chunk for that association.  But it will not
509  * affect other associations.
510  *
511  * Only sctp_setsockopt_bindx() is supposed to call this function.
512  */
sctp_send_asconf_add_ip(struct sock * sk,struct sockaddr * addrs,int addrcnt)513 static int sctp_send_asconf_add_ip(struct sock		*sk,
514 				   struct sockaddr	*addrs,
515 				   int 			addrcnt)
516 {
517 	struct sctp_sock		*sp;
518 	struct sctp_endpoint		*ep;
519 	struct sctp_association		*asoc;
520 	struct sctp_bind_addr		*bp;
521 	struct sctp_chunk		*chunk;
522 	struct sctp_sockaddr_entry	*laddr;
523 	union sctp_addr			*addr;
524 	union sctp_addr			saveaddr;
525 	void				*addr_buf;
526 	struct sctp_af			*af;
527 	struct list_head		*p;
528 	int 				i;
529 	int 				retval = 0;
530 
531 	if (!sctp_addip_enable)
532 		return retval;
533 
534 	sp = sctp_sk(sk);
535 	ep = sp->ep;
536 
537 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
538 			  __func__, sk, addrs, addrcnt);
539 
540 	list_for_each_entry(asoc, &ep->asocs, asocs) {
541 
542 		if (!asoc->peer.asconf_capable)
543 			continue;
544 
545 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
546 			continue;
547 
548 		if (!sctp_state(asoc, ESTABLISHED))
549 			continue;
550 
551 		/* Check if any address in the packed array of addresses is
552 		 * in the bind address list of the association. If so,
553 		 * do not send the asconf chunk to its peer, but continue with
554 		 * other associations.
555 		 */
556 		addr_buf = addrs;
557 		for (i = 0; i < addrcnt; i++) {
558 			addr = (union sctp_addr *)addr_buf;
559 			af = sctp_get_af_specific(addr->v4.sin_family);
560 			if (!af) {
561 				retval = -EINVAL;
562 				goto out;
563 			}
564 
565 			if (sctp_assoc_lookup_laddr(asoc, addr))
566 				break;
567 
568 			addr_buf += af->sockaddr_len;
569 		}
570 		if (i < addrcnt)
571 			continue;
572 
573 		/* Use the first valid address in bind addr list of
574 		 * association as Address Parameter of ASCONF CHUNK.
575 		 */
576 		bp = &asoc->base.bind_addr;
577 		p = bp->address_list.next;
578 		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
579 		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
580 						   addrcnt, SCTP_PARAM_ADD_IP);
581 		if (!chunk) {
582 			retval = -ENOMEM;
583 			goto out;
584 		}
585 
586 		retval = sctp_send_asconf(asoc, chunk);
587 		if (retval)
588 			goto out;
589 
590 		/* Add the new addresses to the bind address list with
591 		 * use_as_src set to 0.
592 		 */
593 		addr_buf = addrs;
594 		for (i = 0; i < addrcnt; i++) {
595 			addr = (union sctp_addr *)addr_buf;
596 			af = sctp_get_af_specific(addr->v4.sin_family);
597 			memcpy(&saveaddr, addr, af->sockaddr_len);
598 			retval = sctp_add_bind_addr(bp, &saveaddr,
599 						    SCTP_ADDR_NEW, GFP_ATOMIC);
600 			addr_buf += af->sockaddr_len;
601 		}
602 	}
603 
604 out:
605 	return retval;
606 }
607 
608 /* Remove a list of addresses from bind addresses list.  Do not remove the
609  * last address.
610  *
611  * Basically run through each address specified in the addrs/addrcnt
612  * array/length pair, determine if it is IPv6 or IPv4 and call
613  * sctp_del_bind() on it.
614  *
615  * If any of them fails, then the operation will be reversed and the
616  * ones that were removed will be added back.
617  *
618  * At least one address has to be left; if only one address is
619  * available, the operation will return -EBUSY.
620  *
621  * Only sctp_setsockopt_bindx() is supposed to call this function.
622  */
sctp_bindx_rem(struct sock * sk,struct sockaddr * addrs,int addrcnt)623 static int sctp_bindx_rem(struct sock *sk, struct sockaddr *addrs, int addrcnt)
624 {
625 	struct sctp_sock *sp = sctp_sk(sk);
626 	struct sctp_endpoint *ep = sp->ep;
627 	int cnt;
628 	struct sctp_bind_addr *bp = &ep->base.bind_addr;
629 	int retval = 0;
630 	void *addr_buf;
631 	union sctp_addr *sa_addr;
632 	struct sctp_af *af;
633 
634 	SCTP_DEBUG_PRINTK("sctp_bindx_rem (sk: %p, addrs: %p, addrcnt: %d)\n",
635 			  sk, addrs, addrcnt);
636 
637 	addr_buf = addrs;
638 	for (cnt = 0; cnt < addrcnt; cnt++) {
639 		/* If the bind address list is empty or if there is only one
640 		 * bind address, there is nothing more to be removed (we need
641 		 * at least one address here).
642 		 */
643 		if (list_empty(&bp->address_list) ||
644 		    (sctp_list_single_entry(&bp->address_list))) {
645 			retval = -EBUSY;
646 			goto err_bindx_rem;
647 		}
648 
649 		sa_addr = (union sctp_addr *)addr_buf;
650 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
651 		if (!af) {
652 			retval = -EINVAL;
653 			goto err_bindx_rem;
654 		}
655 
656 		if (!af->addr_valid(sa_addr, sp, NULL)) {
657 			retval = -EADDRNOTAVAIL;
658 			goto err_bindx_rem;
659 		}
660 
661 		if (sa_addr->v4.sin_port != htons(bp->port)) {
662 			retval = -EINVAL;
663 			goto err_bindx_rem;
664 		}
665 
666 		/* FIXME - There is probably a need to check if sk->sk_saddr and
667 		 * sk->sk_rcv_addr are currently set to one of the addresses to
668 		 * be removed. This is something which needs to be looked into
669 		 * when we are fixing the outstanding issues with multi-homing
670 		 * socket routing and failover schemes. Refer to comments in
671 		 * sctp_do_bind(). -daisy
672 		 */
673 		retval = sctp_del_bind_addr(bp, sa_addr);
674 
675 		addr_buf += af->sockaddr_len;
676 err_bindx_rem:
677 		if (retval < 0) {
678 			/* Failed. Add the ones that has been removed back */
679 			if (cnt > 0)
680 				sctp_bindx_add(sk, addrs, cnt);
681 			return retval;
682 		}
683 	}
684 
685 	return retval;
686 }
687 
688 /* Send an ASCONF chunk with Delete IP address parameters to all the peers of
689  * the associations that are part of the endpoint indicating that a list of
690  * local addresses are removed from the endpoint.
691  *
692  * If any of the addresses is already in the bind address list of the
693  * association, we do not send the chunk for that association.  But it will not
694  * affect other associations.
695  *
696  * Only sctp_setsockopt_bindx() is supposed to call this function.
697  */
sctp_send_asconf_del_ip(struct sock * sk,struct sockaddr * addrs,int addrcnt)698 static int sctp_send_asconf_del_ip(struct sock		*sk,
699 				   struct sockaddr	*addrs,
700 				   int			addrcnt)
701 {
702 	struct sctp_sock	*sp;
703 	struct sctp_endpoint	*ep;
704 	struct sctp_association	*asoc;
705 	struct sctp_transport	*transport;
706 	struct sctp_bind_addr	*bp;
707 	struct sctp_chunk	*chunk;
708 	union sctp_addr		*laddr;
709 	void			*addr_buf;
710 	struct sctp_af		*af;
711 	struct sctp_sockaddr_entry *saddr;
712 	int 			i;
713 	int 			retval = 0;
714 
715 	if (!sctp_addip_enable)
716 		return retval;
717 
718 	sp = sctp_sk(sk);
719 	ep = sp->ep;
720 
721 	SCTP_DEBUG_PRINTK("%s: (sk: %p, addrs: %p, addrcnt: %d)\n",
722 			  __func__, sk, addrs, addrcnt);
723 
724 	list_for_each_entry(asoc, &ep->asocs, asocs) {
725 
726 		if (!asoc->peer.asconf_capable)
727 			continue;
728 
729 		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_DEL_IP)
730 			continue;
731 
732 		if (!sctp_state(asoc, ESTABLISHED))
733 			continue;
734 
735 		/* Check if any address in the packed array of addresses is
736 		 * not present in the bind address list of the association.
737 		 * If so, do not send the asconf chunk to its peer, but
738 		 * continue with other associations.
739 		 */
740 		addr_buf = addrs;
741 		for (i = 0; i < addrcnt; i++) {
742 			laddr = (union sctp_addr *)addr_buf;
743 			af = sctp_get_af_specific(laddr->v4.sin_family);
744 			if (!af) {
745 				retval = -EINVAL;
746 				goto out;
747 			}
748 
749 			if (!sctp_assoc_lookup_laddr(asoc, laddr))
750 				break;
751 
752 			addr_buf += af->sockaddr_len;
753 		}
754 		if (i < addrcnt)
755 			continue;
756 
757 		/* Find one address in the association's bind address list
758 		 * that is not in the packed array of addresses. This is to
759 		 * make sure that we do not delete all the addresses in the
760 		 * association.
761 		 */
762 		bp = &asoc->base.bind_addr;
763 		laddr = sctp_find_unmatch_addr(bp, (union sctp_addr *)addrs,
764 					       addrcnt, sp);
765 		if (!laddr)
766 			continue;
767 
768 		/* We do not need RCU protection throughout this loop
769 		 * because this is done under a socket lock from the
770 		 * setsockopt call.
771 		 */
772 		chunk = sctp_make_asconf_update_ip(asoc, laddr, addrs, addrcnt,
773 						   SCTP_PARAM_DEL_IP);
774 		if (!chunk) {
775 			retval = -ENOMEM;
776 			goto out;
777 		}
778 
779 		/* Reset use_as_src flag for the addresses in the bind address
780 		 * list that are to be deleted.
781 		 */
782 		addr_buf = addrs;
783 		for (i = 0; i < addrcnt; i++) {
784 			laddr = (union sctp_addr *)addr_buf;
785 			af = sctp_get_af_specific(laddr->v4.sin_family);
786 			list_for_each_entry(saddr, &bp->address_list, list) {
787 				if (sctp_cmp_addr_exact(&saddr->a, laddr))
788 					saddr->state = SCTP_ADDR_DEL;
789 			}
790 			addr_buf += af->sockaddr_len;
791 		}
792 
793 		/* Update the route and saddr entries for all the transports
794 		 * as some of the addresses in the bind address list are
795 		 * about to be deleted and cannot be used as source addresses.
796 		 */
797 		list_for_each_entry(transport, &asoc->peer.transport_addr_list,
798 					transports) {
799 			dst_release(transport->dst);
800 			sctp_transport_route(transport, NULL,
801 					     sctp_sk(asoc->base.sk));
802 		}
803 
804 		retval = sctp_send_asconf(asoc, chunk);
805 	}
806 out:
807 	return retval;
808 }
809 
810 /* Helper for tunneling sctp_bindx() requests through sctp_setsockopt()
811  *
812  * API 8.1
813  * int sctp_bindx(int sd, struct sockaddr *addrs, int addrcnt,
814  *                int flags);
815  *
816  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
817  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
818  * or IPv6 addresses.
819  *
820  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
821  * Section 3.1.2 for this usage.
822  *
823  * addrs is a pointer to an array of one or more socket addresses. Each
824  * address is contained in its appropriate structure (i.e. struct
825  * sockaddr_in or struct sockaddr_in6) the family of the address type
826  * must be used to distinguish the address length (note that this
827  * representation is termed a "packed array" of addresses). The caller
828  * specifies the number of addresses in the array with addrcnt.
829  *
830  * On success, sctp_bindx() returns 0. On failure, sctp_bindx() returns
831  * -1, and sets errno to the appropriate error code.
832  *
833  * For SCTP, the port given in each socket address must be the same, or
834  * sctp_bindx() will fail, setting errno to EINVAL.
835  *
836  * The flags parameter is formed from the bitwise OR of zero or more of
837  * the following currently defined flags:
838  *
839  * SCTP_BINDX_ADD_ADDR
840  *
841  * SCTP_BINDX_REM_ADDR
842  *
843  * SCTP_BINDX_ADD_ADDR directs SCTP to add the given addresses to the
844  * association, and SCTP_BINDX_REM_ADDR directs SCTP to remove the given
845  * addresses from the association. The two flags are mutually exclusive;
846  * if both are given, sctp_bindx() will fail with EINVAL. A caller may
847  * not remove all addresses from an association; sctp_bindx() will
848  * reject such an attempt with EINVAL.
849  *
850  * An application can use sctp_bindx(SCTP_BINDX_ADD_ADDR) to associate
851  * additional addresses with an endpoint after calling bind().  Or use
852  * sctp_bindx(SCTP_BINDX_REM_ADDR) to remove some addresses a listening
853  * socket is associated with so that no new association accepted will be
854  * associated with those addresses. If the endpoint supports dynamic
855  * address a SCTP_BINDX_REM_ADDR or SCTP_BINDX_ADD_ADDR may cause a
856  * endpoint to send the appropriate message to the peer to change the
857  * peers address lists.
858  *
859  * Adding and removing addresses from a connected association is
860  * optional functionality. Implementations that do not support this
861  * functionality should return EOPNOTSUPP.
862  *
863  * Basically do nothing but copying the addresses from user to kernel
864  * land and invoking either sctp_bindx_add() or sctp_bindx_rem() on the sk.
865  * This is used for tunneling the sctp_bindx() request through sctp_setsockopt()
866  * from userspace.
867  *
868  * We don't use copy_from_user() for optimization: we first do the
869  * sanity checks (buffer size -fast- and access check-healthy
870  * pointer); if all of those succeed, then we can alloc the memory
871  * (expensive operation) needed to copy the data to kernel. Then we do
872  * the copying without checking the user space area
873  * (__copy_from_user()).
874  *
875  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
876  * it.
877  *
878  * sk        The sk of the socket
879  * addrs     The pointer to the addresses in user land
880  * addrssize Size of the addrs buffer
881  * op        Operation to perform (add or remove, see the flags of
882  *           sctp_bindx)
883  *
884  * Returns 0 if ok, <0 errno code on error.
885  */
sctp_setsockopt_bindx(struct sock * sk,struct sockaddr __user * addrs,int addrs_size,int op)886 SCTP_STATIC int sctp_setsockopt_bindx(struct sock* sk,
887 				      struct sockaddr __user *addrs,
888 				      int addrs_size, int op)
889 {
890 	struct sockaddr *kaddrs;
891 	int err;
892 	int addrcnt = 0;
893 	int walk_size = 0;
894 	struct sockaddr *sa_addr;
895 	void *addr_buf;
896 	struct sctp_af *af;
897 
898 	SCTP_DEBUG_PRINTK("sctp_setsocktopt_bindx: sk %p addrs %p"
899 			  " addrs_size %d opt %d\n", sk, addrs, addrs_size, op);
900 
901 	if (unlikely(addrs_size <= 0))
902 		return -EINVAL;
903 
904 	/* Check the user passed a healthy pointer.  */
905 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
906 		return -EFAULT;
907 
908 	/* Alloc space for the address array in kernel memory.  */
909 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
910 	if (unlikely(!kaddrs))
911 		return -ENOMEM;
912 
913 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
914 		kfree(kaddrs);
915 		return -EFAULT;
916 	}
917 
918 	/* Walk through the addrs buffer and count the number of addresses. */
919 	addr_buf = kaddrs;
920 	while (walk_size < addrs_size) {
921 		if (walk_size + sizeof(sa_family_t) > addrs_size) {
922 			kfree(kaddrs);
923 			return -EINVAL;
924 		}
925 
926 		sa_addr = (struct sockaddr *)addr_buf;
927 		af = sctp_get_af_specific(sa_addr->sa_family);
928 
929 		/* If the address family is not supported or if this address
930 		 * causes the address buffer to overflow return EINVAL.
931 		 */
932 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
933 			kfree(kaddrs);
934 			return -EINVAL;
935 		}
936 		addrcnt++;
937 		addr_buf += af->sockaddr_len;
938 		walk_size += af->sockaddr_len;
939 	}
940 
941 	/* Do the work. */
942 	switch (op) {
943 	case SCTP_BINDX_ADD_ADDR:
944 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
945 		if (err)
946 			goto out;
947 		err = sctp_send_asconf_add_ip(sk, kaddrs, addrcnt);
948 		break;
949 
950 	case SCTP_BINDX_REM_ADDR:
951 		err = sctp_bindx_rem(sk, kaddrs, addrcnt);
952 		if (err)
953 			goto out;
954 		err = sctp_send_asconf_del_ip(sk, kaddrs, addrcnt);
955 		break;
956 
957 	default:
958 		err = -EINVAL;
959 		break;
960 	}
961 
962 out:
963 	kfree(kaddrs);
964 
965 	return err;
966 }
967 
968 /* __sctp_connect(struct sock* sk, struct sockaddr *kaddrs, int addrs_size)
969  *
970  * Common routine for handling connect() and sctp_connectx().
971  * Connect will come in with just a single address.
972  */
__sctp_connect(struct sock * sk,struct sockaddr * kaddrs,int addrs_size,sctp_assoc_t * assoc_id)973 static int __sctp_connect(struct sock* sk,
974 			  struct sockaddr *kaddrs,
975 			  int addrs_size,
976 			  sctp_assoc_t *assoc_id)
977 {
978 	struct sctp_sock *sp;
979 	struct sctp_endpoint *ep;
980 	struct sctp_association *asoc = NULL;
981 	struct sctp_association *asoc2;
982 	struct sctp_transport *transport;
983 	union sctp_addr to;
984 	struct sctp_af *af;
985 	sctp_scope_t scope;
986 	long timeo;
987 	int err = 0;
988 	int addrcnt = 0;
989 	int walk_size = 0;
990 	union sctp_addr *sa_addr = NULL;
991 	void *addr_buf;
992 	unsigned short port;
993 	unsigned int f_flags = 0;
994 
995 	sp = sctp_sk(sk);
996 	ep = sp->ep;
997 
998 	/* connect() cannot be done on a socket that is already in ESTABLISHED
999 	 * state - UDP-style peeled off socket or a TCP-style socket that
1000 	 * is already connected.
1001 	 * It cannot be done even on a TCP-style listening socket.
1002 	 */
1003 	if (sctp_sstate(sk, ESTABLISHED) ||
1004 	    (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))) {
1005 		err = -EISCONN;
1006 		goto out_free;
1007 	}
1008 
1009 	/* Walk through the addrs buffer and count the number of addresses. */
1010 	addr_buf = kaddrs;
1011 	while (walk_size < addrs_size) {
1012 		if (walk_size + sizeof(sa_family_t) > addrs_size) {
1013 			err = -EINVAL;
1014 			goto out_free;
1015 		}
1016 
1017 		sa_addr = (union sctp_addr *)addr_buf;
1018 		af = sctp_get_af_specific(sa_addr->sa.sa_family);
1019 
1020 		/* If the address family is not supported or if this address
1021 		 * causes the address buffer to overflow return EINVAL.
1022 		 */
1023 		if (!af || (walk_size + af->sockaddr_len) > addrs_size) {
1024 			err = -EINVAL;
1025 			goto out_free;
1026 		}
1027 
1028 		port = ntohs(sa_addr->v4.sin_port);
1029 
1030 		/* Save current address so we can work with it */
1031 		memcpy(&to, sa_addr, af->sockaddr_len);
1032 
1033 		err = sctp_verify_addr(sk, &to, af->sockaddr_len);
1034 		if (err)
1035 			goto out_free;
1036 
1037 		/* Make sure the destination port is correctly set
1038 		 * in all addresses.
1039 		 */
1040 		if (asoc && asoc->peer.port && asoc->peer.port != port)
1041 			goto out_free;
1042 
1043 
1044 		/* Check if there already is a matching association on the
1045 		 * endpoint (other than the one created here).
1046 		 */
1047 		asoc2 = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1048 		if (asoc2 && asoc2 != asoc) {
1049 			if (asoc2->state >= SCTP_STATE_ESTABLISHED)
1050 				err = -EISCONN;
1051 			else
1052 				err = -EALREADY;
1053 			goto out_free;
1054 		}
1055 
1056 		/* If we could not find a matching association on the endpoint,
1057 		 * make sure that there is no peeled-off association matching
1058 		 * the peer address even on another socket.
1059 		 */
1060 		if (sctp_endpoint_is_peeled_off(ep, &to)) {
1061 			err = -EADDRNOTAVAIL;
1062 			goto out_free;
1063 		}
1064 
1065 		if (!asoc) {
1066 			/* If a bind() or sctp_bindx() is not called prior to
1067 			 * an sctp_connectx() call, the system picks an
1068 			 * ephemeral port and will choose an address set
1069 			 * equivalent to binding with a wildcard address.
1070 			 */
1071 			if (!ep->base.bind_addr.port) {
1072 				if (sctp_autobind(sk)) {
1073 					err = -EAGAIN;
1074 					goto out_free;
1075 				}
1076 			} else {
1077 				/*
1078 				 * If an unprivileged user inherits a 1-many
1079 				 * style socket with open associations on a
1080 				 * privileged port, it MAY be permitted to
1081 				 * accept new associations, but it SHOULD NOT
1082 				 * be permitted to open new associations.
1083 				 */
1084 				if (ep->base.bind_addr.port < PROT_SOCK &&
1085 				    !capable(CAP_NET_BIND_SERVICE)) {
1086 					err = -EACCES;
1087 					goto out_free;
1088 				}
1089 			}
1090 
1091 			scope = sctp_scope(&to);
1092 			asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1093 			if (!asoc) {
1094 				err = -ENOMEM;
1095 				goto out_free;
1096 			}
1097 
1098 			err = sctp_assoc_set_bind_addr_from_ep(asoc, scope,
1099 							      GFP_KERNEL);
1100 			if (err < 0) {
1101 				goto out_free;
1102 			}
1103 
1104 		}
1105 
1106 		/* Prime the peer's transport structures.  */
1107 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL,
1108 						SCTP_UNKNOWN);
1109 		if (!transport) {
1110 			err = -ENOMEM;
1111 			goto out_free;
1112 		}
1113 
1114 		addrcnt++;
1115 		addr_buf += af->sockaddr_len;
1116 		walk_size += af->sockaddr_len;
1117 	}
1118 
1119 	/* In case the user of sctp_connectx() wants an association
1120 	 * id back, assign one now.
1121 	 */
1122 	if (assoc_id) {
1123 		err = sctp_assoc_set_id(asoc, GFP_KERNEL);
1124 		if (err < 0)
1125 			goto out_free;
1126 	}
1127 
1128 	err = sctp_primitive_ASSOCIATE(asoc, NULL);
1129 	if (err < 0) {
1130 		goto out_free;
1131 	}
1132 
1133 	/* Initialize sk's dport and daddr for getpeername() */
1134 	inet_sk(sk)->inet_dport = htons(asoc->peer.port);
1135 	af = sctp_get_af_specific(sa_addr->sa.sa_family);
1136 	af->to_sk_daddr(sa_addr, sk);
1137 	sk->sk_err = 0;
1138 
1139 	/* in-kernel sockets don't generally have a file allocated to them
1140 	 * if all they do is call sock_create_kern().
1141 	 */
1142 	if (sk->sk_socket->file)
1143 		f_flags = sk->sk_socket->file->f_flags;
1144 
1145 	timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK);
1146 
1147 	err = sctp_wait_for_connect(asoc, &timeo);
1148 	if ((err == 0 || err == -EINPROGRESS) && assoc_id)
1149 		*assoc_id = asoc->assoc_id;
1150 
1151 	/* Don't free association on exit. */
1152 	asoc = NULL;
1153 
1154 out_free:
1155 
1156 	SCTP_DEBUG_PRINTK("About to exit __sctp_connect() free asoc: %p"
1157 			  " kaddrs: %p err: %d\n",
1158 			  asoc, kaddrs, err);
1159 	if (asoc)
1160 		sctp_association_free(asoc);
1161 	return err;
1162 }
1163 
1164 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
1165  *
1166  * API 8.9
1167  * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt,
1168  * 			sctp_assoc_t *asoc);
1169  *
1170  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
1171  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
1172  * or IPv6 addresses.
1173  *
1174  * A single address may be specified as INADDR_ANY or IN6ADDR_ANY, see
1175  * Section 3.1.2 for this usage.
1176  *
1177  * addrs is a pointer to an array of one or more socket addresses. Each
1178  * address is contained in its appropriate structure (i.e. struct
1179  * sockaddr_in or struct sockaddr_in6) the family of the address type
1180  * must be used to distengish the address length (note that this
1181  * representation is termed a "packed array" of addresses). The caller
1182  * specifies the number of addresses in the array with addrcnt.
1183  *
1184  * On success, sctp_connectx() returns 0. It also sets the assoc_id to
1185  * the association id of the new association.  On failure, sctp_connectx()
1186  * returns -1, and sets errno to the appropriate error code.  The assoc_id
1187  * is not touched by the kernel.
1188  *
1189  * For SCTP, the port given in each socket address must be the same, or
1190  * sctp_connectx() will fail, setting errno to EINVAL.
1191  *
1192  * An application can use sctp_connectx to initiate an association with
1193  * an endpoint that is multi-homed.  Much like sctp_bindx() this call
1194  * allows a caller to specify multiple addresses at which a peer can be
1195  * reached.  The way the SCTP stack uses the list of addresses to set up
1196  * the association is implementation dependent.  This function only
1197  * specifies that the stack will try to make use of all the addresses in
1198  * the list when needed.
1199  *
1200  * Note that the list of addresses passed in is only used for setting up
1201  * the association.  It does not necessarily equal the set of addresses
1202  * the peer uses for the resulting association.  If the caller wants to
1203  * find out the set of peer addresses, it must use sctp_getpaddrs() to
1204  * retrieve them after the association has been set up.
1205  *
1206  * Basically do nothing but copying the addresses from user to kernel
1207  * land and invoking either sctp_connectx(). This is used for tunneling
1208  * the sctp_connectx() request through sctp_setsockopt() from userspace.
1209  *
1210  * We don't use copy_from_user() for optimization: we first do the
1211  * sanity checks (buffer size -fast- and access check-healthy
1212  * pointer); if all of those succeed, then we can alloc the memory
1213  * (expensive operation) needed to copy the data to kernel. Then we do
1214  * the copying without checking the user space area
1215  * (__copy_from_user()).
1216  *
1217  * On exit there is no need to do sockfd_put(), sys_setsockopt() does
1218  * it.
1219  *
1220  * sk        The sk of the socket
1221  * addrs     The pointer to the addresses in user land
1222  * addrssize Size of the addrs buffer
1223  *
1224  * Returns >=0 if ok, <0 errno code on error.
1225  */
__sctp_setsockopt_connectx(struct sock * sk,struct sockaddr __user * addrs,int addrs_size,sctp_assoc_t * assoc_id)1226 SCTP_STATIC int __sctp_setsockopt_connectx(struct sock* sk,
1227 				      struct sockaddr __user *addrs,
1228 				      int addrs_size,
1229 				      sctp_assoc_t *assoc_id)
1230 {
1231 	int err = 0;
1232 	struct sockaddr *kaddrs;
1233 
1234 	SCTP_DEBUG_PRINTK("%s - sk %p addrs %p addrs_size %d\n",
1235 			  __func__, sk, addrs, addrs_size);
1236 
1237 	if (unlikely(addrs_size <= 0))
1238 		return -EINVAL;
1239 
1240 	/* Check the user passed a healthy pointer.  */
1241 	if (unlikely(!access_ok(VERIFY_READ, addrs, addrs_size)))
1242 		return -EFAULT;
1243 
1244 	/* Alloc space for the address array in kernel memory.  */
1245 	kaddrs = kmalloc(addrs_size, GFP_KERNEL);
1246 	if (unlikely(!kaddrs))
1247 		return -ENOMEM;
1248 
1249 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
1250 		err = -EFAULT;
1251 	} else {
1252 		err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
1253 	}
1254 
1255 	kfree(kaddrs);
1256 
1257 	return err;
1258 }
1259 
1260 /*
1261  * This is an older interface.  It's kept for backward compatibility
1262  * to the option that doesn't provide association id.
1263  */
sctp_setsockopt_connectx_old(struct sock * sk,struct sockaddr __user * addrs,int addrs_size)1264 SCTP_STATIC int sctp_setsockopt_connectx_old(struct sock* sk,
1265 				      struct sockaddr __user *addrs,
1266 				      int addrs_size)
1267 {
1268 	return __sctp_setsockopt_connectx(sk, addrs, addrs_size, NULL);
1269 }
1270 
1271 /*
1272  * New interface for the API.  The since the API is done with a socket
1273  * option, to make it simple we feed back the association id is as a return
1274  * indication to the call.  Error is always negative and association id is
1275  * always positive.
1276  */
sctp_setsockopt_connectx(struct sock * sk,struct sockaddr __user * addrs,int addrs_size)1277 SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
1278 				      struct sockaddr __user *addrs,
1279 				      int addrs_size)
1280 {
1281 	sctp_assoc_t assoc_id = 0;
1282 	int err = 0;
1283 
1284 	err = __sctp_setsockopt_connectx(sk, addrs, addrs_size, &assoc_id);
1285 
1286 	if (err)
1287 		return err;
1288 	else
1289 		return assoc_id;
1290 }
1291 
1292 /*
1293  * New (hopefully final) interface for the API.
1294  * We use the sctp_getaddrs_old structure so that use-space library
1295  * can avoid any unnecessary allocations.   The only defferent part
1296  * is that we store the actual length of the address buffer into the
1297  * addrs_num structure member.  That way we can re-use the existing
1298  * code.
1299  */
sctp_getsockopt_connectx3(struct sock * sk,int len,char __user * optval,int __user * optlen)1300 SCTP_STATIC int sctp_getsockopt_connectx3(struct sock* sk, int len,
1301 					char __user *optval,
1302 					int __user *optlen)
1303 {
1304 	struct sctp_getaddrs_old param;
1305 	sctp_assoc_t assoc_id = 0;
1306 	int err = 0;
1307 
1308 	if (len < sizeof(param))
1309 		return -EINVAL;
1310 
1311 	if (copy_from_user(&param, optval, sizeof(param)))
1312 		return -EFAULT;
1313 
1314 	err = __sctp_setsockopt_connectx(sk,
1315 			(struct sockaddr __user *)param.addrs,
1316 			param.addr_num, &assoc_id);
1317 
1318 	if (err == 0 || err == -EINPROGRESS) {
1319 		if (copy_to_user(optval, &assoc_id, sizeof(assoc_id)))
1320 			return -EFAULT;
1321 		if (put_user(sizeof(assoc_id), optlen))
1322 			return -EFAULT;
1323 	}
1324 
1325 	return err;
1326 }
1327 
1328 /* API 3.1.4 close() - UDP Style Syntax
1329  * Applications use close() to perform graceful shutdown (as described in
1330  * Section 10.1 of [SCTP]) on ALL the associations currently represented
1331  * by a UDP-style socket.
