1 // SPDX-License-Identifier: GPL-2.0-or-later
4 * Linux INET6 implementation
7 * Pedro Roque <roque@di.fc.ul.pt>
10 * linux/net/ipv4/tcp.c
11 * linux/net/ipv4/tcp_input.c
12 * linux/net/ipv4/tcp_output.c
15 * Hideaki YOSHIFUJI : sin6_scope_id support
16 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
17 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
18 * a single port at the same time.
19 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/tcp6 to seq_file.
22 #include <linux/bottom_half.h>
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/socket.h>
27 #include <linux/sockios.h>
28 #include <linux/net.h>
29 #include <linux/jiffies.h>
31 #include <linux/in6.h>
32 #include <linux/netdevice.h>
33 #include <linux/init.h>
34 #include <linux/jhash.h>
35 #include <linux/ipsec.h>
36 #include <linux/times.h>
37 #include <linux/slab.h>
38 #include <linux/uaccess.h>
39 #include <linux/ipv6.h>
40 #include <linux/icmpv6.h>
41 #include <linux/random.h>
42 #include <linux/indirect_call_wrapper.h>
45 #include <net/ndisc.h>
46 #include <net/inet6_hashtables.h>
47 #include <net/inet6_connection_sock.h>
49 #include <net/transp_v6.h>
50 #include <net/addrconf.h>
51 #include <net/ip6_route.h>
52 #include <net/ip6_checksum.h>
53 #include <net/inet_ecn.h>
54 #include <net/protocol.h>
57 #include <net/dsfield.h>
58 #include <net/timewait_sock.h>
59 #include <net/inet_common.h>
60 #include <net/secure_seq.h>
61 #include <net/busy_poll.h>
63 #include <linux/proc_fs.h>
64 #include <linux/seq_file.h>
66 #include <crypto/hash.h>
67 #include <linux/scatterlist.h>
69 #include <trace/events/tcp.h>
71 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb);
72 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
73 struct request_sock *req);
75 INDIRECT_CALLABLE_SCOPE int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
77 static const struct inet_connection_sock_af_ops ipv6_mapped;
78 const struct inet_connection_sock_af_ops ipv6_specific;
79 #ifdef CONFIG_TCP_MD5SIG
80 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific;
81 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific;
83 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(const struct sock *sk,
84 const struct in6_addr *addr,
91 /* Helper returning the inet6 address from a given tcp socket.
92 * It can be used in TCP stack instead of inet6_sk(sk).
93 * This avoids a dereference and allow compiler optimizations.
94 * It is a specialized version of inet6_sk_generic().
96 static struct ipv6_pinfo *tcp_inet6_sk(const struct sock *sk)
98 unsigned int offset = sizeof(struct tcp6_sock) - sizeof(struct ipv6_pinfo);
100 return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
103 static void inet6_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb)
105 struct dst_entry *dst = skb_dst(skb);
107 if (dst && dst_hold_safe(dst)) {
108 const struct rt6_info *rt = (const struct rt6_info *)dst;
110 rcu_assign_pointer(sk->sk_rx_dst, dst);
111 sk->sk_rx_dst_ifindex = skb->skb_iif;
112 sk->sk_rx_dst_cookie = rt6_get_cookie(rt);
116 static u32 tcp_v6_init_seq(const struct sk_buff *skb)
118 return secure_tcpv6_seq(ipv6_hdr(skb)->daddr.s6_addr32,
119 ipv6_hdr(skb)->saddr.s6_addr32,
121 tcp_hdr(skb)->source);
124 static u32 tcp_v6_init_ts_off(const struct net *net, const struct sk_buff *skb)
126 return secure_tcpv6_ts_off(net, ipv6_hdr(skb)->daddr.s6_addr32,
127 ipv6_hdr(skb)->saddr.s6_addr32);
130 static int tcp_v6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
133 /* This check is replicated from tcp_v6_connect() and intended to
134 * prevent BPF program called below from accessing bytes that are out
135 * of the bound specified by user in addr_len.
137 if (addr_len < SIN6_LEN_RFC2133)
140 sock_owned_by_me(sk);
142 return BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr);
145 static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
148 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
149 struct inet_connection_sock *icsk = inet_csk(sk);
150 struct in6_addr *saddr = NULL, *final_p, final;
151 struct inet_timewait_death_row *tcp_death_row;
152 struct ipv6_pinfo *np = tcp_inet6_sk(sk);
153 struct inet_sock *inet = inet_sk(sk);
154 struct tcp_sock *tp = tcp_sk(sk);
155 struct net *net = sock_net(sk);
156 struct ipv6_txoptions *opt;
157 struct dst_entry *dst;
162 if (addr_len < SIN6_LEN_RFC2133)
165 if (usin->sin6_family != AF_INET6)
166 return -EAFNOSUPPORT;
168 memset(&fl6, 0, sizeof(fl6));
171 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
172 IP6_ECN_flow_init(fl6.flowlabel);
173 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
174 struct ip6_flowlabel *flowlabel;
175 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
176 if (IS_ERR(flowlabel))
178 fl6_sock_release(flowlabel);
183 * connect() to INADDR_ANY means loopback (BSD'ism).
186 if (ipv6_addr_any(&usin->sin6_addr)) {
187 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
188 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
191 usin->sin6_addr = in6addr_loopback;
194 addr_type = ipv6_addr_type(&usin->sin6_addr);
196 if (addr_type & IPV6_ADDR_MULTICAST)
199 if (addr_type&IPV6_ADDR_LINKLOCAL) {
200 if (addr_len >= sizeof(struct sockaddr_in6) &&
201 usin->sin6_scope_id) {
202 /* If interface is set while binding, indices
205 if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id))
208 sk->sk_bound_dev_if = usin->sin6_scope_id;
211 /* Connect to link-local address requires an interface */
212 if (!sk->sk_bound_dev_if)
216 if (tp->rx_opt.ts_recent_stamp &&
217 !ipv6_addr_equal(&sk->sk_v6_daddr, &usin->sin6_addr)) {
218 tp->rx_opt.ts_recent = 0;
219 tp->rx_opt.ts_recent_stamp = 0;
220 WRITE_ONCE(tp->write_seq, 0);
223 sk->sk_v6_daddr = usin->sin6_addr;
224 np->flow_label = fl6.flowlabel;
230 if (addr_type & IPV6_ADDR_MAPPED) {
231 u32 exthdrlen = icsk->icsk_ext_hdr_len;
232 struct sockaddr_in sin;
234 if (ipv6_only_sock(sk))
237 sin.sin_family = AF_INET;
238 sin.sin_port = usin->sin6_port;
239 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
241 /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */
242 WRITE_ONCE(icsk->icsk_af_ops, &ipv6_mapped);
244 mptcpv6_handle_mapped(sk, true);
245 sk->sk_backlog_rcv = tcp_v4_do_rcv;
246 #ifdef CONFIG_TCP_MD5SIG
247 tp->af_specific = &tcp_sock_ipv6_mapped_specific;
250 err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
253 icsk->icsk_ext_hdr_len = exthdrlen;
254 /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */
255 WRITE_ONCE(icsk->icsk_af_ops, &ipv6_specific);
257 mptcpv6_handle_mapped(sk, false);
258 sk->sk_backlog_rcv = tcp_v6_do_rcv;
259 #ifdef CONFIG_TCP_MD5SIG
260 tp->af_specific = &tcp_sock_ipv6_specific;
264 np->saddr = sk->sk_v6_rcv_saddr;
269 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr))
270 saddr = &sk->sk_v6_rcv_saddr;
272 fl6.flowi6_proto = IPPROTO_TCP;
273 fl6.daddr = sk->sk_v6_daddr;
274 fl6.saddr = saddr ? *saddr : np->saddr;
275 fl6.flowlabel = ip6_make_flowinfo(np->tclass, np->flow_label);
276 fl6.flowi6_oif = sk->sk_bound_dev_if;
277 fl6.flowi6_mark = sk->sk_mark;
278 fl6.fl6_dport = usin->sin6_port;
279 fl6.fl6_sport = inet->inet_sport;
280 fl6.flowi6_uid = sk->sk_uid;
282 opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
283 final_p = fl6_update_dst(&fl6, opt, &final);
285 security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
287 dst = ip6_dst_lookup_flow(net, sk, &fl6, final_p);
293 tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row;
298 err = inet_bhash2_update_saddr(sk, saddr, AF_INET6);
303 /* set the source address */
305 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
307 sk->sk_gso_type = SKB_GSO_TCPV6;
308 ip6_dst_store(sk, dst, NULL, NULL);
310 icsk->icsk_ext_hdr_len = 0;
312 icsk->icsk_ext_hdr_len = opt->opt_flen +
315 tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
317 inet->inet_dport = usin->sin6_port;
319 tcp_set_state(sk, TCP_SYN_SENT);
320 err = inet6_hash_connect(tcp_death_row, sk);
326 if (likely(!tp->repair)) {
328 WRITE_ONCE(tp->write_seq,
329 secure_tcpv6_seq(np->saddr.s6_addr32,
330 sk->sk_v6_daddr.s6_addr32,
333 tp->tsoffset = secure_tcpv6_ts_off(net, np->saddr.s6_addr32,
334 sk->sk_v6_daddr.s6_addr32);
337 if (tcp_fastopen_defer_connect(sk, &err))
342 err = tcp_connect(sk);
349 tcp_set_state(sk, TCP_CLOSE);
350 inet_bhash2_reset_saddr(sk);
352 inet->inet_dport = 0;
353 sk->sk_route_caps = 0;
357 static void tcp_v6_mtu_reduced(struct sock *sk)
359 struct dst_entry *dst;
362 if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
365 mtu = READ_ONCE(tcp_sk(sk)->mtu_info);
367 /* Drop requests trying to increase our current mss.
