1 /*
2 * Connection tracking protocol helper module for SCTP.
3 *
4 * Copyright (c) 2004 Kiran Kumar Immidi <immidi_kiran@yahoo.com>
5 * Copyright (c) 2004-2012 Patrick McHardy <kaber@trash.net>
6 *
7 * SCTP is defined in RFC 2960. References to various sections in this code
8 * are to this RFC.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 */
14
15 #include <linux/types.h>
16 #include <linux/timer.h>
17 #include <linux/netfilter.h>
18 #include <linux/module.h>
19 #include <linux/in.h>
20 #include <linux/ip.h>
21 #include <linux/sctp.h>
22 #include <linux/string.h>
23 #include <linux/seq_file.h>
24 #include <linux/spinlock.h>
25 #include <linux/interrupt.h>
26
27 #include <net/netfilter/nf_conntrack.h>
28 #include <net/netfilter/nf_conntrack_l4proto.h>
29 #include <net/netfilter/nf_conntrack_ecache.h>
30
31 /* FIXME: Examine ipfilter's timeouts and conntrack transitions more
32 closely. They're more complex. --RR
33
34 And so for me for SCTP :D -Kiran */
35
36 static const char *const sctp_conntrack_names[] = {
37 "NONE",
38 "CLOSED",
39 "COOKIE_WAIT",
40 "COOKIE_ECHOED",
41 "ESTABLISHED",
42 "SHUTDOWN_SENT",
43 "SHUTDOWN_RECD",
44 "SHUTDOWN_ACK_SENT",
45 };
46
47 #define SECS * HZ
48 #define MINS * 60 SECS
49 #define HOURS * 60 MINS
50 #define DAYS * 24 HOURS
51
52 static unsigned int sctp_timeouts[SCTP_CONNTRACK_MAX] __read_mostly = {
53 [SCTP_CONNTRACK_CLOSED] = 10 SECS,
54 [SCTP_CONNTRACK_COOKIE_WAIT] = 3 SECS,
55 [SCTP_CONNTRACK_COOKIE_ECHOED] = 3 SECS,
56 [SCTP_CONNTRACK_ESTABLISHED] = 5 DAYS,
57 [SCTP_CONNTRACK_SHUTDOWN_SENT] = 300 SECS / 1000,
58 [SCTP_CONNTRACK_SHUTDOWN_RECD] = 300 SECS / 1000,
59 [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT] = 3 SECS,
60 };
61
62 #define sNO SCTP_CONNTRACK_NONE
63 #define sCL SCTP_CONNTRACK_CLOSED
64 #define sCW SCTP_CONNTRACK_COOKIE_WAIT
65 #define sCE SCTP_CONNTRACK_COOKIE_ECHOED
66 #define sES SCTP_CONNTRACK_ESTABLISHED
67 #define sSS SCTP_CONNTRACK_SHUTDOWN_SENT
68 #define sSR SCTP_CONNTRACK_SHUTDOWN_RECD
69 #define sSA SCTP_CONNTRACK_SHUTDOWN_ACK_SENT
70 #define sIV SCTP_CONNTRACK_MAX
71
72 /*
73 These are the descriptions of the states:
74
75 NOTE: These state names are tantalizingly similar to the states of an
76 SCTP endpoint. But the interpretation of the states is a little different,
77 considering that these are the states of the connection and not of an end
78 point. Please note the subtleties. -Kiran
79
80 NONE - Nothing so far.
81 COOKIE WAIT - We have seen an INIT chunk in the original direction, or also
82 an INIT_ACK chunk in the reply direction.
83 COOKIE ECHOED - We have seen a COOKIE_ECHO chunk in the original direction.
84 ESTABLISHED - We have seen a COOKIE_ACK in the reply direction.
85 SHUTDOWN_SENT - We have seen a SHUTDOWN chunk in the original direction.
86 SHUTDOWN_RECD - We have seen a SHUTDOWN chunk in the reply directoin.
87 SHUTDOWN_ACK_SENT - We have seen a SHUTDOWN_ACK chunk in the direction opposite
88 to that of the SHUTDOWN chunk.
89 CLOSED - We have seen a SHUTDOWN_COMPLETE chunk in the direction of
90 the SHUTDOWN chunk. Connection is closed.
91 */
92
93 /* TODO
94 - I have assumed that the first INIT is in the original direction.
95 This messes things when an INIT comes in the reply direction in CLOSED
96 state.
97 - Check the error type in the reply dir before transitioning from
98 cookie echoed to closed.