1332  *
1333  * The syntax is
1334  *
1335  *   ret = close(int sd);
1336  *
1337  *   sd      - the socket descriptor of the associations to be closed.
1338  *
1339  * To gracefully shutdown a specific association represented by the
1340  * UDP-style socket, an application should use the sendmsg() call,
1341  * passing no user data, but including the appropriate flag in the
1342  * ancillary data (see Section xxxx).
1343  *
1344  * If sd in the close() call is a branched-off socket representing only
1345  * one association, the shutdown is performed on that association only.
1346  *
1347  * 4.1.6 close() - TCP Style Syntax
1348  *
1349  * Applications use close() to gracefully close down an association.
1350  *
1351  * The syntax is:
1352  *
1353  *    int close(int sd);
1354  *
1355  *      sd      - the socket descriptor of the association to be closed.
1356  *
1357  * After an application calls close() on a socket descriptor, no further
1358  * socket operations will succeed on that descriptor.
1359  *
1360  * API 7.1.4 SO_LINGER
1361  *
1362  * An application using the TCP-style socket can use this option to
1363  * perform the SCTP ABORT primitive.  The linger option structure is:
1364  *
1365  *  struct  linger {
1366  *     int     l_onoff;                // option on/off
1367  *     int     l_linger;               // linger time
1368  * };
1369  *
1370  * To enable the option, set l_onoff to 1.  If the l_linger value is set
1371  * to 0, calling close() is the same as the ABORT primitive.  If the
1372  * value is set to a negative value, the setsockopt() call will return
1373  * an error.  If the value is set to a positive value linger_time, the
1374  * close() can be blocked for at most linger_time ms.  If the graceful
1375  * shutdown phase does not finish during this period, close() will
1376  * return but the graceful shutdown phase continues in the system.
1377  */
sctp_close(struct sock * sk,long timeout)1378 SCTP_STATIC void sctp_close(struct sock *sk, long timeout)
1379 {
1380 	struct sctp_endpoint *ep;
1381 	struct sctp_association *asoc;
1382 	struct list_head *pos, *temp;
1383 
1384 	SCTP_DEBUG_PRINTK("sctp_close(sk: 0x%p, timeout:%ld)\n", sk, timeout);
1385 
1386 	sctp_lock_sock(sk);
1387 	sk->sk_shutdown = SHUTDOWN_MASK;
1388 	sk->sk_state = SCTP_SS_CLOSING;
1389 
1390 	ep = sctp_sk(sk)->ep;
1391 
1392 	/* Walk all associations on an endpoint.  */
1393 	list_for_each_safe(pos, temp, &ep->asocs) {
1394 		asoc = list_entry(pos, struct sctp_association, asocs);
1395 
1396 		if (sctp_style(sk, TCP)) {
1397 			/* A closed association can still be in the list if
1398 			 * it belongs to a TCP-style listening socket that is
1399 			 * not yet accepted. If so, free it. If not, send an
1400 			 * ABORT or SHUTDOWN based on the linger options.
1401 			 */
1402 			if (sctp_state(asoc, CLOSED)) {
1403 				sctp_unhash_established(asoc);
1404 				sctp_association_free(asoc);
1405 				continue;
1406 			}
1407 		}
1408 
1409 		if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
1410 			struct sctp_chunk *chunk;
1411 
1412 			chunk = sctp_make_abort_user(asoc, NULL, 0);
1413 			if (chunk)
1414 				sctp_primitive_ABORT(asoc, chunk);
1415 		} else
1416 			sctp_primitive_SHUTDOWN(asoc, NULL);
1417 	}
1418 
1419 	/* Clean up any skbs sitting on the receive queue.  */
1420 	sctp_queue_purge_ulpevents(&sk->sk_receive_queue);
1421 	sctp_queue_purge_ulpevents(&sctp_sk(sk)->pd_lobby);
1422 
1423 	/* On a TCP-style socket, block for at most linger_time if set. */
1424 	if (sctp_style(sk, TCP) && timeout)
1425 		sctp_wait_for_close(sk, timeout);
1426 
1427 	/* This will run the backlog queue.  */
1428 	sctp_release_sock(sk);
1429 
1430 	/* Supposedly, no process has access to the socket, but
1431 	 * the net layers still may.
1432 	 */
1433 	sctp_local_bh_disable();
1434 	sctp_bh_lock_sock(sk);
1435 
1436 	/* Hold the sock, since sk_common_release() will put sock_put()
1437 	 * and we have just a little more cleanup.
1438 	 */
1439 	sock_hold(sk);
1440 	sk_common_release(sk);
1441 
1442 	sctp_bh_unlock_sock(sk);
1443 	sctp_local_bh_enable();
1444 
1445 	sock_put(sk);
1446 
1447 	SCTP_DBG_OBJCNT_DEC(sock);
1448 }
1449 
1450 /* Handle EPIPE error. */
sctp_error(struct sock * sk,int flags,int err)1451 static int sctp_error(struct sock *sk, int flags, int err)
1452 {
1453 	if (err == -EPIPE)
1454 		err = sock_error(sk) ? : -EPIPE;
1455 	if (err == -EPIPE && !(flags & MSG_NOSIGNAL))
1456 		send_sig(SIGPIPE, current, 0);
1457 	return err;
1458 }
1459 
1460 /* API 3.1.3 sendmsg() - UDP Style Syntax
1461  *
1462  * An application uses sendmsg() and recvmsg() calls to transmit data to
1463  * and receive data from its peer.
1464  *
1465  *  ssize_t sendmsg(int socket, const struct msghdr *message,
1466  *                  int flags);
1467  *
1468  *  socket  - the socket descriptor of the endpoint.
1469  *  message - pointer to the msghdr structure which contains a single
1470  *            user message and possibly some ancillary data.
1471  *
1472  *            See Section 5 for complete description of the data
1473  *            structures.
1474  *
1475  *  flags   - flags sent or received with the user message, see Section
1476  *            5 for complete description of the flags.
1477  *
1478  * Note:  This function could use a rewrite especially when explicit
1479  * connect support comes in.
1480  */
1481 /* BUG:  We do not implement the equivalent of sk_stream_wait_memory(). */
1482 
1483 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *, sctp_cmsgs_t *);
1484 
sctp_sendmsg(struct kiocb * iocb,struct sock * sk,struct msghdr * msg,size_t msg_len)1485 SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
1486 			     struct msghdr *msg, size_t msg_len)
1487 {
1488 	struct sctp_sock *sp;
1489 	struct sctp_endpoint *ep;
1490 	struct sctp_association *new_asoc=NULL, *asoc=NULL;
1491 	struct sctp_transport *transport, *chunk_tp;
1492 	struct sctp_chunk *chunk;
1493 	union sctp_addr to;
1494 	struct sockaddr *msg_name = NULL;
1495 	struct sctp_sndrcvinfo default_sinfo = { 0 };
1496 	struct sctp_sndrcvinfo *sinfo;
1497 	struct sctp_initmsg *sinit;
1498 	sctp_assoc_t associd = 0;
1499 	sctp_cmsgs_t cmsgs = { NULL };
1500 	int err;
1501 	sctp_scope_t scope;
1502 	long timeo;
1503 	__u16 sinfo_flags = 0;
1504 	struct sctp_datamsg *datamsg;
1505 	int msg_flags = msg->msg_flags;
1506 
1507 	SCTP_DEBUG_PRINTK("sctp_sendmsg(sk: %p, msg: %p, msg_len: %zu)\n",
1508 			  sk, msg, msg_len);
1509 
1510 	err = 0;
1511 	sp = sctp_sk(sk);
1512 	ep = sp->ep;
1513 
1514 	SCTP_DEBUG_PRINTK("Using endpoint: %p.\n", ep);
1515 
1516 	/* We cannot send a message over a TCP-style listening socket. */
1517 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) {
1518 		err = -EPIPE;
1519 		goto out_nounlock;
1520 	}
1521 
1522 	/* Parse out the SCTP CMSGs.  */
1523 	err = sctp_msghdr_parse(msg, &cmsgs);
1524 
1525 	if (err) {
1526 		SCTP_DEBUG_PRINTK("msghdr parse err = %x\n", err);
1527 		goto out_nounlock;
1528 	}
1529 
1530 	/* Fetch the destination address for this packet.  This
1531 	 * address only selects the association--it is not necessarily
1532 	 * the address we will send to.
1533 	 * For a peeled-off socket, msg_name is ignored.
1534 	 */
1535 	if (!sctp_style(sk, UDP_HIGH_BANDWIDTH) && msg->msg_name) {
1536 		int msg_namelen = msg->msg_namelen;
1537 
1538 		err = sctp_verify_addr(sk, (union sctp_addr *)msg->msg_name,
1539 				       msg_namelen);
1540 		if (err)
1541 			return err;
1542 
1543 		if (msg_namelen > sizeof(to))
1544 			msg_namelen = sizeof(to);
1545 		memcpy(&to, msg->msg_name, msg_namelen);
1546 		msg_name = msg->msg_name;
1547 	}
1548 
1549 	sinfo = cmsgs.info;
1550 	sinit = cmsgs.init;
1551 
1552 	/* Did the user specify SNDRCVINFO?  */
1553 	if (sinfo) {
1554 		sinfo_flags = sinfo->sinfo_flags;
1555 		associd = sinfo->sinfo_assoc_id;
1556 	}
1557 
1558 	SCTP_DEBUG_PRINTK("msg_len: %zu, sinfo_flags: 0x%x\n",
1559 			  msg_len, sinfo_flags);
1560 
1561 	/* SCTP_EOF or SCTP_ABORT cannot be set on a TCP-style socket. */
1562 	if (sctp_style(sk, TCP) && (sinfo_flags & (SCTP_EOF | SCTP_ABORT))) {
1563 		err = -EINVAL;
1564 		goto out_nounlock;
1565 	}
1566 
1567 	/* If SCTP_EOF is set, no data can be sent. Disallow sending zero
1568 	 * length messages when SCTP_EOF|SCTP_ABORT is not set.
1569 	 * If SCTP_ABORT is set, the message length could be non zero with
1570 	 * the msg_iov set to the user abort reason.
1571 	 */
1572 	if (((sinfo_flags & SCTP_EOF) && (msg_len > 0)) ||
1573 	    (!(sinfo_flags & (SCTP_EOF|SCTP_ABORT)) && (msg_len == 0))) {
1574 		err = -EINVAL;
1575 		goto out_nounlock;
1576 	}
1577 
1578 	/* If SCTP_ADDR_OVER is set, there must be an address
1579 	 * specified in msg_name.
1580 	 */
1581 	if ((sinfo_flags & SCTP_ADDR_OVER) && (!msg->msg_name)) {
1582 		err = -EINVAL;
1583 		goto out_nounlock;
1584 	}
1585 
1586 	transport = NULL;
1587 
1588 	SCTP_DEBUG_PRINTK("About to look up association.\n");
1589 
1590 	sctp_lock_sock(sk);
1591 
1592 	/* If a msg_name has been specified, assume this is to be used.  */
1593 	if (msg_name) {
1594 		/* Look for a matching association on the endpoint. */
1595 		asoc = sctp_endpoint_lookup_assoc(ep, &to, &transport);
1596 		if (!asoc) {
1597 			/* If we could not find a matching association on the
1598 			 * endpoint, make sure that it is not a TCP-style
1599 			 * socket that already has an association or there is
1600 			 * no peeled-off association on another socket.
1601 			 */
1602 			if ((sctp_style(sk, TCP) &&
1603 			     sctp_sstate(sk, ESTABLISHED)) ||
1604 			    sctp_endpoint_is_peeled_off(ep, &to)) {
1605 				err = -EADDRNOTAVAIL;
1606 				goto out_unlock;
1607 			}
1608 		}
1609 	} else {
1610 		asoc = sctp_id2assoc(sk, associd);
1611 		if (!asoc) {
1612 			err = -EPIPE;
1613 			goto out_unlock;
1614 		}
1615 	}
1616 
1617 	if (asoc) {
1618 		SCTP_DEBUG_PRINTK("Just looked up association: %p.\n", asoc);
1619 
1620 		/* We cannot send a message on a TCP-style SCTP_SS_ESTABLISHED
1621 		 * socket that has an association in CLOSED state. This can
1622 		 * happen when an accepted socket has an association that is
1623 		 * already CLOSED.
1624 		 */
1625 		if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP)) {
1626 			err = -EPIPE;
1627 			goto out_unlock;
1628 		}
1629 
1630 		if (sinfo_flags & SCTP_EOF) {
1631 			SCTP_DEBUG_PRINTK("Shutting down association: %p\n",
1632 					  asoc);
1633 			sctp_primitive_SHUTDOWN(asoc, NULL);
1634 			err = 0;
1635 			goto out_unlock;
1636 		}
1637 		if (sinfo_flags & SCTP_ABORT) {
1638 
1639 			chunk = sctp_make_abort_user(asoc, msg, msg_len);
1640 			if (!chunk) {
1641 				err = -ENOMEM;
1642 				goto out_unlock;
1643 			}
1644 
1645 			SCTP_DEBUG_PRINTK("Aborting association: %p\n", asoc);
1646 			sctp_primitive_ABORT(asoc, chunk);
1647 			err = 0;
1648 			goto out_unlock;
1649 		}
1650 	}
1651 
1652 	/* Do we need to create the association?  */
1653 	if (!asoc) {
1654 		SCTP_DEBUG_PRINTK("There is no association yet.\n");
1655 
1656 		if (sinfo_flags & (SCTP_EOF | SCTP_ABORT)) {
1657 			err = -EINVAL;
1658 			goto out_unlock;
1659 		}
1660 
1661 		/* Check for invalid stream against the stream counts,
1662 		 * either the default or the user specified stream counts.
1663 		 */
1664 		if (sinfo) {
1665 			if (!sinit || (sinit && !sinit->sinit_num_ostreams)) {
1666 				/* Check against the defaults. */
1667 				if (sinfo->sinfo_stream >=
1668 				    sp->initmsg.sinit_num_ostreams) {
1669 					err = -EINVAL;
1670 					goto out_unlock;
1671 				}
1672 			} else {
1673 				/* Check against the requested.  */
1674 				if (sinfo->sinfo_stream >=
1675 				    sinit->sinit_num_ostreams) {
1676 					err = -EINVAL;
1677 					goto out_unlock;
1678 				}
1679 			}
1680 		}
1681 
1682 		/*
1683 		 * API 3.1.2 bind() - UDP Style Syntax
1684 		 * If a bind() or sctp_bindx() is not called prior to a
1685 		 * sendmsg() call that initiates a new association, the
1686 		 * system picks an ephemeral port and will choose an address
1687 		 * set equivalent to binding with a wildcard address.
1688 		 */
1689 		if (!ep->base.bind_addr.port) {
1690 			if (sctp_autobind(sk)) {
1691 				err = -EAGAIN;
1692 				goto out_unlock;
1693 			}
1694 		} else {
1695 			/*
1696 			 * If an unprivileged user inherits a one-to-many
1697 			 * style socket with open associations on a privileged
1698 			 * port, it MAY be permitted to accept new associations,
1699 			 * but it SHOULD NOT be permitted to open new
1700 			 * associations.
1701 			 */
1702 			if (ep->base.bind_addr.port < PROT_SOCK &&
1703 			    !capable(CAP_NET_BIND_SERVICE)) {
1704 				err = -EACCES;
1705 				goto out_unlock;
1706 			}
1707 		}
1708 
1709 		scope = sctp_scope(&to);
1710 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
1711 		if (!new_asoc) {
1712 			err = -ENOMEM;
1713 			goto out_unlock;
1714 		}
1715 		asoc = new_asoc;
1716 		err = sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL);
1717 		if (err < 0) {
1718 			err = -ENOMEM;
1719 			goto out_free;
1720 		}
1721 
1722 		/* If the SCTP_INIT ancillary data is specified, set all
1723 		 * the association init values accordingly.
1724 		 */
1725 		if (sinit) {
1726 			if (sinit->sinit_num_ostreams) {
1727 				asoc->c.sinit_num_ostreams =
1728 					sinit->sinit_num_ostreams;
1729 			}
1730 			if (sinit->sinit_max_instreams) {
1731 				asoc->c.sinit_max_instreams =
1732 					sinit->sinit_max_instreams;
1733 			}
1734 			if (sinit->sinit_max_attempts) {
1735 				asoc->max_init_attempts
1736 					= sinit->sinit_max_attempts;
1737 			}
1738 			if (sinit->sinit_max_init_timeo) {
1739 				asoc->max_init_timeo =
1740 				 msecs_to_jiffies(sinit->sinit_max_init_timeo);
1741 			}
1742 		}
1743 
1744 		/* Prime the peer's transport structures.  */
1745 		transport = sctp_assoc_add_peer(asoc, &to, GFP_KERNEL, SCTP_UNKNOWN);
1746 		if (!transport) {
1747 			err = -ENOMEM;
1748 			goto out_free;
1749 		}
1750 	}
1751 
1752 	/* ASSERT: we have a valid association at this point.  */
1753 	SCTP_DEBUG_PRINTK("We have a valid association.\n");
1754 
1755 	if (!sinfo) {
1756 		/* If the user didn't specify SNDRCVINFO, make up one with
1757 		 * some defaults.
1758 		 */
1759 		default_sinfo.sinfo_stream = asoc->default_stream;
1760 		default_sinfo.sinfo_flags = asoc->default_flags;
1761 		default_sinfo.sinfo_ppid = asoc->default_ppid;
1762 		default_sinfo.sinfo_context = asoc->default_context;
1763 		default_sinfo.sinfo_timetolive = asoc->default_timetolive;
1764 		default_sinfo.sinfo_assoc_id = sctp_assoc2id(asoc);
1765 		sinfo = &default_sinfo;
1766 	}
1767 
1768 	/* API 7.1.7, the sndbuf size per association bounds the
1769 	 * maximum size of data that can be sent in a single send call.
1770 	 */
1771 	if (msg_len > sk->sk_sndbuf) {
1772 		err = -EMSGSIZE;
1773 		goto out_free;
1774 	}
1775 
1776 	if (asoc->pmtu_pending)
1777 		sctp_assoc_pending_pmtu(asoc);
1778 
1779 	/* If fragmentation is disabled and the message length exceeds the
1780 	 * association fragmentation point, return EMSGSIZE.  The I-D
1781 	 * does not specify what this error is, but this looks like
1782 	 * a great fit.
1783 	 */
1784 	if (sctp_sk(sk)->disable_fragments && (msg_len > asoc->frag_point)) {
1785 		err = -EMSGSIZE;
1786 		goto out_free;
1787 	}
1788 
1789 	if (sinfo) {
1790 		/* Check for invalid stream. */
1791 		if (sinfo->sinfo_stream >= asoc->c.sinit_num_ostreams) {
1792 			err = -EINVAL;
1793 			goto out_free;
1794 		}
1795 	}
1796 
1797 	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1798 	if (!sctp_wspace(asoc)) {
1799 		err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
1800 		if (err)
1801 			goto out_free;
1802 	}
1803 
1804 	/* If an address is passed with the sendto/sendmsg call, it is used
1805 	 * to override the primary destination address in the TCP model, or
1806 	 * when SCTP_ADDR_OVER flag is set in the UDP model.
1807 	 */
1808 	if ((sctp_style(sk, TCP) && msg_name) ||
1809 	    (sinfo_flags & SCTP_ADDR_OVER)) {
1810 		chunk_tp = sctp_assoc_lookup_paddr(asoc, &to);
1811 		if (!chunk_tp) {
1812 			err = -EINVAL;
1813 			goto out_free;
1814 		}
1815 	} else
1816 		chunk_tp = NULL;
1817 
1818 	/* Auto-connect, if we aren't connected already. */
1819 	if (sctp_state(asoc, CLOSED)) {
1820 		err = sctp_primitive_ASSOCIATE(asoc, NULL);
1821 		if (err < 0)
1822 			goto out_free;
1823 		SCTP_DEBUG_PRINTK("We associated primitively.\n");
1824 	}
1825 
1826 	/* Break the message into multiple chunks of maximum size. */
1827 	datamsg = sctp_datamsg_from_user(asoc, sinfo, msg, msg_len);
1828 	if (!datamsg) {
1829 		err = -ENOMEM;
1830 		goto out_free;
1831 	}
1832 
1833 	/* Now send the (possibly) fragmented message. */
1834 	list_for_each_entry(chunk, &datamsg->chunks, frag_list) {
1835 		sctp_chunk_hold(chunk);
1836 
1837 		/* Do accounting for the write space.  */
1838 		sctp_set_owner_w(chunk);
1839 
1840 		chunk->transport = chunk_tp;
1841 	}
1842 
1843 	/* Send it to the lower layers.  Note:  all chunks
1844 	 * must either fail or succeed.   The lower layer
1845 	 * works that way today.  Keep it that way or this
1846 	 * breaks.
1847 	 */
1848 	err = sctp_primitive_SEND(asoc, datamsg);
1849 	/* Did the lower layer accept the chunk? */
1850 	if (err)
1851 		sctp_datamsg_free(datamsg);
1852 	else
1853 		sctp_datamsg_put(datamsg);
1854 
1855 	SCTP_DEBUG_PRINTK("We sent primitively.\n");
1856 
1857 	if (err)
1858 		goto out_free;
1859 	else
1860 		err = msg_len;
1861 
1862 	/* If we are already past ASSOCIATE, the lower
1863 	 * layers are responsible for association cleanup.
1864 	 */
1865 	goto out_unlock;
1866 
1867 out_free:
1868 	if (new_asoc)
1869 		sctp_association_free(asoc);
1870 out_unlock:
1871 	sctp_release_sock(sk);
1872 
1873 out_nounlock:
1874 	return sctp_error(sk, msg_flags, err);
1875 
1876 #if 0
1877 do_sock_err:
1878 	if (msg_len)
1879 		err = msg_len;
1880 	else
1881 		err = sock_error(sk);
1882 	goto out;
1883 
1884 do_interrupted:
1885 	if (msg_len)
1886 		err = msg_len;
1887 	goto out;
1888 #endif /* 0 */
1889 }
1890 
1891 /* This is an extended version of skb_pull() that removes the data from the
1892  * start of a skb even when data is spread across the list of skb's in the
1893  * frag_list. len specifies the total amount of data that needs to be removed.
1894  * when 'len' bytes could be removed from the skb, it returns 0.
1895  * If 'len' exceeds the total skb length,  it returns the no. of bytes that
1896  * could not be removed.
1897  */
sctp_skb_pull(struct sk_buff * skb,int len)1898 static int sctp_skb_pull(struct sk_buff *skb, int len)
1899 {
1900 	struct sk_buff *list;
1901 	int skb_len = skb_headlen(skb);
1902 	int rlen;
1903 
1904 	if (len <= skb_len) {
1905 		__skb_pull(skb, len);
1906 		return 0;
1907 	}
1908 	len -= skb_len;
1909 	__skb_pull(skb, skb_len);
1910 
1911 	skb_walk_frags(skb, list) {
1912 		rlen = sctp_skb_pull(list, len);
1913 		skb->len -= (len-rlen);
1914 		skb->data_len -= (len-rlen);
1915 
1916 		if (!rlen)
1917 			return 0;
1918 
1919 		len = rlen;
1920 	}
1921 
1922 	return len;
1923 }
1924 
1925 /* API 3.1.3  recvmsg() - UDP Style Syntax
1926  *
1927  *  ssize_t recvmsg(int socket, struct msghdr *message,
1928  *                    int flags);
1929  *
1930  *  socket  - the socket descriptor of the endpoint.
1931  *  message - pointer to the msghdr structure which contains a single
1932  *            user message and possibly some ancillary data.
1933  *
1934  *            See Section 5 for complete description of the data
1935  *            structures.
1936  *
1937  *  flags   - flags sent or received with the user message, see Section
1938  *            5 for complete description of the flags.
1939  */
1940 static struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);
1941 
sctp_recvmsg(struct kiocb * iocb,struct sock * sk,struct msghdr * msg,size_t len,int noblock,int flags,int * addr_len)1942 SCTP_STATIC int sctp_recvmsg(struct kiocb *iocb, struct sock *sk,
1943 			     struct msghdr *msg, size_t len, int noblock,
1944 			     int flags, int *addr_len)
1945 {
1946 	struct sctp_ulpevent *event = NULL;
1947 	struct sctp_sock *sp = sctp_sk(sk);
1948 	struct sk_buff *skb;
1949 	int copied;
1950 	int err = 0;
1951 	int skb_len;
1952 
1953 	SCTP_DEBUG_PRINTK("sctp_recvmsg(%s: %p, %s: %p, %s: %zd, %s: %d, %s: "
1954 			  "0x%x, %s: %p)\n", "sk", sk, "msghdr", msg,
1955 			  "len", len, "knoblauch", noblock,
1956 			  "flags", flags, "addr_len", addr_len);
1957 
1958 	sctp_lock_sock(sk);
1959 
1960 	if (sctp_style(sk, TCP) && !sctp_sstate(sk, ESTABLISHED)) {
1961 		err = -ENOTCONN;
1962 		goto out;
1963 	}
1964 
1965 	skb = sctp_skb_recv_datagram(sk, flags, noblock, &err);
1966 	if (!skb)
1967 		goto out;
1968 
1969 	/* Get the total length of the skb including any skb's in the
1970 	 * frag_list.
1971 	 */
1972 	skb_len = skb->len;
1973 
1974 	copied = skb_len;
1975 	if (copied > len)
1976 		copied = len;
1977 
1978 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1979 
1980 	event = sctp_skb2event(skb);
1981 
1982 	if (err)
1983 		goto out_free;
1984 
1985 	sock_recv_ts_and_drops(msg, sk, skb);
1986 	if (sctp_ulpevent_is_notification(event)) {
1987 		msg->msg_flags |= MSG_NOTIFICATION;
1988 		sp->pf->event_msgname(event, msg->msg_name, addr_len);
1989 	} else {
1990 		sp->pf->skb_msgname(skb, msg->msg_name, addr_len);
1991 	}
1992 
1993 	/* Check if we allow SCTP_SNDRCVINFO. */
1994 	if (sp->subscribe.sctp_data_io_event)
1995 		sctp_ulpevent_read_sndrcvinfo(event, msg);
1996 #if 0
1997 	/* FIXME: we should be calling IP/IPv6 layers.  */
1998 	if (sk->sk_protinfo.af_inet.cmsg_flags)
1999 		ip_cmsg_recv(msg, skb);
2000 #endif
2001 
2002 	err = copied;
2003 
2004 	/* If skb's length exceeds the user's buffer, update the skb and
2005 	 * push it back to the receive_queue so that the next call to
2006 	 * recvmsg() will return the remaining data. Don't set MSG_EOR.
2007 	 */
2008 	if (skb_len > copied) {
2009 		msg->msg_flags &= ~MSG_EOR;
2010 		if (flags & MSG_PEEK)
2011 			goto out_free;
2012 		sctp_skb_pull(skb, copied);
2013 		skb_queue_head(&sk->sk_receive_queue, skb);
2014 
2015 		/* When only partial message is copied to the user, increase
2016 		 * rwnd by that amount. If all the data in the skb is read,
2017 		 * rwnd is updated when the event is freed.
2018 		 */
2019 		if (!sctp_ulpevent_is_notification(event))
2020 			sctp_assoc_rwnd_increase(event->asoc, copied);
2021 		goto out;
2022 	} else if ((event->msg_flags & MSG_NOTIFICATION) ||
2023 		   (event->msg_flags & MSG_EOR))
2024 		msg->msg_flags |= MSG_EOR;
2025 	else
2026 		msg->msg_flags &= ~MSG_EOR;
2027 
2028 out_free:
2029 	if (flags & MSG_PEEK) {
2030 		/* Release the skb reference acquired after peeking the skb in
2031 		 * sctp_skb_recv_datagram().
2032 		 */
2033 		kfree_skb(skb);
2034 	} else {
2035 		/* Free the event which includes releasing the reference to
2036 		 * the owner of the skb, freeing the skb and updating the
2037 		 * rwnd.
2038 		 */
2039 		sctp_ulpevent_free(event);
2040 	}
2041 out:
2042 	sctp_release_sock(sk);
2043 	return err;
2044 }
2045 
2046 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
2047  *
2048  * This option is a on/off flag.  If enabled no SCTP message
2049  * fragmentation will be performed.  Instead if a message being sent
2050  * exceeds the current PMTU size, the message will NOT be sent and
2051  * instead a error will be indicated to the user.
2052  */
sctp_setsockopt_disable_fragments(struct sock * sk,char __user * optval,unsigned int optlen)2053 static int sctp_setsockopt_disable_fragments(struct sock *sk,
2054 					     char __user *optval,
2055 					     unsigned int optlen)
2056 {
2057 	int val;
2058 
2059 	if (optlen < sizeof(int))
2060 		return -EINVAL;
2061 
2062 	if (get_user(val, (int __user *)optval))
2063 		return -EFAULT;
2064 
2065 	sctp_sk(sk)->disable_fragments = (val == 0) ? 0 : 1;
2066 
2067 	return 0;
2068 }
2069 
sctp_setsockopt_events(struct sock * sk,char __user * optval,unsigned int optlen)2070 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
2071 				  unsigned int optlen)
2072 {
2073 	if (optlen > sizeof(struct sctp_event_subscribe))
2074 		return -EINVAL;
2075 	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
2076 		return -EFAULT;
2077 	return 0;
2078 }
2079 
2080 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
2081  *
2082  * This socket option is applicable to the UDP-style socket only.  When
2083  * set it will cause associations that are idle for more than the
2084  * specified number of seconds to automatically close.  An association
2085  * being idle is defined an association that has NOT sent or received
2086  * user data.  The special value of '0' indicates that no automatic
2087  * close of any associations should be performed.  The option expects an
2088  * integer defining the number of seconds of idle time before an
2089  * association is closed.
2090  */
sctp_setsockopt_autoclose(struct sock * sk,char __user * optval,unsigned int optlen)2091 static int sctp_setsockopt_autoclose(struct sock *sk, char __user *optval,
2092 				     unsigned int optlen)
2093 {
2094 	struct sctp_sock *sp = sctp_sk(sk);
2095 
2096 	/* Applicable to UDP-style socket only */
2097 	if (sctp_style(sk, TCP))
2098 		return -EOPNOTSUPP;
2099 	if (optlen != sizeof(int))
2100 		return -EINVAL;
2101 	if (copy_from_user(&sp->autoclose, optval, optlen))
2102 		return -EFAULT;
2103 	/* make sure it won't exceed MAX_SCHEDULE_TIMEOUT */
2104 	sp->autoclose = min_t(long, sp->autoclose, MAX_SCHEDULE_TIMEOUT / HZ);
2105 
2106 	return 0;
2107 }
2108 
2109 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
2110  *
2111  * Applications can enable or disable heartbeats for any peer address of
2112  * an association, modify an address's heartbeat interval, force a
2113  * heartbeat to be sent immediately, and adjust the address's maximum
2114  * number of retransmissions sent before an address is considered
2115  * unreachable.  The following structure is used to access and modify an
2116  * address's parameters:
2117  *
2118  *  struct sctp_paddrparams {
2119  *     sctp_assoc_t            spp_assoc_id;
2120  *     struct sockaddr_storage spp_address;
2121  *     uint32_t                spp_hbinterval;
2122  *     uint16_t                spp_pathmaxrxt;
2123  *     uint32_t                spp_pathmtu;
2124  *     uint32_t                spp_sackdelay;
2125  *     uint32_t                spp_flags;
2126  * };
2127  *
2128  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
2129  *                     application, and identifies the association for
2130  *                     this query.
