1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* SCTP kernel implementation
3 * (C) Copyright Red Hat Inc. 2017
4 *
5 * This file is part of the SCTP kernel implementation
6 *
7 * These functions implement sctp diag support.
8 *
9 * Please send any bug reports or fixes you make to the
10 * email addresched(es):
11 * lksctp developers <linux-sctp@vger.kernel.org>
12 *
13 * Written or modified by:
14 * Xin Long <lucien.xin@gmail.com>
15 */
16
17 #include <linux/module.h>
18 #include <linux/inet_diag.h>
19 #include <linux/sock_diag.h>
20 #include <net/sctp/sctp.h>
21
22 static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
23 void *info);
24
25 /* define some functions to make asoc/ep fill look clean */
inet_diag_msg_sctpasoc_fill(struct inet_diag_msg * r,struct sock * sk,struct sctp_association * asoc)26 static void inet_diag_msg_sctpasoc_fill(struct inet_diag_msg *r,
27 struct sock *sk,
28 struct sctp_association *asoc)
29 {
30 union sctp_addr laddr, paddr;
31 struct dst_entry *dst;
32 struct timer_list *t3_rtx = &asoc->peer.primary_path->T3_rtx_timer;
33
34 laddr = list_entry(asoc->base.bind_addr.address_list.next,
35 struct sctp_sockaddr_entry, list)->a;
36 paddr = asoc->peer.primary_path->ipaddr;
37 dst = asoc->peer.primary_path->dst;
38
39 r->idiag_family = sk->sk_family;
40 r->id.idiag_sport = htons(asoc->base.bind_addr.port);
41 r->id.idiag_dport = htons(asoc->peer.port);
42 r->id.idiag_if = dst ? dst->dev->ifindex : 0;
43 sock_diag_save_cookie(sk, r->id.idiag_cookie);
44
45 #if IS_ENABLED(CONFIG_IPV6)
46 if (sk->sk_family == AF_INET6) {
47 *(struct in6_addr *)r->id.idiag_src = laddr.v6.sin6_addr;
48 *(struct in6_addr *)r->id.idiag_dst = paddr.v6.sin6_addr;
49 } else
50 #endif
51 {
52 memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
53 memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
54
55 r->id.idiag_src[0] = laddr.v4.sin_addr.s_addr;
56 r->id.idiag_dst[0] = paddr.v4.sin_addr.s_addr;
57 }
58
59 r->idiag_state = asoc->state;
60 if (timer_pending(t3_rtx)) {
61 r->idiag_timer = SCTP_EVENT_TIMEOUT_T3_RTX;
62 r->idiag_retrans = asoc->rtx_data_chunks;
63 r->idiag_expires = jiffies_to_msecs(t3_rtx->expires - jiffies);
64 } else {
65 r->idiag_timer = 0;
66 r->idiag_retrans = 0;
67 r->idiag_expires = 0;
68 }
69 }
70
inet_diag_msg_sctpladdrs_fill(struct sk_buff * skb,struct list_head * address_list)71 static int inet_diag_msg_sctpladdrs_fill(struct sk_buff *skb,
72 struct list_head *address_list)
73 {
74 struct sctp_sockaddr_entry *laddr;
75 int addrlen = sizeof(struct sockaddr_storage);
76 int addrcnt = 0;
77 struct nlattr *attr;
78 void *info = NULL;
79
80 list_for_each_entry_rcu(laddr, address_list, list)
81 addrcnt++;
82
83 attr = nla_reserve(skb, INET_DIAG_LOCALS, addrlen * addrcnt);
84 if (!attr)
85 return -EMSGSIZE;
86
87 info = nla_data(attr);
88 list_for_each_entry_rcu(laddr, address_list, list) {
89 memcpy(info, &laddr->a, sizeof(laddr->a));
90 memset(info + sizeof(laddr->a), 0, addrlen - sizeof(laddr->a));
91 info += addrlen;
92 }
93
94 return 0;
95 }
96
inet_diag_msg_sctpaddrs_fill(struct sk_buff * skb,struct sctp_association * asoc)97 static int inet_diag_msg_sctpaddrs_fill(struct sk_buff *skb,
98 struct sctp_association *asoc)
99 {
100 int addrlen = sizeof(struct sockaddr_storage);
