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netfilter: add protocol independent NAT core
[deliverable/linux.git] / net / netfilter / nf_conntrack_proto_tcp.c
1 /* (C) 1999-2001 Paul `Rusty' Russell
2 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8
9 #include <linux/types.h>
10 #include <linux/timer.h>
11 #include <linux/module.h>
12 #include <linux/in.h>
13 #include <linux/tcp.h>
14 #include <linux/spinlock.h>
15 #include <linux/skbuff.h>
16 #include <linux/ipv6.h>
17 #include <net/ip6_checksum.h>
18 #include <asm/unaligned.h>
19
20 #include <net/tcp.h>
21
22 #include <linux/netfilter.h>
23 #include <linux/netfilter_ipv4.h>
24 #include <linux/netfilter_ipv6.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_log.h>
29 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
30 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
31
32 /* "Be conservative in what you do,
33 be liberal in what you accept from others."
34 If it's non-zero, we mark only out of window RST segments as INVALID. */
35 static int nf_ct_tcp_be_liberal __read_mostly = 0;
36
37 /* If it is set to zero, we disable picking up already established
38 connections. */
39 static int nf_ct_tcp_loose __read_mostly = 1;
40
41 /* Max number of the retransmitted packets without receiving an (acceptable)
42 ACK from the destination. If this number is reached, a shorter timer
43 will be started. */
44 static int nf_ct_tcp_max_retrans __read_mostly = 3;
45
46 /* FIXME: Examine ipfilter's timeouts and conntrack transitions more
47 closely. They're more complex. --RR */
48
49 static const char *const tcp_conntrack_names[] = {
50 "NONE",
51 "SYN_SENT",
52 "SYN_RECV",
53 "ESTABLISHED",
54 "FIN_WAIT",
55 "CLOSE_WAIT",
56 "LAST_ACK",
57 "TIME_WAIT",
58 "CLOSE",
59 "SYN_SENT2",
60 };
61
62 #define SECS * HZ
63 #define MINS * 60 SECS
64 #define HOURS * 60 MINS
65 #define DAYS * 24 HOURS
66
67 static unsigned int tcp_timeouts[TCP_CONNTRACK_TIMEOUT_MAX] __read_mostly = {
68 [TCP_CONNTRACK_SYN_SENT] = 2 MINS,
69 [TCP_CONNTRACK_SYN_RECV] = 60 SECS,
70 [TCP_CONNTRACK_ESTABLISHED] = 5 DAYS,
71 [TCP_CONNTRACK_FIN_WAIT] = 2 MINS,
72 [TCP_CONNTRACK_CLOSE_WAIT] = 60 SECS,
73 [TCP_CONNTRACK_LAST_ACK] = 30 SECS,
74 [TCP_CONNTRACK_TIME_WAIT] = 2 MINS,
75 [TCP_CONNTRACK_CLOSE] = 10 SECS,
76 [TCP_CONNTRACK_SYN_SENT2] = 2 MINS,
77 /* RFC1122 says the R2 limit should be at least 100 seconds.
78 Linux uses 15 packets as limit, which corresponds
79 to ~13-30min depending on RTO. */
80 [TCP_CONNTRACK_RETRANS] = 5 MINS,
81 [TCP_CONNTRACK_UNACK] = 5 MINS,
82 };
83
84 #define sNO TCP_CONNTRACK_NONE
85 #define sSS TCP_CONNTRACK_SYN_SENT
86 #define sSR TCP_CONNTRACK_SYN_RECV
87 #define sES TCP_CONNTRACK_ESTABLISHED
88 #define sFW TCP_CONNTRACK_FIN_WAIT
89 #define sCW TCP_CONNTRACK_CLOSE_WAIT
90 #define sLA TCP_CONNTRACK_LAST_ACK
91 #define sTW TCP_CONNTRACK_TIME_WAIT
92 #define sCL TCP_CONNTRACK_CLOSE
93 #define sS2 TCP_CONNTRACK_SYN_SENT2
94 #define sIV TCP_CONNTRACK_MAX
95 #define sIG TCP_CONNTRACK_IGNORE
96
97 /* What TCP flags are set from RST/SYN/FIN/ACK. */
98 enum tcp_bit_set {
99 TCP_SYN_SET,
100 TCP_SYNACK_SET,
101 TCP_FIN_SET,
102 TCP_ACK_SET,
103 TCP_RST_SET,
104 TCP_NONE_SET,
105 };
106
107 /*
108 * The TCP state transition table needs a few words...
109 *
110 * We are the man in the middle. All the packets go through us
111 * but might get lost in transit to the destination.
112 * It is assumed that the destinations can't receive segments
113 * we haven't seen.
114 *
115 * The checked segment is in window, but our windows are *not*
116 * equivalent with the ones of the sender/receiver. We always
117 * try to guess the state of the current sender.
118 *
119 * The meaning of the states are:
120 *
121 * NONE: initial state
122 * SYN_SENT: SYN-only packet seen
123 * SYN_SENT2: SYN-only packet seen from reply dir, simultaneous open
124 * SYN_RECV: SYN-ACK packet seen
125 * ESTABLISHED: ACK packet seen
126 * FIN_WAIT: FIN packet seen
127 * CLOSE_WAIT: ACK seen (after FIN)
128 * LAST_ACK: FIN seen (after FIN)
129 * TIME_WAIT: last ACK seen
130 * CLOSE: closed connection (RST)
131 *
132 * Packets marked as IGNORED (sIG):
133 * if they may be either invalid or valid
134 * and the receiver may send back a connection
135 * closing RST or a SYN/ACK.
136 *
137 * Packets marked as INVALID (sIV):
138 * if we regard them as truly invalid packets
139 */
140 static const u8 tcp_conntracks[2][6][TCP_CONNTRACK_MAX] = {
141 {
142 /* ORIGINAL */
143 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
144 /*syn*/ { sSS, sSS, sIG, sIG, sIG, sIG, sIG, sSS, sSS, sS2 },
145 /*
146 * sNO -> sSS Initialize a new connection
147 * sSS -> sSS Retransmitted SYN
148 * sS2 -> sS2 Late retransmitted SYN
149 * sSR -> sIG
150 * sES -> sIG Error: SYNs in window outside the SYN_SENT state
151 * are errors. Receiver will reply with RST
152 * and close the connection.
153 * Or we are not in sync and hold a dead connection.
154 * sFW -> sIG
155 * sCW -> sIG
156 * sLA -> sIG
157 * sTW -> sSS Reopened connection (RFC 1122).
158 * sCL -> sSS
159 */
160 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
161 /*synack*/ { sIV, sIV, sIG, sIG, sIG, sIG, sIG, sIG, sIG, sSR },
162 /*
163 * sNO -> sIV Too late and no reason to do anything
164 * sSS -> sIV Client can't send SYN and then SYN/ACK
165 * sS2 -> sSR SYN/ACK sent to SYN2 in simultaneous open
166 * sSR -> sIG
167 * sES -> sIG Error: SYNs in window outside the SYN_SENT state
168 * are errors. Receiver will reply with RST
169 * and close the connection.
170 * Or we are not in sync and hold a dead connection.
171 * sFW -> sIG
172 * sCW -> sIG
173 * sLA -> sIG
174 * sTW -> sIG
175 * sCL -> sIG
176 */
177 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
178 /*fin*/ { sIV, sIV, sFW, sFW, sLA, sLA, sLA, sTW, sCL, sIV },
179 /*
180 * sNO -> sIV Too late and no reason to do anything...
181 * sSS -> sIV Client migth not send FIN in this state:
182 * we enforce waiting for a SYN/ACK reply first.
183 * sS2 -> sIV
184 * sSR -> sFW Close started.
185 * sES -> sFW
186 * sFW -> sLA FIN seen in both directions, waiting for
187 * the last ACK.
188 * Migth be a retransmitted FIN as well...
189 * sCW -> sLA
190 * sLA -> sLA Retransmitted FIN. Remain in the same state.
191 * sTW -> sTW
192 * sCL -> sCL
193 */
194 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
195 /*ack*/ { sES, sIV, sES, sES, sCW, sCW, sTW, sTW, sCL, sIV },
196 /*
197 * sNO -> sES Assumed.
198 * sSS -> sIV ACK is invalid: we haven't seen a SYN/ACK yet.
199 * sS2 -> sIV
200 * sSR -> sES Established state is reached.
201 * sES -> sES :-)
202 * sFW -> sCW Normal close request answered by ACK.
203 * sCW -> sCW
204 * sLA -> sTW Last ACK detected.
205 * sTW -> sTW Retransmitted last ACK. Remain in the same state.
206 * sCL -> sCL
207 */
208 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
209 /*rst*/ { sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL },
210 /*none*/ { sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV }
211 },
212 {
213 /* REPLY */
214 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
215 /*syn*/ { sIV, sS2, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sS2 },
216 /*
217 * sNO -> sIV Never reached.
218 * sSS -> sS2 Simultaneous open
219 * sS2 -> sS2 Retransmitted simultaneous SYN
220 * sSR -> sIV Invalid SYN packets sent by the server
221 * sES -> sIV
222 * sFW -> sIV
223 * sCW -> sIV
224 * sLA -> sIV
225 * sTW -> sIV Reopened connection, but server may not do it.
226 * sCL -> sIV
227 */
228 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
229 /*synack*/ { sIV, sSR, sIG, sIG, sIG, sIG, sIG, sIG, sIG, sSR },
230 /*
231 * sSS -> sSR Standard open.