2131  *   spp_address     - This specifies which address is of interest.
2132  *   spp_hbinterval  - This contains the value of the heartbeat interval,
2133  *                     in milliseconds.  If a  value of zero
2134  *                     is present in this field then no changes are to
2135  *                     be made to this parameter.
2136  *   spp_pathmaxrxt  - This contains the maximum number of
2137  *                     retransmissions before this address shall be
2138  *                     considered unreachable. If a  value of zero
2139  *                     is present in this field then no changes are to
2140  *                     be made to this parameter.
2141  *   spp_pathmtu     - When Path MTU discovery is disabled the value
2142  *                     specified here will be the "fixed" path mtu.
2143  *                     Note that if the spp_address field is empty
2144  *                     then all associations on this address will
2145  *                     have this fixed path mtu set upon them.
2146  *
2147  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
2148  *                     the number of milliseconds that sacks will be delayed
2149  *                     for. This value will apply to all addresses of an
2150  *                     association if the spp_address field is empty. Note
2151  *                     also, that if delayed sack is enabled and this
2152  *                     value is set to 0, no change is made to the last
2153  *                     recorded delayed sack timer value.
2154  *
2155  *   spp_flags       - These flags are used to control various features
2156  *                     on an association. The flag field may contain
2157  *                     zero or more of the following options.
2158  *
2159  *                     SPP_HB_ENABLE  - Enable heartbeats on the
2160  *                     specified address. Note that if the address
2161  *                     field is empty all addresses for the association
2162  *                     have heartbeats enabled upon them.
2163  *
2164  *                     SPP_HB_DISABLE - Disable heartbeats on the
2165  *                     speicifed address. Note that if the address
2166  *                     field is empty all addresses for the association
2167  *                     will have their heartbeats disabled. Note also
2168  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
2169  *                     mutually exclusive, only one of these two should
2170  *                     be specified. Enabling both fields will have
2171  *                     undetermined results.
2172  *
2173  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
2174  *                     to be made immediately.
2175  *
2176  *                     SPP_HB_TIME_IS_ZERO - Specify's that the time for
2177  *                     heartbeat delayis to be set to the value of 0
2178  *                     milliseconds.
2179  *
2180  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
2181  *                     discovery upon the specified address. Note that
2182  *                     if the address feild is empty then all addresses
2183  *                     on the association are effected.
2184  *
2185  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
2186  *                     discovery upon the specified address. Note that
2187  *                     if the address feild is empty then all addresses
2188  *                     on the association are effected. Not also that
2189  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
2190  *                     exclusive. Enabling both will have undetermined
2191  *                     results.
2192  *
2193  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
2194  *                     on delayed sack. The time specified in spp_sackdelay
2195  *                     is used to specify the sack delay for this address. Note
2196  *                     that if spp_address is empty then all addresses will
2197  *                     enable delayed sack and take on the sack delay
2198  *                     value specified in spp_sackdelay.
2199  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
2200  *                     off delayed sack. If the spp_address field is blank then
2201  *                     delayed sack is disabled for the entire association. Note
2202  *                     also that this field is mutually exclusive to
2203  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
2204  *                     results.
2205  */
sctp_apply_peer_addr_params(struct sctp_paddrparams * params,struct sctp_transport * trans,struct sctp_association * asoc,struct sctp_sock * sp,int hb_change,int pmtud_change,int sackdelay_change)2206 static int sctp_apply_peer_addr_params(struct sctp_paddrparams *params,
2207 				       struct sctp_transport   *trans,
2208 				       struct sctp_association *asoc,
2209 				       struct sctp_sock        *sp,
2210 				       int                      hb_change,
2211 				       int                      pmtud_change,
2212 				       int                      sackdelay_change)
2213 {
2214 	int error;
2215 
2216 	if (params->spp_flags & SPP_HB_DEMAND && trans) {
2217 		error = sctp_primitive_REQUESTHEARTBEAT (trans->asoc, trans);
2218 		if (error)
2219 			return error;
2220 	}
2221 
2222 	/* Note that unless the spp_flag is set to SPP_HB_ENABLE the value of
2223 	 * this field is ignored.  Note also that a value of zero indicates
2224 	 * the current setting should be left unchanged.
2225 	 */
2226 	if (params->spp_flags & SPP_HB_ENABLE) {
2227 
2228 		/* Re-zero the interval if the SPP_HB_TIME_IS_ZERO is
2229 		 * set.  This lets us use 0 value when this flag
2230 		 * is set.
2231 		 */
2232 		if (params->spp_flags & SPP_HB_TIME_IS_ZERO)
2233 			params->spp_hbinterval = 0;
2234 
2235 		if (params->spp_hbinterval ||
2236 		    (params->spp_flags & SPP_HB_TIME_IS_ZERO)) {
2237 			if (trans) {
2238 				trans->hbinterval =
2239 				    msecs_to_jiffies(params->spp_hbinterval);
2240 			} else if (asoc) {
2241 				asoc->hbinterval =
2242 				    msecs_to_jiffies(params->spp_hbinterval);
2243 			} else {
2244 				sp->hbinterval = params->spp_hbinterval;
2245 			}
2246 		}
2247 	}
2248 
2249 	if (hb_change) {
2250 		if (trans) {
2251 			trans->param_flags =
2252 				(trans->param_flags & ~SPP_HB) | hb_change;
2253 		} else if (asoc) {
2254 			asoc->param_flags =
2255 				(asoc->param_flags & ~SPP_HB) | hb_change;
2256 		} else {
2257 			sp->param_flags =
2258 				(sp->param_flags & ~SPP_HB) | hb_change;
2259 		}
2260 	}
2261 
2262 	/* When Path MTU discovery is disabled the value specified here will
2263 	 * be the "fixed" path mtu (i.e. the value of the spp_flags field must
2264 	 * include the flag SPP_PMTUD_DISABLE for this field to have any
2265 	 * effect).
2266 	 */
2267 	if ((params->spp_flags & SPP_PMTUD_DISABLE) && params->spp_pathmtu) {
2268 		if (trans) {
2269 			trans->pathmtu = params->spp_pathmtu;
2270 			sctp_assoc_sync_pmtu(asoc);
2271 		} else if (asoc) {
2272 			asoc->pathmtu = params->spp_pathmtu;
2273 			sctp_frag_point(asoc, params->spp_pathmtu);
2274 		} else {
2275 			sp->pathmtu = params->spp_pathmtu;
2276 		}
2277 	}
2278 
2279 	if (pmtud_change) {
2280 		if (trans) {
2281 			int update = (trans->param_flags & SPP_PMTUD_DISABLE) &&
2282 				(params->spp_flags & SPP_PMTUD_ENABLE);
2283 			trans->param_flags =
2284 				(trans->param_flags & ~SPP_PMTUD) | pmtud_change;
2285 			if (update) {
2286 				sctp_transport_pmtu(trans);
2287 				sctp_assoc_sync_pmtu(asoc);
2288 			}
2289 		} else if (asoc) {
2290 			asoc->param_flags =
2291 				(asoc->param_flags & ~SPP_PMTUD) | pmtud_change;
2292 		} else {
2293 			sp->param_flags =
2294 				(sp->param_flags & ~SPP_PMTUD) | pmtud_change;
2295 		}
2296 	}
2297 
2298 	/* Note that unless the spp_flag is set to SPP_SACKDELAY_ENABLE the
2299 	 * value of this field is ignored.  Note also that a value of zero
2300 	 * indicates the current setting should be left unchanged.
2301 	 */
2302 	if ((params->spp_flags & SPP_SACKDELAY_ENABLE) && params->spp_sackdelay) {
2303 		if (trans) {
2304 			trans->sackdelay =
2305 				msecs_to_jiffies(params->spp_sackdelay);
2306 		} else if (asoc) {
2307 			asoc->sackdelay =
2308 				msecs_to_jiffies(params->spp_sackdelay);
2309 		} else {
2310 			sp->sackdelay = params->spp_sackdelay;
2311 		}
2312 	}
2313 
2314 	if (sackdelay_change) {
2315 		if (trans) {
2316 			trans->param_flags =
2317 				(trans->param_flags & ~SPP_SACKDELAY) |
2318 				sackdelay_change;
2319 		} else if (asoc) {
2320 			asoc->param_flags =
2321 				(asoc->param_flags & ~SPP_SACKDELAY) |
2322 				sackdelay_change;
2323 		} else {
2324 			sp->param_flags =
2325 				(sp->param_flags & ~SPP_SACKDELAY) |
2326 				sackdelay_change;
2327 		}
2328 	}
2329 
2330 	/* Note that a value of zero indicates the current setting should be
2331 	   left unchanged.
2332 	 */
2333 	if (params->spp_pathmaxrxt) {
2334 		if (trans) {
2335 			trans->pathmaxrxt = params->spp_pathmaxrxt;
2336 		} else if (asoc) {
2337 			asoc->pathmaxrxt = params->spp_pathmaxrxt;
2338 		} else {
2339 			sp->pathmaxrxt = params->spp_pathmaxrxt;
2340 		}
2341 	}
2342 
2343 	return 0;
2344 }
2345 
sctp_setsockopt_peer_addr_params(struct sock * sk,char __user * optval,unsigned int optlen)2346 static int sctp_setsockopt_peer_addr_params(struct sock *sk,
2347 					    char __user *optval,
2348 					    unsigned int optlen)
2349 {
2350 	struct sctp_paddrparams  params;
2351 	struct sctp_transport   *trans = NULL;
2352 	struct sctp_association *asoc = NULL;
2353 	struct sctp_sock        *sp = sctp_sk(sk);
2354 	int error;
2355 	int hb_change, pmtud_change, sackdelay_change;
2356 
2357 	if (optlen != sizeof(struct sctp_paddrparams))
2358 		return - EINVAL;
2359 
2360 	if (copy_from_user(&params, optval, optlen))
2361 		return -EFAULT;
2362 
2363 	/* Validate flags and value parameters. */
2364 	hb_change        = params.spp_flags & SPP_HB;
2365 	pmtud_change     = params.spp_flags & SPP_PMTUD;
2366 	sackdelay_change = params.spp_flags & SPP_SACKDELAY;
2367 
2368 	if (hb_change        == SPP_HB ||
2369 	    pmtud_change     == SPP_PMTUD ||
2370 	    sackdelay_change == SPP_SACKDELAY ||
2371 	    params.spp_sackdelay > 500 ||
2372 	    (params.spp_pathmtu &&
2373 	     params.spp_pathmtu < SCTP_DEFAULT_MINSEGMENT))
2374 		return -EINVAL;
2375 
2376 	/* If an address other than INADDR_ANY is specified, and
2377 	 * no transport is found, then the request is invalid.
2378 	 */
2379 	if (!sctp_is_any(sk, ( union sctp_addr *)&params.spp_address)) {
2380 		trans = sctp_addr_id2transport(sk, &params.spp_address,
2381 					       params.spp_assoc_id);
2382 		if (!trans)
2383 			return -EINVAL;
2384 	}
2385 
2386 	/* Get association, if assoc_id != 0 and the socket is a one
2387 	 * to many style socket, and an association was not found, then
2388 	 * the id was invalid.
2389 	 */
2390 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
2391 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP))
2392 		return -EINVAL;
2393 
2394 	/* Heartbeat demand can only be sent on a transport or
2395 	 * association, but not a socket.
2396 	 */
2397 	if (params.spp_flags & SPP_HB_DEMAND && !trans && !asoc)
2398 		return -EINVAL;
2399 
2400 	/* Process parameters. */
2401 	error = sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2402 					    hb_change, pmtud_change,
2403 					    sackdelay_change);
2404 
2405 	if (error)
2406 		return error;
2407 
2408 	/* If changes are for association, also apply parameters to each
2409 	 * transport.
2410 	 */
2411 	if (!trans && asoc) {
2412 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2413 				transports) {
2414 			sctp_apply_peer_addr_params(&params, trans, asoc, sp,
2415 						    hb_change, pmtud_change,
2416 						    sackdelay_change);
2417 		}
2418 	}
2419 
2420 	return 0;
2421 }
2422 
2423 /*
2424  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
2425  *
2426  * This option will effect the way delayed acks are performed.  This
2427  * option allows you to get or set the delayed ack time, in
2428  * milliseconds.  It also allows changing the delayed ack frequency.
2429  * Changing the frequency to 1 disables the delayed sack algorithm.  If
2430  * the assoc_id is 0, then this sets or gets the endpoints default
2431  * values.  If the assoc_id field is non-zero, then the set or get
2432  * effects the specified association for the one to many model (the
2433  * assoc_id field is ignored by the one to one model).  Note that if
2434  * sack_delay or sack_freq are 0 when setting this option, then the
2435  * current values will remain unchanged.
2436  *
2437  * struct sctp_sack_info {
2438  *     sctp_assoc_t            sack_assoc_id;
2439  *     uint32_t                sack_delay;
2440  *     uint32_t                sack_freq;
2441  * };
2442  *
2443  * sack_assoc_id -  This parameter, indicates which association the user
2444  *    is performing an action upon.  Note that if this field's value is
2445  *    zero then the endpoints default value is changed (effecting future
2446  *    associations only).
2447  *
2448  * sack_delay -  This parameter contains the number of milliseconds that
2449  *    the user is requesting the delayed ACK timer be set to.  Note that
2450  *    this value is defined in the standard to be between 200 and 500
2451  *    milliseconds.
2452  *
2453  * sack_freq -  This parameter contains the number of packets that must
2454  *    be received before a sack is sent without waiting for the delay
2455  *    timer to expire.  The default value for this is 2, setting this
2456  *    value to 1 will disable the delayed sack algorithm.
2457  */
2458 
sctp_setsockopt_delayed_ack(struct sock * sk,char __user * optval,unsigned int optlen)2459 static int sctp_setsockopt_delayed_ack(struct sock *sk,
2460 				       char __user *optval, unsigned int optlen)
2461 {
2462 	struct sctp_sack_info    params;
2463 	struct sctp_transport   *trans = NULL;
2464 	struct sctp_association *asoc = NULL;
2465 	struct sctp_sock        *sp = sctp_sk(sk);
2466 
2467 	if (optlen == sizeof(struct sctp_sack_info)) {
2468 		if (copy_from_user(&params, optval, optlen))
2469 			return -EFAULT;
2470 
2471 		if (params.sack_delay == 0 && params.sack_freq == 0)
2472 			return 0;
2473 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
2474 		pr_warn("Use of struct sctp_assoc_value in delayed_ack socket option deprecated\n");
2475 		pr_warn("Use struct sctp_sack_info instead\n");
2476 		if (copy_from_user(&params, optval, optlen))
2477 			return -EFAULT;
2478 
2479 		if (params.sack_delay == 0)
2480 			params.sack_freq = 1;
2481 		else
2482 			params.sack_freq = 0;
2483 	} else
2484 		return - EINVAL;
2485 
2486 	/* Validate value parameter. */
2487 	if (params.sack_delay > 500)
2488 		return -EINVAL;
2489 
2490 	/* Get association, if sack_assoc_id != 0 and the socket is a one
2491 	 * to many style socket, and an association was not found, then
2492 	 * the id was invalid.
2493 	 */
2494 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
2495 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
2496 		return -EINVAL;
2497 
2498 	if (params.sack_delay) {
2499 		if (asoc) {
2500 			asoc->sackdelay =
2501 				msecs_to_jiffies(params.sack_delay);
2502 			asoc->param_flags =
2503 				(asoc->param_flags & ~SPP_SACKDELAY) |
2504 				SPP_SACKDELAY_ENABLE;
2505 		} else {
2506 			sp->sackdelay = params.sack_delay;
2507 			sp->param_flags =
2508 				(sp->param_flags & ~SPP_SACKDELAY) |
2509 				SPP_SACKDELAY_ENABLE;
2510 		}
2511 	}
2512 
2513 	if (params.sack_freq == 1) {
2514 		if (asoc) {
2515 			asoc->param_flags =
2516 				(asoc->param_flags & ~SPP_SACKDELAY) |
2517 				SPP_SACKDELAY_DISABLE;
2518 		} else {
2519 			sp->param_flags =
2520 				(sp->param_flags & ~SPP_SACKDELAY) |
2521 				SPP_SACKDELAY_DISABLE;
2522 		}
2523 	} else if (params.sack_freq > 1) {
2524 		if (asoc) {
2525 			asoc->sackfreq = params.sack_freq;
2526 			asoc->param_flags =
2527 				(asoc->param_flags & ~SPP_SACKDELAY) |
2528 				SPP_SACKDELAY_ENABLE;
2529 		} else {
2530 			sp->sackfreq = params.sack_freq;
2531 			sp->param_flags =
2532 				(sp->param_flags & ~SPP_SACKDELAY) |
2533 				SPP_SACKDELAY_ENABLE;
2534 		}
2535 	}
2536 
2537 	/* If change is for association, also apply to each transport. */
2538 	if (asoc) {
2539 		list_for_each_entry(trans, &asoc->peer.transport_addr_list,
2540 				transports) {
2541 			if (params.sack_delay) {
2542 				trans->sackdelay =
2543 					msecs_to_jiffies(params.sack_delay);
2544 				trans->param_flags =
2545 					(trans->param_flags & ~SPP_SACKDELAY) |
2546 					SPP_SACKDELAY_ENABLE;
2547 			}
2548 			if (params.sack_freq == 1) {
2549 				trans->param_flags =
2550 					(trans->param_flags & ~SPP_SACKDELAY) |
2551 					SPP_SACKDELAY_DISABLE;
2552 			} else if (params.sack_freq > 1) {
2553 				trans->sackfreq = params.sack_freq;
2554 				trans->param_flags =
2555 					(trans->param_flags & ~SPP_SACKDELAY) |
2556 					SPP_SACKDELAY_ENABLE;
2557 			}
2558 		}
2559 	}
2560 
2561 	return 0;
2562 }
2563 
2564 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
2565  *
2566  * Applications can specify protocol parameters for the default association
2567  * initialization.  The option name argument to setsockopt() and getsockopt()
2568  * is SCTP_INITMSG.
2569  *
2570  * Setting initialization parameters is effective only on an unconnected
2571  * socket (for UDP-style sockets only future associations are effected
2572  * by the change).  With TCP-style sockets, this option is inherited by
2573  * sockets derived from a listener socket.
2574  */
sctp_setsockopt_initmsg(struct sock * sk,char __user * optval,unsigned int optlen)2575 static int sctp_setsockopt_initmsg(struct sock *sk, char __user *optval, unsigned int optlen)
2576 {
2577 	struct sctp_initmsg sinit;
2578 	struct sctp_sock *sp = sctp_sk(sk);
2579 
2580 	if (optlen != sizeof(struct sctp_initmsg))
2581 		return -EINVAL;
2582 	if (copy_from_user(&sinit, optval, optlen))
2583 		return -EFAULT;
2584 
2585 	if (sinit.sinit_num_ostreams)
2586 		sp->initmsg.sinit_num_ostreams = sinit.sinit_num_ostreams;
2587 	if (sinit.sinit_max_instreams)
2588 		sp->initmsg.sinit_max_instreams = sinit.sinit_max_instreams;
2589 	if (sinit.sinit_max_attempts)
2590 		sp->initmsg.sinit_max_attempts = sinit.sinit_max_attempts;
2591 	if (sinit.sinit_max_init_timeo)
2592 		sp->initmsg.sinit_max_init_timeo = sinit.sinit_max_init_timeo;
2593 
2594 	return 0;
2595 }
2596 
2597 /*
2598  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
2599  *
2600  *   Applications that wish to use the sendto() system call may wish to
2601  *   specify a default set of parameters that would normally be supplied
2602  *   through the inclusion of ancillary data.  This socket option allows
2603  *   such an application to set the default sctp_sndrcvinfo structure.
2604  *   The application that wishes to use this socket option simply passes
2605  *   in to this call the sctp_sndrcvinfo structure defined in Section
2606  *   5.2.2) The input parameters accepted by this call include
2607  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
2608  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
2609  *   to this call if the caller is using the UDP model.
2610  */
sctp_setsockopt_default_send_param(struct sock * sk,char __user * optval,unsigned int optlen)2611 static int sctp_setsockopt_default_send_param(struct sock *sk,
2612 					      char __user *optval,
2613 					      unsigned int optlen)
2614 {
2615 	struct sctp_sndrcvinfo info;
2616 	struct sctp_association *asoc;
2617 	struct sctp_sock *sp = sctp_sk(sk);
2618 
2619 	if (optlen != sizeof(struct sctp_sndrcvinfo))
2620 		return -EINVAL;
2621 	if (copy_from_user(&info, optval, optlen))
2622 		return -EFAULT;
2623 
2624 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
2625 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
2626 		return -EINVAL;
2627 
2628 	if (asoc) {
2629 		asoc->default_stream = info.sinfo_stream;
2630 		asoc->default_flags = info.sinfo_flags;
2631 		asoc->default_ppid = info.sinfo_ppid;
2632 		asoc->default_context = info.sinfo_context;
2633 		asoc->default_timetolive = info.sinfo_timetolive;
2634 	} else {
2635 		sp->default_stream = info.sinfo_stream;
2636 		sp->default_flags = info.sinfo_flags;
2637 		sp->default_ppid = info.sinfo_ppid;
2638 		sp->default_context = info.sinfo_context;
2639 		sp->default_timetolive = info.sinfo_timetolive;
2640 	}
2641 
2642 	return 0;
2643 }
2644 
2645 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
2646  *
2647  * Requests that the local SCTP stack use the enclosed peer address as
2648  * the association primary.  The enclosed address must be one of the
2649  * association peer's addresses.
2650  */
sctp_setsockopt_primary_addr(struct sock * sk,char __user * optval,unsigned int optlen)2651 static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
2652 					unsigned int optlen)
2653 {
2654 	struct sctp_prim prim;
2655 	struct sctp_transport *trans;
2656 
2657 	if (optlen != sizeof(struct sctp_prim))
2658 		return -EINVAL;
2659 
2660 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
2661 		return -EFAULT;
2662 
2663 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
2664 	if (!trans)
2665 		return -EINVAL;
2666 
2667 	sctp_assoc_set_primary(trans->asoc, trans);
2668 
2669 	return 0;
2670 }
2671 
2672 /*
2673  * 7.1.5 SCTP_NODELAY
2674  *
2675  * Turn on/off any Nagle-like algorithm.  This means that packets are
2676  * generally sent as soon as possible and no unnecessary delays are
2677  * introduced, at the cost of more packets in the network.  Expects an
2678  *  integer boolean flag.
2679  */
sctp_setsockopt_nodelay(struct sock * sk,char __user * optval,unsigned int optlen)2680 static int sctp_setsockopt_nodelay(struct sock *sk, char __user *optval,
2681 				   unsigned int optlen)
2682 {
2683 	int val;
2684 
2685 	if (optlen < sizeof(int))
2686 		return -EINVAL;
2687 	if (get_user(val, (int __user *)optval))
2688 		return -EFAULT;
2689 
2690 	sctp_sk(sk)->nodelay = (val == 0) ? 0 : 1;
2691 	return 0;
2692 }
2693 
2694 /*
2695  *
2696  * 7.1.1 SCTP_RTOINFO
2697  *
2698  * The protocol parameters used to initialize and bound retransmission
2699  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
2700  * and modify these parameters.
2701  * All parameters are time values, in milliseconds.  A value of 0, when
2702  * modifying the parameters, indicates that the current value should not
2703  * be changed.
2704  *
2705  */
sctp_setsockopt_rtoinfo(struct sock * sk,char __user * optval,unsigned int optlen)2706 static int sctp_setsockopt_rtoinfo(struct sock *sk, char __user *optval, unsigned int optlen)
2707 {
2708 	struct sctp_rtoinfo rtoinfo;
2709 	struct sctp_association *asoc;
2710 
2711 	if (optlen != sizeof (struct sctp_rtoinfo))
2712 		return -EINVAL;
2713 
2714 	if (copy_from_user(&rtoinfo, optval, optlen))
2715 		return -EFAULT;
2716 
2717 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
2718 
2719 	/* Set the values to the specific association */
2720 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
2721 		return -EINVAL;
2722 
2723 	if (asoc) {
2724 		if (rtoinfo.srto_initial != 0)
2725 			asoc->rto_initial =
2726 				msecs_to_jiffies(rtoinfo.srto_initial);
2727 		if (rtoinfo.srto_max != 0)
2728 			asoc->rto_max = msecs_to_jiffies(rtoinfo.srto_max);
2729 		if (rtoinfo.srto_min != 0)
2730 			asoc->rto_min = msecs_to_jiffies(rtoinfo.srto_min);
2731 	} else {
2732 		/* If there is no association or the association-id = 0
2733 		 * set the values to the endpoint.
2734 		 */
2735 		struct sctp_sock *sp = sctp_sk(sk);
2736 
2737 		if (rtoinfo.srto_initial != 0)
2738 			sp->rtoinfo.srto_initial = rtoinfo.srto_initial;
2739 		if (rtoinfo.srto_max != 0)
2740 			sp->rtoinfo.srto_max = rtoinfo.srto_max;
2741 		if (rtoinfo.srto_min != 0)
2742 			sp->rtoinfo.srto_min = rtoinfo.srto_min;
2743 	}
2744 
2745 	return 0;
2746 }
2747 
2748 /*
2749  *
2750  * 7.1.2 SCTP_ASSOCINFO
2751  *
2752  * This option is used to tune the maximum retransmission attempts
2753  * of the association.
2754  * Returns an error if the new association retransmission value is
2755  * greater than the sum of the retransmission value  of the peer.
2756  * See [SCTP] for more information.
2757  *
2758  */
sctp_setsockopt_associnfo(struct sock * sk,char __user * optval,unsigned int optlen)2759 static int sctp_setsockopt_associnfo(struct sock *sk, char __user *optval, unsigned int optlen)
2760 {
2761 
2762 	struct sctp_assocparams assocparams;
2763 	struct sctp_association *asoc;
2764 
2765 	if (optlen != sizeof(struct sctp_assocparams))
2766 		return -EINVAL;
2767 	if (copy_from_user(&assocparams, optval, optlen))
2768 		return -EFAULT;
2769 
2770 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
2771 
2772 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
2773 		return -EINVAL;
2774 
2775 	/* Set the values to the specific association */
2776 	if (asoc) {
2777 		if (assocparams.sasoc_asocmaxrxt != 0) {
2778 			__u32 path_sum = 0;
2779 			int   paths = 0;
2780 			struct sctp_transport *peer_addr;
2781 
2782 			list_for_each_entry(peer_addr, &asoc->peer.transport_addr_list,
2783 					transports) {
2784 				path_sum += peer_addr->pathmaxrxt;
2785 				paths++;
2786 			}
2787 
2788 			/* Only validate asocmaxrxt if we have more than
2789 			 * one path/transport.  We do this because path
2790 			 * retransmissions are only counted when we have more
2791 			 * then one path.
2792 			 */
2793 			if (paths > 1 &&
2794 			    assocparams.sasoc_asocmaxrxt > path_sum)
2795 				return -EINVAL;
2796 
2797 			asoc->max_retrans = assocparams.sasoc_asocmaxrxt;
2798 		}
2799 
2800 		if (assocparams.sasoc_cookie_life != 0) {
2801 			asoc->cookie_life.tv_sec =
2802 					assocparams.sasoc_cookie_life / 1000;
2803 			asoc->cookie_life.tv_usec =
2804 					(assocparams.sasoc_cookie_life % 1000)
2805 					* 1000;
2806 		}
2807 	} else {
2808 		/* Set the values to the endpoint */
2809 		struct sctp_sock *sp = sctp_sk(sk);
2810 
2811 		if (assocparams.sasoc_asocmaxrxt != 0)
2812 			sp->assocparams.sasoc_asocmaxrxt =
2813 						assocparams.sasoc_asocmaxrxt;
2814 		if (assocparams.sasoc_cookie_life != 0)
2815 			sp->assocparams.sasoc_cookie_life =
2816 						assocparams.sasoc_cookie_life;
2817 	}
2818 	return 0;
2819 }
2820 
2821 /*
2822  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
2823  *
2824  * This socket option is a boolean flag which turns on or off mapped V4
2825  * addresses.  If this option is turned on and the socket is type
2826  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
2827  * If this option is turned off, then no mapping will be done of V4
2828  * addresses and a user will receive both PF_INET6 and PF_INET type
2829  * addresses on the socket.
2830  */
sctp_setsockopt_mappedv4(struct sock * sk,char __user * optval,unsigned int optlen)2831 static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsigned int optlen)
2832 {
2833 	int val;
2834 	struct sctp_sock *sp = sctp_sk(sk);
2835 
2836 	if (optlen < sizeof(int))
2837 		return -EINVAL;
2838 	if (get_user(val, (int __user *)optval))
2839 		return -EFAULT;
2840 	if (val)
2841 		sp->v4mapped = 1;
2842 	else
2843 		sp->v4mapped = 0;
2844 
2845 	return 0;
2846 }
2847 
2848 /*
2849  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
2850  * This option will get or set the maximum size to put in any outgoing
2851  * SCTP DATA chunk.  If a message is larger than this size it will be
2852  * fragmented by SCTP into the specified size.  Note that the underlying
2853  * SCTP implementation may fragment into smaller sized chunks when the
2854  * PMTU of the underlying association is smaller than the value set by
2855  * the user.  The default value for this option is '0' which indicates
2856  * the user is NOT limiting fragmentation and only the PMTU will effect
2857  * SCTP's choice of DATA chunk size.  Note also that values set larger
2858  * than the maximum size of an IP datagram will effectively let SCTP
2859  * control fragmentation (i.e. the same as setting this option to 0).
2860  *
2861  * The following structure is used to access and modify this parameter:
2862  *
2863  * struct sctp_assoc_value {
2864  *   sctp_assoc_t assoc_id;
2865  *   uint32_t assoc_value;
2866  * };
2867  *
2868  * assoc_id:  This parameter is ignored for one-to-one style sockets.
2869  *    For one-to-many style sockets this parameter indicates which
2870  *    association the user is performing an action upon.  Note that if
2871  *    this field's value is zero then the endpoints default value is
2872  *    changed (effecting future associations only).
2873  * assoc_value:  This parameter specifies the maximum size in bytes.