99 - Sec 5.2.4 of RFC 2960
100 - Multi Homing support.
101 */
102
103 /* SCTP conntrack state transitions */
104 static const u8 sctp_conntracks[2][9][SCTP_CONNTRACK_MAX] = {
105 {
106 /* ORIGINAL */
107 /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA */
108 /* init */ {sCW, sCW, sCW, sCE, sES, sSS, sSR, sSA},
109 /* init_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA},
110 /* abort */ {sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL},
111 /* shutdown */ {sCL, sCL, sCW, sCE, sSS, sSS, sSR, sSA},
112 /* shutdown_ack */ {sSA, sCL, sCW, sCE, sES, sSA, sSA, sSA},
113 /* error */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* Can't have Stale cookie*/
114 /* cookie_echo */ {sCL, sCL, sCE, sCE, sES, sSS, sSR, sSA},/* 5.2.4 - Big TODO */
115 /* cookie_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* Can't come in orig dir */
116 /* shutdown_comp*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sCL}
117 },
118 {
119 /* REPLY */
120 /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA */
121 /* init */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* INIT in sCL Big TODO */
122 /* init_ack */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA},
123 /* abort */ {sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL},
124 /* shutdown */ {sIV, sCL, sCW, sCE, sSR, sSS, sSR, sSA},
125 /* shutdown_ack */ {sIV, sCL, sCW, sCE, sES, sSA, sSA, sSA},
126 /* error */ {sIV, sCL, sCW, sCL, sES, sSS, sSR, sSA},
127 /* cookie_echo */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* Can't come in reply dir */
128 /* cookie_ack */ {sIV, sCL, sCW, sES, sES, sSS, sSR, sSA},
129 /* shutdown_comp*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sCL}
130 }
131 };
132
133 static int sctp_net_id __read_mostly;
134 struct sctp_net {
135 struct nf_proto_net pn;
136 unsigned int timeouts[SCTP_CONNTRACK_MAX];
137 };
138
139 static inline struct sctp_net *sctp_pernet(struct net *net)
140 {
141 return net_generic(net, sctp_net_id);
142 }
143
144 static bool sctp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff,
145 struct nf_conntrack_tuple *tuple)
146 {
147 const struct sctphdr *hp;
148 struct sctphdr _hdr;
149
150 /* Actually only need first 8 bytes. */
151 hp = skb_header_pointer(skb, dataoff, 8, &_hdr);
152 if (hp == NULL)
153 return false;
154
155 tuple->src.u.sctp.port = hp->source;
156 tuple->dst.u.sctp.port = hp->dest;
157 return true;
158 }
159
160 static bool sctp_invert_tuple(struct nf_conntrack_tuple *tuple,
161 const struct nf_conntrack_tuple *orig)
162 {
163 tuple->src.u.sctp.port = orig->dst.u.sctp.port;
164 tuple->dst.u.sctp.port = orig->src.u.sctp.port;
165 return true;
166 }
167
168 /* Print out the per-protocol part of the tuple. */
169 static int sctp_print_tuple(struct seq_file *s,
170 const struct nf_conntrack_tuple *tuple)
171 {
172 return seq_printf(s, "sport=%hu dport=%hu ",
173 ntohs(tuple->src.u.sctp.port),
174 ntohs(tuple->dst.u.sctp.port));
175 }
176
177 /* Print out the private part of the conntrack. */
178 static int sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
179 {
180 enum sctp_conntrack state;
181
182 spin_lock_bh(&ct->lock);
183 state = ct->proto.sctp.state;
184 spin_unlock_bh(&ct->lock);
185
186 return seq_printf(s, "%s ", sctp_conntrack_names[state]);
187 }
188
189 #define for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) \
190 for ((offset) = (dataoff) + sizeof(sctp_sctphdr_t), (count) = 0; \
191 (offset) < (skb)->len && \
192 ((sch) = skb_header_pointer((skb), (offset), sizeof(_sch), &(_sch))); \
193 (offset) += (ntohs((sch)->length) + 3) & ~3, (count)++)
194
195 /* Some validity checks to make sure the chunks are fine */
196 static int do_basic_checks(struct nf_conn *ct,
197 const struct sk_buff *skb,
198 unsigned int dataoff,
199 unsigned long *map)
200 {
201 u_int32_t offset, count;
202 sctp_chunkhdr_t _sch, *sch;
203 int flag;
204
205 flag = 0;
206
207 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
208 pr_debug("Chunk Num: %d Type: %d\n", count, sch->type);
209
210 if (sch->type == SCTP_CID_INIT ||
211 sch->type == SCTP_CID_INIT_ACK ||
212 sch->type == SCTP_CID_SHUTDOWN_COMPLETE)
213 flag = 1;
214
215 /*
216 * Cookie Ack/Echo chunks not the first OR
217 * Init / Init Ack / Shutdown compl chunks not the only chunks
218 * OR zero-length.