232 * sS2 -> sSR Simultaneous open
233 * sSR -> sIG Retransmitted SYN/ACK, ignore it.
234 * sES -> sIG Late retransmitted SYN/ACK?
235 * sFW -> sIG Might be SYN/ACK answering ignored SYN
236 * sCW -> sIG
237 * sLA -> sIG
238 * sTW -> sIG
239 * sCL -> sIG
240 */
241 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
242 /*fin*/ { sIV, sIV, sFW, sFW, sLA, sLA, sLA, sTW, sCL, sIV },
243 /*
244 * sSS -> sIV Server might not send FIN in this state.
245 * sS2 -> sIV
246 * sSR -> sFW Close started.
247 * sES -> sFW
248 * sFW -> sLA FIN seen in both directions.
249 * sCW -> sLA
250 * sLA -> sLA Retransmitted FIN.
251 * sTW -> sTW
252 * sCL -> sCL
253 */
254 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
255 /*ack*/ { sIV, sIG, sSR, sES, sCW, sCW, sTW, sTW, sCL, sIG },
256 /*
257 * sSS -> sIG Might be a half-open connection.
258 * sS2 -> sIG
259 * sSR -> sSR Might answer late resent SYN.
260 * sES -> sES :-)
261 * sFW -> sCW Normal close request answered by ACK.
262 * sCW -> sCW
263 * sLA -> sTW Last ACK detected.
264 * sTW -> sTW Retransmitted last ACK.
265 * sCL -> sCL
266 */
267 /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
268 /*rst*/ { sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL },
269 /*none*/ { sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV }
270 }
271 };
272
273 static inline struct nf_tcp_net *tcp_pernet(struct net *net)
274 {
275 return &net->ct.nf_ct_proto.tcp;
276 }
277
278 static bool tcp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff,
279 struct nf_conntrack_tuple *tuple)
280 {
281 const struct tcphdr *hp;
282 struct tcphdr _hdr;
283
284 /* Actually only need first 8 bytes. */
285 hp = skb_header_pointer(skb, dataoff, 8, &_hdr);
286 if (hp == NULL)
287 return false;
288
289 tuple->src.u.tcp.port = hp->source;
290 tuple->dst.u.tcp.port = hp->dest;
291
292 return true;
293 }
294
295 static bool tcp_invert_tuple(struct nf_conntrack_tuple *tuple,
296 const struct nf_conntrack_tuple *orig)
297 {
298 tuple->src.u.tcp.port = orig->dst.u.tcp.port;
299 tuple->dst.u.tcp.port = orig->src.u.tcp.port;
300 return true;
301 }
302
303 /* Print out the per-protocol part of the tuple. */
304 static int tcp_print_tuple(struct seq_file *s,
305 const struct nf_conntrack_tuple *tuple)
306 {
307 return seq_printf(s, "sport=%hu dport=%hu ",
308 ntohs(tuple->src.u.tcp.port),
309 ntohs(tuple->dst.u.tcp.port));
310 }
311
312 /* Print out the private part of the conntrack. */
313 static int tcp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
314 {
315 enum tcp_conntrack state;
316
317 spin_lock_bh(&ct->lock);
318 state = ct->proto.tcp.state;
319 spin_unlock_bh(&ct->lock);
320
321 return seq_printf(s, "%s ", tcp_conntrack_names[state]);
322 }
323
324 static unsigned int get_conntrack_index(const struct tcphdr *tcph)
325 {
326 if (tcph->rst) return TCP_RST_SET;
327 else if (tcph->syn) return (tcph->ack ? TCP_SYNACK_SET : TCP_SYN_SET);
328 else if (tcph->fin) return TCP_FIN_SET;
329 else if (tcph->ack) return TCP_ACK_SET;
330 else return TCP_NONE_SET;
331 }
332
333 /* TCP connection tracking based on 'Real Stateful TCP Packet Filtering
334 in IP Filter' by Guido van Rooij.
335
336 http://www.sane.nl/events/sane2000/papers.html
337 http://www.darkart.com/mirrors/www.obfuscation.org/ipf/
338
339 The boundaries and the conditions are changed according to RFC793:
340 the packet must intersect the window (i.e. segments may be
341 after the right or before the left edge) and thus receivers may ACK
342 segments after the right edge of the window.
343
344 td_maxend = max(sack + max(win,1)) seen in reply packets
345 td_maxwin = max(max(win, 1)) + (sack - ack) seen in sent packets
346 td_maxwin += seq + len - sender.td_maxend
347 if seq + len > sender.td_maxend
348 td_end = max(seq + len) seen in sent packets
349
350 I. Upper bound for valid data: seq <= sender.td_maxend
351 II. Lower bound for valid data: seq + len >= sender.td_end - receiver.td_maxwin
352 III. Upper bound for valid (s)ack: sack <= receiver.td_end
353 IV. Lower bound for valid (s)ack: sack >= receiver.td_end - MAXACKWINDOW
354
355 where sack is the highest right edge of sack block found in the packet
356 or ack in the case of packet without SACK option.
357
358 The upper bound limit for a valid (s)ack is not ignored -
359 we doesn't have to deal with fragments.
360 */
361
362 static inline __u32 segment_seq_plus_len(__u32 seq,
363 size_t len,
364 unsigned int dataoff,
365 const struct tcphdr *tcph)
366 {
367 /* XXX Should I use payload length field in IP/IPv6 header ?
368 * - YK */
369 return (seq + len - dataoff - tcph->doff*4
370 + (tcph->syn ? 1 : 0) + (tcph->fin ? 1 : 0));
371 }
372
373 /* Fixme: what about big packets? */
374 #define MAXACKWINCONST 66000
375 #define MAXACKWINDOW(sender) \
376 ((sender)->td_maxwin > MAXACKWINCONST ? (sender)->td_maxwin \
377 : MAXACKWINCONST)
378
379 /*
380 * Simplified tcp_parse_options routine from tcp_input.c
381 */
382 static void tcp_options(const struct sk_buff *skb,
383 unsigned int dataoff,
384 const struct tcphdr *tcph,
385 struct ip_ct_tcp_state *state)
386 {
387 unsigned char buff[(15 * 4) - sizeof(struct tcphdr)];
388 const unsigned char *ptr;
389 int length = (tcph->doff*4) - sizeof(struct tcphdr);
390
391 if (!length)
392 return;
393
394 ptr = skb_header_pointer(skb, dataoff + sizeof(struct tcphdr),
395 length, buff);
396 BUG_ON(ptr == NULL);
397
398 state->td_scale =
399 state->flags = 0;
400
401 while (length > 0) {
402 int opcode=*ptr++;
403 int opsize;
404
405 switch (opcode) {
406 case TCPOPT_EOL:
407 return;
408 case TCPOPT_NOP: /* Ref: RFC 793 section 3.1 */
409 length--;
410 continue;
411 default:
412 opsize=*ptr++;
413 if (opsize < 2) /* "silly options" */
414 return;
415 if (opsize > length)
416 return; /* don't parse partial options */
417
418 if (opcode == TCPOPT_SACK_PERM
419 && opsize == TCPOLEN_SACK_PERM)
420 state->flags |= IP_CT_TCP_FLAG_SACK_PERM;
421 else if (opcode == TCPOPT_WINDOW
422 && opsize == TCPOLEN_WINDOW) {
423 state->td_scale = *(u_int8_t *)ptr;
424
425 if (state->td_scale > 14) {
426 /* See RFC1323 */
427 state->td_scale = 14;
428 }
429 state->flags |=
430 IP_CT_TCP_FLAG_WINDOW_SCALE;
431 }
432 ptr += opsize - 2;
433 length -= opsize;
434 }
435 }
436 }
437
438 static void tcp_sack(const struct sk_buff *skb, unsigned int dataoff,
439 const struct tcphdr *tcph, __u32 *sack)
440 {
441 unsigned char buff[(15 * 4) - sizeof(struct tcphdr)];
442 const unsigned char *ptr;
443 int length = (tcph->doff*4) - sizeof(struct tcphdr);
444 __u32 tmp;
445
446 if (!length)
447 return;
448
449 ptr = skb_header_pointer(skb, dataoff + sizeof(struct tcphdr),
450 length, buff);
451 BUG_ON(ptr == NULL);
452
453 /* Fast path for timestamp-only option */
454 if (length == TCPOLEN_TSTAMP_ALIGNED
455 && *(__be32 *)ptr == htonl((TCPOPT_NOP << 24)
456 | (TCPOPT_NOP << 16)
457 | (TCPOPT_TIMESTAMP << 8)
458 | TCPOLEN_TIMESTAMP))
459 return;
460
461 while (length > 0) {
462 int opcode = *ptr++;
463 int opsize, i;
464
465 switch (opcode) {
466 case TCPOPT_EOL:
467 return;
468 case TCPOPT_NOP: /* Ref: RFC 793 section 3.1 */
469 length--;
470 continue;
471 default:
472 opsize = *ptr++;
473 if (opsize < 2) /* "silly options" */
474 return;
475 if (opsize > length)
476 return; /* don't parse partial options */
477
478 if (opcode == TCPOPT_SACK
479 && opsize >= (TCPOLEN_SACK_BASE
480 + TCPOLEN_SACK_PERBLOCK)
481 && !((opsize - TCPOLEN_SACK_BASE)
482 % TCPOLEN_SACK_PERBLOCK)) {
483 for (i = 0;
484 i < (opsize - TCPOLEN_SACK_BASE);
485 i += TCPOLEN_SACK_PERBLOCK) {
486 tmp = get_unaligned_be32((__be32 *)(ptr+i)+1);
487
488 if (after(tmp, *sack))
489 *sack = tmp;
490 }
491 return;
492 }
493 ptr += opsize - 2;
494 length -= opsize;
495 }
496 }
497 }
498
499 #ifdef CONFIG_NF_NAT_NEEDED
500 static inline s16 nat_offset(const struct nf_conn *ct,
501 enum ip_conntrack_dir dir,
502 u32 seq)
503 {
504 typeof(nf_ct_nat_offset) get_offset = rcu_dereference(nf_ct_nat_offset);
505
506 return get_offset != NULL ? get_offset(ct, dir, seq) : 0;
507 }
508 #define NAT_OFFSET(ct, dir, seq) \
509 (nat_offset(ct, dir, seq))
510 #else
511 #define NAT_OFFSET(ct, dir, seq) 0
512 #endif
513
514 static bool tcp_in_window(const struct nf_conn *ct,
515 struct ip_ct_tcp *state,
516 enum ip_conntrack_dir dir,
517 unsigned int index,
518 const struct sk_buff *skb,
519 unsigned int dataoff,
520 const struct tcphdr *tcph,
521 u_int8_t pf)
522 {
523 struct net *net = nf_ct_net(ct);
524 struct nf_tcp_net *tn = tcp_pernet(net);
525 struct ip_ct_tcp_state *sender = &state->seen[dir];
526 struct ip_ct_tcp_state *receiver = &state->seen[!dir];
527 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
528 __u32 seq, ack, sack, end, win, swin;
529 s16 receiver_offset;
530 bool res;
531
532 /*
533 * Get the required data from the packet.