2874  */
sctp_setsockopt_maxseg(struct sock * sk,char __user * optval,unsigned int optlen)2875 static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
2876 {
2877 	struct sctp_assoc_value params;
2878 	struct sctp_association *asoc;
2879 	struct sctp_sock *sp = sctp_sk(sk);
2880 	int val;
2881 
2882 	if (optlen == sizeof(int)) {
2883 		pr_warn("Use of int in maxseg socket option deprecated\n");
2884 		pr_warn("Use struct sctp_assoc_value instead\n");
2885 		if (copy_from_user(&val, optval, optlen))
2886 			return -EFAULT;
2887 		params.assoc_id = 0;
2888 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
2889 		if (copy_from_user(&params, optval, optlen))
2890 			return -EFAULT;
2891 		val = params.assoc_value;
2892 	} else
2893 		return -EINVAL;
2894 
2895 	if ((val != 0) && ((val < 8) || (val > SCTP_MAX_CHUNK_LEN)))
2896 		return -EINVAL;
2897 
2898 	asoc = sctp_id2assoc(sk, params.assoc_id);
2899 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
2900 		return -EINVAL;
2901 
2902 	if (asoc) {
2903 		if (val == 0) {
2904 			val = asoc->pathmtu;
2905 			val -= sp->pf->af->net_header_len;
2906 			val -= sizeof(struct sctphdr) +
2907 					sizeof(struct sctp_data_chunk);
2908 		}
2909 		asoc->user_frag = val;
2910 		asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
2911 	} else {
2912 		sp->user_frag = val;
2913 	}
2914 
2915 	return 0;
2916 }
2917 
2918 
2919 /*
2920  *  7.1.9 Set Peer Primary Address (SCTP_SET_PEER_PRIMARY_ADDR)
2921  *
2922  *   Requests that the peer mark the enclosed address as the association
2923  *   primary. The enclosed address must be one of the association's
2924  *   locally bound addresses. The following structure is used to make a
2925  *   set primary request:
2926  */
sctp_setsockopt_peer_primary_addr(struct sock * sk,char __user * optval,unsigned int optlen)2927 static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optval,
2928 					     unsigned int optlen)
2929 {
2930 	struct sctp_sock	*sp;
2931 	struct sctp_association	*asoc = NULL;
2932 	struct sctp_setpeerprim	prim;
2933 	struct sctp_chunk	*chunk;
2934 	struct sctp_af		*af;
2935 	int 			err;
2936 
2937 	sp = sctp_sk(sk);
2938 
2939 	if (!sctp_addip_enable)
2940 		return -EPERM;
2941 
2942 	if (optlen != sizeof(struct sctp_setpeerprim))
2943 		return -EINVAL;
2944 
2945 	if (copy_from_user(&prim, optval, optlen))
2946 		return -EFAULT;
2947 
2948 	asoc = sctp_id2assoc(sk, prim.sspp_assoc_id);
2949 	if (!asoc)
2950 		return -EINVAL;
2951 
2952 	if (!asoc->peer.asconf_capable)
2953 		return -EPERM;
2954 
2955 	if (asoc->peer.addip_disabled_mask & SCTP_PARAM_SET_PRIMARY)
2956 		return -EPERM;
2957 
2958 	if (!sctp_state(asoc, ESTABLISHED))
2959 		return -ENOTCONN;
2960 
2961 	af = sctp_get_af_specific(prim.sspp_addr.ss_family);
2962 	if (!af)
2963 		return -EINVAL;
2964 
2965 	if (!af->addr_valid((union sctp_addr *)&prim.sspp_addr, sp, NULL))
2966 		return -EADDRNOTAVAIL;
2967 
2968 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
2969 		return -EADDRNOTAVAIL;
2970 
2971 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
2972 	chunk = sctp_make_asconf_set_prim(asoc,
2973 					  (union sctp_addr *)&prim.sspp_addr);
2974 	if (!chunk)
2975 		return -ENOMEM;
2976 
2977 	err = sctp_send_asconf(asoc, chunk);
2978 
2979 	SCTP_DEBUG_PRINTK("We set peer primary addr primitively.\n");
2980 
2981 	return err;
2982 }
2983 
sctp_setsockopt_adaptation_layer(struct sock * sk,char __user * optval,unsigned int optlen)2984 static int sctp_setsockopt_adaptation_layer(struct sock *sk, char __user *optval,
2985 					    unsigned int optlen)
2986 {
2987 	struct sctp_setadaptation adaptation;
2988 
2989 	if (optlen != sizeof(struct sctp_setadaptation))
2990 		return -EINVAL;
2991 	if (copy_from_user(&adaptation, optval, optlen))
2992 		return -EFAULT;
2993 
2994 	sctp_sk(sk)->adaptation_ind = adaptation.ssb_adaptation_ind;
2995 
2996 	return 0;
2997 }
2998 
2999 /*
3000  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
3001  *
3002  * The context field in the sctp_sndrcvinfo structure is normally only
3003  * used when a failed message is retrieved holding the value that was
3004  * sent down on the actual send call.  This option allows the setting of
3005  * a default context on an association basis that will be received on
3006  * reading messages from the peer.  This is especially helpful in the
3007  * one-2-many model for an application to keep some reference to an
3008  * internal state machine that is processing messages on the
3009  * association.  Note that the setting of this value only effects
3010  * received messages from the peer and does not effect the value that is
3011  * saved with outbound messages.
3012  */
sctp_setsockopt_context(struct sock * sk,char __user * optval,unsigned int optlen)3013 static int sctp_setsockopt_context(struct sock *sk, char __user *optval,
3014 				   unsigned int optlen)
3015 {
3016 	struct sctp_assoc_value params;
3017 	struct sctp_sock *sp;
3018 	struct sctp_association *asoc;
3019 
3020 	if (optlen != sizeof(struct sctp_assoc_value))
3021 		return -EINVAL;
3022 	if (copy_from_user(&params, optval, optlen))
3023 		return -EFAULT;
3024 
3025 	sp = sctp_sk(sk);
3026 
3027 	if (params.assoc_id != 0) {
3028 		asoc = sctp_id2assoc(sk, params.assoc_id);
3029 		if (!asoc)
3030 			return -EINVAL;
3031 		asoc->default_rcv_context = params.assoc_value;
3032 	} else {
3033 		sp->default_rcv_context = params.assoc_value;
3034 	}
3035 
3036 	return 0;
3037 }
3038 
3039 /*
3040  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
3041  *
3042  * This options will at a minimum specify if the implementation is doing
3043  * fragmented interleave.  Fragmented interleave, for a one to many
3044  * socket, is when subsequent calls to receive a message may return
3045  * parts of messages from different associations.  Some implementations
3046  * may allow you to turn this value on or off.  If so, when turned off,
3047  * no fragment interleave will occur (which will cause a head of line
3048  * blocking amongst multiple associations sharing the same one to many
3049  * socket).  When this option is turned on, then each receive call may
3050  * come from a different association (thus the user must receive data
3051  * with the extended calls (e.g. sctp_recvmsg) to keep track of which
3052  * association each receive belongs to.
3053  *
3054  * This option takes a boolean value.  A non-zero value indicates that
3055  * fragmented interleave is on.  A value of zero indicates that
3056  * fragmented interleave is off.
3057  *
3058  * Note that it is important that an implementation that allows this
3059  * option to be turned on, have it off by default.  Otherwise an unaware
3060  * application using the one to many model may become confused and act
3061  * incorrectly.
3062  */
sctp_setsockopt_fragment_interleave(struct sock * sk,char __user * optval,unsigned int optlen)3063 static int sctp_setsockopt_fragment_interleave(struct sock *sk,
3064 					       char __user *optval,
3065 					       unsigned int optlen)
3066 {
3067 	int val;
3068 
3069 	if (optlen != sizeof(int))
3070 		return -EINVAL;
3071 	if (get_user(val, (int __user *)optval))
3072 		return -EFAULT;
3073 
3074 	sctp_sk(sk)->frag_interleave = (val == 0) ? 0 : 1;
3075 
3076 	return 0;
3077 }
3078 
3079 /*
3080  * 8.1.21.  Set or Get the SCTP Partial Delivery Point
3081  *       (SCTP_PARTIAL_DELIVERY_POINT)
3082  *
3083  * This option will set or get the SCTP partial delivery point.  This
3084  * point is the size of a message where the partial delivery API will be
3085  * invoked to help free up rwnd space for the peer.  Setting this to a
3086  * lower value will cause partial deliveries to happen more often.  The
3087  * calls argument is an integer that sets or gets the partial delivery
3088  * point.  Note also that the call will fail if the user attempts to set
3089  * this value larger than the socket receive buffer size.
3090  *
3091  * Note that any single message having a length smaller than or equal to
3092  * the SCTP partial delivery point will be delivered in one single read
3093  * call as long as the user provided buffer is large enough to hold the
3094  * message.
3095  */
sctp_setsockopt_partial_delivery_point(struct sock * sk,char __user * optval,unsigned int optlen)3096 static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
3097 						  char __user *optval,
3098 						  unsigned int optlen)
3099 {
3100 	u32 val;
3101 
3102 	if (optlen != sizeof(u32))
3103 		return -EINVAL;
3104 	if (get_user(val, (int __user *)optval))
3105 		return -EFAULT;
3106 
3107 	/* Note: We double the receive buffer from what the user sets
3108 	 * it to be, also initial rwnd is based on rcvbuf/2.
3109 	 */
3110 	if (val > (sk->sk_rcvbuf >> 1))
3111 		return -EINVAL;
3112 
3113 	sctp_sk(sk)->pd_point = val;
3114 
3115 	return 0; /* is this the right error code? */
3116 }
3117 
3118 /*
3119  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
3120  *
3121  * This option will allow a user to change the maximum burst of packets
3122  * that can be emitted by this association.  Note that the default value
3123  * is 4, and some implementations may restrict this setting so that it
3124  * can only be lowered.
3125  *
3126  * NOTE: This text doesn't seem right.  Do this on a socket basis with
3127  * future associations inheriting the socket value.
3128  */
sctp_setsockopt_maxburst(struct sock * sk,char __user * optval,unsigned int optlen)3129 static int sctp_setsockopt_maxburst(struct sock *sk,
3130 				    char __user *optval,
3131 				    unsigned int optlen)
3132 {
3133 	struct sctp_assoc_value params;
3134 	struct sctp_sock *sp;
3135 	struct sctp_association *asoc;
3136 	int val;
3137 	int assoc_id = 0;
3138 
3139 	if (optlen == sizeof(int)) {
3140 		pr_warn("Use of int in max_burst socket option deprecated\n");
3141 		pr_warn("Use struct sctp_assoc_value instead\n");
3142 		if (copy_from_user(&val, optval, optlen))
3143 			return -EFAULT;
3144 	} else if (optlen == sizeof(struct sctp_assoc_value)) {
3145 		if (copy_from_user(&params, optval, optlen))
3146 			return -EFAULT;
3147 		val = params.assoc_value;
3148 		assoc_id = params.assoc_id;
3149 	} else
3150 		return -EINVAL;
3151 
3152 	sp = sctp_sk(sk);
3153 
3154 	if (assoc_id != 0) {
3155 		asoc = sctp_id2assoc(sk, assoc_id);
3156 		if (!asoc)
3157 			return -EINVAL;
3158 		asoc->max_burst = val;
3159 	} else
3160 		sp->max_burst = val;
3161 
3162 	return 0;
3163 }
3164 
3165 /*
3166  * 7.1.18.  Add a chunk that must be authenticated (SCTP_AUTH_CHUNK)
3167  *
3168  * This set option adds a chunk type that the user is requesting to be
3169  * received only in an authenticated way.  Changes to the list of chunks
3170  * will only effect future associations on the socket.
3171  */
sctp_setsockopt_auth_chunk(struct sock * sk,char __user * optval,unsigned int optlen)3172 static int sctp_setsockopt_auth_chunk(struct sock *sk,
3173 				      char __user *optval,
3174 				      unsigned int optlen)
3175 {
3176 	struct sctp_authchunk val;
3177 
3178 	if (!sctp_auth_enable)
3179 		return -EACCES;
3180 
3181 	if (optlen != sizeof(struct sctp_authchunk))
3182 		return -EINVAL;
3183 	if (copy_from_user(&val, optval, optlen))
3184 		return -EFAULT;
3185 
3186 	switch (val.sauth_chunk) {
3187 		case SCTP_CID_INIT:
3188 		case SCTP_CID_INIT_ACK:
3189 		case SCTP_CID_SHUTDOWN_COMPLETE:
3190 		case SCTP_CID_AUTH:
3191 			return -EINVAL;
3192 	}
3193 
3194 	/* add this chunk id to the endpoint */
3195 	return sctp_auth_ep_add_chunkid(sctp_sk(sk)->ep, val.sauth_chunk);
3196 }
3197 
3198 /*
3199  * 7.1.19.  Get or set the list of supported HMAC Identifiers (SCTP_HMAC_IDENT)
3200  *
3201  * This option gets or sets the list of HMAC algorithms that the local
3202  * endpoint requires the peer to use.
3203  */
sctp_setsockopt_hmac_ident(struct sock * sk,char __user * optval,unsigned int optlen)3204 static int sctp_setsockopt_hmac_ident(struct sock *sk,
3205 				      char __user *optval,
3206 				      unsigned int optlen)
3207 {
3208 	struct sctp_hmacalgo *hmacs;
3209 	u32 idents;
3210 	int err;
3211 
3212 	if (!sctp_auth_enable)
3213 		return -EACCES;
3214 
3215 	if (optlen < sizeof(struct sctp_hmacalgo))
3216 		return -EINVAL;
3217 
3218 	hmacs = kmalloc(optlen, GFP_KERNEL);
3219 	if (!hmacs)
3220 		return -ENOMEM;
3221 
3222 	if (copy_from_user(hmacs, optval, optlen)) {
3223 		err = -EFAULT;
3224 		goto out;
3225 	}
3226 
3227 	idents = hmacs->shmac_num_idents;
3228 	if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS ||
3229 	    (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo))) {
3230 		err = -EINVAL;
3231 		goto out;
3232 	}
3233 
3234 	err = sctp_auth_ep_set_hmacs(sctp_sk(sk)->ep, hmacs);
3235 out:
3236 	kfree(hmacs);
3237 	return err;
3238 }
3239 
3240 /*
3241  * 7.1.20.  Set a shared key (SCTP_AUTH_KEY)
3242  *
3243  * This option will set a shared secret key which is used to build an
3244  * association shared key.
3245  */
sctp_setsockopt_auth_key(struct sock * sk,char __user * optval,unsigned int optlen)3246 static int sctp_setsockopt_auth_key(struct sock *sk,
3247 				    char __user *optval,
3248 				    unsigned int optlen)
3249 {
3250 	struct sctp_authkey *authkey;
3251 	struct sctp_association *asoc;
3252 	int ret;
3253 
3254 	if (!sctp_auth_enable)
3255 		return -EACCES;
3256 
3257 	if (optlen <= sizeof(struct sctp_authkey))
3258 		return -EINVAL;
3259 
3260 	authkey = kmalloc(optlen, GFP_KERNEL);
3261 	if (!authkey)
3262 		return -ENOMEM;
3263 
3264 	if (copy_from_user(authkey, optval, optlen)) {
3265 		ret = -EFAULT;
3266 		goto out;
3267 	}
3268 
3269 	if (authkey->sca_keylength > optlen - sizeof(struct sctp_authkey)) {
3270 		ret = -EINVAL;
3271 		goto out;
3272 	}
3273 
3274 	asoc = sctp_id2assoc(sk, authkey->sca_assoc_id);
3275 	if (!asoc && authkey->sca_assoc_id && sctp_style(sk, UDP)) {
3276 		ret = -EINVAL;
3277 		goto out;
3278 	}
3279 
3280 	ret = sctp_auth_set_key(sctp_sk(sk)->ep, asoc, authkey);
3281 out:
3282 	kfree(authkey);
3283 	return ret;
3284 }
3285 
3286 /*
3287  * 7.1.21.  Get or set the active shared key (SCTP_AUTH_ACTIVE_KEY)
3288  *
3289  * This option will get or set the active shared key to be used to build
3290  * the association shared key.
3291  */
sctp_setsockopt_active_key(struct sock * sk,char __user * optval,unsigned int optlen)3292 static int sctp_setsockopt_active_key(struct sock *sk,
3293 				      char __user *optval,
3294 				      unsigned int optlen)
3295 {
3296 	struct sctp_authkeyid val;
3297 	struct sctp_association *asoc;
3298 
3299 	if (!sctp_auth_enable)
3300 		return -EACCES;
3301 
3302 	if (optlen != sizeof(struct sctp_authkeyid))
3303 		return -EINVAL;
3304 	if (copy_from_user(&val, optval, optlen))
3305 		return -EFAULT;
3306 
3307 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3308 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3309 		return -EINVAL;
3310 
3311 	return sctp_auth_set_active_key(sctp_sk(sk)->ep, asoc,
3312 					val.scact_keynumber);
3313 }
3314 
3315 /*
3316  * 7.1.22.  Delete a shared key (SCTP_AUTH_DELETE_KEY)
3317  *
3318  * This set option will delete a shared secret key from use.
3319  */
sctp_setsockopt_del_key(struct sock * sk,char __user * optval,unsigned int optlen)3320 static int sctp_setsockopt_del_key(struct sock *sk,
3321 				   char __user *optval,
3322 				   unsigned int optlen)
3323 {
3324 	struct sctp_authkeyid val;
3325 	struct sctp_association *asoc;
3326 
3327 	if (!sctp_auth_enable)
3328 		return -EACCES;
3329 
3330 	if (optlen != sizeof(struct sctp_authkeyid))
3331 		return -EINVAL;
3332 	if (copy_from_user(&val, optval, optlen))
3333 		return -EFAULT;
3334 
3335 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
3336 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
3337 		return -EINVAL;
3338 
3339 	return sctp_auth_del_key_id(sctp_sk(sk)->ep, asoc,
3340 				    val.scact_keynumber);
3341 
3342 }
3343 
3344 
3345 /* API 6.2 setsockopt(), getsockopt()
3346  *
3347  * Applications use setsockopt() and getsockopt() to set or retrieve
3348  * socket options.  Socket options are used to change the default
3349  * behavior of sockets calls.  They are described in Section 7.
3350  *
3351  * The syntax is:
3352  *
3353  *   ret = getsockopt(int sd, int level, int optname, void __user *optval,
3354  *                    int __user *optlen);
3355  *   ret = setsockopt(int sd, int level, int optname, const void __user *optval,
3356  *                    int optlen);
3357  *
3358  *   sd      - the socket descript.
3359  *   level   - set to IPPROTO_SCTP for all SCTP options.
3360  *   optname - the option name.
3361  *   optval  - the buffer to store the value of the option.
3362  *   optlen  - the size of the buffer.
3363  */
sctp_setsockopt(struct sock * sk,int level,int optname,char __user * optval,unsigned int optlen)3364 SCTP_STATIC int sctp_setsockopt(struct sock *sk, int level, int optname,
3365 				char __user *optval, unsigned int optlen)
3366 {
3367 	int retval = 0;
3368 
3369 	SCTP_DEBUG_PRINTK("sctp_setsockopt(sk: %p... optname: %d)\n",
3370 			  sk, optname);
3371 
3372 	/* I can hardly begin to describe how wrong this is.  This is
3373 	 * so broken as to be worse than useless.  The API draft
3374 	 * REALLY is NOT helpful here...  I am not convinced that the
3375 	 * semantics of setsockopt() with a level OTHER THAN SOL_SCTP
3376 	 * are at all well-founded.
3377 	 */
3378 	if (level != SOL_SCTP) {
3379 		struct sctp_af *af = sctp_sk(sk)->pf->af;
3380 		retval = af->setsockopt(sk, level, optname, optval, optlen);
3381 		goto out_nounlock;
3382 	}
3383 
3384 	sctp_lock_sock(sk);
3385 
3386 	switch (optname) {
3387 	case SCTP_SOCKOPT_BINDX_ADD:
3388 		/* 'optlen' is the size of the addresses buffer. */
3389 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3390 					       optlen, SCTP_BINDX_ADD_ADDR);
3391 		break;
3392 
3393 	case SCTP_SOCKOPT_BINDX_REM:
3394 		/* 'optlen' is the size of the addresses buffer. */
3395 		retval = sctp_setsockopt_bindx(sk, (struct sockaddr __user *)optval,
3396 					       optlen, SCTP_BINDX_REM_ADDR);
3397 		break;
3398 
3399 	case SCTP_SOCKOPT_CONNECTX_OLD:
3400 		/* 'optlen' is the size of the addresses buffer. */
3401 		retval = sctp_setsockopt_connectx_old(sk,
3402 					    (struct sockaddr __user *)optval,
3403 					    optlen);
3404 		break;
3405 
3406 	case SCTP_SOCKOPT_CONNECTX:
3407 		/* 'optlen' is the size of the addresses buffer. */
3408 		retval = sctp_setsockopt_connectx(sk,
3409 					    (struct sockaddr __user *)optval,
3410 					    optlen);
3411 		break;
3412 
3413 	case SCTP_DISABLE_FRAGMENTS:
3414 		retval = sctp_setsockopt_disable_fragments(sk, optval, optlen);
3415 		break;
3416 
3417 	case SCTP_EVENTS:
3418 		retval = sctp_setsockopt_events(sk, optval, optlen);
3419 		break;
3420 
3421 	case SCTP_AUTOCLOSE:
3422 		retval = sctp_setsockopt_autoclose(sk, optval, optlen);
3423 		break;
3424 
3425 	case SCTP_PEER_ADDR_PARAMS:
3426 		retval = sctp_setsockopt_peer_addr_params(sk, optval, optlen);
3427 		break;
3428 
3429 	case SCTP_DELAYED_SACK:
3430 		retval = sctp_setsockopt_delayed_ack(sk, optval, optlen);
3431 		break;
3432 	case SCTP_PARTIAL_DELIVERY_POINT:
3433 		retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
3434 		break;
3435 
3436 	case SCTP_INITMSG:
3437 		retval = sctp_setsockopt_initmsg(sk, optval, optlen);
3438 		break;
3439 	case SCTP_DEFAULT_SEND_PARAM:
3440 		retval = sctp_setsockopt_default_send_param(sk, optval,
3441 							    optlen);
3442 		break;
3443 	case SCTP_PRIMARY_ADDR:
3444 		retval = sctp_setsockopt_primary_addr(sk, optval, optlen);
3445 		break;
3446 	case SCTP_SET_PEER_PRIMARY_ADDR:
3447 		retval = sctp_setsockopt_peer_primary_addr(sk, optval, optlen);
3448 		break;
3449 	case SCTP_NODELAY:
3450 		retval = sctp_setsockopt_nodelay(sk, optval, optlen);
3451 		break;
3452 	case SCTP_RTOINFO:
3453 		retval = sctp_setsockopt_rtoinfo(sk, optval, optlen);
3454 		break;
3455 	case SCTP_ASSOCINFO:
3456 		retval = sctp_setsockopt_associnfo(sk, optval, optlen);
3457 		break;
3458 	case SCTP_I_WANT_MAPPED_V4_ADDR:
3459 		retval = sctp_setsockopt_mappedv4(sk, optval, optlen);
3460 		break;
3461 	case SCTP_MAXSEG:
3462 		retval = sctp_setsockopt_maxseg(sk, optval, optlen);
3463 		break;
3464 	case SCTP_ADAPTATION_LAYER:
3465 		retval = sctp_setsockopt_adaptation_layer(sk, optval, optlen);
3466 		break;
3467 	case SCTP_CONTEXT:
3468 		retval = sctp_setsockopt_context(sk, optval, optlen);
3469 		break;
3470 	case SCTP_FRAGMENT_INTERLEAVE:
3471 		retval = sctp_setsockopt_fragment_interleave(sk, optval, optlen);
3472 		break;
3473 	case SCTP_MAX_BURST:
3474 		retval = sctp_setsockopt_maxburst(sk, optval, optlen);
3475 		break;
3476 	case SCTP_AUTH_CHUNK:
3477 		retval = sctp_setsockopt_auth_chunk(sk, optval, optlen);
3478 		break;
3479 	case SCTP_HMAC_IDENT:
3480 		retval = sctp_setsockopt_hmac_ident(sk, optval, optlen);
3481 		break;
3482 	case SCTP_AUTH_KEY:
3483 		retval = sctp_setsockopt_auth_key(sk, optval, optlen);
3484 		break;
3485 	case SCTP_AUTH_ACTIVE_KEY:
3486 		retval = sctp_setsockopt_active_key(sk, optval, optlen);
3487 		break;
3488 	case SCTP_AUTH_DELETE_KEY:
3489 		retval = sctp_setsockopt_del_key(sk, optval, optlen);
3490 		break;
3491 	default:
3492 		retval = -ENOPROTOOPT;
3493 		break;
3494 	}
3495 
3496 	sctp_release_sock(sk);
3497 
3498 out_nounlock:
3499 	return retval;
3500 }
3501 
3502 /* API 3.1.6 connect() - UDP Style Syntax
3503  *
3504  * An application may use the connect() call in the UDP model to initiate an
3505  * association without sending data.
3506  *
3507  * The syntax is:
3508  *
3509  * ret = connect(int sd, const struct sockaddr *nam, socklen_t len);
3510  *
3511  * sd: the socket descriptor to have a new association added to.
3512  *
3513  * nam: the address structure (either struct sockaddr_in or struct
3514  *    sockaddr_in6 defined in RFC2553 [7]).
3515  *
3516  * len: the size of the address.
3517  */
sctp_connect(struct sock * sk,struct sockaddr * addr,int addr_len)3518 SCTP_STATIC int sctp_connect(struct sock *sk, struct sockaddr *addr,
3519 			     int addr_len)
3520 {
3521 	int err = 0;
3522 	struct sctp_af *af;
3523 
3524 	sctp_lock_sock(sk);
3525 
3526 	SCTP_DEBUG_PRINTK("%s - sk: %p, sockaddr: %p, addr_len: %d\n",
3527 			  __func__, sk, addr, addr_len);
3528 
3529 	/* Validate addr_len before calling common connect/connectx routine. */
3530 	af = sctp_get_af_specific(addr->sa_family);
3531 	if (!af || addr_len < af->sockaddr_len) {
3532 		err = -EINVAL;
3533 	} else {
3534 		/* Pass correct addr len to common routine (so it knows there
3535 		 * is only one address being passed.
3536 		 */
3537 		err = __sctp_connect(sk, addr, af->sockaddr_len, NULL);
3538 	}
3539 
3540 	sctp_release_sock(sk);
3541 	return err;
3542 }
3543 
3544 /* FIXME: Write comments. */
sctp_disconnect(struct sock * sk,int flags)3545 SCTP_STATIC int sctp_disconnect(struct sock *sk, int flags)
3546 {
3547 	return -EOPNOTSUPP; /* STUB */
3548 }
3549 
3550 /* 4.1.4 accept() - TCP Style Syntax
3551  *
3552  * Applications use accept() call to remove an established SCTP
3553  * association from the accept queue of the endpoint.  A new socket
3554  * descriptor will be returned from accept() to represent the newly
3555  * formed association.
3556  */
sctp_accept(struct sock * sk,int flags,int * err)3557 SCTP_STATIC struct sock *sctp_accept(struct sock *sk, int flags, int *err)
3558 {
3559 	struct sctp_sock *sp;
3560 	struct sctp_endpoint *ep;
3561 	struct sock *newsk = NULL;
3562 	struct sctp_association *asoc;
3563 	long timeo;
3564 	int error = 0;
3565 
3566 	sctp_lock_sock(sk);
3567 
3568 	sp = sctp_sk(sk);
3569 	ep = sp->ep;
3570 
3571 	if (!sctp_style(sk, TCP)) {
3572 		error = -EOPNOTSUPP;
3573 		goto out;
3574 	}
3575 
3576 	if (!sctp_sstate(sk, LISTENING)) {
3577 		error = -EINVAL;
3578 		goto out;
3579 	}
3580 
3581 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
3582 
3583 	error = sctp_wait_for_accept(sk, timeo);
3584 	if (error)
3585 		goto out;
3586 
3587 	/* We treat the list of associations on the endpoint as the accept
3588 	 * queue and pick the first association on the list.
3589 	 */
3590 	asoc = list_entry(ep->asocs.next, struct sctp_association, asocs);
3591 
3592 	newsk = sp->pf->create_accept_sk(sk, asoc);
3593 	if (!newsk) {
3594 		error = -ENOMEM;
3595 		goto out;
3596 	}
3597 
3598 	/* Populate the fields of the newsk from the oldsk and migrate the
3599 	 * asoc to the newsk.
3600 	 */
3601 	sctp_sock_migrate(sk, newsk, asoc, SCTP_SOCKET_TCP);
3602 
3603 out:
3604 	sctp_release_sock(sk);
3605 	*err = error;
3606 	return newsk;
3607 }
3608 
3609 /* The SCTP ioctl handler. */
sctp_ioctl(struct sock * sk,int cmd,unsigned long arg)3610 SCTP_STATIC int sctp_ioctl(struct sock *sk, int cmd, unsigned long arg)
3611 {
3612 	int rc = -ENOTCONN;
3613 
3614 	sctp_lock_sock(sk);
3615 
3616 	/*
3617 	 * SEQPACKET-style sockets in LISTENING state are valid, for
3618 	 * SCTP, so only discard TCP-style sockets in LISTENING state.
3619 	 */
3620 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
3621 		goto out;
3622 
3623 	switch (cmd) {
3624 	case SIOCINQ: {
3625 		struct sk_buff *skb;
3626 		unsigned int amount = 0;
3627 
3628 		skb = skb_peek(&sk->sk_receive_queue);
3629 		if (skb != NULL) {
3630 			/*
3631 			 * We will only return the amount of this packet since
3632 			 * that is all that will be read.
3633 			 */
3634 			amount = skb->len;
3635 		}
3636 		rc = put_user(amount, (int __user *)arg);
3637 		break;
3638 	}
3639 	default:
3640 		rc = -ENOIOCTLCMD;
3641 		break;
3642 	}
3643 out:
3644 	sctp_release_sock(sk);
3645 	return rc;
3646 }
3647 
3648 /* This is the function which gets called during socket creation to
3649  * initialized the SCTP-specific portion of the sock.
3650  * The sock structure should already be zero-filled memory.
3651  */
sctp_init_sock(struct sock * sk)3652 SCTP_STATIC int sctp_init_sock(struct sock *sk)
3653 {
3654 	struct sctp_endpoint *ep;
3655 	struct sctp_sock *sp;
3656 
3657 	SCTP_DEBUG_PRINTK("sctp_init_sock(sk: %p)\n", sk);
3658 
3659 	sp = sctp_sk(sk);
3660 
3661 	/* Initialize the SCTP per socket area.  */
3662 	switch (sk->sk_type) {
3663 	case SOCK_SEQPACKET:
3664 		sp->type = SCTP_SOCKET_UDP;
3665 		break;
3666 	case SOCK_STREAM:
3667 		sp->type = SCTP_SOCKET_TCP;
3668 		break;
3669 	default:
3670 		return -ESOCKTNOSUPPORT;
3671 	}
3672 
3673 	/* Initialize default send parameters. These parameters can be
3674 	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
3675 	 */
3676 	sp->default_stream = 0;
3677 	sp->default_ppid = 0;
3678 	sp->default_flags = 0;
3679 	sp->default_context = 0;
3680 	sp->default_timetolive = 0;
3681 
3682 	sp->default_rcv_context = 0;
3683 	sp->max_burst = sctp_max_burst;
3684 
3685 	/* Initialize default setup parameters. These parameters
3686 	 * can be modified with the SCTP_INITMSG socket option or
3687 	 * overridden by the SCTP_INIT CMSG.