368 * Check done in __ip6_rt_update_pmtu() is too late.
370 if (tcp_mtu_to_mss(sk, mtu) >= tcp_sk(sk)->mss_cache)
373 dst = inet6_csk_update_pmtu(sk, mtu);
377 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
378 tcp_sync_mss(sk, dst_mtu(dst));
379 tcp_simple_retransmit(sk);
383 static int tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
384 u8 type, u8 code, int offset, __be32 info)
386 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
387 const struct tcphdr *th = (struct tcphdr *)(skb->data+offset);
388 struct net *net = dev_net(skb->dev);
389 struct request_sock *fastopen;
390 struct ipv6_pinfo *np;
397 sk = __inet6_lookup_established(net, net->ipv4.tcp_death_row.hashinfo,
398 &hdr->daddr, th->dest,
399 &hdr->saddr, ntohs(th->source),
400 skb->dev->ifindex, inet6_sdif(skb));
403 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
408 if (sk->sk_state == TCP_TIME_WAIT) {
409 inet_twsk_put(inet_twsk(sk));
412 seq = ntohl(th->seq);
413 fatal = icmpv6_err_convert(type, code, &err);
414 if (sk->sk_state == TCP_NEW_SYN_RECV) {
415 tcp_req_err(sk, seq, fatal);
420 if (sock_owned_by_user(sk) && type != ICMPV6_PKT_TOOBIG)
421 __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS);
423 if (sk->sk_state == TCP_CLOSE)
426 if (static_branch_unlikely(&ip6_min_hopcount)) {
427 /* min_hopcount can be changed concurrently from do_ipv6_setsockopt() */
428 if (ipv6_hdr(skb)->hop_limit < READ_ONCE(tcp_inet6_sk(sk)->min_hopcount)) {
429 __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP);
435 /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */
436 fastopen = rcu_dereference(tp->fastopen_rsk);
437 snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una;
438 if (sk->sk_state != TCP_LISTEN &&
439 !between(seq, snd_una, tp->snd_nxt)) {
440 __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS);
444 np = tcp_inet6_sk(sk);
446 if (type == NDISC_REDIRECT) {
447 if (!sock_owned_by_user(sk)) {
448 struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);
451 dst->ops->redirect(dst, sk, skb);
456 if (type == ICMPV6_PKT_TOOBIG) {
457 u32 mtu = ntohl(info);
459 /* We are not interested in TCP_LISTEN and open_requests
460 * (SYN-ACKs send out by Linux are always <576bytes so
461 * they should go through unfragmented).
463 if (sk->sk_state == TCP_LISTEN)
466 if (!ip6_sk_accept_pmtu(sk))
469 if (mtu < IPV6_MIN_MTU)
472 WRITE_ONCE(tp->mtu_info, mtu);
474 if (!sock_owned_by_user(sk))
475 tcp_v6_mtu_reduced(sk);
476 else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED,
483 /* Might be for an request_sock */
484 switch (sk->sk_state) {
487 /* Only in fast or simultaneous open. If a fast open socket is
488 * already accepted it is treated as a connected one below.
490 if (fastopen && !fastopen->sk)
493 ipv6_icmp_error(sk, skb, err, th->dest, ntohl(info), (u8 *)th);
495 if (!sock_owned_by_user(sk)) {
497 sk_error_report(sk); /* Wake people up to see the error (see connect in sock.c) */
501 sk->sk_err_soft = err;
506 /* check if this ICMP message allows revert of backoff.
509 if (!fastopen && type == ICMPV6_DEST_UNREACH &&
510 code == ICMPV6_NOROUTE)
511 tcp_ld_RTO_revert(sk, seq);
514 if (!sock_owned_by_user(sk) && np->recverr) {
518 sk->sk_err_soft = err;
527 static int tcp_v6_send_synack(const struct sock *sk, struct dst_entry *dst,
529 struct request_sock *req,
530 struct tcp_fastopen_cookie *foc,
531 enum tcp_synack_type synack_type,
532 struct sk_buff *syn_skb)
534 struct inet_request_sock *ireq = inet_rsk(req);
535 struct ipv6_pinfo *np = tcp_inet6_sk(sk);
536 struct ipv6_txoptions *opt;
537 struct flowi6 *fl6 = &fl->u.ip6;
542 /* First, grab a route. */
543 if (!dst && (dst = inet6_csk_route_req(sk, fl6, req,
544 IPPROTO_TCP)) == NULL)
547 skb = tcp_make_synack(sk, dst, req, foc, synack_type, syn_skb);
550 __tcp_v6_send_check(skb, &ireq->ir_v6_loc_addr,
551 &ireq->ir_v6_rmt_addr);
553 fl6->daddr = ireq->ir_v6_rmt_addr;
554 if (np->repflow && ireq->pktopts)
555 fl6->flowlabel = ip6_flowlabel(ipv6_hdr(ireq->pktopts));
557 tclass = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reflect_tos) ?
