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
, sock_owned_by_user(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_BH(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_BH(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_BH(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_BH(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
,
444 struct inet_request_sock
*ireq
= inet_rsk(req
);
445 struct ipv6_pinfo
*np
= inet6_sk(sk
);
446 struct flowi6
*fl6
= &fl
->u
.ip6
;
450 /* First, grab a route. */
451 if (!dst
&& (dst
= inet6_csk_route_req(sk
, fl6
, req
,
452 IPPROTO_TCP
)) == NULL
)
455 skb
= tcp_make_synack(sk
, dst
, req
, foc
, attach_req
);
458 __tcp_v6_send_check(skb
, &ireq
->ir_v6_loc_addr
,
459 &ireq
->ir_v6_rmt_addr
);
461 fl6
->daddr
= ireq
->ir_v6_rmt_addr
;
462 if (np
->repflow
&& ireq
->pktopts
)
463 fl6
->flowlabel
= ip6_flowlabel(ipv6_hdr(ireq
->pktopts
));
466 err
= ip6_xmit(sk
, skb
, fl6
, rcu_dereference(np
->opt
),
469 err
= net_xmit_eval(err
);
477 static void tcp_v6_reqsk_destructor(struct request_sock
*req
)
479 kfree_skb(inet_rsk(req
)->pktopts
);
482 #ifdef CONFIG_TCP_MD5SIG
483 static struct tcp_md5sig_key
*tcp_v6_md5_do_lookup(const struct sock
*sk
,
484 const struct in6_addr
*addr
)
486 return tcp_md5_do_lookup(sk
, (union tcp_md5_addr
*)addr
, AF_INET6
);
489 static struct tcp_md5sig_key
*tcp_v6_md5_lookup(const struct sock
*sk
,
490 const struct sock
*addr_sk
)
492 return tcp_v6_md5_do_lookup(sk
, &addr_sk
->sk_v6_daddr
);
495 static int tcp_v6_parse_md5_keys(struct sock
*sk
, char __user
*optval
,
498 struct tcp_md5sig cmd
;
499 struct sockaddr_in6
*sin6
= (struct sockaddr_in6
*)&cmd
.tcpm_addr
;
501 if (optlen
< sizeof(cmd
))
504 if (copy_from_user(&cmd
, optval
, sizeof(cmd
)))
507 if (sin6
->sin6_family
!= AF_INET6
)
510 if (!cmd
.tcpm_keylen
) {
511 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
512 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
514 return tcp_md5_do_del(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
518 if (cmd
.tcpm_keylen
> TCP_MD5SIG_MAXKEYLEN
)
521 if (ipv6_addr_v4mapped(&sin6
->sin6_addr
))
522 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
.s6_addr32
[3],
523 AF_INET
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
525 return tcp_md5_do_add(sk
, (union tcp_md5_addr
*)&sin6
->sin6_addr
,
526 AF_INET6
, cmd
.tcpm_key
, cmd
.tcpm_keylen
, GFP_KERNEL
);
529 static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool
*hp
,
530 const struct in6_addr
*daddr
,
531 const struct in6_addr
*saddr
, int nbytes
)
533 struct tcp6_pseudohdr
*bp
;
534 struct scatterlist sg
;
536 bp
= &hp
->md5_blk
.ip6
;
537 /* 1. TCP pseudo-header (RFC2460) */
540 bp
->protocol
= cpu_to_be32(IPPROTO_TCP
);
541 bp
->len
= cpu_to_be32(nbytes
);
543 sg_init_one(&sg
, bp
, sizeof(*bp
));
544 ahash_request_set_crypt(hp
->md5_req
, &sg
, NULL
, sizeof(*bp
));
545 return crypto_ahash_update(hp
->md5_req
);
548 static int tcp_v6_md5_hash_hdr(char *md5_hash
, struct tcp_md5sig_key
*key
,
549 const struct in6_addr
*daddr
, struct in6_addr
*saddr
,
550 const struct tcphdr
*th
)
552 struct tcp_md5sig_pool
*hp
;
553 struct ahash_request
*req
;
555 hp
= tcp_get_md5sig_pool();
557 goto clear_hash_noput
;
560 if (crypto_ahash_init(req
))
562 if (tcp_v6_md5_hash_pseudoheader(hp
, daddr
, saddr
, th
->doff
<< 2))
564 if (tcp_md5_hash_header(hp
, th
))
566 if (tcp_md5_hash_key(hp
, key
))
568 ahash_request_set_crypt(req
, NULL
, md5_hash
, 0);
569 if (crypto_ahash_final(req
))
572 tcp_put_md5sig_pool();
576 tcp_put_md5sig_pool();
578 memset(md5_hash
, 0, 16);
582 static int tcp_v6_md5_hash_skb(char *md5_hash
,
583 const struct tcp_md5sig_key
*key
,
584 const struct sock
*sk
,
585 const struct sk_buff
*skb
)
587 const struct in6_addr
*saddr
, *daddr
;
588 struct tcp_md5sig_pool
*hp
;
589 struct ahash_request
*req
;
590 const struct tcphdr
*th
= tcp_hdr(skb
);
592 if (sk
) { /* valid for establish/request sockets */
593 saddr
= &sk
->sk_v6_rcv_saddr
;
594 daddr
= &sk
->sk_v6_daddr
;
596 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
597 saddr
= &ip6h
->saddr
;
598 daddr
= &ip6h
->daddr
;
601 hp
= tcp_get_md5sig_pool();
603 goto clear_hash_noput
;
606 if (crypto_ahash_init(req
))
609 if (tcp_v6_md5_hash_pseudoheader(hp
, daddr
, saddr
, skb
->len
))
611 if (tcp_md5_hash_header(hp
, th
))
613 if (tcp_md5_hash_skb_data(hp
, skb
, th
->doff
<< 2))
615 if (tcp_md5_hash_key(hp
, key
))
617 ahash_request_set_crypt(req
, NULL
, md5_hash
, 0);
618 if (crypto_ahash_final(req
))
621 tcp_put_md5sig_pool();
625 tcp_put_md5sig_pool();
627 memset(md5_hash
, 0, 16);
633 static bool tcp_v6_inbound_md5_hash(const struct sock
*sk
,
634 const struct sk_buff
*skb
)
636 #ifdef CONFIG_TCP_MD5SIG
637 const __u8
*hash_location
= NULL
;
638 struct tcp_md5sig_key
*hash_expected
;
639 const struct ipv6hdr
*ip6h
= ipv6_hdr(skb
);
640 const struct tcphdr
*th
= tcp_hdr(skb
);
644 hash_expected
= tcp_v6_md5_do_lookup(sk
, &ip6h
->saddr
);
645 hash_location
= tcp_parse_md5sig_option(th
);
647 /* We've parsed the options - do we have a hash? */
648 if (!hash_expected
&& !hash_location
)
651 if (hash_expected
&& !hash_location
) {
652 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_TCPMD5NOTFOUND
);
656 if (!hash_expected