3688 	 */
3689 	sp->initmsg.sinit_num_ostreams   = sctp_max_outstreams;
3690 	sp->initmsg.sinit_max_instreams  = sctp_max_instreams;
3691 	sp->initmsg.sinit_max_attempts   = sctp_max_retrans_init;
3692 	sp->initmsg.sinit_max_init_timeo = sctp_rto_max;
3693 
3694 	/* Initialize default RTO related parameters.  These parameters can
3695 	 * be modified for with the SCTP_RTOINFO socket option.
3696 	 */
3697 	sp->rtoinfo.srto_initial = sctp_rto_initial;
3698 	sp->rtoinfo.srto_max     = sctp_rto_max;
3699 	sp->rtoinfo.srto_min     = sctp_rto_min;
3700 
3701 	/* Initialize default association related parameters. These parameters
3702 	 * can be modified with the SCTP_ASSOCINFO socket option.
3703 	 */
3704 	sp->assocparams.sasoc_asocmaxrxt = sctp_max_retrans_association;
3705 	sp->assocparams.sasoc_number_peer_destinations = 0;
3706 	sp->assocparams.sasoc_peer_rwnd = 0;
3707 	sp->assocparams.sasoc_local_rwnd = 0;
3708 	sp->assocparams.sasoc_cookie_life = sctp_valid_cookie_life;
3709 
3710 	/* Initialize default event subscriptions. By default, all the
3711 	 * options are off.
3712 	 */
3713 	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
3714 
3715 	/* Default Peer Address Parameters.  These defaults can
3716 	 * be modified via SCTP_PEER_ADDR_PARAMS
3717 	 */
3718 	sp->hbinterval  = sctp_hb_interval;
3719 	sp->pathmaxrxt  = sctp_max_retrans_path;
3720 	sp->pathmtu     = 0; // allow default discovery
3721 	sp->sackdelay   = sctp_sack_timeout;
3722 	sp->sackfreq	= 2;
3723 	sp->param_flags = SPP_HB_ENABLE |
3724 			  SPP_PMTUD_ENABLE |
3725 			  SPP_SACKDELAY_ENABLE;
3726 
3727 	/* If enabled no SCTP message fragmentation will be performed.
3728 	 * Configure through SCTP_DISABLE_FRAGMENTS socket option.
3729 	 */
3730 	sp->disable_fragments = 0;
3731 
3732 	/* Enable Nagle algorithm by default.  */
3733 	sp->nodelay           = 0;
3734 
3735 	/* Enable by default. */
3736 	sp->v4mapped          = 1;
3737 
3738 	/* Auto-close idle associations after the configured
3739 	 * number of seconds.  A value of 0 disables this
3740 	 * feature.  Configure through the SCTP_AUTOCLOSE socket option,
3741 	 * for UDP-style sockets only.
3742 	 */
3743 	sp->autoclose         = 0;
3744 
3745 	/* User specified fragmentation limit. */
3746 	sp->user_frag         = 0;
3747 
3748 	sp->adaptation_ind = 0;
3749 
3750 	sp->pf = sctp_get_pf_specific(sk->sk_family);
3751 
3752 	/* Control variables for partial data delivery. */
3753 	atomic_set(&sp->pd_mode, 0);
3754 	skb_queue_head_init(&sp->pd_lobby);
3755 	sp->frag_interleave = 0;
3756 
3757 	/* Create a per socket endpoint structure.  Even if we
3758 	 * change the data structure relationships, this may still
3759 	 * be useful for storing pre-connect address information.
3760 	 */
3761 	ep = sctp_endpoint_new(sk, GFP_KERNEL);
3762 	if (!ep)
3763 		return -ENOMEM;
3764 
3765 	sp->ep = ep;
3766 	sp->hmac = NULL;
3767 
3768 	SCTP_DBG_OBJCNT_INC(sock);
3769 
3770 	local_bh_disable();
3771 	percpu_counter_inc(&sctp_sockets_allocated);
3772 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
3773 	local_bh_enable();
3774 
3775 	return 0;
3776 }
3777 
3778 /* Cleanup any SCTP per socket resources.  */
sctp_destroy_sock(struct sock * sk)3779 SCTP_STATIC void sctp_destroy_sock(struct sock *sk)
3780 {
3781 	struct sctp_endpoint *ep;
3782 
3783 	SCTP_DEBUG_PRINTK("sctp_destroy_sock(sk: %p)\n", sk);
3784 
3785 	/* Release our hold on the endpoint. */
3786 	ep = sctp_sk(sk)->ep;
3787 	sctp_endpoint_free(ep);
3788 	local_bh_disable();
3789 	percpu_counter_dec(&sctp_sockets_allocated);
3790 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
3791 	local_bh_enable();
3792 }
3793 
3794 /* API 4.1.7 shutdown() - TCP Style Syntax
3795  *     int shutdown(int socket, int how);
3796  *
3797  *     sd      - the socket descriptor of the association to be closed.
3798  *     how     - Specifies the type of shutdown.  The  values  are
3799  *               as follows:
3800  *               SHUT_RD
3801  *                     Disables further receive operations. No SCTP
3802  *                     protocol action is taken.
3803  *               SHUT_WR
3804  *                     Disables further send operations, and initiates
3805  *                     the SCTP shutdown sequence.
3806  *               SHUT_RDWR
3807  *                     Disables further send  and  receive  operations
3808  *                     and initiates the SCTP shutdown sequence.
3809  */
sctp_shutdown(struct sock * sk,int how)3810 SCTP_STATIC void sctp_shutdown(struct sock *sk, int how)
3811 {
3812 	struct sctp_endpoint *ep;
3813 	struct sctp_association *asoc;
3814 
3815 	if (!sctp_style(sk, TCP))
3816 		return;
3817 
3818 	if (how & SEND_SHUTDOWN) {
3819 		ep = sctp_sk(sk)->ep;
3820 		if (!list_empty(&ep->asocs)) {
3821 			asoc = list_entry(ep->asocs.next,
3822 					  struct sctp_association, asocs);
3823 			sctp_primitive_SHUTDOWN(asoc, NULL);
3824 		}
3825 	}
3826 }
3827 
3828 /* 7.2.1 Association Status (SCTP_STATUS)
3829 
3830  * Applications can retrieve current status information about an
3831  * association, including association state, peer receiver window size,
3832  * number of unacked data chunks, and number of data chunks pending
3833  * receipt.  This information is read-only.
3834  */
sctp_getsockopt_sctp_status(struct sock * sk,int len,char __user * optval,int __user * optlen)3835 static int sctp_getsockopt_sctp_status(struct sock *sk, int len,
3836 				       char __user *optval,
3837 				       int __user *optlen)
3838 {
3839 	struct sctp_status status;
3840 	struct sctp_association *asoc = NULL;
3841 	struct sctp_transport *transport;
3842 	sctp_assoc_t associd;
3843 	int retval = 0;
3844 
3845 	if (len < sizeof(status)) {
3846 		retval = -EINVAL;
3847 		goto out;
3848 	}
3849 
3850 	len = sizeof(status);
3851 	if (copy_from_user(&status, optval, len)) {
3852 		retval = -EFAULT;
3853 		goto out;
3854 	}
3855 
3856 	associd = status.sstat_assoc_id;
3857 	asoc = sctp_id2assoc(sk, associd);
3858 	if (!asoc) {
3859 		retval = -EINVAL;
3860 		goto out;
3861 	}
3862 
3863 	transport = asoc->peer.primary_path;
3864 
3865 	status.sstat_assoc_id = sctp_assoc2id(asoc);
3866 	status.sstat_state = asoc->state;
3867 	status.sstat_rwnd =  asoc->peer.rwnd;
3868 	status.sstat_unackdata = asoc->unack_data;
3869 
3870 	status.sstat_penddata = sctp_tsnmap_pending(&asoc->peer.tsn_map);
3871 	status.sstat_instrms = asoc->c.sinit_max_instreams;
3872 	status.sstat_outstrms = asoc->c.sinit_num_ostreams;
3873 	status.sstat_fragmentation_point = asoc->frag_point;
3874 	status.sstat_primary.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3875 	memcpy(&status.sstat_primary.spinfo_address, &transport->ipaddr,
3876 			transport->af_specific->sockaddr_len);
3877 	/* Map ipv4 address into v4-mapped-on-v6 address.  */
3878 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
3879 		(union sctp_addr *)&status.sstat_primary.spinfo_address);
3880 	status.sstat_primary.spinfo_state = transport->state;
3881 	status.sstat_primary.spinfo_cwnd = transport->cwnd;
3882 	status.sstat_primary.spinfo_srtt = transport->srtt;
3883 	status.sstat_primary.spinfo_rto = jiffies_to_msecs(transport->rto);
3884 	status.sstat_primary.spinfo_mtu = transport->pathmtu;
3885 
3886 	if (status.sstat_primary.spinfo_state == SCTP_UNKNOWN)
3887 		status.sstat_primary.spinfo_state = SCTP_ACTIVE;
3888 
3889 	if (put_user(len, optlen)) {
3890 		retval = -EFAULT;
3891 		goto out;
3892 	}
3893 
3894 	SCTP_DEBUG_PRINTK("sctp_getsockopt_sctp_status(%d): %d %d %d\n",
3895 			  len, status.sstat_state, status.sstat_rwnd,
3896 			  status.sstat_assoc_id);
3897 
3898 	if (copy_to_user(optval, &status, len)) {
3899 		retval = -EFAULT;
3900 		goto out;
3901 	}
3902 
3903 out:
3904 	return retval;
3905 }
3906 
3907 
3908 /* 7.2.2 Peer Address Information (SCTP_GET_PEER_ADDR_INFO)
3909  *
3910  * Applications can retrieve information about a specific peer address
3911  * of an association, including its reachability state, congestion
3912  * window, and retransmission timer values.  This information is
3913  * read-only.
3914  */
sctp_getsockopt_peer_addr_info(struct sock * sk,int len,char __user * optval,int __user * optlen)3915 static int sctp_getsockopt_peer_addr_info(struct sock *sk, int len,
3916 					  char __user *optval,
3917 					  int __user *optlen)
3918 {
3919 	struct sctp_paddrinfo pinfo;
3920 	struct sctp_transport *transport;
3921 	int retval = 0;
3922 
3923 	if (len < sizeof(pinfo)) {
3924 		retval = -EINVAL;
3925 		goto out;
3926 	}
3927 
3928 	len = sizeof(pinfo);
3929 	if (copy_from_user(&pinfo, optval, len)) {
3930 		retval = -EFAULT;
3931 		goto out;
3932 	}
3933 
3934 	transport = sctp_addr_id2transport(sk, &pinfo.spinfo_address,
3935 					   pinfo.spinfo_assoc_id);
3936 	if (!transport)
3937 		return -EINVAL;
3938 
3939 	pinfo.spinfo_assoc_id = sctp_assoc2id(transport->asoc);
3940 	pinfo.spinfo_state = transport->state;
3941 	pinfo.spinfo_cwnd = transport->cwnd;
3942 	pinfo.spinfo_srtt = transport->srtt;
3943 	pinfo.spinfo_rto = jiffies_to_msecs(transport->rto);
3944 	pinfo.spinfo_mtu = transport->pathmtu;
3945 
3946 	if (pinfo.spinfo_state == SCTP_UNKNOWN)
3947 		pinfo.spinfo_state = SCTP_ACTIVE;
3948 
3949 	if (put_user(len, optlen)) {
3950 		retval = -EFAULT;
3951 		goto out;
3952 	}
3953 
3954 	if (copy_to_user(optval, &pinfo, len)) {
3955 		retval = -EFAULT;
3956 		goto out;
3957 	}
3958 
3959 out:
3960 	return retval;
3961 }
3962 
3963 /* 7.1.12 Enable/Disable message fragmentation (SCTP_DISABLE_FRAGMENTS)
3964  *
3965  * This option is a on/off flag.  If enabled no SCTP message
3966  * fragmentation will be performed.  Instead if a message being sent
3967  * exceeds the current PMTU size, the message will NOT be sent and
3968  * instead a error will be indicated to the user.
3969  */
sctp_getsockopt_disable_fragments(struct sock * sk,int len,char __user * optval,int __user * optlen)3970 static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
3971 					char __user *optval, int __user *optlen)
3972 {
3973 	int val;
3974 
3975 	if (len < sizeof(int))
3976 		return -EINVAL;
3977 
3978 	len = sizeof(int);
3979 	val = (sctp_sk(sk)->disable_fragments == 1);
3980 	if (put_user(len, optlen))
3981 		return -EFAULT;
3982 	if (copy_to_user(optval, &val, len))
3983 		return -EFAULT;
3984 	return 0;
3985 }
3986 
3987 /* 7.1.15 Set notification and ancillary events (SCTP_EVENTS)
3988  *
3989  * This socket option is used to specify various notifications and
3990  * ancillary data the user wishes to receive.
3991  */
sctp_getsockopt_events(struct sock * sk,int len,char __user * optval,int __user * optlen)3992 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
3993 				  int __user *optlen)
3994 {
3995 	if (len < sizeof(struct sctp_event_subscribe))
3996 		return -EINVAL;
3997 	len = sizeof(struct sctp_event_subscribe);
3998 	if (put_user(len, optlen))
3999 		return -EFAULT;
4000 	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
4001 		return -EFAULT;
4002 	return 0;
4003 }
4004 
4005 /* 7.1.8 Automatic Close of associations (SCTP_AUTOCLOSE)
4006  *
4007  * This socket option is applicable to the UDP-style socket only.  When
4008  * set it will cause associations that are idle for more than the
4009  * specified number of seconds to automatically close.  An association
4010  * being idle is defined an association that has NOT sent or received
4011  * user data.  The special value of '0' indicates that no automatic
4012  * close of any associations should be performed.  The option expects an
4013  * integer defining the number of seconds of idle time before an
4014  * association is closed.
4015  */
sctp_getsockopt_autoclose(struct sock * sk,int len,char __user * optval,int __user * optlen)4016 static int sctp_getsockopt_autoclose(struct sock *sk, int len, char __user *optval, int __user *optlen)
4017 {
4018 	/* Applicable to UDP-style socket only */
4019 	if (sctp_style(sk, TCP))
4020 		return -EOPNOTSUPP;
4021 	if (len < sizeof(int))
4022 		return -EINVAL;
4023 	len = sizeof(int);
4024 	if (put_user(len, optlen))
4025 		return -EFAULT;
4026 	if (copy_to_user(optval, &sctp_sk(sk)->autoclose, sizeof(int)))
4027 		return -EFAULT;
4028 	return 0;
4029 }
4030 
4031 /* Helper routine to branch off an association to a new socket.  */
sctp_do_peeloff(struct sctp_association * asoc,struct socket ** sockp)4032 SCTP_STATIC int sctp_do_peeloff(struct sctp_association *asoc,
4033 				struct socket **sockp)
4034 {
4035 	struct sock *sk = asoc->base.sk;
4036 	struct socket *sock;
4037 	struct sctp_af *af;
4038 	int err = 0;
4039 
4040 	/* An association cannot be branched off from an already peeled-off
4041 	 * socket, nor is this supported for tcp style sockets.
4042 	 */
4043 	if (!sctp_style(sk, UDP))
4044 		return -EINVAL;
4045 
4046 	/* Create a new socket.  */
4047 	err = sock_create(sk->sk_family, SOCK_SEQPACKET, IPPROTO_SCTP, &sock);
4048 	if (err < 0)
4049 		return err;
4050 
4051 	sctp_copy_sock(sock->sk, sk, asoc);
4052 
4053 	/* Make peeled-off sockets more like 1-1 accepted sockets.
4054 	 * Set the daddr and initialize id to something more random
4055 	 */
4056 	af = sctp_get_af_specific(asoc->peer.primary_addr.sa.sa_family);
4057 	af->to_sk_daddr(&asoc->peer.primary_addr, sk);
4058 
4059 	/* Populate the fields of the newsk from the oldsk and migrate the
4060 	 * asoc to the newsk.
4061 	 */
4062 	sctp_sock_migrate(sk, sock->sk, asoc, SCTP_SOCKET_UDP_HIGH_BANDWIDTH);
4063 
4064 	*sockp = sock;
4065 
4066 	return err;
4067 }
4068 
sctp_getsockopt_peeloff(struct sock * sk,int len,char __user * optval,int __user * optlen)4069 static int sctp_getsockopt_peeloff(struct sock *sk, int len, char __user *optval, int __user *optlen)
4070 {
4071 	sctp_peeloff_arg_t peeloff;
4072 	struct socket *newsock;
4073 	int retval = 0;
4074 	struct sctp_association *asoc;
4075 
4076 	if (len < sizeof(sctp_peeloff_arg_t))
4077 		return -EINVAL;
4078 	len = sizeof(sctp_peeloff_arg_t);
4079 	if (copy_from_user(&peeloff, optval, len))
4080 		return -EFAULT;
4081 
4082 	asoc = sctp_id2assoc(sk, peeloff.associd);
4083 	if (!asoc) {
4084 		retval = -EINVAL;
4085 		goto out;
4086 	}
4087 
4088 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p\n", __func__, sk, asoc);
4089 
4090 	retval = sctp_do_peeloff(asoc, &newsock);
4091 	if (retval < 0)
4092 		goto out;
4093 
4094 	/* Map the socket to an unused fd that can be returned to the user.  */
4095 	retval = sock_map_fd(newsock, 0);
4096 	if (retval < 0) {
4097 		sock_release(newsock);
4098 		goto out;
4099 	}
4100 
4101 	SCTP_DEBUG_PRINTK("%s: sk: %p asoc: %p newsk: %p sd: %d\n",
4102 			  __func__, sk, asoc, newsock->sk, retval);
4103 
4104 	/* Return the fd mapped to the new socket.  */
4105 	peeloff.sd = retval;
4106 	if (put_user(len, optlen))
4107 		return -EFAULT;
4108 	if (copy_to_user(optval, &peeloff, len))
4109 		retval = -EFAULT;
4110 
4111 out:
4112 	return retval;
4113 }
4114 
4115 /* 7.1.13 Peer Address Parameters (SCTP_PEER_ADDR_PARAMS)
4116  *
4117  * Applications can enable or disable heartbeats for any peer address of
4118  * an association, modify an address's heartbeat interval, force a
4119  * heartbeat to be sent immediately, and adjust the address's maximum
4120  * number of retransmissions sent before an address is considered
4121  * unreachable.  The following structure is used to access and modify an
4122  * address's parameters:
4123  *
4124  *  struct sctp_paddrparams {
4125  *     sctp_assoc_t            spp_assoc_id;
4126  *     struct sockaddr_storage spp_address;
4127  *     uint32_t                spp_hbinterval;
4128  *     uint16_t                spp_pathmaxrxt;
4129  *     uint32_t                spp_pathmtu;
4130  *     uint32_t                spp_sackdelay;
4131  *     uint32_t                spp_flags;
4132  * };
4133  *
4134  *   spp_assoc_id    - (one-to-many style socket) This is filled in the
4135  *                     application, and identifies the association for
4136  *                     this query.
4137  *   spp_address     - This specifies which address is of interest.
4138  *   spp_hbinterval  - This contains the value of the heartbeat interval,
4139  *                     in milliseconds.  If a  value of zero
4140  *                     is present in this field then no changes are to
4141  *                     be made to this parameter.
4142  *   spp_pathmaxrxt  - This contains the maximum number of
4143  *                     retransmissions before this address shall be
4144  *                     considered unreachable. If a  value of zero
4145  *                     is present in this field then no changes are to
4146  *                     be made to this parameter.
4147  *   spp_pathmtu     - When Path MTU discovery is disabled the value
4148  *                     specified here will be the "fixed" path mtu.
4149  *                     Note that if the spp_address field is empty
4150  *                     then all associations on this address will
4151  *                     have this fixed path mtu set upon them.
4152  *
4153  *   spp_sackdelay   - When delayed sack is enabled, this value specifies
4154  *                     the number of milliseconds that sacks will be delayed
4155  *                     for. This value will apply to all addresses of an
4156  *                     association if the spp_address field is empty. Note
4157  *                     also, that if delayed sack is enabled and this
4158  *                     value is set to 0, no change is made to the last
4159  *                     recorded delayed sack timer value.
4160  *
4161  *   spp_flags       - These flags are used to control various features
4162  *                     on an association. The flag field may contain
4163  *                     zero or more of the following options.
4164  *
4165  *                     SPP_HB_ENABLE  - Enable heartbeats on the
4166  *                     specified address. Note that if the address
4167  *                     field is empty all addresses for the association
4168  *                     have heartbeats enabled upon them.
4169  *
4170  *                     SPP_HB_DISABLE - Disable heartbeats on the
4171  *                     speicifed address. Note that if the address
4172  *                     field is empty all addresses for the association
4173  *                     will have their heartbeats disabled. Note also
4174  *                     that SPP_HB_ENABLE and SPP_HB_DISABLE are
4175  *                     mutually exclusive, only one of these two should
4176  *                     be specified. Enabling both fields will have
4177  *                     undetermined results.
4178  *
4179  *                     SPP_HB_DEMAND - Request a user initiated heartbeat
4180  *                     to be made immediately.
4181  *
4182  *                     SPP_PMTUD_ENABLE - This field will enable PMTU
4183  *                     discovery upon the specified address. Note that
4184  *                     if the address feild is empty then all addresses
4185  *                     on the association are effected.
4186  *
4187  *                     SPP_PMTUD_DISABLE - This field will disable PMTU
4188  *                     discovery upon the specified address. Note that
4189  *                     if the address feild is empty then all addresses
4190  *                     on the association are effected. Not also that
4191  *                     SPP_PMTUD_ENABLE and SPP_PMTUD_DISABLE are mutually
4192  *                     exclusive. Enabling both will have undetermined
4193  *                     results.
4194  *
4195  *                     SPP_SACKDELAY_ENABLE - Setting this flag turns
4196  *                     on delayed sack. The time specified in spp_sackdelay
4197  *                     is used to specify the sack delay for this address. Note
4198  *                     that if spp_address is empty then all addresses will
4199  *                     enable delayed sack and take on the sack delay
4200  *                     value specified in spp_sackdelay.
4201  *                     SPP_SACKDELAY_DISABLE - Setting this flag turns
4202  *                     off delayed sack. If the spp_address field is blank then
4203  *                     delayed sack is disabled for the entire association. Note
4204  *                     also that this field is mutually exclusive to
4205  *                     SPP_SACKDELAY_ENABLE, setting both will have undefined
4206  *                     results.
4207  */
sctp_getsockopt_peer_addr_params(struct sock * sk,int len,char __user * optval,int __user * optlen)4208 static int sctp_getsockopt_peer_addr_params(struct sock *sk, int len,
4209 					    char __user *optval, int __user *optlen)
4210 {
4211 	struct sctp_paddrparams  params;
4212 	struct sctp_transport   *trans = NULL;
4213 	struct sctp_association *asoc = NULL;
4214 	struct sctp_sock        *sp = sctp_sk(sk);
4215 
4216 	if (len < sizeof(struct sctp_paddrparams))
4217 		return -EINVAL;
4218 	len = sizeof(struct sctp_paddrparams);
4219 	if (copy_from_user(&params, optval, len))
4220 		return -EFAULT;
4221 
4222 	/* If an address other than INADDR_ANY is specified, and
4223 	 * no transport is found, then the request is invalid.
4224 	 */
4225 	if (!sctp_is_any(sk, ( union sctp_addr *)&params.spp_address)) {
4226 		trans = sctp_addr_id2transport(sk, &params.spp_address,
4227 					       params.spp_assoc_id);
4228 		if (!trans) {
4229 			SCTP_DEBUG_PRINTK("Failed no transport\n");
4230 			return -EINVAL;
4231 		}
4232 	}
4233 
4234 	/* Get association, if assoc_id != 0 and the socket is a one
4235 	 * to many style socket, and an association was not found, then
4236 	 * the id was invalid.
4237 	 */
4238 	asoc = sctp_id2assoc(sk, params.spp_assoc_id);
4239 	if (!asoc && params.spp_assoc_id && sctp_style(sk, UDP)) {
4240 		SCTP_DEBUG_PRINTK("Failed no association\n");
4241 		return -EINVAL;
4242 	}
4243 
4244 	if (trans) {
4245 		/* Fetch transport values. */
4246 		params.spp_hbinterval = jiffies_to_msecs(trans->hbinterval);
4247 		params.spp_pathmtu    = trans->pathmtu;
4248 		params.spp_pathmaxrxt = trans->pathmaxrxt;
4249 		params.spp_sackdelay  = jiffies_to_msecs(trans->sackdelay);
4250 
4251 		/*draft-11 doesn't say what to return in spp_flags*/
4252 		params.spp_flags      = trans->param_flags;
4253 	} else if (asoc) {
4254 		/* Fetch association values. */
4255 		params.spp_hbinterval = jiffies_to_msecs(asoc->hbinterval);
4256 		params.spp_pathmtu    = asoc->pathmtu;
4257 		params.spp_pathmaxrxt = asoc->pathmaxrxt;
4258 		params.spp_sackdelay  = jiffies_to_msecs(asoc->sackdelay);
4259 
4260 		/*draft-11 doesn't say what to return in spp_flags*/
4261 		params.spp_flags      = asoc->param_flags;
4262 	} else {
4263 		/* Fetch socket values. */
4264 		params.spp_hbinterval = sp->hbinterval;
4265 		params.spp_pathmtu    = sp->pathmtu;
4266 		params.spp_sackdelay  = sp->sackdelay;
4267 		params.spp_pathmaxrxt = sp->pathmaxrxt;
4268 
4269 		/*draft-11 doesn't say what to return in spp_flags*/
4270 		params.spp_flags      = sp->param_flags;
4271 	}
4272 
4273 	if (copy_to_user(optval, &params, len))
4274 		return -EFAULT;
4275 
4276 	if (put_user(len, optlen))
4277 		return -EFAULT;
4278 
4279 	return 0;
4280 }
4281 
4282 /*
4283  * 7.1.23.  Get or set delayed ack timer (SCTP_DELAYED_SACK)
4284  *
4285  * This option will effect the way delayed acks are performed.  This
4286  * option allows you to get or set the delayed ack time, in
4287  * milliseconds.  It also allows changing the delayed ack frequency.
4288  * Changing the frequency to 1 disables the delayed sack algorithm.  If
4289  * the assoc_id is 0, then this sets or gets the endpoints default
4290  * values.  If the assoc_id field is non-zero, then the set or get
4291  * effects the specified association for the one to many model (the
4292  * assoc_id field is ignored by the one to one model).  Note that if
4293  * sack_delay or sack_freq are 0 when setting this option, then the
4294  * current values will remain unchanged.
4295  *
4296  * struct sctp_sack_info {
4297  *     sctp_assoc_t            sack_assoc_id;
4298  *     uint32_t                sack_delay;
4299  *     uint32_t                sack_freq;
4300  * };
4301  *
4302  * sack_assoc_id -  This parameter, indicates which association the user
4303  *    is performing an action upon.  Note that if this field's value is
4304  *    zero then the endpoints default value is changed (effecting future
4305  *    associations only).
4306  *
4307  * sack_delay -  This parameter contains the number of milliseconds that
4308  *    the user is requesting the delayed ACK timer be set to.  Note that
4309  *    this value is defined in the standard to be between 200 and 500
4310  *    milliseconds.
4311  *
4312  * sack_freq -  This parameter contains the number of packets that must
4313  *    be received before a sack is sent without waiting for the delay
4314  *    timer to expire.  The default value for this is 2, setting this
4315  *    value to 1 will disable the delayed sack algorithm.
4316  */
sctp_getsockopt_delayed_ack(struct sock * sk,int len,char __user * optval,int __user * optlen)4317 static int sctp_getsockopt_delayed_ack(struct sock *sk, int len,
4318 					    char __user *optval,
4319 					    int __user *optlen)
4320 {
4321 	struct sctp_sack_info    params;
4322 	struct sctp_association *asoc = NULL;
4323 	struct sctp_sock        *sp = sctp_sk(sk);
4324 
4325 	if (len >= sizeof(struct sctp_sack_info)) {
4326 		len = sizeof(struct sctp_sack_info);
4327 
4328 		if (copy_from_user(&params, optval, len))
4329 			return -EFAULT;
4330 	} else if (len == sizeof(struct sctp_assoc_value)) {
4331 		pr_warn("Use of struct sctp_assoc_value in delayed_ack socket option deprecated\n");
4332 		pr_warn("Use struct sctp_sack_info instead\n");
4333 		if (copy_from_user(&params, optval, len))
4334 			return -EFAULT;
4335 	} else
4336 		return - EINVAL;
4337 
4338 	/* Get association, if sack_assoc_id != 0 and the socket is a one
4339 	 * to many style socket, and an association was not found, then
4340 	 * the id was invalid.
4341 	 */
4342 	asoc = sctp_id2assoc(sk, params.sack_assoc_id);
4343 	if (!asoc && params.sack_assoc_id && sctp_style(sk, UDP))
4344 		return -EINVAL;
4345 
4346 	if (asoc) {
4347 		/* Fetch association values. */
4348 		if (asoc->param_flags & SPP_SACKDELAY_ENABLE) {
4349 			params.sack_delay = jiffies_to_msecs(
4350 				asoc->sackdelay);
4351 			params.sack_freq = asoc->sackfreq;
4352 
4353 		} else {
4354 			params.sack_delay = 0;
4355 			params.sack_freq = 1;
4356 		}
4357 	} else {
4358 		/* Fetch socket values. */
4359 		if (sp->param_flags & SPP_SACKDELAY_ENABLE) {
4360 			params.sack_delay  = sp->sackdelay;
4361 			params.sack_freq = sp->sackfreq;
4362 		} else {
4363 			params.sack_delay  = 0;
4364 			params.sack_freq = 1;
4365 		}
4366 	}
4367 
4368 	if (copy_to_user(optval, &params, len))
4369 		return -EFAULT;
4370 
4371 	if (put_user(len, optlen))
4372 		return -EFAULT;
4373 
4374 	return 0;
4375 }
4376 
4377 /* 7.1.3 Initialization Parameters (SCTP_INITMSG)
4378  *
4379  * Applications can specify protocol parameters for the default association
4380  * initialization.  The option name argument to setsockopt() and getsockopt()
4381  * is SCTP_INITMSG.
