3 * Linux INET6 implementation
6 * Pedro Roque <roque@di.fc.ul.pt>
8 * $Id: tcp_ipv6.c,v 1.144 2002/02/01 22:01:04 davem Exp $
11 * linux/net/ipv4/tcp.c
12 * linux/net/ipv4/tcp_input.c
13 * linux/net/ipv4/tcp_output.c
16 * Hideaki YOSHIFUJI : sin6_scope_id support
17 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
18 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
19 * a single port at the same time.
20 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/tcp6 to seq_file.
22 * This program is free software; you can redistribute it and/or
23 * modify it under the terms of the GNU General Public License
24 * as published by the Free Software Foundation; either version
25 * 2 of the License, or (at your option) any later version.
28 #include <linux/module.h>
29 #include <linux/config.h>
30 #include <linux/errno.h>
31 #include <linux/types.h>
32 #include <linux/socket.h>
33 #include <linux/sockios.h>
34 #include <linux/net.h>
35 #include <linux/jiffies.h>
37 #include <linux/in6.h>
38 #include <linux/netdevice.h>
39 #include <linux/init.h>
40 #include <linux/jhash.h>
41 #include <linux/ipsec.h>
42 #include <linux/times.h>
44 #include <linux/ipv6.h>
45 #include <linux/icmpv6.h>
46 #include <linux/random.h>
49 #include <net/ndisc.h>
51 #include <net/transp_v6.h>
52 #include <net/addrconf.h>
53 #include <net/ip6_route.h>
54 #include <net/ip6_checksum.h>
55 #include <net/inet_ecn.h>
56 #include <net/protocol.h>
58 #include <net/addrconf.h>
61 #include <asm/uaccess.h>
63 #include <linux/proc_fs.h>
64 #include <linux/seq_file.h>
66 static void tcp_v6_send_reset(struct sk_buff *skb);
67 static void tcp_v6_or_send_ack(struct sk_buff *skb, struct open_request *req);
68 static void tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len,
71 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
72 static int tcp_v6_xmit(struct sk_buff *skb, int ipfragok);
74 static struct tcp_func ipv6_mapped;
75 static struct tcp_func ipv6_specific;
77 /* I have no idea if this is a good hash for v6 or not. -DaveM */
78 static __inline__ int tcp_v6_hashfn(struct in6_addr *laddr, u16 lport,
79 struct in6_addr *faddr, u16 fport)
81 int hashent = (lport ^ fport);
83 hashent ^= (laddr->s6_addr32[3] ^ faddr->s6_addr32[3]);
84 hashent ^= hashent>>16;
85 hashent ^= hashent>>8;
86 return (hashent & (tcp_ehash_size - 1));
89 static __inline__ int tcp_v6_sk_hashfn(struct sock *sk)
91 struct inet_opt *inet = inet_sk(sk);
92 struct ipv6_pinfo *np = inet6_sk(sk);
93 struct in6_addr *laddr = &np->rcv_saddr;
94 struct in6_addr *faddr = &np->daddr;
95 __u16 lport = inet->num;
96 __u16 fport = inet->dport;
97 return tcp_v6_hashfn(laddr, lport, faddr, fport);
100 static inline int tcp_v6_bind_conflict(struct sock *sk,
101 struct tcp_bind_bucket *tb)
104 struct hlist_node *node;
106 /* We must walk the whole port owner list in this case. -DaveM */
107 sk_for_each_bound(sk2, node, &tb->owners) {
109 (!sk->sk_bound_dev_if ||
110 !sk2->sk_bound_dev_if ||
111 sk->sk_bound_dev_if == sk2->sk_bound_dev_if) &&
112 (!sk->sk_reuse || !sk2->sk_reuse ||
113 sk2->sk_state == TCP_LISTEN) &&
114 ipv6_rcv_saddr_equal(sk, sk2))
121 /* Grrr, addr_type already calculated by caller, but I don't want
122 * to add some silly "cookie" argument to this method just for that.
123 * But it doesn't matter, the recalculation is in the rarest path
124 * this function ever takes.
126 static int tcp_v6_get_port(struct sock *sk, unsigned short snum)
128 struct tcp_bind_hashbucket *head;
129 struct tcp_bind_bucket *tb;
130 struct hlist_node *node;
135 int low = sysctl_local_port_range[0];
136 int high = sysctl_local_port_range[1];
137 int remaining = (high - low) + 1;
140 spin_lock(&tcp_portalloc_lock);
141 rover = tcp_port_rover;
143 if ((rover < low) || (rover > high))
145 head = &tcp_bhash[tcp_bhashfn(rover)];
146 spin_lock(&head->lock);
147 tb_for_each(tb, node, &head->chain)
148 if (tb->port == rover)
152 spin_unlock(&head->lock);
153 } while (--remaining > 0);
154 tcp_port_rover = rover;
155 spin_unlock(&tcp_portalloc_lock);
157 /* Exhausted local port range during search? */
162 /* OK, here is the one we will use. */
165 head = &tcp_bhash[tcp_bhashfn(snum)];
166 spin_lock(&head->lock);
167 tb_for_each(tb, node, &head->chain)
168 if (tb->port == snum)
174 if (tb && !hlist_empty(&tb->owners)) {
175 if (tb->fastreuse > 0 && sk->sk_reuse &&
176 sk->sk_state != TCP_LISTEN) {
180 if (tcp_v6_bind_conflict(sk, tb))
186 if (!tb && (tb = tcp_bucket_create(head, snum)) == NULL)
188 if (hlist_empty(&tb->owners)) {
189 if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
193 } else if (tb->fastreuse &&
194 (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
198 if (!tcp_sk(sk)->bind_hash)
199 tcp_bind_hash(sk, tb, snum);
200 BUG_TRAP(tcp_sk(sk)->bind_hash == tb);
204 spin_unlock(&head->lock);
210 static __inline__ void __tcp_v6_hash(struct sock *sk)
212 struct hlist_head *list;
215 BUG_TRAP(sk_unhashed(sk));
217 if (sk->sk_state == TCP_LISTEN) {
218 list = &tcp_listening_hash[tcp_sk_listen_hashfn(sk)];
219 lock = &tcp_lhash_lock;
222 sk->sk_hashent = tcp_v6_sk_hashfn(sk);
223 list = &tcp_ehash[sk->sk_hashent].chain;
224 lock = &tcp_ehash[sk->sk_hashent].lock;
228 __sk_add_node(sk, list);
229 sock_prot_inc_use(sk->sk_prot);
234 static void tcp_v6_hash(struct sock *sk)
236 if (sk->sk_state != TCP_CLOSE) {
237 struct tcp_opt *tp = tcp_sk(sk);
239 if (tp->af_specific == &ipv6_mapped) {
249 static struct sock *tcp_v6_lookup_listener(struct in6_addr *daddr, unsigned short hnum, int dif)
252 struct hlist_node *node;
253 struct sock *result = NULL;
257 read_lock(&tcp_lhash_lock);
258 sk_for_each(sk, node, &tcp_listening_hash[tcp_lhashfn(hnum)]) {
259 if (inet_sk(sk)->num == hnum && sk->sk_family == PF_INET6) {
260 struct ipv6_pinfo *np = inet6_sk(sk);
263 if (!ipv6_addr_any(&np->rcv_saddr)) {
264 if (ipv6_addr_cmp(&np->rcv_saddr, daddr))
268 if (sk->sk_bound_dev_if) {
269 if (sk->sk_bound_dev_if != dif)
277 if (score > hiscore) {
285 read_unlock(&tcp_lhash_lock);
289 /* Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
290 * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
292 * The sockhash lock must be held as a reader here.