558 (tcp_rsk(req)->syn_tos & ~INET_ECN_MASK) |
559 (np->tclass & INET_ECN_MASK) :
562 if (!INET_ECN_is_capable(tclass) &&
563 tcp_bpf_ca_needs_ecn((struct sock *)req))
564 tclass |= INET_ECN_ECT_0;
567 opt = ireq->ipv6_opt;
569 opt = rcu_dereference(np->opt);
570 err = ip6_xmit(sk, skb, fl6, skb->mark ? : READ_ONCE(sk->sk_mark),
571 opt, tclass, sk->sk_priority);
573 err = net_xmit_eval(err);
581 static void tcp_v6_reqsk_destructor(struct request_sock *req)
583 kfree(inet_rsk(req)->ipv6_opt);
584 consume_skb(inet_rsk(req)->pktopts);
587 #ifdef CONFIG_TCP_MD5SIG
588 static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(const struct sock *sk,
589 const struct in6_addr *addr,
592 return tcp_md5_do_lookup(sk, l3index,
593 (union tcp_md5_addr *)addr, AF_INET6);
596 static struct tcp_md5sig_key *tcp_v6_md5_lookup(const struct sock *sk,
597 const struct sock *addr_sk)
601 l3index = l3mdev_master_ifindex_by_index(sock_net(sk),
602 addr_sk->sk_bound_dev_if);
603 return tcp_v6_md5_do_lookup(sk, &addr_sk->sk_v6_daddr,
607 static int tcp_v6_parse_md5_keys(struct sock *sk, int optname,
608 sockptr_t optval, int optlen)
610 struct tcp_md5sig cmd;
611 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr;
616 if (optlen < sizeof(cmd))
619 if (copy_from_sockptr(&cmd, optval, sizeof(cmd)))
622 if (sin6->sin6_family != AF_INET6)
625 flags = cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX;
627 if (optname == TCP_MD5SIG_EXT &&
628 cmd.tcpm_flags & TCP_MD5SIG_FLAG_PREFIX) {
629 prefixlen = cmd.tcpm_prefixlen;
630 if (prefixlen > 128 || (ipv6_addr_v4mapped(&sin6->sin6_addr) &&
634 prefixlen = ipv6_addr_v4mapped(&sin6->sin6_addr) ? 32 : 128;
637 if (optname == TCP_MD5SIG_EXT && cmd.tcpm_ifindex &&
638 cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX) {
639 struct net_device *dev;
642 dev = dev_get_by_index_rcu(sock_net(sk), cmd.tcpm_ifindex);
643 if (dev && netif_is_l3_master(dev))
644 l3index = dev->ifindex;
647 /* ok to reference set/not set outside of rcu;
648 * right now device MUST be an L3 master
650 if (!dev || !l3index)
654 if (!cmd.tcpm_keylen) {
655 if (ipv6_addr_v4mapped(&sin6->sin6_addr))
656 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3],
659 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr,
660 AF_INET6, prefixlen, l3index, flags);
663 if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN)
666 if (ipv6_addr_v4mapped(&sin6->sin6_addr))
667 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3],
668 AF_INET, prefixlen, l3index, flags,
669 cmd.tcpm_key, cmd.tcpm_keylen,
672 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin6->sin6_addr,
673 AF_INET6, prefixlen, l3index, flags,
674 cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL);
677 static int tcp_v6_md5_hash_headers(struct tcp_md5sig_pool *hp,
678 const struct in6_addr *daddr,
679 const struct in6_addr *saddr,
680 const struct tcphdr *th, int nbytes)
682 struct tcp6_pseudohdr *bp;
683 struct scatterlist sg;
687 /* 1. TCP pseudo-header (RFC2460) */
690 bp->protocol = cpu_to_be32(IPPROTO_TCP);
691 bp->len = cpu_to_be32(nbytes);
693 _th = (struct tcphdr *)(bp + 1);
694 memcpy(_th, th, sizeof(*th));
697 sg_init_one(&sg, bp, sizeof(*bp) + sizeof(*th));
698 ahash_request_set_crypt(hp->md5_req, &sg, NULL,
699 sizeof(*bp) + sizeof(*th));
700 return crypto_ahash_update(hp->md5_req);
703 static int tcp_v6_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key,
704 const struct in6_addr *daddr, struct in6_addr *saddr,
705 const struct tcphdr *th)
707 struct tcp_md5sig_pool *hp;
708 struct ahash_request *req;
710 hp = tcp_get_md5sig_pool();
712 goto clear_hash_noput;
715 if (crypto_ahash_init(req))
717 if (tcp_v6_md5_hash_headers(hp, daddr, saddr, th, th->doff << 2))
719 if (tcp_md5_hash_key(hp, key))
721 ahash_request_set_crypt(req, NULL, md5_hash, 0);
722 if (crypto_ahash_final(req))
725 tcp_put_md5sig_pool();
729 tcp_put_md5sig_pool();
731 memset(md5_hash, 0, 16);
735 static int tcp_v6_md5_hash_skb(char *md5_hash,
736 const struct tcp_md5sig_key *key,
737 const struct sock *sk,
738 const struct sk_buff *skb)
740 const struct in6_addr *saddr, *daddr;
741 struct tcp_md5sig_pool *hp;
742 struct ahash_request *req;
743 const struct tcphdr *th = tcp_hdr(skb);
745 if (sk) { /* valid for establish/request sockets */
746 saddr = &sk->sk_v6_rcv_saddr;
747 daddr = &sk->sk_v6_daddr;
749 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
750 saddr = &ip6h->saddr;
751 daddr = &ip6h->daddr;
754 hp = tcp_get_md5sig_pool();
756 goto clear_hash_noput;
759 if (crypto_ahash_init(req))
762 if (tcp_v6_md5_hash_headers(hp, daddr, saddr, th, skb->len))
764 if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2))
766 if (tcp_md5_hash_key(hp, key))
768 ahash_request_set_crypt(req, NULL, md5_hash, 0);
769 if (crypto_ahash_final(req))
772 tcp_put_md5sig_pool();
776 tcp_put_md5sig_pool();
778 memset(md5_hash, 0, 16);
784 static void tcp_v6_init_req(struct request_sock *req,
785 const struct sock *sk_listener,
788 bool l3_slave = ipv6_l3mdev_skb(TCP_SKB_CB(skb)->header.h6.flags);
789 struct inet_request_sock *ireq = inet_rsk(req);
790 const struct ipv6_pinfo *np = tcp_inet6_sk(sk_listener);
792 ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
793 ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
795 /* So that link locals have meaning */
796 if ((!sk_listener->sk_bound_dev_if || l3_slave) &&
797 ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
798 ireq->ir_iif = tcp_v6_iif(skb);
800 if (!TCP_SKB_CB(skb)->tcp_tw_isn &&
801 (ipv6_opt_accepted(sk_listener, skb, &TCP_SKB_CB(skb)->header.h6) ||
802 np->rxopt.bits.rxinfo ||
803 np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim ||
804 np->rxopt.bits.rxohlim || np->repflow)) {
805 refcount_inc(&skb->users);
810 static struct dst_entry *tcp_v6_route_req(const struct sock *sk,
813 struct request_sock *req)
815 tcp_v6_init_req(req, sk, skb);
817 if (security_inet_conn_request(sk, skb, req))
820 return inet6_csk_route_req(sk, &fl->u.ip6, req, IPPROTO_TCP);
823 struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
825 .obj_size = sizeof(struct tcp6_request_sock),
826 .rtx_syn_ack = tcp_rtx_synack,
827 .send_ack = tcp_v6_reqsk_send_ack,
828 .destructor = tcp_v6_reqsk_destructor,
829 .send_reset = tcp_v6_send_reset,
830 .syn_ack_timeout = tcp_syn_ack_timeout,
833 const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
834 .mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) -
835 sizeof(struct ipv6hdr),
836 #ifdef CONFIG_TCP_MD5SIG
837 .req_md5_lookup = tcp_v6_md5_lookup,
838 .calc_md5_hash = tcp_v6_md5_hash_skb,
840 #ifdef CONFIG_SYN_COOKIES
841 .cookie_init_seq = cookie_v6_init_sequence,
843 .route_req = tcp_v6_route_req,
844 .init_seq = tcp_v6_init_seq,
845 .init_ts_off = tcp_v6_init_ts_off,
846 .send_synack = tcp_v6_send_synack,
849 static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 seq,
850 u32 ack, u32 win, u32 tsval, u32 tsecr,
851 int oif, struct tcp_md5sig_key *key, int rst,
852 u8 tclass, __be32 label, u32 priority, u32 txhash)
854 const struct tcphdr *th = tcp_hdr(skb);
856 struct sk_buff *buff;
858 struct net *net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev);
859 struct sock *ctl_sk = net->ipv6.tcp_sk;
860 unsigned int tot_len = sizeof(struct tcphdr);
861 __be32 mrst = 0, *topt;
862 struct dst_entry *dst;
866 tot_len += TCPOLEN_TSTAMP_ALIGNED;
867 #ifdef CONFIG_TCP_MD5SIG
869 tot_len += TCPOLEN_MD5SIG_ALIGNED;
874 mrst = mptcp_reset_option(skb);
877 tot_len += sizeof(__be32);
881 buff = alloc_skb(MAX_TCP_HEADER, GFP_ATOMIC);
885 skb_reserve(buff, MAX_TCP_HEADER);
887 t1 = skb_push(buff, tot_len);
888 skb_reset_transport_header(buff);
890 /* Swap the send and the receive. */
891 memset(t1, 0, sizeof(*t1));
