summaryrefslogtreecommitdiffstats
path: root/net/sctp/diag.c
blob: 0851166b917597b08becf9bf9d5873287b375828 (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
// SPDX-License-Identifier: GPL-2.0-or-later
/* SCTP kernel implementation
 * (C) Copyright Red Hat Inc. 2017
 *
 * This file is part of the SCTP kernel implementation
 *
 * These functions implement sctp diag support.
 *
 * Please send any bug reports or fixes you make to the
 * email addresched(es):
 *    lksctp developers <linux-sctp@vger.kernel.org>
 *
 * Written or modified by:
 *    Xin Long <lucien.xin@gmail.com>
 */

#include <linux/module.h>
#include <linux/inet_diag.h>
#include <linux/sock_diag.h>
#include <net/sctp/sctp.h>

static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
			       void *info);

/* define some functions to make asoc/ep fill look clean */
static void inet_diag_msg_sctpasoc_fill(struct inet_diag_msg *r,
					struct sock *sk,
					struct sctp_association *asoc)
{
	union sctp_addr laddr, paddr;
	struct dst_entry *dst;
	struct timer_list *t3_rtx = &asoc->peer.primary_path->T3_rtx_timer;

	laddr = list_entry(asoc->base.bind_addr.address_list.next,
			   struct sctp_sockaddr_entry, list)->a;
	paddr = asoc->peer.primary_path->ipaddr;
	dst = asoc->peer.primary_path->dst;

	r->idiag_family = sk->sk_family;
	r->id.idiag_sport = htons(asoc->base.bind_addr.port);
	r->id.idiag_dport = htons(asoc->peer.port);
	r->id.idiag_if = dst ? dst->dev->ifindex : 0;
	sock_diag_save_cookie(sk, r->id.idiag_cookie);

#if IS_ENABLED(CONFIG_IPV6)
	if (sk->sk_family == AF_INET6) {
		*(struct in6_addr *)r->id.idiag_src = laddr.v6.sin6_addr;
		*(struct in6_addr *)r->id.idiag_dst = paddr.v6.sin6_addr;
	} else
#endif
	{
		memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
		memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));

		r->id.idiag_src[0] = laddr.v4.sin_addr.s_addr;
		r->id.idiag_dst[0] = paddr.v4.sin_addr.s_addr;
	}

	r->idiag_state = asoc->state;
	if (timer_pending(t3_rtx)) {
		r->idiag_timer = SCTP_EVENT_TIMEOUT_T3_RTX;
		r->idiag_retrans = asoc->rtx_data_chunks;
		r->idiag_expires = jiffies_to_msecs(t3_rtx->expires - jiffies);
	} else {
		r->idiag_timer = 0;
		r->idiag_retrans = 0;
		r->idiag_expires = 0;
	}
}

static int inet_diag_msg_sctpladdrs_fill(struct sk_buff *skb,
					 struct list_head *address_list)
{
	struct sctp_sockaddr_entry *laddr;
	int addrlen = sizeof(struct sockaddr_storage);
	int addrcnt = 0;
	struct nlattr *attr;
	void *info = NULL;

	list_for_each_entry_rcu(laddr, address_list, list)
		addrcnt++;

	attr = nla_reserve(skb, INET_DIAG_LOCALS, addrlen * addrcnt);
	if (!attr)
		return -EMSGSIZE;

	info = nla_data(attr);
	list_for_each_entry_rcu(laddr, address_list, list) {
		memcpy(info, &laddr->a, sizeof(laddr->a));
		memset(info + sizeof(laddr->a), 0, addrlen - sizeof(laddr->a));
		info += addrlen;
	}

	return 0;
}

static int inet_diag_msg_sctpaddrs_fill(struct sk_buff *skb,
					struct sctp_association *asoc)
{
	int addrlen = sizeof(struct sockaddr_storage);
	struct sctp_transport *from;
	struct nlattr *attr;
	void *info = NULL;

	attr = nla_reserve(skb, INET_DIAG_PEERS,
			   addrlen * asoc->peer.transport_count);
	if (!attr)
		return -EMSGSIZE;

	info = nla_data(attr);
	list_for_each_entry(from, &asoc->peer.transport_addr_list,
			    transports) {
		memcpy(info, &from->ipaddr, sizeof(from->ipaddr));
		memset(info + sizeof(from->ipaddr), 0,
		       addrlen - sizeof(from->ipaddr));
		info += addrlen;
	}