295 static inline struct sock *__tcp_v6_lookup_established(struct in6_addr *saddr, u16 sport,
296 struct in6_addr *daddr, u16 hnum,
299 struct tcp_ehash_bucket *head;
301 struct hlist_node *node;
302 __u32 ports = TCP_COMBINED_PORTS(sport, hnum);
305 /* Optimize here for direct hit, only listening connections can
306 * have wildcards anyways.
308 hash = tcp_v6_hashfn(daddr, hnum, saddr, sport);
309 head = &tcp_ehash[hash];
310 read_lock(&head->lock);
311 sk_for_each(sk, node, &head->chain) {
312 /* For IPV6 do the cheaper port and family tests first. */
313 if(TCP_IPV6_MATCH(sk, saddr, daddr, ports, dif))
314 goto hit; /* You sunk my battleship! */
316 /* Must check for a TIME_WAIT'er before going to listener hash. */
317 sk_for_each(sk, node, &(head + tcp_ehash_size)->chain) {
318 /* FIXME: acme: check this... */
319 struct tcp_tw_bucket *tw = (struct tcp_tw_bucket *)sk;
321 if(*((__u32 *)&(tw->tw_dport)) == ports &&
322 sk->sk_family == PF_INET6) {
323 if(!ipv6_addr_cmp(&tw->tw_v6_daddr, saddr) &&
324 !ipv6_addr_cmp(&tw->tw_v6_rcv_saddr, daddr) &&
325 (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif))
329 read_unlock(&head->lock);
334 read_unlock(&head->lock);
339 static inline struct sock *__tcp_v6_lookup(struct in6_addr *saddr, u16 sport,
340 struct in6_addr *daddr, u16 hnum,
345 sk = __tcp_v6_lookup_established(saddr, sport, daddr, hnum, dif);
350 return tcp_v6_lookup_listener(daddr, hnum, dif);
353 inline struct sock *tcp_v6_lookup(struct in6_addr *saddr, u16 sport,
354 struct in6_addr *daddr, u16 dport,
360 sk = __tcp_v6_lookup(saddr, sport, daddr, ntohs(dport), dif);
368 * Open request hash tables.
371 static u32 tcp_v6_synq_hash(struct in6_addr *raddr, u16 rport, u32 rnd)
375 a = raddr->s6_addr32[0];
376 b = raddr->s6_addr32[1];
377 c = raddr->s6_addr32[2];
379 a += JHASH_GOLDEN_RATIO;
380 b += JHASH_GOLDEN_RATIO;
382 __jhash_mix(a, b, c);
384 a += raddr->s6_addr32[3];
386 __jhash_mix(a, b, c);
388 return c & (TCP_SYNQ_HSIZE - 1);
391 static struct open_request *tcp_v6_search_req(struct tcp_opt *tp,
392 struct open_request ***prevp,
394 struct in6_addr *raddr,
395 struct in6_addr *laddr,
398 struct tcp_listen_opt *lopt = tp->listen_opt;
399 struct open_request *req, **prev;
401 for (prev = &lopt->syn_table[tcp_v6_synq_hash(raddr, rport, lopt->hash_rnd)];
402 (req = *prev) != NULL;
403 prev = &req->dl_next) {
404 if (req->rmt_port == rport &&
405 req->class->family == AF_INET6 &&
406 !ipv6_addr_cmp(&req->af.v6_req.rmt_addr, raddr) &&
407 !ipv6_addr_cmp(&req->af.v6_req.loc_addr, laddr) &&
408 (!req->af.v6_req.iif || req->af.v6_req.iif == iif)) {
409 BUG_TRAP(req->sk == NULL);
418 static __inline__ u16 tcp_v6_check(struct tcphdr *th, int len,
419 struct in6_addr *saddr,
420 struct in6_addr *daddr,
423 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
426 static __u32 tcp_v6_init_sequence(struct sock *sk, struct sk_buff *skb)
428 if (skb->protocol == htons(ETH_P_IPV6)) {
429 return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32,
430 skb->nh.ipv6h->saddr.s6_addr32,
434 return secure_tcp_sequence_number(skb->nh.iph->daddr,
441 static int tcp_v6_check_established(struct sock *sk)
443 struct inet_opt *inet = inet_sk(sk);
444 struct ipv6_pinfo *np = inet6_sk(sk);
445 struct in6_addr *daddr = &np->rcv_saddr;
446 struct in6_addr *saddr = &np->daddr;
447 int dif = sk->sk_bound_dev_if;
448 u32 ports = TCP_COMBINED_PORTS(inet->dport, inet->num);
449 int hash = tcp_v6_hashfn(daddr, inet->num, saddr, inet->dport);
450 struct tcp_ehash_bucket *head = &tcp_ehash[hash];
452 struct hlist_node *node;
453 struct tcp_tw_bucket *tw;
455 write_lock_bh(&head->lock);
457 /* Check TIME-WAIT sockets first. */
458 sk_for_each(sk2, node, &(head + tcp_ehash_size)->chain) {
459 tw = (struct tcp_tw_bucket*)sk2;
461 if(*((__u32 *)&(tw->tw_dport)) == ports &&
462 sk2->sk_family == PF_INET6 &&
463 !ipv6_addr_cmp(&tw->tw_v6_daddr, saddr) &&
464 !ipv6_addr_cmp(&tw->tw_v6_rcv_saddr, daddr) &&
465 sk2->sk_bound_dev_if == sk->sk_bound_dev_if) {
466 struct tcp_opt *tp = tcp_sk(sk);
468 if (tw->tw_ts_recent_stamp) {
469 /* See comment in tcp_ipv4.c */
470 tp->write_seq = tw->tw_snd_nxt + 65535 + 2;
473 tp->ts_recent = tw->tw_ts_recent;
474 tp->ts_recent_stamp = tw->tw_ts_recent_stamp;
483 /* And established part... */
484 sk_for_each(sk2, node, &head->chain) {
485 if(TCP_IPV6_MATCH(sk2, saddr, daddr, ports, dif))
490 BUG_TRAP(sk_unhashed(sk));
491 __sk_add_node(sk, &head->chain);
492 sk->sk_hashent = hash;
493 sock_prot_inc_use(sk->sk_prot);
494 write_unlock_bh(&head->lock);
497 /* Silly. Should hash-dance instead... */
499 tcp_tw_deschedule(tw);
500 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
508 write_unlock_bh(&head->lock);
509 return -EADDRNOTAVAIL;
512 static int tcp_v6_hash_connect(struct sock *sk)
514 struct tcp_bind_hashbucket *head;
515 struct tcp_bind_bucket *tb;
518 if (inet_sk(sk)->num == 0) {
519 int err = tcp_v6_get_port(sk, inet_sk(sk)->num);
522 inet_sk(sk)->sport = htons(inet_sk(sk)->num);
525 head = &tcp_bhash[tcp_bhashfn(inet_sk(sk)->num)];
528 spin_lock_bh(&head->lock);
530 if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
532 spin_unlock_bh(&head->lock);
535 spin_unlock_bh(&head->lock);
536 return tcp_v6_check_established(sk);
540 static __inline__ int tcp_v6_iif(struct sk_buff *skb)
542 return IP6CB(skb)->iif;
545 static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
548 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
549 struct inet_opt *inet = inet_sk(sk);
550 struct ipv6_pinfo *np = inet6_sk(sk);
551 struct tcp_opt *tp = tcp_sk(sk);
552 struct in6_addr *saddr = NULL;
554 struct dst_entry *dst;
558 if (addr_len < SIN6_LEN_RFC2133)
561 if (usin->sin6_family != AF_INET6)
562 return(-EAFNOSUPPORT);
564 memset(&fl, 0, sizeof(fl));
567 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
568 IP6_ECN_flow_init(fl.fl6_flowlabel);
569 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
570 struct ip6_flowlabel *flowlabel;
571 flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
572 if (flowlabel == NULL)
574 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
575 fl6_sock_release(flowlabel);
580 * connect() to INADDR_ANY means loopback (BSD'ism).