892 t1->dest = th->source;
893 t1->source = th->dest;
894 t1->doff = tot_len / 4;
895 t1->seq = htonl(seq);
896 t1->ack_seq = htonl(ack);
897 t1->ack = !rst || !th->ack;
899 t1->window = htons(win);
901 topt = (__be32 *)(t1 + 1);
904 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
905 (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
906 *topt++ = htonl(tsval);
907 *topt++ = htonl(tsecr);
913 #ifdef CONFIG_TCP_MD5SIG
915 *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
916 (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG);
917 tcp_v6_md5_hash_hdr((__u8 *)topt, key,
918 &ipv6_hdr(skb)->saddr,
919 &ipv6_hdr(skb)->daddr, t1);
923 memset(&fl6, 0, sizeof(fl6));
924 fl6.daddr = ipv6_hdr(skb)->saddr;
925 fl6.saddr = ipv6_hdr(skb)->daddr;
926 fl6.flowlabel = label;
928 buff->ip_summed = CHECKSUM_PARTIAL;
930 __tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr);
932 fl6.flowi6_proto = IPPROTO_TCP;
933 if (rt6_need_strict(&fl6.daddr) && !oif)
934 fl6.flowi6_oif = tcp_v6_iif(skb);
936 if (!oif && netif_index_is_l3_master(net, skb->skb_iif))
939 fl6.flowi6_oif = oif;
943 if (sk->sk_state == TCP_TIME_WAIT)
944 mark = inet_twsk(sk)->tw_mark;
946 mark = READ_ONCE(sk->sk_mark);
947 skb_set_delivery_time(buff, tcp_transmit_time(sk), true);
950 /* autoflowlabel/skb_get_hash_flowi6 rely on buff->hash */
951 skb_set_hash(buff, txhash, PKT_HASH_TYPE_L4);
953 fl6.flowi6_mark = IP6_REPLY_MARK(net, skb->mark) ?: mark;
954 fl6.fl6_dport = t1->dest;
955 fl6.fl6_sport = t1->source;
956 fl6.flowi6_uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL);
957 security_skb_classify_flow(skb, flowi6_to_flowi_common(&fl6));
959 /* Pass a socket to ip6_dst_lookup either it is for RST
960 * Underlying function will use this to retrieve the network
963 if (sk && sk->sk_state != TCP_TIME_WAIT)
964 dst = ip6_dst_lookup_flow(net, sk, &fl6, NULL); /*sk's xfrm_policy can be referred*/
966 dst = ip6_dst_lookup_flow(net, ctl_sk, &fl6, NULL);
968 skb_dst_set(buff, dst);
969 ip6_xmit(ctl_sk, buff, &fl6, fl6.flowi6_mark, NULL,
970 tclass & ~INET_ECN_MASK, priority);
971 TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
973 TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
980 static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb)
982 const struct tcphdr *th = tcp_hdr(skb);
983 struct ipv6hdr *ipv6h = ipv6_hdr(skb);
984 u32 seq = 0, ack_seq = 0;
985 struct tcp_md5sig_key *key = NULL;
986 #ifdef CONFIG_TCP_MD5SIG
987 const __u8 *hash_location = NULL;
988 unsigned char newhash[16];
990 struct sock *sk1 = NULL;
1001 /* If sk not NULL, it means we did a successful lookup and incoming
1002 * route had to be correct. prequeue might have dropped our dst.
1004 if (!sk && !ipv6_unicast_destination(skb))
1007 net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev);
1008 #ifdef CONFIG_TCP_MD5SIG
1010 hash_location = tcp_parse_md5sig_option(th);
1011 if (sk && sk_fullsock(sk)) {
1014 /* sdif set, means packet ingressed via a device
1015 * in an L3 domain and inet_iif is set to it.
1017 l3index = tcp_v6_sdif(skb) ? tcp_v6_iif_l3_slave(skb) : 0;
1018 key = tcp_v6_md5_do_lookup(sk, &ipv6h->saddr, l3index);
1019 } else if (hash_location) {
1020 int dif = tcp_v6_iif_l3_slave(skb);
1021 int sdif = tcp_v6_sdif(skb);
1025 * active side is lost. Try to find listening socket through
1026 * source port, and then find md5 key through listening socket.
1027 * we are not loose security here:
1028 * Incoming packet is checked with md5 hash with finding key,
1029 * no RST generated if md5 hash doesn't match.
1031 sk1 = inet6_lookup_listener(net, net->ipv4.tcp_death_row.hashinfo,
1032 NULL, 0, &ipv6h->saddr, th->source,
1033 &ipv6h->daddr, ntohs(th->source),
1038 /* sdif set, means packet ingressed via a device
1039 * in an L3 domain and dif is set to it.
1041 l3index = tcp_v6_sdif(skb) ? dif : 0;
1043 key = tcp_v6_md5_do_lookup(sk1, &ipv6h->saddr, l3index);
1047 genhash = tcp_v6_md5_hash_skb(newhash, key, NULL, skb);
1048 if (genhash || memcmp(hash_location, newhash, 16) != 0)
1054 seq = ntohl(th->ack_seq);
1056 ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len -
1060 oif = sk->sk_bound_dev_if;
1061 if (sk_fullsock(sk)) {
1062 const struct ipv6_pinfo *np = tcp_inet6_sk(sk);
1064 trace_tcp_send_reset(sk, skb);
1066 label = ip6_flowlabel(ipv6h);
1067 priority = sk->sk_priority;
1068 txhash = sk->sk_txhash;
1070 if (sk->sk_state == TCP_TIME_WAIT) {
1071 label = cpu_to_be32(inet_twsk(sk)->tw_flowlabel);
1072 priority = inet_twsk(sk)->tw_priority;
1073 txhash = inet_twsk(sk)->tw_txhash;
1076 if (net->ipv6.sysctl.flowlabel_reflect & FLOWLABEL_REFLECT_TCP_RESET)
1077 label = ip6_flowlabel(ipv6h);
1080 tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1,
1081 ipv6_get_dsfield(ipv6h), label, priority, txhash);
1083 #ifdef CONFIG_TCP_MD5SIG
1089 static void tcp_v6_send_ack(const struct sock *sk, struct sk_buff *skb, u32 seq,
1090 u32 ack, u32 win, u32 tsval, u32 tsecr, int oif,
1091 struct tcp_md5sig_key *key, u8 tclass,
1092 __be32 label, u32 priority, u32 txhash)
1094 tcp_v6_send_response(sk, skb, seq, ack, win, tsval, tsecr, oif, key, 0,
1095 tclass, label, priority, txhash);
1098 static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
1100 struct inet_timewait_sock *tw = inet_twsk(sk);
1101 struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
1103 tcp_v6_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
1104 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
1105 tcp_time_stamp_raw() + tcptw->tw_ts_offset,
1106 tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw),
1107 tw->tw_tclass, cpu_to_be32(tw->tw_flowlabel), tw->tw_priority,
1113 static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
1114 struct request_sock *req)
1118 l3index = tcp_v6_sdif(skb) ? tcp_v6_iif_l3_slave(skb) : 0;
1120 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV
1121 * sk->sk_state == TCP_SYN_RECV -> for Fast Open.
1124 * The window field (SEG.WND) of every outgoing segment, with the
1125 * exception of <SYN> segments, MUST be right-shifted by
1126 * Rcv.Wind.Shift bits:
1128 tcp_v6_send_ack(sk, skb, (sk->sk_state == TCP_LISTEN) ?
1129 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt,
1130 tcp_rsk(req)->rcv_nxt,
1131 req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale,
1132 tcp_time_stamp_raw() + tcp_rsk(req)->ts_off,
1133 READ_ONCE(req->ts_recent), sk->sk_bound_dev_if,
1134 tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->saddr, l3index),
1135 ipv6_get_dsfield(ipv6_hdr(skb)), 0,
1136 READ_ONCE(sk->sk_priority),
1137 READ_ONCE(tcp_rsk(req)->txhash));
1141 static struct sock *tcp_v6_cookie_check(struct sock *sk, struct sk_buff *skb)
1143 #ifdef CONFIG_SYN_COOKIES
1144 const struct tcphdr *th = tcp_hdr(skb);
1147 sk = cookie_v6_check(sk, skb);
1152 u16 tcp_v6_get_syncookie(struct sock *sk, struct ipv6hdr *iph,
1153 struct tcphdr *th, u32 *cookie)
1156 #ifdef CONFIG_SYN_COOKIES
1157 mss = tcp_get_syncookie_mss(&tcp6_request_sock_ops,
1158 &tcp_request_sock_ipv6_ops, sk, th);
1160 *cookie = __cookie_v6_init_sequence(iph, th, &mss);
1161 tcp_synq_overflow(sk);
1167 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
1169 if (skb->protocol == htons(ETH_P_IP))
1170 return tcp_v4_conn_request(sk, skb);
1172 if (!ipv6_unicast_destination(skb))
1175 if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
1176 __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
1180 return tcp_conn_request(&tcp6_request_sock_ops,
1181 &tcp_request_sock_ipv6_ops, sk, skb);
1185 return 0; /* don't send reset */
1188 static void tcp_v6_restore_cb(struct sk_buff *skb)
1190 /* We need to move header back to the beginning if xfrm6_policy_check()
1191 * and tcp_v6_fill_cb() are going to be called again.
