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8#include <linux/types.h>
9#include <linux/timer.h>
10#include <linux/module.h>
11#include <linux/in.h>
12#include <linux/tcp.h>
13#include <linux/spinlock.h>
14#include <linux/skbuff.h>
15#include <linux/ipv6.h>
16#include <net/ip6_checksum.h>
17#include <asm/unaligned.h>
18
19#include <net/tcp.h>
20
21#include <linux/netfilter.h>
22#include <linux/netfilter_ipv4.h>
23#include <linux/netfilter_ipv6.h>
24#include <net/netfilter/nf_conntrack.h>
25#include <net/netfilter/nf_conntrack_l4proto.h>
26#include <net/netfilter/nf_conntrack_ecache.h>
27#include <net/netfilter/nf_conntrack_seqadj.h>
28#include <net/netfilter/nf_conntrack_synproxy.h>
29#include <net/netfilter/nf_conntrack_timeout.h>
30#include <net/netfilter/nf_log.h>
31#include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
32#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
33
34
35
36
37static const char *const tcp_conntrack_names[] = {
38 "NONE",
39 "SYN_SENT",
40 "SYN_RECV",
41 "ESTABLISHED",
42 "FIN_WAIT",
43 "CLOSE_WAIT",
44 "LAST_ACK",
45 "TIME_WAIT",
46 "CLOSE",
47 "SYN_SENT2",
48};
49
50#define SECS * HZ
51#define MINS * 60 SECS
52#define HOURS * 60 MINS
53#define DAYS * 24 HOURS
54
55static const unsigned int tcp_timeouts[TCP_CONNTRACK_TIMEOUT_MAX] = {
56 [TCP_CONNTRACK_SYN_SENT] = 2 MINS,
57 [TCP_CONNTRACK_SYN_RECV] = 60 SECS,
58 [TCP_CONNTRACK_ESTABLISHED] = 5 DAYS,
59 [TCP_CONNTRACK_FIN_WAIT] = 2 MINS,
60 [TCP_CONNTRACK_CLOSE_WAIT] = 60 SECS,
61 [TCP_CONNTRACK_LAST_ACK] = 30 SECS,
62 [TCP_CONNTRACK_TIME_WAIT] = 2 MINS,
63 [TCP_CONNTRACK_CLOSE] = 10 SECS,
64 [TCP_CONNTRACK_SYN_SENT2] = 2 MINS,
65
66
67
68 [TCP_CONNTRACK_RETRANS] = 5 MINS,
69 [TCP_CONNTRACK_UNACK] = 5 MINS,
70};
71
72#define sNO TCP_CONNTRACK_NONE
73#define sSS TCP_CONNTRACK_SYN_SENT
74#define sSR TCP_CONNTRACK_SYN_RECV
75#define sES TCP_CONNTRACK_ESTABLISHED
76#define sFW TCP_CONNTRACK_FIN_WAIT
77#define sCW TCP_CONNTRACK_CLOSE_WAIT
78#define sLA TCP_CONNTRACK_LAST_ACK
79#define sTW TCP_CONNTRACK_TIME_WAIT
80#define sCL TCP_CONNTRACK_CLOSE
81#define sS2 TCP_CONNTRACK_SYN_SENT2
82#define sIV TCP_CONNTRACK_MAX
83#define sIG TCP_CONNTRACK_IGNORE
84
85
86enum tcp_bit_set {
87 TCP_SYN_SET,
88 TCP_SYNACK_SET,
89 TCP_FIN_SET,
90 TCP_ACK_SET,
91 TCP_RST_SET,
92 TCP_NONE_SET,
93};
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128static const u8 tcp_conntracks[2][6][TCP_CONNTRACK_MAX] = {
129 {
130
131
132 { sSS, sSS, sIG, sIG, sIG, sIG, sIG, sSS, sSS, sS2 },
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149 { sIV, sIV, sSR, sIV, sIV, sIV, sIV, sIV, sIV, sSR },
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163 { sIV, sIV, sFW, sFW, sLA, sLA, sLA, sTW, sCL, sIV },
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180 { sES, sIV, sES, sES, sCW, sCW, sTW, sTW, sCL, sIV },
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194 { sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL },
195 { sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV }
196 },
197 {
198
199
200 { sIV, sS2, sIV, sIV, sIV, sIV, sIV, sSS, sIV, sS2 },
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214 { sIV, sSR, sIG, sIG, sIG, sIG, sIG, sIG, sIG, sSR },
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227 { sIV, sIV, sFW, sFW, sLA, sLA, sLA, sTW, sCL, sIV },
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240 { sIV, sIG, sSR, sES, sCW, sCW, sTW, sTW, sCL, sIG },
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253 { sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL },
254 { sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV }
255 }
256};
257
258#ifdef CONFIG_NF_CONNTRACK_PROCFS
259
260static void tcp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
261{
262 if (test_bit(IPS_OFFLOAD_BIT, &ct->status))
263 return;
264
265 seq_printf(s, "%s ", tcp_conntrack_names[ct->proto.tcp.state]);
266}
267#endif
268
269static unsigned int get_conntrack_index(const struct tcphdr *tcph)
270{
271 if (tcph->rst) return TCP_RST_SET;
272 else if (tcph->syn) return (tcph->ack ? TCP_SYNACK_SET : TCP_SYN_SET);
273 else if (tcph->fin) return TCP_FIN_SET;
274 else if (tcph->ack) return TCP_ACK_SET;
275 else return TCP_NONE_SET;
276}
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307static inline __u32 segment_seq_plus_len(__u32 seq,
308 size_t len,
309 unsigned int dataoff,
310 const struct tcphdr *tcph)
311{
312
313
314 return (seq + len - dataoff - tcph->doff*4
315 + (tcph->syn ? 1 : 0) + (tcph->fin ? 1 : 0));
316}
317
318
319#define MAXACKWINCONST 66000
320#define MAXACKWINDOW(sender) \
321 ((sender)->td_maxwin > MAXACKWINCONST ? (sender)->td_maxwin \
322 : MAXACKWINCONST)
323
324
325
326
327static void tcp_options(const struct sk_buff *skb,
328 unsigned int dataoff,
329 const struct tcphdr *tcph,
330 struct ip_ct_tcp_state *state)
331{
332 unsigned char buff[(15 * 4) - sizeof(struct tcphdr)];
333 const unsigned char *ptr;
334 int length = (tcph->doff*4) - sizeof(struct tcphdr);
335