4382  *
4383  * Setting initialization parameters is effective only on an unconnected
4384  * socket (for UDP-style sockets only future associations are effected
4385  * by the change).  With TCP-style sockets, this option is inherited by
4386  * sockets derived from a listener socket.
4387  */
sctp_getsockopt_initmsg(struct sock * sk,int len,char __user * optval,int __user * optlen)4388 static int sctp_getsockopt_initmsg(struct sock *sk, int len, char __user *optval, int __user *optlen)
4389 {
4390 	if (len < sizeof(struct sctp_initmsg))
4391 		return -EINVAL;
4392 	len = sizeof(struct sctp_initmsg);
4393 	if (put_user(len, optlen))
4394 		return -EFAULT;
4395 	if (copy_to_user(optval, &sctp_sk(sk)->initmsg, len))
4396 		return -EFAULT;
4397 	return 0;
4398 }
4399 
4400 
sctp_getsockopt_peer_addrs(struct sock * sk,int len,char __user * optval,int __user * optlen)4401 static int sctp_getsockopt_peer_addrs(struct sock *sk, int len,
4402 				      char __user *optval, int __user *optlen)
4403 {
4404 	struct sctp_association *asoc;
4405 	int cnt = 0;
4406 	struct sctp_getaddrs getaddrs;
4407 	struct sctp_transport *from;
4408 	void __user *to;
4409 	union sctp_addr temp;
4410 	struct sctp_sock *sp = sctp_sk(sk);
4411 	int addrlen;
4412 	size_t space_left;
4413 	int bytes_copied;
4414 
4415 	if (len < sizeof(struct sctp_getaddrs))
4416 		return -EINVAL;
4417 
4418 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4419 		return -EFAULT;
4420 
4421 	/* For UDP-style sockets, id specifies the association to query.  */
4422 	asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4423 	if (!asoc)
4424 		return -EINVAL;
4425 
4426 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4427 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4428 
4429 	list_for_each_entry(from, &asoc->peer.transport_addr_list,
4430 				transports) {
4431 		memcpy(&temp, &from->ipaddr, sizeof(temp));
4432 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4433 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4434 		if (space_left < addrlen)
4435 			return -ENOMEM;
4436 		if (copy_to_user(to, &temp, addrlen))
4437 			return -EFAULT;
4438 		to += addrlen;
4439 		cnt++;
4440 		space_left -= addrlen;
4441 	}
4442 
4443 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num))
4444 		return -EFAULT;
4445 	bytes_copied = ((char __user *)to) - optval;
4446 	if (put_user(bytes_copied, optlen))
4447 		return -EFAULT;
4448 
4449 	return 0;
4450 }
4451 
sctp_copy_laddrs(struct sock * sk,__u16 port,void * to,size_t space_left,int * bytes_copied)4452 static int sctp_copy_laddrs(struct sock *sk, __u16 port, void *to,
4453 			    size_t space_left, int *bytes_copied)
4454 {
4455 	struct sctp_sockaddr_entry *addr;
4456 	union sctp_addr temp;
4457 	int cnt = 0;
4458 	int addrlen;
4459 
4460 	rcu_read_lock();
4461 	list_for_each_entry_rcu(addr, &sctp_local_addr_list, list) {
4462 		if (!addr->valid)
4463 			continue;
4464 
4465 		if ((PF_INET == sk->sk_family) &&
4466 		    (AF_INET6 == addr->a.sa.sa_family))
4467 			continue;
4468 		if ((PF_INET6 == sk->sk_family) &&
4469 		    inet_v6_ipv6only(sk) &&
4470 		    (AF_INET == addr->a.sa.sa_family))
4471 			continue;
4472 		memcpy(&temp, &addr->a, sizeof(temp));
4473 		if (!temp.v4.sin_port)
4474 			temp.v4.sin_port = htons(port);
4475 
4476 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sctp_sk(sk),
4477 								&temp);
4478 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4479 		if (space_left < addrlen) {
4480 			cnt =  -ENOMEM;
4481 			break;
4482 		}
4483 		memcpy(to, &temp, addrlen);
4484 
4485 		to += addrlen;
4486 		cnt ++;
4487 		space_left -= addrlen;
4488 		*bytes_copied += addrlen;
4489 	}
4490 	rcu_read_unlock();
4491 
4492 	return cnt;
4493 }
4494 
4495 
sctp_getsockopt_local_addrs(struct sock * sk,int len,char __user * optval,int __user * optlen)4496 static int sctp_getsockopt_local_addrs(struct sock *sk, int len,
4497 				       char __user *optval, int __user *optlen)
4498 {
4499 	struct sctp_bind_addr *bp;
4500 	struct sctp_association *asoc;
4501 	int cnt = 0;
4502 	struct sctp_getaddrs getaddrs;
4503 	struct sctp_sockaddr_entry *addr;
4504 	void __user *to;
4505 	union sctp_addr temp;
4506 	struct sctp_sock *sp = sctp_sk(sk);
4507 	int addrlen;
4508 	int err = 0;
4509 	size_t space_left;
4510 	int bytes_copied = 0;
4511 	void *addrs;
4512 	void *buf;
4513 
4514 	if (len < sizeof(struct sctp_getaddrs))
4515 		return -EINVAL;
4516 
4517 	if (copy_from_user(&getaddrs, optval, sizeof(struct sctp_getaddrs)))
4518 		return -EFAULT;
4519 
4520 	/*
4521 	 *  For UDP-style sockets, id specifies the association to query.
4522 	 *  If the id field is set to the value '0' then the locally bound
4523 	 *  addresses are returned without regard to any particular
4524 	 *  association.
4525 	 */
4526 	if (0 == getaddrs.assoc_id) {
4527 		bp = &sctp_sk(sk)->ep->base.bind_addr;
4528 	} else {
4529 		asoc = sctp_id2assoc(sk, getaddrs.assoc_id);
4530 		if (!asoc)
4531 			return -EINVAL;
4532 		bp = &asoc->base.bind_addr;
4533 	}
4534 
4535 	to = optval + offsetof(struct sctp_getaddrs,addrs);
4536 	space_left = len - offsetof(struct sctp_getaddrs,addrs);
4537 
4538 	addrs = kmalloc(space_left, GFP_KERNEL);
4539 	if (!addrs)
4540 		return -ENOMEM;
4541 
4542 	/* If the endpoint is bound to 0.0.0.0 or ::0, get the valid
4543 	 * addresses from the global local address list.
4544 	 */
4545 	if (sctp_list_single_entry(&bp->address_list)) {
4546 		addr = list_entry(bp->address_list.next,
4547 				  struct sctp_sockaddr_entry, list);
4548 		if (sctp_is_any(sk, &addr->a)) {
4549 			cnt = sctp_copy_laddrs(sk, bp->port, addrs,
4550 						space_left, &bytes_copied);
4551 			if (cnt < 0) {
4552 				err = cnt;
4553 				goto out;
4554 			}
4555 			goto copy_getaddrs;
4556 		}
4557 	}
4558 
4559 	buf = addrs;
4560 	/* Protection on the bound address list is not needed since
4561 	 * in the socket option context we hold a socket lock and
4562 	 * thus the bound address list can't change.
4563 	 */
4564 	list_for_each_entry(addr, &bp->address_list, list) {
4565 		memcpy(&temp, &addr->a, sizeof(temp));
4566 		sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp, &temp);
4567 		addrlen = sctp_get_af_specific(temp.sa.sa_family)->sockaddr_len;
4568 		if (space_left < addrlen) {
4569 			err =  -ENOMEM; /*fixme: right error?*/
4570 			goto out;
4571 		}
4572 		memcpy(buf, &temp, addrlen);
4573 		buf += addrlen;
4574 		bytes_copied += addrlen;
4575 		cnt ++;
4576 		space_left -= addrlen;
4577 	}
4578 
4579 copy_getaddrs:
4580 	if (copy_to_user(to, addrs, bytes_copied)) {
4581 		err = -EFAULT;
4582 		goto out;
4583 	}
4584 	if (put_user(cnt, &((struct sctp_getaddrs __user *)optval)->addr_num)) {
4585 		err = -EFAULT;
4586 		goto out;
4587 	}
4588 	if (put_user(bytes_copied, optlen))
4589 		err = -EFAULT;
4590 out:
4591 	kfree(addrs);
4592 	return err;
4593 }
4594 
4595 /* 7.1.10 Set Primary Address (SCTP_PRIMARY_ADDR)
4596  *
4597  * Requests that the local SCTP stack use the enclosed peer address as
4598  * the association primary.  The enclosed address must be one of the
4599  * association peer's addresses.
4600  */
sctp_getsockopt_primary_addr(struct sock * sk,int len,char __user * optval,int __user * optlen)4601 static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
4602 					char __user *optval, int __user *optlen)
4603 {
4604 	struct sctp_prim prim;
4605 	struct sctp_association *asoc;
4606 	struct sctp_sock *sp = sctp_sk(sk);
4607 
4608 	if (len < sizeof(struct sctp_prim))
4609 		return -EINVAL;
4610 
4611 	len = sizeof(struct sctp_prim);
4612 
4613 	if (copy_from_user(&prim, optval, len))
4614 		return -EFAULT;
4615 
4616 	asoc = sctp_id2assoc(sk, prim.ssp_assoc_id);
4617 	if (!asoc)
4618 		return -EINVAL;
4619 
4620 	if (!asoc->peer.primary_path)
4621 		return -ENOTCONN;
4622 
4623 	memcpy(&prim.ssp_addr, &asoc->peer.primary_path->ipaddr,
4624 		asoc->peer.primary_path->af_specific->sockaddr_len);
4625 
4626 	sctp_get_pf_specific(sk->sk_family)->addr_v4map(sp,
4627 			(union sctp_addr *)&prim.ssp_addr);
4628 
4629 	if (put_user(len, optlen))
4630 		return -EFAULT;
4631 	if (copy_to_user(optval, &prim, len))
4632 		return -EFAULT;
4633 
4634 	return 0;
4635 }
4636 
4637 /*
4638  * 7.1.11  Set Adaptation Layer Indicator (SCTP_ADAPTATION_LAYER)
4639  *
4640  * Requests that the local endpoint set the specified Adaptation Layer
4641  * Indication parameter for all future INIT and INIT-ACK exchanges.
4642  */
sctp_getsockopt_adaptation_layer(struct sock * sk,int len,char __user * optval,int __user * optlen)4643 static int sctp_getsockopt_adaptation_layer(struct sock *sk, int len,
4644 				  char __user *optval, int __user *optlen)
4645 {
4646 	struct sctp_setadaptation adaptation;
4647 
4648 	if (len < sizeof(struct sctp_setadaptation))
4649 		return -EINVAL;
4650 
4651 	len = sizeof(struct sctp_setadaptation);
4652 
4653 	adaptation.ssb_adaptation_ind = sctp_sk(sk)->adaptation_ind;
4654 
4655 	if (put_user(len, optlen))
4656 		return -EFAULT;
4657 	if (copy_to_user(optval, &adaptation, len))
4658 		return -EFAULT;
4659 
4660 	return 0;
4661 }
4662 
4663 /*
4664  *
4665  * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
4666  *
4667  *   Applications that wish to use the sendto() system call may wish to
4668  *   specify a default set of parameters that would normally be supplied
4669  *   through the inclusion of ancillary data.  This socket option allows
4670  *   such an application to set the default sctp_sndrcvinfo structure.
4671 
4672 
4673  *   The application that wishes to use this socket option simply passes
4674  *   in to this call the sctp_sndrcvinfo structure defined in Section
4675  *   5.2.2) The input parameters accepted by this call include
4676  *   sinfo_stream, sinfo_flags, sinfo_ppid, sinfo_context,
4677  *   sinfo_timetolive.  The user must provide the sinfo_assoc_id field in
4678  *   to this call if the caller is using the UDP model.
4679  *
4680  *   For getsockopt, it get the default sctp_sndrcvinfo structure.
4681  */
sctp_getsockopt_default_send_param(struct sock * sk,int len,char __user * optval,int __user * optlen)4682 static int sctp_getsockopt_default_send_param(struct sock *sk,
4683 					int len, char __user *optval,
4684 					int __user *optlen)
4685 {
4686 	struct sctp_sndrcvinfo info;
4687 	struct sctp_association *asoc;
4688 	struct sctp_sock *sp = sctp_sk(sk);
4689 
4690 	if (len < sizeof(struct sctp_sndrcvinfo))
4691 		return -EINVAL;
4692 
4693 	len = sizeof(struct sctp_sndrcvinfo);
4694 
4695 	if (copy_from_user(&info, optval, len))
4696 		return -EFAULT;
4697 
4698 	asoc = sctp_id2assoc(sk, info.sinfo_assoc_id);
4699 	if (!asoc && info.sinfo_assoc_id && sctp_style(sk, UDP))
4700 		return -EINVAL;
4701 
4702 	if (asoc) {
4703 		info.sinfo_stream = asoc->default_stream;
4704 		info.sinfo_flags = asoc->default_flags;
4705 		info.sinfo_ppid = asoc->default_ppid;
4706 		info.sinfo_context = asoc->default_context;
4707 		info.sinfo_timetolive = asoc->default_timetolive;
4708 	} else {
4709 		info.sinfo_stream = sp->default_stream;
4710 		info.sinfo_flags = sp->default_flags;
4711 		info.sinfo_ppid = sp->default_ppid;
4712 		info.sinfo_context = sp->default_context;
4713 		info.sinfo_timetolive = sp->default_timetolive;
4714 	}
4715 
4716 	if (put_user(len, optlen))
4717 		return -EFAULT;
4718 	if (copy_to_user(optval, &info, len))
4719 		return -EFAULT;
4720 
4721 	return 0;
4722 }
4723 
4724 /*
4725  *
4726  * 7.1.5 SCTP_NODELAY
4727  *
4728  * Turn on/off any Nagle-like algorithm.  This means that packets are
4729  * generally sent as soon as possible and no unnecessary delays are
4730  * introduced, at the cost of more packets in the network.  Expects an
4731  * integer boolean flag.
4732  */
4733 
sctp_getsockopt_nodelay(struct sock * sk,int len,char __user * optval,int __user * optlen)4734 static int sctp_getsockopt_nodelay(struct sock *sk, int len,
4735 				   char __user *optval, int __user *optlen)
4736 {
4737 	int val;
4738 
4739 	if (len < sizeof(int))
4740 		return -EINVAL;
4741 
4742 	len = sizeof(int);
4743 	val = (sctp_sk(sk)->nodelay == 1);
4744 	if (put_user(len, optlen))
4745 		return -EFAULT;
4746 	if (copy_to_user(optval, &val, len))
4747 		return -EFAULT;
4748 	return 0;
4749 }
4750 
4751 /*
4752  *
4753  * 7.1.1 SCTP_RTOINFO
4754  *
4755  * The protocol parameters used to initialize and bound retransmission
4756  * timeout (RTO) are tunable. sctp_rtoinfo structure is used to access
4757  * and modify these parameters.
4758  * All parameters are time values, in milliseconds.  A value of 0, when
4759  * modifying the parameters, indicates that the current value should not
4760  * be changed.
4761  *
4762  */
sctp_getsockopt_rtoinfo(struct sock * sk,int len,char __user * optval,int __user * optlen)4763 static int sctp_getsockopt_rtoinfo(struct sock *sk, int len,
4764 				char __user *optval,
4765 				int __user *optlen) {
4766 	struct sctp_rtoinfo rtoinfo;
4767 	struct sctp_association *asoc;
4768 
4769 	if (len < sizeof (struct sctp_rtoinfo))
4770 		return -EINVAL;
4771 
4772 	len = sizeof(struct sctp_rtoinfo);
4773 
4774 	if (copy_from_user(&rtoinfo, optval, len))
4775 		return -EFAULT;
4776 
4777 	asoc = sctp_id2assoc(sk, rtoinfo.srto_assoc_id);
4778 
4779 	if (!asoc && rtoinfo.srto_assoc_id && sctp_style(sk, UDP))
4780 		return -EINVAL;
4781 
4782 	/* Values corresponding to the specific association. */
4783 	if (asoc) {
4784 		rtoinfo.srto_initial = jiffies_to_msecs(asoc->rto_initial);
4785 		rtoinfo.srto_max = jiffies_to_msecs(asoc->rto_max);
4786 		rtoinfo.srto_min = jiffies_to_msecs(asoc->rto_min);
4787 	} else {
4788 		/* Values corresponding to the endpoint. */
4789 		struct sctp_sock *sp = sctp_sk(sk);
4790 
4791 		rtoinfo.srto_initial = sp->rtoinfo.srto_initial;
4792 		rtoinfo.srto_max = sp->rtoinfo.srto_max;
4793 		rtoinfo.srto_min = sp->rtoinfo.srto_min;
4794 	}
4795 
4796 	if (put_user(len, optlen))
4797 		return -EFAULT;
4798 
4799 	if (copy_to_user(optval, &rtoinfo, len))
4800 		return -EFAULT;
4801 
4802 	return 0;
4803 }
4804 
4805 /*
4806  *
4807  * 7.1.2 SCTP_ASSOCINFO
4808  *
4809  * This option is used to tune the maximum retransmission attempts
4810  * of the association.
4811  * Returns an error if the new association retransmission value is
4812  * greater than the sum of the retransmission value  of the peer.
4813  * See [SCTP] for more information.
4814  *
4815  */
sctp_getsockopt_associnfo(struct sock * sk,int len,char __user * optval,int __user * optlen)4816 static int sctp_getsockopt_associnfo(struct sock *sk, int len,
4817 				     char __user *optval,
4818 				     int __user *optlen)
4819 {
4820 
4821 	struct sctp_assocparams assocparams;
4822 	struct sctp_association *asoc;
4823 	struct list_head *pos;
4824 	int cnt = 0;
4825 
4826 	if (len < sizeof (struct sctp_assocparams))
4827 		return -EINVAL;
4828 
4829 	len = sizeof(struct sctp_assocparams);
4830 
4831 	if (copy_from_user(&assocparams, optval, len))
4832 		return -EFAULT;
4833 
4834 	asoc = sctp_id2assoc(sk, assocparams.sasoc_assoc_id);
4835 
4836 	if (!asoc && assocparams.sasoc_assoc_id && sctp_style(sk, UDP))
4837 		return -EINVAL;
4838 
4839 	/* Values correspoinding to the specific association */
4840 	if (asoc) {
4841 		assocparams.sasoc_asocmaxrxt = asoc->max_retrans;
4842 		assocparams.sasoc_peer_rwnd = asoc->peer.rwnd;
4843 		assocparams.sasoc_local_rwnd = asoc->a_rwnd;
4844 		assocparams.sasoc_cookie_life = (asoc->cookie_life.tv_sec
4845 						* 1000) +
4846 						(asoc->cookie_life.tv_usec
4847 						/ 1000);
4848 
4849 		list_for_each(pos, &asoc->peer.transport_addr_list) {
4850 			cnt ++;
4851 		}
4852 
4853 		assocparams.sasoc_number_peer_destinations = cnt;
4854 	} else {
4855 		/* Values corresponding to the endpoint */
4856 		struct sctp_sock *sp = sctp_sk(sk);
4857 
4858 		assocparams.sasoc_asocmaxrxt = sp->assocparams.sasoc_asocmaxrxt;
4859 		assocparams.sasoc_peer_rwnd = sp->assocparams.sasoc_peer_rwnd;
4860 		assocparams.sasoc_local_rwnd = sp->assocparams.sasoc_local_rwnd;
4861 		assocparams.sasoc_cookie_life =
4862 					sp->assocparams.sasoc_cookie_life;
4863 		assocparams.sasoc_number_peer_destinations =
4864 					sp->assocparams.
4865 					sasoc_number_peer_destinations;
4866 	}
4867 
4868 	if (put_user(len, optlen))
4869 		return -EFAULT;
4870 
4871 	if (copy_to_user(optval, &assocparams, len))
4872 		return -EFAULT;
4873 
4874 	return 0;
4875 }
4876 
4877 /*
4878  * 7.1.16 Set/clear IPv4 mapped addresses (SCTP_I_WANT_MAPPED_V4_ADDR)
4879  *
4880  * This socket option is a boolean flag which turns on or off mapped V4
4881  * addresses.  If this option is turned on and the socket is type
4882  * PF_INET6, then IPv4 addresses will be mapped to V6 representation.
4883  * If this option is turned off, then no mapping will be done of V4
4884  * addresses and a user will receive both PF_INET6 and PF_INET type
4885  * addresses on the socket.
4886  */
sctp_getsockopt_mappedv4(struct sock * sk,int len,char __user * optval,int __user * optlen)4887 static int sctp_getsockopt_mappedv4(struct sock *sk, int len,
4888 				    char __user *optval, int __user *optlen)
4889 {
4890 	int val;
4891 	struct sctp_sock *sp = sctp_sk(sk);
4892 
4893 	if (len < sizeof(int))
4894 		return -EINVAL;
4895 
4896 	len = sizeof(int);
4897 	val = sp->v4mapped;
4898 	if (put_user(len, optlen))
4899 		return -EFAULT;
4900 	if (copy_to_user(optval, &val, len))
4901 		return -EFAULT;
4902 
4903 	return 0;
4904 }
4905 
4906 /*
4907  * 7.1.29.  Set or Get the default context (SCTP_CONTEXT)
4908  * (chapter and verse is quoted at sctp_setsockopt_context())
4909  */
sctp_getsockopt_context(struct sock * sk,int len,char __user * optval,int __user * optlen)4910 static int sctp_getsockopt_context(struct sock *sk, int len,
4911 				   char __user *optval, int __user *optlen)
4912 {
4913 	struct sctp_assoc_value params;
4914 	struct sctp_sock *sp;
4915 	struct sctp_association *asoc;
4916 
4917 	if (len < sizeof(struct sctp_assoc_value))
4918 		return -EINVAL;
4919 
4920 	len = sizeof(struct sctp_assoc_value);
4921 
4922 	if (copy_from_user(&params, optval, len))
4923 		return -EFAULT;
4924 
4925 	sp = sctp_sk(sk);
4926 
4927 	if (params.assoc_id != 0) {
4928 		asoc = sctp_id2assoc(sk, params.assoc_id);
4929 		if (!asoc)
4930 			return -EINVAL;
4931 		params.assoc_value = asoc->default_rcv_context;
4932 	} else {
4933 		params.assoc_value = sp->default_rcv_context;
4934 	}
4935 
4936 	if (put_user(len, optlen))
4937 		return -EFAULT;
4938 	if (copy_to_user(optval, &params, len))
4939 		return -EFAULT;
4940 
4941 	return 0;
4942 }
4943 
4944 /*
4945  * 8.1.16.  Get or Set the Maximum Fragmentation Size (SCTP_MAXSEG)
4946  * This option will get or set the maximum size to put in any outgoing
4947  * SCTP DATA chunk.  If a message is larger than this size it will be
4948  * fragmented by SCTP into the specified size.  Note that the underlying
4949  * SCTP implementation may fragment into smaller sized chunks when the
4950  * PMTU of the underlying association is smaller than the value set by
4951  * the user.  The default value for this option is '0' which indicates
4952  * the user is NOT limiting fragmentation and only the PMTU will effect
4953  * SCTP's choice of DATA chunk size.  Note also that values set larger
4954  * than the maximum size of an IP datagram will effectively let SCTP
4955  * control fragmentation (i.e. the same as setting this option to 0).
4956  *
4957  * The following structure is used to access and modify this parameter:
4958  *
4959  * struct sctp_assoc_value {
4960  *   sctp_assoc_t assoc_id;
4961  *   uint32_t assoc_value;
4962  * };
4963  *
4964  * assoc_id:  This parameter is ignored for one-to-one style sockets.
4965  *    For one-to-many style sockets this parameter indicates which
4966  *    association the user is performing an action upon.  Note that if
4967  *    this field's value is zero then the endpoints default value is
4968  *    changed (effecting future associations only).
4969  * assoc_value:  This parameter specifies the maximum size in bytes.
4970  */
sctp_getsockopt_maxseg(struct sock * sk,int len,char __user * optval,int __user * optlen)4971 static int sctp_getsockopt_maxseg(struct sock *sk, int len,
4972 				  char __user *optval, int __user *optlen)
4973 {
4974 	struct sctp_assoc_value params;
4975 	struct sctp_association *asoc;
4976 
4977 	if (len == sizeof(int)) {
4978 		pr_warn("Use of int in maxseg socket option deprecated\n");
4979 		pr_warn("Use struct sctp_assoc_value instead\n");
4980 		params.assoc_id = 0;
4981 	} else if (len >= sizeof(struct sctp_assoc_value)) {
4982 		len = sizeof(struct sctp_assoc_value);
4983 		if (copy_from_user(&params, optval, sizeof(params)))
4984 			return -EFAULT;
4985 	} else
4986 		return -EINVAL;
4987 
4988 	asoc = sctp_id2assoc(sk, params.assoc_id);
4989 	if (!asoc && params.assoc_id && sctp_style(sk, UDP))
4990 		return -EINVAL;
4991 
4992 	if (asoc)
4993 		params.assoc_value = asoc->frag_point;
4994 	else
4995 		params.assoc_value = sctp_sk(sk)->user_frag;
4996 
4997 	if (put_user(len, optlen))
4998 		return -EFAULT;
4999 	if (len == sizeof(int)) {
5000 		if (copy_to_user(optval, &params.assoc_value, len))
5001 			return -EFAULT;
5002 	} else {
5003 		if (copy_to_user(optval, &params, len))
5004 			return -EFAULT;
5005 	}
5006 
5007 	return 0;
5008 }
5009 
5010 /*
5011  * 7.1.24.  Get or set fragmented interleave (SCTP_FRAGMENT_INTERLEAVE)
5012  * (chapter and verse is quoted at sctp_setsockopt_fragment_interleave())
5013  */
sctp_getsockopt_fragment_interleave(struct sock * sk,int len,char __user * optval,int __user * optlen)5014 static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
5015 					       char __user *optval, int __user *optlen)
5016 {
5017 	int val;
5018 
5019 	if (len < sizeof(int))
5020 		return -EINVAL;
5021 
5022 	len = sizeof(int);
5023 
5024 	val = sctp_sk(sk)->frag_interleave;
5025 	if (put_user(len, optlen))
5026 		return -EFAULT;
5027 	if (copy_to_user(optval, &val, len))
5028 		return -EFAULT;
5029 
5030 	return 0;
5031 }
5032 
5033 /*
5034  * 7.1.25.  Set or Get the sctp partial delivery point
5035  * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
5036  */
sctp_getsockopt_partial_delivery_point(struct sock * sk,int len,char __user * optval,int __user * optlen)5037 static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
5038 						  char __user *optval,
5039 						  int __user *optlen)
5040 {
5041 	u32 val;
5042 
5043 	if (len < sizeof(u32))
5044 		return -EINVAL;
5045 
5046 	len = sizeof(u32);
5047 
5048 	val = sctp_sk(sk)->pd_point;
5049 	if (put_user(len, optlen))
5050 		return -EFAULT;
5051 	if (copy_to_user(optval, &val, len))
5052 		return -EFAULT;
5053 
5054 	return 0;
5055 }
5056 
5057 /*
5058  * 7.1.28.  Set or Get the maximum burst (SCTP_MAX_BURST)
5059  * (chapter and verse is quoted at sctp_setsockopt_maxburst())
5060  */
sctp_getsockopt_maxburst(struct sock * sk,int len,char __user * optval,int __user * optlen)5061 static int sctp_getsockopt_maxburst(struct sock *sk, int len,
5062 				    char __user *optval,
5063 				    int __user *optlen)
5064 {
5065 	struct sctp_assoc_value params;
5066 	struct sctp_sock *sp;
5067 	struct sctp_association *asoc;
5068 
5069 	if (len == sizeof(int)) {
5070 		pr_warn("Use of int in max_burst socket option deprecated\n");
5071 		pr_warn("Use struct sctp_assoc_value instead\n");
5072 		params.assoc_id = 0;
5073 	} else if (len >= sizeof(struct sctp_assoc_value)) {
5074 		len = sizeof(struct sctp_assoc_value);
5075 		if (copy_from_user(&params, optval, len))
5076 			return -EFAULT;
5077 	} else
5078 		return -EINVAL;
5079 
5080 	sp = sctp_sk(sk);
5081 
5082 	if (params.assoc_id != 0) {
5083 		asoc = sctp_id2assoc(sk, params.assoc_id);
5084 		if (!asoc)
5085 			return -EINVAL;
5086 		params.assoc_value = asoc->max_burst;
5087 	} else
5088 		params.assoc_value = sp->max_burst;
5089 
5090 	if (len == sizeof(int)) {
5091 		if (copy_to_user(optval, &params.assoc_value, len))
5092 			return -EFAULT;
5093 	} else {
5094 		if (copy_to_user(optval, &params, len))
5095 			return -EFAULT;
5096 	}
5097 
5098 	return 0;
5099 
5100 }
5101 
sctp_getsockopt_hmac_ident(struct sock * sk,int len,char __user * optval,int __user * optlen)5102 static int sctp_getsockopt_hmac_ident(struct sock *sk, int len,
5103 				    char __user *optval, int __user *optlen)
5104 {
5105 	struct sctp_hmacalgo  __user *p = (void __user *)optval;
5106 	struct sctp_hmac_algo_param *hmacs;
5107 	__u16 data_len = 0;
5108 	u32 num_idents;
5109 
5110 	if (!sctp_auth_enable)
5111 		return -EACCES;
5112 
5113 	hmacs = sctp_sk(sk)->ep->auth_hmacs_list;
5114 	data_len = ntohs(hmacs->param_hdr.length) - sizeof(sctp_paramhdr_t);
5115 
5116 	if (len < sizeof(struct sctp_hmacalgo) + data_len)
5117 		return -EINVAL;
5118 
5119 	len = sizeof(struct sctp_hmacalgo) + data_len;
5120 	num_idents = data_len / sizeof(u16);
5121 
5122 	if (put_user(len, optlen))
5123 		return -EFAULT;
5124 	if (put_user(num_idents, &p->shmac_num_idents))
5125 		return -EFAULT;
5126 	if (copy_to_user(p->shmac_idents, hmacs->hmac_ids, data_len))
5127 		return -EFAULT;
5128 	return 0;
5129 }
5130 
sctp_getsockopt_active_key(struct sock * sk,int len,char __user * optval,int __user * optlen)5131 static int sctp_getsockopt_active_key(struct sock *sk, int len,
5132 				    char __user *optval, int __user *optlen)
5133 {
5134 	struct sctp_authkeyid val;
5135 	struct sctp_association *asoc;
5136 
5137 	if (!sctp_auth_enable)
5138 		return -EACCES;
5139 
5140 	if (len < sizeof(struct sctp_authkeyid))
5141 		return -EINVAL;
5142 	if (copy_from_user(&val, optval, sizeof(struct sctp_authkeyid)))
5143 		return -EFAULT;
5144 
5145 	asoc = sctp_id2assoc(sk, val.scact_assoc_id);
5146 	if (!asoc && val.scact_assoc_id && sctp_style(sk, UDP))
5147 		return -EINVAL;
5148 
5149 	if (asoc)
5150 		val.scact_keynumber = asoc->active_key_id;
5151 	else
5152 		val.scact_keynumber = sctp_sk(sk)->ep->active_key_id;
5153 
5154 	len = sizeof(struct sctp_authkeyid);
5155 	if (put_user(len, optlen))
5156 		return -EFAULT;
5157 	if (copy_to_user(optval, &val, len))
5158 		return -EFAULT;
5159 
5160 	return 0;
5161 }
5162 
sctp_getsockopt_peer_auth_chunks(struct sock * sk,int len,char __user * optval,int __user * optlen)5163 static int sctp_getsockopt_peer_auth_chunks(struct sock *sk, int len,
5164 				    char __user *optval, int __user *optlen)
5165 {
5166 	struct sctp_authchunks __user *p = (void __user *)optval;
5167 	struct sctp_authchunks val;
5168 	struct sctp_association *asoc;
5169 	struct sctp_chunks_param *ch;
5170 	u32    num_chunks = 0;
5171 	char __user *to;
5172 
5173 	if (!sctp_auth_enable)
5174 		return -EACCES;
5175 
5176 	if (len < sizeof(struct sctp_authchunks))
5177 		return -EINVAL;
5178 
5179 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5180 		return -EFAULT;
5181 
5182 	to = p->gauth_chunks;
5183 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5184 	if (!asoc)
5185 		return -EINVAL;
5186 
5187 	ch = asoc->peer.peer_chunks;
5188 	if (!ch)
5189 		goto num;
5190 
5191 	/* See if the user provided enough room for all the data */
5192 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5193 	if (len < num_chunks)
5194 		return -EINVAL;
5195 
5196 	if (copy_to_user(to, ch->chunks, num_chunks))
5197 		return -EFAULT;
5198 num:
5199 	len = sizeof(struct sctp_authchunks) + num_chunks;
5200 	if (put_user(len, optlen)) return -EFAULT;
5201 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
5202 		return -EFAULT;
5203 	return 0;
5204 }
5205 
sctp_getsockopt_local_auth_chunks(struct sock * sk,int len,char __user * optval,int __user * optlen)5206 static int sctp_getsockopt_local_auth_chunks(struct sock *sk, int len,
5207 				    char __user *optval, int __user *optlen)
5208 {
5209 	struct sctp_authchunks __user *p = (void __user *)optval;
5210 	struct sctp_authchunks val;
5211 	struct sctp_association *asoc;
5212 	struct sctp_chunks_param *ch;
5213 	u32    num_chunks = 0;
5214 	char __user *to;
5215 
5216 	if (!sctp_auth_enable)
5217 		return -EACCES;
5218 
5219 	if (len < sizeof(struct sctp_authchunks))
5220 		return -EINVAL;
5221 
5222 	if (copy_from_user(&val, optval, sizeof(struct sctp_authchunks)))
5223 		return -EFAULT;
5224 
5225 	to = p->gauth_chunks;
5226 	asoc = sctp_id2assoc(sk, val.gauth_assoc_id);
5227 	if (!asoc && val.gauth_assoc_id && sctp_style(sk, UDP))
5228 		return -EINVAL;
5229 
5230 	if (asoc)
5231 		ch = (struct sctp_chunks_param*)asoc->c.auth_chunks;
5232 	else
5233 		ch = sctp_sk(sk)->ep->auth_chunk_list;
5234 
5235 	if (!ch)
5236 		goto num;
5237 
5238 	num_chunks = ntohs(ch->param_hdr.length) - sizeof(sctp_paramhdr_t);
5239 	if (len < sizeof(struct sctp_authchunks) + num_chunks)
5240 		return -EINVAL;
5241 
5242 	if (copy_to_user(to, ch->chunks, num_chunks))
5243 		return -EFAULT;
5244 num:
5245 	len = sizeof(struct sctp_authchunks) + num_chunks;
5246 	if (put_user(len, optlen))
5247 		return -EFAULT;
5248 	if (put_user(num_chunks, &p->gauth_number_of_chunks))
5249 		return -EFAULT;
5250 
5251 	return 0;
5252 }
5253 
5254 /*
5255  * 8.2.5.  Get the Current Number of Associations (SCTP_GET_ASSOC_NUMBER)
5256  * This option gets the current number of associations that are attached
5257  * to a one-to-many style socket.  The option value is an uint32_t.
