blob: 3571f2be4470749b9a7c8178fa43a6bf2bac33d8 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Implementation of the Transmission Control Protocol(TCP).
7 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 * IPv4 specific functions
9 *
10 *
11 * code split from:
12 * linux/ipv4/tcp.c
13 * linux/ipv4/tcp_input.c
14 * linux/ipv4/tcp_output.c
15 *
16 * See tcp.c for author information
17 *
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version
21 * 2 of the License, or (at your option) any later version.
22 */
23
24/*
25 * Changes:
26 * David S. Miller : New socket lookup architecture.
27 * This code is dedicated to John Dyson.
28 * David S. Miller : Change semantics of established hash,
29 * half is devoted to TIME_WAIT sockets
30 * and the rest go in the other half.
31 * Andi Kleen : Add support for syncookies and fixed
32 * some bugs: ip options weren't passed to
33 * the TCP layer, missed a check for an
34 * ACK bit.
35 * Andi Kleen : Implemented fast path mtu discovery.
36 * Fixed many serious bugs in the
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -070037 * request_sock handling and moved
Linus Torvalds1da177e2005-04-16 15:20:36 -070038 * most of it into the af independent code.
39 * Added tail drop and some other bugfixes.
Stephen Hemmingercaa20d9a2005-11-10 17:13:47 -080040 * Added new listen semantics.
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 * Mike McLagan : Routing by source
42 * Juan Jose Ciarlante: ip_dynaddr bits
43 * Andi Kleen: various fixes.
44 * Vitaly E. Lavrov : Transparent proxy revived after year
45 * coma.
46 * Andi Kleen : Fix new listen.
47 * Andi Kleen : Fix accept error reporting.
48 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
49 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
50 * a single port at the same time.
51 */
52
Joe Perchesafd465032012-03-12 07:03:32 +000053#define pr_fmt(fmt) "TCP: " fmt
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
Herbert Xueb4dea52008-12-29 23:04:08 -080055#include <linux/bottom_half.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070056#include <linux/types.h>
57#include <linux/fcntl.h>
58#include <linux/module.h>
59#include <linux/random.h>
60#include <linux/cache.h>
61#include <linux/jhash.h>
62#include <linux/init.h>
63#include <linux/times.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090064#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
Eric W. Biederman457c4cb2007-09-12 12:01:34 +020066#include <net/net_namespace.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070067#include <net/icmp.h>
Arnaldo Carvalho de Melo304a1612005-08-09 19:59:20 -070068#include <net/inet_hashtables.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070069#include <net/tcp.h>
Arnaldo Carvalho de Melo20380732005-08-16 02:18:02 -030070#include <net/transp_v6.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070071#include <net/ipv6.h>
72#include <net/inet_common.h>
Arnaldo Carvalho de Melo6d6ee432005-12-13 23:25:19 -080073#include <net/timewait_sock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070074#include <net/xfrm.h>
David S. Miller6e5714e2011-08-03 20:50:44 -070075#include <net/secure_seq.h>
Glauber Costad1a4c0b2011-12-11 21:47:04 +000076#include <net/tcp_memcontrol.h>
Eliezer Tamir076bb0c2013-07-10 17:13:17 +030077#include <net/busy_poll.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79#include <linux/inet.h>
80#include <linux/ipv6.h>
81#include <linux/stddef.h>
82#include <linux/proc_fs.h>
83#include <linux/seq_file.h>
84
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -080085#include <linux/crypto.h>
86#include <linux/scatterlist.h>
87
Brian Haleyab32ea52006-09-22 14:15:41 -070088int sysctl_tcp_tw_reuse __read_mostly;
89int sysctl_tcp_low_latency __read_mostly;
Eric Dumazet4bc2f182010-07-09 21:22:10 +000090EXPORT_SYMBOL(sysctl_tcp_low_latency);
Linus Torvalds1da177e2005-04-16 15:20:36 -070091
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -080092#ifdef CONFIG_TCP_MD5SIG
Eric Dumazeta915da9b2012-01-31 05:18:33 +000093static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key,
Eric Dumazet318cf7a2011-10-24 02:46:04 -040094 __be32 daddr, __be32 saddr, const struct tcphdr *th);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -080095#endif
96
Eric Dumazet5caea4e2008-11-20 00:40:07 -080097struct inet_hashinfo tcp_hashinfo;
Eric Dumazet4bc2f182010-07-09 21:22:10 +000098EXPORT_SYMBOL(tcp_hashinfo);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099
Octavian Purdila936b8bd2014-06-25 17:09:57 +0300100static __u32 tcp_v4_init_sequence(const struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101{
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700102 return secure_tcp_sequence_number(ip_hdr(skb)->daddr,
103 ip_hdr(skb)->saddr,
Arnaldo Carvalho de Meloaa8223c2007-04-10 21:04:22 -0700104 tcp_hdr(skb)->dest,
105 tcp_hdr(skb)->source);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106}
107
Arnaldo Carvalho de Melo6d6ee432005-12-13 23:25:19 -0800108int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp)
109{
110 const struct tcp_timewait_sock *tcptw = tcp_twsk(sktw);
111 struct tcp_sock *tp = tcp_sk(sk);
112
113 /* With PAWS, it is safe from the viewpoint
114 of data integrity. Even without PAWS it is safe provided sequence
115 spaces do not overlap i.e. at data rates <= 80Mbit/sec.