101 struct sctp_transport *from;
102 struct nlattr *attr;
103 void *info = NULL;
104
105 attr = nla_reserve(skb, INET_DIAG_PEERS,
106 addrlen * asoc->peer.transport_count);
107 if (!attr)
108 return -EMSGSIZE;
109
110 info = nla_data(attr);
111 list_for_each_entry(from, &asoc->peer.transport_addr_list,
112 transports) {
113 memcpy(info, &from->ipaddr, sizeof(from->ipaddr));
114 memset(info + sizeof(from->ipaddr), 0,
115 addrlen - sizeof(from->ipaddr));
116 info += addrlen;
117 }
118
119 return 0;
120 }
121
122 /* sctp asoc/ep fill*/
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)123 static int inet_sctp_diag_fill(struct sock *sk, struct sctp_association *asoc,
124 struct sk_buff *skb,
125 const struct inet_diag_req_v2 *req,
126 struct user_namespace *user_ns,
127 int portid, u32 seq, u16 nlmsg_flags,
128 const struct nlmsghdr *unlh,
129 bool net_admin)
130 {
131 struct sctp_endpoint *ep = sctp_sk(sk)->ep;
132 struct list_head *addr_list;
133 struct inet_diag_msg *r;
134 struct nlmsghdr *nlh;
135 int ext = req->idiag_ext;
136 struct sctp_infox infox;
137 void *info = NULL;
138
139 nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
140 nlmsg_flags);
141 if (!nlh)
142 return -EMSGSIZE;
143
144 r = nlmsg_data(nlh);
145 BUG_ON(!sk_fullsock(sk));
146
147 if (asoc) {
148 inet_diag_msg_sctpasoc_fill(r, sk, asoc);
149 } else {
150 inet_diag_msg_common_fill(r, sk);
151 r->idiag_state = sk->sk_state;
152 r->idiag_timer = 0;
153 r->idiag_retrans = 0;
154 }
155
156 if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin))
157 goto errout;
158
159 if (ext & (1 << (INET_DIAG_SKMEMINFO - 1))) {
160 u32 mem[SK_MEMINFO_VARS];
161 int amt;
162
163 if (asoc && asoc->ep->sndbuf_policy)
164 amt = asoc->sndbuf_used;
165 else
166 amt = sk_wmem_alloc_get(sk);
167 mem[SK_MEMINFO_WMEM_ALLOC] = amt;
168 if (asoc && asoc->ep->rcvbuf_policy)
169 amt = atomic_read(&asoc->rmem_alloc);
170 else
171 amt = sk_rmem_alloc_get(sk);
172 mem[SK_MEMINFO_RMEM_ALLOC] = amt;
173 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
174 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
175 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
176 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
177 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
178 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
179 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
180
181 if (nla_put(skb, INET_DIAG_SKMEMINFO, sizeof(mem), &mem) < 0)
182 goto errout;
183 }
184
185 if (ext & (1 << (INET_DIAG_INFO - 1))) {
186 struct nlattr *attr;
187
188 attr = nla_reserve_64bit(skb, INET_DIAG_INFO,
189 sizeof(struct sctp_info),
190 INET_DIAG_PAD);
191 if (!attr)
192 goto errout;
193
194 info = nla_data(attr);
195 }
196 infox.sctpinfo = (struct sctp_info *)info;
197 infox.asoc = asoc;
198 sctp_diag_get_info(sk, r, &infox);
199
200 addr_list = asoc ? &asoc->base.bind_addr.address_list
201 : &ep->base.bind_addr.address_list;
202 if (inet_diag_msg_sctpladdrs_fill(skb, addr_list))
203 goto errout;
204
205 if (asoc && (ext & (1 << (INET_DIAG_CONG - 1))))
206 if (nla_put_string(skb, INET_DIAG_CONG, "reno") < 0)
207 goto errout;
208
209 if (asoc && inet_diag_msg_sctpaddrs_fill(skb, asoc))
210 goto errout;
211