1192 * ip6_datagram_recv_specific_ctl() also expects IP6CB to be there.
1194 memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6,
1195 sizeof(struct inet6_skb_parm));
1198 static struct sock *tcp_v6_syn_recv_sock(const struct sock *sk, struct sk_buff *skb,
1199 struct request_sock *req,
1200 struct dst_entry *dst,
1201 struct request_sock *req_unhash,
1204 struct inet_request_sock *ireq;
1205 struct ipv6_pinfo *newnp;
1206 const struct ipv6_pinfo *np = tcp_inet6_sk(sk);
1207 struct ipv6_txoptions *opt;
1208 struct inet_sock *newinet;
1209 bool found_dup_sk = false;
1210 struct tcp_sock *newtp;
1212 #ifdef CONFIG_TCP_MD5SIG
1213 struct tcp_md5sig_key *key;
1218 if (skb->protocol == htons(ETH_P_IP)) {
1223 newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst,
1224 req_unhash, own_req);
1229 inet_sk(newsk)->pinet6 = tcp_inet6_sk(newsk);
1231 newnp = tcp_inet6_sk(newsk);
1232 newtp = tcp_sk(newsk);
1234 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1236 newnp->saddr = newsk->sk_v6_rcv_saddr;
1238 inet_csk(newsk)->icsk_af_ops = &ipv6_mapped;
1239 if (sk_is_mptcp(newsk))
1240 mptcpv6_handle_mapped(newsk, true);
1241 newsk->sk_backlog_rcv = tcp_v4_do_rcv;
1242 #ifdef CONFIG_TCP_MD5SIG
1243 newtp->af_specific = &tcp_sock_ipv6_mapped_specific;
1246 newnp->ipv6_mc_list = NULL;
1247 newnp->ipv6_ac_list = NULL;
1248 newnp->ipv6_fl_list = NULL;
1249 newnp->pktoptions = NULL;
1251 newnp->mcast_oif = inet_iif(skb);
1252 newnp->mcast_hops = ip_hdr(skb)->ttl;
1253 newnp->rcv_flowinfo = 0;
1255 newnp->flow_label = 0;
1258 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
1259 * here, tcp_create_openreq_child now does this for us, see the comment in
1260 * that function for the gory details. -acme
1263 /* It is tricky place. Until this moment IPv4 tcp
1264 worked with IPv6 icsk.icsk_af_ops.
1267 tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
1272 ireq = inet_rsk(req);
1274 if (sk_acceptq_is_full(sk))
1278 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_TCP);
1283 newsk = tcp_create_openreq_child(sk, req, skb);
1288 * No need to charge this sock to the relevant IPv6 refcnt debug socks
1289 * count here, tcp_create_openreq_child now does this for us, see the
1290 * comment in that function for the gory details. -acme
1293 newsk->sk_gso_type = SKB_GSO_TCPV6;
1294 ip6_dst_store(newsk, dst, NULL, NULL);
1295 inet6_sk_rx_dst_set(newsk, skb);
1297 inet_sk(newsk)->pinet6 = tcp_inet6_sk(newsk);
1299 newtp = tcp_sk(newsk);
1300 newinet = inet_sk(newsk);
1301 newnp = tcp_inet6_sk(newsk);
1303 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
1305 newsk->sk_v6_daddr = ireq->ir_v6_rmt_addr;
1306 newnp->saddr = ireq->ir_v6_loc_addr;
1307 newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr;
1308 newsk->sk_bound_dev_if = ireq->ir_iif;
1310 /* Now IPv6 options...
1312 First: no IPv4 options.
1314 newinet->inet_opt = NULL;
1315 newnp->ipv6_mc_list = NULL;
1316 newnp->ipv6_ac_list = NULL;
1317 newnp->ipv6_fl_list = NULL;
1320 newnp->rxopt.all = np->rxopt.all;
1322 newnp->pktoptions = NULL;
1324 newnp->mcast_oif = tcp_v6_iif(skb);
1325 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
1326 newnp->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(skb));
1328 newnp->flow_label = ip6_flowlabel(ipv6_hdr(skb));
1330 /* Set ToS of the new socket based upon the value of incoming SYN.
1331 * ECT bits are set later in tcp_init_transfer().
1333 if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_reflect_tos))
1334 newnp->tclass = tcp_rsk(req)->syn_tos & ~INET_ECN_MASK;
1336 /* Clone native IPv6 options from listening socket (if any)
1338 Yes, keeping reference count would be much more clever,
1339 but we make one more one thing there: reattach optmem
1342 opt = ireq->ipv6_opt;
1344 opt = rcu_dereference(np->opt);
1346 opt = ipv6_dup_options(newsk, opt);
1347 RCU_INIT_POINTER(newnp->opt, opt);
1349 inet_csk(newsk)->icsk_ext_hdr_len = 0;
1351 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen +
1354 tcp_ca_openreq_child(newsk, dst);
1356 tcp_sync_mss(newsk, dst_mtu(dst));
1357 newtp->advmss = tcp_mss_clamp(tcp_sk(sk), dst_metric_advmss(dst));
1359 tcp_initialize_rcv_mss(newsk);
1361 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
1362 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
1364 #ifdef CONFIG_TCP_MD5SIG
1365 l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif);
1367 /* Copy over the MD5 key from the original socket */
1368 key = tcp_v6_md5_do_lookup(sk, &newsk->sk_v6_daddr, l3index);
1370 /* We're using one, so create a matching key
1371 * on the newsk structure. If we fail to get
1372 * memory, then we end up not copying the key
1375 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newsk->sk_v6_daddr,
1376 AF_INET6, 128, l3index, key->flags, key->key, key->keylen,
1377 sk_gfp_mask(sk, GFP_ATOMIC));
1381 if (__inet_inherit_port(sk, newsk) < 0) {
1382 inet_csk_prepare_forced_close(newsk);
1386 *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash),
1389 tcp_move_syn(newtp, req);
1391 /* Clone pktoptions received with SYN, if we own the req */
1392 if (ireq->pktopts) {
1393 newnp->pktoptions = skb_clone_and_charge_r(ireq->pktopts, newsk);
1394 consume_skb(ireq->pktopts);
1395 ireq->pktopts = NULL;
1396 if (newnp->pktoptions)
1397 tcp_v6_restore_cb(newnp->pktoptions);
1400 if (!req_unhash && found_dup_sk) {
1401 /* This code path should only be executed in the
1402 * syncookie case only
1404 bh_unlock_sock(newsk);
1413 __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
1421 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
1423 /* The socket must have it's spinlock held when we get
1424 * here, unless it is a TCP_LISTEN socket.
1426 * We have a potential double-lock case here, so even when
1427 * doing backlog processing we use the BH locking scheme.
1428 * This is because we cannot sleep with the original spinlock
1431 INDIRECT_CALLABLE_SCOPE
1432 int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
1434 struct ipv6_pinfo *np = tcp_inet6_sk(sk);
1435 struct sk_buff *opt_skb = NULL;
1436 enum skb_drop_reason reason;
1437 struct tcp_sock *tp;
1439 /* Imagine: socket is IPv6. IPv4 packet arrives,
1440 goes to IPv4 receive handler and backlogged.
1441 From backlog it always goes here. Kerboom...
1442 Fortunately, tcp_rcv_established and rcv_established
1443 handle them correctly, but it is not case with
1444 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK
1447 if (skb->protocol == htons(ETH_P_IP))
1448 return tcp_v4_do_rcv(sk, skb);
1451 * socket locking is here for SMP purposes as backlog rcv
1452 * is currently called with bh processing disabled.