&& hash_location
) {
657 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_TCPMD5UNEXPECTED
);
661 /* check the signature */
662 genhash
= tcp_v6_md5_hash_skb(newhash
,
666 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0) {
667 net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n",
668 genhash
? "failed" : "mismatch",
669 &ip6h
->saddr
, ntohs(th
->source
),
670 &ip6h
->daddr
, ntohs(th
->dest
));
677 static void tcp_v6_init_req(struct request_sock
*req
,
678 const struct sock
*sk_listener
,
681 struct inet_request_sock
*ireq
= inet_rsk(req
);
682 const struct ipv6_pinfo
*np
= inet6_sk(sk_listener
);
684 ireq
->ir_v6_rmt_addr
= ipv6_hdr(skb
)->saddr
;
685 ireq
->ir_v6_loc_addr
= ipv6_hdr(skb
)->daddr
;
687 /* So that link locals have meaning */
688 if (!sk_listener
->sk_bound_dev_if
&&
689 ipv6_addr_type(&ireq
->ir_v6_rmt_addr
) & IPV6_ADDR_LINKLOCAL
)
690 ireq
->ir_iif
= tcp_v6_iif(skb
);
692 if (!TCP_SKB_CB(skb
)->tcp_tw_isn
&&
693 (ipv6_opt_accepted(sk_listener
, skb
, &TCP_SKB_CB(skb
)->header
.h6
) ||
694 np
->rxopt
.bits
.rxinfo
||
695 np
->rxopt
.bits
.rxoinfo
|| np
->rxopt
.bits
.rxhlim
||
696 np
->rxopt
.bits
.rxohlim
|| np
->repflow
)) {
697 atomic_inc(&skb
->users
);
702 static struct dst_entry
*tcp_v6_route_req(const struct sock
*sk
,
704 const struct request_sock
*req
,
709 return inet6_csk_route_req(sk
, &fl
->u
.ip6
, req
, IPPROTO_TCP
);
712 struct request_sock_ops tcp6_request_sock_ops __read_mostly
= {
714 .obj_size
= sizeof(struct tcp6_request_sock
),
715 .rtx_syn_ack
= tcp_rtx_synack
,
716 .send_ack
= tcp_v6_reqsk_send_ack
,
717 .destructor
= tcp_v6_reqsk_destructor
,
718 .send_reset
= tcp_v6_send_reset
,
719 .syn_ack_timeout
= tcp_syn_ack_timeout
,
722 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops
= {
723 .mss_clamp
= IPV6_MIN_MTU
- sizeof(struct tcphdr
) -
724 sizeof(struct ipv6hdr
),
725 #ifdef CONFIG_TCP_MD5SIG
726 .req_md5_lookup
= tcp_v6_md5_lookup
,
727 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
729 .init_req
= tcp_v6_init_req
,
730 #ifdef CONFIG_SYN_COOKIES
731 .cookie_init_seq
= cookie_v6_init_sequence
,
733 .route_req
= tcp_v6_route_req
,
734 .init_seq
= tcp_v6_init_sequence
,
735 .send_synack
= tcp_v6_send_synack
,
738 static void tcp_v6_send_response(const struct sock
*sk
, struct sk_buff
*skb
, u32 seq
,
739 u32 ack
, u32 win
, u32 tsval
, u32 tsecr
,
740 int oif
, struct tcp_md5sig_key
*key
, int rst
,
741 u8 tclass
, u32 label
)
743 const struct tcphdr
*th
= tcp_hdr(skb
);
745 struct sk_buff
*buff
;
747 struct net
*net
= sk
? sock_net(sk
) : dev_net(skb_dst(skb
)->dev
);
748 struct sock
*ctl_sk
= net
->ipv6
.tcp_sk
;
749 unsigned int tot_len
= sizeof(struct tcphdr
);
750 struct dst_entry
*dst
;
754 tot_len
+= TCPOLEN_TSTAMP_ALIGNED
;
755 #ifdef CONFIG_TCP_MD5SIG
757 tot_len
+= TCPOLEN_MD5SIG_ALIGNED
;
760 buff
= alloc_skb(MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
,
765 skb_reserve(buff
, MAX_HEADER
+ sizeof(struct ipv6hdr
) + tot_len
);
767 t1
= (struct tcphdr
*) skb_push(buff
, tot_len
);
768 skb_reset_transport_header(buff
);
770 /* Swap the send and the receive. */
771 memset(t1
, 0, sizeof(*t1
));
772 t1
->dest
= th
->source
;
773 t1
->source
= th
->dest
;
774 t1
->doff
= tot_len
/ 4;
775 t1
->seq
= htonl(seq
);
776 t1
->ack_seq
= htonl(ack
);
777 t1
->ack
= !rst
|| !th
->ack
;
779 t1
->window
= htons(win
);
781 topt
= (__be32
*)(t1
+ 1);
784 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
785 (TCPOPT_TIMESTAMP
<< 8) | TCPOLEN_TIMESTAMP
);
786 *topt
++ = htonl(tsval
);
787 *topt
++ = htonl(tsecr
);
790 #ifdef CONFIG_TCP_MD5SIG
792 *topt
++ = htonl((TCPOPT_NOP
<< 24) | (TCPOPT_NOP
<< 16) |
793 (TCPOPT_MD5SIG
<< 8) | TCPOLEN_MD5SIG
);
794 tcp_v6_md5_hash_hdr((__u8
*)topt
, key
,
795 &ipv6_hdr(skb
)->saddr
,
796 &ipv6_hdr(skb
)->daddr
, t1
);
800 memset(&fl6
, 0, sizeof(fl6
));
801 fl6
.daddr
= ipv6_hdr(skb
)->saddr
;
802 fl6
.saddr
= ipv6_hdr(skb
)->daddr
;
803 fl6
.flowlabel
= label
;
805 buff
->ip_summed
= CHECKSUM_PARTIAL
;
808 __tcp_v6_send_check(buff
, &fl6
.saddr
, &fl6
.daddr
);
810 fl6
.flowi6_proto
= IPPROTO_TCP
;
811 if (rt6_need_strict(&fl6
.daddr
) && !oif
)
812 fl6
.flowi6_oif
= tcp_v6_iif(skb
);
814 fl6
.flowi6_oif
= oif
;
815 fl6
.flowi6_mark
= IP6_REPLY_MARK(net
, skb
->mark
);
816 fl6
.fl6_dport
= t1
->dest
;
817 fl6
.fl6_sport
= t1
->source
;
818 security_skb_classify_flow(skb
, flowi6_to_flowi(&fl6
));
820 /* Pass a socket to ip6_dst_lookup either it is for RST
821 * Underlying function will use this to retrieve the network
824 dst
= ip6_dst_lookup_flow(ctl_sk
, &fl6
, NULL
);
826 skb_dst_set(buff
, dst
);
827 ip6_xmit(ctl_sk
, buff
, &fl6
, NULL
, tclass
);
828 TCP_INC_STATS_BH(net
, TCP_MIB_OUTSEGS
);
830 TCP_INC_STATS_BH(net
, TCP_MIB_OUTRSTS
);
837 static void tcp_v6_send_reset(const struct sock
*sk
, struct sk_buff
*skb
)
839 const struct tcphdr
*th
= tcp_hdr(skb
);
840 u32 seq
= 0, ack_seq
= 0;
841 struct tcp_md5sig_key
*key
= NULL
;
842 #ifdef CONFIG_TCP_MD5SIG
843 const __u8
*hash_location
= NULL
;
844 struct ipv6hdr
*ipv6h
= ipv6_hdr(skb
);
845 unsigned char newhash
[16];
847 struct sock
*sk1
= NULL
;
854 /* If sk not NULL, it means we did a successful lookup and incoming
855 * route had to be correct. prequeue might have dropped our dst.