336 if (!length)
337 return;
338
339 ptr = skb_header_pointer(skb, dataoff + sizeof(struct tcphdr),
340 length, buff);
341 if (!ptr)
342 return;
343
344 state->td_scale =
345 state->flags = 0;
346
347 while (length > 0) {
348 int opcode=*ptr++;
349 int opsize;
350
351 switch (opcode) {
352 case TCPOPT_EOL:
353 return;
354 case TCPOPT_NOP:
355 length--;
356 continue;
357 default:
358 if (length < 2)
359 return;
360 opsize=*ptr++;
361 if (opsize < 2)
362 return;
363 if (opsize > length)
364 return;
365
366 if (opcode == TCPOPT_SACK_PERM
367 && opsize == TCPOLEN_SACK_PERM)
368 state->flags |= IP_CT_TCP_FLAG_SACK_PERM;
369 else if (opcode == TCPOPT_WINDOW
370 && opsize == TCPOLEN_WINDOW) {
371 state->td_scale = *(u_int8_t *)ptr;
372
373 if (state->td_scale > TCP_MAX_WSCALE)
374 state->td_scale = TCP_MAX_WSCALE;
375
376 state->flags |=
377 IP_CT_TCP_FLAG_WINDOW_SCALE;
378 }
379 ptr += opsize - 2;
380 length -= opsize;
381 }
382 }
383}
384
385static void tcp_sack(const struct sk_buff *skb, unsigned int dataoff,
386 const struct tcphdr *tcph, __u32 *sack)
387{
388 unsigned char buff[(15 * 4) - sizeof(struct tcphdr)];
389 const unsigned char *ptr;
390 int length = (tcph->doff*4) - sizeof(struct tcphdr);
391 __u32 tmp;
392
393 if (!length)
394 return;
395
396 ptr = skb_header_pointer(skb, dataoff + sizeof(struct tcphdr),
397 length, buff);
398 if (!ptr)
399 return;
400
401
402 if (length == TCPOLEN_TSTAMP_ALIGNED
403 && *(__be32 *)ptr == htonl((TCPOPT_NOP << 24)
404 | (TCPOPT_NOP << 16)
405 | (TCPOPT_TIMESTAMP << 8)
406 | TCPOLEN_TIMESTAMP))
407 return;
408
409 while (length > 0) {
410 int opcode = *ptr++;
411 int opsize, i;
412
413 switch (opcode) {
414 case TCPOPT_EOL:
415 return;
416 case TCPOPT_NOP:
417 length--;
418 continue;
419 default:
420 if (length < 2)
421 return;
422 opsize = *ptr++;
423 if (opsize < 2)
424 return;
425 if (opsize > length)
426 return;
427
428 if (opcode == TCPOPT_SACK
429 && opsize >= (TCPOLEN_SACK_BASE
430 + TCPOLEN_SACK_PERBLOCK)
431 && !((opsize - TCPOLEN_SACK_BASE)
432 % TCPOLEN_SACK_PERBLOCK)) {
433 for (i = 0;
434 i < (opsize - TCPOLEN_SACK_BASE);
435 i += TCPOLEN_SACK_PERBLOCK) {
436 tmp = get_unaligned_be32((__be32 *)(ptr+i)+1);
437
438 if (after(tmp, *sack))
439 *sack = tmp;
440 }
441 return;
442 }
443 ptr += opsize - 2;
444 length -= opsize;
445 }
446 }
447}
448
449static bool tcp_in_window(struct nf_conn *ct,
450 enum ip_conntrack_dir dir,
451 unsigned int index,
452 const struct sk_buff *skb,
453 unsigned int dataoff,
454 const struct tcphdr *tcph,
455 const struct nf_hook_state *hook_state)
456{
457 struct ip_ct_tcp *state = &ct->proto.tcp;
458 struct net *net = nf_ct_net(ct);
459 struct nf_tcp_net *tn = nf_tcp_pernet(net);
460 struct ip_ct_tcp_state *sender = &state->seen[dir];
461 struct ip_ct_tcp_state *receiver = &state->seen[!dir];
462 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
463 __u32 seq, ack, sack, end, win, swin;
464 u16 win_raw;
465 s32 receiver_offset;
466 bool res, in_recv_win;
467
468
469
470
471 seq = ntohl(tcph->seq);
472 ack = sack = ntohl(tcph->ack_seq);
473 win_raw = ntohs(tcph->window);
474 win = win_raw;
475 end = segment_seq_plus_len(seq, skb->len, dataoff, tcph);
476
477 if (receiver->flags & IP_CT_TCP_FLAG_SACK_PERM)
478 tcp_sack(skb, dataoff, tcph, &sack);
479
480
481 receiver_offset = nf_ct_seq_offset(ct, !dir, ack - 1);
482 ack -= receiver_offset;
483 sack -= receiver_offset;
484
485 pr_debug("tcp_in_window: START\n");
486 pr_debug("tcp_in_window: ");
487 nf_ct_dump_tuple(tuple);
488 pr_debug("seq=%u ack=%u+(%d) sack=%u+(%d) win=%u end=%u\n",
489 seq, ack, receiver_offset, sack, receiver_offset, win, end);
490 pr_debug("tcp_in_window: sender end=%u maxend=%u maxwin=%u scale=%i "
491 "receiver end=%u maxend=%u maxwin=%u scale=%i\n",
492 sender->td_end, sender->td_maxend, sender->td_maxwin,
493 sender->td_scale,
494 receiver->td_end, receiver->td_maxend, receiver->td_maxwin,
495 receiver->td_scale);
496
497 if (sender->td_maxwin == 0) {
498
499
500
501 if (tcph->syn) {
502
503
504
505
506 sender->td_end =
507 sender->td_maxend = end;
508 sender->td_maxwin = (win == 0 ? 1 : win);
509
510 tcp_options(skb, dataoff, tcph, sender);
511
512
513
514
515
516 if (!(sender->flags & IP_CT_TCP_FLAG_WINDOW_SCALE
517 && receiver->flags & IP_CT_TCP_FLAG_WINDOW_SCALE))
518 sender->td_scale =
519 receiver->td_scale = 0;
520 if (!tcph->ack)
521
522 return true;
523 } else {
524
525
526
527
528
529 sender->td_end = end;
530 swin = win << sender->td_scale;
531 sender->td_maxwin = (swin == 0 ? 1 : swin);
532 sender->td_maxend = end + sender->td_maxwin;
533 if (receiver->td_maxwin == 0) {
534
535
536
537
538
539 receiver->td_end = receiver->td_maxend = sack;
540 } else if (sack == receiver->td_end + 1) {
541
542
543
544 receiver->td_end++;
545 }
546
547 }
548 } else if (((state->state == TCP_CONNTRACK_SYN_SENT
549 && dir == IP_CT_DIR_ORIGINAL)
550 || (state->state == TCP_CONNTRACK_SYN_RECV
551 && dir == IP_CT_DIR_REPLY))
552 && after(end, sender->td_end)) {