534 */
535 seq = ntohl(tcph->seq);
536 ack = sack = ntohl(tcph->ack_seq);
537 win = ntohs(tcph->window);
538 end = segment_seq_plus_len(seq, skb->len, dataoff, tcph);
539
540 if (receiver->flags & IP_CT_TCP_FLAG_SACK_PERM)
541 tcp_sack(skb, dataoff, tcph, &sack);
542
543 /* Take into account NAT sequence number mangling */
544 receiver_offset = NAT_OFFSET(ct, !dir, ack - 1);
545 ack -= receiver_offset;
546 sack -= receiver_offset;
547
548 pr_debug("tcp_in_window: START\n");
549 pr_debug("tcp_in_window: ");
550 nf_ct_dump_tuple(tuple);
551 pr_debug("seq=%u ack=%u+(%d) sack=%u+(%d) win=%u end=%u\n",
552 seq, ack, receiver_offset, sack, receiver_offset, win, end);
553 pr_debug("tcp_in_window: sender end=%u maxend=%u maxwin=%u scale=%i "
554 "receiver end=%u maxend=%u maxwin=%u scale=%i\n",
555 sender->td_end, sender->td_maxend, sender->td_maxwin,
556 sender->td_scale,
557 receiver->td_end, receiver->td_maxend, receiver->td_maxwin,
558 receiver->td_scale);
559
560 if (sender->td_maxwin == 0) {
561 /*
562 * Initialize sender data.
563 */
564 if (tcph->syn) {
565 /*
566 * SYN-ACK in reply to a SYN
567 * or SYN from reply direction in simultaneous open.
568 */
569 sender->td_end =
570 sender->td_maxend = end;
571 sender->td_maxwin = (win == 0 ? 1 : win);
572
573 tcp_options(skb, dataoff, tcph, sender);
574 /*
575 * RFC 1323:
576 * Both sides must send the Window Scale option
577 * to enable window scaling in either direction.
578 */
579 if (!(sender->flags & IP_CT_TCP_FLAG_WINDOW_SCALE
580 && receiver->flags & IP_CT_TCP_FLAG_WINDOW_SCALE))
581 sender->td_scale =
582 receiver->td_scale = 0;
583 if (!tcph->ack)
584 /* Simultaneous open */
585 return true;
586 } else {
587 /*
588 * We are in the middle of a connection,
589 * its history is lost for us.
590 * Let's try to use the data from the packet.
591 */
592 sender->td_end = end;
593 swin = win << sender->td_scale;
594 sender->td_maxwin = (swin == 0 ? 1 : swin);
595 sender->td_maxend = end + sender->td_maxwin;
596 /*
597 * We haven't seen traffic in the other direction yet
598 * but we have to tweak window tracking to pass III
599 * and IV until that happens.
600 */
601 if (receiver->td_maxwin == 0)
602 receiver->td_end = receiver->td_maxend = sack;
603 }
604 } else if (((state->state == TCP_CONNTRACK_SYN_SENT
605 && dir == IP_CT_DIR_ORIGINAL)
606 || (state->state == TCP_CONNTRACK_SYN_RECV
607 && dir == IP_CT_DIR_REPLY))
608 && after(end, sender->td_end)) {
609 /*
610 * RFC 793: "if a TCP is reinitialized ... then it need
611 * not wait at all; it must only be sure to use sequence
612 * numbers larger than those recently used."
613 */
614 sender->td_end =
615 sender->td_maxend = end;
616 sender->td_maxwin = (win == 0 ? 1 : win);
617
618 tcp_options(skb, dataoff, tcph, sender);
619 }
620
621 if (!(tcph->ack)) {
622 /*
623 * If there is no ACK, just pretend it was set and OK.
624 */
625 ack = sack = receiver->td_end;
626 } else if (((tcp_flag_word(tcph) & (TCP_FLAG_ACK|TCP_FLAG_RST)) ==
627 (TCP_FLAG_ACK|TCP_FLAG_RST))
628 && (ack == 0)) {
629 /*
630 * Broken TCP stacks, that set ACK in RST packets as well
631 * with zero ack value.
632 */
633 ack = sack = receiver->td_end;
634 }
635
636 if (seq == end
637 && (!tcph->rst
638 || (seq == 0 && state->state == TCP_CONNTRACK_SYN_SENT)))
639 /*
640 * Packets contains no data: we assume it is valid
641 * and check the ack value only.
642 * However RST segments are always validated by their
643 * SEQ number, except when seq == 0 (reset sent answering
644 * SYN.
645 */
646 seq = end = sender->td_end;
647
648 pr_debug("tcp_in_window: ");
649 nf_ct_dump_tuple(tuple);
650 pr_debug("seq=%u ack=%u+(%d) sack=%u+(%d) win=%u end=%u\n",
651 seq, ack, receiver_offset, sack, receiver_offset, win, end);
652 pr_debug("tcp_in_window: sender end=%u maxend=%u maxwin=%u scale=%i "
653 "receiver end=%u maxend=%u maxwin=%u scale=%i\n",
654 sender->td_end, sender->td_maxend, sender->td_maxwin,
655 sender->td_scale,
656 receiver->td_end, receiver->td_maxend, receiver->td_maxwin,
657 receiver->td_scale);
658
659 pr_debug("tcp_in_window: I=%i II=%i III=%i IV=%i\n",
660 before(seq, sender->td_maxend + 1),
661 after(end, sender->td_end - receiver->td_maxwin - 1),
662 before(sack, receiver->td_end + 1),
663 after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1));
664
665 if (before(seq, sender->td_maxend + 1) &&
666 after(end, sender->td_end - receiver->td_maxwin - 1) &&
667 before(sack, receiver->td_end + 1) &&
668 after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1)) {
669 /*
670 * Take into account window scaling (RFC 1323).
671 */
672 if (!tcph->syn)
673 win <<= sender->td_scale;
674
675 /*
676 * Update sender data.
677 */
678 swin = win + (sack - ack);
679 if (sender->td_maxwin < swin)
680 sender->td_maxwin = swin;
681 if (after(end, sender->td_end)) {
682 sender->td_end = end;
683 sender->flags |= IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
684 }
685 if (tcph->ack) {
686 if (!(sender->flags & IP_CT_TCP_FLAG_MAXACK_SET)) {
687 sender->td_maxack = ack;
688 sender->flags |= IP_CT_TCP_FLAG_MAXACK_SET;
689 } else if (after(ack, sender->td_maxack))
690 sender->td_maxack = ack;
691 }
692
693 /*
694 * Update receiver data.
695 */
696 if (receiver->td_maxwin != 0 && after(end, sender->td_maxend))
697 receiver->td_maxwin += end - sender->td_maxend;
698 if (after(sack + win, receiver->td_maxend - 1)) {
699 receiver->td_maxend = sack + win;
700 if (win == 0)
701 receiver->td_maxend++;
702 }
703 if (ack == receiver->td_end)
704 receiver->flags &= ~IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
705
706 /*
707 * Check retransmissions.
708 */
709 if (index == TCP_ACK_SET) {
710 if (state->last_dir == dir
711 && state->last_seq == seq
712 && state->last_ack == ack
713 && state->last_end == end
714 && state->last_win == win)
715 state->retrans++;
716 else {
717 state->last_dir = dir;
718 state->last_seq = seq;
719 state->last_ack = ack;
720 state->last_end = end;
721 state->last_win = win;
722 state->retrans = 0;
723 }
724 }
725 res = true;
726 } else {
727 res = false;
728 if (sender->flags & IP_CT_TCP_FLAG_BE_LIBERAL ||
729 tn->tcp_be_liberal)
730 res = true;
731 if (!res && LOG_INVALID(net, IPPROTO_TCP))
732 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
733 "nf_ct_tcp: %s ",
734 before(seq, sender->td_maxend + 1) ?