116
117 Actually, the idea is close to VJ's one, only timestamp cache is
118 held not per host, but per port pair and TW bucket is used as state
119 holder.
120
121 If TW bucket has been already destroyed we fall back to VJ's scheme
122 and use initial timestamp retrieved from peer table.
123 */
124 if (tcptw->tw_ts_recent_stamp &&
Ian Morris51456b22015-04-03 09:17:26 +0100125 (!twp || (sysctl_tcp_tw_reuse &&
James Morris9d729f72007-03-04 16:12:44 -0800126 get_seconds() - tcptw->tw_ts_recent_stamp > 1))) {
Arnaldo Carvalho de Melo6d6ee432005-12-13 23:25:19 -0800127 tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2;
128 if (tp->write_seq == 0)
129 tp->write_seq = 1;
130 tp->rx_opt.ts_recent = tcptw->tw_ts_recent;
131 tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp;
132 sock_hold(sktw);
133 return 1;
134 }
135
136 return 0;
137}
Arnaldo Carvalho de Melo6d6ee432005-12-13 23:25:19 -0800138EXPORT_SYMBOL_GPL(tcp_twsk_unique);
139
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140/* This will initiate an outgoing connection. */
141int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
142{
David S. Miller2d7192d2011-04-26 13:28:44 -0700143 struct sockaddr_in *usin = (struct sockaddr_in *)uaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 struct inet_sock *inet = inet_sk(sk);
145 struct tcp_sock *tp = tcp_sk(sk);
David S. Millerdca8b082011-02-24 13:38:12 -0800146 __be16 orig_sport, orig_dport;
Al Virobada8ad2006-09-26 21:27:15 -0700147 __be32 daddr, nexthop;
David S. Millerda905bd2011-05-06 16:11:19 -0700148 struct flowi4 *fl4;
David S. Miller2d7192d2011-04-26 13:28:44 -0700149 struct rtable *rt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150 int err;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000151 struct ip_options_rcu *inet_opt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152
153 if (addr_len < sizeof(struct sockaddr_in))
154 return -EINVAL;
155
156 if (usin->sin_family != AF_INET)
157 return -EAFNOSUPPORT;
158
159 nexthop = daddr = usin->sin_addr.s_addr;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000160 inet_opt = rcu_dereference_protected(inet->inet_opt,
161 sock_owned_by_user(sk));
162 if (inet_opt && inet_opt->opt.srr) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 if (!daddr)
164 return -EINVAL;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000165 nexthop = inet_opt->opt.faddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 }
167
David S. Millerdca8b082011-02-24 13:38:12 -0800168 orig_sport = inet->inet_sport;
169 orig_dport = usin->sin_port;
David S. Millerda905bd2011-05-06 16:11:19 -0700170 fl4 = &inet->cork.fl.u.ip4;
171 rt = ip_route_connect(fl4, nexthop, inet->inet_saddr,
David S. Millerb23dd4f2011-03-02 14:31:35 -0800172 RT_CONN_FLAGS(sk), sk->sk_bound_dev_if,
173 IPPROTO_TCP,
Steffen Klassert0e0d44a2013-08-28 08:04:14 +0200174 orig_sport, orig_dport, sk);
David S. Millerb23dd4f2011-03-02 14:31:35 -0800175 if (IS_ERR(rt)) {
176 err = PTR_ERR(rt);
177 if (err == -ENETUNREACH)
Eric Dumazetf1d8cba2013-11-28 09:51:22 -0800178 IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
David S. Millerb23dd4f2011-03-02 14:31:35 -0800179 return err;
Wei Dong584bdf82007-05-31 22:49:28 -0700180 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181
182 if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) {
183 ip_rt_put(rt);
184 return -ENETUNREACH;
185 }
186
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000187 if (!inet_opt || !inet_opt->opt.srr)
