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 */ |
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, cookie: 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(timer: 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(j: t3_rtx->expires - jiffies); |
64 | } |
65 | } |
66 | |
67 | static int inet_diag_msg_sctpladdrs_fill(struct sk_buff *skb, |
68 | struct list_head *address_list) |
69 | { |
70 | struct sctp_sockaddr_entry *laddr; |
71 | int addrlen = sizeof(struct sockaddr_storage); |
72 | int addrcnt = 0; |
73 | struct nlattr *attr; |
74 | void *info = NULL; |
75 | |
76 | list_for_each_entry_rcu(laddr, address_list, list) |
77 | addrcnt++; |
78 | |
79 | attr = nla_reserve(skb, attrtype: INET_DIAG_LOCALS, attrlen: addrlen * addrcnt); |
80 | if (!attr) |
81 | return -EMSGSIZE; |
82 | |
83 | info = nla_data(nla: attr); |
84 | list_for_each_entry_rcu(laddr, address_list, list) { |
85 | memcpy(info, &laddr->a, sizeof(laddr->a)); |
86 | memset(info + sizeof(laddr->a), 0, addrlen - sizeof(laddr->a)); |
87 | info += addrlen; |
88 | } |
89 | |
90 | return 0; |
91 | } |
92 | |
93 | static int inet_diag_msg_sctpaddrs_fill(struct sk_buff *skb, |
94 | struct sctp_association *asoc) |
95 | { |
96 | int addrlen = sizeof(struct sockaddr_storage); |
97 | struct sctp_transport *from; |
98 | struct nlattr *attr; |
99 | void *info = NULL; |
100 | |
101 | attr = nla_reserve(skb, attrtype: INET_DIAG_PEERS, |
102 | attrlen: addrlen * asoc->peer.transport_count); |
103 | if (!attr) |
104 | return -EMSGSIZE; |
105 | |
106 | info = nla_data(nla: attr); |
107 | list_for_each_entry(from, &asoc->peer.transport_addr_list, |
108 | transports) { |
109 | memcpy(info, &from->ipaddr, sizeof(from->ipaddr)); |
110 | memset(info + sizeof(from->ipaddr), 0, |
111 | addrlen - sizeof(from->ipaddr)); |
112 | info += addrlen; |
113 | } |
114 | |
115 | return 0; |
116 | } |
117 | |
118 | /* sctp asoc/ep fill*/ |
119 | static int inet_sctp_diag_fill(struct sock *sk, struct sctp_association *asoc, |
120 | struct sk_buff *skb, |
121 | const struct inet_diag_req_v2 *req, |
122 | struct user_namespace *user_ns, |
123 | int portid, u32 seq, u16 nlmsg_flags, |
124 | const struct nlmsghdr *unlh, |
125 | bool net_admin) |
126 | { |
127 | struct sctp_endpoint *ep = sctp_sk(sk)->ep; |
128 | struct list_head *addr_list; |
129 | struct inet_diag_msg *r; |
130 | struct nlmsghdr *nlh; |
131 | int ext = req->idiag_ext; |
132 | struct sctp_infox infox; |
133 | void *info = NULL; |
134 | |
135 | nlh = nlmsg_put(skb, portid, seq, type: unlh->nlmsg_type, payload: sizeof(*r), |
136 | flags: nlmsg_flags); |
137 | if (!nlh) |
138 | return -EMSGSIZE; |
139 | |
140 | r = nlmsg_data(nlh); |
141 | BUG_ON(!sk_fullsock(sk)); |
142 | |
143 | r->idiag_timer = 0; |
144 | r->idiag_retrans = 0; |
145 | r->idiag_expires = 0; |
146 | if (asoc) { |
147 | inet_diag_msg_sctpasoc_fill(r, sk, asoc); |
148 | } else { |
149 | inet_diag_msg_common_fill(r, sk); |
150 | r->idiag_state = sk->sk_state; |
151 | } |
152 | |
153 | if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin)) |
154 | goto errout; |
155 | |
156 | if (ext & (1 << (INET_DIAG_SKMEMINFO - 1))) { |
