3 * Linux INET6 implementation
6 * Pedro Roque <roque@di.fc.ul.pt>
10 * linux/net/ipv4/tcp_input.c
11 * linux/net/ipv4/tcp_output.c
14 * Hideaki YOSHIFUJI : sin6_scope_id support
15 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
16 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
17 * a single port at the same time.
18 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/tcp6 to seq_file.
20 * This program is free software; you can redistribute it and/or
21 * modify it under the terms of the GNU General Public License
22 * as published by the Free Software Foundation; either version
23 * 2 of the License, or (at your option) any later version.
26 #include <linux/bottom_half.h>
27 #include <linux/module.h>
28 #include <linux/errno.h>
29 #include <linux/types.h>
30 #include <linux/socket.h>
31 #include <linux/sockios.h>
32 #include <linux/net.h>
33 #include <linux/jiffies.h>
35 #include <linux/in6.h>
36 #include <linux/netdevice.h>
37 #include <linux/init.h>
38 #include <linux/jhash.h>
39 #include <linux/ipsec.h>
40 #include <linux/times.h>
41 #include <linux/slab.h>
42 #include <linux/uaccess.h>
43 #include <linux/ipv6.h>
44 #include <linux/icmpv6.h>
45 #include <linux/random.h>
48 #include <net/ndisc.h>
49 #include <net/inet6_hashtables.h>
50 #include <net/inet6_connection_sock.h>
52 #include <net/transp_v6.h>
53 #include <net/addrconf.h>
54 #include <net/ip6_route.h>
55 #include <net/ip6_checksum.h>
56 #include <net/inet_ecn.h>
57 #include <net/protocol.h>
60 #include <net/dsfield.h>
61 #include <net/timewait_sock.h>
62 #include <net/inet_common.h>
63 #include <net/secure_seq.h>
64 #include <net/busy_poll.h>
66 #include <linux/proc_fs.h>
67 #include <linux/seq_file.h>
69 #include <crypto/hash.h>
70 #include <linux/scatterlist.h>
72 static void tcp_v6_send_reset(const struct sock
*sk
, struct sk_buff
*skb
);
73 static void tcp_v6_reqsk_send_ack(const struct sock
*sk
, struct sk_buff
*skb
,
74 struct request_sock
*req
);
76 static int tcp_v6_do_rcv(struct sock
*sk
, struct sk_buff
*skb
);
78 static const struct inet_connection_sock_af_ops ipv6_mapped
;
79 static const struct inet_connection_sock_af_ops ipv6_specific
;
80 #ifdef CONFIG_TCP_MD5SIG
81 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific
;
82 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific
;
84 static struct tcp_md5sig_key
*tcp_v6_md5_do_lookup(const struct sock
*sk
,
85 const struct in6_addr
*addr
)
91 static void inet6_sk_rx_dst_set(struct sock
*sk
, const struct sk_buff
*skb
)
93 struct dst_entry
*dst
= skb_dst(skb
);
95 if (dst
&& dst_hold_safe(dst
)) {
96 const struct rt6_info
*rt
= (const struct rt6_info
*)dst
;
99 inet_sk(sk
)->rx_dst_ifindex
= skb
->skb_iif
;
100 inet6_sk(sk
)->rx_dst_cookie
= rt6_get_cookie(rt
);
104 static __u32
tcp_v6_init_sequence(const struct sk_buff
*skb
)
106 return secure_tcpv6_sequence_number(ipv6_hdr(skb
)->daddr
.s6_addr32
,
107 ipv6_hdr(skb
)->saddr
.s6_addr32
,
109 tcp_hdr(skb
)->source
);
112 static int tcp_v6_connect(struct sock
*sk
, struct sockaddr
*uaddr
,
115 struct sockaddr_in6
*usin
= (struct sockaddr_in6
*) uaddr
;
116 struct inet_sock
*inet
= inet_sk(sk
);
117 struct inet_connection_sock
*icsk
= inet_csk(sk
);
118 struct ipv6_pinfo
*np
= inet6_sk(sk
);
119 struct tcp_sock
*tp
= tcp_sk(sk
);
120 struct in6_addr
*saddr
= NULL
, *final_p
, final
;
121 struct ipv6_txoptions
*opt
;
123 struct dst_entry
*dst
;
127 if (addr_len
< SIN6_LEN_RFC2133
)
130 if (usin
->sin6_family
!= AF_INET6
)
131 return -EAFNOSUPPORT
;
133 memset(&fl6
, 0, sizeof(fl6
));
136 fl6
.flowlabel
= usin
->sin6_flowinfo
&IPV6_FLOWINFO_MASK
;
137 IP6_ECN_flow_init(fl6
.flowlabel
);
138 if (fl6
.flowlabel
&IPV6_FLOWLABEL_MASK
) {
139 struct ip6_flowlabel
*flowlabel
;
140 flowlabel
= fl6_sock_lookup(sk
, fl6
.flowlabel
);
143 fl6_sock_release(flowlabel
);
148 * connect() to INADDR_ANY means loopback (BSD'ism).
151 if (ipv6_addr_any(&usin
->sin6_addr
))
152 usin
->sin6_addr
.s6_addr
[15] = 0x1;
154 addr_type
= ipv6_addr_type(&usin
->sin6_addr
);
156 if (addr_type
& IPV6_ADDR_MULTICAST
)
159 if (addr_type
&IPV6_ADDR_LINKLOCAL
) {
160 if (addr_len
>= sizeof(struct sockaddr_in6
) &&
161 usin
->sin6_scope_id
) {
162 /* If interface is set while binding, indices
165 if (sk
->sk_bound_dev_if
&&
166 sk
->sk_bound_dev_if
!= usin
->sin6_scope_id
)
169 sk
->sk_bound_dev_if
= usin
->sin6_scope_id
;
172 /* Connect to link-local address requires an interface */
173 if (!sk
->sk_bound_dev_if
)
177 if (tp
->rx_opt
.ts_recent_stamp
&&
178 !ipv6_addr_equal(&sk
->sk_v6_daddr
, &usin
->sin6_addr
)) {
179 tp
->rx_opt
.ts_recent
= 0;
180 tp
->rx_opt
.ts_recent_stamp
= 0;
184 sk
->sk_v6_daddr
= usin
->sin6_addr
;
185 np
->flow_label
= fl6
.flowlabel
;
191 if (addr_type
== IPV6_ADDR_MAPPED
) {
192 u32 exthdrlen
= icsk
->icsk_ext_hdr_len
;
193 struct sockaddr_in sin
;
195 SOCK_DEBUG(sk
, "connect: ipv4 mapped\n");
197 if (__ipv6_only_sock(sk
))
200 sin
.sin_family
= AF_INET
;
201 sin
.sin_port
= usin
->sin6_port
;
202 sin
.sin_addr
.s_addr
= usin
->sin6_addr
.s6_addr32
[3];
204 icsk
->icsk_af_ops
= &ipv6_mapped
;
205 sk
->sk_backlog_rcv
= tcp_v4_do_rcv
;
206 #ifdef CONFIG_TCP_MD5SIG
207 tp
->af_specific
= &tcp_sock_ipv6_mapped_specific
;
210 err
= tcp_v4_connect(sk
, (struct sockaddr
*)&sin
, sizeof(sin
));
213 icsk
->icsk_ext_hdr_len
= exthdrlen
;
214 icsk
->icsk_af_ops
= &ipv6_specific
;
215 sk
->sk_backlog_rcv
= tcp_v6_do_rcv
;
216 #ifdef CONFIG_TCP_MD5SIG
217 tp
->af_specific
= &tcp_sock_ipv6_specific
;
221 np
->saddr
= sk
->sk_v6_rcv_saddr
;
226 if (!ipv6_addr_any(&sk
->sk_v6_rcv_saddr
))
227 saddr
= &sk
->sk_v6_rcv_saddr
;
229 fl6
.flowi6_proto
= IPPROTO_TCP
;
230 fl6
.daddr
= sk
->sk_v6_daddr
;
231 fl6
.saddr
= saddr
? *saddr
: np
->saddr
;
232 fl6
.flowi6_oif
= sk
->sk_bound_dev_if
;
233 fl6
.flowi6_mark
= sk
->sk_mark
;
234 fl6
.fl6_dport
= usin
->sin6_port
;
235 fl6
.fl6_sport
= inet
->inet_sport
;
237 opt
= rcu_dereference_protected(np
->opt
, lockdep_sock_is_held(sk
));
238 final_p
= fl6_update_dst(&fl6
, opt
, &final
);
240 security_sk_classify_flow(sk
, flowi6_to_flowi(&fl6
));
242 dst
= ip6_dst_lookup_flow(sk
, &fl6
, final_p
);
250 sk
->sk_v6_rcv_saddr
= *saddr
;
253 /* set the source address */
255 inet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
257 sk
->sk_gso_type
= SKB_GSO_TCPV6
;
258 ip6_dst_store(sk
, dst
, NULL
, NULL
);
260 if (tcp_death_row
.sysctl_tw_recycle
&&
261 !tp
->rx_opt
.ts_recent_stamp
&&
262 ipv6_addr_equal(&fl6
.daddr
, &sk
->sk_v6_daddr
))
263 tcp_fetch_timewait_stamp(sk
, dst
);
265 icsk
->icsk_ext_hdr_len
= 0;
267 icsk
->icsk_ext_hdr_len
= opt
->opt_flen
+
270 tp
->rx_opt
.mss_clamp
= IPV6_MIN_MTU
- sizeof(struct tcphdr
) - sizeof(struct ipv6hdr
);
272 inet
->inet_dport
= usin
->sin6_port
;
274 tcp_set_state(sk
, TCP_SYN_SENT
);
275 err
= inet6_hash_connect(&tcp_death_row
, sk
);
281 if (!tp
->write_seq
&& likely(!tp
->repair
))
282 tp
->write_seq
= secure_tcpv6_sequence_number(np
->saddr
.s6_addr32
,
283 sk
->sk_v6_daddr
.s6_addr32
,
287 err
= tcp_connect(sk
);
294 tcp_set_state(sk
, TCP_CLOSE
);
297 inet
->inet_dport
= 0;
298 sk
->sk_route_caps
= 0;
302 static void tcp_v6_mtu_reduced(struct sock
*sk
)
304 struct dst_entry
*dst
;
306 if ((1 << sk
->sk_state
) & (TCPF_LISTEN
| TCPF_CLOSE
))
309 dst
= inet6_csk_update_pmtu(sk
, tcp_sk(sk
)->mtu_info
);
313 if (inet_csk(sk
)->icsk_pmtu_cookie
> dst_mtu(dst
)) {
314 tcp_sync_mss(sk
, dst_mtu(dst
));
315 tcp_simple_retransmit(sk
);
319 static void tcp_v6_err(struct sk_buff
*skb
, struct inet6_skb_parm
*opt
,
320 u8 type
, u8 code
, int offset
, __be32 info
)
322 const struct ipv6hdr
*hdr
= (const struct ipv6hdr
*)skb
->data
;
323 const struct tcphdr
*th
= (struct tcphdr
*)(skb
->data
+offset
);
324 struct net
*net
= dev_net(skb
->dev
);
325 struct request_sock
*fastopen
;
326 struct ipv6_pinfo
*np
;
333 sk
= __inet6_lookup_established(net
, &tcp_hashinfo
,
334 &hdr
->daddr
, th
->dest
,
335 &hdr
->saddr
, ntohs(th
->source
),
339 __ICMP6_INC_STATS(net
, __in6_dev_get(skb
->dev
),
344 if (sk
->sk_state
== TCP_TIME_WAIT
) {
345 inet_twsk_put(inet_twsk(sk
));
348 seq
= ntohl(th
->seq
);
349 fatal
= icmpv6_err_convert(type
, code
, &err
);
350 if (sk
->sk_state
== TCP_NEW_SYN_RECV
)
351 return tcp_req_err(sk
, seq
, fatal
);
354 if (sock_owned_by_user(sk
) && type
!= ICMPV6_PKT_TOOBIG
)
355 __NET_INC_STATS(net
, LINUX_MIB_LOCKDROPPEDICMPS
);
357 if (sk
->sk_state
== TCP_CLOSE
)
360 if (ipv6_hdr(skb
)->hop_limit
< inet6_sk(sk
)->min_hopcount
) {
361 __NET_INC_STATS(net
, LINUX_MIB_TCPMINTTLDROP
);
366 /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */
367 fastopen
= tp
->fastopen_rsk
;
368 snd_una
= fastopen
? tcp_rsk(fastopen
)->snt_isn
: tp
->snd_una
;
369 if (sk
->sk_state
!= TCP_LISTEN
&&
370 !between(seq
, snd_una
, tp
->snd_nxt
)) {
371 __NET_INC_STATS(net
, LINUX_MIB_OUTOFWINDOWICMPS
);
377 if (type
== NDISC_REDIRECT
) {
378 struct dst_entry
*dst
= __sk_dst_check(sk
, np
->dst_cookie
);
381 dst
->ops
->redirect(dst
, sk
, skb
);
385 if (type
== ICMPV6_PKT_TOOBIG
) {
386 /* We are not interested in TCP_LISTEN and open_requests
387 * (SYN-ACKs send out by Linux are always <576bytes so
388 * they should go through unfragmented).
390 if (sk
->sk_state
== TCP_LISTEN
)
393 if (!ip6_sk_accept_pmtu(sk
))
396 tp
->mtu_info
= ntohl(info
);
397 if (!sock_owned_by_user(sk
))
398 tcp_v6_mtu_reduced(sk
);
399 else if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED
,
406 /* Might be for an request_sock */
407 switch (sk
->sk_state
) {
410 /* Only in fast or simultaneous open. If a fast open socket is
411 * is already accepted it is treated as a connected one below.
413 if (fastopen
&& !fastopen
->sk
)
416 if (!sock_owned_by_user(sk
)) {
418 sk
->sk_error_report(sk
); /* Wake people up to see the error (see connect in sock.c) */
422 sk
->sk_err_soft
= err
;
426 if (!sock_owned_by_user(sk
) && np
->recverr
) {
428 sk
->sk_error_report(sk
);
430 sk
->sk_err_soft
= err
;
438 static int tcp_v6_send_synack(const struct sock
*sk
, struct dst_entry
*dst
,
440 struct request_sock
*req
,
441 struct tcp_fastopen_cookie
*foc
,
442 enum tcp_synack_type synack_type
)
444 struct inet_request_sock
*ireq
= inet_rsk(req
);
445 struct ipv6_pinfo
*np
= inet6_sk(sk
);
446 struct ipv6_txoptions
*opt
;
447 struct flowi6
*fl6
= &fl
->u
.ip6
;
451 /* First, grab a route. */
452 if (!dst
&& (dst
= inet6_csk_route_req(sk
, fl6
, req
,
453 IPPROTO_TCP
)) == NULL
)
456 skb
= tcp_make_synack(sk
, dst
, req
, foc
, synack_type
);
459 __tcp_v6_send_check(skb
, &ireq
->ir_v6_loc_addr
,
460 &ireq
->ir_v6_rmt_addr
);
462 fl6
->daddr
= ireq
->ir_v6_rmt_addr
;
463 if (np
->repflow
&& ireq
->pktopts
)
464 fl6
->flowlabel
= ip6_flowlabel(ipv6_hdr(ireq
->pktopts
));
467 opt
= ireq
->ipv6_opt
;
469 opt
= rcu_dereference(np
->opt
);
470 err
= ip6_xmit(sk
, skb
, fl6
, opt
, np
->tclass
);
472 err
= net_xmit_eval(err
);
480 static void tcp_v6_reqsk_destructor(struct request_sock
*req
)
482 kfree(inet_rsk(req
)->ipv6_opt
);
483 kfree_skb(inet_rsk(req
)->pktopts
);
486 #ifdef CONFIG_TCP_MD5SIG
487 static struct tcp_md5sig_key
*tcp_v6_md5_do_lookup(const struct sock
*sk
,
488 const struct in6_addr
*addr
)
490 return tcp_md5_do_lookup(sk
, (union tcp_md5_addr
*)addr
, AF_INET6
);
493 static struct tcp_md5sig_key
*tcp_v6_md5_lookup(const struct sock
*sk
,
494 const struct sock
*addr_sk
)
496 return tcp_v6_md5_do_lookup(sk
, &addr_sk
->sk_v6_daddr
);
499 static int tcp_v6_parse_md5_keys(struct sock
*sk
, char __user
*optval
,
502 struct tcp_md5sig cmd
;
503 struct sockaddr_in6
*sin6
= (struct sockaddr_in6
*)&cmd
.tcpm_addr
;
505 if (optlen
< sizeof(cmd
))
508 if (copy_from_user(&cmd
, optval
, sizeof(cmd
)))
511 if (sin6
->sin6_family
!= AF_INET6
)
514 if (!cmd
.tcpm_keylen
) {
515 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
516 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
518 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
522 if (cmd
.tcpm_keylen
> TCP_MD5SIG_MAXKEYLEN
)
525 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
526 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
527 AF_INET
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
529 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
530 AF_INET6
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
533 static int tcp_v6_md5_hash_headers(struct tcp_md5sig_pool
*hp
,
534 const struct in6_addr
*daddr
,
535 const struct in6_addr
*saddr
,
536 const struct tcphdr
*th
, int nbytes
)
538 struct tcp6_pseudohdr
*bp
;
539 struct scatterlist sg
;
543 /* 1. TCP pseudo-header (RFC2460) */
546 bp
->protocol
= cpu_to_be32(IPPROTO_TCP
);
547 bp
->len
= cpu_to_be32(nbytes
);
549 _th
= (struct tcphdr
*)(bp
+ 1);
550 memcpy(_th
, th
, sizeof(*th
));
553 sg_init_one(&sg
, bp
, sizeof(*bp
) + sizeof(*th
));
554 ahash_request_set_crypt(hp
->md5_req
, &sg
, NULL
,
555 sizeof(*bp
) + sizeof(*th
));
556 return crypto_ahash_update(hp
->md5_req
);
559 static int tcp_v6_md5_hash_hdr(char *md5_hash
, const struct tcp_md5sig_key
*key
,
560 const struct in6_addr
*daddr
, struct in6_addr
*saddr
,
561 const struct tcphdr
*th
)
563 struct tcp_md5sig_pool
*hp
;
564 struct ahash_request
*req
;
566 hp
= tcp_get_md5sig_pool();
568 goto clear_hash_noput
;
571 if (crypto_ahash_init(req
))
573 if (tcp_v6_md5_hash_headers(hp
, daddr
, saddr
, th
, th
->doff
<< 2))
575 if (tcp_md5_hash_key(hp
, key
))
577 ahash_request_set_crypt(req
, NULL
, md5_hash
, 0);
578 if (crypto_ahash_final(req
))
581 tcp_put_md5sig_pool();
585 tcp_put_md5sig_pool();
587 memset(md5_hash
, 0, 16);
591 static int tcp_v6_md5_hash_skb(char *md5_hash
,
592 const struct tcp_md5sig_key
*key
,
593 const struct sock
*sk
,
594 const struct sk_buff
*skb
)
596 const struct in6_addr
*saddr
, *daddr
;
597 struct tcp_md5sig_pool
*hp
;
598 struct ahash_request
*req
;
599 const struct tcphdr
*th
= tcp_hdr(skb
);
601 if (sk
) { /* valid for establish/request sockets */
602 saddr
= &sk
->sk_v6_rcv_saddr
;
603 daddr
= &sk
->sk_v6_daddr
;
605 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
606 saddr
= &ip6h
->saddr
;
607 daddr
= &ip6h
->daddr
;
610 hp
= tcp_get_md5sig_pool();
612 goto clear_hash_noput
;
615 if (crypto_ahash_init(req
))
618 if (tcp_v6_md5_hash_headers(hp
, daddr
, saddr
, th
, skb
->len
))
620 if (tcp_md5_hash_skb_data(hp
, skb
, th
->doff
<< 2))
622 if (tcp_md5_hash_key(hp
, key
))
624 ahash_request_set_crypt(req
, NULL
, md5_hash
, 0);
625 if (crypto_ahash_final(req
))
628 tcp_put_md5sig_pool();
632 tcp_put_md5sig_pool();
634 memset(md5_hash
, 0, 16);
640 static bool tcp_v6_inbound_md5_hash(const struct sock
*sk
,
641 const struct sk_buff
*skb
)
643 #ifdef CONFIG_TCP_MD5SIG
644 const __u8
*hash_location
= NULL
;
645 struct tcp_md5sig_key
*hash_expected
;
646 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
647 const struct tcphdr
*th
= tcp_hdr(skb
);
651 hash_expected
= tcp_v6_md5_do_lookup(sk
, &ip6h
->saddr
);
652 hash_location
= tcp_parse_md5sig_option(th
);
654 /* We've parsed the options - do we have a hash? */
655 if (!hash_expected
&& !hash_location
)
658 if (hash_expected
&& !hash_location
) {
659 NET_INC_STATS(sock_net(sk
), LINUX_MIB_TCPMD5NOTFOUND
);
663 if (!hash_expected
&& hash_location
) {
664 NET_INC_STATS(sock_net(sk
), LINUX_MIB_TCPMD5UNEXPECTED
);
668 /* check the signature */
669 genhash
= tcp_v6_md5_hash_skb(newhash
,
673 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0) {
674 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n",
675 genhash
? "failed" : "mismatch",
676 &ip6h
->saddr
, ntohs(th
->source
),
677 &ip6h
->daddr
, ntohs(th
->dest
));
684 static void tcp_v6_init_req(struct request_sock
*req
,
685 const struct sock
*sk_listener
,
688 struct inet_request_sock
*ireq
= inet_rsk(req
);
689 const struct ipv6_pinfo
*np
= inet6_sk(sk_listener
);
691 ireq
->ir_v6_rmt_addr
= ipv6_hdr(skb
)->saddr
;
692 ireq
->ir_v6_loc_addr
= ipv6_hdr(skb
)->daddr
;
694 /* So that link locals have meaning */
695 if (!sk_listener
->sk_bound_dev_if
&&
696 ipv6_addr_type(&ireq
->ir_v6_rmt_addr
) & IPV6_ADDR_LINKLOCAL
)
697 ireq
->ir_iif
= tcp_v6_iif(skb
);
699 if (!TCP_SKB_CB(skb
)->tcp_tw_isn
&&
700 (ipv6_opt_accepted(sk_listener
, skb
, &TCP_SKB_CB(skb
)->header
.h6
) ||
701 np
->rxopt
.bits
.rxinfo
||
702 np
->rxopt
.bits
.rxoinfo
|| np
->rxopt
.bits
.rxhlim
||
703 np
->rxopt
.bits
.rxohlim
|| np
->repflow
)) {
704 atomic_inc(&skb
->users
);
709 static struct dst_entry
*tcp_v6_route_req(const struct sock
*sk
,
711 const struct request_sock
*req
,
716 return inet6_csk_route_req(sk
, &fl
->u
.ip6
, req
, IPPROTO_TCP
);
719 struct request_sock_ops tcp6_request_sock_ops __read_mostly
= {
721 .obj_size
= sizeof(struct tcp6_request_sock
),
722 .rtx_syn_ack
= tcp_rtx_synack
,
723 .send_ack
= tcp_v6_reqsk_send_ack
,
724 .destructor
= tcp_v6_reqsk_destructor
,
725 .send_reset
= tcp_v6_send_reset
,
726 .syn_ack_timeout
= tcp_syn_ack_timeout
,
729 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops
= {
730 .mss_clamp
= IPV6_MIN_MTU
- sizeof(struct tcphdr
) -
731 sizeof(struct ipv6hdr
),
732 #ifdef CONFIG_TCP_MD5SIG
733 .req_md5_lookup
= tcp_v6_md5_lookup
,
734 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
736 .init_req
= tcp_v6_init_req
,
737 #ifdef CONFIG_SYN_COOKIES
738 .cookie_init_seq
= cookie_v6_init_sequence
,
740 .route_req
= tcp_v6_route_req
,
741 .init_seq
= tcp_v6_init_sequence
,
742 .send_synack
= tcp_v6_send_synack
,
745 static void tcp_v6_send_response(const struct sock
*sk
, struct sk_buff
*skb
, u32 seq
,
746 u32 ack
, u32 win
, u32 tsval
, u32 tsecr
,
747 int oif
, struct tcp_md5sig_key
*key
, int rst
,
748 u8 tclass
, __be32 label
)
750 const struct tcphdr
*th
= tcp_hdr(skb
);
752 struct sk_buff
*buff
;
754 struct net
*net
= sk
? sock_net(sk
) : dev_net(skb_dst(skb
)->dev
);
755 struct sock
*ctl_sk
= net
->ipv6
.tcp_sk
;
756 unsigned int tot_len
= sizeof(struct tcphdr
);
757 struct dst_entry
*dst
;
761 tot_len
+= TCPOLEN_TSTAMP_ALIGNED
;
762 #ifdef CONFIG_TCP_MD5SIG
764 tot_len
+= TCPOLEN_MD5SIG_ALIGNED
;
767 buff
= alloc_skb(MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
,
772 skb_reserve(buff
, MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
);
774 t1
= (struct tcphdr
*) skb_push(buff
, tot_len
);
775 skb_reset_transport_header(buff
);
777 /* Swap the send and the receive. */
778 memset(t1
, 0, sizeof(*t1
));
779 t1
->dest
= th
->source
;
780 t1
->source
= th
->dest
;
781 t1
->doff
= tot_len
/ 4;
782 t1
->seq
= htonl(seq
);
783 t1
->ack_seq
= htonl(ack
);
784 t1
->ack
= !rst
|| !th
->ack
;
786 t1
->window
= htons(win
);
788 topt
= (__be32
*)(t1
+ 1);
791 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
792 (TCPOPT_TIMESTAMP
<< 8) | TCPOLEN_TIMESTAMP
);
793 *topt
++ = htonl(tsval
);
794 *topt
++ = htonl(tsecr
);
797 #ifdef CONFIG_TCP_MD5SIG
799 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
800 (TCPOPT_MD5SIG
<< 8) | TCPOLEN_MD5SIG
);
801 tcp_v6_md5_hash_hdr((__u8
*)topt
, key
,
802 &ipv6_hdr(skb
)->saddr
,
803 &ipv6_hdr(skb
)->daddr
, t1
);
807 memset(&fl6
, 0, sizeof(fl6
));
808 fl6
.daddr
= ipv6_hdr(skb
)->saddr
;
809 fl6
.saddr
= ipv6_hdr(skb
)->daddr
;
810 fl6
.flowlabel
= label
;
812 buff
->ip_summed
= CHECKSUM_PARTIAL
;
815 __tcp_v6_send_check(buff
, &fl6
.saddr
, &fl6
.daddr
);
817 fl6
.flowi6_proto
= IPPROTO_TCP
;
818 if (rt6_need_strict(&fl6
.daddr
) && !oif
)
819 fl6
.flowi6_oif
= tcp_v6_iif(skb
);
821 if (!oif
&& netif_index_is_l3_master(net
, skb
->skb_iif
))
824 fl6
.flowi6_oif
= oif
;
827 fl6
.flowi6_mark
= IP6_REPLY_MARK(net
, skb
->mark
);
828 fl6
.fl6_dport
= t1
->dest
;
829 fl6
.fl6_sport
= t1
->source
;
830 security_skb_classify_flow(skb
, flowi6_to_flowi(&fl6
));
832 /* Pass a socket to ip6_dst_lookup either it is for RST
833 * Underlying function will use this to retrieve the network
836 dst
= ip6_dst_lookup_flow(ctl_sk
, &fl6
, NULL
);
838 skb_dst_set(buff
, dst
);
839 ip6_xmit(ctl_sk
, buff
, &fl6
, NULL
, tclass
);
840 TCP_INC_STATS(net
, TCP_MIB_OUTSEGS
);
842 TCP_INC_STATS(net
, TCP_MIB_OUTRSTS
);
849 static void tcp_v6_send_reset(const struct sock
*sk
, struct sk_buff
*skb
)
851 const struct tcphdr
*th
= tcp_hdr(skb
);
852 u32 seq
= 0, ack_seq
= 0;
853 struct tcp_md5sig_key
*key
= NULL
;
854 #ifdef CONFIG_TCP_MD5SIG
855 const __u8
*hash_location
= NULL
;
856 struct ipv6hdr
*ipv6h
= ipv6_hdr(skb
);
857 unsigned char newhash
[16];
859 struct sock
*sk1
= NULL
;
866 /* If sk not NULL, it means we did a successful lookup and incoming
867 * route had to be correct. prequeue might have dropped our dst.
869 if (!sk
&& !ipv6_unicast_destination(skb
))
872 #ifdef CONFIG_TCP_MD5SIG
874 hash_location
= tcp_parse_md5sig_option(th
);
875 if (sk
&& sk_fullsock(sk
)) {
876 key
= tcp_v6_md5_do_lookup(sk
, &ipv6h
->saddr
);
877 } else if (hash_location
) {
879 * active side is lost. Try to find listening socket through
880 * source port, and then find md5 key through listening socket.
881 * we are not loose security here:
882 * Incoming packet is checked with md5 hash with finding key,
883 * no RST generated if md5 hash doesn't match.
885 sk1
= inet6_lookup_listener(dev_net(skb_dst(skb
)->dev
),
886 &tcp_hashinfo
, NULL
, 0,
888 th
->source
, &ipv6h
->daddr
,
889 ntohs(th
->source
), tcp_v6_iif(skb
));
893 key
= tcp_v6_md5_do_lookup(sk1
, &ipv6h
->saddr
);
897 genhash
= tcp_v6_md5_hash_skb(newhash
, key
, NULL
, skb
);
898 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0)
904 seq
= ntohl(th
->ack_seq
);
906 ack_seq
= ntohl(th
->seq
) + th
->syn
+ th
->fin
+ skb
->len
-
909 oif
= sk
? sk
->sk_bound_dev_if
: 0;
910 tcp_v6_send_response(sk
, skb
, seq
, ack_seq
, 0, 0, 0, oif
, key
, 1, 0, 0);
912 #ifdef CONFIG_TCP_MD5SIG
918 static void tcp_v6_send_ack(const struct sock
*sk
, struct sk_buff
*skb
, u32 seq
,
919 u32 ack
, u32 win
, u32 tsval
, u32 tsecr
, int oif
,
920 struct tcp_md5sig_key
*key
, u8 tclass
,
923 tcp_v6_send_response(sk
, skb
, seq
, ack
, win
, tsval
, tsecr
, oif
, key
, 0,
927 static void tcp_v6_timewait_ack(struct sock
*sk
, struct sk_buff
*skb
)
929 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
930 struct tcp_timewait_sock
*tcptw
= tcp_twsk(sk
);
932 tcp_v6_send_ack(sk
, skb
, tcptw
->tw_snd_nxt
, tcptw
->tw_rcv_nxt
,
933 tcptw
->tw_rcv_wnd
>> tw
->tw_rcv_wscale
,
934 tcp_time_stamp
+ tcptw
->tw_ts_offset
,
935 tcptw
->tw_ts_recent
, tw
->tw_bound_dev_if
, tcp_twsk_md5_key(tcptw
),
936 tw
->tw_tclass
, cpu_to_be32(tw
->tw_flowlabel
));
941 static void tcp_v6_reqsk_send_ack(const struct sock
*sk
, struct sk_buff
*skb
,
942 struct request_sock
*req
)
944 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV
945 * sk->sk_state == TCP_SYN_RECV -> for Fast Open.
948 * The window field (SEG.WND) of every outgoing segment, with the
949 * exception of <SYN> segments, MUST be right-shifted by
950 * Rcv.Wind.Shift bits:
952 tcp_v6_send_ack(sk
, skb
, (sk
->sk_state
== TCP_LISTEN
) ?
953 tcp_rsk(req
)->snt_isn
+ 1 : tcp_sk(sk
)->snd_nxt
,
954 tcp_rsk(req
)->rcv_nxt
,
955 req
->rsk_rcv_wnd
>> inet_rsk(req
)->rcv_wscale
,
956 tcp_time_stamp
, req
->ts_recent
, sk
->sk_bound_dev_if
,
957 tcp_v6_md5_do_lookup(sk
, &ipv6_hdr(skb
)->daddr
),
962 static struct sock
*tcp_v6_cookie_check(struct sock
*sk
, struct sk_buff
*skb
)
964 #ifdef CONFIG_SYN_COOKIES
965 const struct tcphdr
*th
= tcp_hdr(skb
);
968 sk
= cookie_v6_check(sk
, skb
);
973 static int tcp_v6_conn_request(struct sock
*sk
, struct sk_buff
*skb
)
975 if (skb
->protocol
== htons(ETH_P_IP
))
976 return tcp_v4_conn_request(sk
, skb
);
978 if (!ipv6_unicast_destination(skb
))
981 return tcp_conn_request(&tcp6_request_sock_ops
,
982 &tcp_request_sock_ipv6_ops
, sk
, skb
);
986 return 0; /* don't send reset */
989 static struct sock
*tcp_v6_syn_recv_sock(const struct sock
*sk
, struct sk_buff
*skb
,
990 struct request_sock
*req
,
991 struct dst_entry
*dst
,
992 struct request_sock
*req_unhash
,
995 struct inet_request_sock
*ireq
;
996 struct ipv6_pinfo
*newnp
;
997 const struct ipv6_pinfo
*np
= inet6_sk(sk
);
998 struct ipv6_txoptions
*opt
;
999 struct tcp6_sock
*newtcp6sk
;
1000 struct inet_sock
*newinet
;
1001 struct tcp_sock
*newtp
;
1003 #ifdef CONFIG_TCP_MD5SIG
1004 struct tcp_md5sig_key
*key
;
1008 if (skb
->protocol
== htons(ETH_P_IP
)) {
1013 newsk
= tcp_v4_syn_recv_sock(sk
, skb
, req
, dst
,
1014 req_unhash
, own_req
);
1019 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1020 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1022 newinet
= inet_sk(newsk
);
1023 newnp
= inet6_sk(newsk
);
1024 newtp
= tcp_sk(newsk
);
1026 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1028 newnp
->saddr
= newsk
->sk_v6_rcv_saddr
;
1030 inet_csk(newsk
)->icsk_af_ops
= &ipv6_mapped
;
1031 newsk
->sk_backlog_rcv
= tcp_v4_do_rcv
;
1032 #ifdef CONFIG_TCP_MD5SIG
1033 newtp
->af_specific
= &tcp_sock_ipv6_mapped_specific
;
1036 newnp
->ipv6_ac_list
= NULL
;
1037 newnp
->ipv6_fl_list
= NULL
;
1038 newnp
->pktoptions
= NULL
;
1040 newnp
->mcast_oif
= tcp_v6_iif(skb
);
1041 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1042 newnp
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(skb
));
1044 newnp
->flow_label
= ip6_flowlabel(ipv6_hdr(skb
));
1047 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
1048 * here, tcp_create_openreq_child now does this for us, see the comment in
1049 * that function for the gory details. -acme
1052 /* It is tricky place. Until this moment IPv4 tcp
1053 worked with IPv6 icsk.icsk_af_ops.
1056 tcp_sync_mss(newsk
, inet_csk(newsk
)->icsk_pmtu_cookie
);
1061 ireq
= inet_rsk(req
);
1063 if (sk_acceptq_is_full(sk
))
1067 dst
= inet6_csk_route_req(sk
, &fl6
, req
, IPPROTO_TCP
);
1072 newsk
= tcp_create_openreq_child(sk
, req
, skb
);
1077 * No need to charge this sock to the relevant IPv6 refcnt debug socks
1078 * count here, tcp_create_openreq_child now does this for us, see the
1079 * comment in that function for the gory details. -acme
1082 newsk
->sk_gso_type
= SKB_GSO_TCPV6
;
1083 ip6_dst_store(newsk
, dst
, NULL
, NULL
);
1084 inet6_sk_rx_dst_set(newsk
, skb
);
1086 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1087 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1089 newtp
= tcp_sk(newsk
);
1090 newinet
= inet_sk(newsk
);
1091 newnp
= inet6_sk(newsk
);
1093 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1095 newsk
->sk_v6_daddr
= ireq
->ir_v6_rmt_addr
;
1096 newnp
->saddr
= ireq
->ir_v6_loc_addr
;
1097 newsk
->sk_v6_rcv_saddr
= ireq
->ir_v6_loc_addr
;
1098 newsk
->sk_bound_dev_if
= ireq
->ir_iif
;
1100 /* Now IPv6 options...
1102 First: no IPv4 options.
1104 newinet
->inet_opt
= NULL
;
1105 newnp
->ipv6_ac_list
= NULL
;
1106 newnp
->ipv6_fl_list
= NULL
;
1109 newnp
->rxopt
.all
= np
->rxopt
.all
;
1111 newnp
->pktoptions
= NULL
;
1113 newnp
->mcast_oif
= tcp_v6_iif(skb
);
1114 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1115 newnp
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(skb
));
1117 newnp
->flow_label
= ip6_flowlabel(ipv6_hdr(skb
));
1119 /* Clone native IPv6 options from listening socket (if any)
1121 Yes, keeping reference count would be much more clever,
1122 but we make one more one thing there: reattach optmem
1125 opt
= ireq
->ipv6_opt
;
1127 opt
= rcu_dereference(np
->opt
);
1129 opt
= ipv6_dup_options(newsk
, opt
);
1130 RCU_INIT_POINTER(newnp
->opt
, opt
);
1132 inet_csk(newsk
)->icsk_ext_hdr_len
= 0;
1134 inet_csk(newsk
)->icsk_ext_hdr_len
= opt
->opt_nflen
+
1137 tcp_ca_openreq_child(newsk
, dst
);
1139 tcp_sync_mss(newsk
, dst_mtu(dst
));
1140 newtp
->advmss
= dst_metric_advmss(dst
);
1141 if (tcp_sk(sk
)->rx_opt
.user_mss
&&
1142 tcp_sk(sk
)->rx_opt
.user_mss
< newtp
->advmss
)
1143 newtp
->advmss
= tcp_sk(sk
)->rx_opt
.user_mss
;
1145 tcp_initialize_rcv_mss(newsk
);
1147 newinet
->inet_daddr
= newinet
->inet_saddr
= LOOPBACK4_IPV6
;
1148 newinet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
1150 #ifdef CONFIG_TCP_MD5SIG
1151 /* Copy over the MD5 key from the original socket */
1152 key
= tcp_v6_md5_do_lookup(sk
, &newsk
->sk_v6_daddr
);
1154 /* We're using one, so create a matching key
1155 * on the newsk structure. If we fail to get
1156 * memory, then we end up not copying the key
1159 tcp_md5_do_add(newsk
, (union tcp_md5_addr
*)&newsk
->sk_v6_daddr
,
1160 AF_INET6
, key
->key
, key
->keylen
,
1161 sk_gfp_mask(sk
, GFP_ATOMIC
));
1165 if (__inet_inherit_port(sk
, newsk
) < 0) {
1166 inet_csk_prepare_forced_close(newsk
);
1170 *own_req
= inet_ehash_nolisten(newsk
, req_to_sk(req_unhash
));
1172 tcp_move_syn(newtp
, req
);
1174 /* Clone pktoptions received with SYN, if we own the req */
1175 if (ireq
->pktopts
) {
1176 newnp
->pktoptions
= skb_clone(ireq
->pktopts
,
1177 sk_gfp_mask(sk
, GFP_ATOMIC
));
1178 consume_skb(ireq
->pktopts
);
1179 ireq
->pktopts
= NULL
;
1180 if (newnp
->pktoptions
)
1181 skb_set_owner_r(newnp
->pktoptions
, newsk
);
1188 __NET_INC_STATS(sock_net(sk
), LINUX_MIB_LISTENOVERFLOWS
);
1196 /* The socket must have it's spinlock held when we get
1197 * here, unless it is a TCP_LISTEN socket.
1199 * We have a potential double-lock case here, so even when
1200 * doing backlog processing we use the BH locking scheme.
1201 * This is because we cannot sleep with the original spinlock
1204 static int tcp_v6_do_rcv(struct sock
*sk
, struct sk_buff
*skb
)
1206 struct ipv6_pinfo
*np
= inet6_sk(sk
);
1207 struct tcp_sock
*tp
;
1208 struct sk_buff
*opt_skb
= NULL
;
1210 /* Imagine: socket is IPv6. IPv4 packet arrives,
1211 goes to IPv4 receive handler and backlogged.
1212 From backlog it always goes here. Kerboom...
1213 Fortunately, tcp_rcv_established and rcv_established
1214 handle them correctly, but it is not case with
1215 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK
1218 if (skb
->protocol
== htons(ETH_P_IP
))
1219 return tcp_v4_do_rcv(sk
, skb
);
1221 if (sk_filter(sk
, skb
))
1225 * socket locking is here for SMP purposes as backlog rcv
1226 * is currently called with bh processing disabled.
1229 /* Do Stevens' IPV6_PKTOPTIONS.
1231 Yes, guys, it is the only place in our code, where we
1232 may make it not affecting IPv4.
1233 The rest of code is protocol independent,
1234 and I do not like idea to uglify IPv4.
1236 Actually, all the idea behind IPV6_PKTOPTIONS
1237 looks not very well thought. For now we latch
1238 options, received in the last packet, enqueued
1239 by tcp. Feel free to propose better solution.
1243 opt_skb
= skb_clone(skb
, sk_gfp_mask(sk
, GFP_ATOMIC
));
1245 if (sk
->sk_state
== TCP_ESTABLISHED
) { /* Fast path */
1246 struct dst_entry
*dst
= sk
->sk_rx_dst
;
1248 sock_rps_save_rxhash(sk
, skb
);
1249 sk_mark_napi_id(sk
, skb
);
1251 if (inet_sk(sk
)->rx_dst_ifindex
!= skb
->skb_iif
||
1252 dst
->ops
->check(dst
, np
->rx_dst_cookie
) == NULL
) {
1254 sk
->sk_rx_dst
= NULL
;
1258 tcp_rcv_established(sk
, skb
, tcp_hdr(skb
), skb
->len
);
1260 goto ipv6_pktoptions
;
1264 if (tcp_checksum_complete(skb
))
1267 if (sk
->sk_state
== TCP_LISTEN
) {
1268 struct sock
*nsk
= tcp_v6_cookie_check(sk
, skb
);
1274 sock_rps_save_rxhash(nsk
, skb
);
1275 sk_mark_napi_id(nsk
, skb
);
1276 if (tcp_child_process(sk
, nsk
, skb
))
1279 __kfree_skb(opt_skb
);
1283 sock_rps_save_rxhash(sk
, skb
);
1285 if (tcp_rcv_state_process(sk
, skb
))
1288 goto ipv6_pktoptions
;
1292 tcp_v6_send_reset(sk
, skb
);
1295 __kfree_skb(opt_skb
);
1299 TCP_INC_STATS(sock_net(sk
), TCP_MIB_CSUMERRORS
);
1300 TCP_INC_STATS(sock_net(sk
), TCP_MIB_INERRS
);
1305 /* Do you ask, what is it?
1307 1. skb was enqueued by tcp.
1308 2. skb is added to tail of read queue, rather than out of order.
1309 3. socket is not in passive state.
1310 4. Finally, it really contains options, which user wants to receive.
1313 if (TCP_SKB_CB(opt_skb
)->end_seq
== tp
->rcv_nxt
&&
1314 !((1 << sk
->sk_state
) & (TCPF_CLOSE
| TCPF_LISTEN
))) {
1315 if (np
->rxopt
.bits
.rxinfo
|| np
->rxopt
.bits
.rxoinfo
)
1316 np
->mcast_oif
= tcp_v6_iif(opt_skb
);
1317 if (np
->rxopt
.bits
.rxhlim
|| np
->rxopt
.bits
.rxohlim
)
1318 np
->mcast_hops
= ipv6_hdr(opt_skb
)->hop_limit
;
1319 if (np
->rxopt
.bits
.rxflow
|| np
->rxopt
.bits
.rxtclass
)
1320 np
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(opt_skb
));
1322 np
->flow_label
= ip6_flowlabel(ipv6_hdr(opt_skb
));
1323 if (ipv6_opt_accepted(sk
, opt_skb
, &TCP_SKB_CB(opt_skb
)->header
.h6
)) {
1324 skb_set_owner_r(opt_skb
, sk
);
1325 opt_skb
= xchg(&np
->pktoptions
, opt_skb
);
1327 __kfree_skb(opt_skb
);
1328 opt_skb
= xchg(&np
->pktoptions
, NULL
);
1336 static void tcp_v6_fill_cb(struct sk_buff
*skb
, const struct ipv6hdr
*hdr
,
1337 const struct tcphdr
*th
)
1339 /* This is tricky: we move IP6CB at its correct location into
1340 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because
1341 * _decode_session6() uses IP6CB().
1342 * barrier() makes sure compiler won't play aliasing games.
1344 memmove(&TCP_SKB_CB(skb
)->header
.h6
, IP6CB(skb
),
1345 sizeof(struct inet6_skb_parm
));
1348 TCP_SKB_CB(skb
)->seq
= ntohl(th
->seq
);
1349 TCP_SKB_CB(skb
)->end_seq
= (TCP_SKB_CB(skb
)->seq
+ th
->syn
+ th
->fin
+
1350 skb
->len
- th
->doff
*4);
1351 TCP_SKB_CB(skb
)->ack_seq
= ntohl(th
->ack_seq
);
1352 TCP_SKB_CB(skb
)->tcp_flags
= tcp_flag_byte(th
);
1353 TCP_SKB_CB(skb
)->tcp_tw_isn
= 0;
1354 TCP_SKB_CB(skb
)->ip_dsfield
= ipv6_get_dsfield(hdr
);
1355 TCP_SKB_CB(skb
)->sacked
= 0;
1358 static void tcp_v6_restore_cb(struct sk_buff
*skb
)
1360 /* We need to move header back to the beginning if xfrm6_policy_check()
1361 * and tcp_v6_fill_cb() are going to be called again.
1363 memmove(IP6CB(skb
), &TCP_SKB_CB(skb
)->header
.h6
,
1364 sizeof(struct inet6_skb_parm
));
1367 static int tcp_v6_rcv(struct sk_buff
*skb
)
1369 const struct tcphdr
*th
;
1370 const struct ipv6hdr
*hdr
;
1374 struct net
*net
= dev_net(skb
->dev
);
1376 if (skb
->pkt_type
!= PACKET_HOST
)
1380 * Count it even if it's bad.
1382 __TCP_INC_STATS(net
, TCP_MIB_INSEGS
);
1384 if (!pskb_may_pull(skb
, sizeof(struct tcphdr
)))
1387 th
= (const struct tcphdr
*)skb
->data
;
1389 if (unlikely(th
->doff
< sizeof(struct tcphdr
)/4))
1391 if (!pskb_may_pull(skb
, th
->doff
*4))
1394 if (skb_checksum_init(skb
, IPPROTO_TCP
, ip6_compute_pseudo
))
1397 th
= (const struct tcphdr
*)skb
->data
;
1398 hdr
= ipv6_hdr(skb
);
1401 sk
= __inet6_lookup_skb(&tcp_hashinfo
, skb
, __tcp_hdrlen(th
),
1402 th
->source
, th
->dest
, inet6_iif(skb
),
1408 if (sk
->sk_state
== TCP_TIME_WAIT
)
1411 if (sk
->sk_state
== TCP_NEW_SYN_RECV
) {
1412 struct request_sock
*req
= inet_reqsk(sk
);
1415 sk
= req
->rsk_listener
;
1416 tcp_v6_fill_cb(skb
, hdr
, th
);
1417 if (tcp_v6_inbound_md5_hash(sk
, skb
)) {
1421 if (unlikely(sk
->sk_state
!= TCP_LISTEN
)) {
1422 inet_csk_reqsk_queue_drop_and_put(sk
, req
);
1427 nsk
= tcp_check_req(sk
, skb
, req
, false);
1430 goto discard_and_relse
;
1434 tcp_v6_restore_cb(skb
);
1435 } else if (tcp_child_process(sk
, nsk
, skb
)) {
1436 tcp_v6_send_reset(nsk
, skb
);
1437 goto discard_and_relse
;
1443 if (hdr
->hop_limit
< inet6_sk(sk
)->min_hopcount
) {
1444 __NET_INC_STATS(net
, LINUX_MIB_TCPMINTTLDROP
);
1445 goto discard_and_relse
;
1448 if (!xfrm6_policy_check(sk
, XFRM_POLICY_IN
, skb
))
1449 goto discard_and_relse
;
1451 tcp_v6_fill_cb(skb
, hdr
, th
);
1453 if (tcp_v6_inbound_md5_hash(sk
, skb
))
1454 goto discard_and_relse
;
1456 if (sk_filter(sk
, skb
))
1457 goto discard_and_relse
;
1461 if (sk
->sk_state
== TCP_LISTEN
) {
1462 ret
= tcp_v6_do_rcv(sk
, skb
);
1463 goto put_and_return
;
1466 sk_incoming_cpu_update(sk
);
1468 bh_lock_sock_nested(sk
);
1469 tcp_segs_in(tcp_sk(sk
), skb
);
1471 if (!sock_owned_by_user(sk
)) {
1472 if (!tcp_prequeue(sk
, skb
))
1473 ret
= tcp_v6_do_rcv(sk
, skb
);
1474 } else if (unlikely(sk_add_backlog(sk
, skb
,
1475 sk
->sk_rcvbuf
+ sk
->sk_sndbuf
))) {
1477 __NET_INC_STATS(net
, LINUX_MIB_TCPBACKLOGDROP
);
1478 goto discard_and_relse
;
1485 return ret
? -1 : 0;
1488 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
1491 tcp_v6_fill_cb(skb
, hdr
, th
);
1493 if (tcp_checksum_complete(skb
)) {
1495 __TCP_INC_STATS(net
, TCP_MIB_CSUMERRORS
);
1497 __TCP_INC_STATS(net
, TCP_MIB_INERRS
);
1499 tcp_v6_send_reset(NULL
, skb
);
1507 sk_drops_add(sk
, skb
);
1513 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
)) {
1514 inet_twsk_put(inet_twsk(sk
));
1518 tcp_v6_fill_cb(skb
, hdr
, th
);
1520 if (tcp_checksum_complete(skb
)) {
1521 inet_twsk_put(inet_twsk(sk
));
1525 switch (tcp_timewait_state_process(inet_twsk(sk
), skb
, th
)) {
1530 sk2
= inet6_lookup_listener(dev_net(skb
->dev
), &tcp_hashinfo
,
1531 skb
, __tcp_hdrlen(th
),
1532 &ipv6_hdr(skb
)->saddr
, th
->source
,
1533 &ipv6_hdr(skb
)->daddr
,
1534 ntohs(th
->dest
), tcp_v6_iif(skb
));
1536 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
1537 inet_twsk_deschedule_put(tw
);
1539 tcp_v6_restore_cb(skb
);
1543 /* Fall through to ACK */
1546 tcp_v6_timewait_ack(sk
, skb
);
1549 tcp_v6_restore_cb(skb
);
1550 tcp_v6_send_reset(sk
, skb
);
1551 inet_twsk_deschedule_put(inet_twsk(sk
));
1553 case TCP_TW_SUCCESS
:
1559 static void tcp_v6_early_demux(struct sk_buff
*skb
)
1561 const struct ipv6hdr
*hdr
;
1562 const struct tcphdr
*th
;
1565 if (skb
->pkt_type
!= PACKET_HOST
)
1568 if (!pskb_may_pull(skb
, skb_transport_offset(skb
) + sizeof(struct tcphdr
)))
1571 hdr
= ipv6_hdr(skb
);
1574 if (th
->doff
< sizeof(struct tcphdr
) / 4)
1577 /* Note : We use inet6_iif() here, not tcp_v6_iif() */
1578 sk
= __inet6_lookup_established(dev_net(skb
->dev
), &tcp_hashinfo
,
1579 &hdr
->saddr
, th
->source
,
1580 &hdr
->daddr
, ntohs(th
->dest
),
1584 skb
->destructor
= sock_edemux
;
1585 if (sk_fullsock(sk
)) {
1586 struct dst_entry
*dst
= READ_ONCE(sk
->sk_rx_dst
);
1589 dst
= dst_check(dst
, inet6_sk(sk
)->rx_dst_cookie
);
1591 inet_sk(sk
)->rx_dst_ifindex
== skb
->skb_iif
)
1592 skb_dst_set_noref(skb
, dst
);
1597 static struct timewait_sock_ops tcp6_timewait_sock_ops
= {
1598 .twsk_obj_size
= sizeof(struct tcp6_timewait_sock
),
1599 .twsk_unique
= tcp_twsk_unique
,
1600 .twsk_destructor
= tcp_twsk_destructor
,
1603 static const struct inet_connection_sock_af_ops ipv6_specific
= {
1604 .queue_xmit
= inet6_csk_xmit
,
1605 .send_check
= tcp_v6_send_check
,
1606 .rebuild_header
= inet6_sk_rebuild_header
,
1607 .sk_rx_dst_set
= inet6_sk_rx_dst_set
,
1608 .conn_request
= tcp_v6_conn_request
,
1609 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1610 .net_header_len
= sizeof(struct ipv6hdr
),
1611 .net_frag_header_len
= sizeof(struct frag_hdr
),
1612 .setsockopt
= ipv6_setsockopt
,
1613 .getsockopt
= ipv6_getsockopt
,
1614 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1615 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1616 .bind_conflict
= inet6_csk_bind_conflict
,
1617 #ifdef CONFIG_COMPAT
1618 .compat_setsockopt
= compat_ipv6_setsockopt
,
1619 .compat_getsockopt
= compat_ipv6_getsockopt
,
1621 .mtu_reduced
= tcp_v6_mtu_reduced
,
1624 #ifdef CONFIG_TCP_MD5SIG
1625 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific
= {
1626 .md5_lookup
= tcp_v6_md5_lookup
,
1627 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
1628 .md5_parse
= tcp_v6_parse_md5_keys
,
1633 * TCP over IPv4 via INET6 API
1635 static const struct inet_connection_sock_af_ops ipv6_mapped
= {
1636 .queue_xmit
= ip_queue_xmit
,
1637 .send_check
= tcp_v4_send_check
,
1638 .rebuild_header
= inet_sk_rebuild_header
,
1639 .sk_rx_dst_set
= inet_sk_rx_dst_set
,
1640 .conn_request
= tcp_v6_conn_request
,
1641 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1642 .net_header_len
= sizeof(struct iphdr
),
1643 .setsockopt
= ipv6_setsockopt
,
1644 .getsockopt
= ipv6_getsockopt
,
1645 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1646 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1647 .bind_conflict
= inet6_csk_bind_conflict
,
1648 #ifdef CONFIG_COMPAT
1649 .compat_setsockopt
= compat_ipv6_setsockopt
,
1650 .compat_getsockopt
= compat_ipv6_getsockopt
,
1652 .mtu_reduced
= tcp_v4_mtu_reduced
,
1655 #ifdef CONFIG_TCP_MD5SIG
1656 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific
= {
1657 .md5_lookup
= tcp_v4_md5_lookup
,
1658 .calc_md5_hash
= tcp_v4_md5_hash_skb
,
1659 .md5_parse
= tcp_v6_parse_md5_keys
,
1663 /* NOTE: A lot of things set to zero explicitly by call to
1664 * sk_alloc() so need not be done here.
1666 static int tcp_v6_init_sock(struct sock
*sk
)
1668 struct inet_connection_sock
*icsk
= inet_csk(sk
);
1672 icsk
->icsk_af_ops
= &ipv6_specific
;
1674 #ifdef CONFIG_TCP_MD5SIG
1675 tcp_sk(sk
)->af_specific
= &tcp_sock_ipv6_specific
;
1681 static void tcp_v6_destroy_sock(struct sock
*sk
)
1683 tcp_v4_destroy_sock(sk
);
1684 inet6_destroy_sock(sk
);
1687 #ifdef CONFIG_PROC_FS
1688 /* Proc filesystem TCPv6 sock list dumping. */
1689 static void get_openreq6(struct seq_file
*seq
,
1690 const struct request_sock
*req
, int i
)
1692 long ttd
= req
->rsk_timer
.expires
- jiffies
;
1693 const struct in6_addr
*src
= &inet_rsk(req
)->ir_v6_loc_addr
;
1694 const struct in6_addr
*dest
= &inet_rsk(req
)->ir_v6_rmt_addr
;
1700 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1701 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n",
1703 src
->s6_addr32
[0], src
->s6_addr32
[1],
1704 src
->s6_addr32
[2], src
->s6_addr32
[3],
1705 inet_rsk(req
)->ir_num
,
1706 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1707 dest
->s6_addr32
[2], dest
->s6_addr32
[3],
1708 ntohs(inet_rsk(req
)->ir_rmt_port
),
1710 0, 0, /* could print option size, but that is af dependent. */
1711 1, /* timers active (only the expire timer) */
1712 jiffies_to_clock_t(ttd
),
1714 from_kuid_munged(seq_user_ns(seq
),
1715 sock_i_uid(req
->rsk_listener
)),
1716 0, /* non standard timer */
1717 0, /* open_requests have no inode */
1721 static void get_tcp6_sock(struct seq_file
*seq
, struct sock
*sp
, int i
)
1723 const struct in6_addr
*dest
, *src
;
1726 unsigned long timer_expires
;
1727 const struct inet_sock
*inet
= inet_sk(sp
);
1728 const struct tcp_sock
*tp
= tcp_sk(sp
);
1729 const struct inet_connection_sock
*icsk
= inet_csk(sp
);
1730 const struct fastopen_queue
*fastopenq
= &icsk
->icsk_accept_queue
.fastopenq
;
1734 dest
= &sp
->sk_v6_daddr
;
1735 src
= &sp
->sk_v6_rcv_saddr
;
1736 destp
= ntohs(inet
->inet_dport
);
1737 srcp
= ntohs(inet
->inet_sport
);
1739 if (icsk
->icsk_pending
== ICSK_TIME_RETRANS
||
1740 icsk
->icsk_pending
== ICSK_TIME_EARLY_RETRANS
||
1741 icsk
->icsk_pending
== ICSK_TIME_LOSS_PROBE
) {
1743 timer_expires
= icsk
->icsk_timeout
;
1744 } else if (icsk
->icsk_pending
== ICSK_TIME_PROBE0
) {
1746 timer_expires
= icsk
->icsk_timeout
;
1747 } else if (timer_pending(&sp
->sk_timer
)) {
1749 timer_expires
= sp
->sk_timer
.expires
;
1752 timer_expires
= jiffies
;
1755 state
= sk_state_load(sp
);
1756 if (state
== TCP_LISTEN
)
1757 rx_queue
= sp
->sk_ack_backlog
;
1759 /* Because we don't lock the socket,
1760 * we might find a transient negative value.