1455 /* Do Stevens' IPV6_PKTOPTIONS.
1457 Yes, guys, it is the only place in our code, where we
1458 may make it not affecting IPv4.
1459 The rest of code is protocol independent,
1460 and I do not like idea to uglify IPv4.
1462 Actually, all the idea behind IPV6_PKTOPTIONS
1463 looks not very well thought. For now we latch
1464 options, received in the last packet, enqueued
1465 by tcp. Feel free to propose better solution.
1469 opt_skb = skb_clone_and_charge_r(skb, sk);
1471 reason = SKB_DROP_REASON_NOT_SPECIFIED;
1472 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
1473 struct dst_entry *dst;
1475 dst = rcu_dereference_protected(sk->sk_rx_dst,
1476 lockdep_sock_is_held(sk));
1478 sock_rps_save_rxhash(sk, skb);
1479 sk_mark_napi_id(sk, skb);
1481 if (sk->sk_rx_dst_ifindex != skb->skb_iif ||
1482 INDIRECT_CALL_1(dst->ops->check, ip6_dst_check,
1483 dst, sk->sk_rx_dst_cookie) == NULL) {
1484 RCU_INIT_POINTER(sk->sk_rx_dst, NULL);
1489 tcp_rcv_established(sk, skb);
1491 goto ipv6_pktoptions;
1495 if (tcp_checksum_complete(skb))
1498 if (sk->sk_state == TCP_LISTEN) {
1499 struct sock *nsk = tcp_v6_cookie_check(sk, skb);
1505 if (tcp_child_process(sk, nsk, skb))
1508 __kfree_skb(opt_skb);
1512 sock_rps_save_rxhash(sk, skb);
1514 if (tcp_rcv_state_process(sk, skb))
1517 goto ipv6_pktoptions;
1521 tcp_v6_send_reset(sk, skb);
1524 __kfree_skb(opt_skb);
1525 kfree_skb_reason(skb, reason);
1528 reason = SKB_DROP_REASON_TCP_CSUM;
1529 trace_tcp_bad_csum(skb);
1530 TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
1531 TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
1536 /* Do you ask, what is it?
1538 1. skb was enqueued by tcp.
1539 2. skb is added to tail of read queue, rather than out of order.
1540 3. socket is not in passive state.
1541 4. Finally, it really contains options, which user wants to receive.
1544 if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt &&
1545 !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) {
1546 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
1547 np->mcast_oif = tcp_v6_iif(opt_skb);
1548 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
1549 np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit;
1550 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass)
1551 np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb));
1553 np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb));
1554 if (ipv6_opt_accepted(sk, opt_skb, &TCP_SKB_CB(opt_skb)->header.h6)) {
1555 tcp_v6_restore_cb(opt_skb);
1556 opt_skb = xchg(&np->pktoptions, opt_skb);
1558 __kfree_skb(opt_skb);
1559 opt_skb = xchg(&np->pktoptions, NULL);
1563 consume_skb(opt_skb);
1567 static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr,
1568 const struct tcphdr *th)
1570 /* This is tricky: we move IP6CB at its correct location into
1571 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because
1572 * _decode_session6() uses IP6CB().
1573 * barrier() makes sure compiler won't play aliasing games.
1575 memmove(&TCP_SKB_CB(skb)->header.h6, IP6CB(skb),
1576 sizeof(struct inet6_skb_parm));
1579 TCP_SKB_CB(skb)->seq = ntohl(th->seq);
1580 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
1581 skb->len - th->doff*4);
1582 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
1583 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th);
1584 TCP_SKB_CB(skb)->tcp_tw_isn = 0;
1585 TCP_SKB_CB(skb)->ip_dsfield = ipv6_get_dsfield(hdr);
1586 TCP_SKB_CB(skb)->sacked = 0;
1587 TCP_SKB_CB(skb)->has_rxtstamp =
1588 skb->tstamp || skb_hwtstamps(skb)->hwtstamp;
1591 INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
1593 enum skb_drop_reason drop_reason;
1594 int sdif = inet6_sdif(skb);
1595 int dif = inet6_iif(skb);
1596 const struct tcphdr *th;
1597 const struct ipv6hdr *hdr;
1601 struct net *net = dev_net(skb->dev);
1603 drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
1604 if (skb->pkt_type != PACKET_HOST)
1608 * Count it even if it's bad.
1610 __TCP_INC_STATS(net, TCP_MIB_INSEGS);
1612 if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
1615 th = (const struct tcphdr *)skb->data;
1617 if (unlikely(th->doff < sizeof(struct tcphdr) / 4)) {
1618 drop_reason = SKB_DROP_REASON_PKT_TOO_SMALL;
1621 if (!pskb_may_pull(skb, th->doff*4))
1624 if (skb_checksum_init(skb, IPPROTO_TCP, ip6_compute_pseudo))
1627 th = (const struct tcphdr *)skb->data;
1628 hdr = ipv6_hdr(skb);
1631 sk = __inet6_lookup_skb(net->ipv4.tcp_death_row.hashinfo, skb, __tcp_hdrlen(th),
1632 th->source, th->dest, inet6_iif(skb), sdif,
1638 if (sk->sk_state == TCP_TIME_WAIT)
1641 if (sk->sk_state == TCP_NEW_SYN_RECV) {
1642 struct request_sock *req = inet_reqsk(sk);
1643 bool req_stolen = false;
1646 sk = req->rsk_listener;
1647 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
1648 drop_reason = SKB_DROP_REASON_XFRM_POLICY;
1650 drop_reason = tcp_inbound_md5_hash(sk, skb,
1651 &hdr->saddr, &hdr->daddr,
1652 AF_INET6, dif, sdif);
1654 sk_drops_add(sk, skb);
1658 if (tcp_checksum_complete(skb)) {
1662 if (unlikely(sk->sk_state != TCP_LISTEN)) {
1663 nsk = reuseport_migrate_sock(sk, req_to_sk(req), skb);
1665 inet_csk_reqsk_queue_drop_and_put(sk, req);
1669 /* reuseport_migrate_sock() has already held one sk_refcnt
1677 if (!tcp_filter(sk, skb)) {
1678 th = (const struct tcphdr *)skb->data;
1679 hdr = ipv6_hdr(skb);
1680 tcp_v6_fill_cb(skb, hdr, th);
1681 nsk = tcp_check_req(sk, skb, req, false, &req_stolen);
1683 drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
1688 /* Another cpu got exclusive access to req
1689 * and created a full blown socket.
1690 * Try to feed this packet to this socket
1691 * instead of discarding it.