5258  */
sctp_getsockopt_assoc_number(struct sock * sk,int len,char __user * optval,int __user * optlen)5259 static int sctp_getsockopt_assoc_number(struct sock *sk, int len,
5260 				    char __user *optval, int __user *optlen)
5261 {
5262 	struct sctp_sock *sp = sctp_sk(sk);
5263 	struct sctp_association *asoc;
5264 	u32 val = 0;
5265 
5266 	if (sctp_style(sk, TCP))
5267 		return -EOPNOTSUPP;
5268 
5269 	if (len < sizeof(u32))
5270 		return -EINVAL;
5271 
5272 	len = sizeof(u32);
5273 
5274 	list_for_each_entry(asoc, &(sp->ep->asocs), asocs) {
5275 		val++;
5276 	}
5277 
5278 	if (put_user(len, optlen))
5279 		return -EFAULT;
5280 	if (copy_to_user(optval, &val, len))
5281 		return -EFAULT;
5282 
5283 	return 0;
5284 }
5285 
sctp_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * optlen)5286 SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
5287 				char __user *optval, int __user *optlen)
5288 {
5289 	int retval = 0;
5290 	int len;
5291 
5292 	SCTP_DEBUG_PRINTK("sctp_getsockopt(sk: %p... optname: %d)\n",
5293 			  sk, optname);
5294 
5295 	/* I can hardly begin to describe how wrong this is.  This is
5296 	 * so broken as to be worse than useless.  The API draft
5297 	 * REALLY is NOT helpful here...  I am not convinced that the
5298 	 * semantics of getsockopt() with a level OTHER THAN SOL_SCTP
5299 	 * are at all well-founded.
5300 	 */
5301 	if (level != SOL_SCTP) {
5302 		struct sctp_af *af = sctp_sk(sk)->pf->af;
5303 
5304 		retval = af->getsockopt(sk, level, optname, optval, optlen);
5305 		return retval;
5306 	}
5307 
5308 	if (get_user(len, optlen))
5309 		return -EFAULT;
5310 
5311 	sctp_lock_sock(sk);
5312 
5313 	switch (optname) {
5314 	case SCTP_STATUS:
5315 		retval = sctp_getsockopt_sctp_status(sk, len, optval, optlen);
5316 		break;
5317 	case SCTP_DISABLE_FRAGMENTS:
5318 		retval = sctp_getsockopt_disable_fragments(sk, len, optval,
5319 							   optlen);
5320 		break;
5321 	case SCTP_EVENTS:
5322 		retval = sctp_getsockopt_events(sk, len, optval, optlen);
5323 		break;
5324 	case SCTP_AUTOCLOSE:
5325 		retval = sctp_getsockopt_autoclose(sk, len, optval, optlen);
5326 		break;
5327 	case SCTP_SOCKOPT_PEELOFF:
5328 		retval = sctp_getsockopt_peeloff(sk, len, optval, optlen);
5329 		break;
5330 	case SCTP_PEER_ADDR_PARAMS:
5331 		retval = sctp_getsockopt_peer_addr_params(sk, len, optval,
5332 							  optlen);
5333 		break;
5334 	case SCTP_DELAYED_SACK:
5335 		retval = sctp_getsockopt_delayed_ack(sk, len, optval,
5336 							  optlen);
5337 		break;
5338 	case SCTP_INITMSG:
5339 		retval = sctp_getsockopt_initmsg(sk, len, optval, optlen);
5340 		break;
5341 	case SCTP_GET_PEER_ADDRS:
5342 		retval = sctp_getsockopt_peer_addrs(sk, len, optval,
5343 						    optlen);
5344 		break;
5345 	case SCTP_GET_LOCAL_ADDRS:
5346 		retval = sctp_getsockopt_local_addrs(sk, len, optval,
5347 						     optlen);
5348 		break;
5349 	case SCTP_SOCKOPT_CONNECTX3:
5350 		retval = sctp_getsockopt_connectx3(sk, len, optval, optlen);
5351 		break;
5352 	case SCTP_DEFAULT_SEND_PARAM:
5353 		retval = sctp_getsockopt_default_send_param(sk, len,
5354 							    optval, optlen);
5355 		break;
5356 	case SCTP_PRIMARY_ADDR:
5357 		retval = sctp_getsockopt_primary_addr(sk, len, optval, optlen);
5358 		break;
5359 	case SCTP_NODELAY:
5360 		retval = sctp_getsockopt_nodelay(sk, len, optval, optlen);
5361 		break;
5362 	case SCTP_RTOINFO:
5363 		retval = sctp_getsockopt_rtoinfo(sk, len, optval, optlen);
5364 		break;
5365 	case SCTP_ASSOCINFO:
5366 		retval = sctp_getsockopt_associnfo(sk, len, optval, optlen);
5367 		break;
5368 	case SCTP_I_WANT_MAPPED_V4_ADDR:
5369 		retval = sctp_getsockopt_mappedv4(sk, len, optval, optlen);
5370 		break;
5371 	case SCTP_MAXSEG:
5372 		retval = sctp_getsockopt_maxseg(sk, len, optval, optlen);
5373 		break;
5374 	case SCTP_GET_PEER_ADDR_INFO:
5375 		retval = sctp_getsockopt_peer_addr_info(sk, len, optval,
5376 							optlen);
5377 		break;
5378 	case SCTP_ADAPTATION_LAYER:
5379 		retval = sctp_getsockopt_adaptation_layer(sk, len, optval,
5380 							optlen);
5381 		break;
5382 	case SCTP_CONTEXT:
5383 		retval = sctp_getsockopt_context(sk, len, optval, optlen);
5384 		break;
5385 	case SCTP_FRAGMENT_INTERLEAVE:
5386 		retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
5387 							     optlen);
5388 		break;
5389 	case SCTP_PARTIAL_DELIVERY_POINT:
5390 		retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
5391 								optlen);
5392 		break;
5393 	case SCTP_MAX_BURST:
5394 		retval = sctp_getsockopt_maxburst(sk, len, optval, optlen);
5395 		break;
5396 	case SCTP_AUTH_KEY:
5397 	case SCTP_AUTH_CHUNK:
5398 	case SCTP_AUTH_DELETE_KEY:
5399 		retval = -EOPNOTSUPP;
5400 		break;
5401 	case SCTP_HMAC_IDENT:
5402 		retval = sctp_getsockopt_hmac_ident(sk, len, optval, optlen);
5403 		break;
5404 	case SCTP_AUTH_ACTIVE_KEY:
5405 		retval = sctp_getsockopt_active_key(sk, len, optval, optlen);
5406 		break;
5407 	case SCTP_PEER_AUTH_CHUNKS:
5408 		retval = sctp_getsockopt_peer_auth_chunks(sk, len, optval,
5409 							optlen);
5410 		break;
5411 	case SCTP_LOCAL_AUTH_CHUNKS:
5412 		retval = sctp_getsockopt_local_auth_chunks(sk, len, optval,
5413 							optlen);
5414 		break;
5415 	case SCTP_GET_ASSOC_NUMBER:
5416 		retval = sctp_getsockopt_assoc_number(sk, len, optval, optlen);
5417 		break;
5418 	default:
5419 		retval = -ENOPROTOOPT;
5420 		break;
5421 	}
5422 
5423 	sctp_release_sock(sk);
5424 	return retval;
5425 }
5426 
sctp_hash(struct sock * sk)5427 static void sctp_hash(struct sock *sk)
5428 {
5429 	/* STUB */
5430 }
5431 
sctp_unhash(struct sock * sk)5432 static void sctp_unhash(struct sock *sk)
5433 {
5434 	/* STUB */
5435 }
5436 
5437 /* Check if port is acceptable.  Possibly find first available port.
5438  *
5439  * The port hash table (contained in the 'global' SCTP protocol storage
5440  * returned by struct sctp_protocol *sctp_get_protocol()). The hash
5441  * table is an array of 4096 lists (sctp_bind_hashbucket). Each
5442  * list (the list number is the port number hashed out, so as you
5443  * would expect from a hash function, all the ports in a given list have
5444  * such a number that hashes out to the same list number; you were
5445  * expecting that, right?); so each list has a set of ports, with a
5446  * link to the socket (struct sock) that uses it, the port number and
5447  * a fastreuse flag (FIXME: NPI ipg).
5448  */
5449 static struct sctp_bind_bucket *sctp_bucket_create(
5450 	struct sctp_bind_hashbucket *head, unsigned short snum);
5451 
sctp_get_port_local(struct sock * sk,union sctp_addr * addr)5452 static long sctp_get_port_local(struct sock *sk, union sctp_addr *addr)
5453 {
5454 	struct sctp_bind_hashbucket *head; /* hash list */
5455 	struct sctp_bind_bucket *pp; /* hash list port iterator */
5456 	struct hlist_node *node;
5457 	unsigned short snum;
5458 	int ret;
5459 
5460 	snum = ntohs(addr->v4.sin_port);
5461 
5462 	SCTP_DEBUG_PRINTK("sctp_get_port() begins, snum=%d\n", snum);
5463 	sctp_local_bh_disable();
5464 
5465 	if (snum == 0) {
5466 		/* Search for an available port. */
5467 		int low, high, remaining, index;
5468 		unsigned int rover;
5469 
5470 		inet_get_local_port_range(&low, &high);
5471 		remaining = (high - low) + 1;
5472 		rover = net_random() % remaining + low;
5473 
5474 		do {
5475 			rover++;
5476 			if ((rover < low) || (rover > high))
5477 				rover = low;
5478 			if (inet_is_reserved_local_port(rover))
5479 				continue;
5480 			index = sctp_phashfn(rover);
5481 			head = &sctp_port_hashtable[index];
5482 			sctp_spin_lock(&head->lock);
5483 			sctp_for_each_hentry(pp, node, &head->chain)
5484 				if (pp->port == rover)
5485 					goto next;
5486 			break;
5487 		next:
5488 			sctp_spin_unlock(&head->lock);
5489 		} while (--remaining > 0);
5490 
5491 		/* Exhausted local port range during search? */
5492 		ret = 1;
5493 		if (remaining <= 0)
5494 			goto fail;
5495 
5496 		/* OK, here is the one we will use.  HEAD (the port
5497 		 * hash table list entry) is non-NULL and we hold it's
5498 		 * mutex.
5499 		 */
5500 		snum = rover;
5501 	} else {
5502 		/* We are given an specific port number; we verify
5503 		 * that it is not being used. If it is used, we will
5504 		 * exahust the search in the hash list corresponding
5505 		 * to the port number (snum) - we detect that with the
5506 		 * port iterator, pp being NULL.
5507 		 */
5508 		head = &sctp_port_hashtable[sctp_phashfn(snum)];
5509 		sctp_spin_lock(&head->lock);
5510 		sctp_for_each_hentry(pp, node, &head->chain) {
5511 			if (pp->port == snum)
5512 				goto pp_found;
5513 		}
5514 	}
5515 	pp = NULL;
5516 	goto pp_not_found;
5517 pp_found:
5518 	if (!hlist_empty(&pp->owner)) {
5519 		/* We had a port hash table hit - there is an
5520 		 * available port (pp != NULL) and it is being
5521 		 * used by other socket (pp->owner not empty); that other
5522 		 * socket is going to be sk2.
5523 		 */
5524 		int reuse = sk->sk_reuse;
5525 		struct sock *sk2;
5526 
5527 		SCTP_DEBUG_PRINTK("sctp_get_port() found a possible match\n");
5528 		if (pp->fastreuse && sk->sk_reuse &&
5529 			sk->sk_state != SCTP_SS_LISTENING)
5530 			goto success;
5531 
5532 		/* Run through the list of sockets bound to the port
5533 		 * (pp->port) [via the pointers bind_next and
5534 		 * bind_pprev in the struct sock *sk2 (pp->sk)]. On each one,
5535 		 * we get the endpoint they describe and run through
5536 		 * the endpoint's list of IP (v4 or v6) addresses,
5537 		 * comparing each of the addresses with the address of
5538 		 * the socket sk. If we find a match, then that means
5539 		 * that this port/socket (sk) combination are already
5540 		 * in an endpoint.
5541 		 */
5542 		sk_for_each_bound(sk2, node, &pp->owner) {
5543 			struct sctp_endpoint *ep2;
5544 			ep2 = sctp_sk(sk2)->ep;
5545 
5546 			if (sk == sk2 ||
5547 			    (reuse && sk2->sk_reuse &&
5548 			     sk2->sk_state != SCTP_SS_LISTENING))
5549 				continue;
5550 
5551 			if (sctp_bind_addr_conflict(&ep2->base.bind_addr, addr,
5552 						 sctp_sk(sk2), sctp_sk(sk))) {
5553 				ret = (long)sk2;
5554 				goto fail_unlock;
5555 			}
5556 		}
5557 		SCTP_DEBUG_PRINTK("sctp_get_port(): Found a match\n");
5558 	}
5559 pp_not_found:
5560 	/* If there was a hash table miss, create a new port.  */
5561 	ret = 1;
5562 	if (!pp && !(pp = sctp_bucket_create(head, snum)))
5563 		goto fail_unlock;
5564 
5565 	/* In either case (hit or miss), make sure fastreuse is 1 only
5566 	 * if sk->sk_reuse is too (that is, if the caller requested
5567 	 * SO_REUSEADDR on this socket -sk-).
5568 	 */
5569 	if (hlist_empty(&pp->owner)) {
5570 		if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
5571 			pp->fastreuse = 1;
5572 		else
5573 			pp->fastreuse = 0;
5574 	} else if (pp->fastreuse &&
5575 		(!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
5576 		pp->fastreuse = 0;
5577 
5578 	/* We are set, so fill up all the data in the hash table
5579 	 * entry, tie the socket list information with the rest of the
5580 	 * sockets FIXME: Blurry, NPI (ipg).
5581 	 */
5582 success:
5583 	if (!sctp_sk(sk)->bind_hash) {
5584 		inet_sk(sk)->inet_num = snum;
5585 		sk_add_bind_node(sk, &pp->owner);
5586 		sctp_sk(sk)->bind_hash = pp;
5587 	}
5588 	ret = 0;
5589 
5590 fail_unlock:
5591 	sctp_spin_unlock(&head->lock);
5592 
5593 fail:
5594 	sctp_local_bh_enable();
5595 	return ret;
5596 }
5597 
5598 /* Assign a 'snum' port to the socket.  If snum == 0, an ephemeral
5599  * port is requested.
5600  */
sctp_get_port(struct sock * sk,unsigned short snum)5601 static int sctp_get_port(struct sock *sk, unsigned short snum)
5602 {
5603 	long ret;
5604 	union sctp_addr addr;
5605 	struct sctp_af *af = sctp_sk(sk)->pf->af;
5606 
5607 	/* Set up a dummy address struct from the sk. */
5608 	af->from_sk(&addr, sk);
5609 	addr.v4.sin_port = htons(snum);
5610 
5611 	/* Note: sk->sk_num gets filled in if ephemeral port request. */
5612 	ret = sctp_get_port_local(sk, &addr);
5613 
5614 	return ret ? 1 : 0;
5615 }
5616 
5617 /*
5618  *  Move a socket to LISTENING state.
5619  */
sctp_listen_start(struct sock * sk,int backlog)5620 SCTP_STATIC int sctp_listen_start(struct sock *sk, int backlog)
5621 {
5622 	struct sctp_sock *sp = sctp_sk(sk);
5623 	struct sctp_endpoint *ep = sp->ep;
5624 	struct crypto_hash *tfm = NULL;
5625 
5626 	/* Allocate HMAC for generating cookie. */
5627 	if (!sctp_sk(sk)->hmac && sctp_hmac_alg) {
5628 		tfm = crypto_alloc_hash(sctp_hmac_alg, 0, CRYPTO_ALG_ASYNC);
5629 		if (IS_ERR(tfm)) {
5630 			if (net_ratelimit()) {
5631 				pr_info("failed to load transform for %s: %ld\n",
5632 					sctp_hmac_alg, PTR_ERR(tfm));
5633 			}
5634 			return -ENOSYS;
5635 		}
5636 		sctp_sk(sk)->hmac = tfm;
5637 	}
5638 
5639 	/*
5640 	 * If a bind() or sctp_bindx() is not called prior to a listen()
5641 	 * call that allows new associations to be accepted, the system
5642 	 * picks an ephemeral port and will choose an address set equivalent
5643 	 * to binding with a wildcard address.
5644 	 *
5645 	 * This is not currently spelled out in the SCTP sockets
5646 	 * extensions draft, but follows the practice as seen in TCP
5647 	 * sockets.
5648 	 *
5649 	 */
5650 	sk->sk_state = SCTP_SS_LISTENING;
5651 	if (!ep->base.bind_addr.port) {
5652 		if (sctp_autobind(sk))
5653 			return -EAGAIN;
5654 	} else {
5655 		if (sctp_get_port(sk, inet_sk(sk)->inet_num)) {
5656 			sk->sk_state = SCTP_SS_CLOSED;
5657 			return -EADDRINUSE;
5658 		}
5659 	}
5660 
5661 	sk->sk_max_ack_backlog = backlog;
5662 	sctp_hash_endpoint(ep);
5663 	return 0;
5664 }
5665 
5666 /*
5667  * 4.1.3 / 5.1.3 listen()
5668  *
5669  *   By default, new associations are not accepted for UDP style sockets.
5670  *   An application uses listen() to mark a socket as being able to
5671  *   accept new associations.
5672  *
5673  *   On TCP style sockets, applications use listen() to ready the SCTP
5674  *   endpoint for accepting inbound associations.
5675  *
5676  *   On both types of endpoints a backlog of '0' disables listening.
5677  *
5678  *  Move a socket to LISTENING state.
5679  */
sctp_inet_listen(struct socket * sock,int backlog)5680 int sctp_inet_listen(struct socket *sock, int backlog)
5681 {
5682 	struct sock *sk = sock->sk;
5683 	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
5684 	int err = -EINVAL;
5685 
5686 	if (unlikely(backlog < 0))
5687 		return err;
5688 
5689 	sctp_lock_sock(sk);
5690 
5691 	/* Peeled-off sockets are not allowed to listen().  */
5692 	if (sctp_style(sk, UDP_HIGH_BANDWIDTH))
5693 		goto out;
5694 
5695 	if (sock->state != SS_UNCONNECTED)
5696 		goto out;
5697 
5698 	/* If backlog is zero, disable listening. */
5699 	if (!backlog) {
5700 		if (sctp_sstate(sk, CLOSED))
5701 			goto out;
5702 
5703 		err = 0;
5704 		sctp_unhash_endpoint(ep);
5705 		sk->sk_state = SCTP_SS_CLOSED;
5706 		if (sk->sk_reuse)
5707 			sctp_sk(sk)->bind_hash->fastreuse = 1;
5708 		goto out;
5709 	}
5710 
5711 	/* If we are already listening, just update the backlog */
5712 	if (sctp_sstate(sk, LISTENING))
5713 		sk->sk_max_ack_backlog = backlog;
5714 	else {
5715 		err = sctp_listen_start(sk, backlog);
5716 		if (err)
5717 			goto out;
5718 	}
5719 
5720 	err = 0;
5721 out:
5722 	sctp_release_sock(sk);
5723 	return err;
5724 }
5725 
5726 /*
5727  * This function is done by modeling the current datagram_poll() and the
5728  * tcp_poll().  Note that, based on these implementations, we don't
5729  * lock the socket in this function, even though it seems that,
5730  * ideally, locking or some other mechanisms can be used to ensure
5731  * the integrity of the counters (sndbuf and wmem_alloc) used
5732  * in this place.  We assume that we don't need locks either until proven
5733  * otherwise.
5734  *
5735  * Another thing to note is that we include the Async I/O support
5736  * here, again, by modeling the current TCP/UDP code.  We don't have
5737  * a good way to test with it yet.
5738  */
sctp_poll(struct file * file,struct socket * sock,poll_table * wait)5739 unsigned int sctp_poll(struct file *file, struct socket *sock, poll_table *wait)
5740 {
5741 	struct sock *sk = sock->sk;
5742 	struct sctp_sock *sp = sctp_sk(sk);
5743 	unsigned int mask;
5744 
5745 	poll_wait(file, sk_sleep(sk), wait);
5746 
5747 	/* A TCP-style listening socket becomes readable when the accept queue
5748 	 * is not empty.
5749 	 */
5750 	if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
5751 		return (!list_empty(&sp->ep->asocs)) ?
5752 			(POLLIN | POLLRDNORM) : 0;
5753 
5754 	mask = 0;
5755 
5756 	/* Is there any exceptional events?  */
5757 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
5758 		mask |= POLLERR;
5759 	if (sk->sk_shutdown & RCV_SHUTDOWN)
5760 		mask |= POLLRDHUP | POLLIN | POLLRDNORM;
5761 	if (sk->sk_shutdown == SHUTDOWN_MASK)
5762 		mask |= POLLHUP;
5763 
5764 	/* Is it readable?  Reconsider this code with TCP-style support.  */
5765 	if (!skb_queue_empty(&sk->sk_receive_queue))
5766 		mask |= POLLIN | POLLRDNORM;
5767 
5768 	/* The association is either gone or not ready.  */
5769 	if (!sctp_style(sk, UDP) && sctp_sstate(sk, CLOSED))
5770 		return mask;
5771 
5772 	/* Is it writable?  */
5773 	if (sctp_writeable(sk)) {
5774 		mask |= POLLOUT | POLLWRNORM;
5775 	} else {
5776 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
5777 		/*
5778 		 * Since the socket is not locked, the buffer
5779 		 * might be made available after the writeable check and
5780 		 * before the bit is set.  This could cause a lost I/O
5781 		 * signal.  tcp_poll() has a race breaker for this race
5782 		 * condition.  Based on their implementation, we put
5783 		 * in the following code to cover it as well.
5784 		 */
5785 		if (sctp_writeable(sk))
5786 			mask |= POLLOUT | POLLWRNORM;
5787 	}
5788 	return mask;
5789 }
5790 
5791 /********************************************************************
5792  * 2nd Level Abstractions
5793  ********************************************************************/
5794 
sctp_bucket_create(struct sctp_bind_hashbucket * head,unsigned short snum)5795 static struct sctp_bind_bucket *sctp_bucket_create(
5796 	struct sctp_bind_hashbucket *head, unsigned short snum)
5797 {
5798 	struct sctp_bind_bucket *pp;
5799 
5800 	pp = kmem_cache_alloc(sctp_bucket_cachep, GFP_ATOMIC);
5801 	if (pp) {
5802 		SCTP_DBG_OBJCNT_INC(bind_bucket);
5803 		pp->port = snum;
5804 		pp->fastreuse = 0;
5805 		INIT_HLIST_HEAD(&pp->owner);
5806 		hlist_add_head(&pp->node, &head->chain);
5807 	}
5808 	return pp;
5809 }
5810 
5811 /* Caller must hold hashbucket lock for this tb with local BH disabled */
sctp_bucket_destroy(struct sctp_bind_bucket * pp)5812 static void sctp_bucket_destroy(struct sctp_bind_bucket *pp)
5813 {
5814 	if (pp && hlist_empty(&pp->owner)) {
5815 		__hlist_del(&pp->node);
5816 		kmem_cache_free(sctp_bucket_cachep, pp);
5817 		SCTP_DBG_OBJCNT_DEC(bind_bucket);
5818 	}
5819 }
5820 
5821 /* Release this socket's reference to a local port.  */
__sctp_put_port(struct sock * sk)5822 static inline void __sctp_put_port(struct sock *sk)
5823 {
5824 	struct sctp_bind_hashbucket *head =
5825 		&sctp_port_hashtable[sctp_phashfn(inet_sk(sk)->inet_num)];
5826 	struct sctp_bind_bucket *pp;
5827 
5828 	sctp_spin_lock(&head->lock);
5829 	pp = sctp_sk(sk)->bind_hash;
5830 	__sk_del_bind_node(sk);
5831 	sctp_sk(sk)->bind_hash = NULL;
5832 	inet_sk(sk)->inet_num = 0;
5833 	sctp_bucket_destroy(pp);
5834 	sctp_spin_unlock(&head->lock);
5835 }
5836 
sctp_put_port(struct sock * sk)5837 void sctp_put_port(struct sock *sk)
5838 {
5839 	sctp_local_bh_disable();
5840 	__sctp_put_port(sk);
5841 	sctp_local_bh_enable();
5842 }
5843 
5844 /*
5845  * The system picks an ephemeral port and choose an address set equivalent
5846  * to binding with a wildcard address.
5847  * One of those addresses will be the primary address for the association.
5848  * This automatically enables the multihoming capability of SCTP.
5849  */
sctp_autobind(struct sock * sk)5850 static int sctp_autobind(struct sock *sk)
5851 {
5852 	union sctp_addr autoaddr;
5853 	struct sctp_af *af;
5854 	__be16 port;
5855 
5856 	/* Initialize a local sockaddr structure to INADDR_ANY. */
5857 	af = sctp_sk(sk)->pf->af;
5858 
5859 	port = htons(inet_sk(sk)->inet_num);
5860 	af->inaddr_any(&autoaddr, port);
5861 
5862 	return sctp_do_bind(sk, &autoaddr, af->sockaddr_len);
5863 }
5864 
5865 /* Parse out IPPROTO_SCTP CMSG headers.  Perform only minimal validation.
5866  *
5867  * From RFC 2292
5868  * 4.2 The cmsghdr Structure *
5869  *
5870  * When ancillary data is sent or received, any number of ancillary data
5871  * objects can be specified by the msg_control and msg_controllen members of
5872  * the msghdr structure, because each object is preceded by
5873  * a cmsghdr structure defining the object's length (the cmsg_len member).
5874  * Historically Berkeley-derived implementations have passed only one object
5875  * at a time, but this API allows multiple objects to be
5876  * passed in a single call to sendmsg() or recvmsg(). The following example
5877  * shows two ancillary data objects in a control buffer.