David S. Millerda905bd2011-05-06 16:11:19 -0700188 daddr = fl4->daddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000190 if (!inet->inet_saddr)
David S. Millerda905bd2011-05-06 16:11:19 -0700191 inet->inet_saddr = fl4->saddr;
Eric Dumazetd1e559d2015-03-18 14:05:35 -0700192 sk_rcv_saddr_set(sk, inet->inet_saddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000194 if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195 /* Reset inherited state */
196 tp->rx_opt.ts_recent = 0;
197 tp->rx_opt.ts_recent_stamp = 0;
Pavel Emelyanovee995282012-04-19 03:40:39 +0000198 if (likely(!tp->repair))
199 tp->write_seq = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 }
201
Arnaldo Carvalho de Melo295ff7e2005-08-09 20:44:40 -0700202 if (tcp_death_row.sysctl_tw_recycle &&
David S. Miller81166dd2012-07-10 03:14:24 -0700203 !tp->rx_opt.ts_recent_stamp && fl4->daddr == daddr)
204 tcp_fetch_timewait_stamp(sk, &rt->dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000206 inet->inet_dport = usin->sin_port;
Eric Dumazetd1e559d2015-03-18 14:05:35 -0700207 sk_daddr_set(sk, daddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
Arnaldo Carvalho de Melod83d8462005-12-13 23:26:10 -0800209 inet_csk(sk)->icsk_ext_hdr_len = 0;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +0000210 if (inet_opt)
211 inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
William Allen Simpsonbee7ca92009-11-10 09:51:18 +0000213 tp->rx_opt.mss_clamp = TCP_MSS_DEFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214
215 /* Socket identity is still unknown (sport may be zero).
216 * However we set state to SYN-SENT and not releasing socket
217 * lock select source port, enter ourselves into the hash tables and
218 * complete initialization after this.
219 */
220 tcp_set_state(sk, TCP_SYN_SENT);
Arnaldo Carvalho de Meloa7f5e7f2005-12-13 23:25:31 -0800221 err = inet_hash_connect(&tcp_death_row, sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 if (err)
223 goto failure;
224
Sathya Perla9e7ceb02014-10-22 21:42:01 +0530225 inet_set_txhash(sk);
226
David S. Millerda905bd2011-05-06 16:11:19 -0700227 rt = ip_route_newports(fl4, rt, orig_sport, orig_dport,
David S. Millerb23dd4f2011-03-02 14:31:35 -0800228 inet->inet_sport, inet->inet_dport, sk);
229 if (IS_ERR(rt)) {
230 err = PTR_ERR(rt);
231 rt = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 goto failure;
David S. Millerb23dd4f2011-03-02 14:31:35 -0800233 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 /* OK, now commit destination to socket. */
Herbert Xubcd76112006-06-30 13:36:35 -0700235 sk->sk_gso_type = SKB_GSO_TCPV4;
Changli Gaod8d1f302010-06-10 23:31:35 -0700236 sk_setup_caps(sk, &rt->dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237
Pavel Emelyanovee995282012-04-19 03:40:39 +0000238 if (!tp->write_seq && likely(!tp->repair))
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000239 tp->write_seq = secure_tcp_sequence_number(inet->inet_saddr,
240 inet->inet_daddr,
241 inet->inet_sport,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 usin->sin_port);
243
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000244 inet->inet_id = tp->write_seq ^ jiffies;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245
Andrey Vagin2b916472012-11-22 01:13:58 +0000246 err = tcp_connect(sk);
Pavel Emelyanovee995282012-04-19 03:40:39 +0000247
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 rt = NULL;
249 if (err)
250 goto failure;
251
252 return 0;
253
254failure:
Arnaldo Carvalho de Melo71742592006-11-17 10:57:30 -0200255 /*
256 * This unhashes the socket and releases the local port,
257 * if necessary.