735 after(end, sender->td_end - receiver->td_maxwin - 1) ?
736 before(sack, receiver->td_end + 1) ?
737 after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1) ? "BUG"
738 : "ACK is under the lower bound (possible overly delayed ACK)"
739 : "ACK is over the upper bound (ACKed data not seen yet)"
740 : "SEQ is under the lower bound (already ACKed data retransmitted)"
741 : "SEQ is over the upper bound (over the window of the receiver)");
742 }
743
744 pr_debug("tcp_in_window: res=%u sender end=%u maxend=%u maxwin=%u "
745 "receiver end=%u maxend=%u maxwin=%u\n",
746 res, sender->td_end, sender->td_maxend, sender->td_maxwin,
747 receiver->td_end, receiver->td_maxend, receiver->td_maxwin);
748
749 return res;
750 }
751
752 /* table of valid flag combinations - PUSH, ECE and CWR are always valid */
753 static const u8 tcp_valid_flags[(TCPHDR_FIN|TCPHDR_SYN|TCPHDR_RST|TCPHDR_ACK|
754 TCPHDR_URG) + 1] =
755 {
756 [TCPHDR_SYN] = 1,
757 [TCPHDR_SYN|TCPHDR_URG] = 1,
758 [TCPHDR_SYN|TCPHDR_ACK] = 1,
759 [TCPHDR_RST] = 1,
760 [TCPHDR_RST|TCPHDR_ACK] = 1,
761 [TCPHDR_FIN|TCPHDR_ACK] = 1,
762 [TCPHDR_FIN|TCPHDR_ACK|TCPHDR_URG] = 1,
763 [TCPHDR_ACK] = 1,
764 [TCPHDR_ACK|TCPHDR_URG] = 1,
765 };
766
767 /* Protect conntrack agaist broken packets. Code taken from ipt_unclean.c. */
768 static int tcp_error(struct net *net, struct nf_conn *tmpl,
769 struct sk_buff *skb,
770 unsigned int dataoff,
771 enum ip_conntrack_info *ctinfo,
772 u_int8_t pf,
773 unsigned int hooknum)
774 {
775 const struct tcphdr *th;
776 struct tcphdr _tcph;
777 unsigned int tcplen = skb->len - dataoff;
778 u_int8_t tcpflags;
779
780 /* Smaller that minimal TCP header? */
781 th = skb_header_pointer(skb, dataoff, sizeof(_tcph), &_tcph);
782 if (th == NULL) {
783 if (LOG_INVALID(net, IPPROTO_TCP))
784 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
785 "nf_ct_tcp: short packet ");
786 return -NF_ACCEPT;
787 }
788
789 /* Not whole TCP header or malformed packet */
790 if (th->doff*4 < sizeof(struct tcphdr) || tcplen < th->doff*4) {
791 if (LOG_INVALID(net, IPPROTO_TCP))
792 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
793 "nf_ct_tcp: truncated/malformed packet ");
794 return -NF_ACCEPT;
795 }
796
797 /* Checksum invalid? Ignore.
798 * We skip checking packets on the outgoing path
799 * because the checksum is assumed to be correct.
800 */
801 /* FIXME: Source route IP option packets --RR */
802 if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
803 nf_checksum(skb, hooknum, dataoff, IPPROTO_TCP, pf)) {
804 if (LOG_INVALID(net, IPPROTO_TCP))
805 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
806 "nf_ct_tcp: bad TCP checksum ");
807 return -NF_ACCEPT;
808 }
809
810 /* Check TCP flags. */
811 tcpflags = (tcp_flag_byte(th) & ~(TCPHDR_ECE|TCPHDR_CWR|TCPHDR_PSH));
812 if (!tcp_valid_flags[tcpflags]) {
813 if (LOG_INVALID(net, IPPROTO_TCP))
814 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
815 "nf_ct_tcp: invalid TCP flag combination ");
816 return -NF_ACCEPT;
817 }
818
819 return NF_ACCEPT;
820 }
821
822 static unsigned int *tcp_get_timeouts(struct net *net)
823 {
824 return tcp_pernet(net)->timeouts;
825 }
826
827 /* Returns verdict for packet, or -1 for invalid. */
828 static int tcp_packet(struct nf_conn *ct,
829 const struct sk_buff *skb,
830 unsigned int dataoff,
831 enum ip_conntrack_info ctinfo,
832 u_int8_t pf,
833 unsigned int hooknum,
834 unsigned int *timeouts)
835 {
836 struct net *net = nf_ct_net(ct);
837 struct nf_tcp_net *tn = tcp_pernet(net);
838 struct nf_conntrack_tuple *tuple;
839 enum tcp_conntrack new_state, old_state;
840 enum ip_conntrack_dir dir;
841 const struct tcphdr *th;
842 struct tcphdr _tcph;
843 unsigned long timeout;
844 unsigned int index;
845
846 th = skb_header_pointer(skb, dataoff, sizeof(_tcph), &_tcph);
847 BUG_ON(th == NULL);
848
849 spin_lock_bh(&ct->lock);
850 old_state = ct->proto.tcp.state;
851 dir = CTINFO2DIR(ctinfo);
852 index = get_conntrack_index(th);
853 new_state = tcp_conntracks[dir][index][old_state];
854 tuple = &ct->tuplehash[dir].tuple;
855
856 switch (new_state) {
857 case TCP_CONNTRACK_SYN_SENT:
858 if (old_state < TCP_CONNTRACK_TIME_WAIT)
859 break;
860 /* RFC 1122: "When a connection is closed actively,
861 * it MUST linger in TIME-WAIT state for a time 2xMSL
862 * (Maximum Segment Lifetime). However, it MAY accept
863 * a new SYN from the remote TCP to reopen the connection
864 * directly from TIME-WAIT state, if..."
865 * We ignore the conditions because we are in the
866 * TIME-WAIT state anyway.
867 *
868 * Handle aborted connections: we and the server
869 * think there is an existing connection but the client
870 * aborts it and starts a new one.
871 */
872 if (((ct->proto.tcp.seen[dir].flags
873 | ct->proto.tcp.seen[!dir].flags)
874 & IP_CT_TCP_FLAG_CLOSE_INIT)
875 || (ct->proto.tcp.last_dir == dir
876 && ct->proto.tcp.last_index == TCP_RST_SET)) {
877 /* Attempt to reopen a closed/aborted connection.
878 * Delete this connection and look up again. */
879 spin_unlock_bh(&ct->lock);
880
881 /* Only repeat if we can actually remove the timer.
882 * Destruction may already be in progress in process
883 * context and we must give it a chance to terminate.
884 */
885 if (nf_ct_kill(ct))
886 return -NF_REPEAT;
887 return NF_DROP;
888 }
889 /* Fall through */
890 case TCP_CONNTRACK_IGNORE:
891 /* Ignored packets:
892 *
893 * Our connection entry may be out of sync, so ignore
894 * packets which may signal the real connection between
895 * the client and the server.
896 *
897 * a) SYN in ORIGINAL
898 * b) SYN/ACK in REPLY
899 * c) ACK in reply direction after initial SYN in original.
900 *
901 * If the ignored packet is invalid, the receiver will send
902 * a RST we'll catch below.
903 */
904 if (index == TCP_SYNACK_SET
905 && ct->proto.tcp.last_index == TCP_SYN_SET
906 && ct->proto.tcp.last_dir != dir
907 && ntohl(th->ack_seq) == ct->proto.tcp.last_end) {
908 /* b) This SYN/ACK acknowledges a SYN that we earlier
909 * ignored as invalid. This means that the client and
910 * the server are both in sync, while the firewall is
911 * not. We get in sync from the previously annotated
912 * values.
913 */
914 old_state = TCP_CONNTRACK_SYN_SENT;
915 new_state = TCP_CONNTRACK_SYN_RECV;
916 ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_end =
917 ct->proto.tcp.last_end;
918 ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_maxend =
919 ct->proto.tcp.last_end;
920 ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_maxwin =
921 ct->proto.tcp.last_win == 0 ?