	return 0;
}

/* sctp asoc/ep fill*/
static int inet_sctp_diag_fill(struct sock *sk, struct sctp_association *asoc,
			       struct sk_buff *skb,
			       const struct inet_diag_req_v2 *req,
			       struct user_namespace *user_ns,
			       int portid, u32 seq, u16 nlmsg_flags,
			       const struct nlmsghdr *unlh,
			       bool net_admin)
{
	struct sctp_endpoint *ep = sctp_sk(sk)->ep;
	struct list_head *addr_list;
	struct inet_diag_msg *r;
	struct nlmsghdr  *nlh;
	int ext = req->idiag_ext;
	struct sctp_infox infox;
	void *info = NULL;

	nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
			nlmsg_flags);
	if (!nlh)
		return -EMSGSIZE;

	r = nlmsg_data(nlh);
	BUG_ON(!sk_fullsock(sk));

	if (asoc) {
		inet_diag_msg_sctpasoc_fill(r, sk, asoc);
	} else {
		inet_diag_msg_common_fill(r, sk);
		r->idiag_state = sk->sk_state;
		r->idiag_timer = 0;
		r->idiag_retrans = 0;
	}

	if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin))
		goto errout;

	if (ext & (1 << (INET_DIAG_SKMEMINFO - 1))) {
		u32 mem[SK_MEMINFO_VARS];
		int amt;

		if (asoc && asoc->ep->sndbuf_policy)
			amt = asoc->sndbuf_used;
		else
			amt = sk_wmem_alloc_get(sk);
		mem[SK_MEMINFO_WMEM_ALLOC] = amt;
		if (asoc && asoc->ep->rcvbuf_policy)
			amt = atomic_read(&asoc->rmem_alloc);
		else
			amt = sk_rmem_alloc_get(sk);
		mem[SK_MEMINFO_RMEM_ALLOC] = amt;
		mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
		mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
		mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
		mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
		mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
		mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
		mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);

		if (nla_put(skb, INET_DIAG_SKMEMINFO, sizeof(mem), &mem) < 0)
			goto errout;
	}

	if (ext & (1 << (INET_DIAG_INFO - 1))) {
		struct nlattr *attr;

		attr = nla_reserve_64bit(skb, INET_DIAG_INFO,
					 sizeof(struct sctp_info),
					 INET_DIAG_PAD);
		if (!attr)
			goto errout;

		info = nla_data(attr);
	}
	infox.sctpinfo = (struct sctp_info *)info;
	infox.asoc = asoc;
	sctp_diag_get_info(sk, r, &infox);

	addr_list = asoc ? &asoc->base.bind_addr.address_list
			 : &ep->base.bind_addr.address_list;
	if (inet_diag_msg_sctpladdrs_fill(skb, addr_list))
		goto errout;

	if (asoc && (ext & (1 << (INET_DIAG_CONG - 1))))
		if (nla_put_string(skb, INET_DIAG_CONG, "reno") < 0)
			goto errout;

	if (asoc && inet_diag_msg_sctpaddrs_fill(skb, asoc))
		goto errout;

	nlmsg_end(skb, nlh);
	return 0;

errout:
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
}

/* callback and param */
struct sctp_comm_param {
	struct sk_buff *skb;
	struct netlink_callback *cb;
	const struct inet_diag_req_v2 *r;
	const struct nlmsghdr *nlh;
	bool net_admin;
};

static size_t inet_assoc_attr_size(struct sctp_association *asoc)
{
	int addrlen = sizeof(struct sockaddr_storage);
	int addrcnt = 0;
	struct sctp_sockaddr_entry *laddr;

	list_for_each_entry_rcu(laddr, &asoc->base.bind_addr.address_list,
				list)
		addrcnt++;

	return	  nla_total_size(sizeof(struct sctp_info))
		+ nla_total_size(1) /* INET_DIAG_SHUTDOWN */
		+ nla_total_size(1) /* INET_DIAG_TOS */
		+ nla_total_size(1) /* INET_DIAG_TCLASS */
		+ nla_total_size(4) /* INET_DIAG_MARK */
		+ nla_total_size(4) /* INET_DIAG_CLASS_ID */
		+ nla_total_size(addrlen * asoc->peer.transport_count)
		+ nla_total_size(addrlen * addrcnt)
		+ nla_total_size(sizeof(struct inet_diag_meminfo))
		+ nla_total_size(sizeof(struct inet_diag_msg))
		+ 64;
}

static int sctp_tsp_dump_one(struct sctp_transport *tsp, void *p)
{
	struct sctp_association *assoc = tsp->asoc;
	struct sock *sk = tsp->asoc->base.sk;
	struct sctp_comm_param *commp = p;
	struct sk_buff *in_skb = commp->skb;
	const struct inet_diag_req_v2 *req = commp->r;
	const struct nlmsghdr *nlh = commp->nlh;
	struct net *net = sock_net(in_skb->sk);
	struct sk_buff *rep;
	int err;