1693 tcp_v6_restore_cb(skb);
1697 goto discard_and_relse;
1702 tcp_v6_restore_cb(skb);
1703 } else if (tcp_child_process(sk, nsk, skb)) {
1704 tcp_v6_send_reset(nsk, skb);
1705 goto discard_and_relse;
1712 if (static_branch_unlikely(&ip6_min_hopcount)) {
1713 /* min_hopcount can be changed concurrently from do_ipv6_setsockopt() */
1714 if (hdr->hop_limit < READ_ONCE(tcp_inet6_sk(sk)->min_hopcount)) {
1715 __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP);
1716 goto discard_and_relse;
1720 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
1721 drop_reason = SKB_DROP_REASON_XFRM_POLICY;
1722 goto discard_and_relse;
1725 drop_reason = tcp_inbound_md5_hash(sk, skb, &hdr->saddr, &hdr->daddr,
1726 AF_INET6, dif, sdif);
1728 goto discard_and_relse;
1732 if (tcp_filter(sk, skb)) {
1733 drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
1734 goto discard_and_relse;
1736 th = (const struct tcphdr *)skb->data;
1737 hdr = ipv6_hdr(skb);
1738 tcp_v6_fill_cb(skb, hdr, th);
1742 if (sk->sk_state == TCP_LISTEN) {
1743 ret = tcp_v6_do_rcv(sk, skb);
1744 goto put_and_return;
1747 sk_incoming_cpu_update(sk);
1749 bh_lock_sock_nested(sk);
1750 tcp_segs_in(tcp_sk(sk), skb);
1752 if (!sock_owned_by_user(sk)) {
1753 ret = tcp_v6_do_rcv(sk, skb);
1755 if (tcp_add_backlog(sk, skb, &drop_reason))
1756 goto discard_and_relse;
1762 return ret ? -1 : 0;
1765 drop_reason = SKB_DROP_REASON_NO_SOCKET;
1766 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
1769 tcp_v6_fill_cb(skb, hdr, th);
1771 if (tcp_checksum_complete(skb)) {
1773 drop_reason = SKB_DROP_REASON_TCP_CSUM;
1774 trace_tcp_bad_csum(skb);
1775 __TCP_INC_STATS(net, TCP_MIB_CSUMERRORS);
1777 __TCP_INC_STATS(net, TCP_MIB_INERRS);
1779 tcp_v6_send_reset(NULL, skb);
1783 SKB_DR_OR(drop_reason, NOT_SPECIFIED);
1784 kfree_skb_reason(skb, drop_reason);
1788 sk_drops_add(sk, skb);
1794 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
1795 drop_reason = SKB_DROP_REASON_XFRM_POLICY;
1796 inet_twsk_put(inet_twsk(sk));
1800 tcp_v6_fill_cb(skb, hdr, th);
1802 if (tcp_checksum_complete(skb)) {
1803 inet_twsk_put(inet_twsk(sk));
1807 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) {
1812 sk2 = inet6_lookup_listener(net, net->ipv4.tcp_death_row.hashinfo,
1813 skb, __tcp_hdrlen(th),
1814 &ipv6_hdr(skb)->saddr, th->source,
1815 &ipv6_hdr(skb)->daddr,
1817 tcp_v6_iif_l3_slave(skb),
1820 struct inet_timewait_sock *tw = inet_twsk(sk);
1821 inet_twsk_deschedule_put(tw);
1823 tcp_v6_restore_cb(skb);
1831 tcp_v6_timewait_ack(sk, skb);
1834 tcp_v6_send_reset(sk, skb);
1835 inet_twsk_deschedule_put(inet_twsk(sk));
1837 case TCP_TW_SUCCESS:
1843 void tcp_v6_early_demux(struct sk_buff *skb)
1845 struct net *net = dev_net(skb->dev);
1846 const struct ipv6hdr *hdr;
1847 const struct tcphdr *th;
1850 if (skb->pkt_type != PACKET_HOST)
1853 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr)))
1856 hdr = ipv6_hdr(skb);
1859 if (th->doff < sizeof(struct tcphdr) / 4)
1862 /* Note : We use inet6_iif() here, not tcp_v6_iif() */
1863 sk = __inet6_lookup_established(net, net->ipv4.tcp_death_row.hashinfo,
1864 &hdr->saddr, th->source,
1865 &hdr->daddr, ntohs(th->dest),
1866 inet6_iif(skb), inet6_sdif(skb));
1869 skb->destructor = sock_edemux;
1870 if (sk_fullsock(sk)) {
1871 struct dst_entry *dst = rcu_dereference(sk->sk_rx_dst);
1874 dst = dst_check(dst, sk->sk_rx_dst_cookie);
1876 sk->sk_rx_dst_ifindex == skb->skb_iif)
1877 skb_dst_set_noref(skb, dst);
1882 static struct timewait_sock_ops tcp6_timewait_sock_ops = {
1883 .twsk_obj_size = sizeof(struct tcp6_timewait_sock),
1884 .twsk_unique = tcp_twsk_unique,
1885 .twsk_destructor = tcp_twsk_destructor,
1888 INDIRECT_CALLABLE_SCOPE void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb)
1890 __tcp_v6_send_check(skb, &sk->sk_v6_rcv_saddr, &sk->sk_v6_daddr);
1893 const struct inet_connection_sock_af_ops ipv6_specific = {
1894 .queue_xmit = inet6_csk_xmit,
1895 .send_check = tcp_v6_send_check,
1896 .rebuild_header = inet6_sk_rebuild_header,
1897 .sk_rx_dst_set = inet6_sk_rx_dst_set,
1898 .conn_request = tcp_v6_conn_request,
1899 .syn_recv_sock = tcp_v6_syn_recv_sock,
1900 .net_header_len = sizeof(struct ipv6hdr),
1901 .net_frag_header_len = sizeof(struct frag_hdr),
1902 .setsockopt = ipv6_setsockopt,
1903 .getsockopt = ipv6_getsockopt,
1904 .addr2sockaddr = inet6_csk_addr2sockaddr,
1905 .sockaddr_len = sizeof(struct sockaddr_in6),
1906 .mtu_reduced = tcp_v6_mtu_reduced,
1909 #ifdef CONFIG_TCP_MD5SIG
1910 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = {
1911 .md5_lookup = tcp_v6_md5_lookup,
1912 .calc_md5_hash = tcp_v6_md5_hash_skb,
1913 .md5_parse = tcp_v6_parse_md5_keys,
1918 * TCP over IPv4 via INET6 API
1920 static const struct inet_connection_sock_af_ops ipv6_mapped = {
1921 .queue_xmit = ip_queue_xmit,
1922 .send_check = tcp_v4_send_check,
1923 .rebuild_header = inet_sk_rebuild_header,
1924 .sk_rx_dst_set = inet_sk_rx_dst_set,
1925 .conn_request = tcp_v6_conn_request,
1926 .syn_recv_sock = tcp_v6_syn_recv_sock,
1927 .net_header_len = sizeof(struct iphdr),
1928 .setsockopt = ipv6_setsockopt,
1929 .getsockopt = ipv6_getsockopt,
1930 .addr2sockaddr = inet6_csk_addr2sockaddr,
1931 .sockaddr_len = sizeof(struct sockaddr_in6),
1932 .mtu_reduced = tcp_v4_mtu_reduced,
1935 #ifdef CONFIG_TCP_MD5SIG
1936 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = {
1937 .md5_lookup = tcp_v4_md5_lookup,
1938 .calc_md5_hash = tcp_v4_md5_hash_skb,
1939 .md5_parse = tcp_v6_parse_md5_keys,
1943 /* NOTE: A lot of things set to zero explicitly by call to
1944 * sk_alloc() so need not be done here.
1946 static int tcp_v6_init_sock(struct sock *sk)
1948 struct inet_connection_sock *icsk = inet_csk(sk);
1952 icsk->icsk_af_ops = &ipv6_specific;
1954 #ifdef CONFIG_TCP_MD5SIG
1955 tcp_sk(sk)->af_specific = &tcp_sock_ipv6_specific;
1961 #ifdef CONFIG_PROC_FS
1962 /* Proc filesystem TCPv6 sock list dumping. */
1963 static void get_openreq6(struct seq_file *seq,
1964 const struct request_sock *req, int i)
1966 long ttd = req->rsk_timer.expires - jiffies;
1967 const struct in6_addr *src = &inet_rsk(req)->ir_v6_loc_addr;
1968 const struct in6_addr *dest = &inet_rsk(req)->ir_v6_rmt_addr;
1974 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1975 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n",
1977 src->s6_addr32[0], src->s6_addr32[1],
1978 src->s6_addr32[2], src->s6_addr32[3],
1979 inet_rsk(req)->ir_num,
1980 dest->s6_addr32[0], dest->s6_addr32[1],
1981 dest->s6_addr32[2], dest->s6_addr32[3],
1982 ntohs(inet_rsk(req)->ir_rmt_port),
1984 0, 0, /* could print option size, but that is af dependent. */
1985 1, /* timers active (only the expire timer) */
1986 jiffies_to_clock_t(ttd),
1988 from_kuid_munged(seq_user_ns(seq),
1989 sock_i_uid(req->rsk_listener)),
1990 0, /* non standard timer */
1991 0, /* open_requests have no inode */
1995 static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
1997 const struct in6_addr *dest, *src;
2000 unsigned long timer_expires;
2001 const struct inet_sock *inet = inet_sk(sp);
2002 const struct tcp_sock *tp = tcp_sk(sp);
2003 const struct inet_connection_sock *icsk = inet_csk(sp);
2004 const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq;
2008 dest = &sp->sk_v6_daddr;
2009 src = &sp->sk_v6_rcv_saddr;
2010 destp = ntohs(inet->inet_dport);
2011 srcp = ntohs(inet->inet_sport);
2013 if (icsk->icsk_pending == ICSK_TIME_RETRANS ||
2014 icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT ||
2015 icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
2017 timer_expires = icsk->icsk_timeout;
2018 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
2020 timer_expires = icsk->icsk_timeout;
2021 } else if (timer_pending(&sp->sk_timer)) {
2023 timer_expires = sp->sk_timer.expires;
2026 timer_expires = jiffies;
2029 state = inet_sk_state_load(sp);
2030 if (state == TCP_LISTEN)
2031 rx_queue = READ_ONCE(sp->sk_ack_backlog);
2033 /* Because we don't lock the socket,
2034 * we might find a transient negative value.