922 1 : ct->proto.tcp.last_win;
923 ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_scale =
924 ct->proto.tcp.last_wscale;
925 ct->proto.tcp.seen[ct->proto.tcp.last_dir].flags =
926 ct->proto.tcp.last_flags;
927 memset(&ct->proto.tcp.seen[dir], 0,
928 sizeof(struct ip_ct_tcp_state));
929 break;
930 }
931 ct->proto.tcp.last_index = index;
932 ct->proto.tcp.last_dir = dir;
933 ct->proto.tcp.last_seq = ntohl(th->seq);
934 ct->proto.tcp.last_end =
935 segment_seq_plus_len(ntohl(th->seq), skb->len, dataoff, th);
936 ct->proto.tcp.last_win = ntohs(th->window);
937
938 /* a) This is a SYN in ORIGINAL. The client and the server
939 * may be in sync but we are not. In that case, we annotate
940 * the TCP options and let the packet go through. If it is a
941 * valid SYN packet, the server will reply with a SYN/ACK, and
942 * then we'll get in sync. Otherwise, the server ignores it. */
943 if (index == TCP_SYN_SET && dir == IP_CT_DIR_ORIGINAL) {
944 struct ip_ct_tcp_state seen = {};
945
946 ct->proto.tcp.last_flags =
947 ct->proto.tcp.last_wscale = 0;
948 tcp_options(skb, dataoff, th, &seen);
949 if (seen.flags & IP_CT_TCP_FLAG_WINDOW_SCALE) {
950 ct->proto.tcp.last_flags |=
951 IP_CT_TCP_FLAG_WINDOW_SCALE;
952 ct->proto.tcp.last_wscale = seen.td_scale;
953 }
954 if (seen.flags & IP_CT_TCP_FLAG_SACK_PERM) {
955 ct->proto.tcp.last_flags |=
956 IP_CT_TCP_FLAG_SACK_PERM;
957 }
958 }
959 spin_unlock_bh(&ct->lock);
960 if (LOG_INVALID(net, IPPROTO_TCP))
961 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
962 "nf_ct_tcp: invalid packet ignored in "
963 "state %s ", tcp_conntrack_names[old_state]);
964 return NF_ACCEPT;
965 case TCP_CONNTRACK_MAX:
966 /* Invalid packet */
967 pr_debug("nf_ct_tcp: Invalid dir=%i index=%u ostate=%u\n",
968 dir, get_conntrack_index(th), old_state);
969 spin_unlock_bh(&ct->lock);
970 if (LOG_INVALID(net, IPPROTO_TCP))
971 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
972 "nf_ct_tcp: invalid state ");
973 return -NF_ACCEPT;
974 case TCP_CONNTRACK_CLOSE:
975 if (index == TCP_RST_SET
976 && (ct->proto.tcp.seen[!dir].flags & IP_CT_TCP_FLAG_MAXACK_SET)
977 && before(ntohl(th->seq), ct->proto.tcp.seen[!dir].td_maxack)) {
978 /* Invalid RST */
979 spin_unlock_bh(&ct->lock);
980 if (LOG_INVALID(net, IPPROTO_TCP))
981 nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
982 "nf_ct_tcp: invalid RST ");
983 return -NF_ACCEPT;
984 }
985 if (index == TCP_RST_SET
986 && ((test_bit(IPS_SEEN_REPLY_BIT, &ct->status)
987 && ct->proto.tcp.last_index == TCP_SYN_SET)
988 || (!test_bit(IPS_ASSURED_BIT, &ct->status)
989 && ct->proto.tcp.last_index == TCP_ACK_SET))
990 && ntohl(th->ack_seq) == ct->proto.tcp.last_end) {
991 /* RST sent to invalid SYN or ACK we had let through
992 * at a) and c) above:
993 *
994 * a) SYN was in window then
995 * c) we hold a half-open connection.
996 *
997 * Delete our connection entry.
998 * We skip window checking, because packet might ACK
999 * segments we ignored. */
1000 goto in_window;
1001 }
1002 /* Just fall through */
1003 default:
1004 /* Keep compilers happy. */
1005 break;
1006 }
1007
1008 if (!tcp_in_window(ct, &ct->proto.tcp, dir, index,
1009 skb, dataoff, th, pf)) {
1010 spin_unlock_bh(&ct->lock);
1011 return -NF_ACCEPT;
1012 }
1013 in_window:
1014 /* From now on we have got in-window packets */
1015 ct->proto.tcp.last_index = index;
1016 ct->proto.tcp.last_dir = dir;
1017
1018 pr_debug("tcp_conntracks: ");
1019 nf_ct_dump_tuple(tuple);
1020 pr_debug("syn=%i ack=%i fin=%i rst=%i old=%i new=%i\n",
1021 (th->syn ? 1 : 0), (th->ack ? 1 : 0),
1022 (th->fin ? 1 : 0), (th->rst ? 1 : 0),
1023 old_state, new_state);
1024
1025 ct->proto.tcp.state = new_state;
1026 if (old_state != new_state
1027 && new_state == TCP_CONNTRACK_FIN_WAIT)
1028 ct->proto.tcp.seen[dir].flags |= IP_CT_TCP_FLAG_CLOSE_INIT;
1029
1030 if (ct->proto.tcp.retrans >= tn->tcp_max_retrans &&
1031 timeouts[new_state] > timeouts[TCP_CONNTRACK_RETRANS])
1032 timeout = timeouts[TCP_CONNTRACK_RETRANS];
1033 else if ((ct->proto.tcp.seen[0].flags | ct->proto.tcp.seen[1].flags) &
1034 IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED &&
1035 timeouts[new_state] > timeouts[TCP_CONNTRACK_UNACK])
1036 timeout = timeouts[TCP_CONNTRACK_UNACK];
1037 else
1038 timeout = timeouts[new_state];
1039 spin_unlock_bh(&ct->lock);
1040
1041 if (new_state != old_state)
1042 nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
1043
1044 if (!test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
1045 /* If only reply is a RST, we can consider ourselves not to
1046 have an established connection: this is a fairly common
1047 problem case, so we can delete the conntrack
1048 immediately. --RR */
1049 if (th->rst) {
1050 nf_ct_kill_acct(ct, ctinfo, skb);
1051 return NF_ACCEPT;
1052 }
1053 } else if (!test_bit(IPS_ASSURED_BIT, &ct->status)
1054 && (old_state == TCP_CONNTRACK_SYN_RECV
1055 || old_state == TCP_CONNTRACK_ESTABLISHED)
1056 && new_state == TCP_CONNTRACK_ESTABLISHED) {
1057 /* Set ASSURED if we see see valid ack in ESTABLISHED
1058 after SYN_RECV or a valid answer for a picked up
1059 connection. */
1060 set_bit(IPS_ASSURED_BIT, &ct->status);
1061 nf_conntrack_event_cache(IPCT_ASSURED, ct);
1062 }
1063 nf_ct_refresh_acct(ct, ctinfo, skb, timeout);
1064
1065 return NF_ACCEPT;
1066 }
1067
1068 /* Called when a new connection for this protocol found. */
1069 static bool tcp_new(struct nf_conn *ct, const struct sk_buff *skb,
1070 unsigned int dataoff, unsigned int *timeouts)
1071 {
1072 enum tcp_conntrack new_state;
1073 const struct tcphdr *th;
1074 struct tcphdr _tcph;
1075 struct net *net = nf_ct_net(ct);
1076 struct nf_tcp_net *tn = tcp_pernet(net);
1077 const struct ip_ct_tcp_state *sender = &ct->proto.tcp.seen[0];
1078 const struct ip_ct_tcp_state *receiver = &ct->proto.tcp.seen[1];
1079
1080 th = skb_header_pointer(skb, dataoff, sizeof(_tcph), &_tcph);
1081 BUG_ON(th == NULL);
1082
1083 /* Don't need lock here: this conntrack not in circulation yet */
1084 new_state = tcp_conntracks[0][get_conntrack_index(th)][TCP_CONNTRACK_NONE];
1085
1086 /* Invalid: delete conntrack */
1087 if (new_state >= TCP_CONNTRACK_MAX) {
1088 pr_debug("nf_ct_tcp: invalid new deleting.\n");
1089 return false;
1090 }
1091
1092 if (new_state == TCP_CONNTRACK_SYN_SENT) {
1093 memset(&ct->proto.tcp, 0, sizeof(ct->proto.tcp));
1094 /* SYN packet */
1095 ct->proto.tcp.seen[0].td_end =
1096 segment_seq_plus_len(ntohl(th->seq), skb->len,
1097 dataoff, th);
1098 ct->proto.tcp.seen[0].td_maxwin = ntohs(th->window);
1099 if (ct->proto.tcp.seen[0].td_maxwin == 0)
1100 ct->proto.tcp.seen[0].td_maxwin = 1;
1101 ct->proto.tcp.seen[0].td_maxend =
1102 ct->proto.tcp.seen[0].td_end;
1103
1104 tcp_options(skb, dataoff, th, &ct->proto.tcp.seen[0]);
1105 } else if (tn->tcp_loose == 0) {
1106 /* Don't try to pick up connections. */
1107 return false;
1108 } else {
1109 memset(&ct->proto.tcp, 0, sizeof(ct->proto.tcp));
1110 /*
1111 * We are in the middle of a connection,
1112 * its history is lost for us.
1113 * Let's try to use the data from the packet.