	err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
	if (err)
		goto out;

	err = -ENOMEM;
	rep = nlmsg_new(inet_assoc_attr_size(assoc), GFP_KERNEL);
	if (!rep)
		goto out;

	lock_sock(sk);
	if (sk != assoc->base.sk) {
		release_sock(sk);
		sk = assoc->base.sk;
		lock_sock(sk);
	}
	err = inet_sctp_diag_fill(sk, assoc, rep, req,
				  sk_user_ns(NETLINK_CB(in_skb).sk),
				  NETLINK_CB(in_skb).portid,
				  nlh->nlmsg_seq, 0, nlh,
				  commp->net_admin);
	release_sock(sk);
	if (err < 0) {
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(rep);
		goto out;
	}

	err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
			      MSG_DONTWAIT);
	if (err > 0)
		err = 0;
out:
	return err;
}

static int sctp_sock_dump(struct sctp_transport *tsp, void *p)
{
	struct sctp_endpoint *ep = tsp->asoc->ep;
	struct sctp_comm_param *commp = p;
	struct sock *sk = ep->base.sk;
	struct sk_buff *skb = commp->skb;
	struct netlink_callback *cb = commp->cb;
	const struct inet_diag_req_v2 *r = commp->r;
	struct sctp_association *assoc;
	int err = 0;

	lock_sock(sk);
	list_for_each_entry(assoc, &ep->asocs, asocs) {
		if (cb->args[4] < cb->args[1])
			goto next;

		if (r->id.idiag_sport != htons(assoc->base.bind_addr.port) &&
		    r->id.idiag_sport)
			goto next;
		if (r->id.idiag_dport != htons(assoc->peer.port) &&
		    r->id.idiag_dport)
			goto next;

		if (!cb->args[3] &&
		    inet_sctp_diag_fill(sk, NULL, skb, r,
					sk_user_ns(NETLINK_CB(cb->skb).sk),
					NETLINK_CB(cb->skb).portid,
					cb->nlh->nlmsg_seq,
					NLM_F_MULTI, cb->nlh,
					commp->net_admin) < 0) {
			err = 1;
			goto release;
		}
		cb->args[3] = 1;

		if (inet_sctp_diag_fill(sk, assoc, skb, r,
					sk_user_ns(NETLINK_CB(cb->skb).sk),
					NETLINK_CB(cb->skb).portid,
					cb->nlh->nlmsg_seq, 0, cb->nlh,
					commp->net_admin) < 0) {
			err = 1;
			goto release;
		}
next:
		cb->args[4]++;
	}
	cb->args[1] = 0;
	cb->args[3] = 0;
	cb->args[4] = 0;
release:
	release_sock(sk);
	return err;
}

static int sctp_sock_filter(struct sctp_transport *tsp, void *p)
{
	struct sctp_endpoint *ep = tsp->asoc->ep;
	struct sctp_comm_param *commp = p;
	struct sock *sk = ep->base.sk;
	const struct inet_diag_req_v2 *r = commp->r;
	struct sctp_association *assoc =
		list_entry(ep->asocs.next, struct sctp_association, asocs);

	/* find the ep only once through the transports by this condition */
	if (tsp->asoc != assoc)
		return 0;

	if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family)
		return 0;

	return 1;
}

static int sctp_ep_dump(struct sctp_endpoint *ep, void *p)
{
	struct sctp_comm_param *commp = p;
	struct sock *sk = ep->base.sk;
	struct sk_buff *skb = commp->skb;
	struct netlink_callback *cb = commp->cb;
	const struct inet_diag_req_v2 *r = commp->r;
	struct net *net = sock_net(skb->sk);
	struct inet_sock *inet = inet_sk(sk);
	int err = 0;

	if (!net_eq(sock_net(sk), net))
		goto out;

	if (cb->args[4] < cb->args[1])
		goto next;

	if (!(r->idiag_states & TCPF_LISTEN) && !list_empty(&ep->asocs))
		goto next;

	if (r->sdiag_family != AF_UNSPEC &&
	    sk->sk_family != r->sdiag_family)
		goto next;

	if (r->id.idiag_sport != inet->inet_sport &&
	    r->id.idiag_sport)
		goto next;

	if (r->id.idiag_dport != inet->inet_dport &&
	    r->id.idiag_dport)
		goto next;

	if (inet_sctp_diag_fill(sk, NULL, skb, r,
				sk_user_ns(NETLINK_CB(cb->skb).sk),
				NETLINK_CB(cb->skb).portid,
				cb->nlh->nlmsg_seq, NLM_F_MULTI,
				cb->nlh, commp->net_admin) < 0) {
		err = 2;
		goto out;
	}
next:
	cb->args[4]++;
out:
	return err;
}