553
554
555
556
557
558 sender->td_end =
559 sender->td_maxend = end;
560 sender->td_maxwin = (win == 0 ? 1 : win);
561
562 tcp_options(skb, dataoff, tcph, sender);
563 }
564
565 if (!(tcph->ack)) {
566
567
568
569 ack = sack = receiver->td_end;
570 } else if (((tcp_flag_word(tcph) & (TCP_FLAG_ACK|TCP_FLAG_RST)) ==
571 (TCP_FLAG_ACK|TCP_FLAG_RST))
572 && (ack == 0)) {
573
574
575
576
577 ack = sack = receiver->td_end;
578 }
579
580 if (tcph->rst && seq == 0 && state->state == TCP_CONNTRACK_SYN_SENT)
581
582
583
584 seq = end = sender->td_end;
585
586 pr_debug("tcp_in_window: ");
587 nf_ct_dump_tuple(tuple);
588 pr_debug("seq=%u ack=%u+(%d) sack=%u+(%d) win=%u end=%u\n",
589 seq, ack, receiver_offset, sack, receiver_offset, win, end);
590 pr_debug("tcp_in_window: sender end=%u maxend=%u maxwin=%u scale=%i "
591 "receiver end=%u maxend=%u maxwin=%u scale=%i\n",
592 sender->td_end, sender->td_maxend, sender->td_maxwin,
593 sender->td_scale,
594 receiver->td_end, receiver->td_maxend, receiver->td_maxwin,
595 receiver->td_scale);
596
597
598 in_recv_win = !receiver->td_maxwin ||
599 after(end, sender->td_end - receiver->td_maxwin - 1);
600
601 pr_debug("tcp_in_window: I=%i II=%i III=%i IV=%i\n",
602 before(seq, sender->td_maxend + 1),
603 (in_recv_win ? 1 : 0),
604 before(sack, receiver->td_end + 1),
605 after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1));
606
607 if (before(seq, sender->td_maxend + 1) &&
608 in_recv_win &&
609 before(sack, receiver->td_end + 1) &&
610 after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1)) {
611
612
613
614 if (!tcph->syn)
615 win <<= sender->td_scale;
616
617
618
619
620 swin = win + (sack - ack);
621 if (sender->td_maxwin < swin)
622 sender->td_maxwin = swin;
623 if (after(end, sender->td_end)) {
624 sender->td_end = end;
625 sender->flags |= IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
626 }
627 if (tcph->ack) {
628 if (!(sender->flags & IP_CT_TCP_FLAG_MAXACK_SET)) {
629 sender->td_maxack = ack;
630 sender->flags |= IP_CT_TCP_FLAG_MAXACK_SET;
631 } else if (after(ack, sender->td_maxack))
632 sender->td_maxack = ack;
633 }
634
635
636
637
638 if (receiver->td_maxwin != 0 && after(end, sender->td_maxend))
639 receiver->td_maxwin += end - sender->td_maxend;
640 if (after(sack + win, receiver->td_maxend - 1)) {
641 receiver->td_maxend = sack + win;
642 if (win == 0)
643 receiver->td_maxend++;
644 }
645 if (ack == receiver->td_end)
646 receiver->flags &= ~IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
647
648
649
650
651 if (index == TCP_ACK_SET) {
652 if (state->last_dir == dir
653 && state->last_seq == seq
654 && state->last_ack == ack
655 && state->last_end == end
656 && state->last_win == win_raw)
657 state->retrans++;
658 else {
659 state->last_dir = dir;
660 state->last_seq = seq;
661 state->last_ack = ack;
662 state->last_end = end;
663 state->last_win = win_raw;
664 state->retrans = 0;
665 }
666 }
667 res = true;
668 } else {
669 res = false;
670 if (sender->flags & IP_CT_TCP_FLAG_BE_LIBERAL ||
671 tn->tcp_be_liberal)
672 res = true;
673 if (!res) {
674 nf_ct_l4proto_log_invalid(skb, ct, hook_state,
675 "%s",
676 before(seq, sender->td_maxend + 1) ?
677 in_recv_win ?
678 before(sack, receiver->td_end + 1) ?
679 after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1) ? "BUG"
680 : "ACK is under the lower bound (possible overly delayed ACK)"
681 : "ACK is over the upper bound (ACKed data not seen yet)"
682 : "SEQ is under the lower bound (already ACKed data retransmitted)"
683 : "SEQ is over the upper bound (over the window of the receiver)");
684 }
685 }
686
687 pr_debug("tcp_in_window: res=%u sender end=%u maxend=%u maxwin=%u "
688 "receiver end=%u maxend=%u maxwin=%u\n",
689 res, sender->td_end, sender->td_maxend, sender->td_maxwin,
690 receiver->td_end, receiver->td_maxend, receiver->td_maxwin);
691
692 return res;
693}
694
695
696static const u8 tcp_valid_flags[(TCPHDR_FIN|TCPHDR_SYN|TCPHDR_RST|TCPHDR_ACK|
697 TCPHDR_URG) + 1] =
698{
699 [TCPHDR_SYN] = 1,
700 [TCPHDR_SYN|TCPHDR_URG] = 1,
701 [TCPHDR_SYN|TCPHDR_ACK] = 1,
702 [TCPHDR_RST] = 1,
703 [TCPHDR_RST|TCPHDR_ACK] = 1,
704 [TCPHDR_FIN|TCPHDR_ACK] = 1,
705 [TCPHDR_FIN|TCPHDR_ACK|TCPHDR_URG] = 1,
706 [TCPHDR_ACK] = 1,
707 [TCPHDR_ACK|TCPHDR_URG] = 1,
708};
709
710static void tcp_error_log(const struct sk_buff *skb,
711 const struct nf_hook_state *state,
712 const char *msg)
713{
714 nf_l4proto_log_invalid(skb, state, IPPROTO_TCP, "%s", msg);
715}
716
717
718static bool tcp_error(const struct tcphdr *th,
719 struct sk_buff *skb,
720 unsigned int dataoff,
721 const struct nf_hook_state *state)
722{
723 unsigned int tcplen = skb->len - dataoff;
724 u8 tcpflags;
725
726
727 if (th->doff*4 < sizeof(struct tcphdr) || tcplen < th->doff*4) {
728 tcp_error_log(skb, state, "truncated packet");
729 return true;
730 }
731
732
733
734
735
736
737 if (state->net->ct.sysctl_checksum &&
738 state->hook == NF_INET_PRE_ROUTING &&
739 nf_checksum(skb, state->hook, dataoff, IPPROTO_TCP, state->pf)) {