258 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 tcp_set_state(sk, TCP_CLOSE);
260 ip_rt_put(rt);
261 sk->sk_route_caps = 0;
Eric Dumazetc720c7e2009-10-15 06:30:45 +0000262 inet->inet_dport = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 return err;
264}
Eric Dumazet4bc2f182010-07-09 21:22:10 +0000265EXPORT_SYMBOL(tcp_v4_connect);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267/*
Eric Dumazet563d34d2012-07-23 09:48:52 +0200268 * This routine reacts to ICMP_FRAG_NEEDED mtu indications as defined in RFC1191.
269 * It can be called through tcp_release_cb() if socket was owned by user
270 * at the time tcp_v4_err() was called to handle ICMP message.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 */
Neal Cardwell4fab9072014-08-14 12:40:05 -0400272void tcp_v4_mtu_reduced(struct sock *sk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273{
274 struct dst_entry *dst;
275 struct inet_sock *inet = inet_sk(sk);
Eric Dumazet563d34d2012-07-23 09:48:52 +0200276 u32 mtu = tcp_sk(sk)->mtu_info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277
David S. Miller80d0a692012-07-16 03:28:06 -0700278 dst = inet_csk_update_pmtu(sk, mtu);
279 if (!dst)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 return;
281
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 /* Something is about to be wrong... Remember soft error
283 * for the case, if this connection will not able to recover.
284 */
285 if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst))
286 sk->sk_err_soft = EMSGSIZE;
287
288 mtu = dst_mtu(dst);
289
290 if (inet->pmtudisc != IP_PMTUDISC_DONT &&
Hannes Frederic Sowa482fc602013-11-05 02:24:17 +0100291 ip_sk_accept_pmtu(sk) &&
Arnaldo Carvalho de Melod83d8462005-12-13 23:26:10 -0800292 inet_csk(sk)->icsk_pmtu_cookie > mtu) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 tcp_sync_mss(sk, mtu);
294
295 /* Resend the TCP packet because it's
296 * clear that the old packet has been
297 * dropped. This is the new "fast" path mtu
298 * discovery.
299 */
300 tcp_simple_retransmit(sk);
301 } /* else let the usual retransmit timer handle it */
302}
Neal Cardwell4fab9072014-08-14 12:40:05 -0400303EXPORT_SYMBOL(tcp_v4_mtu_reduced);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304
David S. Miller55be7a92012-07-11 21:27:49 -0700305static void do_redirect(struct sk_buff *skb, struct sock *sk)
306{
307 struct dst_entry *dst = __sk_dst_check(sk, 0);
308
David S. Miller1ed5c482012-07-12 00:41:25 -0700309 if (dst)
David S. Miller6700c272012-07-17 03:29:28 -0700310 dst->ops->redirect(dst, sk, skb);
David S. Miller55be7a92012-07-11 21:27:49 -0700311}
312
Eric Dumazet26e37362015-03-22 10:22:22 -0700313
314/* handle ICMP messages on TCP_NEW_SYN_RECV request sockets */
315void tcp_req_err(struct sock *sk, u32 seq)
316{
317 struct request_sock *req = inet_reqsk(sk);
318 struct net *net = sock_net(sk);
319
320 /* ICMPs are not backlogged, hence we cannot get
321 * an established socket here.
322 */
323 WARN_ON(req->sk);
324
325 if (seq != tcp_rsk(req)->snt_isn) {
326 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
Fan Duc6973662015-03-23 15:00:41 -0700327 reqsk_put(req);
Eric Dumazet26e37362015-03-22 10:22:22 -0700328 } else {
329 /*
330 * Still in SYN_RECV, just remove it silently.
331 * There is no good way to pass the error to the newly
332 * created socket, and POSIX does not want network
333 * errors returned from accept().