/* define the functions for sctp_diag_handler*/
static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
			       void *info)
{
	struct sctp_infox *infox = (struct sctp_infox *)info;

	if (infox->asoc) {
		r->idiag_rqueue = atomic_read(&infox->asoc->rmem_alloc);
		r->idiag_wqueue = infox->asoc->sndbuf_used;
	} else {
		r->idiag_rqueue = sk->sk_ack_backlog;
		r->idiag_wqueue = sk->sk_max_ack_backlog;
	}
	if (infox->sctpinfo)
		sctp_get_sctp_info(sk, infox->asoc, infox->sctpinfo);
}

static int sctp_diag_dump_one(struct sk_buff *in_skb,
			      const struct nlmsghdr *nlh,
			      const struct inet_diag_req_v2 *req)
{
	struct net *net = sock_net(in_skb->sk);
	union sctp_addr laddr, paddr;
	struct sctp_comm_param commp = {
		.skb = in_skb,
		.r = req,
		.nlh = nlh,
		.net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN),
	};

	if (req->sdiag_family == AF_INET) {
		laddr.v4.sin_port = req->id.idiag_sport;
		laddr.v4.sin_addr.s_addr = req->id.idiag_src[0];
		laddr.v4.sin_family = AF_INET;

		paddr.v4.sin_port = req->id.idiag_dport;
		paddr.v4.sin_addr.s_addr = req->id.idiag_dst[0];
		paddr.v4.sin_family = AF_INET;
	} else {
		laddr.v6.sin6_port = req->id.idiag_sport;
		memcpy(&laddr.v6.sin6_addr, req->id.idiag_src,
		       sizeof(laddr.v6.sin6_addr));
		laddr.v6.sin6_family = AF_INET6;

		paddr.v6.sin6_port = req->id.idiag_dport;
		memcpy(&paddr.v6.sin6_addr, req->id.idiag_dst,
		       sizeof(paddr.v6.sin6_addr));
		paddr.v6.sin6_family = AF_INET6;
	}

	return sctp_transport_lookup_process(sctp_tsp_dump_one,
					     net, &laddr, &paddr, &commp);
}

static void sctp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
			   const struct inet_diag_req_v2 *r, struct nlattr *bc)
{
	u32 idiag_states = r->idiag_states;
	struct net *net = sock_net(skb->sk);
	struct sctp_comm_param commp = {
		.skb = skb,
		.cb = cb,
		.r = r,
		.net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN),
	};
	int pos = cb->args[2];

	/* eps hashtable dumps
	 * args:
	 * 0 : if it will traversal listen sock
	 * 1 : to record the sock pos of this time's traversal
	 * 4 : to work as a temporary variable to traversal list
	 */
	if (cb->args[0] == 0) {
		if (!(idiag_states & TCPF_LISTEN))
			goto skip;
		if (sctp_for_each_endpoint(sctp_ep_dump, &commp))
			goto done;
skip:
		cb->args[0] = 1;
		cb->args[1] = 0;
		cb->args[4] = 0;
	}

	/* asocs by transport hashtable dump
	 * args:
	 * 1 : to record the assoc pos of this time's traversal
	 * 2 : to record the transport pos of this time's traversal
	 * 3 : to mark if we have dumped the ep info of the current asoc
	 * 4 : to work as a temporary variable to traversal list
	 * 5 : to save the sk we get from travelsing the tsp list.
	 */
	if (!(idiag_states & ~(TCPF_LISTEN | TCPF_CLOSE)))
		goto done;

	sctp_for_each_transport(sctp_sock_filter, sctp_sock_dump,
				net, &pos, &commp);
	cb->args[2] = pos;

done:
	cb->args[1] = cb->args[4];
	cb->args[4] = 0;
}

static const struct inet_diag_handler sctp_diag_handler = {
	.dump		 = sctp_diag_dump,
	.dump_one	 = sctp_diag_dump_one,
	.idiag_get_info  = sctp_diag_get_info,
	.idiag_type	 = IPPROTO_SCTP,
	.idiag_info_size = sizeof(struct sctp_info),
};

static int __init sctp_diag_init(void)
{
	return inet_diag_register(&sctp_diag_handler);
}

static void __exit sctp_diag_exit(void)
{
	inet_diag_unregister(&sctp_diag_handler);
}

module_init(sctp_diag_init);
module_exit(sctp_diag_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-132);