740 tcp_error_log(skb, state, "bad checksum");
741 return true;
742 }
743
744
745 tcpflags = (tcp_flag_byte(th) & ~(TCPHDR_ECE|TCPHDR_CWR|TCPHDR_PSH));
746 if (!tcp_valid_flags[tcpflags]) {
747 tcp_error_log(skb, state, "invalid tcp flag combination");
748 return true;
749 }
750
751 return false;
752}
753
754static noinline bool tcp_new(struct nf_conn *ct, const struct sk_buff *skb,
755 unsigned int dataoff,
756 const struct tcphdr *th)
757{
758 enum tcp_conntrack new_state;
759 struct net *net = nf_ct_net(ct);
760 const struct nf_tcp_net *tn = nf_tcp_pernet(net);
761 const struct ip_ct_tcp_state *sender = &ct->proto.tcp.seen[0];
762 const struct ip_ct_tcp_state *receiver = &ct->proto.tcp.seen[1];
763
764
765 new_state = tcp_conntracks[0][get_conntrack_index(th)][TCP_CONNTRACK_NONE];
766
767
768 if (new_state >= TCP_CONNTRACK_MAX) {
769 pr_debug("nf_ct_tcp: invalid new deleting.\n");
770 return false;
771 }
772
773 if (new_state == TCP_CONNTRACK_SYN_SENT) {
774 memset(&ct->proto.tcp, 0, sizeof(ct->proto.tcp));
775
776 ct->proto.tcp.seen[0].td_end =
777 segment_seq_plus_len(ntohl(th->seq), skb->len,
778 dataoff, th);
779 ct->proto.tcp.seen[0].td_maxwin = ntohs(th->window);
780 if (ct->proto.tcp.seen[0].td_maxwin == 0)
781 ct->proto.tcp.seen[0].td_maxwin = 1;
782 ct->proto.tcp.seen[0].td_maxend =
783 ct->proto.tcp.seen[0].td_end;
784
785 tcp_options(skb, dataoff, th, &ct->proto.tcp.seen[0]);
786 } else if (tn->tcp_loose == 0) {
787
788 return false;
789 } else {
790 memset(&ct->proto.tcp, 0, sizeof(ct->proto.tcp));
791
792
793
794
795
796 ct->proto.tcp.seen[0].td_end =
797 segment_seq_plus_len(ntohl(th->seq), skb->len,
798 dataoff, th);
799 ct->proto.tcp.seen[0].td_maxwin = ntohs(th->window);
800 if (ct->proto.tcp.seen[0].td_maxwin == 0)
801 ct->proto.tcp.seen[0].td_maxwin = 1;
802 ct->proto.tcp.seen[0].td_maxend =
803 ct->proto.tcp.seen[0].td_end +
804 ct->proto.tcp.seen[0].td_maxwin;
805
806
807
808 ct->proto.tcp.seen[0].flags =
809 ct->proto.tcp.seen[1].flags = IP_CT_TCP_FLAG_SACK_PERM |
810 IP_CT_TCP_FLAG_BE_LIBERAL;
811 }
812
813
814 ct->proto.tcp.last_index = TCP_NONE_SET;
815
816 pr_debug("%s: sender end=%u maxend=%u maxwin=%u scale=%i "
817 "receiver end=%u maxend=%u maxwin=%u scale=%i\n",
818 __func__,
819 sender->td_end, sender->td_maxend, sender->td_maxwin,
820 sender->td_scale,
821 receiver->td_end, receiver->td_maxend, receiver->td_maxwin,
822 receiver->td_scale);
823 return true;
824}
825
826static bool tcp_can_early_drop(const struct nf_conn *ct)
827{
828 switch (ct->proto.tcp.state) {
829 case TCP_CONNTRACK_FIN_WAIT:
830 case TCP_CONNTRACK_LAST_ACK:
831 case TCP_CONNTRACK_TIME_WAIT:
832 case TCP_CONNTRACK_CLOSE:
833 case TCP_CONNTRACK_CLOSE_WAIT:
834 return true;
835 default:
836 break;
837 }
838
839 return false;
840}
841
842
843int nf_conntrack_tcp_packet(struct nf_conn *ct,
844 struct sk_buff *skb,
845 unsigned int dataoff,
846 enum ip_conntrack_info ctinfo,
847 const struct nf_hook_state *state)
848{
849 struct net *net = nf_ct_net(ct);
850 struct nf_tcp_net *tn = nf_tcp_pernet(net);
851 struct nf_conntrack_tuple *tuple;
852 enum tcp_conntrack new_state, old_state;
853 unsigned int index, *timeouts;
854 enum ip_conntrack_dir dir;
855 const struct tcphdr *th;
856 struct tcphdr _tcph;
857 unsigned long timeout;
858
859 th = skb_header_pointer(skb, dataoff, sizeof(_tcph), &_tcph);
860 if (th == NULL)
861 return -NF_ACCEPT;
862
863 if (tcp_error(th, skb, dataoff, state))
864 return -NF_ACCEPT;
865
866 if (!nf_ct_is_confirmed(ct) && !tcp_new(ct, skb, dataoff, th))
867 return -NF_ACCEPT;
868
869 spin_lock_bh(&ct->lock);
870 old_state = ct->proto.tcp.state;
871 dir = CTINFO2DIR(ctinfo);
872 index = get_conntrack_index(th);
873 new_state = tcp_conntracks[dir][index][old_state];
874 tuple = &ct->tuplehash[dir].tuple;
875
876 switch (new_state) {
877 case TCP_CONNTRACK_SYN_SENT:
878 if (old_state < TCP_CONNTRACK_TIME_WAIT)
879 break;
880
881
882
883
884
885
886
887
888
889
890
891
892 if (((ct->proto.tcp.seen[dir].flags
893 | ct->proto.tcp.seen[!dir].flags)
894 & IP_CT_TCP_FLAG_CLOSE_INIT)
895 || (ct->proto.tcp.last_dir == dir
896 && ct->proto.tcp.last_index == TCP_RST_SET)) {
897
898
899 spin_unlock_bh(&ct->lock);
900
901
902
903
904
905 if (nf_ct_kill(ct))
906 return -NF_REPEAT;
907 return NF_DROP;
908 }
909 fallthrough;
910 case TCP_CONNTRACK_IGNORE:
911
912
913
914
915
916
917
918
919
920
921
922
923
924 if (index == TCP_SYNACK_SET
925 && ct->proto.tcp.last_index == TCP_SYN_SET
926 && ct->proto.tcp.last_dir != dir
927 && ntohl(th->ack_seq) == ct->proto.tcp.last_end) {
928
929
930
931
932
933
934 old_state = TCP_CONNTRACK_SYN_SENT;
935 new_state = TCP_CONNTRACK_SYN_RECV;
936 ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_end =
937 ct->proto.tcp.last_end;
938 ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_maxend =
939 ct->proto.tcp.last_end;
940 ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_maxwin =
941 ct->proto.tcp.last_win == 0 ?
942 1 : ct->proto.tcp.last_win;
943 ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_scale =
944 ct->proto.tcp.last_wscale;
945 ct->proto.tcp.last_flags &= ~IP_CT_EXP_CHALLENGE_ACK;
946 ct->proto.tcp.seen[ct->proto.tcp.last_dir].flags =
947 ct->proto.tcp.last_flags;
948 memset(&ct->proto.tcp.seen[dir], 0,
949 sizeof(struct ip_ct_tcp_state));
950 break;
951 }
952 ct->proto.tcp.last_index = index;
953 ct->proto.tcp.last_dir = dir;
954 ct->proto.tcp.last_seq = ntohl(th->seq);
955 ct->proto.tcp.last_end =
956 segment_seq_plus_len(ntohl(th->seq), skb->len, dataoff, th);
957 ct->proto.tcp.last_win = ntohs(th->window);
958
959
960
961
962
963
964
965
966 if (index == TCP_SYN_SET && dir == IP_CT_DIR_ORIGINAL) {
967 struct ip_ct_tcp_state seen = {};
968
969 ct->proto.tcp.last_flags =
970 ct->proto.tcp.last_wscale = 0;
971 tcp_options(skb, dataoff, th, &seen);
972 if (seen.flags & IP_CT_TCP_FLAG_WINDOW_SCALE) {
973 ct->proto.tcp.last_flags |=
974 IP_CT_TCP_FLAG_WINDOW_SCALE;
975 ct->proto.tcp.last_wscale = seen.td_scale;
976 }
977 if (seen.flags & IP_CT_TCP_FLAG_SACK_PERM) {
978 ct->proto.tcp.last_flags |=
979 IP_CT_TCP_FLAG_SACK_PERM;
980 }
981
982
983
984
985 if (old_state == TCP_CONNTRACK_LAST_ACK)
986 ct->proto.tcp.last_flags |=
987 IP_CT_EXP_CHALLENGE_ACK;
988 }
989 spin_unlock_bh(&ct->lock);
990 nf_ct_l4proto_log_invalid(skb, ct, state,
991 "packet (index %d) in dir %d ignored, state %s",
992 index, dir,
993 tcp_conntrack_names[old_state]);
994 return NF_ACCEPT;
995 case TCP_CONNTRACK_MAX:
996
997
998
999
1000
1001
1002 if (nfct_synproxy(ct) && old_state == TCP_CONNTRACK_SYN_SENT &&
1003 index == TCP_ACK_SET && dir == IP_CT_DIR_ORIGINAL &&
1004 ct->proto.tcp.last_dir == IP_CT_DIR_ORIGINAL &&
1005 ct->proto.tcp.seen[dir].td_end - 1 == ntohl(th->seq)) {
1006 pr_debug("nf_ct_tcp: SYN proxy client keep alive\n");
1007 spin_unlock_bh(&ct->lock);
1008 return NF_ACCEPT;
1009 }
1010
1011
1012 pr_debug("nf_ct_tcp: Invalid dir=%i index=%u ostate=%u\n",
1013 dir, get_conntrack_index(th), old_state);
1014 spin_unlock_bh(&ct->lock);
1015 nf_ct_l4proto_log_invalid(skb, ct, state, "invalid state");
1016 return -NF_ACCEPT;
1017 case TCP_CONNTRACK_TIME_WAIT:
1018
1019
1020
1021
1022 if (old_state == TCP_CONNTRACK_LAST_ACK &&
1023 index == TCP_ACK_SET &&
1024 ct->proto.tcp.last_dir != dir &&
1025 ct->proto.tcp.last_index == TCP_SYN_SET &&
1026 (ct->proto.tcp.last_flags & IP_CT_EXP_CHALLENGE_ACK)) {
1027
1028 ct->proto.tcp.last_flags &= ~IP_CT_EXP_CHALLENGE_ACK;
1029 spin_unlock_bh(&ct->lock);
1030 nf_ct_l4proto_log_invalid(skb, ct, state, "challenge-ack ignored");
1031 return NF_ACCEPT;
1032 }
1033 break;
1034 case TCP_CONNTRACK_SYN_SENT2:
1035
1036
1037
1038 ct->proto.tcp.last_flags |= IP_CT_TCP_SIMULTANEOUS_OPEN;
1039 break;
1040 case TCP_CONNTRACK_SYN_RECV:
1041 if (dir == IP_CT_DIR_REPLY && index == TCP_ACK_SET &&
1042 ct->proto.tcp.last_flags & IP_CT_TCP_SIMULTANEOUS_OPEN)
1043 new_state = TCP_CONNTRACK_ESTABLISHED;
1044 break;
1045 case TCP_CONNTRACK_CLOSE:
1046 if (index != TCP_RST_SET)
1047 break;
1048
1049
1050
1051
1052
1053
1054
1055
1056 if (tcp_can_early_drop(ct))
1057 goto in_window;
1058
1059
1060 if ((ct->proto.tcp.seen[!dir].flags & IP_CT_TCP_FLAG_MAXACK_SET) &&
1061 ct->proto.tcp.last_index != TCP_SYN_SET) {
1062 u32 seq = ntohl(th->seq);
1063
1064
1065
1066
1067
1068 if (seq == 0 && !nf_conntrack_tcp_established(ct))
1069 break;
1070
1071 if (before(seq, ct->proto.tcp.seen[!dir].td_maxack) &&
1072 !tn->tcp_ignore_invalid_rst) {
1073
1074 spin_unlock_bh(&ct->lock);
1075 nf_ct_l4proto_log_invalid(skb, ct, state, "invalid rst");
1076 return -NF_ACCEPT;
1077 }
1078
1079 if (!nf_conntrack_tcp_established(ct) ||
1080 seq == ct->proto.tcp.seen[!dir].td_maxack)
1081 break;
1082
1083
1084
1085
1086
1087 if (ct->proto.tcp.last_index == TCP_ACK_SET &&
1088 ct->proto.tcp.last_dir == dir &&
1089 seq == ct->proto.tcp.last_end)
1090 break;
1091
1092
1093
1094
1095 new_state = old_state;
1096 }
1097 if (((test_bit(IPS_SEEN_REPLY_BIT, &ct->status)
1098 && ct->proto.tcp.last_index == TCP_SYN_SET)
1099 || (!test_bit(IPS_ASSURED_BIT, &ct->status)
1100 && ct->proto.tcp.last_index == TCP_ACK_SET))
1101 && ntohl(th->ack_seq) == ct->proto.tcp.last_end) {
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111 goto in_window;
1112 }
1113 break;
1114 default:
1115
1116 break;
1117 }
1118
1119 if (!tcp_in_window(ct, dir, index,
1120 skb, dataoff, th, state)) {
1121 spin_unlock_bh(&ct->lock);
1122 return -NF_ACCEPT;
1123 }
1124 in_window:
1125
1126 ct->proto.tcp.last_index = index;
1127 ct->proto.tcp.last_dir = dir;
1128
1129 pr_debug("tcp_conntracks: ");
1130 nf_ct_dump_tuple(tuple);
1131 pr_debug("syn=%i ack=%i fin=%i rst=%i old=%i new=%i\n",
1132 (th->syn ? 1 : 0), (th->ack ? 1 : 0),
1133 (th->fin ? 1 : 0), (th->rst ? 1 : 0),
1134 old_state, new_state);
1135
1136 ct->proto.tcp.state = new_state;
1137 if (old_state != new_state
1138 && new_state == TCP_CONNTRACK_FIN_WAIT)
1139 ct->proto.tcp.seen[dir].flags |= IP_CT_TCP_FLAG_CLOSE_INIT;
1140
1141 timeouts = nf_ct_timeout_lookup(ct);
1142 if (!timeouts)
1143 timeouts = tn->timeouts;
1144
1145 if (ct->proto.tcp.retrans >= tn->tcp_max_retrans &&
1146 timeouts[new_state] > timeouts[TCP_CONNTRACK_RETRANS])
1147 timeout = timeouts[TCP_CONNTRACK_RETRANS];
1148 else if (unlikely(index == TCP_RST_SET))
1149 timeout = timeouts[TCP_CONNTRACK_CLOSE];
1150 else if ((ct->proto.tcp.seen[0].flags | ct->proto.tcp.seen[1].flags) &
1151 IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED &&
1152 timeouts[new_state] > timeouts[TCP_CONNTRACK_UNACK])
1153 timeout = timeouts[TCP_CONNTRACK_UNACK];
1154 else if (ct->proto.tcp.last_win == 0 &&
1155 timeouts[new_state] > timeouts[TCP_CONNTRACK_RETRANS])
1156 timeout = timeouts[TCP_CONNTRACK_RETRANS];
1157 else
1158 timeout = timeouts[new_state];
1159 spin_unlock_bh(&ct->lock);
1160
1161 if (new_state != old_state)
1162 nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
1163
1164 if (!test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
1165
1166
1167
1168
1169 if (th->rst) {
1170 nf_ct_kill_acct(ct, ctinfo, skb);
1171 return NF_ACCEPT;
1172 }
1173
1174 if (index == TCP_SYN_SET && old_state == TCP_CONNTRACK_SYN_SENT) {
1175
1176
1177
1178
1179
1180 return NF_ACCEPT;
1181 }
1182
1183
1184
1185
1186 if (new_state == TCP_CONNTRACK_ESTABLISHED &&
1187 timeout > timeouts[TCP_CONNTRACK_UNACK])
1188 timeout = timeouts[TCP_CONNTRACK_UNACK];
1189 } else if (!test_bit(IPS_ASSURED_BIT, &ct->status)
1190 && (old_state == TCP_CONNTRACK_SYN_RECV
1191 || old_state == TCP_CONNTRACK_ESTABLISHED)
1192 && new_state == TCP_CONNTRACK_ESTABLISHED) {
1193
1194
1195
1196 set_bit(IPS_ASSURED_BIT, &ct->status);
1197 nf_conntrack_event_cache(IPCT_ASSURED, ct);
1198 }
1199 nf_ct_refresh_acct(ct, ctinfo, skb, timeout);
1200
1201 return NF_ACCEPT;
1202}
1203
1204#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
1205
1206#include <linux/netfilter/nfnetlink.h>
1207#include <linux/netfilter/nfnetlink_conntrack.h>
1208
1209static int tcp_to_nlattr(struct sk_buff *skb, struct nlattr *nla,
1210 struct nf_conn *ct, bool destroy)
1211{
1212 struct nlattr *nest_parms;
1213 struct nf_ct_tcp_flags tmp = {};
1214
1215 spin_lock_bh(&ct->lock);
1216 nest_parms = nla_nest_start(skb, CTA_PROTOINFO_TCP);
1217 if (!nest_parms)
1218 goto nla_put_failure;
1219
1220 if (nla_put_u8(skb, CTA_PROTOINFO_TCP_STATE, ct->proto.tcp.state))
1221 goto nla_put_failure;
1222
1223 if (destroy)
1224 goto skip_state;
1225
1226 if (nla_put_u8(skb, CTA_PROTOINFO_TCP_WSCALE_ORIGINAL,
1227 ct->proto.tcp.seen[0].td_scale) ||
1228 nla_put_u8(skb, CTA_PROTOINFO_TCP_WSCALE_REPLY,
1229 ct->proto.tcp.seen[1].td_scale))
1230 goto nla_put_failure;
1231
1232 tmp.flags = ct->proto.tcp.seen[0].flags;
1233 if (nla_put(skb, CTA_PROTOINFO_TCP_FLAGS_ORIGINAL,
1234 sizeof(struct nf_ct_tcp_flags), &tmp))
1235 goto nla_put_failure;
1236
1237 tmp.flags = ct->proto.tcp.seen[1].flags;
1238 if (nla_put(skb, CTA_PROTOINFO_TCP_FLAGS_REPLY,
1239 sizeof(struct nf_ct_tcp_flags), &tmp))
1240 goto nla_put_failure;
1241skip_state:
1242 spin_unlock_bh(&ct->lock);
1243 nla_nest_end(skb, nest_parms);
1244
1245 return 0;
1246
1247nla_put_failure:
1248 spin_unlock_bh(&ct->lock);
1249 return -1;
1250}
1251
1252static const struct nla_policy tcp_nla_policy[CTA_PROTOINFO_TCP_MAX+1] = {
1253 [CTA_PROTOINFO_TCP_STATE] = { .type = NLA_U8 },
1254 [CTA_PROTOINFO_TCP_WSCALE_ORIGINAL] = { .type = NLA_U8 },
1255 [CTA_PROTOINFO_TCP_WSCALE_REPLY] = { .type = NLA_U8 },
1256 [CTA_PROTOINFO_TCP_FLAGS_ORIGINAL] = { .len = sizeof(struct nf_ct_tcp_flags) },
1257 [CTA_PROTOINFO_TCP_FLAGS_REPLY] = { .len = sizeof(struct nf_ct_tcp_flags) },
1258};
1259
1260#define TCP_NLATTR_SIZE ( \
1261 NLA_ALIGN(NLA_HDRLEN + 1) + \
1262 NLA_ALIGN(NLA_HDRLEN + 1) + \
1263 NLA_ALIGN(NLA_HDRLEN + sizeof(struct nf_ct_tcp_flags)) + \
1264 NLA_ALIGN(NLA_HDRLEN + sizeof(struct nf_ct_tcp_flags)))
1265
1266static int nlattr_to_tcp(struct nlattr *cda[], struct nf_conn *ct)
1267{
1268 struct nlattr *pattr = cda[CTA_PROTOINFO_TCP];
1269 struct nlattr *tb[CTA_PROTOINFO_TCP_MAX+1];
1270 int err;
1271
1272
1273
1274 if (!pattr)
1275 return 0;
1276
1277 err = nla_parse_nested_deprecated(tb, CTA_PROTOINFO_TCP_MAX, pattr,
1278 tcp_nla_policy, NULL);
1279 if (err < 0)
1280 return err;
1281
1282 if (tb[CTA_PROTOINFO_TCP_STATE] &&
1283 nla_get_u8(tb[CTA_PROTOINFO_TCP_STATE]) >= TCP_CONNTRACK_MAX)
1284 return -EINVAL;
1285
1286 spin_lock_bh(&ct->lock);
1287 if (tb[CTA_PROTOINFO_TCP_STATE])
1288 ct->proto.tcp.state = nla_get_u8(tb[CTA_PROTOINFO_TCP_STATE]);
1289
1290 if (tb[CTA_PROTOINFO_TCP_FLAGS_ORIGINAL]) {
1291 struct nf_ct_tcp_flags *attr =
1292 nla_data(tb[CTA_PROTOINFO_TCP_FLAGS_ORIGINAL]);
1293 ct->proto.tcp.seen[0].flags &= ~attr->mask;
1294 ct->proto.tcp.seen[0].flags |= attr->flags & attr->mask;
1295 }
1296
1297 if (tb[CTA_PROTOINFO_TCP_FLAGS_REPLY]) {
1298 struct nf_ct_tcp_flags *attr =
1299 nla_data(tb[CTA_PROTOINFO_TCP_FLAGS_REPLY]);
1300 ct->proto.tcp.seen[1].flags &= ~attr->mask;
1301 ct->proto.tcp.seen[1].flags |= attr->flags & attr->mask;
1302 }
1303
1304 if (tb[CTA_PROTOINFO_TCP_WSCALE_ORIGINAL] &&
1305 tb[CTA_PROTOINFO_TCP_WSCALE_REPLY] &&
1306 ct->proto.tcp.seen[0].flags & IP_CT_TCP_FLAG_WINDOW_SCALE &&
1307 ct->proto.tcp.seen[1].flags & IP_CT_TCP_FLAG_WINDOW_SCALE) {
1308 ct->proto.tcp.seen[0].td_scale =
1309 nla_get_u8(tb[CTA_PROTOINFO_TCP_WSCALE_ORIGINAL]);
1310 ct->proto.tcp.seen[1].td_scale =
1311 nla_get_u8(tb[CTA_PROTOINFO_TCP_WSCALE_REPLY]);
1312 }
1313 spin_unlock_bh(&ct->lock);
1314
1315 return 0;
1316}
1317
1318static unsigned int tcp_nlattr_tuple_size(void)
1319{
1320 static unsigned int size __read_mostly;
1321
1322 if (!size)
1323 size = nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1);
1324
1325 return size;
1326}
1327#endif
1328
1329#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1330
1331#include <linux/netfilter/nfnetlink.h>
1332#include <linux/netfilter/nfnetlink_cttimeout.h>
1333
1334static int tcp_timeout_nlattr_to_obj(struct nlattr *tb[],
1335 struct net *net, void *data)
1336{
1337 struct nf_tcp_net *tn = nf_tcp_pernet(net);
1338 unsigned int *timeouts = data;
1339 int i;
1340
1341 if (!timeouts)
1342 timeouts = tn->timeouts;
1343
1344 for (i=0; i<TCP_CONNTRACK_TIMEOUT_MAX; i++)
1345 timeouts[i] = tn->timeouts[i];
1346
1347 if (tb[CTA_TIMEOUT_TCP_SYN_SENT]) {
1348 timeouts[TCP_CONNTRACK_SYN_SENT] =
1349 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_SYN_SENT]))*HZ;
1350 }
1351
1352 if (tb[CTA_TIMEOUT_TCP_SYN_RECV]) {
1353 timeouts[TCP_CONNTRACK_SYN_RECV] =
1354 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_SYN_RECV]))*HZ;
1355 }
1356 if (tb[CTA_TIMEOUT_TCP_ESTABLISHED]) {
1357 timeouts[TCP_CONNTRACK_ESTABLISHED] =
1358 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_ESTABLISHED]))*HZ;
1359 }
1360 if (tb[CTA_TIMEOUT_TCP_FIN_WAIT]) {
1361 timeouts[TCP_CONNTRACK_FIN_WAIT] =
1362 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_FIN_WAIT]))*HZ;
1363 }
1364 if (tb[CTA_TIMEOUT_TCP_CLOSE_WAIT]) {
1365 timeouts[TCP_CONNTRACK_CLOSE_WAIT] =
1366 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_CLOSE_WAIT]))*HZ;
1367 }
1368 if (tb[CTA_TIMEOUT_TCP_LAST_ACK]) {
1369 timeouts[TCP_CONNTRACK_LAST_ACK] =
1370 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_LAST_ACK]))*HZ;
1371 }
1372 if (tb[CTA_TIMEOUT_TCP_TIME_WAIT]) {
1373 timeouts[TCP_CONNTRACK_TIME_WAIT] =
1374 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_TIME_WAIT]))*HZ;
1375 }
1376 if (tb[CTA_TIMEOUT_TCP_CLOSE]) {
1377 timeouts[TCP_CONNTRACK_CLOSE] =
1378 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_CLOSE]))*HZ;
1379 }
1380 if (tb[CTA_TIMEOUT_TCP_SYN_SENT2]) {
1381 timeouts[TCP_CONNTRACK_SYN_SENT2] =
1382 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_SYN_SENT2]))*HZ;
1383 }
1384 if (tb[CTA_TIMEOUT_TCP_RETRANS]) {
1385 timeouts[TCP_CONNTRACK_RETRANS] =
1386 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_RETRANS]))*HZ;
1387 }
1388 if (tb[CTA_TIMEOUT_TCP_UNACK]) {
1389 timeouts[TCP_CONNTRACK_UNACK] =
1390 ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_UNACK]))*HZ;
1391 }
1392
1393 timeouts[CTA_TIMEOUT_TCP_UNSPEC] = timeouts[CTA_TIMEOUT_TCP_SYN_SENT];
1394 return 0;
1395}
1396
1397static int
1398tcp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
1399{
1400 const unsigned int *timeouts = data;
1401
1402 if (nla_put_be32(skb, CTA_TIMEOUT_TCP_SYN_SENT,
1403 htonl(timeouts[TCP_CONNTRACK_SYN_SENT] / HZ)) ||
1404 nla_put_be32(skb, CTA_TIMEOUT_TCP_SYN_RECV,
1405 htonl(timeouts[TCP_CONNTRACK_SYN_RECV] / HZ)) ||
1406 nla_put_be32(skb, CTA_TIMEOUT_TCP_ESTABLISHED,
1407 htonl(timeouts[TCP_CONNTRACK_ESTABLISHED] / HZ)) ||
1408 nla_put_be32(skb, CTA_TIMEOUT_TCP_FIN_WAIT,
1409 htonl(timeouts[TCP_CONNTRACK_FIN_WAIT] / HZ)) ||
1410 nla_put_be32(skb, CTA_TIMEOUT_TCP_CLOSE_WAIT,
1411 htonl(timeouts[TCP_CONNTRACK_CLOSE_WAIT] / HZ)) ||
1412 nla_put_be32(skb, CTA_TIMEOUT_TCP_LAST_ACK,
1413 htonl(timeouts[TCP_CONNTRACK_LAST_ACK] / HZ)) ||
1414 nla_put_be32(skb, CTA_TIMEOUT_TCP_TIME_WAIT,
1415 htonl(timeouts[TCP_CONNTRACK_TIME_WAIT] / HZ)) ||
1416 nla_put_be32(skb, CTA_TIMEOUT_TCP_CLOSE,
1417 htonl(timeouts[TCP_CONNTRACK_CLOSE] / HZ)) ||
1418 nla_put_be32(skb, CTA_TIMEOUT_TCP_SYN_SENT2,
1419 htonl(timeouts[TCP_CONNTRACK_SYN_SENT2] / HZ)) ||
1420 nla_put_be32(skb, CTA_TIMEOUT_TCP_RETRANS,
1421 htonl(timeouts[TCP_CONNTRACK_RETRANS] / HZ)) ||
1422 nla_put_be32(skb, CTA_TIMEOUT_TCP_UNACK,
1423 htonl(timeouts[TCP_CONNTRACK_UNACK] / HZ)))
1424 goto nla_put_failure;
1425 return 0;
1426
1427nla_put_failure:
1428 return -ENOSPC;
1429}
1430
1431static const struct nla_policy tcp_timeout_nla_policy[CTA_TIMEOUT_TCP_MAX+1] = {
1432 [CTA_TIMEOUT_TCP_SYN_SENT] = { .type = NLA_U32 },
1433 [CTA_TIMEOUT_TCP_SYN_RECV] = { .type = NLA_U32 },
1434 [CTA_TIMEOUT_TCP_ESTABLISHED] = { .type = NLA_U32 },
1435 [CTA_TIMEOUT_TCP_FIN_WAIT] = { .type = NLA_U32 },
1436 [CTA_TIMEOUT_TCP_CLOSE_WAIT] = { .type = NLA_U32 },
1437 [CTA_TIMEOUT_TCP_LAST_ACK] = { .type = NLA_U32 },
1438 [CTA_TIMEOUT_TCP_TIME_WAIT] = { .type = NLA_U32 },
1439 [CTA_TIMEOUT_TCP_CLOSE] = { .type = NLA_U32 },
1440 [CTA_TIMEOUT_TCP_SYN_SENT2] = { .type = NLA_U32 },
1441 [CTA_TIMEOUT_TCP_RETRANS] = { .type = NLA_U32 },
1442 [CTA_TIMEOUT_TCP_UNACK] = { .type = NLA_U32 },
1443};
1444#endif
1445
1446void nf_conntrack_tcp_init_net(struct net *net)
1447{
1448 struct nf_tcp_net *tn = nf_tcp_pernet(net);
1449 int i;
1450
1451 for (i = 0; i < TCP_CONNTRACK_TIMEOUT_MAX; i++)
1452 tn->timeouts[i] = tcp_timeouts[i];
1453
1454
1455
1456
1457 tn->timeouts[0] = tcp_timeouts[TCP_CONNTRACK_SYN_SENT];
1458
1459
1460
1461
1462 tn->tcp_loose = 1;
1463
1464
1465
1466
1467
1468 tn->tcp_be_liberal = 0;
1469
1470
1471 tn->tcp_ignore_invalid_rst = 0;
1472
1473
1474
1475
1476
1477 tn->tcp_max_retrans = 3;
1478
1479#if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
1480 tn->offload_timeout = 30 * HZ;
1481#endif
1482}
1483
1484const struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp =
1485{
1486 .l4proto = IPPROTO_TCP,
1487#ifdef CONFIG_NF_CONNTRACK_PROCFS
1488 .print_conntrack = tcp_print_conntrack,
1489#endif
1490 .can_early_drop = tcp_can_early_drop,
1491#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
1492 .to_nlattr = tcp_to_nlattr,
1493 .from_nlattr = nlattr_to_tcp,
1494 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
1495 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
1496 .nlattr_tuple_size = tcp_nlattr_tuple_size,
1497 .nlattr_size = TCP_NLATTR_SIZE,
1498 .nla_policy = nf_ct_port_nla_policy,
1499#endif
1500#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1501 .ctnl_timeout = {
1502 .nlattr_to_obj = tcp_timeout_nlattr_to_obj,
1503 .obj_to_nlattr = tcp_timeout_obj_to_nlattr,
1504 .nlattr_max = CTA_TIMEOUT_TCP_MAX,
1505 .obj_size = sizeof(unsigned int) *
1506 TCP_CONNTRACK_TIMEOUT_MAX,
1507 .nla_policy = tcp_timeout_nla_policy,
1508 },
1509#endif
1510};
1511