aboutsummaryrefslogtreecommitdiffstats
path: root/net/sctp/bind_addr.c
blob: 4ece451c8d27d59ba2a73fba1baf6cb8ca19fe4e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
/* SCTP kernel implementation
 * (C) Copyright IBM Corp. 2001, 2003
 * Copyright (c) Cisco 1999,2000
 * Copyright (c) Motorola 1999,2000,2001
 * Copyright (c) La Monte H.P. Yarroll 2001
 *
 * This file is part of the SCTP kernel implementation.
 *
 * A collection class to handle the storage of transport addresses.
 *
 * This SCTP implementation is free software;
 * you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This SCTP implementation is distributed in the hope that it
 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
 *                 ************************
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU CC; see the file COPYING.  If not, write to
 * the Free Software Foundation, 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
 *    lksctp developers <lksctp-developers@lists.sourceforge.net>
 *
 * Or submit a bug report through the following website:
 *    http://www.sf.net/projects/lksctp
 *
 * Written or modified by:
 *    La Monte H.P. Yarroll <piggy@acm.org>
 *    Karl Knutson          <karl@athena.chicago.il.us>
 *    Jon Grimm             <jgrimm@us.ibm.com>
 *    Daisy Chang           <daisyc@us.ibm.com>
 *
 * Any bugs reported given to us we will try to fix... any fixes shared will
 * be incorporated into the next SCTP release.
 */

#include <linux/types.h>
#include <linux/slab.h>
#include <linux/in.h>
#include <net/sock.h>
#include <net/ipv6.h>
#include <net/if_inet6.h>
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>

/* Forward declarations for internal helpers. */
static int sctp_copy_one_addr(struct sctp_bind_addr *, union sctp_addr *,
			      sctp_scope_t scope, gfp_t gfp,
			      int flags);
static void sctp_bind_addr_clean(struct sctp_bind_addr *);

/* First Level Abstractions. */

/* Copy 'src' to 'dest' taking 'scope' into account.  Omit addresses
 * in 'src' which have a broader scope than 'scope'.
 */
int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
			const struct sctp_bind_addr *src,
			sctp_scope_t scope, gfp_t gfp,
			int flags)
{
	struct sctp_sockaddr_entry *addr;
	int error = 0;

	/* All addresses share the same port.  */
	dest->port = src->port;

	/* Extract the addresses which are relevant for this scope.  */
	list_for_each_entry(addr, &src->address_list, list) {
		error = sctp_copy_one_addr(dest, &addr->a, scope,
					   gfp, flags);
		if (error < 0)
			goto out;
	}

	/* If there are no addresses matching the scope and
	 * this is global scope, try to get a link scope address, with
	 * the assumption that we must be sitting behind a NAT.
	 */
	if (list_empty(&dest->address_list) && (SCTP_SCOPE_GLOBAL == scope)) {
		list_for_each_entry(addr, &src->address_list, list) {
			error = sctp_copy_one_addr(dest, &addr->a,
						   SCTP_SCOPE_LINK, gfp,
						   flags);
			if (error < 0)
				goto out;
		}
	}

out:
	if (error)
		sctp_bind_addr_clean(dest);

	return error;
}

/* Exactly duplicate the address lists.  This is necessary when doing
 * peer-offs and accepts.  We don't want to put all the current system
 * addresses into the endpoint.  That's useless.  But we do want duplicat
 * the list of bound addresses that the older endpoint used.
 */
int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
			const struct sctp_bind_addr *src,
			gfp_t gfp)
{
	struct sctp_sockaddr_entry *addr;
	int error = 0;

	/* All addresses share the same port.  */
	dest->port = src->port;

	list_for_each_entry(addr, &src->address_list, list) {
		error = sctp_add_bind_addr(dest, &addr->a, 1, gfp);
		if (error < 0)
			break;
	}

	return error;
}

/* Initialize the SCTP_bind_addr structure for either an endpoint or
 * an association.
 */
void sctp_bind_addr_init(struct sctp_bind_addr *bp, __u16 port)
{
	bp->malloced = 0;