5878  *
5879  *   |<--------------------------- msg_controllen -------------------------->|
5880  *   |                                                                       |
5881  *
5882  *   |<----- ancillary data object ----->|<----- ancillary data object ----->|
5883  *
5884  *   |<---------- CMSG_SPACE() --------->|<---------- CMSG_SPACE() --------->|
5885  *   |                                   |                                   |
5886  *
5887  *   |<---------- cmsg_len ---------->|  |<--------- cmsg_len ----------->|  |
5888  *
5889  *   |<--------- CMSG_LEN() --------->|  |<-------- CMSG_LEN() ---------->|  |
5890  *   |                                |  |                                |  |
5891  *
5892  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5893  *   |cmsg_|cmsg_|cmsg_|XX|           |XX|cmsg_|cmsg_|cmsg_|XX|           |XX|
5894  *
5895  *   |len  |level|type |XX|cmsg_data[]|XX|len  |level|type |XX|cmsg_data[]|XX|
5896  *
5897  *   +-----+-----+-----+--+-----------+--+-----+-----+-----+--+-----------+--+
5898  *    ^
5899  *    |
5900  *
5901  * msg_control
5902  * points here
5903  */
sctp_msghdr_parse(const struct msghdr * msg,sctp_cmsgs_t * cmsgs)5904 SCTP_STATIC int sctp_msghdr_parse(const struct msghdr *msg,
5905 				  sctp_cmsgs_t *cmsgs)
5906 {
5907 	struct cmsghdr *cmsg;
5908 	struct msghdr *my_msg = (struct msghdr *)msg;
5909 
5910 	for (cmsg = CMSG_FIRSTHDR(msg);
5911 	     cmsg != NULL;
5912 	     cmsg = CMSG_NXTHDR(my_msg, cmsg)) {
5913 		if (!CMSG_OK(my_msg, cmsg))
5914 			return -EINVAL;
5915 
5916 		/* Should we parse this header or ignore?  */
5917 		if (cmsg->cmsg_level != IPPROTO_SCTP)
5918 			continue;
5919 
5920 		/* Strictly check lengths following example in SCM code.  */
5921 		switch (cmsg->cmsg_type) {
5922 		case SCTP_INIT:
5923 			/* SCTP Socket API Extension
5924 			 * 5.2.1 SCTP Initiation Structure (SCTP_INIT)
5925 			 *
5926 			 * This cmsghdr structure provides information for
5927 			 * initializing new SCTP associations with sendmsg().
5928 			 * The SCTP_INITMSG socket option uses this same data
5929 			 * structure.  This structure is not used for
5930 			 * recvmsg().
5931 			 *
5932 			 * cmsg_level    cmsg_type      cmsg_data[]
5933 			 * ------------  ------------   ----------------------
5934 			 * IPPROTO_SCTP  SCTP_INIT      struct sctp_initmsg
5935 			 */
5936 			if (cmsg->cmsg_len !=
5937 			    CMSG_LEN(sizeof(struct sctp_initmsg)))
5938 				return -EINVAL;
5939 			cmsgs->init = (struct sctp_initmsg *)CMSG_DATA(cmsg);
5940 			break;
5941 
5942 		case SCTP_SNDRCV:
5943 			/* SCTP Socket API Extension
5944 			 * 5.2.2 SCTP Header Information Structure(SCTP_SNDRCV)
5945 			 *
5946 			 * This cmsghdr structure specifies SCTP options for
5947 			 * sendmsg() and describes SCTP header information
5948 			 * about a received message through recvmsg().
5949 			 *
5950 			 * cmsg_level    cmsg_type      cmsg_data[]
5951 			 * ------------  ------------   ----------------------
5952 			 * IPPROTO_SCTP  SCTP_SNDRCV    struct sctp_sndrcvinfo
5953 			 */
5954 			if (cmsg->cmsg_len !=
5955 			    CMSG_LEN(sizeof(struct sctp_sndrcvinfo)))
5956 				return -EINVAL;
5957 
5958 			cmsgs->info =
5959 				(struct sctp_sndrcvinfo *)CMSG_DATA(cmsg);
5960 
5961 			/* Minimally, validate the sinfo_flags. */
5962 			if (cmsgs->info->sinfo_flags &
5963 			    ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
5964 			      SCTP_ABORT | SCTP_EOF))
5965 				return -EINVAL;
5966 			break;
5967 
5968 		default:
5969 			return -EINVAL;
5970 		}
5971 	}
5972 	return 0;
5973 }
5974 
5975 /*
5976  * Wait for a packet..
5977  * Note: This function is the same function as in core/datagram.c
5978  * with a few modifications to make lksctp work.
5979  */
sctp_wait_for_packet(struct sock * sk,int * err,long * timeo_p)5980 static int sctp_wait_for_packet(struct sock * sk, int *err, long *timeo_p)
5981 {
5982 	int error;
5983 	DEFINE_WAIT(wait);
5984 
5985 	prepare_to_wait_exclusive(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
5986 
5987 	/* Socket errors? */
5988 	error = sock_error(sk);
5989 	if (error)
5990 		goto out;
5991 
5992 	if (!skb_queue_empty(&sk->sk_receive_queue))
5993 		goto ready;
5994 
5995 	/* Socket shut down?  */
5996 	if (sk->sk_shutdown & RCV_SHUTDOWN)
5997 		goto out;
5998 
5999 	/* Sequenced packets can come disconnected.  If so we report the
6000 	 * problem.
6001 	 */
6002 	error = -ENOTCONN;
6003 
6004 	/* Is there a good reason to think that we may receive some data?  */
6005 	if (list_empty(&sctp_sk(sk)->ep->asocs) && !sctp_sstate(sk, LISTENING))
6006 		goto out;
6007 
6008 	/* Handle signals.  */
6009 	if (signal_pending(current))
6010 		goto interrupted;
6011 
6012 	/* Let another process have a go.  Since we are going to sleep
6013 	 * anyway.  Note: This may cause odd behaviors if the message
6014 	 * does not fit in the user's buffer, but this seems to be the
6015 	 * only way to honor MSG_DONTWAIT realistically.
6016 	 */
6017 	sctp_release_sock(sk);
6018 	*timeo_p = schedule_timeout(*timeo_p);
6019 	sctp_lock_sock(sk);
6020 
6021 ready:
6022 	finish_wait(sk_sleep(sk), &wait);
6023 	return 0;
6024 
6025 interrupted:
6026 	error = sock_intr_errno(*timeo_p);
6027 
6028 out:
6029 	finish_wait(sk_sleep(sk), &wait);
6030 	*err = error;
6031 	return error;
6032 }
6033 
6034 /* Receive a datagram.
6035  * Note: This is pretty much the same routine as in core/datagram.c
6036  * with a few changes to make lksctp work.
6037  */
sctp_skb_recv_datagram(struct sock * sk,int flags,int noblock,int * err)6038 static struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
6039 					      int noblock, int *err)
6040 {
6041 	int error;
6042 	struct sk_buff *skb;
6043 	long timeo;
6044 
6045 	timeo = sock_rcvtimeo(sk, noblock);
6046 
6047 	SCTP_DEBUG_PRINTK("Timeout: timeo: %ld, MAX: %ld.\n",
6048 			  timeo, MAX_SCHEDULE_TIMEOUT);
6049 
6050 	do {
6051 		/* Again only user level code calls this function,
6052 		 * so nothing interrupt level
6053 		 * will suddenly eat the receive_queue.
6054 		 *
6055 		 *  Look at current nfs client by the way...
6056 		 *  However, this function was correct in any case. 8)
6057 		 */
6058 		if (flags & MSG_PEEK) {
6059 			spin_lock_bh(&sk->sk_receive_queue.lock);
6060 			skb = skb_peek(&sk->sk_receive_queue);
6061 			if (skb)
6062 				atomic_inc(&skb->users);
6063 			spin_unlock_bh(&sk->sk_receive_queue.lock);
6064 		} else {
6065 			skb = skb_dequeue(&sk->sk_receive_queue);
6066 		}
6067 
6068 		if (skb)
6069 			return skb;
6070 
6071 		/* Caller is allowed not to check sk->sk_err before calling. */
6072 		error = sock_error(sk);
6073 		if (error)
6074 			goto no_packet;
6075 
6076 		if (sk->sk_shutdown & RCV_SHUTDOWN)
6077 			break;
6078 
6079 		/* User doesn't want to wait.  */
6080 		error = -EAGAIN;
6081 		if (!timeo)
6082 			goto no_packet;
6083 	} while (sctp_wait_for_packet(sk, err, &timeo) == 0);
6084 
6085 	return NULL;
6086 
6087 no_packet:
6088 	*err = error;
6089 	return NULL;
6090 }
6091 
6092 /* If sndbuf has changed, wake up per association sndbuf waiters.  */
__sctp_write_space(struct sctp_association * asoc)6093 static void __sctp_write_space(struct sctp_association *asoc)
6094 {
6095 	struct sock *sk = asoc->base.sk;
6096 	struct socket *sock = sk->sk_socket;
6097 
6098 	if ((sctp_wspace(asoc) > 0) && sock) {
6099 		if (waitqueue_active(&asoc->wait))
6100 			wake_up_interruptible(&asoc->wait);
6101 
6102 		if (sctp_writeable(sk)) {
6103 			wait_queue_head_t *wq = sk_sleep(sk);
6104 
6105 			if (wq && waitqueue_active(wq))
6106 				wake_up_interruptible(wq);
6107 
6108 			/* Note that we try to include the Async I/O support
6109 			 * here by modeling from the current TCP/UDP code.
6110 			 * We have not tested with it yet.
6111 			 */
6112 			if (!(sk->sk_shutdown & SEND_SHUTDOWN))
6113 				sock_wake_async(sock,
6114 						SOCK_WAKE_SPACE, POLL_OUT);
6115 		}
6116 	}
6117 }
6118 
6119 /* Do accounting for the sndbuf space.
6120  * Decrement the used sndbuf space of the corresponding association by the
6121  * data size which was just transmitted(freed).
6122  */
sctp_wfree(struct sk_buff * skb)6123 static void sctp_wfree(struct sk_buff *skb)
6124 {
6125 	struct sctp_association *asoc;
6126 	struct sctp_chunk *chunk;
6127 	struct sock *sk;
6128 
6129 	/* Get the saved chunk pointer.  */
6130 	chunk = *((struct sctp_chunk **)(skb->cb));
6131 	asoc = chunk->asoc;
6132 	sk = asoc->base.sk;
6133 	asoc->sndbuf_used -= SCTP_DATA_SNDSIZE(chunk) +
6134 				sizeof(struct sk_buff) +
6135 				sizeof(struct sctp_chunk);
6136 
6137 	atomic_sub(sizeof(struct sctp_chunk), &sk->sk_wmem_alloc);
6138 
6139 	/*
6140 	 * This undoes what is done via sctp_set_owner_w and sk_mem_charge
6141 	 */
6142 	sk->sk_wmem_queued   -= skb->truesize;
6143 	sk_mem_uncharge(sk, skb->truesize);
6144 
6145 	sock_wfree(skb);
6146 	__sctp_write_space(asoc);
6147 
6148 	sctp_association_put(asoc);
6149 }
6150 
6151 /* Do accounting for the receive space on the socket.
6152  * Accounting for the association is done in ulpevent.c
6153  * We set this as a destructor for the cloned data skbs so that
6154  * accounting is done at the correct time.
6155  */
sctp_sock_rfree(struct sk_buff * skb)6156 void sctp_sock_rfree(struct sk_buff *skb)
6157 {
6158 	struct sock *sk = skb->sk;
6159 	struct sctp_ulpevent *event = sctp_skb2event(skb);
6160 
6161 	atomic_sub(event->rmem_len, &sk->sk_rmem_alloc);
6162 
6163 	/*
6164 	 * Mimic the behavior of sock_rfree
6165 	 */
6166 	sk_mem_uncharge(sk, event->rmem_len);
6167 }
6168 
6169 
6170 /* Helper function to wait for space in the sndbuf.  */
sctp_wait_for_sndbuf(struct sctp_association * asoc,long * timeo_p,size_t msg_len)6171 static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
6172 				size_t msg_len)
6173 {
6174 	struct sock *sk = asoc->base.sk;
6175 	int err = 0;
6176 	long current_timeo = *timeo_p;
6177 	DEFINE_WAIT(wait);
6178 
6179 	SCTP_DEBUG_PRINTK("wait_for_sndbuf: asoc=%p, timeo=%ld, msg_len=%zu\n",
6180 			  asoc, (long)(*timeo_p), msg_len);
6181 
6182 	/* Increment the association's refcnt.  */
6183 	sctp_association_hold(asoc);
6184 
6185 	/* Wait on the association specific sndbuf space. */
6186 	for (;;) {
6187 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6188 					  TASK_INTERRUPTIBLE);
6189 		if (!*timeo_p)
6190 			goto do_nonblock;
6191 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6192 		    asoc->base.dead)
6193 			goto do_error;
6194 		if (signal_pending(current))
6195 			goto do_interrupted;
6196 		if (msg_len <= sctp_wspace(asoc))
6197 			break;
6198 
6199 		/* Let another process have a go.  Since we are going
6200 		 * to sleep anyway.
6201 		 */
6202 		sctp_release_sock(sk);
6203 		current_timeo = schedule_timeout(current_timeo);
6204 		BUG_ON(sk != asoc->base.sk);
6205 		sctp_lock_sock(sk);
6206 
6207 		*timeo_p = current_timeo;
6208 	}
6209 
6210 out:
6211 	finish_wait(&asoc->wait, &wait);
6212 
6213 	/* Release the association's refcnt.  */
6214 	sctp_association_put(asoc);
6215 
6216 	return err;
6217 
6218 do_error:
6219 	err = -EPIPE;
6220 	goto out;
6221 
6222 do_interrupted:
6223 	err = sock_intr_errno(*timeo_p);
6224 	goto out;
6225 
6226 do_nonblock:
6227 	err = -EAGAIN;
6228 	goto out;
6229 }
6230 
sctp_data_ready(struct sock * sk,int len)6231 void sctp_data_ready(struct sock *sk, int len)
6232 {
6233 	struct socket_wq *wq;
6234 
6235 	rcu_read_lock();
6236 	wq = rcu_dereference(sk->sk_wq);
6237 	if (wq_has_sleeper(wq))
6238 		wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
6239 						POLLRDNORM | POLLRDBAND);
6240 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
6241 	rcu_read_unlock();
6242 }
6243 
6244 /* If socket sndbuf has changed, wake up all per association waiters.  */
sctp_write_space(struct sock * sk)6245 void sctp_write_space(struct sock *sk)
6246 {
6247 	struct sctp_association *asoc;
6248 
6249 	/* Wake up the tasks in each wait queue.  */
6250 	list_for_each_entry(asoc, &((sctp_sk(sk))->ep->asocs), asocs) {
6251 		__sctp_write_space(asoc);
6252 	}
6253 }
6254 
6255 /* Is there any sndbuf space available on the socket?
6256  *
6257  * Note that sk_wmem_alloc is the sum of the send buffers on all of the
6258  * associations on the same socket.  For a UDP-style socket with
6259  * multiple associations, it is possible for it to be "unwriteable"
6260  * prematurely.  I assume that this is acceptable because
6261  * a premature "unwriteable" is better than an accidental "writeable" which
6262  * would cause an unwanted block under certain circumstances.  For the 1-1
6263  * UDP-style sockets or TCP-style sockets, this code should work.
6264  *  - Daisy
6265  */
sctp_writeable(struct sock * sk)6266 static int sctp_writeable(struct sock *sk)
6267 {
6268 	int amt = 0;
6269 
6270 	amt = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
6271 	if (amt < 0)
6272 		amt = 0;
6273 	return amt;
6274 }
6275 
6276 /* Wait for an association to go into ESTABLISHED state. If timeout is 0,
6277  * returns immediately with EINPROGRESS.
6278  */
sctp_wait_for_connect(struct sctp_association * asoc,long * timeo_p)6279 static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
6280 {
6281 	struct sock *sk = asoc->base.sk;
6282 	int err = 0;
6283 	long current_timeo = *timeo_p;
6284 	DEFINE_WAIT(wait);
6285 
6286 	SCTP_DEBUG_PRINTK("%s: asoc=%p, timeo=%ld\n", __func__, asoc,
6287 			  (long)(*timeo_p));
6288 
6289 	/* Increment the association's refcnt.  */
6290 	sctp_association_hold(asoc);
6291 
6292 	for (;;) {
6293 		prepare_to_wait_exclusive(&asoc->wait, &wait,
6294 					  TASK_INTERRUPTIBLE);
6295 		if (!*timeo_p)
6296 			goto do_nonblock;
6297 		if (sk->sk_shutdown & RCV_SHUTDOWN)
6298 			break;
6299 		if (sk->sk_err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
6300 		    asoc->base.dead)
6301 			goto do_error;
6302 		if (signal_pending(current))
6303 			goto do_interrupted;
6304 
6305 		if (sctp_state(asoc, ESTABLISHED))
6306 			break;
6307 
6308 		/* Let another process have a go.  Since we are going
6309 		 * to sleep anyway.
6310 		 */
6311 		sctp_release_sock(sk);
6312 		current_timeo = schedule_timeout(current_timeo);
6313 		sctp_lock_sock(sk);
6314 
6315 		*timeo_p = current_timeo;
6316 	}
6317 
6318 out:
6319 	finish_wait(&asoc->wait, &wait);
6320 
6321 	/* Release the association's refcnt.  */
6322 	sctp_association_put(asoc);
6323 
6324 	return err;
6325 
6326 do_error:
6327 	if (asoc->init_err_counter + 1 > asoc->max_init_attempts)
6328 		err = -ETIMEDOUT;
6329 	else
6330 		err = -ECONNREFUSED;
6331 	goto out;
6332 
6333 do_interrupted:
6334 	err = sock_intr_errno(*timeo_p);
6335 	goto out;
6336 
6337 do_nonblock:
6338 	err = -EINPROGRESS;
6339 	goto out;
6340 }
6341 
sctp_wait_for_accept(struct sock * sk,long timeo)6342 static int sctp_wait_for_accept(struct sock *sk, long timeo)
6343 {
6344 	struct sctp_endpoint *ep;
6345 	int err = 0;
6346 	DEFINE_WAIT(wait);
6347 
6348 	ep = sctp_sk(sk)->ep;
6349 
6350 
6351 	for (;;) {
6352 		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
6353 					  TASK_INTERRUPTIBLE);
6354 
6355 		if (list_empty(&ep->asocs)) {
6356 			sctp_release_sock(sk);
6357 			timeo = schedule_timeout(timeo);
6358 			sctp_lock_sock(sk);
6359 		}
6360 
6361 		err = -EINVAL;
6362 		if (!sctp_sstate(sk, LISTENING))
6363 			break;
6364 
6365 		err = 0;
6366 		if (!list_empty(&ep->asocs))
6367 			break;
6368 
6369 		err = sock_intr_errno(timeo);
6370 		if (signal_pending(current))
6371 			break;
6372 
6373 		err = -EAGAIN;
6374 		if (!timeo)
6375 			break;
6376 	}
6377 
6378 	finish_wait(sk_sleep(sk), &wait);
6379 
6380 	return err;
6381 }
6382 
sctp_wait_for_close(struct sock * sk,long timeout)6383 static void sctp_wait_for_close(struct sock *sk, long timeout)
6384 {
6385 	DEFINE_WAIT(wait);
6386 
6387 	do {
6388 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
6389 		if (list_empty(&sctp_sk(sk)->ep->asocs))
6390 			break;
6391 		sctp_release_sock(sk);
6392 		timeout = schedule_timeout(timeout);
6393 		sctp_lock_sock(sk);
6394 	} while (!signal_pending(current) && timeout);
6395 
6396 	finish_wait(sk_sleep(sk), &wait);
6397 }
6398 
sctp_skb_set_owner_r_frag(struct sk_buff * skb,struct sock * sk)6399 static void sctp_skb_set_owner_r_frag(struct sk_buff *skb, struct sock *sk)
6400 {
6401 	struct sk_buff *frag;
6402 
6403 	if (!skb->data_len)
6404 		goto done;
6405 
6406 	/* Don't forget the fragments. */
6407 	skb_walk_frags(skb, frag)
6408 		sctp_skb_set_owner_r_frag(frag, sk);
6409 
6410 done:
6411 	sctp_skb_set_owner_r(skb, sk);
6412 }
6413 
sctp_copy_sock(struct sock * newsk,struct sock * sk,struct sctp_association * asoc)6414 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
6415 		    struct sctp_association *asoc)
6416 {
6417 	struct inet_sock *inet = inet_sk(sk);
6418 	struct inet_sock *newinet;
6419 
6420 	newsk->sk_type = sk->sk_type;
6421 	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
6422 	newsk->sk_flags = sk->sk_flags;
6423 	newsk->sk_no_check = sk->sk_no_check;
6424 	newsk->sk_reuse = sk->sk_reuse;
6425 
6426 	newsk->sk_shutdown = sk->sk_shutdown;
6427 	newsk->sk_destruct = inet_sock_destruct;
6428 	newsk->sk_family = sk->sk_family;
6429 	newsk->sk_protocol = IPPROTO_SCTP;
6430 	newsk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
6431 	newsk->sk_sndbuf = sk->sk_sndbuf;
6432 	newsk->sk_rcvbuf = sk->sk_rcvbuf;
6433 	newsk->sk_lingertime = sk->sk_lingertime;
6434 	newsk->sk_rcvtimeo = sk->sk_rcvtimeo;
6435 	newsk->sk_sndtimeo = sk->sk_sndtimeo;
6436 
6437 	newinet = inet_sk(newsk);
6438 
6439 	/* Initialize sk's sport, dport, rcv_saddr and daddr for
6440 	 * getsockname() and getpeername()
6441 	 */
6442 	newinet->inet_sport = inet->inet_sport;
6443 	newinet->inet_saddr = inet->inet_saddr;
6444 	newinet->inet_rcv_saddr = inet->inet_rcv_saddr;
6445 	newinet->inet_dport = htons(asoc->peer.port);
6446 	newinet->pmtudisc = inet->pmtudisc;
6447 	newinet->inet_id = asoc->next_tsn ^ jiffies;
6448 
6449 	newinet->uc_ttl = inet->uc_ttl;
6450 	newinet->mc_loop = 1;
6451 	newinet->mc_ttl = 1;
6452 	newinet->mc_index = 0;
6453 	newinet->mc_list = NULL;
6454 }
6455 
6456 /* Populate the fields of the newsk from the oldsk and migrate the assoc
6457  * and its messages to the newsk.
6458  */
sctp_sock_migrate(struct sock * oldsk,struct sock * newsk,struct sctp_association * assoc,sctp_socket_type_t type)6459 static void sctp_sock_migrate(struct sock *oldsk, struct sock *newsk,
6460 			      struct sctp_association *assoc,
6461 			      sctp_socket_type_t type)
6462 {
6463 	struct sctp_sock *oldsp = sctp_sk(oldsk);
6464 	struct sctp_sock *newsp = sctp_sk(newsk);
6465 	struct sctp_bind_bucket *pp; /* hash list port iterator */
6466 	struct sctp_endpoint *newep = newsp->ep;
6467 	struct sk_buff *skb, *tmp;
6468 	struct sctp_ulpevent *event;
6469 	struct sctp_bind_hashbucket *head;
6470 
6471 	/* Migrate socket buffer sizes and all the socket level options to the
6472 	 * new socket.
6473 	 */
6474 	newsk->sk_sndbuf = oldsk->sk_sndbuf;
6475 	newsk->sk_rcvbuf = oldsk->sk_rcvbuf;
6476 	/* Brute force copy old sctp opt. */
6477 	inet_sk_copy_descendant(newsk, oldsk);
6478 
6479 	/* Restore the ep value that was overwritten with the above structure
6480 	 * copy.
6481 	 */
6482 	newsp->ep = newep;
6483 	newsp->hmac = NULL;
6484 
6485 	/* Hook this new socket in to the bind_hash list. */
6486 	head = &sctp_port_hashtable[sctp_phashfn(inet_sk(oldsk)->inet_num)];
6487 	sctp_local_bh_disable();
6488 	sctp_spin_lock(&head->lock);
6489 	pp = sctp_sk(oldsk)->bind_hash;
6490 	sk_add_bind_node(newsk, &pp->owner);
6491 	sctp_sk(newsk)->bind_hash = pp;
6492 	inet_sk(newsk)->inet_num = inet_sk(oldsk)->inet_num;
6493 	sctp_spin_unlock(&head->lock);
6494 	sctp_local_bh_enable();
6495 
6496 	/* Copy the bind_addr list from the original endpoint to the new
6497 	 * endpoint so that we can handle restarts properly
6498 	 */
6499 	sctp_bind_addr_dup(&newsp->ep->base.bind_addr,
6500 				&oldsp->ep->base.bind_addr, GFP_KERNEL);
6501 
6502 	/* Move any messages in the old socket's receive queue that are for the
6503 	 * peeled off association to the new socket's receive queue.
6504 	 */
6505 	sctp_skb_for_each(skb, &oldsk->sk_receive_queue, tmp) {
6506 		event = sctp_skb2event(skb);
6507 		if (event->asoc == assoc) {
6508 			__skb_unlink(skb, &oldsk->sk_receive_queue);
6509 			__skb_queue_tail(&newsk->sk_receive_queue, skb);
6510 			sctp_skb_set_owner_r_frag(skb, newsk);
6511 		}
6512 	}
6513 
6514 	/* Clean up any messages pending delivery due to partial
6515 	 * delivery.   Three cases:
6516 	 * 1) No partial deliver;  no work.
6517 	 * 2) Peeling off partial delivery; keep pd_lobby in new pd_lobby.
6518 	 * 3) Peeling off non-partial delivery; move pd_lobby to receive_queue.
6519 	 */
6520 	skb_queue_head_init(&newsp->pd_lobby);
6521 	atomic_set(&sctp_sk(newsk)->pd_mode, assoc->ulpq.pd_mode);
6522 
6523 	if (atomic_read(&sctp_sk(oldsk)->pd_mode)) {
6524 		struct sk_buff_head *queue;
6525 
6526 		/* Decide which queue to move pd_lobby skbs to. */
6527 		if (assoc->ulpq.pd_mode) {
6528 			queue = &newsp->pd_lobby;
6529 		} else
6530 			queue = &newsk->sk_receive_queue;
6531 
6532 		/* Walk through the pd_lobby, looking for skbs that
6533 		 * need moved to the new socket.
6534 		 */
6535 		sctp_skb_for_each(skb, &oldsp->pd_lobby, tmp) {
6536 			event = sctp_skb2event(skb);
6537 			if (event->asoc == assoc) {
6538 				__skb_unlink(skb, &oldsp->pd_lobby);
6539 				__skb_queue_tail(queue, skb);
6540 				sctp_skb_set_owner_r_frag(skb, newsk);
6541 			}
6542 		}
6543 
6544 		/* Clear up any skbs waiting for the partial
6545 		 * delivery to finish.
6546 		 */
6547 		if (assoc->ulpq.pd_mode)
6548 			sctp_clear_pd(oldsk, NULL);
6549 
6550 	}
6551 
6552 	sctp_skb_for_each(skb, &assoc->ulpq.reasm, tmp)
6553 		sctp_skb_set_owner_r_frag(skb, newsk);
6554 
6555 	sctp_skb_for_each(skb, &assoc->ulpq.lobby, tmp)
6556 		sctp_skb_set_owner_r_frag(skb, newsk);
6557 
6558 	/* Set the type of socket to indicate that it is peeled off from the
6559 	 * original UDP-style socket or created with the accept() call on a
6560 	 * TCP-style socket..
6561 	 */
6562 	newsp->type = type;
6563 
6564 	/* Mark the new socket "in-use" by the user so that any packets
6565 	 * that may arrive on the association after we've moved it are
6566 	 * queued to the backlog.  This prevents a potential race between
6567 	 * backlog processing on the old socket and new-packet processing
6568 	 * on the new socket.
6569 	 *
6570 	 * The caller has just allocated newsk so we can guarantee that other
6571 	 * paths won't try to lock it and then oldsk.
6572 	 */
6573 	lock_sock_nested(newsk, SINGLE_DEPTH_NESTING);
6574 	sctp_assoc_migrate(assoc, newsk);
6575 
6576 	/* If the association on the newsk is already closed before accept()
6577 	 * is called, set RCV_SHUTDOWN flag.
6578 	 */
6579 	if (sctp_state(assoc, CLOSED) && sctp_style(newsk, TCP))
6580 		newsk->sk_shutdown |= RCV_SHUTDOWN;
6581 
6582 	newsk->sk_state = SCTP_SS_ESTABLISHED;
6583 	sctp_release_sock(newsk);
6584 }
6585 
6586 
6587 /* This proto struct describes the ULP interface for SCTP.  */
6588 struct proto sctp_prot = {
6589 	.name        =	"SCTP",
6590 	.owner       =	THIS_MODULE,
6591 	.close       =	sctp_close,
6592 	.connect     =	sctp_connect,
6593 	.disconnect  =	sctp_disconnect,
6594 	.accept      =	sctp_accept,
6595 	.ioctl       =	sctp_ioctl,
6596 	.init        =	sctp_init_sock,
6597 	.destroy     =	sctp_destroy_sock,
6598 	.shutdown    =	sctp_shutdown,
6599 	.setsockopt  =	sctp_setsockopt,
6600 	.getsockopt  =	sctp_getsockopt,
6601 	.sendmsg     =	sctp_sendmsg,
6602 	.recvmsg     =	sctp_recvmsg,
6603 	.bind        =	sctp_bind,
6604 	.backlog_rcv =	sctp_backlog_rcv,
6605 	.hash        =	sctp_hash,
6606 	.unhash      =	sctp_unhash,
6607 	.get_port    =	sctp_get_port,
6608 	.obj_size    =  sizeof(struct sctp_sock),
6609 	.sysctl_mem  =  sysctl_sctp_mem,
6610 	.sysctl_rmem =  sysctl_sctp_rmem,
6611 	.sysctl_wmem =  sysctl_sctp_wmem,
6612 	.memory_pressure = &sctp_memory_pressure,
6613 	.enter_memory_pressure = sctp_enter_memory_pressure,
6614 	.memory_allocated = &sctp_memory_allocated,
6615 	.sockets_allocated = &sctp_sockets_allocated,
6616 };
6617 
6618 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6619 
6620 struct proto sctpv6_prot = {
6621 	.name		= "SCTPv6",
6622 	.owner		= THIS_MODULE,
6623 	.close		= sctp_close,
6624 	.connect	= sctp_connect,
6625 	.disconnect	= sctp_disconnect,
6626 	.accept		= sctp_accept,
6627 	.ioctl		= sctp_ioctl,
6628 	.init		= sctp_init_sock,
6629 	.destroy	= sctp_destroy_sock,
6630 	.shutdown	= sctp_shutdown,
6631 	.setsockopt	= sctp_setsockopt,
6632 	.getsockopt	= sctp_getsockopt,
6633 	.sendmsg	= sctp_sendmsg,
6634 	.recvmsg	= sctp_recvmsg,
6635 	.bind		= sctp_bind,
6636 	.backlog_rcv	= sctp_backlog_rcv,
6637 	.hash		= sctp_hash,
6638 	.unhash		= sctp_unhash,
6639 	.get_port	= sctp_get_port,
6640 	.obj_size	= sizeof(struct sctp6_sock),
6641 	.sysctl_mem	= sysctl_sctp_mem,
6642 	.sysctl_rmem	= sysctl_sctp_rmem,
6643 	.sysctl_wmem	= sysctl_sctp_wmem,
6644 	.memory_pressure = &sctp_memory_pressure,
6645 	.enter_memory_pressure = sctp_enter_memory_pressure,
6646 	.memory_allocated = &sctp_memory_allocated,
6647 	.sockets_allocated = &sctp_sockets_allocated,
6648 };
6649 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
6650