212 nlmsg_end(skb, nlh);
213 return 0;
214
215 errout:
216 nlmsg_cancel(skb, nlh);
217 return -EMSGSIZE;
218 }
219
220 /* callback and param */
221 struct sctp_comm_param {
222 struct sk_buff *skb;
223 struct netlink_callback *cb;
224 const struct inet_diag_req_v2 *r;
225 const struct nlmsghdr *nlh;
226 bool net_admin;
227 };
228
inet_assoc_attr_size(struct sctp_association * asoc)229 static size_t inet_assoc_attr_size(struct sctp_association *asoc)
230 {
231 int addrlen = sizeof(struct sockaddr_storage);
232 int addrcnt = 0;
233 struct sctp_sockaddr_entry *laddr;
234
235 list_for_each_entry_rcu(laddr, &asoc->base.bind_addr.address_list,
236 list)
237 addrcnt++;
238
239 return nla_total_size(sizeof(struct sctp_info))
240 + nla_total_size(1) /* INET_DIAG_SHUTDOWN */
241 + nla_total_size(1) /* INET_DIAG_TOS */
242 + nla_total_size(1) /* INET_DIAG_TCLASS */
243 + nla_total_size(4) /* INET_DIAG_MARK */
244 + nla_total_size(4) /* INET_DIAG_CLASS_ID */
245 + nla_total_size(addrlen * asoc->peer.transport_count)
246 + nla_total_size(addrlen * addrcnt)
247 + nla_total_size(sizeof(struct inet_diag_meminfo))
248 + nla_total_size(sizeof(struct inet_diag_msg))
249 + 64;
250 }
251
sctp_tsp_dump_one(struct sctp_transport * tsp,void * p)252 static int sctp_tsp_dump_one(struct sctp_transport *tsp, void *p)
253 {
254 struct sctp_association *assoc = tsp->asoc;
255 struct sock *sk = tsp->asoc->base.sk;
256 struct sctp_comm_param *commp = p;
257 struct sk_buff *in_skb = commp->skb;
258 const struct inet_diag_req_v2 *req = commp->r;
259 const struct nlmsghdr *nlh = commp->nlh;
260 struct net *net = sock_net(in_skb->sk);
261 struct sk_buff *rep;
262 int err;
263
264 err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
265 if (err)
266 goto out;
267
268 err = -ENOMEM;
269 rep = nlmsg_new(inet_assoc_attr_size(assoc), GFP_KERNEL);
270 if (!rep)
271 goto out;
272
273 lock_sock(sk);
274 if (sk != assoc->base.sk) {
275 release_sock(sk);
276 sk = assoc->base.sk;
277 lock_sock(sk);
278 }
279 err = inet_sctp_diag_fill(sk, assoc, rep, req,
280 sk_user_ns(NETLINK_CB(in_skb).sk),
281 NETLINK_CB(in_skb).portid,
282 nlh->nlmsg_seq, 0, nlh,
283 commp->net_admin);
284 release_sock(sk);
285 if (err < 0) {
286 WARN_ON(err == -EMSGSIZE);
287 kfree_skb(rep);
288 goto out;
289 }
290
291 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
292 MSG_DONTWAIT);
293 if (err > 0)
294 err = 0;
295 out:
296 return err;
297 }
298
sctp_sock_dump(struct sctp_transport * tsp,void * p)299 static int sctp_sock_dump(struct sctp_transport *tsp, void *p)
300 {
301 struct sctp_endpoint *ep = tsp->asoc->ep;
302 struct sctp_comm_param *commp = p;
303 struct sock *sk = ep->base.sk;
304 struct sk_buff *skb = commp->skb;
305 struct netlink_callback *cb = commp->cb;
306 const struct inet_diag_req_v2 *r = commp->r;
307 struct sctp_association *assoc;
308 int err = 0;
309
310 lock_sock(sk);
311 list_for_each_entry(assoc, &ep->asocs, asocs) {
312 if (cb->args[4] < cb->args[1])
313 goto next;
314
315 if (r->id.idiag_sport != htons(assoc->base.bind_addr.port) &&
316 r->id.idiag_sport)
317 goto next;
318 if (r->id.idiag_dport != htons(assoc->peer.port) &&
319 r->id.idiag_dport)
320 goto next;
321
322 if (!cb->args[3] &&
323 inet_sctp_diag_fill(sk, NULL, skb, r,
324 sk_user_ns(NETLINK_CB(cb->skb).sk),
325 NETLINK_CB(cb->skb).portid,
326 cb->nlh->nlmsg_seq,
327 NLM_F_MULTI, cb->nlh,
328 commp->net_admin) < 0) {
329 err = 1;
330 goto release;
331 }
332 cb->args[3] = 1;
333
334 if (inet_sctp_diag_fill(sk, assoc, skb, r,
335 sk_user_ns(NETLINK_CB(cb->skb).sk),
336 NETLINK_CB(cb->skb).portid,
337 cb->nlh->nlmsg_seq, 0, cb->nlh,
338 commp->net_admin) < 0) {
339 err = 1;
340 goto release;
341 }
342 next:
343 cb->args[4]++;
344 }
345 cb->args[1] = 0;
346 cb->args[3] = 0;
347 cb->args[4] = 0;
348 release:
349 release_sock(sk);
350 return err;
351 }
352
sctp_sock_filter(struct sctp_transport * tsp,void * p)353 static int sctp_sock_filter(struct sctp_transport *tsp, void *p)
354 {
355 struct sctp_endpoint *ep = tsp->asoc->ep;
356 struct sctp_comm_param *commp = p;
357 struct sock *sk = ep->base.sk;
358 const struct inet_diag_req_v2 *r = commp->r;
359 struct sctp_association *assoc =
360 list_entry(ep->asocs.next, struct sctp_association, asocs);
361
362 /* find the ep only once through the transports by this condition */
363 if (tsp->asoc != assoc)
364 return 0;
365
366 if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family)
367 return 0;
368
369 return 1;
370 }
371
sctp_ep_dump(struct sctp_endpoint * ep,void * p)372 static int sctp_ep_dump(struct sctp_endpoint *ep, void *p)
373 {
374 struct sctp_comm_param *commp = p;
375 struct sock *sk = ep->base.sk;
376 struct sk_buff *skb = commp->skb;
377 struct netlink_callback *cb = commp->cb;
378 const struct inet_diag_req_v2 *r = commp->r;
379 struct net *net = sock_net(skb->sk);
380 struct inet_sock *inet = inet_sk(sk);
381 int err = 0;
382
383 if (!net_eq(sock_net(sk), net))
384 goto out;
385
386 if (cb->args[4] < cb->args[1])
387 goto next;
388
389 if (!(r->idiag_states & TCPF_LISTEN) && !list_empty(&ep->asocs))
390 goto next;
391
392 if (r->sdiag_family != AF_UNSPEC &&
393 sk->sk_family != r->sdiag_family)
394 goto next;
395
396 if (r->id.idiag_sport != inet->inet_sport &&
397 r->id.idiag_sport)
398 goto next;
399
400 if (r->id.idiag_dport != inet->inet_dport &&
401 r->id.idiag_dport)
402 goto next;
403
404 if (inet_sctp_diag_fill(sk, NULL, skb, r,
405 sk_user_ns(NETLINK_CB(cb->skb).sk),
406 NETLINK_CB(cb->skb).portid,
407 cb->nlh->nlmsg_seq, NLM_F_MULTI,
408 cb->nlh, commp->net_admin) < 0) {
409 err = 2;
410 goto out;
411 }
412 next:
413 cb->args[4]++;
414 out:
415 return err;
416 }
417
418 /* define the functions for sctp_diag_handler*/
sctp_diag_get_info(struct sock * sk,struct inet_diag_msg * r,void * info)419 static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
420 void *info)
421 {
422 struct sctp_infox *infox = (struct sctp_infox *)info;
423
424 if (infox->asoc) {
425 r->idiag_rqueue = atomic_read(&infox->asoc->rmem_alloc);
426 r->idiag_wqueue = infox->asoc->sndbuf_used;
427 } else {
428 r->idiag_rqueue = sk->sk_ack_backlog;
429 r->idiag_wqueue = sk->sk_max_ack_backlog;
430 }
431 if (infox->sctpinfo)
432 sctp_get_sctp_info(sk, infox->asoc, infox->sctpinfo);
433 }
434
sctp_diag_dump_one(struct sk_buff * in_skb,const struct nlmsghdr * nlh,const struct inet_diag_req_v2 * req)435 static int sctp_diag_dump_one(struct sk_buff *in_skb,
436 const struct nlmsghdr *nlh,
437 const struct inet_diag_req_v2 *req)
438 {
439 struct net *net = sock_net(in_skb->sk);
440 union sctp_addr laddr, paddr;
441 struct sctp_comm_param commp = {
442 .skb = in_skb,
443 .r = req,
444 .nlh = nlh,
445 .net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN),
446 };
447
448 if (req->sdiag_family == AF_INET) {
449 laddr.v4.sin_port = req->id.idiag_sport;
450 laddr.v4.sin_addr.s_addr = req->id.idiag_src[0];
451 laddr.v4.sin_family = AF_INET;
452
453 paddr.v4.sin_port = req->id.idiag_dport;
454 paddr.v4.sin_addr.s_addr = req->id.idiag_dst[0];
455 paddr.v4.sin_family = AF_INET;
456 } else {
457 laddr.v6.sin6_port = req->id.idiag_sport;
458 memcpy(&laddr.v6.sin6_addr, req->id.idiag_src,
459 sizeof(laddr.v6.sin6_addr));
460 laddr.v6.sin6_family = AF_INET6;
461
462 paddr.v6.sin6_port = req->id.idiag_dport;
463 memcpy(&paddr.v6.sin6_addr, req->id.idiag_dst,
464 sizeof(paddr.v6.sin6_addr));
465 paddr.v6.sin6_family = AF_INET6;
466 }
467
468 return sctp_transport_lookup_process(sctp_tsp_dump_one,
469 net, &laddr, &paddr, &commp);
470 }
471
sctp_diag_dump(struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r,struct nlattr * bc)472 static void sctp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
473 const struct inet_diag_req_v2 *r, struct nlattr *bc)
474 {
475 u32 idiag_states = r->idiag_states;
476 struct net *net = sock_net(skb->sk);
477 struct sctp_comm_param commp = {
478 .skb = skb,
479 .cb = cb,
480 .r = r,
481 .net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN),
482 };
483 int pos = cb->args[2];
484
485 /* eps hashtable dumps
486 * args:
487 * 0 : if it will traversal listen sock
488 * 1 : to record the sock pos of this time's traversal
489 * 4 : to work as a temporary variable to traversal list
490 */
491 if (cb->args[0] == 0) {
492 if (!(idiag_states & TCPF_LISTEN))
493 goto skip;
494 if (sctp_for_each_endpoint(sctp_ep_dump, &commp))
495 goto done;
496 skip:
497 cb->args[0] = 1;
498 cb->args[1] = 0;
499 cb->args[4] = 0;
500 }
501
502 /* asocs by transport hashtable dump
503 * args:
504 * 1 : to record the assoc pos of this time's traversal
505 * 2 : to record the transport pos of this time's traversal
506 * 3 : to mark if we have dumped the ep info of the current asoc
507 * 4 : to work as a temporary variable to traversal list
508 * 5 : to save the sk we get from travelsing the tsp list.
509 */
510 if (!(idiag_states & ~(TCPF_LISTEN | TCPF_CLOSE)))
511 goto done;
512
513 sctp_for_each_transport(sctp_sock_filter, sctp_sock_dump,
514 net, &pos, &commp);
515 cb->args[2] = pos;
516
517 done:
518 cb->args[1] = cb->args[4];
519 cb->args[4] = 0;
520 }
521
522 static const struct inet_diag_handler sctp_diag_handler = {
523 .dump = sctp_diag_dump,
524 .dump_one = sctp_diag_dump_one,
525 .idiag_get_info = sctp_diag_get_info,
526 .idiag_type = IPPROTO_SCTP,
527 .idiag_info_size = sizeof(struct sctp_info),
528 };
529
sctp_diag_init(void)530 static int __init sctp_diag_init(void)
531 {
532 return inet_diag_register(&sctp_diag_handler);
533 }
534
sctp_diag_exit(void)535 static void __exit sctp_diag_exit(void)
536 {
537 inet_diag_unregister(&sctp_diag_handler);
538 }
539
540 module_init(sctp_diag_init);
541 module_exit(sctp_diag_exit);
542 MODULE_LICENSE("GPL");
543 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-132);
544