	INIT_LIST_HEAD(&bp->address_list);
	bp->port = port;
}

/* Dispose of the address list. */
static void sctp_bind_addr_clean(struct sctp_bind_addr *bp)
{
	struct sctp_sockaddr_entry *addr, *temp;

	/* Empty the bind address list. */
	list_for_each_entry_safe(addr, temp, &bp->address_list, list) {
		list_del_rcu(&addr->list);
		kfree_rcu(addr, rcu);
		SCTP_DBG_OBJCNT_DEC(addr);
	}
}

/* Dispose of an SCTP_bind_addr structure  */
void sctp_bind_addr_free(struct sctp_bind_addr *bp)
{
	/* Empty the bind address list. */
	sctp_bind_addr_clean(bp);

	if (bp->malloced) {
		kfree(bp);
		SCTP_DBG_OBJCNT_DEC(bind_addr);
	}
}

/* Add an address to the bind address list in the SCTP_bind_addr structure. */
int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new,
		       __u8 addr_state, gfp_t gfp)
{
	struct sctp_sockaddr_entry *addr;

	/* Add the address to the bind address list.  */
	addr = t_new(struct sctp_sockaddr_entry, gfp);
	if (!addr)
		return -ENOMEM;

	memcpy(&addr->a, new, sizeof(*new));

	/* Fix up the port if it has not yet been set.
	 * Both v4 and v6 have the port at the same offset.
	 */
	if (!addr->a.v4.sin_port)
		addr->a.v4.sin_port = htons(bp->port);

	addr->state = addr_state;
	addr->valid = 1;

	INIT_LIST_HEAD(&addr->list);

	/* We always hold a socket lock when calling this function,
	 * and that acts as a writer synchronizing lock.
	 */
	list_add_tail_rcu(&addr->list, &bp->address_list);
	SCTP_DBG_OBJCNT_INC(addr);

	return 0;
}

/* Delete an address from the bind address list in the SCTP_bind_addr
 * structure.
 */
int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr)
{
	struct sctp_sockaddr_entry *addr, *temp;
	int found = 0;

	/* We hold the socket lock when calling this function,
	 * and that acts as a writer synchronizing lock.
	 */
	list_for_each_entry_safe(addr, temp, &bp->address_list, list) {
		if (sctp_cmp_addr_exact(&addr->a, del_addr)) {
			/* Found the exact match. */
			found = 1;
			addr->valid = 0;
			list_del_rcu(&addr->list);
			break;
		}
	}

	if (found) {
		kfree_rcu(addr, rcu);
		SCTP_DBG_OBJCNT_DEC(addr);
		return 0;
	}

	return -EINVAL;
}

/* Create a network byte-order representation of all the addresses
 * formated as SCTP parameters.
 *
 * The second argument is the return value for the length.
 */
union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
					 int *addrs_len,
					 gfp_t gfp)
{
	union sctp_params addrparms;
	union sctp_params retval;
	int addrparms_len;
	union sctp_addr_param rawaddr;
	int len;
	struct sctp_sockaddr_entry *addr;
	struct list_head *pos;
	struct sctp_af *af;

	addrparms_len = 0;
	len = 0;

	/* Allocate enough memory at once. */
	list_for_each(pos, &bp->address_list) {
		len += sizeof(union sctp_addr_param);
	}

	/* Don't even bother embedding an address if there
	 * is only one.
	 */
	if (len == sizeof(union sctp_addr_param)) {
		retval.v = NULL;
		goto end_raw;
	}

	retval.v = kmalloc(len, gfp);
	if (!retval.v)
		goto end_raw;

	addrparms = retval;

	list_for_each_entry(addr, &bp->address_list, list) {
		af = sctp_get_af_specific(addr->a.v4.sin_family);
		len = af->to_addr_param(&addr->a, &rawaddr);
		memcpy(addrparms.v, &rawaddr, len);
		addrparms.v += len;
		addrparms_len += len;
	}

end_raw:
	*addrs_len = addrparms_len;
	return retval;
}

/*
 * Create an address list out of the raw address list format (IPv4 and IPv6
 * address parameters).
 */
int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw_addr_list,
			   int addrs_len, __u16 port, gfp_t gfp)
{
	union sctp_addr_param *rawaddr;
	struct sctp_paramhdr *param;
	union sctp_addr addr;
	int retval = 0;
	int len;
	struct sctp_af *af;