2036 rx_queue = max_t(int, READ_ONCE(tp->rcv_nxt) -
2037 READ_ONCE(tp->copied_seq), 0);
2040 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
2041 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n",
2043 src->s6_addr32[0], src->s6_addr32[1],
2044 src->s6_addr32[2], src->s6_addr32[3], srcp,
2045 dest->s6_addr32[0], dest->s6_addr32[1],
2046 dest->s6_addr32[2], dest->s6_addr32[3], destp,
2048 READ_ONCE(tp->write_seq) - tp->snd_una,
2051 jiffies_delta_to_clock_t(timer_expires - jiffies),
2052 icsk->icsk_retransmits,
2053 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
2054 icsk->icsk_probes_out,
2056 refcount_read(&sp->sk_refcnt), sp,
2057 jiffies_to_clock_t(icsk->icsk_rto),
2058 jiffies_to_clock_t(icsk->icsk_ack.ato),
2059 (icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(sp),
2061 state == TCP_LISTEN ?
2062 fastopenq->max_qlen :
2063 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh)
2067 static void get_timewait6_sock(struct seq_file *seq,
2068 struct inet_timewait_sock *tw, int i)
2070 long delta = tw->tw_timer.expires - jiffies;
2071 const struct in6_addr *dest, *src;
2074 dest = &tw->tw_v6_daddr;
2075 src = &tw->tw_v6_rcv_saddr;
2076 destp = ntohs(tw->tw_dport);
2077 srcp = ntohs(tw->tw_sport);
2080 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
2081 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
2083 src->s6_addr32[0], src->s6_addr32[1],
2084 src->s6_addr32[2], src->s6_addr32[3], srcp,
2085 dest->s6_addr32[0], dest->s6_addr32[1],
2086 dest->s6_addr32[2], dest->s6_addr32[3], destp,
2087 tw->tw_substate, 0, 0,
2088 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0,
2089 refcount_read(&tw->tw_refcnt), tw);
2092 static int tcp6_seq_show(struct seq_file *seq, void *v)
2094 struct tcp_iter_state *st;
2095 struct sock *sk = v;
2097 if (v == SEQ_START_TOKEN) {
2102 "st tx_queue rx_queue tr tm->when retrnsmt"
2103 " uid timeout inode\n");
2108 if (sk->sk_state == TCP_TIME_WAIT)
2109 get_timewait6_sock(seq, v, st->num);
2110 else if (sk->sk_state == TCP_NEW_SYN_RECV)
2111 get_openreq6(seq, v, st->num);
2113 get_tcp6_sock(seq, v, st->num);
2118 static const struct seq_operations tcp6_seq_ops = {
2119 .show = tcp6_seq_show,
2120 .start = tcp_seq_start,
2121 .next = tcp_seq_next,
2122 .stop = tcp_seq_stop,
2125 static struct tcp_seq_afinfo tcp6_seq_afinfo = {
2129 int __net_init tcp6_proc_init(struct net *net)
2131 if (!proc_create_net_data("tcp6", 0444, net->proc_net, &tcp6_seq_ops,
2132 sizeof(struct tcp_iter_state), &tcp6_seq_afinfo))
2137 void tcp6_proc_exit(struct net *net)
2139 remove_proc_entry("tcp6", net->proc_net);
2143 struct proto tcpv6_prot = {
2145 .owner = THIS_MODULE,
2147 .pre_connect = tcp_v6_pre_connect,
2148 .connect = tcp_v6_connect,
2149 .disconnect = tcp_disconnect,
2150 .accept = inet_csk_accept,
2152 .init = tcp_v6_init_sock,
2153 .destroy = tcp_v4_destroy_sock,
2154 .shutdown = tcp_shutdown,
2155 .setsockopt = tcp_setsockopt,
2156 .getsockopt = tcp_getsockopt,
2157 .bpf_bypass_getsockopt = tcp_bpf_bypass_getsockopt,
2158 .keepalive = tcp_set_keepalive,
2159 .recvmsg = tcp_recvmsg,
2160 .sendmsg = tcp_sendmsg,
2161 .splice_eof = tcp_splice_eof,
2162 .sendpage = tcp_sendpage,
2163 .backlog_rcv = tcp_v6_do_rcv,
2164 .release_cb = tcp_release_cb,
2166 .unhash = inet_unhash,
2167 .get_port = inet_csk_get_port,
2168 .put_port = inet_put_port,
2169 #ifdef CONFIG_BPF_SYSCALL
2170 .psock_update_sk_prot = tcp_bpf_update_proto,
2172 .enter_memory_pressure = tcp_enter_memory_pressure,
2173 .leave_memory_pressure = tcp_leave_memory_pressure,
2174 .stream_memory_free = tcp_stream_memory_free,
2175 .sockets_allocated = &tcp_sockets_allocated,
2177 .memory_allocated = &tcp_memory_allocated,
2178 .per_cpu_fw_alloc = &tcp_memory_per_cpu_fw_alloc,
2180 .memory_pressure = &tcp_memory_pressure,
2181 .orphan_count = &tcp_orphan_count,
2182 .sysctl_mem = sysctl_tcp_mem,
2183 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_tcp_wmem),
2184 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_tcp_rmem),
2185 .max_header = MAX_TCP_HEADER,
2186 .obj_size = sizeof(struct tcp6_sock),
2187 .slab_flags = SLAB_TYPESAFE_BY_RCU,
2188 .twsk_prot = &tcp6_timewait_sock_ops,
2189 .rsk_prot = &tcp6_request_sock_ops,
2191 .no_autobind = true,
2192 .diag_destroy = tcp_abort,
2194 EXPORT_SYMBOL_GPL(tcpv6_prot);
2196 static const struct inet6_protocol tcpv6_protocol = {
2197 .handler = tcp_v6_rcv,
2198 .err_handler = tcp_v6_err,
2199 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
2202 static struct inet_protosw tcpv6_protosw = {
2203 .type = SOCK_STREAM,
2204 .protocol = IPPROTO_TCP,
2205 .prot = &tcpv6_prot,
2206 .ops = &inet6_stream_ops,
2207 .flags = INET_PROTOSW_PERMANENT |
2211 static int __net_init tcpv6_net_init(struct net *net)
2213 return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6,
2214 SOCK_RAW, IPPROTO_TCP, net);
2217 static void __net_exit tcpv6_net_exit(struct net *net)
2219 inet_ctl_sock_destroy(net->ipv6.tcp_sk);
2222 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list)
2224 tcp_twsk_purge(net_exit_list, AF_INET6);
2227 static struct pernet_operations tcpv6_net_ops = {
2228 .init = tcpv6_net_init,
2229 .exit = tcpv6_net_exit,
2230 .exit_batch = tcpv6_net_exit_batch,
2233 int __init tcpv6_init(void)
2237 ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP);
2241 /* register inet6 protocol */
2242 ret = inet6_register_protosw(&tcpv6_protosw);
2244 goto out_tcpv6_protocol;
2246 ret = register_pernet_subsys(&tcpv6_net_ops);
2248 goto out_tcpv6_protosw;
2250 ret = mptcpv6_init();
2252 goto out_tcpv6_pernet_subsys;
2257 out_tcpv6_pernet_subsys:
2258 unregister_pernet_subsys(&tcpv6_net_ops);
2260 inet6_unregister_protosw(&tcpv6_protosw);
2262 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP);
2266 void tcpv6_exit(void)
2268 unregister_pernet_subsys(&tcpv6_net_ops);
2269 inet6_unregister_protosw(&tcpv6_protosw);
2270 inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP);