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Merge tag 'ktest-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...
[mirror_ubuntu-hirsute-kernel.git] / net / netfilter / nf_conntrack_proto_sctp.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Connection tracking protocol helper module for SCTP.
4 *
5 * Copyright (c) 2004 Kiran Kumar Immidi <immidi_kiran@yahoo.com>
6 * Copyright (c) 2004-2012 Patrick McHardy <kaber@trash.net>
7 *
8 * SCTP is defined in RFC 2960. References to various sections in this code
9 * are to this RFC.
10 */
11
12 #include <linux/types.h>
13 #include <linux/timer.h>
14 #include <linux/netfilter.h>
15 #include <linux/in.h>
16 #include <linux/ip.h>
17 #include <linux/sctp.h>
18 #include <linux/string.h>
19 #include <linux/seq_file.h>
20 #include <linux/spinlock.h>
21 #include <linux/interrupt.h>
22 #include <net/sctp/checksum.h>
23
24 #include <net/netfilter/nf_log.h>
25 #include <net/netfilter/nf_conntrack.h>
26 #include <net/netfilter/nf_conntrack_l4proto.h>
27 #include <net/netfilter/nf_conntrack_ecache.h>
28 #include <net/netfilter/nf_conntrack_timeout.h>
29
30 /* FIXME: Examine ipfilter's timeouts and conntrack transitions more
31 closely. They're more complex. --RR
32
33 And so for me for SCTP :D -Kiran */
34
35 static const char *const sctp_conntrack_names[] = {
36 "NONE",
37 "CLOSED",
38 "COOKIE_WAIT",
39 "COOKIE_ECHOED",
40 "ESTABLISHED",
41 "SHUTDOWN_SENT",
42 "SHUTDOWN_RECD",
43 "SHUTDOWN_ACK_SENT",
44 "HEARTBEAT_SENT",
45 "HEARTBEAT_ACKED",
46 };
47
48 #define SECS * HZ
49 #define MINS * 60 SECS
50 #define HOURS * 60 MINS
51 #define DAYS * 24 HOURS
52
53 static const unsigned int sctp_timeouts[SCTP_CONNTRACK_MAX] = {
54 [SCTP_CONNTRACK_CLOSED] = 10 SECS,
55 [SCTP_CONNTRACK_COOKIE_WAIT] = 3 SECS,
56 [SCTP_CONNTRACK_COOKIE_ECHOED] = 3 SECS,
57 [SCTP_CONNTRACK_ESTABLISHED] = 5 DAYS,
58 [SCTP_CONNTRACK_SHUTDOWN_SENT] = 300 SECS / 1000,
59 [SCTP_CONNTRACK_SHUTDOWN_RECD] = 300 SECS / 1000,
60 [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT] = 3 SECS,
61 [SCTP_CONNTRACK_HEARTBEAT_SENT] = 30 SECS,
62 [SCTP_CONNTRACK_HEARTBEAT_ACKED] = 210 SECS,
63 };
64
65 #define SCTP_FLAG_HEARTBEAT_VTAG_FAILED 1
66
67 #define sNO SCTP_CONNTRACK_NONE
68 #define sCL SCTP_CONNTRACK_CLOSED
69 #define sCW SCTP_CONNTRACK_COOKIE_WAIT
70 #define sCE SCTP_CONNTRACK_COOKIE_ECHOED
71 #define sES SCTP_CONNTRACK_ESTABLISHED
72 #define sSS SCTP_CONNTRACK_SHUTDOWN_SENT
73 #define sSR SCTP_CONNTRACK_SHUTDOWN_RECD
74 #define sSA SCTP_CONNTRACK_SHUTDOWN_ACK_SENT
75 #define sHS SCTP_CONNTRACK_HEARTBEAT_SENT
76 #define sHA SCTP_CONNTRACK_HEARTBEAT_ACKED
77 #define sIV SCTP_CONNTRACK_MAX
78
79 /*
80 These are the descriptions of the states:
81
82 NOTE: These state names are tantalizingly similar to the states of an
83 SCTP endpoint. But the interpretation of the states is a little different,
84 considering that these are the states of the connection and not of an end
85 point. Please note the subtleties. -Kiran
86
87 NONE - Nothing so far.
88 COOKIE WAIT - We have seen an INIT chunk in the original direction, or also
89 an INIT_ACK chunk in the reply direction.
90 COOKIE ECHOED - We have seen a COOKIE_ECHO chunk in the original direction.
91 ESTABLISHED - We have seen a COOKIE_ACK in the reply direction.
92 SHUTDOWN_SENT - We have seen a SHUTDOWN chunk in the original direction.
93 SHUTDOWN_RECD - We have seen a SHUTDOWN chunk in the reply directoin.
94 SHUTDOWN_ACK_SENT - We have seen a SHUTDOWN_ACK chunk in the direction opposite
95 to that of the SHUTDOWN chunk.
96 CLOSED - We have seen a SHUTDOWN_COMPLETE chunk in the direction of
97 the SHUTDOWN chunk. Connection is closed.
98 HEARTBEAT_SENT - We have seen a HEARTBEAT in a new flow.
99 HEARTBEAT_ACKED - We have seen a HEARTBEAT-ACK in the direction opposite to
100 that of the HEARTBEAT chunk. Secondary connection is
101 established.
102 */
103
104 /* TODO
105 - I have assumed that the first INIT is in the original direction.
106 This messes things when an INIT comes in the reply direction in CLOSED
107 state.
108 - Check the error type in the reply dir before transitioning from
109 cookie echoed to closed.
110 - Sec 5.2.4 of RFC 2960
111 - Full Multi Homing support.
112 */
113
114 /* SCTP conntrack state transitions */
115 static const u8 sctp_conntracks[2][11][SCTP_CONNTRACK_MAX] = {
116 {
117 /* ORIGINAL */
118 /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA */
119 /* init */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCW, sHA},
120 /* init_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},
121 /* abort */ {sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL},
122 /* shutdown */ {sCL, sCL, sCW, sCE, sSS, sSS, sSR, sSA, sCL, sSS},
123 /* shutdown_ack */ {sSA, sCL, sCW, sCE, sES, sSA, sSA, sSA, sSA, sHA},
124 /* error */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* Can't have Stale cookie*/
125 /* cookie_echo */ {sCL, sCL, sCE, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* 5.2.4 - Big TODO */
126 /* cookie_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* Can't come in orig dir */
127 /* shutdown_comp*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sCL, sCL, sHA},
128 /* heartbeat */ {sHS, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA},
129 /* heartbeat_ack*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA}
130 },
131 {
132 /* REPLY */
133 /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA */
134 /* init */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},/* INIT in sCL Big TODO */
135 /* init_ack */ {sIV, sCW, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},
136 /* abort */ {sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sIV, sCL},
137 /* shutdown */ {sIV, sCL, sCW, sCE, sSR, sSS, sSR, sSA, sIV, sSR},
138 /* shutdown_ack */ {sIV, sCL, sCW, sCE, sES, sSA, sSA, sSA, sIV, sHA},
139 /* error */ {sIV, sCL, sCW, sCL, sES, sSS, sSR, sSA, sIV, sHA},
140 /* cookie_echo */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},/* Can't come in reply dir */
141 /* cookie_ack */ {sIV, sCL, sCW, sES, sES, sSS, sSR, sSA, sIV, sHA},
142 /* shutdown_comp*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sCL, sIV, sHA},
143 /* heartbeat */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA},
144 /* heartbeat_ack*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHA, sHA}
145 }
146 };
147
148 #ifdef CONFIG_NF_CONNTRACK_PROCFS
149 /* Print out the private part of the conntrack. */
150 static void sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
151 {
152 seq_printf(s, "%s ", sctp_conntrack_names[ct->proto.sctp.state]);
153 }
154 #endif
155
156 #define for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) \
157 for ((offset) = (dataoff) + sizeof(struct sctphdr), (count) = 0; \
158 (offset) < (skb)->len && \
159 ((sch) = skb_header_pointer((skb), (offset), sizeof(_sch), &(_sch))); \
160 (offset) += (ntohs((sch)->length) + 3) & ~3, (count)++)
161
162 /* Some validity checks to make sure the chunks are fine */
163 static int do_basic_checks(struct nf_conn *ct,
164 const struct sk_buff *skb,
165 unsigned int dataoff,
166 unsigned long *map)
167 {
168 u_int32_t offset, count;
169 struct sctp_chunkhdr _sch, *sch;
170 int flag;
171
172 flag = 0;
173
174 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
175 pr_debug("Chunk Num: %d Type: %d\n", count, sch->type);
176
177 if (sch->type == SCTP_CID_INIT ||
178 sch->type == SCTP_CID_INIT_ACK ||
179 sch->type == SCTP_CID_SHUTDOWN_COMPLETE)
180 flag = 1;
181
182 /*
183 * Cookie Ack/Echo chunks not the first OR
184 * Init / Init Ack / Shutdown compl chunks not the only chunks
185 * OR zero-length.
186 */
187 if (((sch->type == SCTP_CID_COOKIE_ACK ||
188 sch->type == SCTP_CID_COOKIE_ECHO ||
189 flag) &&
190 count != 0) || !sch->length) {
191 pr_debug("Basic checks failed\n");
192 return 1;
193 }
194
195 if (map)
196 set_bit(sch->type, map);
197 }
198
199 pr_debug("Basic checks passed\n");
200 return count == 0;
201 }
202
203 static int sctp_new_state(enum ip_conntrack_dir dir,
204 enum sctp_conntrack cur_state,
205 int chunk_type)
206 {
207 int i;
208
209 pr_debug("Chunk type: %d\n", chunk_type);
210
211 switch (chunk_type) {
212 case SCTP_CID_INIT:
213 pr_debug("SCTP_CID_INIT\n");
214 i = 0;
215 break;
216 case SCTP_CID_INIT_ACK:
217 pr_debug("SCTP_CID_INIT_ACK\n");
218 i = 1;
219 break;
220 case SCTP_CID_ABORT:
221 pr_debug("SCTP_CID_ABORT\n");
222 i = 2;
223 break;
224 case SCTP_CID_SHUTDOWN:
225 pr_debug("SCTP_CID_SHUTDOWN\n");
226 i = 3;
227 break;
228 case SCTP_CID_SHUTDOWN_ACK:
229 pr_debug("SCTP_CID_SHUTDOWN_ACK\n");
230 i = 4;
231 break;
232 case SCTP_CID_ERROR:
233 pr_debug("SCTP_CID_ERROR\n");
234 i = 5;
235 break;
236 case SCTP_CID_COOKIE_ECHO:
237 pr_debug("SCTP_CID_COOKIE_ECHO\n");
238 i = 6;
239 break;
240 case SCTP_CID_COOKIE_ACK:
241 pr_debug("SCTP_CID_COOKIE_ACK\n");
242 i = 7;
243 break;
244 case SCTP_CID_SHUTDOWN_COMPLETE:
245 pr_debug("SCTP_CID_SHUTDOWN_COMPLETE\n");
246 i = 8;
247 break;
248 case SCTP_CID_HEARTBEAT:
249 pr_debug("SCTP_CID_HEARTBEAT");
250 i = 9;
251 break;
252 case SCTP_CID_HEARTBEAT_ACK:
253 pr_debug("SCTP_CID_HEARTBEAT_ACK");
254 i = 10;
255 break;
256 default:
257 /* Other chunks like DATA or SACK do not change the state */
258 pr_debug("Unknown chunk type, Will stay in %s\n",
259 sctp_conntrack_names[cur_state]);
260 return cur_state;
261 }
262
263 pr_debug("dir: %d cur_state: %s chunk_type: %d new_state: %s\n",
264 dir, sctp_conntrack_names[cur_state], chunk_type,
265 sctp_conntrack_names[sctp_conntracks[dir][i][cur_state]]);
266
267 return sctp_conntracks[dir][i][cur_state];
268 }
269
270 /* Don't need lock here: this conntrack not in circulation yet */
271 static noinline bool
272 sctp_new(struct nf_conn *ct, const struct sk_buff *skb,
273 const struct sctphdr *sh, unsigned int dataoff)
274 {
275 enum sctp_conntrack new_state;
276 const struct sctp_chunkhdr *sch;
277 struct sctp_chunkhdr _sch;
278 u32 offset, count;
279
280 memset(&ct->proto.sctp, 0, sizeof(ct->proto.sctp));
281 new_state = SCTP_CONNTRACK_MAX;
282 for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) {
283 new_state = sctp_new_state(IP_CT_DIR_ORIGINAL,
284 SCTP_CONNTRACK_NONE, sch->type);
285
286 /* Invalid: delete conntrack */
287 if (new_state == SCTP_CONNTRACK_NONE ||
288 new_state == SCTP_CONNTRACK_MAX) {
289 pr_debug("nf_conntrack_sctp: invalid new deleting.\n");
290 return false;
291 }
292
293 /* Copy the vtag into the state info */
294 if (sch->type == SCTP_CID_INIT) {
295 struct sctp_inithdr _inithdr, *ih;
296 /* Sec 8.5.1 (A) */
297 if (sh->vtag)
298 return false;
299
300 ih = skb_header_pointer(skb, offset + sizeof(_sch),
301 sizeof(_inithdr), &_inithdr);
302 if (!ih)
303 return false;
304
305 pr_debug("Setting vtag %x for new conn\n",
306 ih->init_tag);
307
308 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = ih->init_tag;
309 } else if (sch->type == SCTP_CID_HEARTBEAT) {
310 pr_debug("Setting vtag %x for secondary conntrack\n",
311 sh->vtag);
312 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = sh->vtag;
313 } else {
314 /* If it is a shutdown ack OOTB packet, we expect a return
315 shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8) */
316 pr_debug("Setting vtag %x for new conn OOTB\n",
317 sh->vtag);
318 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = sh->vtag;
319 }
320
321 ct->proto.sctp.state = SCTP_CONNTRACK_NONE;
322 }
323
324 return true;
325 }
326
327 static bool sctp_error(struct sk_buff *skb,
328 unsigned int dataoff,
329 const struct nf_hook_state *state)
330 {
331 const struct sctphdr *sh;
332 const char *logmsg;
333
334 if (skb->len < dataoff + sizeof(struct sctphdr)) {
335 logmsg = "nf_ct_sctp: short packet ";
336 goto out_invalid;
337 }
338 if (state->hook == NF_INET_PRE_ROUTING &&
339 state->net->ct.sysctl_checksum &&
340 skb->ip_summed == CHECKSUM_NONE) {
341 if (skb_ensure_writable(skb, dataoff + sizeof(*sh))) {
342 logmsg = "nf_ct_sctp: failed to read header ";
343 goto out_invalid;
344 }
345 sh = (const struct sctphdr *)(skb->data + dataoff);
346 if (sh->checksum != sctp_compute_cksum(skb, dataoff)) {
347 logmsg = "nf_ct_sctp: bad CRC ";
348 goto out_invalid;
349 }
350 skb->ip_summed = CHECKSUM_UNNECESSARY;
351 }
352 return false;
353 out_invalid:
354 nf_l4proto_log_invalid(skb, state->net, state->pf, IPPROTO_SCTP, "%s", logmsg);
355 return true;
356 }
357
358 /* Returns verdict for packet, or -NF_ACCEPT for invalid. */
359 int nf_conntrack_sctp_packet(struct nf_conn *ct,
360 struct sk_buff *skb,
361 unsigned int dataoff,
362 enum ip_conntrack_info ctinfo,
363 const struct nf_hook_state *state)
364 {
365 enum sctp_conntrack new_state, old_state;
366 enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
367 const struct sctphdr *sh;
368 struct sctphdr _sctph;
369 const struct sctp_chunkhdr *sch;
370 struct sctp_chunkhdr _sch;
371 u_int32_t offset, count;
372 unsigned int *timeouts;
373 unsigned long map[256 / sizeof(unsigned long)] = { 0 };
374 bool ignore = false;
375
376 if (sctp_error(skb, dataoff, state))
377 return -NF_ACCEPT;
378
379 sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph);
380 if (sh == NULL)
381 goto out;
382
383 if (do_basic_checks(ct, skb, dataoff, map) != 0)
384 goto out;
385
386 if (!nf_ct_is_confirmed(ct)) {
387 /* If an OOTB packet has any of these chunks discard (Sec 8.4) */
388 if (test_bit(SCTP_CID_ABORT, map) ||
389 test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) ||
390 test_bit(SCTP_CID_COOKIE_ACK, map))
391 return -NF_ACCEPT;
392
393 if (!sctp_new(ct, skb, sh, dataoff))
394 return -NF_ACCEPT;
395 }
396
397 /* Check the verification tag (Sec 8.5) */
398 if (!test_bit(SCTP_CID_INIT, map) &&
399 !test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) &&
400 !test_bit(SCTP_CID_COOKIE_ECHO, map) &&
401 !test_bit(SCTP_CID_ABORT, map) &&
402 !test_bit(SCTP_CID_SHUTDOWN_ACK, map) &&
403 !test_bit(SCTP_CID_HEARTBEAT, map) &&
404 !test_bit(SCTP_CID_HEARTBEAT_ACK, map) &&
405 sh->vtag != ct->proto.sctp.vtag[dir]) {
406 pr_debug("Verification tag check failed\n");
407 goto out;
408 }
409
410 old_state = new_state = SCTP_CONNTRACK_NONE;
411 spin_lock_bh(&ct->lock);
412 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
413 /* Special cases of Verification tag check (Sec 8.5.1) */
414 if (sch->type == SCTP_CID_INIT) {
415 /* Sec 8.5.1 (A) */
416 if (sh->vtag != 0)
417 goto out_unlock;
418 } else if (sch->type == SCTP_CID_ABORT) {
419 /* Sec 8.5.1 (B) */
420 if (sh->vtag != ct->proto.sctp.vtag[dir] &&
421 sh->vtag != ct->proto.sctp.vtag[!dir])
422 goto out_unlock;
423 } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) {
424 /* Sec 8.5.1 (C) */
425 if (sh->vtag != ct->proto.sctp.vtag[dir] &&
426 sh->vtag != ct->proto.sctp.vtag[!dir] &&
427 sch->flags & SCTP_CHUNK_FLAG_T)
428 goto out_unlock;
429 } else if (sch->type == SCTP_CID_COOKIE_ECHO) {
430 /* Sec 8.5.1 (D) */
431 if (sh->vtag != ct->proto.sctp.vtag[dir])
432 goto out_unlock;
433 } else if (sch->type == SCTP_CID_HEARTBEAT) {
434 if (ct->proto.sctp.vtag[dir] == 0) {
435 pr_debug("Setting %d vtag %x for dir %d\n", sch->type, sh->vtag, dir);
436 ct->proto.sctp.vtag[dir] = sh->vtag;
437 } else if (sh->vtag != ct->proto.sctp.vtag[dir]) {
438 if (test_bit(SCTP_CID_DATA, map) || ignore)
439 goto out_unlock;
440
441 ct->proto.sctp.flags |= SCTP_FLAG_HEARTBEAT_VTAG_FAILED;
442 ct->proto.sctp.last_dir = dir;
443 ignore = true;
444 continue;
445 } else if (ct->proto.sctp.flags & SCTP_FLAG_HEARTBEAT_VTAG_FAILED) {
446 ct->proto.sctp.flags &= ~SCTP_FLAG_HEARTBEAT_VTAG_FAILED;
447 }
448 } else if (sch->type == SCTP_CID_HEARTBEAT_ACK) {
449 if (ct->proto.sctp.vtag[dir] == 0) {
450 pr_debug("Setting vtag %x for dir %d\n",
451 sh->vtag, dir);
452 ct->proto.sctp.vtag[dir] = sh->vtag;
453 } else if (sh->vtag != ct->proto.sctp.vtag[dir]) {
454 if (test_bit(SCTP_CID_DATA, map) || ignore)
455 goto out_unlock;
456
457 if ((ct->proto.sctp.flags & SCTP_FLAG_HEARTBEAT_VTAG_FAILED) == 0 ||
458 ct->proto.sctp.last_dir == dir)
459 goto out_unlock;
460
461 ct->proto.sctp.flags &= ~SCTP_FLAG_HEARTBEAT_VTAG_FAILED;
462 ct->proto.sctp.vtag[dir] = sh->vtag;
463 ct->proto.sctp.vtag[!dir] = 0;
464 } else if (ct->proto.sctp.flags & SCTP_FLAG_HEARTBEAT_VTAG_FAILED) {
465 ct->proto.sctp.flags &= ~SCTP_FLAG_HEARTBEAT_VTAG_FAILED;
466 }
467 }
468
469 old_state = ct->proto.sctp.state;
470 new_state = sctp_new_state(dir, old_state, sch->type);
471
472 /* Invalid */
473 if (new_state == SCTP_CONNTRACK_MAX) {
474 pr_debug("nf_conntrack_sctp: Invalid dir=%i ctype=%u "
475 "conntrack=%u\n",
476 dir, sch->type, old_state);
477 goto out_unlock;
478 }
479
480 /* If it is an INIT or an INIT ACK note down the vtag */
481 if (sch->type == SCTP_CID_INIT ||
482 sch->type == SCTP_CID_INIT_ACK) {
483 struct sctp_inithdr _inithdr, *ih;
484
485 ih = skb_header_pointer(skb, offset + sizeof(_sch),
486 sizeof(_inithdr), &_inithdr);
487 if (ih == NULL)
488 goto out_unlock;
489 pr_debug("Setting vtag %x for dir %d\n",
490 ih->init_tag, !dir);
491 ct->proto.sctp.vtag[!dir] = ih->init_tag;
492 }
493
494 ct->proto.sctp.state = new_state;
495 if (old_state != new_state)
496 nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
497 }
498 spin_unlock_bh(&ct->lock);
499
500 /* allow but do not refresh timeout */
501 if (ignore)
502 return NF_ACCEPT;
503
504 timeouts = nf_ct_timeout_lookup(ct);
505 if (!timeouts)
506 timeouts = nf_sctp_pernet(nf_ct_net(ct))->timeouts;
507
508 nf_ct_refresh_acct(ct, ctinfo, skb, timeouts[new_state]);
509
510 if (old_state == SCTP_CONNTRACK_COOKIE_ECHOED &&
511 dir == IP_CT_DIR_REPLY &&
512 new_state == SCTP_CONNTRACK_ESTABLISHED) {
513 pr_debug("Setting assured bit\n");
514 set_bit(IPS_ASSURED_BIT, &ct->status);
515 nf_conntrack_event_cache(IPCT_ASSURED, ct);
516 }
517
518 return NF_ACCEPT;
519
520 out_unlock:
521 spin_unlock_bh(&ct->lock);
522 out:
523 return -NF_ACCEPT;
524 }
525
526 static bool sctp_can_early_drop(const struct nf_conn *ct)
527 {
528 switch (ct->proto.sctp.state) {
529 case SCTP_CONNTRACK_SHUTDOWN_SENT:
530 case SCTP_CONNTRACK_SHUTDOWN_RECD:
531 case SCTP_CONNTRACK_SHUTDOWN_ACK_SENT:
532 return true;
533 default:
534 break;
535 }
536
537 return false;
538 }
539
540 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
541
542 #include <linux/netfilter/nfnetlink.h>
543 #include <linux/netfilter/nfnetlink_conntrack.h>
544
545 static int sctp_to_nlattr(struct sk_buff *skb, struct nlattr *nla,
546 struct nf_conn *ct, bool destroy)
547 {
548 struct nlattr *nest_parms;
549
550 spin_lock_bh(&ct->lock);
551 nest_parms = nla_nest_start(skb, CTA_PROTOINFO_SCTP);
552 if (!nest_parms)
553 goto nla_put_failure;
554
555 if (nla_put_u8(skb, CTA_PROTOINFO_SCTP_STATE, ct->proto.sctp.state))
556 goto nla_put_failure;
557
558 if (destroy)
559 goto skip_state;
560
561 if (nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_ORIGINAL,
562 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL]) ||
563 nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_REPLY,
564 ct->proto.sctp.vtag[IP_CT_DIR_REPLY]))
565 goto nla_put_failure;
566
567 skip_state:
568 spin_unlock_bh(&ct->lock);
569 nla_nest_end(skb, nest_parms);
570
571 return 0;
572
573 nla_put_failure:
574 spin_unlock_bh(&ct->lock);
575 return -1;
576 }
577
578 static const struct nla_policy sctp_nla_policy[CTA_PROTOINFO_SCTP_MAX+1] = {
579 [CTA_PROTOINFO_SCTP_STATE] = { .type = NLA_U8 },
580 [CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] = { .type = NLA_U32 },
581 [CTA_PROTOINFO_SCTP_VTAG_REPLY] = { .type = NLA_U32 },
582 };
583
584 #define SCTP_NLATTR_SIZE ( \
585 NLA_ALIGN(NLA_HDRLEN + 1) + \
586 NLA_ALIGN(NLA_HDRLEN + 4) + \
587 NLA_ALIGN(NLA_HDRLEN + 4))
588
589 static int nlattr_to_sctp(struct nlattr *cda[], struct nf_conn *ct)
590 {
591 struct nlattr *attr = cda[CTA_PROTOINFO_SCTP];
592 struct nlattr *tb[CTA_PROTOINFO_SCTP_MAX+1];
593 int err;
594
595 /* updates may not contain the internal protocol info, skip parsing */
596 if (!attr)
597 return 0;
598
599 err = nla_parse_nested_deprecated(tb, CTA_PROTOINFO_SCTP_MAX, attr,
600 sctp_nla_policy, NULL);
601 if (err < 0)
602 return err;
603
604 if (!tb[CTA_PROTOINFO_SCTP_STATE] ||
605 !tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] ||
606 !tb[CTA_PROTOINFO_SCTP_VTAG_REPLY])
607 return -EINVAL;
608
609 spin_lock_bh(&ct->lock);
610 ct->proto.sctp.state = nla_get_u8(tb[CTA_PROTOINFO_SCTP_STATE]);
611 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] =
612 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL]);
613 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] =
614 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]);
615 spin_unlock_bh(&ct->lock);
616
617 return 0;
618 }
619 #endif
620
621 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
622
623 #include <linux/netfilter/nfnetlink.h>
624 #include <linux/netfilter/nfnetlink_cttimeout.h>
625
626 static int sctp_timeout_nlattr_to_obj(struct nlattr *tb[],
627 struct net *net, void *data)
628 {
629 unsigned int *timeouts = data;
630 struct nf_sctp_net *sn = nf_sctp_pernet(net);
631 int i;
632
633 if (!timeouts)
634 timeouts = sn->timeouts;
635
636 /* set default SCTP timeouts. */
637 for (i=0; i<SCTP_CONNTRACK_MAX; i++)
638 timeouts[i] = sn->timeouts[i];
639
640 /* there's a 1:1 mapping between attributes and protocol states. */
641 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) {
642 if (tb[i]) {
643 timeouts[i] = ntohl(nla_get_be32(tb[i])) * HZ;
644 }
645 }
646
647 timeouts[CTA_TIMEOUT_SCTP_UNSPEC] = timeouts[CTA_TIMEOUT_SCTP_CLOSED];
648 return 0;
649 }
650
651 static int
652 sctp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
653 {
654 const unsigned int *timeouts = data;
655 int i;
656
657 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) {
658 if (nla_put_be32(skb, i, htonl(timeouts[i] / HZ)))
659 goto nla_put_failure;
660 }
661 return 0;
662
663 nla_put_failure:
664 return -ENOSPC;
665 }
666
667 static const struct nla_policy
668 sctp_timeout_nla_policy[CTA_TIMEOUT_SCTP_MAX+1] = {
669 [CTA_TIMEOUT_SCTP_CLOSED] = { .type = NLA_U32 },
670 [CTA_TIMEOUT_SCTP_COOKIE_WAIT] = { .type = NLA_U32 },
671 [CTA_TIMEOUT_SCTP_COOKIE_ECHOED] = { .type = NLA_U32 },
672 [CTA_TIMEOUT_SCTP_ESTABLISHED] = { .type = NLA_U32 },
673 [CTA_TIMEOUT_SCTP_SHUTDOWN_SENT] = { .type = NLA_U32 },
674 [CTA_TIMEOUT_SCTP_SHUTDOWN_RECD] = { .type = NLA_U32 },
675 [CTA_TIMEOUT_SCTP_SHUTDOWN_ACK_SENT] = { .type = NLA_U32 },
676 [CTA_TIMEOUT_SCTP_HEARTBEAT_SENT] = { .type = NLA_U32 },
677 [CTA_TIMEOUT_SCTP_HEARTBEAT_ACKED] = { .type = NLA_U32 },
678 };
679 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
680
681 void nf_conntrack_sctp_init_net(struct net *net)
682 {
683 struct nf_sctp_net *sn = nf_sctp_pernet(net);
684 int i;
685
686 for (i = 0; i < SCTP_CONNTRACK_MAX; i++)
687 sn->timeouts[i] = sctp_timeouts[i];
688
689 /* timeouts[0] is unused, init it so ->timeouts[0] contains
690 * 'new' timeout, like udp or icmp.
691 */
692 sn->timeouts[0] = sctp_timeouts[SCTP_CONNTRACK_CLOSED];
693 }
694
695 const struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp = {
696 .l4proto = IPPROTO_SCTP,
697 #ifdef CONFIG_NF_CONNTRACK_PROCFS
698 .print_conntrack = sctp_print_conntrack,
699 #endif
700 .can_early_drop = sctp_can_early_drop,
701 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
702 .nlattr_size = SCTP_NLATTR_SIZE,
703 .to_nlattr = sctp_to_nlattr,
704 .from_nlattr = nlattr_to_sctp,
705 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
706 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
707 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
708 .nla_policy = nf_ct_port_nla_policy,
709 #endif
710 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
711 .ctnl_timeout = {
712 .nlattr_to_obj = sctp_timeout_nlattr_to_obj,
713 .obj_to_nlattr = sctp_timeout_obj_to_nlattr,
714 .nlattr_max = CTA_TIMEOUT_SCTP_MAX,
715 .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX,
716 .nla_policy = sctp_timeout_nla_policy,
717 },
718 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
719 };
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