219 */
220 if (((sch->type == SCTP_CID_COOKIE_ACK ||
221 sch->type == SCTP_CID_COOKIE_ECHO ||
222 flag) &&
223 count != 0) || !sch->length) {
224 pr_debug("Basic checks failed\n");
225 return 1;
226 }
227
228 if (map)
229 set_bit(sch->type, map);
230 }
231
232 pr_debug("Basic checks passed\n");
233 return count == 0;
234 }
235
236 static int sctp_new_state(enum ip_conntrack_dir dir,
237 enum sctp_conntrack cur_state,
238 int chunk_type)
239 {
240 int i;
241
242 pr_debug("Chunk type: %d\n", chunk_type);
243
244 switch (chunk_type) {
245 case SCTP_CID_INIT:
246 pr_debug("SCTP_CID_INIT\n");
247 i = 0;
248 break;
249 case SCTP_CID_INIT_ACK:
250 pr_debug("SCTP_CID_INIT_ACK\n");
251 i = 1;
252 break;
253 case SCTP_CID_ABORT:
254 pr_debug("SCTP_CID_ABORT\n");
255 i = 2;
256 break;
257 case SCTP_CID_SHUTDOWN:
258 pr_debug("SCTP_CID_SHUTDOWN\n");
259 i = 3;
260 break;
261 case SCTP_CID_SHUTDOWN_ACK:
262 pr_debug("SCTP_CID_SHUTDOWN_ACK\n");
263 i = 4;
264 break;
265 case SCTP_CID_ERROR:
266 pr_debug("SCTP_CID_ERROR\n");
267 i = 5;
268 break;
269 case SCTP_CID_COOKIE_ECHO:
270 pr_debug("SCTP_CID_COOKIE_ECHO\n");
271 i = 6;
272 break;
273 case SCTP_CID_COOKIE_ACK:
274 pr_debug("SCTP_CID_COOKIE_ACK\n");
275 i = 7;
276 break;
277 case SCTP_CID_SHUTDOWN_COMPLETE:
278 pr_debug("SCTP_CID_SHUTDOWN_COMPLETE\n");
279 i = 8;
280 break;
281 default:
282 /* Other chunks like DATA, SACK, HEARTBEAT and
283 its ACK do not cause a change in state */
284 pr_debug("Unknown chunk type, Will stay in %s\n",
285 sctp_conntrack_names[cur_state]);
286 return cur_state;
287 }
288
289 pr_debug("dir: %d cur_state: %s chunk_type: %d new_state: %s\n",
290 dir, sctp_conntrack_names[cur_state], chunk_type,
291 sctp_conntrack_names[sctp_conntracks[dir][i][cur_state]]);
292
293 return sctp_conntracks[dir][i][cur_state];
294 }
295
296 static unsigned int *sctp_get_timeouts(struct net *net)
297 {
298 return sctp_pernet(net)->timeouts;
299 }
300
301 /* Returns verdict for packet, or -NF_ACCEPT for invalid. */
302 static int sctp_packet(struct nf_conn *ct,
303 const struct sk_buff *skb,
304 unsigned int dataoff,
305 enum ip_conntrack_info ctinfo,
306 u_int8_t pf,
307 unsigned int hooknum,
308 unsigned int *timeouts)
309 {
310 enum sctp_conntrack new_state, old_state;
311 enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
312 const struct sctphdr *sh;
313 struct sctphdr _sctph;
314 const struct sctp_chunkhdr *sch;
315 struct sctp_chunkhdr _sch;
316 u_int32_t offset, count;
317 unsigned long map[256 / sizeof(unsigned long)] = { 0 };
318
319 sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph);
320 if (sh == NULL)
321 goto out;
322
323 if (do_basic_checks(ct, skb, dataoff, map) != 0)
324 goto out;
325
326 /* Check the verification tag (Sec 8.5) */
327 if (!test_bit(SCTP_CID_INIT, map) &&
328 !test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) &&
329 !test_bit(SCTP_CID_COOKIE_ECHO, map) &&
330 !test_bit(SCTP_CID_ABORT, map) &&
331 !test_bit(SCTP_CID_SHUTDOWN_ACK, map) &&
332 sh->vtag != ct->proto.sctp.vtag[dir]) {
333 pr_debug("Verification tag check failed\n");
334 goto out;
335 }
336
337 old_state = new_state = SCTP_CONNTRACK_NONE;
338 spin_lock_bh(&ct->lock);
339 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
340 /* Special cases of Verification tag check (Sec 8.5.1) */
341 if (sch->type == SCTP_CID_INIT) {
342 /* Sec 8.5.1 (A) */
343 if (sh->vtag != 0)
344 goto out_unlock;
345 } else if (sch->type == SCTP_CID_ABORT) {
346 /* Sec 8.5.1 (B) */
347 if (sh->vtag != ct->proto.sctp.vtag[dir] &&
348 sh->vtag != ct->proto.sctp.vtag[!dir])
349 goto out_unlock;
350 } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) {
351 /* Sec 8.5.1 (C) */
352 if (sh->vtag != ct->proto.sctp.vtag[dir] &&
353 sh->vtag != ct->proto.sctp.vtag[!dir] &&
354 sch->flags & SCTP_CHUNK_FLAG_T)
355 goto out_unlock;
356 } else if (sch->type == SCTP_CID_COOKIE_ECHO) {
357 /* Sec 8.5.1 (D) */
358 if (sh->vtag != ct->proto.sctp.vtag[dir])
359 goto out_unlock;
360 }
361
362 old_state = ct->proto.sctp.state;
363 new_state = sctp_new_state(dir, old_state, sch->type);
364
365 /* Invalid */
366 if (new_state == SCTP_CONNTRACK_MAX) {
367 pr_debug("nf_conntrack_sctp: Invalid dir=%i ctype=%u "
368 "conntrack=%u\n",
369 dir, sch->type, old_state);
370 goto out_unlock;
371 }
372
373 /* If it is an INIT or an INIT ACK note down the vtag */
374 if (sch->type == SCTP_CID_INIT ||
375 sch->type == SCTP_CID_INIT_ACK) {
376 sctp_inithdr_t _inithdr, *ih;
377
378 ih = skb_header_pointer(skb, offset + sizeof(sctp_chunkhdr_t),
379 sizeof(_inithdr), &_inithdr);
380 if (ih == NULL)
381 goto out_unlock;
382 pr_debug("Setting vtag %x for dir %d\n",
383 ih->init_tag, !dir);
384 ct->proto.sctp.vtag[!dir] = ih->init_tag;
385 }
386
387 ct->proto.sctp.state = new_state;
388 if (old_state != new_state)
389 nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
390 }
391 spin_unlock_bh(&ct->lock);
392
393 nf_ct_refresh_acct(ct, ctinfo, skb, timeouts[new_state]);
394
395 if (old_state == SCTP_CONNTRACK_COOKIE_ECHOED &&
396 dir == IP_CT_DIR_REPLY &&
397 new_state == SCTP_CONNTRACK_ESTABLISHED) {
398 pr_debug("Setting assured bit\n");
399 set_bit(IPS_ASSURED_BIT, &ct->status);
400 nf_conntrack_event_cache(IPCT_ASSURED, ct);
401 }
402
403 return NF_ACCEPT;
404
405 out_unlock:
406 spin_unlock_bh(&ct->lock);
407 out:
408 return -NF_ACCEPT;
409 }
410
411 /* Called when a new connection for this protocol found. */
412 static bool sctp_new(struct nf_conn *ct, const struct sk_buff *skb,
413 unsigned int dataoff, unsigned int *timeouts)
414 {
415 enum sctp_conntrack new_state;
416 const struct sctphdr *sh;
417 struct sctphdr _sctph;
418 const struct sctp_chunkhdr *sch;
419 struct sctp_chunkhdr _sch;
420 u_int32_t offset, count;
421 unsigned long map[256 / sizeof(unsigned long)] = { 0 };
422
423 sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph);
424 if (sh == NULL)
425 return false;
426
427 if (do_basic_checks(ct, skb, dataoff, map) != 0)
428 return false;
429
430 /* If an OOTB packet has any of these chunks discard (Sec 8.4) */
431 if (test_bit(SCTP_CID_ABORT, map) ||
432 test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) ||
433 test_bit(SCTP_CID_COOKIE_ACK, map))
434 return false;
435
436 memset(&ct->proto.sctp, 0, sizeof(ct->proto.sctp));
437 new_state = SCTP_CONNTRACK_MAX;
438 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
439 /* Don't need lock here: this conntrack not in circulation yet */
440 new_state = sctp_new_state(IP_CT_DIR_ORIGINAL,
441 SCTP_CONNTRACK_NONE, sch->type);
442
443 /* Invalid: delete conntrack */
444 if (new_state == SCTP_CONNTRACK_NONE ||
445 new_state == SCTP_CONNTRACK_MAX) {
446 pr_debug("nf_conntrack_sctp: invalid new deleting.\n");
447 return false;
448 }
449
450 /* Copy the vtag into the state info */
451 if (sch->type == SCTP_CID_INIT) {
452 if (sh->vtag == 0) {
453 sctp_inithdr_t _inithdr, *ih;
454
455 ih = skb_header_pointer(skb, offset + sizeof(sctp_chunkhdr_t),
456 sizeof(_inithdr), &_inithdr);
457 if (ih == NULL)
458 return false;
459
460 pr_debug("Setting vtag %x for new conn\n",
461 ih->init_tag);
462
463 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] =
464 ih->init_tag;
465 } else {
466 /* Sec 8.5.1 (A) */
467 return false;
468 }
469 }
470 /* If it is a shutdown ack OOTB packet, we expect a return
471 shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8) */
472 else {
473 pr_debug("Setting vtag %x for new conn OOTB\n",
474 sh->vtag);
475 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = sh->vtag;
476 }
477
478 ct->proto.sctp.state = new_state;
479 }
480
481 return true;
482 }
483
484 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
485
486 #include <linux/netfilter/nfnetlink.h>
487 #include <linux/netfilter/nfnetlink_conntrack.h>
488
489 static int sctp_to_nlattr(struct sk_buff *skb, struct nlattr *nla,
490 struct nf_conn *ct)
491 {
492 struct nlattr *nest_parms;
493
494 spin_lock_bh(&ct->lock);
495 nest_parms = nla_nest_start(skb, CTA_PROTOINFO_SCTP | NLA_F_NESTED);
496 if (!nest_parms)
497 goto nla_put_failure;
498
499 if (nla_put_u8(skb, CTA_PROTOINFO_SCTP_STATE, ct->proto.sctp.state) ||
500 nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_ORIGINAL,
501 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL]) ||
502 nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_REPLY,
503 ct->proto.sctp.vtag[IP_CT_DIR_REPLY]))
504 goto nla_put_failure;
505
506 spin_unlock_bh(&ct->lock);
507
508 nla_nest_end(skb, nest_parms);
509
510 return 0;
511
512 nla_put_failure:
513 spin_unlock_bh(&ct->lock);
514 return -1;
515 }
516
517 static const struct nla_policy sctp_nla_policy[CTA_PROTOINFO_SCTP_MAX+1] = {
518 [CTA_PROTOINFO_SCTP_STATE] = { .type = NLA_U8 },
519 [CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] = { .type = NLA_U32 },
520 [CTA_PROTOINFO_SCTP_VTAG_REPLY] = { .type = NLA_U32 },
521 };
522
523 static int nlattr_to_sctp(struct nlattr *cda[], struct nf_conn *ct)
524 {
525 struct nlattr *attr = cda[CTA_PROTOINFO_SCTP];
526 struct nlattr *tb[CTA_PROTOINFO_SCTP_MAX+1];
527 int err;
528
529 /* updates may not contain the internal protocol info, skip parsing */
530 if (!attr)
531 return 0;
532
533 err = nla_parse_nested(tb,
534 CTA_PROTOINFO_SCTP_MAX,
535 attr,
536 sctp_nla_policy);
537 if (err < 0)
538 return err;
539
540 if (!tb[CTA_PROTOINFO_SCTP_STATE] ||
541 !tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] ||
542 !tb[CTA_PROTOINFO_SCTP_VTAG_REPLY])
543 return -EINVAL;
544
545 spin_lock_bh(&ct->lock);
546 ct->proto.sctp.state = nla_get_u8(tb[CTA_PROTOINFO_SCTP_STATE]);
547 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] =
548 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL]);
549 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] =
550 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]);
551 spin_unlock_bh(&ct->lock);
552
553 return 0;
554 }
555
556 static int sctp_nlattr_size(void)
557 {
558 return nla_total_size(0) /* CTA_PROTOINFO_SCTP */
559 + nla_policy_len(sctp_nla_policy, CTA_PROTOINFO_SCTP_MAX + 1);
560 }
561 #endif
562
563 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
564
565 #include <linux/netfilter/nfnetlink.h>
566 #include <linux/netfilter/nfnetlink_cttimeout.h>
567
568 static int sctp_timeout_nlattr_to_obj(struct nlattr *tb[],
569 struct net *net, void *data)
570 {
571 unsigned int *timeouts = data;
572 struct sctp_net *sn = sctp_pernet(net);
573 int i;
574
575 /* set default SCTP timeouts. */
576 for (i=0; i<SCTP_CONNTRACK_MAX; i++)
577 timeouts[i] = sn->timeouts[i];
578
579 /* there's a 1:1 mapping between attributes and protocol states. */
580 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) {
581 if (tb[i]) {
582 timeouts[i] = ntohl(nla_get_be32(tb[i])) * HZ;
583 }
584 }
585 return 0;
586 }
587
588 static int
589 sctp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
590 {
591 const unsigned int *timeouts = data;
592 int i;
593
594 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) {
595 if (nla_put_be32(skb, i, htonl(timeouts[i] / HZ)))
596 goto nla_put_failure;
597 }
598 return 0;
599
600 nla_put_failure:
601 return -ENOSPC;
602 }
603
604 static const struct nla_policy
605 sctp_timeout_nla_policy[CTA_TIMEOUT_SCTP_MAX+1] = {
606 [CTA_TIMEOUT_SCTP_CLOSED] = { .type = NLA_U32 },
607 [CTA_TIMEOUT_SCTP_COOKIE_WAIT] = { .type = NLA_U32 },
608 [CTA_TIMEOUT_SCTP_COOKIE_ECHOED] = { .type = NLA_U32 },
609 [CTA_TIMEOUT_SCTP_ESTABLISHED] = { .type = NLA_U32 },
610 [CTA_TIMEOUT_SCTP_SHUTDOWN_SENT] = { .type = NLA_U32 },
611 [CTA_TIMEOUT_SCTP_SHUTDOWN_RECD] = { .type = NLA_U32 },
612 [CTA_TIMEOUT_SCTP_SHUTDOWN_ACK_SENT] = { .type = NLA_U32 },
613 };
614 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
615
616
617 #ifdef CONFIG_SYSCTL
618 static struct ctl_table sctp_sysctl_table[] = {
619 {
620 .procname = "nf_conntrack_sctp_timeout_closed",
621 .maxlen = sizeof(unsigned int),
622 .mode = 0644,
623 .proc_handler = proc_dointvec_jiffies,
624 },
625 {
626 .procname = "nf_conntrack_sctp_timeout_cookie_wait",
627 .maxlen = sizeof(unsigned int),
628 .mode = 0644,
629 .proc_handler = proc_dointvec_jiffies,
630 },
631 {
632 .procname = "nf_conntrack_sctp_timeout_cookie_echoed",
633 .maxlen = sizeof(unsigned int),
634 .mode = 0644,
635 .proc_handler = proc_dointvec_jiffies,
636 },
637 {
638 .procname = "nf_conntrack_sctp_timeout_established",
639 .maxlen = sizeof(unsigned int),
640 .mode = 0644,
641 .proc_handler = proc_dointvec_jiffies,
642 },
643 {
644 .procname = "nf_conntrack_sctp_timeout_shutdown_sent",
645 .maxlen = sizeof(unsigned int),
646 .mode = 0644,
647 .proc_handler = proc_dointvec_jiffies,
648 },
649 {
650 .procname = "nf_conntrack_sctp_timeout_shutdown_recd",
651 .maxlen = sizeof(unsigned int),
652 .mode = 0644,
653 .proc_handler = proc_dointvec_jiffies,
654 },
655 {
656 .procname = "nf_conntrack_sctp_timeout_shutdown_ack_sent",
657 .maxlen = sizeof(unsigned int),
658 .mode = 0644,
659 .proc_handler = proc_dointvec_jiffies,
660 },
661 { }
662 };
663
664 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
665 static struct ctl_table sctp_compat_sysctl_table[] = {
666 {
667 .procname = "ip_conntrack_sctp_timeout_closed",
668 .maxlen = sizeof(unsigned int),
669 .mode = 0644,
670 .proc_handler = proc_dointvec_jiffies,
671 },
672 {
673 .procname = "ip_conntrack_sctp_timeout_cookie_wait",
674 .maxlen = sizeof(unsigned int),
675 .mode = 0644,
676 .proc_handler = proc_dointvec_jiffies,
677 },
678 {
679 .procname = "ip_conntrack_sctp_timeout_cookie_echoed",
680 .maxlen = sizeof(unsigned int),
681 .mode = 0644,
682 .proc_handler = proc_dointvec_jiffies,
683 },
684 {
685 .procname = "ip_conntrack_sctp_timeout_established",
686 .maxlen = sizeof(unsigned int),
687 .mode = 0644,
688 .proc_handler = proc_dointvec_jiffies,
689 },
690 {
691 .procname = "ip_conntrack_sctp_timeout_shutdown_sent",
692 .maxlen = sizeof(unsigned int),
693 .mode = 0644,
694 .proc_handler = proc_dointvec_jiffies,
695 },
696 {
697 .procname = "ip_conntrack_sctp_timeout_shutdown_recd",
698 .maxlen = sizeof(unsigned int),
699 .mode = 0644,
700 .proc_handler = proc_dointvec_jiffies,
701 },
702 {
703 .procname = "ip_conntrack_sctp_timeout_shutdown_ack_sent",
704 .maxlen = sizeof(unsigned int),
705 .mode = 0644,
706 .proc_handler = proc_dointvec_jiffies,
707 },
708 { }
709 };
710 #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
711 #endif
712
713 static int sctp_kmemdup_sysctl_table(struct nf_proto_net *pn,
714 struct sctp_net *sn)
715 {
716 #ifdef CONFIG_SYSCTL
717 if (pn->ctl_table)
718 return 0;
719
720 pn->ctl_table = kmemdup(sctp_sysctl_table,
721 sizeof(sctp_sysctl_table),
722 GFP_KERNEL);
723 if (!pn->ctl_table)
724 return -ENOMEM;
725
726 pn->ctl_table[0].data = &sn->timeouts[SCTP_CONNTRACK_CLOSED];
727 pn->ctl_table[1].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_WAIT];
728 pn->ctl_table[2].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_ECHOED];
729 pn->ctl_table[3].data = &sn->timeouts[SCTP_CONNTRACK_ESTABLISHED];
730 pn->ctl_table[4].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT];
731 pn->ctl_table[5].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD];
732 pn->ctl_table[6].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT];
733 #endif
734 return 0;
735 }
736
737 static int sctp_kmemdup_compat_sysctl_table(struct nf_proto_net *pn,
738 struct sctp_net *sn)
739 {
740 #ifdef CONFIG_SYSCTL
741 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
742 pn->ctl_compat_table = kmemdup(sctp_compat_sysctl_table,
743 sizeof(sctp_compat_sysctl_table),
744 GFP_KERNEL);
745 if (!pn->ctl_compat_table)
746 return -ENOMEM;
747
748 pn->ctl_compat_table[0].data = &sn->timeouts[SCTP_CONNTRACK_CLOSED];
749 pn->ctl_compat_table[1].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_WAIT];
750 pn->ctl_compat_table[2].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_ECHOED];
751 pn->ctl_compat_table[3].data = &sn->timeouts[SCTP_CONNTRACK_ESTABLISHED];
752 pn->ctl_compat_table[4].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT];
753 pn->ctl_compat_table[5].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD];
754 pn->ctl_compat_table[6].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT];
755 #endif
756 #endif
757 return 0;
758 }
759
760 static int sctp_init_net(struct net *net, u_int16_t proto)
761 {
762 int ret;
763 struct sctp_net *sn = sctp_pernet(net);
764 struct nf_proto_net *pn = &sn->pn;
765
766 if (!pn->users) {
767 int i;
768
769 for (i = 0; i < SCTP_CONNTRACK_MAX; i++)
770 sn->timeouts[i] = sctp_timeouts[i];
771 }
772
773 if (proto == AF_INET) {
774 ret = sctp_kmemdup_compat_sysctl_table(pn, sn);
775 if (ret < 0)
776 return ret;
777
778 ret = sctp_kmemdup_sysctl_table(pn, sn);
779 if (ret < 0)
780 nf_ct_kfree_compat_sysctl_table(pn);
781 } else
782 ret = sctp_kmemdup_sysctl_table(pn, sn);
783
784 return ret;
785 }
786
787 static struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp4 __read_mostly = {
788 .l3proto = PF_INET,
789 .l4proto = IPPROTO_SCTP,
790 .name = "sctp",
791 .pkt_to_tuple = sctp_pkt_to_tuple,
792 .invert_tuple = sctp_invert_tuple,
793 .print_tuple = sctp_print_tuple,
794 .print_conntrack = sctp_print_conntrack,
795 .packet = sctp_packet,
796 .get_timeouts = sctp_get_timeouts,
797 .new = sctp_new,
798 .me = THIS_MODULE,
799 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
800 .to_nlattr = sctp_to_nlattr,
801 .nlattr_size = sctp_nlattr_size,
802 .from_nlattr = nlattr_to_sctp,
803 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
804 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
805 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
806 .nla_policy = nf_ct_port_nla_policy,
807 #endif
808 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
809 .ctnl_timeout = {
810 .nlattr_to_obj = sctp_timeout_nlattr_to_obj,
811 .obj_to_nlattr = sctp_timeout_obj_to_nlattr,
812 .nlattr_max = CTA_TIMEOUT_SCTP_MAX,
813 .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX,
814 .nla_policy = sctp_timeout_nla_policy,
815 },
816 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
817 .net_id = &sctp_net_id,
818 .init_net = sctp_init_net,
819 };
820
821 static struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp6 __read_mostly = {
822 .l3proto = PF_INET6,
823 .l4proto = IPPROTO_SCTP,
824 .name = "sctp",
825 .pkt_to_tuple = sctp_pkt_to_tuple,
826 .invert_tuple = sctp_invert_tuple,
827 .print_tuple = sctp_print_tuple,
828 .print_conntrack = sctp_print_conntrack,
829 .packet = sctp_packet,
830 .get_timeouts = sctp_get_timeouts,
831 .new = sctp_new,
832 .me = THIS_MODULE,
833 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
834 .to_nlattr = sctp_to_nlattr,
835 .nlattr_size = sctp_nlattr_size,
836 .from_nlattr = nlattr_to_sctp,
837 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
838 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
839 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
840 .nla_policy = nf_ct_port_nla_policy,
841 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
842 .ctnl_timeout = {
843 .nlattr_to_obj = sctp_timeout_nlattr_to_obj,
844 .obj_to_nlattr = sctp_timeout_obj_to_nlattr,
845 .nlattr_max = CTA_TIMEOUT_SCTP_MAX,
846 .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX,
847 .nla_policy = sctp_timeout_nla_policy,
848 },
849 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
850 #endif
851 .net_id = &sctp_net_id,
852 .init_net = sctp_init_net,
853 };
854
855 static int sctp_net_init(struct net *net)
856 {
857 int ret = 0;
858
859 ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_sctp4);
860 if (ret < 0) {
861 pr_err("nf_conntrack_sctp4: pernet registration failed.\n");
862 goto out;
863 }
864 ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_sctp6);
865 if (ret < 0) {
866 pr_err("nf_conntrack_sctp6: pernet registration failed.\n");
867 goto cleanup_sctp4;
868 }
869 return 0;
870
871 cleanup_sctp4:
872 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_sctp4);
873 out:
874 return ret;
875 }
876
877 static void sctp_net_exit(struct net *net)
878 {
879 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_sctp6);
880 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_sctp4);
881 }
882
883 static struct pernet_operations sctp_net_ops = {
884 .init = sctp_net_init,
885 .exit = sctp_net_exit,
886 .id = &sctp_net_id,
887 .size = sizeof(struct sctp_net),
888 };
889
890 static int __init nf_conntrack_proto_sctp_init(void)
891 {
892 int ret;
893
894 ret = register_pernet_subsys(&sctp_net_ops);
895 if (ret < 0)
896 goto out_pernet;
897
898 ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_sctp4);
899 if (ret < 0)
900 goto out_sctp4;
901
902 ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_sctp6);
903 if (ret < 0)
904 goto out_sctp6;
905
906 return 0;
907 out_sctp6:
908 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_sctp4);
909 out_sctp4:
910 unregister_pernet_subsys(&sctp_net_ops);
911 out_pernet:
912 return ret;
913 }
914
915 static void __exit nf_conntrack_proto_sctp_fini(void)
916 {
917 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_sctp6);
918 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_sctp4);
919 unregister_pernet_subsys(&sctp_net_ops);
920 }
921
922 module_init(nf_conntrack_proto_sctp_init);
923 module_exit(nf_conntrack_proto_sctp_fini);
924
925 MODULE_LICENSE("GPL");
926 MODULE_AUTHOR("Kiran Kumar Immidi");
927 MODULE_DESCRIPTION("Netfilter connection tracking protocol helper for SCTP");
928 MODULE_ALIAS("ip_conntrack_proto_sctp");
929
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