1762 rx_queue
= max_t(int, tp
->rcv_nxt
- tp
->copied_seq
, 0);
1765 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1766 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n",
1768 src
->s6_addr32
[0], src
->s6_addr32
[1],
1769 src
->s6_addr32
[2], src
->s6_addr32
[3], srcp
,
1770 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1771 dest
->s6_addr32
[2], dest
->s6_addr32
[3], destp
,
1773 tp
->write_seq
- tp
->snd_una
,
1776 jiffies_delta_to_clock_t(timer_expires
- jiffies
),
1777 icsk
->icsk_retransmits
,
1778 from_kuid_munged(seq_user_ns(seq
), sock_i_uid(sp
)),
1779 icsk
->icsk_probes_out
,
1781 atomic_read(&sp
->sk_refcnt
), sp
,
1782 jiffies_to_clock_t(icsk
->icsk_rto
),
1783 jiffies_to_clock_t(icsk
->icsk_ack
.ato
),
1784 (icsk
->icsk_ack
.quick
<< 1) | icsk
->icsk_ack
.pingpong
,
1786 state
== TCP_LISTEN
?
1787 fastopenq
->max_qlen
:
1788 (tcp_in_initial_slowstart(tp
) ? -1 : tp
->snd_ssthresh
)
1792 static void get_timewait6_sock(struct seq_file
*seq
,
1793 struct inet_timewait_sock
*tw
, int i
)
1795 long delta
= tw
->tw_timer
.expires
- jiffies
;
1796 const struct in6_addr
*dest
, *src
;
1799 dest
= &tw
->tw_v6_daddr
;
1800 src
= &tw
->tw_v6_rcv_saddr
;
1801 destp
= ntohs(tw
->tw_dport
);
1802 srcp
= ntohs(tw
->tw_sport
);
1805 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1806 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
1808 src
->s6_addr32
[0], src
->s6_addr32
[1],
1809 src
->s6_addr32
[2], src
->s6_addr32
[3], srcp
,
1810 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1811 dest
->s6_addr32
[2], dest
->s6_addr32
[3], destp
,
1812 tw
->tw_substate
, 0, 0,
1813 3, jiffies_delta_to_clock_t(delta
), 0, 0, 0, 0,
1814 atomic_read(&tw
->tw_refcnt
), tw
);
1817 static int tcp6_seq_show(struct seq_file
*seq
, void *v
)
1819 struct tcp_iter_state
*st
;
1820 struct sock
*sk
= v
;
1822 if (v
== SEQ_START_TOKEN
) {
1827 "st tx_queue rx_queue tr tm->when retrnsmt"
1828 " uid timeout inode\n");
1833 if (sk
->sk_state
== TCP_TIME_WAIT
)
1834 get_timewait6_sock(seq
, v
, st
->num
);
1835 else if (sk
->sk_state
== TCP_NEW_SYN_RECV
)
1836 get_openreq6(seq
, v
, st
->num
);
1838 get_tcp6_sock(seq
, v
, st
->num
);
1843 static const struct file_operations tcp6_afinfo_seq_fops
= {
1844 .owner
= THIS_MODULE
,
1845 .open
= tcp_seq_open
,
1847 .llseek
= seq_lseek
,
1848 .release
= seq_release_net
1851 static struct tcp_seq_afinfo tcp6_seq_afinfo
= {
1854 .seq_fops
= &tcp6_afinfo_seq_fops
,
1856 .show
= tcp6_seq_show
,
1860 int __net_init
tcp6_proc_init(struct net
*net
)
1862 return tcp_proc_register(net
, &tcp6_seq_afinfo
);
1865 void tcp6_proc_exit(struct net
*net
)
1867 tcp_proc_unregister(net
, &tcp6_seq_afinfo
);
1871 static void tcp_v6_clear_sk(struct sock
*sk
, int size
)
1873 struct inet_sock
*inet
= inet_sk(sk
);
1875 /* we do not want to clear pinet6 field, because of RCU lookups */
1876 sk_prot_clear_nulls(sk
, offsetof(struct inet_sock
, pinet6
));
1878 size
-= offsetof(struct inet_sock
, pinet6
) + sizeof(inet
->pinet6
);
1879 memset(&inet
->pinet6
+ 1, 0, size
);
1882 struct proto tcpv6_prot
= {
1884 .owner
= THIS_MODULE
,
1886 .connect
= tcp_v6_connect
,
1887 .disconnect
= tcp_disconnect
,
1888 .accept
= inet_csk_accept
,
1890 .init
= tcp_v6_init_sock
,
1891 .destroy
= tcp_v6_destroy_sock
,
1892 .shutdown
= tcp_shutdown
,
1893 .setsockopt
= tcp_setsockopt
,
1894 .getsockopt
= tcp_getsockopt
,
1895 .recvmsg
= tcp_recvmsg
,
1896 .sendmsg
= tcp_sendmsg
,
1897 .sendpage
= tcp_sendpage
,
1898 .backlog_rcv
= tcp_v6_do_rcv
,
1899 .release_cb
= tcp_release_cb
,
1901 .unhash
= inet_unhash
,
1902 .get_port
= inet_csk_get_port
,
1903 .enter_memory_pressure
= tcp_enter_memory_pressure
,
1904 .stream_memory_free
= tcp_stream_memory_free
,
1905 .sockets_allocated
= &tcp_sockets_allocated
,
1906 .memory_allocated
= &tcp_memory_allocated
,
1907 .memory_pressure
= &tcp_memory_pressure
,
1908 .orphan_count
= &tcp_orphan_count
,
1909 .sysctl_mem
= sysctl_tcp_mem
,
1910 .sysctl_wmem
= sysctl_tcp_wmem
,
1911 .sysctl_rmem
= sysctl_tcp_rmem
,
1912 .max_header
= MAX_TCP_HEADER
,
1913 .obj_size
= sizeof(struct tcp6_sock
),
1914 .slab_flags
= SLAB_DESTROY_BY_RCU
,
1915 .twsk_prot
= &tcp6_timewait_sock_ops
,
1916 .rsk_prot
= &tcp6_request_sock_ops
,
1917 .h
.hashinfo
= &tcp_hashinfo
,
1918 .no_autobind
= true,
1919 #ifdef CONFIG_COMPAT
1920 .compat_setsockopt
= compat_tcp_setsockopt
,
1921 .compat_getsockopt
= compat_tcp_getsockopt
,
1923 .clear_sk
= tcp_v6_clear_sk
,
1924 .diag_destroy
= tcp_abort
,
1927 static const struct inet6_protocol tcpv6_protocol
= {
1928 .early_demux
= tcp_v6_early_demux
,
1929 .handler
= tcp_v6_rcv
,
1930 .err_handler
= tcp_v6_err
,
1931 .flags
= INET6_PROTO_NOPOLICY
|INET6_PROTO_FINAL
,
1934 static struct inet_protosw tcpv6_protosw
= {
1935 .type
= SOCK_STREAM
,
1936 .protocol
= IPPROTO_TCP
,
1937 .prot
= &tcpv6_prot
,
1938 .ops
= &inet6_stream_ops
,
1939 .flags
= INET_PROTOSW_PERMANENT
|
1943 static int __net_init
tcpv6_net_init(struct net
*net
)
1945 return inet_ctl_sock_create(&net
->ipv6
.tcp_sk
, PF_INET6
,
1946 SOCK_RAW
, IPPROTO_TCP
, net
);
1949 static void __net_exit
tcpv6_net_exit(struct net
*net
)
1951 inet_ctl_sock_destroy(net
->ipv6
.tcp_sk
);
1954 static void __net_exit
tcpv6_net_exit_batch(struct list_head
*net_exit_list
)
1956 inet_twsk_purge(&tcp_hashinfo
, &tcp_death_row
, AF_INET6
);
1959 static struct pernet_operations tcpv6_net_ops
= {
1960 .init
= tcpv6_net_init
,
1961 .exit
= tcpv6_net_exit
,
1962 .exit_batch
= tcpv6_net_exit_batch
,
1965 int __init
tcpv6_init(void)
1969 ret
= inet6_add_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
1973 /* register inet6 protocol */
1974 ret
= inet6_register_protosw(&tcpv6_protosw
);
1976 goto out_tcpv6_protocol
;
1978 ret
= register_pernet_subsys(&tcpv6_net_ops
);
1980 goto out_tcpv6_protosw
;
1985 inet6_unregister_protosw(&tcpv6_protosw
);
1987 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
1991 void tcpv6_exit(void)
1993 unregister_pernet_subsys(&tcpv6_net_ops
);
1994 inet6_unregister_protosw(&tcpv6_protosw
);
1995 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);