857 if (!sk
&& !ipv6_unicast_destination(skb
))
860 #ifdef CONFIG_TCP_MD5SIG
861 hash_location
= tcp_parse_md5sig_option(th
);
862 if (sk
&& sk_fullsock(sk
)) {
863 key
= tcp_v6_md5_do_lookup(sk
, &ipv6h
->saddr
);
864 } else if (hash_location
) {
866 * active side is lost. Try to find listening socket through
867 * source port, and then find md5 key through listening socket.
868 * we are not loose security here:
869 * Incoming packet is checked with md5 hash with finding key,
870 * no RST generated if md5 hash doesn't match.
872 sk1
= inet6_lookup_listener(dev_net(skb_dst(skb
)->dev
),
873 &tcp_hashinfo
, NULL
, 0,
875 th
->source
, &ipv6h
->daddr
,
876 ntohs(th
->source
), tcp_v6_iif(skb
));
881 key
= tcp_v6_md5_do_lookup(sk1
, &ipv6h
->saddr
);
885 genhash
= tcp_v6_md5_hash_skb(newhash
, key
, NULL
, skb
);
886 if (genhash
|| memcmp(hash_location
, newhash
, 16) != 0)
892 seq
= ntohl(th
->ack_seq
);
894 ack_seq
= ntohl(th
->seq
) + th
->syn
+ th
->fin
+ skb
->len
-
897 oif
= sk
? sk
->sk_bound_dev_if
: 0;
898 tcp_v6_send_response(sk
, skb
, seq
, ack_seq
, 0, 0, 0, oif
, key
, 1, 0, 0);
900 #ifdef CONFIG_TCP_MD5SIG
909 static void tcp_v6_send_ack(const struct sock
*sk
, struct sk_buff
*skb
, u32 seq
,
910 u32 ack
, u32 win
, u32 tsval
, u32 tsecr
, int oif
,
911 struct tcp_md5sig_key
*key
, u8 tclass
,
914 tcp_v6_send_response(sk
, skb
, seq
, ack
, win
, tsval
, tsecr
, oif
, key
, 0,
918 static void tcp_v6_timewait_ack(struct sock
*sk
, struct sk_buff
*skb
)
920 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
921 struct tcp_timewait_sock
*tcptw
= tcp_twsk(sk
);
923 tcp_v6_send_ack(sk
, skb
, tcptw
->tw_snd_nxt
, tcptw
->tw_rcv_nxt
,
924 tcptw
->tw_rcv_wnd
>> tw
->tw_rcv_wscale
,
925 tcp_time_stamp
+ tcptw
->tw_ts_offset
,
926 tcptw
->tw_ts_recent
, tw
->tw_bound_dev_if
, tcp_twsk_md5_key(tcptw
),
927 tw
->tw_tclass
, cpu_to_be32(tw
->tw_flowlabel
));
932 static void tcp_v6_reqsk_send_ack(const struct sock
*sk
, struct sk_buff
*skb
,
933 struct request_sock
*req
)
935 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV
936 * sk->sk_state == TCP_SYN_RECV -> for Fast Open.
938 tcp_v6_send_ack(sk
, skb
, (sk
->sk_state
== TCP_LISTEN
) ?
939 tcp_rsk(req
)->snt_isn
+ 1 : tcp_sk(sk
)->snd_nxt
,
940 tcp_rsk(req
)->rcv_nxt
, req
->rsk_rcv_wnd
,
941 tcp_time_stamp
, req
->ts_recent
, sk
->sk_bound_dev_if
,
942 tcp_v6_md5_do_lookup(sk
, &ipv6_hdr(skb
)->daddr
),
947 static struct sock
*tcp_v6_cookie_check(struct sock
*sk
, struct sk_buff
*skb
)
949 #ifdef CONFIG_SYN_COOKIES
950 const struct tcphdr
*th
= tcp_hdr(skb
);
953 sk
= cookie_v6_check(sk
, skb
);
958 static int tcp_v6_conn_request(struct sock
*sk
, struct sk_buff
*skb
)
960 if (skb
->protocol
== htons(ETH_P_IP
))
961 return tcp_v4_conn_request(sk
, skb
);
963 if (!ipv6_unicast_destination(skb
))
966 return tcp_conn_request(&tcp6_request_sock_ops
,
967 &tcp_request_sock_ipv6_ops
, sk
, skb
);
970 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_LISTENDROPS
);
971 return 0; /* don't send reset */
974 static struct sock
*tcp_v6_syn_recv_sock(const struct sock
*sk
, struct sk_buff
*skb
,
975 struct request_sock
*req
,
976 struct dst_entry
*dst
,
977 struct request_sock
*req_unhash
,
980 struct inet_request_sock
*ireq
;
981 struct ipv6_pinfo
*newnp
;
982 const struct ipv6_pinfo
*np
= inet6_sk(sk
);
983 struct ipv6_txoptions
*opt
;
984 struct tcp6_sock
*newtcp6sk
;
985 struct inet_sock
*newinet
;
986 struct tcp_sock
*newtp
;
988 #ifdef CONFIG_TCP_MD5SIG
989 struct tcp_md5sig_key
*key
;
993 if (skb
->protocol
== htons(ETH_P_IP
)) {
998 newsk
= tcp_v4_syn_recv_sock(sk
, skb
, req
, dst
,
999 req_unhash
, own_req
);
1004 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1005 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1007 newinet
= inet_sk(newsk
);
1008 newnp
= inet6_sk(newsk
);
1009 newtp
= tcp_sk(newsk
);
1011 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1013 newnp
->saddr
= newsk
->sk_v6_rcv_saddr
;
1015 inet_csk(newsk
)->icsk_af_ops
= &ipv6_mapped
;
1016 newsk
->sk_backlog_rcv
= tcp_v4_do_rcv
;
1017 #ifdef CONFIG_TCP_MD5SIG
1018 newtp
->af_specific
= &tcp_sock_ipv6_mapped_specific
;
1021 newnp
->ipv6_ac_list
= NULL
;
1022 newnp
->ipv6_fl_list
= NULL
;
1023 newnp
->pktoptions
= NULL
;
1025 newnp
->mcast_oif
= tcp_v6_iif(skb
);
1026 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1027 newnp
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(skb
));
1029 newnp
->flow_label
= ip6_flowlabel(ipv6_hdr(skb
));
1032 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
1033 * here, tcp_create_openreq_child now does this for us, see the comment in
1034 * that function for the gory details. -acme
1037 /* It is tricky place. Until this moment IPv4 tcp
1038 worked with IPv6 icsk.icsk_af_ops.