	/* Convert the raw address to standard address format */
	while (addrs_len) {
		param = (struct sctp_paramhdr *)raw_addr_list;
		rawaddr = (union sctp_addr_param *)raw_addr_list;

		af = sctp_get_af_specific(param_type2af(param->type));
		if (unlikely(!af)) {
			retval = -EINVAL;
			sctp_bind_addr_clean(bp);
			break;
		}

		af->from_addr_param(&addr, rawaddr, htons(port), 0);
		retval = sctp_add_bind_addr(bp, &addr, SCTP_ADDR_SRC, gfp);
		if (retval) {
			/* Can't finish building the list, clean up. */
			sctp_bind_addr_clean(bp);
			break;
		}

		len = ntohs(param->length);
		addrs_len -= len;
		raw_addr_list += len;
	}

	return retval;
}

/********************************************************************
 * 2nd Level Abstractions
 ********************************************************************/

/* Does this contain a specified address?  Allow wildcarding. */
int sctp_bind_addr_match(struct sctp_bind_addr *bp,
			 const union sctp_addr *addr,
			 struct sctp_sock *opt)
{
	struct sctp_sockaddr_entry *laddr;
	int match = 0;

	rcu_read_lock();
	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
		if (!laddr->valid)
			continue;
		if (opt->pf->cmp_addr(&laddr->a, addr, opt)) {
			match = 1;
			break;
		}
	}
	rcu_read_unlock();

	return match;
}

/* Does the address 'addr' conflict with any addresses in
 * the bp.
 */
int sctp_bind_addr_conflict(struct sctp_bind_addr *bp,
			    const union sctp_addr *addr,
			    struct sctp_sock *bp_sp,
			    struct sctp_sock *addr_sp)
{
	struct sctp_sockaddr_entry *laddr;
	int conflict = 0;
	struct sctp_sock *sp;

	/* Pick the IPv6 socket as the basis of comparison
	 * since it's usually a superset of the IPv4.
	 * If there is no IPv6 socket, then default to bind_addr.
	 */
	if (sctp_opt2sk(bp_sp)->sk_family == AF_INET6)
		sp = bp_sp;
	else if (sctp_opt2sk(addr_sp)->sk_family == AF_INET6)
		sp = addr_sp;
	else
		sp = bp_sp;

	rcu_read_lock();
	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
		if (!laddr->valid)
			continue;

		conflict = sp->pf->cmp_addr(&laddr->a, addr, sp);
		if (conflict)
			break;
	}
	rcu_read_unlock();

	return conflict;
}

/* Get the state of the entry in the bind_addr_list */
int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
			 const union sctp_addr *addr)
{
	struct sctp_sockaddr_entry *laddr;
	struct sctp_af *af;
	int state = -1;

	af = sctp_get_af_specific(addr->sa.sa_family);
	if (unlikely(!af))
		return state;

	rcu_read_lock();
	list_for_each_entry_rcu(laddr, &bp->address_list, list) {
		if (!laddr->valid)
			continue;
		if (af->cmp_addr(&laddr->a, addr)) {
			state = laddr->state;
			break;
		}
	}
	rcu_read_unlock();

	return state;
}

/* Find the first address in the bind address list that is not present in
 * the addrs packed array.
 */
union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr	*bp,
					const union sctp_addr	*addrs,
					int			addrcnt,
					struct sctp_sock	*opt)
{
	struct sctp_sockaddr_entry	*laddr;
	union sctp_addr			*addr;
	void 				*addr_buf;
	struct sctp_af			*af;
	int				i;

	/* This is only called sctp_send_asconf_del_ip() and we hold
	 * the socket lock in that code patch, so that address list
	 * can't change.
	 */
	list_for_each_entry(laddr, &bp->address_list, list) {
		addr_buf = (union sctp_addr *)addrs;
		for (i = 0; i < addrcnt; i++) {
			addr = addr_buf;
			af = sctp_get_af_specific(addr->v4.sin_family);
			if (!af)
				break;

			if (opt->pf->cmp_addr(&laddr->a, addr, opt))
				break;

			addr_buf += af->sockaddr_len;
		}
		if (i == addrcnt)
			return &laddr->a;
	}

	return NULL;
}

/* Copy out addresses from the global local address list. */
static int sctp_copy_one_addr(struct sctp_bind_addr *dest,
			      union sctp_addr *addr,
			      sctp_scope_t scope, gfp_t gfp,
			      int flags)
{
	int error = 0;

	if (sctp_is_any(NULL, addr)) {
		error = sctp_copy_local_addr_list(dest, scope, gfp, flags);
	} else if (sctp_in_scope(addr, scope)) {
		/* Now that the address is in scope, check to see if
		 * the address type is supported by local sock as
		 * well as the remote peer.
		 */
		if ((((AF_INET == addr->sa.sa_family) &&
		      (flags & SCTP_ADDR4_PEERSUPP))) ||
		    (((AF_INET6 == addr->sa.sa_family) &&
		      (flags & SCTP_ADDR6_ALLOWED) &&
		      (flags & SCTP_ADDR6_PEERSUPP))))
			error = sctp_add_bind_addr(dest, addr, SCTP_ADDR_SRC,
						    gfp);
	}

	return error;
}

/* Is this a wildcard address?  */
int sctp_is_any(struct sock *sk, const union sctp_addr *addr)
{
	unsigned short fam = 0;
	struct sctp_af *af;

	/* Try to get the right address family */
	if (addr->sa.sa_family != AF_UNSPEC)
		fam = addr->sa.sa_family;
	else if (sk)
		fam = sk->sk_family;

	af = sctp_get_af_specific(fam);
	if (!af)
		return 0;

	return af->is_any(addr);
}

/* Is 'addr' valid for 'scope'?  */
int sctp_in_scope(const union sctp_addr *addr, sctp_scope_t scope)
{
	sctp_scope_t addr_scope = sctp_scope(addr);

	/* The unusable SCTP addresses will not be considered with
	 * any defined scopes.
	 */
	if (SCTP_SCOPE_UNUSABLE == addr_scope)
		return 0;
	/*
	 * For INIT and INIT-ACK address list, let L be the level of
	 * of requested destination address, sender and receiver
	 * SHOULD include all of its addresses with level greater
	 * than or equal to L.
	 *
	 * Address scoping can be selectively controlled via sysctl
	 * option
	 */
	switch (sctp_scope_policy) {
	case SCTP_SCOPE_POLICY_DISABLE:
		return 1;
	case SCTP_SCOPE_POLICY_ENABLE:
		if (addr_scope <= scope)
			return 1;
		break;
	case SCTP_SCOPE_POLICY_PRIVATE:
		if (addr_scope <= scope || SCTP_SCOPE_PRIVATE == addr_scope)
			return 1;
		break;
	case SCTP_SCOPE_POLICY_LINK:
		if (addr_scope <= scope || SCTP_SCOPE_LINK == addr_scope)
			return 1;
		break;
	default:
		break;
	}

	return 0;
}

int sctp_is_ep_boundall(struct sock *sk)
{
	struct sctp_bind_addr *bp;
	struct sctp_sockaddr_entry *addr;

	bp = &sctp_sk(sk)->ep->base.bind_addr;
	if (sctp_list_single_entry(&bp->address_list)) {
		addr = list_entry(bp->address_list.next,
				  struct sctp_sockaddr_entry, list);
		if (sctp_is_any(sk, &addr->a))
			return 1;
	}
	return 0;
}

/********************************************************************
 * 3rd Level Abstractions
 ********************************************************************/

/* What is the scope of 'addr'?  */
sctp_scope_t sctp_scope(const union sctp_addr *addr)
{
	struct sctp_af *af;

	af = sctp_get_af_specific(addr->sa.sa_family);
	if (!af)
		return SCTP_SCOPE_UNUSABLE;

	return af->scope((union sctp_addr *)addr);
}