1114 */
1115 ct->proto.tcp.seen[0].td_end =
1116 segment_seq_plus_len(ntohl(th->seq), skb->len,
1117 dataoff, th);
1118 ct->proto.tcp.seen[0].td_maxwin = ntohs(th->window);
1119 if (ct->proto.tcp.seen[0].td_maxwin == 0)
1120 ct->proto.tcp.seen[0].td_maxwin = 1;
1121 ct->proto.tcp.seen[0].td_maxend =
1122 ct->proto.tcp.seen[0].td_end +
1123 ct->proto.tcp.seen[0].td_maxwin;
1124
1125 /* We assume SACK and liberal window checking to handle
1126 * window scaling */
1127 ct->proto.tcp.seen[0].flags =
1128 ct->proto.tcp.seen[1].flags = IP_CT_TCP_FLAG_SACK_PERM |
1129 IP_CT_TCP_FLAG_BE_LIBERAL;
1130 }
1131
1132 /* tcp_packet will set them */
1133 ct->proto.tcp.last_index = TCP_NONE_SET;
1134
1135 pr_debug("tcp_new: sender end=%u maxend=%u maxwin=%u scale=%i "
1136 "receiver end=%u maxend=%u maxwin=%u scale=%i\n",
1137 sender->td_end, sender->td_maxend, sender->td_maxwin,
1138 sender->td_scale,
1139 receiver->td_end, receiver->td_maxend, receiver->td_maxwin,
1140 receiver->td_scale);
1141 return true;
1142 }
1143
1144 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
1145
1146 #include <linux/netfilter/nfnetlink.h>
1147 #include <linux/netfilter/nfnetlink_conntrack.h>
1148
1149 static int tcp_to_nlattr(struct sk_buff *skb, struct nlattr *nla,
1150 struct nf_conn *ct)
1151 {
1152 struct nlattr *nest_parms;
1153 struct nf_ct_tcp_flags tmp = {};
1154
1155 spin_lock_bh(&ct->lock);
1156 nest_parms = nla_nest_start(skb, CTA_PROTOINFO_TCP | NLA_F_NESTED);
1157 if (!nest_parms)
1158 goto nla_put_failure;
1159
1160 if (nla_put_u8(skb, CTA_PROTOINFO_TCP_STATE, ct->proto.tcp.state) ||
1161 nla_put_u8(skb, CTA_PROTOINFO_TCP_WSCALE_ORIGINAL,
1162 ct->proto.tcp.seen[0].td_scale) ||
1163 nla_put_u8(skb, CTA_PROTOINFO_TCP_WSCALE_REPLY,
1164 ct->proto.tcp.seen[1].td_scale))
1165 goto nla_put_failure;
1166
1167 tmp.flags = ct->proto.tcp.seen[0].flags;
1168 if (nla_put(skb, CTA_PROTOINFO_TCP_FLAGS_ORIGINAL,
1169 sizeof(struct nf_ct_tcp_flags), &tmp))
1170 goto nla_put_failure;
1171
1172 tmp.flags = ct->proto.tcp.seen[1].flags;
1173 if (nla_put(skb, CTA_PROTOINFO_TCP_FLAGS_REPLY,
1174 sizeof(struct nf_ct_tcp_flags), &tmp))
1175 goto nla_put_failure;
1176 spin_unlock_bh(&ct->lock);
1177
1178 nla_nest_end(skb, nest_parms);
1179
1180 return 0;
1181
1182 nla_put_failure:
1183 spin_unlock_bh(&ct->lock);
1184 return -1;
1185 }
1186
1187 static const struct nla_policy tcp_nla_policy[CTA_PROTOINFO_TCP_MAX+1] = {
1188 [CTA_PROTOINFO_TCP_STATE] = { .type = NLA_U8 },
1189 [CTA_PROTOINFO_TCP_WSCALE_ORIGINAL] = { .type = NLA_U8 },
1190 [CTA_PROTOINFO_TCP_WSCALE_REPLY] = { .type = NLA_U8 },
1191 [CTA_PROTOINFO_TCP_FLAGS_ORIGINAL] = { .len = sizeof(struct nf_ct_tcp_flags) },
1192 [CTA_PROTOINFO_TCP_FLAGS_REPLY] = { .len = sizeof(struct nf_ct_tcp_flags) },
1193 };
1194
1195 static int nlattr_to_tcp(struct nlattr *cda[], struct nf_conn *ct)
1196 {
1197 struct nlattr *pattr = cda[CTA_PROTOINFO_TCP];
1198 struct nlattr *tb[CTA_PROTOINFO_TCP_MAX+1];
1199 int err;
1200
1201 /* updates could not contain anything about the private
1202 * protocol info, in that case skip the parsing */
1203 if (!pattr)
1204 return 0;
1205
1206 err = nla_parse_nested(tb, CTA_PROTOINFO_TCP_MAX, pattr, tcp_nla_policy);
1207 if (err < 0)
1208 return err;
1209
1210 if (tb[CTA_PROTOINFO_TCP_STATE] &&
1211 nla_get_u8(tb[CTA_PROTOINFO_TCP_STATE]) >= TCP_CONNTRACK_MAX)
1212 return -EINVAL;
1213
1214 spin_lock_bh(&ct->lock);
1215 if (tb[CTA_PROTOINFO_TCP_STATE])
1216 ct->proto.tcp.state = nla_get_u8(tb[CTA_PROTOINFO_TCP_STATE]);
1217
1218 if (tb[CTA_PROTOINFO_TCP_FLAGS_ORIGINAL]) {
1219 struct nf_ct_tcp_flags *attr =
1220 nla_data(tb[CTA_PROTOINFO_TCP_FLAGS_ORIGINAL]);
1221 ct->proto.tcp.seen[0].flags &= ~attr->mask;
1222 ct->proto.tcp.seen[0].flags |= attr->flags & attr->mask;
1223 }
1224
1225 if (tb[CTA_PROTOINFO_TCP_FLAGS_REPLY]) {
1226 struct nf_ct_tcp_flags *attr =
1227 nla_data(tb[CTA_PROTOINFO_TCP_FLAGS_REPLY]);
1228 ct->proto.tcp.seen[1].flags &= ~attr->mask;
1229 ct->proto.tcp.seen[1].flags |= attr->flags & attr->mask;
1230 }
1231
1232 if (tb[CTA_PROTOINFO_TCP_WSCALE_ORIGINAL] &&
1233 tb[CTA_PROTOINFO_TCP_WSCALE_REPLY] &&
1234 ct->proto.tcp.seen[0].flags & IP_CT_TCP_FLAG_WINDOW_SCALE &&
1235 ct->proto.tcp.seen[1].flags & IP_CT_TCP_FLAG_WINDOW_SCALE) {
1236 ct->proto.tcp.seen[0].td_scale =
1237 nla_get_u8(tb[CTA_PROTOINFO_TCP_WSCALE_ORIGINAL]);
1238 ct->proto.tcp.seen[1].td_scale =
1239 nla_get_u8(tb[CTA_PROTOINFO_TCP_WSCALE_REPLY]);
1240 }
1241 spin_unlock_bh(&ct->lock);
1242
1243 return 0;
1244 }
1245
1246 static int tcp_nlattr_size(void)
1247 {
1248 return nla_total_size(0) /* CTA_PROTOINFO_TCP */
1249 + nla_policy_len(tcp_nla_policy, CTA_PROTOINFO_TCP_MAX + 1);
1250 }
1251
1252 static int tcp_nlattr_tuple_size(void)
1253 {
1254 return nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1);
1255 }
1256 #endif
1257
1258 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
1259
1260 #include <linux/netfilter/nfnetlink.h>
1261 #include <linux/netfilter/nfnetlink_cttimeout.h>
1262
1263 static int tcp_timeout_nlattr_to_obj(struct nlattr *tb[],
1264 struct net *net, void *data)
1265 {
1266 unsigned int *timeouts = data;
1267 struct nf_tcp_net *tn = tcp_pernet(net);
1268 int i;
1269
1270 /* set default TCP timeouts. */
1271 for (i=0; i<TCP_CONNTRACK_TIMEOUT_MAX; i++)
1272 timeouts[i] = tn->timeouts[i];
1273
1274 if (tb[CTA_TIMEOUT_TCP_SYN_SENT]) {
1275 timeouts[TCP_CONNTRACK_SYN_SENT] =
1276 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_SYN_SENT]))*HZ;
1277 }
1278 if (tb[CTA_TIMEOUT_TCP_SYN_RECV]) {
1279 timeouts[TCP_CONNTRACK_SYN_RECV] =
1280 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_SYN_RECV]))*HZ;
1281 }
1282 if (tb[CTA_TIMEOUT_TCP_ESTABLISHED]) {
1283 timeouts[TCP_CONNTRACK_ESTABLISHED] =
1284 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_ESTABLISHED]))*HZ;
1285 }
1286 if (tb[CTA_TIMEOUT_TCP_FIN_WAIT]) {
1287 timeouts[TCP_CONNTRACK_FIN_WAIT] =
1288 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_FIN_WAIT]))*HZ;
1289 }
1290 if (tb[CTA_TIMEOUT_TCP_CLOSE_WAIT]) {
1291 timeouts[TCP_CONNTRACK_CLOSE_WAIT] =
1292 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_CLOSE_WAIT]))*HZ;
1293 }
1294 if (tb[CTA_TIMEOUT_TCP_LAST_ACK]) {
1295 timeouts[TCP_CONNTRACK_LAST_ACK] =
1296 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_LAST_ACK]))*HZ;
1297 }
1298 if (tb[CTA_TIMEOUT_TCP_TIME_WAIT]) {
1299 timeouts[TCP_CONNTRACK_TIME_WAIT] =
1300 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_TIME_WAIT]))*HZ;
1301 }
1302 if (tb[CTA_TIMEOUT_TCP_CLOSE]) {
1303 timeouts[TCP_CONNTRACK_CLOSE] =
1304 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_CLOSE]))*HZ;
1305 }
1306 if (tb[CTA_TIMEOUT_TCP_SYN_SENT2]) {
1307 timeouts[TCP_CONNTRACK_SYN_SENT2] =
1308 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_SYN_SENT2]))*HZ;
1309 }
1310 if (tb[CTA_TIMEOUT_TCP_RETRANS]) {
1311 timeouts[TCP_CONNTRACK_RETRANS] =
1312 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_RETRANS]))*HZ;
1313 }
1314 if (tb[CTA_TIMEOUT_TCP_UNACK]) {
1315 timeouts[TCP_CONNTRACK_UNACK] =
1316 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_UNACK]))*HZ;
1317 }
1318 return 0;
1319 }
1320
1321 static int
1322 tcp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
1323 {
1324 const unsigned int *timeouts = data;
1325
1326 if (nla_put_be32(skb, CTA_TIMEOUT_TCP_SYN_SENT,
1327 htonl(timeouts[TCP_CONNTRACK_SYN_SENT] / HZ)) ||
1328 nla_put_be32(skb, CTA_TIMEOUT_TCP_SYN_RECV,
1329 htonl(timeouts[TCP_CONNTRACK_SYN_RECV] / HZ)) ||
1330 nla_put_be32(skb, CTA_TIMEOUT_TCP_ESTABLISHED,
1331 htonl(timeouts[TCP_CONNTRACK_ESTABLISHED] / HZ)) ||
1332 nla_put_be32(skb, CTA_TIMEOUT_TCP_FIN_WAIT,
1333 htonl(timeouts[TCP_CONNTRACK_FIN_WAIT] / HZ)) ||
1334 nla_put_be32(skb, CTA_TIMEOUT_TCP_CLOSE_WAIT,
1335 htonl(timeouts[TCP_CONNTRACK_CLOSE_WAIT] / HZ)) ||
1336 nla_put_be32(skb, CTA_TIMEOUT_TCP_LAST_ACK,
1337 htonl(timeouts[TCP_CONNTRACK_LAST_ACK] / HZ)) ||
1338 nla_put_be32(skb, CTA_TIMEOUT_TCP_TIME_WAIT,
1339 htonl(timeouts[TCP_CONNTRACK_TIME_WAIT] / HZ)) ||
1340 nla_put_be32(skb, CTA_TIMEOUT_TCP_CLOSE,
1341 htonl(timeouts[TCP_CONNTRACK_CLOSE] / HZ)) ||
1342 nla_put_be32(skb, CTA_TIMEOUT_TCP_SYN_SENT2,
1343 htonl(timeouts[TCP_CONNTRACK_SYN_SENT2] / HZ)) ||
1344 nla_put_be32(skb, CTA_TIMEOUT_TCP_RETRANS,
1345 htonl(timeouts[TCP_CONNTRACK_RETRANS] / HZ)) ||
1346 nla_put_be32(skb, CTA_TIMEOUT_TCP_UNACK,
1347 htonl(timeouts[TCP_CONNTRACK_UNACK] / HZ)))
1348 goto nla_put_failure;
1349 return 0;
1350
1351 nla_put_failure:
1352 return -ENOSPC;
1353 }
1354
1355 static const struct nla_policy tcp_timeout_nla_policy[CTA_TIMEOUT_TCP_MAX+1] = {
1356 [CTA_TIMEOUT_TCP_SYN_SENT] = { .type = NLA_U32 },
1357 [CTA_TIMEOUT_TCP_SYN_RECV] = { .type = NLA_U32 },
1358 [CTA_TIMEOUT_TCP_ESTABLISHED] = { .type = NLA_U32 },
1359 [CTA_TIMEOUT_TCP_FIN_WAIT] = { .type = NLA_U32 },
1360 [CTA_TIMEOUT_TCP_CLOSE_WAIT] = { .type = NLA_U32 },
1361 [CTA_TIMEOUT_TCP_LAST_ACK] = { .type = NLA_U32 },
1362 [CTA_TIMEOUT_TCP_TIME_WAIT] = { .type = NLA_U32 },
1363 [CTA_TIMEOUT_TCP_CLOSE] = { .type = NLA_U32 },
1364 [CTA_TIMEOUT_TCP_SYN_SENT2] = { .type = NLA_U32 },
1365 };
1366 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
1367
1368 #ifdef CONFIG_SYSCTL
1369 static struct ctl_table tcp_sysctl_table[] = {
1370 {
1371 .procname = "nf_conntrack_tcp_timeout_syn_sent",
1372 .maxlen = sizeof(unsigned int),
1373 .mode = 0644,
1374 .proc_handler = proc_dointvec_jiffies,
1375 },
1376 {
1377 .procname = "nf_conntrack_tcp_timeout_syn_recv",
1378 .maxlen = sizeof(unsigned int),
1379 .mode = 0644,
1380 .proc_handler = proc_dointvec_jiffies,
1381 },
1382 {
1383 .procname = "nf_conntrack_tcp_timeout_established",
1384 .maxlen = sizeof(unsigned int),
1385 .mode = 0644,
1386 .proc_handler = proc_dointvec_jiffies,
1387 },
1388 {
1389 .procname = "nf_conntrack_tcp_timeout_fin_wait",
1390 .maxlen = sizeof(unsigned int),
1391 .mode = 0644,
1392 .proc_handler = proc_dointvec_jiffies,
1393 },
1394 {
1395 .procname = "nf_conntrack_tcp_timeout_close_wait",
1396 .maxlen = sizeof(unsigned int),
1397 .mode = 0644,
1398 .proc_handler = proc_dointvec_jiffies,
1399 },
1400 {
1401 .procname = "nf_conntrack_tcp_timeout_last_ack",
1402 .maxlen = sizeof(unsigned int),
1403 .mode = 0644,
1404 .proc_handler = proc_dointvec_jiffies,
1405 },
1406 {
1407 .procname = "nf_conntrack_tcp_timeout_time_wait",
1408 .maxlen = sizeof(unsigned int),
1409 .mode = 0644,
1410 .proc_handler = proc_dointvec_jiffies,
1411 },
1412 {
1413 .procname = "nf_conntrack_tcp_timeout_close",
1414 .maxlen = sizeof(unsigned int),
1415 .mode = 0644,
1416 .proc_handler = proc_dointvec_jiffies,
1417 },
1418 {
1419 .procname = "nf_conntrack_tcp_timeout_max_retrans",
1420 .maxlen = sizeof(unsigned int),
1421 .mode = 0644,
1422 .proc_handler = proc_dointvec_jiffies,
1423 },
1424 {
1425 .procname = "nf_conntrack_tcp_timeout_unacknowledged",
1426 .maxlen = sizeof(unsigned int),
1427 .mode = 0644,
1428 .proc_handler = proc_dointvec_jiffies,
1429 },
1430 {
1431 .procname = "nf_conntrack_tcp_loose",
1432 .maxlen = sizeof(unsigned int),
1433 .mode = 0644,
1434 .proc_handler = proc_dointvec,
1435 },
1436 {
1437 .procname = "nf_conntrack_tcp_be_liberal",
1438 .maxlen = sizeof(unsigned int),
1439 .mode = 0644,
1440 .proc_handler = proc_dointvec,
1441 },
1442 {
1443 .procname = "nf_conntrack_tcp_max_retrans",
1444 .maxlen = sizeof(unsigned int),
1445 .mode = 0644,
1446 .proc_handler = proc_dointvec,
1447 },
1448 { }
1449 };
1450
1451 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
1452 static struct ctl_table tcp_compat_sysctl_table[] = {
1453 {
1454 .procname = "ip_conntrack_tcp_timeout_syn_sent",
1455 .maxlen = sizeof(unsigned int),
1456 .mode = 0644,
1457 .proc_handler = proc_dointvec_jiffies,
1458 },
1459 {
1460 .procname = "ip_conntrack_tcp_timeout_syn_sent2",
1461 .maxlen = sizeof(unsigned int),
1462 .mode = 0644,
1463 .proc_handler = proc_dointvec_jiffies,
1464 },
1465 {
1466 .procname = "ip_conntrack_tcp_timeout_syn_recv",
1467 .maxlen = sizeof(unsigned int),
1468 .mode = 0644,
1469 .proc_handler = proc_dointvec_jiffies,
1470 },
1471 {
1472 .procname = "ip_conntrack_tcp_timeout_established",
1473 .maxlen = sizeof(unsigned int),
1474 .mode = 0644,
1475 .proc_handler = proc_dointvec_jiffies,
1476 },
1477 {
1478 .procname = "ip_conntrack_tcp_timeout_fin_wait",
1479 .maxlen = sizeof(unsigned int),
1480 .mode = 0644,
1481 .proc_handler = proc_dointvec_jiffies,
1482 },
1483 {
1484 .procname = "ip_conntrack_tcp_timeout_close_wait",
1485 .maxlen = sizeof(unsigned int),
1486 .mode = 0644,
1487 .proc_handler = proc_dointvec_jiffies,
1488 },
1489 {
1490 .procname = "ip_conntrack_tcp_timeout_last_ack",
1491 .maxlen = sizeof(unsigned int),
1492 .mode = 0644,
1493 .proc_handler = proc_dointvec_jiffies,
1494 },
1495 {
1496 .procname = "ip_conntrack_tcp_timeout_time_wait",
1497 .maxlen = sizeof(unsigned int),
1498 .mode = 0644,
1499 .proc_handler = proc_dointvec_jiffies,
1500 },
1501 {
1502 .procname = "ip_conntrack_tcp_timeout_close",
1503 .maxlen = sizeof(unsigned int),
1504 .mode = 0644,
1505 .proc_handler = proc_dointvec_jiffies,
1506 },
1507 {
1508 .procname = "ip_conntrack_tcp_timeout_max_retrans",
1509 .maxlen = sizeof(unsigned int),
1510 .mode = 0644,
1511 .proc_handler = proc_dointvec_jiffies,
1512 },
1513 {
1514 .procname = "ip_conntrack_tcp_loose",
1515 .maxlen = sizeof(unsigned int),
1516 .mode = 0644,
1517 .proc_handler = proc_dointvec,
1518 },
1519 {
1520 .procname = "ip_conntrack_tcp_be_liberal",
1521 .maxlen = sizeof(unsigned int),
1522 .mode = 0644,
1523 .proc_handler = proc_dointvec,
1524 },
1525 {
1526 .procname = "ip_conntrack_tcp_max_retrans",
1527 .maxlen = sizeof(unsigned int),
1528 .mode = 0644,
1529 .proc_handler = proc_dointvec,
1530 },
1531 { }
1532 };
1533 #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
1534 #endif /* CONFIG_SYSCTL */
1535
1536 static int tcp_kmemdup_sysctl_table(struct nf_proto_net *pn,
1537 struct nf_tcp_net *tn)
1538 {
1539 #ifdef CONFIG_SYSCTL
1540 if (pn->ctl_table)
1541 return 0;
1542
1543 pn->ctl_table = kmemdup(tcp_sysctl_table,
1544 sizeof(tcp_sysctl_table),
1545 GFP_KERNEL);
1546 if (!pn->ctl_table)
1547 return -ENOMEM;
1548
1549 pn->ctl_table[0].data = &tn->timeouts[TCP_CONNTRACK_SYN_SENT];
1550 pn->ctl_table[1].data = &tn->timeouts[TCP_CONNTRACK_SYN_RECV];
1551 pn->ctl_table[2].data = &tn->timeouts[TCP_CONNTRACK_ESTABLISHED];
1552 pn->ctl_table[3].data = &tn->timeouts[TCP_CONNTRACK_FIN_WAIT];
1553 pn->ctl_table[4].data = &tn->timeouts[TCP_CONNTRACK_CLOSE_WAIT];
1554 pn->ctl_table[5].data = &tn->timeouts[TCP_CONNTRACK_LAST_ACK];
1555 pn->ctl_table[6].data = &tn->timeouts[TCP_CONNTRACK_TIME_WAIT];
1556 pn->ctl_table[7].data = &tn->timeouts[TCP_CONNTRACK_CLOSE];
1557 pn->ctl_table[8].data = &tn->timeouts[TCP_CONNTRACK_RETRANS];
1558 pn->ctl_table[9].data = &tn->timeouts[TCP_CONNTRACK_UNACK];
1559 pn->ctl_table[10].data = &tn->tcp_loose;
1560 pn->ctl_table[11].data = &tn->tcp_be_liberal;
1561 pn->ctl_table[12].data = &tn->tcp_max_retrans;
1562 #endif
1563 return 0;
1564 }
1565
1566 static int tcp_kmemdup_compat_sysctl_table(struct nf_proto_net *pn,
1567 struct nf_tcp_net *tn)
1568 {
1569 #ifdef CONFIG_SYSCTL
1570 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
1571 pn->ctl_compat_table = kmemdup(tcp_compat_sysctl_table,
1572 sizeof(tcp_compat_sysctl_table),
1573 GFP_KERNEL);
1574 if (!pn->ctl_compat_table)
1575 return -ENOMEM;
1576
1577 pn->ctl_compat_table[0].data = &tn->timeouts[TCP_CONNTRACK_SYN_SENT];
1578 pn->ctl_compat_table[1].data = &tn->timeouts[TCP_CONNTRACK_SYN_SENT2];
1579 pn->ctl_compat_table[2].data = &tn->timeouts[TCP_CONNTRACK_SYN_RECV];
1580 pn->ctl_compat_table[3].data = &tn->timeouts[TCP_CONNTRACK_ESTABLISHED];
1581 pn->ctl_compat_table[4].data = &tn->timeouts[TCP_CONNTRACK_FIN_WAIT];
1582 pn->ctl_compat_table[5].data = &tn->timeouts[TCP_CONNTRACK_CLOSE_WAIT];
1583 pn->ctl_compat_table[6].data = &tn->timeouts[TCP_CONNTRACK_LAST_ACK];
1584 pn->ctl_compat_table[7].data = &tn->timeouts[TCP_CONNTRACK_TIME_WAIT];
1585 pn->ctl_compat_table[8].data = &tn->timeouts[TCP_CONNTRACK_CLOSE];
1586 pn->ctl_compat_table[9].data = &tn->timeouts[TCP_CONNTRACK_RETRANS];
1587 pn->ctl_compat_table[10].data = &tn->tcp_loose;
1588 pn->ctl_compat_table[11].data = &tn->tcp_be_liberal;
1589 pn->ctl_compat_table[12].data = &tn->tcp_max_retrans;
1590 #endif
1591 #endif
1592 return 0;
1593 }
1594
1595 static int tcp_init_net(struct net *net, u_int16_t proto)
1596 {
1597 int ret;
1598 struct nf_tcp_net *tn = tcp_pernet(net);
1599 struct nf_proto_net *pn = &tn->pn;
1600
1601 if (!pn->users) {
1602 int i;
1603
1604 for (i = 0; i < TCP_CONNTRACK_TIMEOUT_MAX; i++)
1605 tn->timeouts[i] = tcp_timeouts[i];
1606
1607 tn->tcp_loose = nf_ct_tcp_loose;
1608 tn->tcp_be_liberal = nf_ct_tcp_be_liberal;
1609 tn->tcp_max_retrans = nf_ct_tcp_max_retrans;
1610 }
1611
1612 if (proto == AF_INET) {
1613 ret = tcp_kmemdup_compat_sysctl_table(pn, tn);
1614 if (ret < 0)
1615 return ret;
1616
1617 ret = tcp_kmemdup_sysctl_table(pn, tn);
1618 if (ret < 0)
1619 nf_ct_kfree_compat_sysctl_table(pn);
1620 } else
1621 ret = tcp_kmemdup_sysctl_table(pn, tn);
1622
1623 return ret;
1624 }
1625
1626 static struct nf_proto_net *tcp_get_net_proto(struct net *net)
1627 {
1628 return &net->ct.nf_ct_proto.tcp.pn;
1629 }
1630
1631 struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp4 __read_mostly =
1632 {
1633 .l3proto = PF_INET,
1634 .l4proto = IPPROTO_TCP,
1635 .name = "tcp",
1636 .pkt_to_tuple = tcp_pkt_to_tuple,
1637 .invert_tuple = tcp_invert_tuple,
1638 .print_tuple = tcp_print_tuple,
1639 .print_conntrack = tcp_print_conntrack,
1640 .packet = tcp_packet,
1641 .get_timeouts = tcp_get_timeouts,
1642 .new = tcp_new,
1643 .error = tcp_error,
1644 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
1645 .to_nlattr = tcp_to_nlattr,
1646 .nlattr_size = tcp_nlattr_size,
1647 .from_nlattr = nlattr_to_tcp,
1648 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
1649 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
1650 .nlattr_tuple_size = tcp_nlattr_tuple_size,
1651 .nla_policy = nf_ct_port_nla_policy,
1652 #endif
1653 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
1654 .ctnl_timeout = {
1655 .nlattr_to_obj = tcp_timeout_nlattr_to_obj,
1656 .obj_to_nlattr = tcp_timeout_obj_to_nlattr,
1657 .nlattr_max = CTA_TIMEOUT_TCP_MAX,
1658 .obj_size = sizeof(unsigned int) *
1659 TCP_CONNTRACK_TIMEOUT_MAX,
1660 .nla_policy = tcp_timeout_nla_policy,
1661 },
1662 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
1663 .init_net = tcp_init_net,
1664 .get_net_proto = tcp_get_net_proto,
1665 };
1666 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_tcp4);
1667
1668 struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp6 __read_mostly =
1669 {
1670 .l3proto = PF_INET6,
1671 .l4proto = IPPROTO_TCP,
1672 .name = "tcp",
1673 .pkt_to_tuple = tcp_pkt_to_tuple,
1674 .invert_tuple = tcp_invert_tuple,
1675 .print_tuple = tcp_print_tuple,
1676 .print_conntrack = tcp_print_conntrack,
1677 .packet = tcp_packet,
1678 .get_timeouts = tcp_get_timeouts,
1679 .new = tcp_new,
1680 .error = tcp_error,
1681 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
1682 .to_nlattr = tcp_to_nlattr,
1683 .nlattr_size = tcp_nlattr_size,
1684 .from_nlattr = nlattr_to_tcp,
1685 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
1686 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
1687 .nlattr_tuple_size = tcp_nlattr_tuple_size,
1688 .nla_policy = nf_ct_port_nla_policy,
1689 #endif
1690 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
1691 .ctnl_timeout = {
1692 .nlattr_to_obj = tcp_timeout_nlattr_to_obj,
1693 .obj_to_nlattr = tcp_timeout_obj_to_nlattr,
1694 .nlattr_max = CTA_TIMEOUT_TCP_MAX,
1695 .obj_size = sizeof(unsigned int) *
1696 TCP_CONNTRACK_TIMEOUT_MAX,
1697 .nla_policy = tcp_timeout_nla_policy,
1698 },
1699 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
1700 .init_net = tcp_init_net,
1701 .get_net_proto = tcp_get_net_proto,
1702 };
1703 EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_tcp6);
Linux kernel - Deliverables
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