1041 tcp_sync_mss(newsk
, inet_csk(newsk
)->icsk_pmtu_cookie
);
1046 ireq
= inet_rsk(req
);
1048 if (sk_acceptq_is_full(sk
))
1052 dst
= inet6_csk_route_req(sk
, &fl6
, req
, IPPROTO_TCP
);
1057 newsk
= tcp_create_openreq_child(sk
, req
, skb
);
1062 * No need to charge this sock to the relevant IPv6 refcnt debug socks
1063 * count here, tcp_create_openreq_child now does this for us, see the
1064 * comment in that function for the gory details. -acme
1067 newsk
->sk_gso_type
= SKB_GSO_TCPV6
;
1068 ip6_dst_store(newsk
, dst
, NULL
, NULL
);
1069 inet6_sk_rx_dst_set(newsk
, skb
);
1071 newtcp6sk
= (struct tcp6_sock
*)newsk
;
1072 inet_sk(newsk
)->pinet6
= &newtcp6sk
->inet6
;
1074 newtp
= tcp_sk(newsk
);
1075 newinet
= inet_sk(newsk
);
1076 newnp
= inet6_sk(newsk
);
1078 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
1080 newsk
->sk_v6_daddr
= ireq
->ir_v6_rmt_addr
;
1081 newnp
->saddr
= ireq
->ir_v6_loc_addr
;
1082 newsk
->sk_v6_rcv_saddr
= ireq
->ir_v6_loc_addr
;
1083 newsk
->sk_bound_dev_if
= ireq
->ir_iif
;
1085 /* Now IPv6 options...
1087 First: no IPv4 options.
1089 newinet
->inet_opt
= NULL
;
1090 newnp
->ipv6_ac_list
= NULL
;
1091 newnp
->ipv6_fl_list
= NULL
;
1094 newnp
->rxopt
.all
= np
->rxopt
.all
;
1096 newnp
->pktoptions
= NULL
;
1098 newnp
->mcast_oif
= tcp_v6_iif(skb
);
1099 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
1100 newnp
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(skb
));
1102 newnp
->flow_label
= ip6_flowlabel(ipv6_hdr(skb
));
1104 /* Clone native IPv6 options from listening socket (if any)
1106 Yes, keeping reference count would be much more clever,
1107 but we make one more one thing there: reattach optmem
1110 opt
= rcu_dereference(np
->opt
);
1112 opt
= ipv6_dup_options(newsk
, opt
);
1113 RCU_INIT_POINTER(newnp
->opt
, opt
);
1115 inet_csk(newsk
)->icsk_ext_hdr_len
= 0;
1117 inet_csk(newsk
)->icsk_ext_hdr_len
= opt
->opt_nflen
+
1120 tcp_ca_openreq_child(newsk
, dst
);
1122 tcp_sync_mss(newsk
, dst_mtu(dst
));
1123 newtp
->advmss
= dst_metric_advmss(dst
);
1124 if (tcp_sk(sk
)->rx_opt
.user_mss
&&
1125 tcp_sk(sk
)->rx_opt
.user_mss
< newtp
->advmss
)
1126 newtp
->advmss
= tcp_sk(sk
)->rx_opt
.user_mss
;
1128 tcp_initialize_rcv_mss(newsk
);
1130 newinet
->inet_daddr
= newinet
->inet_saddr
= LOOPBACK4_IPV6
;
1131 newinet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
1133 #ifdef CONFIG_TCP_MD5SIG
1134 /* Copy over the MD5 key from the original socket */
1135 key
= tcp_v6_md5_do_lookup(sk
, &newsk
->sk_v6_daddr
);
1137 /* We're using one, so create a matching key
1138 * on the newsk structure. If we fail to get
1139 * memory, then we end up not copying the key
1142 tcp_md5_do_add(newsk
, (union tcp_md5_addr
*)&newsk
->sk_v6_daddr
,
1143 AF_INET6
, key
->key
, key
->keylen
,
1144 sk_gfp_mask(sk
, GFP_ATOMIC
));
1148 if (__inet_inherit_port(sk
, newsk
) < 0) {
1149 inet_csk_prepare_forced_close(newsk
);
1153 *own_req
= inet_ehash_nolisten(newsk
, req_to_sk(req_unhash
));
1155 tcp_move_syn(newtp
, req
);
1157 /* Clone pktoptions received with SYN, if we own the req */
1158 if (ireq
->pktopts
) {
1159 newnp
->pktoptions
= skb_clone(ireq
->pktopts
,
1160 sk_gfp_mask(sk
, GFP_ATOMIC
));
1161 consume_skb(ireq
->pktopts
);
1162 ireq
->pktopts
= NULL
;
1163 if (newnp
->pktoptions
)
1164 skb_set_owner_r(newnp
->pktoptions
, newsk
);
1171 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_LISTENOVERFLOWS
);
1175 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_LISTENDROPS
);
1179 /* The socket must have it's spinlock held when we get
1180 * here, unless it is a TCP_LISTEN socket.
1182 * We have a potential double-lock case here, so even when
1183 * doing backlog processing we use the BH locking scheme.
1184 * This is because we cannot sleep with the original spinlock
1187 static int tcp_v6_do_rcv(struct sock
*sk
, struct sk_buff
*skb
)
1189 struct ipv6_pinfo
*np
= inet6_sk(sk
);
1190 struct tcp_sock
*tp
;
1191 struct sk_buff
*opt_skb
= NULL
;
1193 /* Imagine: socket is IPv6. IPv4 packet arrives,
1194 goes to IPv4 receive handler and backlogged.
1195 From backlog it always goes here. Kerboom...
1196 Fortunately, tcp_rcv_established and rcv_established
1197 handle them correctly, but it is not case with
1198 tcp_v6_hnd_req and tcp_v6_send_reset(). --ANK
1201 if (skb
->protocol
== htons(ETH_P_IP
))
1202 return tcp_v4_do_rcv(sk
, skb
);
1204 if (sk_filter(sk
, skb
))
1208 * socket locking is here for SMP purposes as backlog rcv
1209 * is currently called with bh processing disabled.
1212 /* Do Stevens' IPV6_PKTOPTIONS.
1214 Yes, guys, it is the only place in our code, where we
1215 may make it not affecting IPv4.
1216 The rest of code is protocol independent,
1217 and I do not like idea to uglify IPv4.
1219 Actually, all the idea behind IPV6_PKTOPTIONS
1220 looks not very well thought. For now we latch
1221 options, received in the last packet, enqueued
1222 by tcp. Feel free to propose better solution.
1226 opt_skb
= skb_clone(skb
, sk_gfp_mask(sk
, GFP_ATOMIC
));
1228 if (sk
->sk_state
== TCP_ESTABLISHED
) { /* Fast path */
1229 struct dst_entry
*dst
= sk
->sk_rx_dst
;
1231 sock_rps_save_rxhash(sk
, skb
);
1232 sk_mark_napi_id(sk
, skb
);
1234 if (inet_sk(sk
)->rx_dst_ifindex
!= skb
->skb_iif
||
1235 dst
->ops
->check(dst
, np
->rx_dst_cookie
) == NULL
) {
1237 sk
->sk_rx_dst
= NULL
;
1241 tcp_rcv_established(sk
, skb
, tcp_hdr(skb
), skb
->len
);
1243 goto ipv6_pktoptions
;
1247 if (tcp_checksum_complete(skb
))
1250 if (sk
->sk_state
== TCP_LISTEN
) {
1251 struct sock
*nsk
= tcp_v6_cookie_check(sk
, skb
);
1257 sock_rps_save_rxhash(nsk
, skb
);
1258 sk_mark_napi_id(nsk
, skb
);
1259 if (tcp_child_process(sk
, nsk
, skb
))
1262 __kfree_skb(opt_skb
);
1266 sock_rps_save_rxhash(sk
, skb
);
1268 if (tcp_rcv_state_process(sk
, skb
))
1271 goto ipv6_pktoptions
;
1275 tcp_v6_send_reset(sk
, skb
);
1278 __kfree_skb(opt_skb
);
1282 TCP_INC_STATS_BH(sock_net(sk
), TCP_MIB_CSUMERRORS
);
1283 TCP_INC_STATS_BH(sock_net(sk
), TCP_MIB_INERRS
);
1288 /* Do you ask, what is it?
1290 1. skb was enqueued by tcp.
1291 2. skb is added to tail of read queue, rather than out of order.
1292 3. socket is not in passive state.
1293 4. Finally, it really contains options, which user wants to receive.
1296 if (TCP_SKB_CB(opt_skb
)->end_seq
== tp
->rcv_nxt
&&
1297 !((1 << sk
->sk_state
) & (TCPF_CLOSE
| TCPF_LISTEN
))) {
1298 if (np
->rxopt
.bits
.rxinfo
|| np
->rxopt
.bits
.rxoinfo
)
1299 np
->mcast_oif
= tcp_v6_iif(opt_skb
);
1300 if (np
->rxopt
.bits
.rxhlim
|| np
->rxopt
.bits
.rxohlim
)
1301 np
->mcast_hops
= ipv6_hdr(opt_skb
)->hop_limit
;
1302 if (np
->rxopt
.bits
.rxflow
|| np
->rxopt
.bits
.rxtclass
)
1303 np
->rcv_flowinfo
= ip6_flowinfo(ipv6_hdr(opt_skb
));
1305 np
->flow_label
= ip6_flowlabel(ipv6_hdr(opt_skb
));
1306 if (ipv6_opt_accepted(sk
, opt_skb
, &TCP_SKB_CB(opt_skb
)->header
.h6
)) {
1307 skb_set_owner_r(opt_skb
, sk
);
1308 opt_skb
= xchg(&np
->pktoptions
, opt_skb
);
1310 __kfree_skb(opt_skb
);
1311 opt_skb
= xchg(&np
->pktoptions
, NULL
);
1319 static void tcp_v6_fill_cb(struct sk_buff
*skb
, const struct ipv6hdr
*hdr
,
1320 const struct tcphdr
*th
)
1322 /* This is tricky: we move IP6CB at its correct location into
1323 * TCP_SKB_CB(). It must be done after xfrm6_policy_check(), because
1324 * _decode_session6() uses IP6CB().
1325 * barrier() makes sure compiler won't play aliasing games.
1327 memmove(&TCP_SKB_CB(skb
)->header
.h6
, IP6CB(skb
),
1328 sizeof(struct inet6_skb_parm
));
1331 TCP_SKB_CB(skb
)->seq
= ntohl(th
->seq
);
1332 TCP_SKB_CB(skb
)->end_seq
= (TCP_SKB_CB(skb
)->seq
+ th
->syn
+ th
->fin
+
1333 skb
->len
- th
->doff
*4);
1334 TCP_SKB_CB(skb
)->ack_seq
= ntohl(th
->ack_seq
);
1335 TCP_SKB_CB(skb
)->tcp_flags
= tcp_flag_byte(th
);
1336 TCP_SKB_CB(skb
)->tcp_tw_isn
= 0;
1337 TCP_SKB_CB(skb
)->ip_dsfield
= ipv6_get_dsfield(hdr
);
1338 TCP_SKB_CB(skb
)->sacked
= 0;
1341 static void tcp_v6_restore_cb(struct sk_buff
*skb
)
1343 /* We need to move header back to the beginning if xfrm6_policy_check()
1344 * and tcp_v6_fill_cb() are going to be called again.
1346 memmove(IP6CB(skb
), &TCP_SKB_CB(skb
)->header
.h6
,
1347 sizeof(struct inet6_skb_parm
));
1350 static int tcp_v6_rcv(struct sk_buff
*skb
)
1352 const struct tcphdr
*th
;
1353 const struct ipv6hdr
*hdr
;
1356 struct net
*net
= dev_net(skb
->dev
);
1358 if (skb
->pkt_type
!= PACKET_HOST
)
1362 * Count it even if it's bad.
1364 TCP_INC_STATS_BH(net
, TCP_MIB_INSEGS
);
1366 if (!pskb_may_pull(skb
, sizeof(struct tcphdr
)))
1371 if (th
->doff
< sizeof(struct tcphdr
)/4)
1373 if (!pskb_may_pull(skb
, th
->doff
*4))
1376 if (skb_checksum_init(skb
, IPPROTO_TCP
, ip6_compute_pseudo
))
1380 hdr
= ipv6_hdr(skb
);
1383 sk
= __inet6_lookup_skb(&tcp_hashinfo
, skb
, __tcp_hdrlen(th
),
1384 th
->source
, th
->dest
, inet6_iif(skb
));
1389 if (sk
->sk_state
== TCP_TIME_WAIT
)
1392 if (sk
->sk_state
== TCP_NEW_SYN_RECV
) {
1393 struct request_sock
*req
= inet_reqsk(sk
);
1396 sk
= req
->rsk_listener
;
1397 tcp_v6_fill_cb(skb
, hdr
, th
);
1398 if (tcp_v6_inbound_md5_hash(sk
, skb
)) {
1402 if (unlikely(sk
->sk_state
!= TCP_LISTEN
)) {
1403 inet_csk_reqsk_queue_drop_and_put(sk
, req
);
1407 nsk
= tcp_check_req(sk
, skb
, req
, false);
1410 goto discard_and_relse
;
1414 tcp_v6_restore_cb(skb
);
1415 } else if (tcp_child_process(sk
, nsk
, skb
)) {
1416 tcp_v6_send_reset(nsk
, skb
);
1417 goto discard_and_relse
;
1423 if (hdr
->hop_limit
< inet6_sk(sk
)->min_hopcount
) {
1424 NET_INC_STATS_BH(net
, LINUX_MIB_TCPMINTTLDROP
);
1425 goto discard_and_relse
;
1428 if (!xfrm6_policy_check(sk
, XFRM_POLICY_IN
, skb
))
1429 goto discard_and_relse
;
1431 tcp_v6_fill_cb(skb
, hdr
, th
);
1433 if (tcp_v6_inbound_md5_hash(sk
, skb
))
1434 goto discard_and_relse
;
1436 if (sk_filter(sk
, skb
))
1437 goto discard_and_relse
;
1441 if (sk
->sk_state
== TCP_LISTEN
) {
1442 ret
= tcp_v6_do_rcv(sk
, skb
);
1443 goto put_and_return
;
1446 sk_incoming_cpu_update(sk
);
1448 bh_lock_sock_nested(sk
);
1449 tcp_segs_in(tcp_sk(sk
), skb
);
1451 if (!sock_owned_by_user(sk
)) {
1452 if (!tcp_prequeue(sk
, skb
))
1453 ret
= tcp_v6_do_rcv(sk
, skb
);
1454 } else if (unlikely(sk_add_backlog(sk
, skb
,
1455 sk
->sk_rcvbuf
+ sk
->sk_sndbuf
))) {
1457 NET_INC_STATS_BH(net
, LINUX_MIB_TCPBACKLOGDROP
);
1458 goto discard_and_relse
;
1464 return ret
? -1 : 0;
1467 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
1470 tcp_v6_fill_cb(skb
, hdr
, th
);
1472 if (tcp_checksum_complete(skb
)) {
1474 TCP_INC_STATS_BH(net
, TCP_MIB_CSUMERRORS
);
1476 TCP_INC_STATS_BH(net
, TCP_MIB_INERRS
);
1478 tcp_v6_send_reset(NULL
, skb
);
1490 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
)) {
1491 inet_twsk_put(inet_twsk(sk
));
1495 tcp_v6_fill_cb(skb
, hdr
, th
);
1497 if (tcp_checksum_complete(skb
)) {
1498 inet_twsk_put(inet_twsk(sk
));
1502 switch (tcp_timewait_state_process(inet_twsk(sk
), skb
, th
)) {
1507 sk2
= inet6_lookup_listener(dev_net(skb
->dev
), &tcp_hashinfo
,
1508 skb
, __tcp_hdrlen(th
),
1509 &ipv6_hdr(skb
)->saddr
, th
->source
,
1510 &ipv6_hdr(skb
)->daddr
,
1511 ntohs(th
->dest
), tcp_v6_iif(skb
));
1513 struct inet_timewait_sock
*tw
= inet_twsk(sk
);
1514 inet_twsk_deschedule_put(tw
);
1516 tcp_v6_restore_cb(skb
);
1519 /* Fall through to ACK */
1522 tcp_v6_timewait_ack(sk
, skb
);
1525 tcp_v6_restore_cb(skb
);
1526 tcp_v6_send_reset(sk
, skb
);
1527 inet_twsk_deschedule_put(inet_twsk(sk
));
1529 case TCP_TW_SUCCESS
:
1535 static void tcp_v6_early_demux(struct sk_buff
*skb
)
1537 const struct ipv6hdr
*hdr
;
1538 const struct tcphdr
*th
;
1541 if (skb
->pkt_type
!= PACKET_HOST
)
1544 if (!pskb_may_pull(skb
, skb_transport_offset(skb
) + sizeof(struct tcphdr
)))
1547 hdr
= ipv6_hdr(skb
);
1550 if (th
->doff
< sizeof(struct tcphdr
) / 4)
1553 /* Note : We use inet6_iif() here, not tcp_v6_iif() */
1554 sk
= __inet6_lookup_established(dev_net(skb
->dev
), &tcp_hashinfo
,
1555 &hdr
->saddr
, th
->source
,
1556 &hdr
->daddr
, ntohs(th
->dest
),
1560 skb
->destructor
= sock_edemux
;
1561 if (sk_fullsock(sk
)) {
1562 struct dst_entry
*dst
= READ_ONCE(sk
->sk_rx_dst
);
1565 dst
= dst_check(dst
, inet6_sk(sk
)->rx_dst_cookie
);
1567 inet_sk(sk
)->rx_dst_ifindex
== skb
->skb_iif
)
1568 skb_dst_set_noref(skb
, dst
);
1573 static struct timewait_sock_ops tcp6_timewait_sock_ops
= {
1574 .twsk_obj_size
= sizeof(struct tcp6_timewait_sock
),
1575 .twsk_unique
= tcp_twsk_unique
,
1576 .twsk_destructor
= tcp_twsk_destructor
,
1579 static const struct inet_connection_sock_af_ops ipv6_specific
= {
1580 .queue_xmit
= inet6_csk_xmit
,
1581 .send_check
= tcp_v6_send_check
,
1582 .rebuild_header
= inet6_sk_rebuild_header
,
1583 .sk_rx_dst_set
= inet6_sk_rx_dst_set
,
1584 .conn_request
= tcp_v6_conn_request
,
1585 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1586 .net_header_len
= sizeof(struct ipv6hdr
),
1587 .net_frag_header_len
= sizeof(struct frag_hdr
),
1588 .setsockopt
= ipv6_setsockopt
,
1589 .getsockopt
= ipv6_getsockopt
,
1590 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1591 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1592 .bind_conflict
= inet6_csk_bind_conflict
,
1593 #ifdef CONFIG_COMPAT
1594 .compat_setsockopt
= compat_ipv6_setsockopt
,
1595 .compat_getsockopt
= compat_ipv6_getsockopt
,
1597 .mtu_reduced
= tcp_v6_mtu_reduced
,
1600 #ifdef CONFIG_TCP_MD5SIG
1601 static const struct tcp_sock_af_ops tcp_sock_ipv6_specific
= {
1602 .md5_lookup
= tcp_v6_md5_lookup
,
1603 .calc_md5_hash
= tcp_v6_md5_hash_skb
,
1604 .md5_parse
= tcp_v6_parse_md5_keys
,
1609 * TCP over IPv4 via INET6 API
1611 static const struct inet_connection_sock_af_ops ipv6_mapped
= {
1612 .queue_xmit
= ip_queue_xmit
,
1613 .send_check
= tcp_v4_send_check
,
1614 .rebuild_header
= inet_sk_rebuild_header
,
1615 .sk_rx_dst_set
= inet_sk_rx_dst_set
,
1616 .conn_request
= tcp_v6_conn_request
,
1617 .syn_recv_sock
= tcp_v6_syn_recv_sock
,
1618 .net_header_len
= sizeof(struct iphdr
),
1619 .setsockopt
= ipv6_setsockopt
,
1620 .getsockopt
= ipv6_getsockopt
,
1621 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1622 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1623 .bind_conflict
= inet6_csk_bind_conflict
,
1624 #ifdef CONFIG_COMPAT
1625 .compat_setsockopt
= compat_ipv6_setsockopt
,
1626 .compat_getsockopt
= compat_ipv6_getsockopt
,
1628 .mtu_reduced
= tcp_v4_mtu_reduced
,
1631 #ifdef CONFIG_TCP_MD5SIG
1632 static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific
= {
1633 .md5_lookup
= tcp_v4_md5_lookup
,
1634 .calc_md5_hash
= tcp_v4_md5_hash_skb
,
1635 .md5_parse
= tcp_v6_parse_md5_keys
,
1639 /* NOTE: A lot of things set to zero explicitly by call to
1640 * sk_alloc() so need not be done here.
1642 static int tcp_v6_init_sock(struct sock
*sk
)
1644 struct inet_connection_sock
*icsk
= inet_csk(sk
);
1648 icsk
->icsk_af_ops
= &ipv6_specific
;
1650 #ifdef CONFIG_TCP_MD5SIG
1651 tcp_sk(sk
)->af_specific
= &tcp_sock_ipv6_specific
;
1657 static void tcp_v6_destroy_sock(struct sock
*sk
)
1659 tcp_v4_destroy_sock(sk
);
1660 inet6_destroy_sock(sk
);
1663 #ifdef CONFIG_PROC_FS
1664 /* Proc filesystem TCPv6 sock list dumping. */
1665 static void get_openreq6(struct seq_file
*seq
,
1666 const struct request_sock
*req
, int i
)
1668 long ttd
= req
->rsk_timer
.expires
- jiffies
;
1669 const struct in6_addr
*src
= &inet_rsk(req
)->ir_v6_loc_addr
;
1670 const struct in6_addr
*dest
= &inet_rsk(req
)->ir_v6_rmt_addr
;
1676 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1677 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %d %d %pK\n",
1679 src
->s6_addr32
[0], src
->s6_addr32
[1],
1680 src
->s6_addr32
[2], src
->s6_addr32
[3],
1681 inet_rsk(req
)->ir_num
,
1682 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1683 dest
->s6_addr32
[2], dest
->s6_addr32
[3],
1684 ntohs(inet_rsk(req
)->ir_rmt_port
),
1686 0, 0, /* could print option size, but that is af dependent. */
1687 1, /* timers active (only the expire timer) */
1688 jiffies_to_clock_t(ttd
),
1690 from_kuid_munged(seq_user_ns(seq
),
1691 sock_i_uid(req
->rsk_listener
)),
1692 0, /* non standard timer */
1693 0, /* open_requests have no inode */
1697 static void get_tcp6_sock(struct seq_file
*seq
, struct sock
*sp
, int i
)
1699 const struct in6_addr
*dest
, *src
;
1702 unsigned long timer_expires
;
1703 const struct inet_sock
*inet
= inet_sk(sp
);
1704 const struct tcp_sock
*tp
= tcp_sk(sp
);
1705 const struct inet_connection_sock
*icsk
= inet_csk(sp
);
1706 const struct fastopen_queue
*fastopenq
= &icsk
->icsk_accept_queue
.fastopenq
;
1710 dest
= &sp
->sk_v6_daddr
;
1711 src
= &sp
->sk_v6_rcv_saddr
;
1712 destp
= ntohs(inet
->inet_dport
);
1713 srcp
= ntohs(inet
->inet_sport
);
1715 if (icsk
->icsk_pending
== ICSK_TIME_RETRANS
) {
1717 timer_expires
= icsk
->icsk_timeout
;
1718 } else if (icsk
->icsk_pending
== ICSK_TIME_PROBE0
) {
1720 timer_expires
= icsk
->icsk_timeout
;
1721 } else if (timer_pending(&sp
->sk_timer
)) {
1723 timer_expires
= sp
->sk_timer
.expires
;
1726 timer_expires
= jiffies
;
1729 state
= sk_state_load(sp
);
1730 if (state
== TCP_LISTEN
)
1731 rx_queue
= sp
->sk_ack_backlog
;
1733 /* Because we don't lock the socket,
1734 * we might find a transient negative value.
1736 rx_queue
= max_t(int, tp
->rcv_nxt
- tp
->copied_seq
, 0);
1739 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1740 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %lu %lu %u %u %d\n",
1742 src
->s6_addr32
[0], src
->s6_addr32
[1],
1743 src
->s6_addr32
[2], src
->s6_addr32
[3], srcp
,
1744 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1745 dest
->s6_addr32
[2], dest
->s6_addr32
[3], destp
,
1747 tp
->write_seq
- tp
->snd_una
,
1750 jiffies_delta_to_clock_t(timer_expires
- jiffies
),
1751 icsk
->icsk_retransmits
,
1752 from_kuid_munged(seq_user_ns(seq
), sock_i_uid(sp
)),
1753 icsk
->icsk_probes_out
,
1755 atomic_read(&sp
->sk_refcnt
), sp
,
1756 jiffies_to_clock_t(icsk
->icsk_rto
),
1757 jiffies_to_clock_t(icsk
->icsk_ack
.ato
),
1758 (icsk
->icsk_ack
.quick
<< 1) | icsk
->icsk_ack
.pingpong
,
1760 state
== TCP_LISTEN
?
1761 fastopenq
->max_qlen
:
1762 (tcp_in_initial_slowstart(tp
) ? -1 : tp
->snd_ssthresh
)
1766 static void get_timewait6_sock(struct seq_file
*seq
,
1767 struct inet_timewait_sock
*tw
, int i
)
1769 long delta
= tw
->tw_timer
.expires
- jiffies
;
1770 const struct in6_addr
*dest
, *src
;
1773 dest
= &tw
->tw_v6_daddr
;
1774 src
= &tw
->tw_v6_rcv_saddr
;
1775 destp
= ntohs(tw
->tw_dport
);
1776 srcp
= ntohs(tw
->tw_sport
);
1779 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1780 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
1782 src
->s6_addr32
[0], src
->s6_addr32
[1],
1783 src
->s6_addr32
[2], src
->s6_addr32
[3], srcp
,
1784 dest
->s6_addr32
[0], dest
->s6_addr32
[1],
1785 dest
->s6_addr32
[2], dest
->s6_addr32
[3], destp
,
1786 tw
->tw_substate
, 0, 0,
1787 3, jiffies_delta_to_clock_t(delta
), 0, 0, 0, 0,
1788 atomic_read(&tw
->tw_refcnt
), tw
);
1791 static int tcp6_seq_show(struct seq_file
*seq
, void *v
)
1793 struct tcp_iter_state
*st
;
1794 struct sock
*sk
= v
;
1796 if (v
== SEQ_START_TOKEN
) {
1801 "st tx_queue rx_queue tr tm->when retrnsmt"
1802 " uid timeout inode\n");
1807 if (sk
->sk_state
== TCP_TIME_WAIT
)
1808 get_timewait6_sock(seq
, v
, st
->num
);
1809 else if (sk
->sk_state
== TCP_NEW_SYN_RECV
)
1810 get_openreq6(seq
, v
, st
->num
);
1812 get_tcp6_sock(seq
, v
, st
->num
);
1817 static const struct file_operations tcp6_afinfo_seq_fops
= {
1818 .owner
= THIS_MODULE
,
1819 .open
= tcp_seq_open
,
1821 .llseek
= seq_lseek
,
1822 .release
= seq_release_net
1825 static struct tcp_seq_afinfo tcp6_seq_afinfo
= {
1828 .seq_fops
= &tcp6_afinfo_seq_fops
,
1830 .show
= tcp6_seq_show
,
1834 int __net_init
tcp6_proc_init(struct net
*net
)
1836 return tcp_proc_register(net
, &tcp6_seq_afinfo
);
1839 void tcp6_proc_exit(struct net
*net
)
1841 tcp_proc_unregister(net
, &tcp6_seq_afinfo
);
1845 static void tcp_v6_clear_sk(struct sock
*sk
, int size
)
1847 struct inet_sock
*inet
= inet_sk(sk
);
1849 /* we do not want to clear pinet6 field, because of RCU lookups */
1850 sk_prot_clear_nulls(sk
, offsetof(struct inet_sock
, pinet6
));
1852 size
-= offsetof(struct inet_sock
, pinet6
) + sizeof(inet
->pinet6
);
1853 memset(&inet
->pinet6
+ 1, 0, size
);
1856 struct proto tcpv6_prot
= {
1858 .owner
= THIS_MODULE
,
1860 .connect
= tcp_v6_connect
,
1861 .disconnect
= tcp_disconnect
,
1862 .accept
= inet_csk_accept
,
1864 .init
= tcp_v6_init_sock
,
1865 .destroy
= tcp_v6_destroy_sock
,
1866 .shutdown
= tcp_shutdown
,
1867 .setsockopt
= tcp_setsockopt
,
1868 .getsockopt
= tcp_getsockopt
,
1869 .recvmsg
= tcp_recvmsg
,
1870 .sendmsg
= tcp_sendmsg
,
1871 .sendpage
= tcp_sendpage
,
1872 .backlog_rcv
= tcp_v6_do_rcv
,
1873 .release_cb
= tcp_release_cb
,
1875 .unhash
= inet_unhash
,
1876 .get_port
= inet_csk_get_port
,
1877 .enter_memory_pressure
= tcp_enter_memory_pressure
,
1878 .stream_memory_free
= tcp_stream_memory_free
,
1879 .sockets_allocated
= &tcp_sockets_allocated
,
1880 .memory_allocated
= &tcp_memory_allocated
,
1881 .memory_pressure
= &tcp_memory_pressure
,
1882 .orphan_count
= &tcp_orphan_count
,
1883 .sysctl_mem
= sysctl_tcp_mem
,
1884 .sysctl_wmem
= sysctl_tcp_wmem
,
1885 .sysctl_rmem
= sysctl_tcp_rmem
,
1886 .max_header
= MAX_TCP_HEADER
,
1887 .obj_size
= sizeof(struct tcp6_sock
),
1888 .slab_flags
= SLAB_DESTROY_BY_RCU
,
1889 .twsk_prot
= &tcp6_timewait_sock_ops
,
1890 .rsk_prot
= &tcp6_request_sock_ops
,
1891 .h
.hashinfo
= &tcp_hashinfo
,
1892 .no_autobind
= true,
1893 #ifdef CONFIG_COMPAT
1894 .compat_setsockopt
= compat_tcp_setsockopt
,
1895 .compat_getsockopt
= compat_tcp_getsockopt
,
1897 .clear_sk
= tcp_v6_clear_sk
,
1898 .diag_destroy
= tcp_abort
,
1901 static const struct inet6_protocol tcpv6_protocol
= {
1902 .early_demux
= tcp_v6_early_demux
,
1903 .handler
= tcp_v6_rcv
,
1904 .err_handler
= tcp_v6_err
,
1905 .flags
= INET6_PROTO_NOPOLICY
|INET6_PROTO_FINAL
,
1908 static struct inet_protosw tcpv6_protosw
= {
1909 .type
= SOCK_STREAM
,
1910 .protocol
= IPPROTO_TCP
,
1911 .prot
= &tcpv6_prot
,
1912 .ops
= &inet6_stream_ops
,
1913 .flags
= INET_PROTOSW_PERMANENT
|
1917 static int __net_init
tcpv6_net_init(struct net
*net
)
1919 return inet_ctl_sock_create(&net
->ipv6
.tcp_sk
, PF_INET6
,
1920 SOCK_RAW
, IPPROTO_TCP
, net
);
1923 static void __net_exit
tcpv6_net_exit(struct net
*net
)
1925 inet_ctl_sock_destroy(net
->ipv6
.tcp_sk
);
1928 static void __net_exit
tcpv6_net_exit_batch(struct list_head
*net_exit_list
)
1930 inet_twsk_purge(&tcp_hashinfo
, &tcp_death_row
, AF_INET6
);
1933 static struct pernet_operations tcpv6_net_ops
= {
1934 .init
= tcpv6_net_init
,
1935 .exit
= tcpv6_net_exit
,
1936 .exit_batch
= tcpv6_net_exit_batch
,
1939 int __init
tcpv6_init(void)
1943 ret
= inet6_add_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
1947 /* register inet6 protocol */
1948 ret
= inet6_register_protosw(&tcpv6_protosw
);
1950 goto out_tcpv6_protocol
;
1952 ret
= register_pernet_subsys(&tcpv6_net_ops
);
1954 goto out_tcpv6_protosw
;
1959 inet6_unregister_protosw(&tcpv6_protosw
);
1961 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);
1965 void tcpv6_exit(void)
1967 unregister_pernet_subsys(&tcpv6_net_ops
);
1968 inet6_unregister_protosw(&tcpv6_protosw
);
1969 inet6_del_protocol(&tcpv6_protocol
, IPPROTO_TCP
);