583 if(ipv6_addr_any(&usin->sin6_addr))
584 usin->sin6_addr.s6_addr[15] = 0x1;
586 addr_type = ipv6_addr_type(&usin->sin6_addr);
588 if(addr_type & IPV6_ADDR_MULTICAST)
591 if (addr_type&IPV6_ADDR_LINKLOCAL) {
592 if (addr_len >= sizeof(struct sockaddr_in6) &&
593 usin->sin6_scope_id) {
594 /* If interface is set while binding, indices
597 if (sk->sk_bound_dev_if &&
598 sk->sk_bound_dev_if != usin->sin6_scope_id)
601 sk->sk_bound_dev_if = usin->sin6_scope_id;
604 /* Connect to link-local address requires an interface */
605 if (!sk->sk_bound_dev_if)
609 if (tp->ts_recent_stamp &&
610 ipv6_addr_cmp(&np->daddr, &usin->sin6_addr)) {
612 tp->ts_recent_stamp = 0;
616 ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
617 np->flow_label = fl.fl6_flowlabel;
623 if (addr_type == IPV6_ADDR_MAPPED) {
624 u32 exthdrlen = tp->ext_header_len;
625 struct sockaddr_in sin;
627 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
629 if (__ipv6_only_sock(sk))
632 sin.sin_family = AF_INET;
633 sin.sin_port = usin->sin6_port;
634 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
636 tp->af_specific = &ipv6_mapped;
637 sk->sk_backlog_rcv = tcp_v4_do_rcv;
639 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
642 tp->ext_header_len = exthdrlen;
643 tp->af_specific = &ipv6_specific;
644 sk->sk_backlog_rcv = tcp_v6_do_rcv;
647 ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
649 ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
656 if (!ipv6_addr_any(&np->rcv_saddr))
657 saddr = &np->rcv_saddr;
659 fl.proto = IPPROTO_TCP;
660 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
661 ipv6_addr_copy(&fl.fl6_src,
662 (saddr ? saddr : &np->saddr));
663 fl.oif = sk->sk_bound_dev_if;
664 fl.fl_ip_dport = usin->sin6_port;
665 fl.fl_ip_sport = inet->sport;
667 if (np->opt && np->opt->srcrt) {
668 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
669 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
672 err = ip6_dst_lookup(sk, &dst, &fl);
679 ipv6_addr_copy(&np->rcv_saddr, saddr);
682 /* set the source address */
683 ipv6_addr_copy(&np->saddr, saddr);
684 inet->rcv_saddr = LOOPBACK4_IPV6;
686 ip6_dst_store(sk, dst, NULL);
687 sk->sk_route_caps = dst->dev->features &
688 ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
690 tp->ext_header_len = 0;
692 tp->ext_header_len = np->opt->opt_flen + np->opt->opt_nflen;
693 tp->ext2_header_len = dst->header_len;
695 tp->mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
697 inet->dport = usin->sin6_port;
699 tcp_set_state(sk, TCP_SYN_SENT);
700 err = tcp_v6_hash_connect(sk);
705 tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32,
710 err = tcp_connect(sk);
717 tcp_set_state(sk, TCP_CLOSE);
721 sk->sk_route_caps = 0;
725 static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
726 int type, int code, int offset, __u32 info)
728 struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
729 struct tcphdr *th = (struct tcphdr *)(skb->data+offset);
730 struct ipv6_pinfo *np;
736 sk = tcp_v6_lookup(&hdr->daddr, th->dest, &hdr->saddr, th->source, skb->dev->ifindex);
739 ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
743 if (sk->sk_state == TCP_TIME_WAIT) {
744 tcp_tw_put((struct tcp_tw_bucket*)sk);
749 if (sock_owned_by_user(sk))
750 NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);
752 if (sk->sk_state == TCP_CLOSE)
756 seq = ntohl(th->seq);
757 if (sk->sk_state != TCP_LISTEN &&
758 !between(seq, tp->snd_una, tp->snd_nxt)) {
759 NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
765 if (type == ICMPV6_PKT_TOOBIG) {
766 struct dst_entry *dst = NULL;
768 if (sock_owned_by_user(sk))
770 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
773 /* icmp should have updated the destination cache entry */
774 dst = __sk_dst_check(sk, np->dst_cookie);
777 struct inet_opt *inet = inet_sk(sk);
780 /* BUGGG_FUTURE: Again, it is not clear how
781 to handle rthdr case. Ignore this complexity
784 memset(&fl, 0, sizeof(fl));
785 fl.proto = IPPROTO_TCP;
786 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
787 ipv6_addr_copy(&fl.fl6_src, &np->saddr);
788 fl.oif = sk->sk_bound_dev_if;
789 fl.fl_ip_dport = inet->dport;
790 fl.fl_ip_sport = inet->sport;
792 if ((err = ip6_dst_lookup(sk, &dst, &fl))) {
793 sk->sk_err_soft = -err;
799 if (tp->pmtu_cookie > dst_pmtu(dst)) {
800 tcp_sync_mss(sk, dst_pmtu(dst));
801 tcp_simple_retransmit(sk);
802 } /* else let the usual retransmit timer handle it */
807 icmpv6_err_convert(type, code, &err);
809 /* Might be for an open_request */
810 switch (sk->sk_state) {
811 struct open_request *req, **prev;
813 if (sock_owned_by_user(sk))
816 req = tcp_v6_search_req(tp, &prev, th->dest, &hdr->daddr,
817 &hdr->saddr, tcp_v6_iif(skb));
821 /* ICMPs are not backlogged, hence we cannot get
822 * an established socket here.
824 BUG_TRAP(req->sk == NULL);
826 if (seq != req->snt_isn) {
827 NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
831 tcp_synq_drop(sk, req, prev);
835 case TCP_SYN_RECV: /* Cannot happen.
836 It can, it SYNs are crossed. --ANK */
837 if (!sock_owned_by_user(sk)) {
838 TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS);
840 sk->sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */
844 sk->sk_err_soft = err;
848 if (!sock_owned_by_user(sk) && np->recverr) {
850 sk->sk_error_report(sk);
852 sk->sk_err_soft = err;
860 static int tcp_v6_send_synack(struct sock *sk, struct open_request *req,
861 struct dst_entry *dst)
863 struct ipv6_pinfo *np = inet6_sk(sk);
864 struct sk_buff * skb;
865 struct ipv6_txoptions *opt = NULL;
869 memset(&fl, 0, sizeof(fl));
870 fl.proto = IPPROTO_TCP;
871 ipv6_addr_copy(&fl.fl6_dst, &req->af.v6_req.rmt_addr);
872 ipv6_addr_copy(&fl.fl6_src, &req->af.v6_req.loc_addr);
873 fl.fl6_flowlabel = 0;
874 fl.oif = req->af.v6_req.iif;
875 fl.fl_ip_dport = req->rmt_port;
876 fl.fl_ip_sport = inet_sk(sk)->sport;
881 np->rxopt.bits.srcrt == 2 &&
882 req->af.v6_req.pktopts) {
883 struct sk_buff *pktopts = req->af.v6_req.pktopts;
884 struct inet6_skb_parm *rxopt = IP6CB(pktopts);
886 opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr*)(pktopts->nh.raw + rxopt->srcrt));
889 if (opt && opt->srcrt) {
890 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
891 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
894 err = ip6_dst_lookup(sk, &dst, &fl);
899 skb = tcp_make_synack(sk, dst, req);
901 struct tcphdr *th = skb->h.th;
903 th->check = tcp_v6_check(th, skb->len,
904 &req->af.v6_req.loc_addr, &req->af.v6_req.rmt_addr,
905 csum_partial((char *)th, skb->len, skb->csum));
907 ipv6_addr_copy(&fl.fl6_dst, &req->af.v6_req.rmt_addr);
908 err = ip6_xmit(sk, skb, &fl, opt, 0);
909 if (err == NET_XMIT_CN)
915 if (opt && opt != np->opt)
916 sock_kfree_s(sk, opt, opt->tot_len);
920 static void tcp_v6_or_free(struct open_request *req)
922 if (req->af.v6_req.pktopts)
923 kfree_skb(req->af.v6_req.pktopts);
926 static struct or_calltable or_ipv6 = {
928 .rtx_syn_ack = tcp_v6_send_synack,
929 .send_ack = tcp_v6_or_send_ack,
930 .destructor = tcp_v6_or_free,
931 .send_reset = tcp_v6_send_reset
934 static int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
936 struct ipv6_pinfo *np = inet6_sk(sk);
937 struct inet6_skb_parm *opt = IP6CB(skb);
940 if ((opt->hop && np->rxopt.bits.hopopts) ||
941 ((IPV6_FLOWINFO_MASK&*(u32*)skb->nh.raw) &&
942 np->rxopt.bits.rxflow) ||
943 (opt->srcrt && np->rxopt.bits.srcrt) ||
944 ((opt->dst1 || opt->dst0) && np->rxopt.bits.dstopts))
951 static void tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len,
954 struct ipv6_pinfo *np = inet6_sk(sk);
956 if (skb->ip_summed == CHECKSUM_HW) {
957 th->check = ~csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP, 0);
958 skb->csum = offsetof(struct tcphdr, check);
960 th->check = csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP,
961 csum_partial((char *)th, th->doff<<2,
967 static void tcp_v6_send_reset(struct sk_buff *skb)
969 struct tcphdr *th = skb->h.th, *t1;
970 struct sk_buff *buff;
976 if (!ipv6_unicast_destination(skb))
980 * We need to grab some memory, and put together an RST,
981 * and then put it into the queue to be sent.
984 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr), GFP_ATOMIC);
988 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr));
990 t1 = (struct tcphdr *) skb_push(buff,sizeof(struct tcphdr));
992 /* Swap the send and the receive. */
993 memset(t1, 0, sizeof(*t1));
994 t1->dest = th->source;
995 t1->source = th->dest;
996 t1->doff = sizeof(*t1)/4;
1000 t1->seq = th->ack_seq;
1003 t1->ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin
1004 + skb->len - (th->doff<<2));
1007 buff->csum = csum_partial((char *)t1, sizeof(*t1), 0);
1009 memset(&fl, 0, sizeof(fl));
1010 ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr);
1011 ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr);
1013 t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst,
1014 sizeof(*t1), IPPROTO_TCP,
1017 fl.proto = IPPROTO_TCP;
1018 fl.oif = tcp_v6_iif(skb);
1019 fl.fl_ip_dport = t1->dest;
1020 fl.fl_ip_sport = t1->source;
1022 /* sk = NULL, but it is safe for now. RST socket required. */
1023 if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {
1024 ip6_xmit(NULL, buff, &fl, NULL, 0);
1025 TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
1026 TCP_INC_STATS_BH(TCP_MIB_OUTRSTS);
1033 static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts)
1035 struct tcphdr *th = skb->h.th, *t1;
1036 struct sk_buff *buff;
1038 int tot_len = sizeof(struct tcphdr);
1040 buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr), GFP_ATOMIC);
1044 skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr));
1049 t1 = (struct tcphdr *) skb_push(buff,tot_len);
1051 /* Swap the send and the receive. */
1052 memset(t1, 0, sizeof(*t1));
1053 t1->dest = th->source;
1054 t1->source = th->dest;
1055 t1->doff = tot_len/4;
1056 t1->seq = htonl(seq);
1057 t1->ack_seq = htonl(ack);
1059 t1->window = htons(win);
1062 u32 *ptr = (u32*)(t1 + 1);
1063 *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
1064 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
1065 *ptr++ = htonl(tcp_time_stamp);
1069 buff->csum = csum_partial((char *)t1, tot_len, 0);
1071 memset(&fl, 0, sizeof(fl));
1072 ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr);
1073 ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr);
1075 t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst,
1076 tot_len, IPPROTO_TCP,
1079 fl.proto = IPPROTO_TCP;
1080 fl.oif = tcp_v6_iif(skb);
1081 fl.fl_ip_dport = t1->dest;
1082 fl.fl_ip_sport = t1->source;
1084 if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {
1085 ip6_xmit(NULL, buff, &fl, NULL, 0);
1086 TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
1093 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
1095 struct tcp_tw_bucket *tw = (struct tcp_tw_bucket *)sk;
1097 tcp_v6_send_ack(skb, tw->tw_snd_nxt, tw->tw_rcv_nxt,
1098 tw->tw_rcv_wnd >> tw->tw_rcv_wscale, tw->tw_ts_recent);
1103 static void tcp_v6_or_send_ack(struct sk_buff *skb, struct open_request *req)
1105 tcp_v6_send_ack(skb, req->snt_isn+1, req->rcv_isn+1, req->rcv_wnd, req->ts_recent);
1109 static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
1111 struct open_request *req, **prev;
1112 struct tcphdr *th = skb->h.th;
1113 struct tcp_opt *tp = tcp_sk(sk);
1116 /* Find possible connection requests. */
1117 req = tcp_v6_search_req(tp, &prev, th->source, &skb->nh.ipv6h->saddr,
1118 &skb->nh.ipv6h->daddr, tcp_v6_iif(skb));
1120 return tcp_check_req(sk, skb, req, prev);
1122 nsk = __tcp_v6_lookup_established(&skb->nh.ipv6h->saddr,
1124 &skb->nh.ipv6h->daddr,
1129 if (nsk->sk_state != TCP_TIME_WAIT) {
1133 tcp_tw_put((struct tcp_tw_bucket*)nsk);
1137 #if 0 /*def CONFIG_SYN_COOKIES*/
1138 if (!th->rst && !th->syn && th->ack)
1139 sk = cookie_v6_check(sk, skb, &(IPCB(skb)->opt));
1144 static void tcp_v6_synq_add(struct sock *sk, struct open_request *req)
1146 struct tcp_opt *tp = tcp_sk(sk);
1147 struct tcp_listen_opt *lopt = tp->listen_opt;
1148 u32 h = tcp_v6_synq_hash(&req->af.v6_req.rmt_addr, req->rmt_port, lopt->hash_rnd);
1151 req->expires = jiffies + TCP_TIMEOUT_INIT;
1153 req->dl_next = lopt->syn_table[h];
1155 write_lock(&tp->syn_wait_lock);
1156 lopt->syn_table[h] = req;
1157 write_unlock(&tp->syn_wait_lock);
1163 /* FIXME: this is substantially similar to the ipv4 code.
1164 * Can some kind of merge be done? -- erics
1166 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
1168 struct ipv6_pinfo *np = inet6_sk(sk);
1169 struct tcp_opt tmptp, *tp = tcp_sk(sk);
1170 struct open_request *req = NULL;
1171 __u32 isn = TCP_SKB_CB(skb)->when;
1173 if (skb->protocol == htons(ETH_P_IP))
1174 return tcp_v4_conn_request(sk, skb);
1176 if (!ipv6_unicast_destination(skb))
1180 * There are no SYN attacks on IPv6, yet...
1182 if (tcp_synq_is_full(sk) && !isn) {
1183 if (net_ratelimit())
1184 printk(KERN_INFO "TCPv6: dropping request, synflood is possible\n");
1188 if (sk_acceptq_is_full(sk) && tcp_synq_young(sk) > 1)
1191 req = tcp_openreq_alloc();
1195 tcp_clear_options(&tmptp);
1196 tmptp.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
1197 tmptp.user_mss = tp->user_mss;
1199 tcp_parse_options(skb, &tmptp, 0);
1201 tmptp.tstamp_ok = tmptp.saw_tstamp;
1202 tcp_openreq_init(req, &tmptp, skb);
1204 req->class = &or_ipv6;
1205 ipv6_addr_copy(&req->af.v6_req.rmt_addr, &skb->nh.ipv6h->saddr);
1206 ipv6_addr_copy(&req->af.v6_req.loc_addr, &skb->nh.ipv6h->daddr);
1207 TCP_ECN_create_request(req, skb->h.th);
1208 req->af.v6_req.pktopts = NULL;
1209 if (ipv6_opt_accepted(sk, skb) ||
1210 np->rxopt.bits.rxinfo ||
1211 np->rxopt.bits.rxhlim) {
1212 atomic_inc(&skb->users);
1213 req->af.v6_req.pktopts = skb;
1215 req->af.v6_req.iif = sk->sk_bound_dev_if;
1217 /* So that link locals have meaning */
1218 if (!sk->sk_bound_dev_if &&
1219 ipv6_addr_type(&req->af.v6_req.rmt_addr) & IPV6_ADDR_LINKLOCAL)
1220 req->af.v6_req.iif = tcp_v6_iif(skb);
1223 isn = tcp_v6_init_sequence(sk,skb);
1227 if (tcp_v6_send_synack(sk, req, NULL))
1230 tcp_v6_synq_add(sk, req);
1236 tcp_openreq_free(req);
1238 TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS);
1239 return 0; /* don't send reset */
1242 static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
1243 struct open_request *req,
1244 struct dst_entry *dst)
1246 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
1247 struct tcp6_sock *newtcp6sk;
1248 struct inet_opt *newinet;
1249 struct tcp_opt *newtp;
1251 struct ipv6_txoptions *opt;
1253 if (skb->protocol == htons(ETH_P_IP)) {
1258 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst);
1263 newtcp6sk = (struct tcp6_sock *)newsk;
1264 newtcp6sk->pinet6 = &newtcp6sk->inet6;
1266 newinet = inet_sk(newsk);
1267 newnp = inet6_sk(newsk);
1268 newtp = tcp_sk(newsk);
1270 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1272 ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF),
1275 ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF),
1278 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
1280 newtp->af_specific = &ipv6_mapped;
1281 newsk->sk_backlog_rcv = tcp_v4_do_rcv;
1282 newnp->pktoptions = NULL;
1284 newnp->mcast_oif = tcp_v6_iif(skb);
1285 newnp->mcast_hops = skb->nh.ipv6h->hop_limit;
1287 /* Charge newly allocated IPv6 socket. Though it is mapped,
1290 #ifdef INET_REFCNT_DEBUG
1291 atomic_inc(&inet6_sock_nr);
1294 /* It is tricky place. Until this moment IPv4 tcp
1295 worked with IPv6 af_tcp.af_specific.
1298 tcp_sync_mss(newsk, newtp->pmtu_cookie);
1305 if (sk_acceptq_is_full(sk))
1308 if (np->rxopt.bits.srcrt == 2 &&
1309 opt == NULL && req->af.v6_req.pktopts) {
1310 struct inet6_skb_parm *rxopt = IP6CB(req->af.v6_req.pktopts);
1312 opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr*)(req->af.v6_req.pktopts->nh.raw+rxopt->srcrt));
1318 memset(&fl, 0, sizeof(fl));
1319 fl.proto = IPPROTO_TCP;
1320 ipv6_addr_copy(&fl.fl6_dst, &req->af.v6_req.rmt_addr);
1321 if (opt && opt->srcrt) {
1322 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
1323 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
1325 ipv6_addr_copy(&fl.fl6_src, &req->af.v6_req.loc_addr);
1326 fl.oif = sk->sk_bound_dev_if;
1327 fl.fl_ip_dport = req->rmt_port;
1328 fl.fl_ip_sport = inet_sk(sk)->sport;
1330 if (ip6_dst_lookup(sk, &dst, &fl))
1334 newsk = tcp_create_openreq_child(sk, req, skb);
1338 /* Charge newly allocated IPv6 socket */
1339 #ifdef INET_REFCNT_DEBUG
1340 atomic_inc(&inet6_sock_nr);
1343 ip6_dst_store(newsk, dst, NULL);
1344 newsk->sk_route_caps = dst->dev->features &
1345 ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
1347 newtcp6sk = (struct tcp6_sock *)newsk;
1348 newtcp6sk->pinet6 = &newtcp6sk->inet6;
1350 newtp = tcp_sk(newsk);
1351 newinet = inet_sk(newsk);
1352 newnp = inet6_sk(newsk);
1354 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1356 ipv6_addr_copy(&newnp->daddr, &req->af.v6_req.rmt_addr);
1357 ipv6_addr_copy(&newnp->saddr, &req->af.v6_req.loc_addr);
1358 ipv6_addr_copy(&newnp->rcv_saddr, &req->af.v6_req.loc_addr);
1359 newsk->sk_bound_dev_if = req->af.v6_req.iif;
1361 /* Now IPv6 options...
1363 First: no IPv4 options.
1365 newinet->opt = NULL;
1368 newnp->rxopt.all = np->rxopt.all;
1370 /* Clone pktoptions received with SYN */
1371 newnp->pktoptions = NULL;
1372 if (req->af.v6_req.pktopts) {
1373 newnp->pktoptions = skb_clone(req->af.v6_req.pktopts,
1375 kfree_skb(req->af.v6_req.pktopts);
1376 req->af.v6_req.pktopts = NULL;
1377 if (newnp->pktoptions)
1378 skb_set_owner_r(newnp->pktoptions, newsk);
1381 newnp->mcast_oif = tcp_v6_iif(skb);
1382 newnp->mcast_hops = skb->nh.ipv6h->hop_limit;
1384 /* Clone native IPv6 options from listening socket (if any)
1386 Yes, keeping reference count would be much more clever,
1387 but we make one more one thing there: reattach optmem
1391 newnp->opt = ipv6_dup_options(newsk, opt);
1393 sock_kfree_s(sk, opt, opt->tot_len);
1396 newtp->ext_header_len = 0;
1398 newtp->ext_header_len = newnp->opt->opt_nflen +
1399 newnp->opt->opt_flen;
1400 newtp->ext2_header_len = dst->header_len;
1402 tcp_sync_mss(newsk, dst_pmtu(dst));
1403 newtp->advmss = dst_metric(dst, RTAX_ADVMSS);
1404 tcp_initialize_rcv_mss(newsk);
1406 newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;
1408 __tcp_v6_hash(newsk);
1409 tcp_inherit_port(sk, newsk);
1414 NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
1416 NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
1417 if (opt && opt != np->opt)
1418 sock_kfree_s(sk, opt, opt->tot_len);
1423 static int tcp_v6_checksum_init(struct sk_buff *skb)
1425 if (skb->ip_summed == CHECKSUM_HW) {
1426 skb->ip_summed = CHECKSUM_UNNECESSARY;
1427 if (!tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
1428 &skb->nh.ipv6h->daddr,skb->csum))
1430 LIMIT_NETDEBUG(printk(KERN_DEBUG "hw tcp v6 csum failed\n"));
1432 if (skb->len <= 76) {
1433 if (tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
1434 &skb->nh.ipv6h->daddr,skb_checksum(skb, 0, skb->len, 0)))
1436 skb->ip_summed = CHECKSUM_UNNECESSARY;
1438 skb->csum = ~tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
1439 &skb->nh.ipv6h->daddr,0);
1444 /* The socket must have it's spinlock held when we get
1447 * We have a potential double-lock case here, so even when
1448 * doing backlog processing we use the BH locking scheme.
1449 * This is because we cannot sleep with the original spinlock
1452 static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
1454 struct ipv6_pinfo *np = inet6_sk(sk);
1456 struct sk_buff *opt_skb = NULL;
1458 /* Imagine: socket is IPv6. IPv4 packet arrives,
1459 goes to IPv4 receive handler and backlogged.
1460 From backlog it always goes here. Kerboom...
1461 Fortunately, tcp_rcv_established and rcv_established
1462 handle them correctly, but it is not case with
1463 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK
1466 if (skb->protocol == htons(ETH_P_IP))
1467 return tcp_v4_do_rcv(sk, skb);
1469 if (sk_filter(sk, skb, 0))
1473 * socket locking is here for SMP purposes as backlog rcv
1474 * is currently called with bh processing disabled.
1477 /* Do Stevens' IPV6_PKTOPTIONS.
1479 Yes, guys, it is the only place in our code, where we
1480 may make it not affecting IPv4.
1481 The rest of code is protocol independent,
1482 and I do not like idea to uglify IPv4.
1484 Actually, all the idea behind IPV6_PKTOPTIONS
1485 looks not very well thought. For now we latch
1486 options, received in the last packet, enqueued
1487 by tcp. Feel free to propose better solution.
1491 opt_skb = skb_clone(skb, GFP_ATOMIC);
1493 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
1494 TCP_CHECK_TIMER(sk);
1495 if (tcp_rcv_established(sk, skb, skb->h.th, skb->len))
1497 TCP_CHECK_TIMER(sk);
1499 goto ipv6_pktoptions;
1503 if (skb->len < (skb->h.th->doff<<2) || tcp_checksum_complete(skb))
1506 if (sk->sk_state == TCP_LISTEN) {
1507 struct sock *nsk = tcp_v6_hnd_req(sk, skb);
1512 * Queue it on the new socket if the new socket is active,
1513 * otherwise we just shortcircuit this and continue with
1517 if (tcp_child_process(sk, nsk, skb))
1520 __kfree_skb(opt_skb);
1525 TCP_CHECK_TIMER(sk);
1526 if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len))
1528 TCP_CHECK_TIMER(sk);
1530 goto ipv6_pktoptions;
1534 tcp_v6_send_reset(skb);
1537 __kfree_skb(opt_skb);
1541 TCP_INC_STATS_BH(TCP_MIB_INERRS);
1546 /* Do you ask, what is it?
1548 1. skb was enqueued by tcp.
1549 2. skb is added to tail of read queue, rather than out of order.
1550 3. socket is not in passive state.
1551 4. Finally, it really contains options, which user wants to receive.
1554 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt &&
1555 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) {
1556 if (np->rxopt.bits.rxinfo)
1557 np->mcast_oif = tcp_v6_iif(opt_skb);
1558 if (np->rxopt.bits.rxhlim)
1559 np->mcast_hops = opt_skb->nh.ipv6h->hop_limit;
1560 if (ipv6_opt_accepted(sk, opt_skb)) {
1561 skb_set_owner_r(opt_skb, sk);
1562 opt_skb = xchg(&np->pktoptions, opt_skb);
1564 __kfree_skb(opt_skb);
1565 opt_skb = xchg(&np->pktoptions, NULL);
1574 static int tcp_v6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
1576 struct sk_buff *skb = *pskb;
1581 if (skb->pkt_type != PACKET_HOST)
1585 * Count it even if it's bad.
1587 TCP_INC_STATS_BH(TCP_MIB_INSEGS);
1589 if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
1594 if (th->doff < sizeof(struct tcphdr)/4)
1596 if (!pskb_may_pull(skb, th->doff*4))
1599 if ((skb->ip_summed != CHECKSUM_UNNECESSARY &&
1600 tcp_v6_checksum_init(skb) < 0))
1604 TCP_SKB_CB(skb)->seq = ntohl(th->seq);
1605 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
1606 skb->len - th->doff*4);
1607 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
1608 TCP_SKB_CB(skb)->when = 0;
1609 TCP_SKB_CB(skb)->flags = ip6_get_dsfield(skb->nh.ipv6h);
1610 TCP_SKB_CB(skb)->sacked = 0;
1612 sk = __tcp_v6_lookup(&skb->nh.ipv6h->saddr, th->source,
1613 &skb->nh.ipv6h->daddr, ntohs(th->dest), tcp_v6_iif(skb));
1619 if (sk->sk_state == TCP_TIME_WAIT)
1622 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
1623 goto discard_and_relse;
1625 if (sk_filter(sk, skb, 0))
1626 goto discard_and_relse;
1632 if (!sock_owned_by_user(sk)) {
1633 if (!tcp_prequeue(sk, skb))
1634 ret = tcp_v6_do_rcv(sk, skb);
1636 sk_add_backlog(sk, skb);
1640 return ret ? -1 : 0;
1643 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
1646 if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
1648 TCP_INC_STATS_BH(TCP_MIB_INERRS);
1650 tcp_v6_send_reset(skb);
1667 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
1668 tcp_tw_put((struct tcp_tw_bucket *) sk);
1672 if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
1673 TCP_INC_STATS_BH(TCP_MIB_INERRS);
1674 tcp_tw_put((struct tcp_tw_bucket *) sk);
1678 switch(tcp_timewait_state_process((struct tcp_tw_bucket *)sk,
1679 skb, th, skb->len)) {
1684 sk2 = tcp_v6_lookup_listener(&skb->nh.ipv6h->daddr, ntohs(th->dest), tcp_v6_iif(skb));
1686 tcp_tw_deschedule((struct tcp_tw_bucket *)sk);
1687 tcp_tw_put((struct tcp_tw_bucket *)sk);
1691 /* Fall through to ACK */
1694 tcp_v6_timewait_ack(sk, skb);
1698 case TCP_TW_SUCCESS:;
1703 static int tcp_v6_rebuild_header(struct sock *sk)
1706 struct dst_entry *dst;
1707 struct ipv6_pinfo *np = inet6_sk(sk);
1709 dst = __sk_dst_check(sk, np->dst_cookie);
1712 struct inet_opt *inet = inet_sk(sk);
1715 memset(&fl, 0, sizeof(fl));
1716 fl.proto = IPPROTO_TCP;
1717 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
1718 ipv6_addr_copy(&fl.fl6_src, &np->saddr);
1719 fl.fl6_flowlabel = np->flow_label;
1720 fl.oif = sk->sk_bound_dev_if;
1721 fl.fl_ip_dport = inet->dport;
1722 fl.fl_ip_sport = inet->sport;
1724 if (np->opt && np->opt->srcrt) {
1725 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
1726 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
1729 err = ip6_dst_lookup(sk, &dst, &fl);
1732 sk->sk_route_caps = 0;
1736 ip6_dst_store(sk, dst, NULL);
1737 sk->sk_route_caps = dst->dev->features &
1738 ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
1739 tcp_sk(sk)->ext2_header_len = dst->header_len;
1745 static int tcp_v6_xmit(struct sk_buff *skb, int ipfragok)
1747 struct sock *sk = skb->sk;
1748 struct inet_opt *inet = inet_sk(sk);
1749 struct ipv6_pinfo *np = inet6_sk(sk);
1751 struct dst_entry *dst;
1753 memset(&fl, 0, sizeof(fl));
1754 fl.proto = IPPROTO_TCP;
1755 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
1756 ipv6_addr_copy(&fl.fl6_src, &np->saddr);
1757 fl.fl6_flowlabel = np->flow_label;
1758 IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
1759 fl.oif = sk->sk_bound_dev_if;
1760 fl.fl_ip_sport = inet->sport;
1761 fl.fl_ip_dport = inet->dport;
1763 if (np->opt && np->opt->srcrt) {
1764 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
1765 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
1768 dst = __sk_dst_check(sk, np->dst_cookie);
1771 int err = ip6_dst_lookup(sk, &dst, &fl);
1774 sk->sk_err_soft = -err;
1778 ip6_dst_store(sk, dst, NULL);
1779 sk->sk_route_caps = dst->dev->features &
1780 ~(NETIF_F_IP_CSUM | NETIF_F_TSO);
1781 tcp_sk(sk)->ext2_header_len = dst->header_len;
1784 skb->dst = dst_clone(dst);
1786 /* Restore final destination back after routing done */
1787 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
1789 return ip6_xmit(sk, skb, &fl, np->opt, 0);
1792 static void v6_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr)
1794 struct ipv6_pinfo *np = inet6_sk(sk);
1795 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr;
1797 sin6->sin6_family = AF_INET6;
1798 ipv6_addr_copy(&sin6->sin6_addr, &np->daddr);
1799 sin6->sin6_port = inet_sk(sk)->dport;
1800 /* We do not store received flowlabel for TCP */
1801 sin6->sin6_flowinfo = 0;
1802 sin6->sin6_scope_id = 0;
1803 if (sk->sk_bound_dev_if &&
1804 ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
1805 sin6->sin6_scope_id = sk->sk_bound_dev_if;
1808 static int tcp_v6_remember_stamp(struct sock *sk)
1810 /* Alas, not yet... */
1814 static struct tcp_func ipv6_specific = {
1815 .queue_xmit = tcp_v6_xmit,
1816 .send_check = tcp_v6_send_check,
1817 .rebuild_header = tcp_v6_rebuild_header,
1818 .conn_request = tcp_v6_conn_request,
1819 .syn_recv_sock = tcp_v6_syn_recv_sock,
1820 .remember_stamp = tcp_v6_remember_stamp,
1821 .net_header_len = sizeof(struct ipv6hdr),
1823 .setsockopt = ipv6_setsockopt,
1824 .getsockopt = ipv6_getsockopt,
1825 .addr2sockaddr = v6_addr2sockaddr,
1826 .sockaddr_len = sizeof(struct sockaddr_in6)
1830 * TCP over IPv4 via INET6 API
1833 static struct tcp_func ipv6_mapped = {
1834 .queue_xmit = ip_queue_xmit,
1835 .send_check = tcp_v4_send_check,
1836 .rebuild_header = tcp_v4_rebuild_header,
1837 .conn_request = tcp_v6_conn_request,
1838 .syn_recv_sock = tcp_v6_syn_recv_sock,
1839 .remember_stamp = tcp_v4_remember_stamp,
1840 .net_header_len = sizeof(struct iphdr),
1842 .setsockopt = ipv6_setsockopt,
1843 .getsockopt = ipv6_getsockopt,
1844 .addr2sockaddr = v6_addr2sockaddr,
1845 .sockaddr_len = sizeof(struct sockaddr_in6)
1850 /* NOTE: A lot of things set to zero explicitly by call to
1851 * sk_alloc() so need not be done here.
1853 static int tcp_v6_init_sock(struct sock *sk)
1855 struct tcp_opt *tp = tcp_sk(sk);
1857 skb_queue_head_init(&tp->out_of_order_queue);
1858 tcp_init_xmit_timers(sk);
1859 tcp_prequeue_init(tp);
1861 tp->rto = TCP_TIMEOUT_INIT;
1862 tp->mdev = TCP_TIMEOUT_INIT;
1864 /* So many TCP implementations out there (incorrectly) count the
1865 * initial SYN frame in their delayed-ACK and congestion control
1866 * algorithms that we must have the following bandaid to talk
1867 * efficiently to them. -DaveM
1871 /* See draft-stevens-tcpca-spec-01 for discussion of the
1872 * initialization of these values.
1874 tp->snd_ssthresh = 0x7fffffff;
1875 tp->snd_cwnd_clamp = ~0;
1876 tp->mss_cache = 536;
1878 tp->reordering = sysctl_tcp_reordering;
1880 sk->sk_state = TCP_CLOSE;
1882 tp->af_specific = &ipv6_specific;
1884 sk->sk_write_space = sk_stream_write_space;
1885 sk->sk_use_write_queue = 1;
1887 sk->sk_sndbuf = sysctl_tcp_wmem[1];
1888 sk->sk_rcvbuf = sysctl_tcp_rmem[1];
1890 atomic_inc(&tcp_sockets_allocated);
1895 static int tcp_v6_destroy_sock(struct sock *sk)
1897 extern int tcp_v4_destroy_sock(struct sock *sk);
1899 tcp_v4_destroy_sock(sk);
1900 return inet6_destroy_sock(sk);
1903 /* Proc filesystem TCPv6 sock list dumping. */
1904 static void get_openreq6(struct seq_file *seq,
1905 struct sock *sk, struct open_request *req, int i, int uid)
1907 struct in6_addr *dest, *src;
1908 int ttd = req->expires - jiffies;
1913 src = &req->af.v6_req.loc_addr;
1914 dest = &req->af.v6_req.rmt_addr;
1916 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1917 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n",
1919 src->s6_addr32[0], src->s6_addr32[1],
1920 src->s6_addr32[2], src->s6_addr32[3],
1921 ntohs(inet_sk(sk)->sport),
1922 dest->s6_addr32[0], dest->s6_addr32[1],
1923 dest->s6_addr32[2], dest->s6_addr32[3],
1924 ntohs(req->rmt_port),
1926 0,0, /* could print option size, but that is af dependent. */
1927 1, /* timers active (only the expire timer) */
1928 jiffies_to_clock_t(ttd),
1931 0, /* non standard timer */
1932 0, /* open_requests have no inode */
1936 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
1938 struct in6_addr *dest, *src;
1941 unsigned long timer_expires;
1942 struct inet_opt *inet = inet_sk(sp);
1943 struct tcp_opt *tp = tcp_sk(sp);
1944 struct ipv6_pinfo *np = inet6_sk(sp);
1947 src = &np->rcv_saddr;
1948 destp = ntohs(inet->dport);
1949 srcp = ntohs(inet->sport);
1950 if (tp->pending == TCP_TIME_RETRANS) {
1952 timer_expires = tp->timeout;
1953 } else if (tp->pending == TCP_TIME_PROBE0) {
1955 timer_expires = tp->timeout;
1956 } else if (timer_pending(&sp->sk_timer)) {
1958 timer_expires = sp->sk_timer.expires;
1961 timer_expires = jiffies;
1965 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1966 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %u %u %u %u %d\n",
1968 src->s6_addr32[0], src->s6_addr32[1],
1969 src->s6_addr32[2], src->s6_addr32[3], srcp,
1970 dest->s6_addr32[0], dest->s6_addr32[1],
1971 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1973 tp->write_seq-tp->snd_una, tp->rcv_nxt-tp->copied_seq,
1975 jiffies_to_clock_t(timer_expires - jiffies),
1980 atomic_read(&sp->sk_refcnt), sp,
1981 tp->rto, tp->ack.ato, (tp->ack.quick<<1)|tp->ack.pingpong,
1982 tp->snd_cwnd, tp->snd_ssthresh>=0xFFFF?-1:tp->snd_ssthresh
1986 static void get_timewait6_sock(struct seq_file *seq,
1987 struct tcp_tw_bucket *tw, int i)
1989 struct in6_addr *dest, *src;
1991 int ttd = tw->tw_ttd - jiffies;
1996 dest = &tw->tw_v6_daddr;
1997 src = &tw->tw_v6_rcv_saddr;
1998 destp = ntohs(tw->tw_dport);
1999 srcp = ntohs(tw->tw_sport);
2002 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
2003 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n",
2005 src->s6_addr32[0], src->s6_addr32[1],
2006 src->s6_addr32[2], src->s6_addr32[3], srcp,
2007 dest->s6_addr32[0], dest->s6_addr32[1],
2008 dest->s6_addr32[2], dest->s6_addr32[3], destp,
2009 tw->tw_substate, 0, 0,
2010 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0,
2011 atomic_read(&tw->tw_refcnt), tw);
2014 #ifdef CONFIG_PROC_FS
2015 static int tcp6_seq_show(struct seq_file *seq, void *v)
2017 struct tcp_iter_state *st;
2019 if (v == SEQ_START_TOKEN) {
2024 "st tx_queue rx_queue tr tm->when retrnsmt"
2025 " uid timeout inode\n");
2030 switch (st->state) {
2031 case TCP_SEQ_STATE_LISTENING:
2032 case TCP_SEQ_STATE_ESTABLISHED:
2033 get_tcp6_sock(seq, v, st->num);
2035 case TCP_SEQ_STATE_OPENREQ:
2036 get_openreq6(seq, st->syn_wait_sk, v, st->num, st->uid);
2038 case TCP_SEQ_STATE_TIME_WAIT:
2039 get_timewait6_sock(seq, v, st->num);
2046 static struct file_operations tcp6_seq_fops;
2047 static struct tcp_seq_afinfo tcp6_seq_afinfo = {
2048 .owner = THIS_MODULE,
2051 .seq_show = tcp6_seq_show,
2052 .seq_fops = &tcp6_seq_fops,
2055 int __init tcp6_proc_init(void)
2057 return tcp_proc_register(&tcp6_seq_afinfo);
2060 void tcp6_proc_exit(void)
2062 tcp_proc_unregister(&tcp6_seq_afinfo);
2066 struct proto tcpv6_prot = {
2069 .connect = tcp_v6_connect,
2070 .disconnect = tcp_disconnect,
2071 .accept = tcp_accept,
2073 .init = tcp_v6_init_sock,
2074 .destroy = tcp_v6_destroy_sock,
2075 .shutdown = tcp_shutdown,
2076 .setsockopt = tcp_setsockopt,
2077 .getsockopt = tcp_getsockopt,
2078 .sendmsg = tcp_sendmsg,
2079 .recvmsg = tcp_recvmsg,
2080 .backlog_rcv = tcp_v6_do_rcv,
2081 .hash = tcp_v6_hash,
2082 .unhash = tcp_unhash,
2083 .get_port = tcp_v6_get_port,
2084 .enter_memory_pressure = tcp_enter_memory_pressure,
2085 .sockets_allocated = &tcp_sockets_allocated,
2086 .memory_allocated = &tcp_memory_allocated,
2087 .memory_pressure = &tcp_memory_pressure,
2088 .sysctl_mem = sysctl_tcp_mem,
2089 .sysctl_wmem = sysctl_tcp_wmem,
2090 .sysctl_rmem = sysctl_tcp_rmem,
2091 .max_header = MAX_TCP_HEADER,
2094 static struct inet6_protocol tcpv6_protocol = {
2095 .handler = tcp_v6_rcv,
2096 .err_handler = tcp_v6_err,
2097 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
2100 extern struct proto_ops inet6_stream_ops;
2102 static struct inet_protosw tcpv6_protosw = {
2103 .type = SOCK_STREAM,
2104 .protocol = IPPROTO_TCP,
2105 .prot = &tcpv6_prot,
2106 .ops = &inet6_stream_ops,
2109 .flags = INET_PROTOSW_PERMANENT,
2112 void __init tcpv6_init(void)
2114 /* register inet6 protocol */
2115 if (inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP) < 0)
2116 printk(KERN_ERR "tcpv6_init: Could not register protocol\n");
2117 inet6_register_protosw(&tcpv6_protosw);