157 | u32 mem[SK_MEMINFO_VARS]; |
158 | int amt; |
159 | |
160 | if (asoc && asoc->ep->sndbuf_policy) |
161 | amt = asoc->sndbuf_used; |
162 | else |
163 | amt = sk_wmem_alloc_get(sk); |
164 | mem[SK_MEMINFO_WMEM_ALLOC] = amt; |
165 | if (asoc && asoc->ep->rcvbuf_policy) |
166 | amt = atomic_read(v: &asoc->rmem_alloc); |
167 | else |
168 | amt = sk_rmem_alloc_get(sk); |
169 | mem[SK_MEMINFO_RMEM_ALLOC] = amt; |
170 | mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf; |
171 | mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf; |
172 | mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; |
173 | mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued; |
174 | mem[SK_MEMINFO_OPTMEM] = atomic_read(v: &sk->sk_omem_alloc); |
175 | mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len); |
176 | mem[SK_MEMINFO_DROPS] = atomic_read(v: &sk->sk_drops); |
177 | |
178 | if (nla_put(skb, attrtype: INET_DIAG_SKMEMINFO, attrlen: sizeof(mem), data: &mem) < 0) |
179 | goto errout; |
180 | } |
181 | |
182 | if (ext & (1 << (INET_DIAG_INFO - 1))) { |
183 | struct nlattr *attr; |
184 | |
185 | attr = nla_reserve_64bit(skb, attrtype: INET_DIAG_INFO, |
186 | attrlen: sizeof(struct sctp_info), |
187 | padattr: INET_DIAG_PAD); |
188 | if (!attr) |
189 | goto errout; |
190 | |
191 | info = nla_data(nla: attr); |
192 | } |
193 | infox.sctpinfo = (struct sctp_info *)info; |
194 | infox.asoc = asoc; |
195 | sctp_diag_get_info(sk, r, info: &infox); |
196 | |
197 | addr_list = asoc ? &asoc->base.bind_addr.address_list |
198 | : &ep->base.bind_addr.address_list; |
199 | if (inet_diag_msg_sctpladdrs_fill(skb, address_list: addr_list)) |
200 | goto errout; |
201 | |
202 | if (asoc && (ext & (1 << (INET_DIAG_CONG - 1)))) |
203 | if (nla_put_string(skb, attrtype: INET_DIAG_CONG, str: "reno" ) < 0) |
204 | goto errout; |
205 | |
206 | if (asoc && inet_diag_msg_sctpaddrs_fill(skb, asoc)) |
207 | goto errout; |
208 | |
209 | nlmsg_end(skb, nlh); |
210 | return 0; |
211 | |
212 | errout: |
213 | nlmsg_cancel(skb, nlh); |
214 | return -EMSGSIZE; |
215 | } |
216 | |
217 | /* callback and param */ |
218 | struct sctp_comm_param { |
219 | struct sk_buff *skb; |
220 | struct netlink_callback *cb; |
221 | const struct inet_diag_req_v2 *r; |
222 | const struct nlmsghdr *nlh; |
223 | bool net_admin; |
224 | }; |
225 | |
226 | static size_t inet_assoc_attr_size(struct sctp_association *asoc) |
227 | { |
228 | int addrlen = sizeof(struct sockaddr_storage); |
229 | int addrcnt = 0; |
230 | struct sctp_sockaddr_entry *laddr; |
231 | |
232 | list_for_each_entry_rcu(laddr, &asoc->base.bind_addr.address_list, |
233 | list) |
234 | addrcnt++; |
235 | |
236 | return nla_total_size(payload: sizeof(struct sctp_info)) |
237 | + nla_total_size(payload: addrlen * asoc->peer.transport_count) |
238 | + nla_total_size(payload: addrlen * addrcnt) |
239 | + nla_total_size(payload: sizeof(struct inet_diag_msg)) |
240 | + inet_diag_msg_attrs_size() |
241 | + nla_total_size(payload: sizeof(struct inet_diag_meminfo)) |
242 | + 64; |
243 | } |
244 | |
245 | static int sctp_sock_dump_one(struct sctp_endpoint *ep, struct sctp_transport *tsp, void *p) |
246 | { |
247 | struct sctp_association *assoc = tsp->asoc; |
248 | struct sctp_comm_param *commp = p; |
249 | struct sock *sk = ep->base.sk; |
250 | const struct inet_diag_req_v2 *req = commp->r; |
251 | struct sk_buff *skb = commp->skb; |
252 | struct sk_buff *rep; |
253 | int err; |
254 | |
255 | err = sock_diag_check_cookie(sk, cookie: req->id.idiag_cookie); |
256 | if (err) |
257 | return err; |
258 | |
259 | rep = nlmsg_new(payload: inet_assoc_attr_size(asoc: assoc), GFP_KERNEL); |
260 | if (!rep) |
261 | return -ENOMEM; |
262 | |
263 | lock_sock(sk); |
264 | if (ep != assoc->ep) { |
265 | err = -EAGAIN; |
266 | goto out; |
267 | } |
268 | |
269 | err = inet_sctp_diag_fill(sk, asoc: assoc, skb: rep, req, user_ns: sk_user_ns(NETLINK_CB(skb).sk), |
270 | NETLINK_CB(skb).portid, seq: commp->nlh->nlmsg_seq, nlmsg_flags: 0, |
271 | unlh: commp->nlh, net_admin: commp->net_admin); |
272 | if (err < 0) { |
273 | WARN_ON(err == -EMSGSIZE); |
274 | goto out; |
275 | } |
276 | release_sock(sk); |
277 | |
278 | return nlmsg_unicast(sk: sock_net(sk: skb->sk)->diag_nlsk, skb: rep, NETLINK_CB(skb).portid); |
279 | |
280 | out: |
281 | release_sock(sk); |
282 | kfree_skb(skb: rep); |
283 | return err; |
284 | } |
285 | |
286 | static int sctp_sock_dump(struct sctp_endpoint *ep, struct sctp_transport *tsp, void *p) |
287 | { |
288 | struct sctp_comm_param *commp = p; |
289 | struct sock *sk = ep->base.sk; |
290 | struct sk_buff *skb = commp->skb; |
291 | struct netlink_callback *cb = commp->cb; |
292 | const struct inet_diag_req_v2 *r = commp->r; |
293 | struct sctp_association *assoc; |
294 | int err = 0; |
295 | |
296 | lock_sock(sk); |
297 | if (ep != tsp->asoc->ep) |
298 | goto release; |
299 | list_for_each_entry(assoc, &ep->asocs, asocs) { |
300 | if (cb->args[4] < cb->args[1]) |
301 | goto next; |
302 | |
303 | if (r->id.idiag_sport != htons(assoc->base.bind_addr.port) && |
304 | r->id.idiag_sport) |
305 | goto next; |
306 | if (r->id.idiag_dport != htons(assoc->peer.port) && |
307 | r->id.idiag_dport) |
308 | goto next; |
309 | |
310 | if (!cb->args[3] && |
311 | inet_sctp_diag_fill(sk, NULL, skb, req: r, |
312 | user_ns: sk_user_ns(NETLINK_CB(cb->skb).sk), |
313 | NETLINK_CB(cb->skb).portid, |
314 | seq: cb->nlh->nlmsg_seq, |
315 | NLM_F_MULTI, unlh: cb->nlh, |
316 | net_admin: commp->net_admin) < 0) { |
317 | err = 1; |
318 | goto release; |
319 | } |
320 | cb->args[3] = 1; |
321 | |
322 | if (inet_sctp_diag_fill(sk, asoc: assoc, skb, req: r, |
323 | user_ns: sk_user_ns(NETLINK_CB(cb->skb).sk), |
324 | NETLINK_CB(cb->skb).portid, |
325 | seq: cb->nlh->nlmsg_seq, nlmsg_flags: 0, unlh: cb->nlh, |
326 | net_admin: commp->net_admin) < 0) { |
327 | err = 1; |
328 | goto release; |
329 | } |
330 | next: |
331 | cb->args[4]++; |
332 | } |
333 | cb->args[1] = 0; |
334 | cb->args[3] = 0; |
335 | cb->args[4] = 0; |
336 | release: |
337 | release_sock(sk); |
338 | return err; |
339 | } |
340 | |
341 | static int sctp_sock_filter(struct sctp_endpoint *ep, struct sctp_transport *tsp, void *p) |
342 | { |
343 | struct sctp_comm_param *commp = p; |
344 | struct sock *sk = ep->base.sk; |
345 | const struct inet_diag_req_v2 *r = commp->r; |
346 | |
347 | /* find the ep only once through the transports by this condition */ |
348 | if (!list_is_first(list: &tsp->asoc->asocs, head: &ep->asocs)) |
349 | return 0; |
350 | |
351 | if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family) |
352 | return 0; |
353 | |
354 | return 1; |
355 | } |
356 | |
357 | static int sctp_ep_dump(struct sctp_endpoint *ep, void *p) |
358 | { |
359 | struct sctp_comm_param *commp = p; |
360 | struct sock *sk = ep->base.sk; |
361 | struct sk_buff *skb = commp->skb; |
362 | struct netlink_callback *cb = commp->cb; |
363 | const struct inet_diag_req_v2 *r = commp->r; |
364 | struct net *net = sock_net(sk: skb->sk); |
365 | struct inet_sock *inet = inet_sk(sk); |
366 | int err = 0; |
367 | |
368 | if (!net_eq(net1: sock_net(sk), net2: net)) |
369 | goto out; |
370 | |
371 | if (cb->args[4] < cb->args[1]) |
372 | goto next; |
373 | |
374 | if (!(r->idiag_states & TCPF_LISTEN) && !list_empty(head: &ep->asocs)) |
375 | goto next; |
376 | |
377 | if (r->sdiag_family != AF_UNSPEC && |
378 | sk->sk_family != r->sdiag_family) |
379 | goto next; |
380 | |
381 | if (r->id.idiag_sport != inet->inet_sport && |
382 | r->id.idiag_sport) |
383 | goto next; |
384 | |
385 | if (r->id.idiag_dport != inet->inet_dport && |
386 | r->id.idiag_dport) |
387 | goto next; |
388 | |
389 | if (inet_sctp_diag_fill(sk, NULL, skb, req: r, |
390 | user_ns: sk_user_ns(NETLINK_CB(cb->skb).sk), |
391 | NETLINK_CB(cb->skb).portid, |
392 | seq: cb->nlh->nlmsg_seq, NLM_F_MULTI, |
393 | unlh: cb->nlh, net_admin: commp->net_admin) < 0) { |
394 | err = 2; |
395 | goto out; |
396 | } |
397 | next: |
398 | cb->args[4]++; |
399 | out: |
400 | return err; |
401 | } |
402 | |
403 | /* define the functions for sctp_diag_handler*/ |
404 | static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, |
405 | void *info) |
406 | { |
407 | struct sctp_infox *infox = (struct sctp_infox *)info; |
408 | |
409 | if (infox->asoc) { |
410 | r->idiag_rqueue = atomic_read(v: &infox->asoc->rmem_alloc); |
411 | r->idiag_wqueue = infox->asoc->sndbuf_used; |
412 | } else { |
413 | r->idiag_rqueue = READ_ONCE(sk->sk_ack_backlog); |
414 | r->idiag_wqueue = READ_ONCE(sk->sk_max_ack_backlog); |
415 | } |
416 | if (infox->sctpinfo) |
417 | sctp_get_sctp_info(sk, asoc: infox->asoc, info: infox->sctpinfo); |
418 | } |
419 | |
420 | static int sctp_diag_dump_one(struct netlink_callback *cb, |
421 | const struct inet_diag_req_v2 *req) |
422 | { |
423 | struct sk_buff *skb = cb->skb; |
424 | struct net *net = sock_net(sk: skb->sk); |
425 | const struct nlmsghdr *nlh = cb->nlh; |
426 | union sctp_addr laddr, paddr; |
427 | int dif = req->id.idiag_if; |
428 | struct sctp_comm_param commp = { |
429 | .skb = skb, |
430 | .r = req, |
431 | .nlh = nlh, |
432 | .net_admin = netlink_net_capable(skb, CAP_NET_ADMIN), |
433 | }; |
434 | |
435 | if (req->sdiag_family == AF_INET) { |
436 | laddr.v4.sin_port = req->id.idiag_sport; |
437 | laddr.v4.sin_addr.s_addr = req->id.idiag_src[0]; |
438 | laddr.v4.sin_family = AF_INET; |
439 | |
440 | paddr.v4.sin_port = req->id.idiag_dport; |
441 | paddr.v4.sin_addr.s_addr = req->id.idiag_dst[0]; |
442 | paddr.v4.sin_family = AF_INET; |
443 | } else { |
444 | laddr.v6.sin6_port = req->id.idiag_sport; |
445 | memcpy(&laddr.v6.sin6_addr, req->id.idiag_src, |
446 | sizeof(laddr.v6.sin6_addr)); |
447 | laddr.v6.sin6_family = AF_INET6; |
448 | |
449 | paddr.v6.sin6_port = req->id.idiag_dport; |
450 | memcpy(&paddr.v6.sin6_addr, req->id.idiag_dst, |
451 | sizeof(paddr.v6.sin6_addr)); |
452 | paddr.v6.sin6_family = AF_INET6; |
453 | } |
454 | |
455 | return sctp_transport_lookup_process(cb: sctp_sock_dump_one, |
456 | net, laddr: &laddr, paddr: &paddr, p: &commp, dif); |
457 | } |
458 | |
459 | static void sctp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, |
460 | const struct inet_diag_req_v2 *r) |
461 | { |
462 | u32 idiag_states = r->idiag_states; |
463 | struct net *net = sock_net(sk: skb->sk); |
464 | struct sctp_comm_param commp = { |
465 | .skb = skb, |
466 | .cb = cb, |
467 | .r = r, |
468 | .net_admin = netlink_net_capable(skb: cb->skb, CAP_NET_ADMIN), |
469 | }; |
470 | int pos = cb->args[2]; |
471 | |
472 | /* eps hashtable dumps |
473 | * args: |
474 | * 0 : if it will traversal listen sock |
475 | * 1 : to record the sock pos of this time's traversal |
476 | * 4 : to work as a temporary variable to traversal list |
477 | */ |
478 | if (cb->args[0] == 0) { |
479 | if (!(idiag_states & TCPF_LISTEN)) |
480 | goto skip; |
481 | if (sctp_for_each_endpoint(cb: sctp_ep_dump, p: &commp)) |
482 | goto done; |
483 | skip: |
484 | cb->args[0] = 1; |
485 | cb->args[1] = 0; |
486 | cb->args[4] = 0; |
487 | } |
488 | |
489 | /* asocs by transport hashtable dump |
490 | * args: |
491 | * 1 : to record the assoc pos of this time's traversal |
492 | * 2 : to record the transport pos of this time's traversal |
493 | * 3 : to mark if we have dumped the ep info of the current asoc |
494 | * 4 : to work as a temporary variable to traversal list |
495 | * 5 : to save the sk we get from travelsing the tsp list. |
496 | */ |
497 | if (!(idiag_states & ~(TCPF_LISTEN | TCPF_CLOSE))) |
498 | goto done; |
499 | |
500 | sctp_transport_traverse_process(cb: sctp_sock_filter, cb_done: sctp_sock_dump, |
501 | net, pos: &pos, p: &commp); |
502 | cb->args[2] = pos; |
503 | |
504 | done: |
505 | cb->args[1] = cb->args[4]; |
506 | cb->args[4] = 0; |
507 | } |
508 | |
509 | static const struct inet_diag_handler sctp_diag_handler = { |
510 | .dump = sctp_diag_dump, |
511 | .dump_one = sctp_diag_dump_one, |
512 | .idiag_get_info = sctp_diag_get_info, |
513 | .idiag_type = IPPROTO_SCTP, |
514 | .idiag_info_size = sizeof(struct sctp_info), |
515 | }; |
516 | |
517 | static int __init sctp_diag_init(void) |
518 | { |
519 | return inet_diag_register(handler: &sctp_diag_handler); |
520 | } |
521 | |
522 | static void __exit sctp_diag_exit(void) |
523 | { |
524 | inet_diag_unregister(handler: &sctp_diag_handler); |
525 | } |
526 | |
527 | module_init(sctp_diag_init); |
528 | module_exit(sctp_diag_exit); |
529 | MODULE_LICENSE("GPL" ); |
530 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-132); |
531 | |