334 */
Eric Dumazet26e37362015-03-22 10:22:22 -0700335 NET_INC_STATS_BH(net, LINUX_MIB_LISTENDROPS);
Fan Duc6973662015-03-23 15:00:41 -0700336 inet_csk_reqsk_queue_drop(req->rsk_listener, req);
Eric Dumazet26e37362015-03-22 10:22:22 -0700337 }
Eric Dumazet26e37362015-03-22 10:22:22 -0700338}
339EXPORT_SYMBOL(tcp_req_err);
340
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341/*
342 * This routine is called by the ICMP module when it gets some
343 * sort of error condition. If err < 0 then the socket should
344 * be closed and the error returned to the user. If err > 0
345 * it's just the icmp type << 8 | icmp code. After adjustment
346 * header points to the first 8 bytes of the tcp header. We need
347 * to find the appropriate port.
348 *
349 * The locking strategy used here is very "optimistic". When
350 * someone else accesses the socket the ICMP is just dropped
351 * and for some paths there is no check at all.
352 * A more general error queue to queue errors for later handling
353 * is probably better.
354 *
355 */
356
Damian Lukowski4d1a2d92009-08-26 00:16:27 +0000357void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358{
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000359 const struct iphdr *iph = (const struct iphdr *)icmp_skb->data;
Damian Lukowski4d1a2d92009-08-26 00:16:27 +0000360 struct tcphdr *th = (struct tcphdr *)(icmp_skb->data + (iph->ihl << 2));
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000361 struct inet_connection_sock *icsk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 struct tcp_sock *tp;
363 struct inet_sock *inet;
Damian Lukowski4d1a2d92009-08-26 00:16:27 +0000364 const int type = icmp_hdr(icmp_skb)->type;
365 const int code = icmp_hdr(icmp_skb)->code;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 struct sock *sk;
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000367 struct sk_buff *skb;
Yuchung Cheng0a672f72014-05-11 20:22:12 -0700368 struct request_sock *fastopen;
369 __u32 seq, snd_una;
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000370 __u32 remaining;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 int err;
Damian Lukowski4d1a2d92009-08-26 00:16:27 +0000372 struct net *net = dev_net(icmp_skb->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373
Eric Dumazet26e37362015-03-22 10:22:22 -0700374 sk = __inet_lookup_established(net, &tcp_hashinfo, iph->daddr,
375 th->dest, iph->saddr, ntohs(th->source),
376 inet_iif(icmp_skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377 if (!sk) {
Pavel Emelyanovdcfc23c2008-07-14 23:03:00 -0700378 ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 return;
380 }
381 if (sk->sk_state == TCP_TIME_WAIT) {
YOSHIFUJI Hideaki9469c7b2006-10-10 19:41:46 -0700382 inet_twsk_put(inet_twsk(sk));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383 return;
384 }
Eric Dumazet26e37362015-03-22 10:22:22 -0700385 seq = ntohl(th->seq);
386 if (sk->sk_state == TCP_NEW_SYN_RECV)
387 return tcp_req_err(sk, seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388
389 bh_lock_sock(sk);
390 /* If too many ICMPs get dropped on busy
391 * servers this needs to be solved differently.
Eric Dumazet563d34d2012-07-23 09:48:52 +0200392 * We do take care of PMTU discovery (RFC1191) special case :
393 * we can receive locally generated ICMP messages while socket is held.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 */
Eric Dumazetb74aa932013-01-19 16:10:37 +0000395 if (sock_owned_by_user(sk)) {
396 if (!(type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED))
397 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
398 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 if (sk->sk_state == TCP_CLOSE)
400 goto out;
401
stephen hemminger97e3ecd12010-03-18 11:27:32 +0000402 if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) {
403 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
404 goto out;
405 }
406
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000407 icsk = inet_csk(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 tp = tcp_sk(sk);
Yuchung Cheng0a672f72014-05-11 20:22:12 -0700409 /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */
410 fastopen = tp->fastopen_rsk;
411 snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 if (sk->sk_state != TCP_LISTEN &&
Yuchung Cheng0a672f72014-05-11 20:22:12 -0700413 !between(seq, snd_una, tp->snd_nxt)) {
Pavel Emelyanovde0744a2008-07-16 20:31:16 -0700414 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 goto out;
416 }
417
418 switch (type) {
David S. Miller55be7a92012-07-11 21:27:49 -0700419 case ICMP_REDIRECT:
420 do_redirect(icmp_skb, sk);
421 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422 case ICMP_SOURCE_QUENCH:
423 /* Just silently ignore these. */
424 goto out;
425 case ICMP_PARAMETERPROB:
426 err = EPROTO;
427 break;
428 case ICMP_DEST_UNREACH:
429 if (code > NR_ICMP_UNREACH)
430 goto out;
431
432 if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */
Eric Dumazet0d4f0602013-03-18 07:01:28 +0000433 /* We are not interested in TCP_LISTEN and open_requests
434 * (SYN-ACKs send out by Linux are always <576bytes so
435 * they should go through unfragmented).
436 */
437 if (sk->sk_state == TCP_LISTEN)
438 goto out;
439
Eric Dumazet563d34d2012-07-23 09:48:52 +0200440 tp->mtu_info = info;
Eric Dumazet144d56e2012-08-20 00:22:46 +0000441 if (!sock_owned_by_user(sk)) {
Eric Dumazet563d34d2012-07-23 09:48:52 +0200442 tcp_v4_mtu_reduced(sk);
Eric Dumazet144d56e2012-08-20 00:22:46 +0000443 } else {
444 if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &tp->tsq_flags))
445 sock_hold(sk);
446 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 goto out;
448 }
449
450 err = icmp_err_convert[code].errno;
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000451 /* check if icmp_skb allows revert of backoff
452 * (see draft-zimmermann-tcp-lcd) */
453 if (code != ICMP_NET_UNREACH && code != ICMP_HOST_UNREACH)
454 break;
455 if (seq != tp->snd_una || !icsk->icsk_retransmits ||
Yuchung Cheng0a672f72014-05-11 20:22:12 -0700456 !icsk->icsk_backoff || fastopen)
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000457 break;
458
David S. Miller8f49c272010-11-12 13:35:00 -0800459 if (sock_owned_by_user(sk))
460 break;
461
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000462 icsk->icsk_backoff--;
Eric Dumazetfcdd1cf2014-09-22 13:19:44 -0700463 icsk->icsk_rto = tp->srtt_us ? __tcp_set_rto(tp) :
464 TCP_TIMEOUT_INIT;
465 icsk->icsk_rto = inet_csk_rto_backoff(icsk, TCP_RTO_MAX);
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000466
467 skb = tcp_write_queue_head(sk);
468 BUG_ON(!skb);
469
Eric Dumazet7faee5c2014-09-05 15:33:33 -0700470 remaining = icsk->icsk_rto -
471 min(icsk->icsk_rto,
472 tcp_time_stamp - tcp_skb_timestamp(skb));
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000473
474 if (remaining) {
475 inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
476 remaining, TCP_RTO_MAX);
Damian Lukowskif1ecd5d2009-08-26 00:16:31 +0000477 } else {
478 /* RTO revert clocked out retransmission.
479 * Will retransmit now */
480 tcp_retransmit_timer(sk);
481 }
482
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483 break;
484 case ICMP_TIME_EXCEEDED:
485 err = EHOSTUNREACH;
486 break;
487 default:
488 goto out;
489 }
490
491 switch (sk->sk_state) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 case TCP_SYN_SENT:
Yuchung Cheng0a672f72014-05-11 20:22:12 -0700493 case TCP_SYN_RECV:
494 /* Only in fast or simultaneous open. If a fast open socket is
495 * is already accepted it is treated as a connected one below.
496 */
Ian Morris51456b22015-04-03 09:17:26 +0100497 if (fastopen && !fastopen->sk)
Yuchung Cheng0a672f72014-05-11 20:22:12 -0700498 break;
499
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500 if (!sock_owned_by_user(sk)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501 sk->sk_err = err;
502
503 sk->sk_error_report(sk);
504
505 tcp_done(sk);
506 } else {
507 sk->sk_err_soft = err;
508 }
509 goto out;
510 }
511
512 /* If we've already connected we will keep trying
513 * until we time out, or the user gives up.
514 *
515 * rfc1122 4.2.3.9 allows to consider as hard errors
516 * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too,
517 * but it is obsoleted by pmtu discovery).
518 *
519 * Note, that in modern internet, where routing is unreliable
520 * and in each dark corner broken firewalls sit, sending random
521 * errors ordered by their masters even this two messages finally lose
522 * their original sense (even Linux sends invalid PORT_UNREACHs)
523 *
524 * Now we are in compliance with RFCs.
525 * --ANK (980905)
526 */
527
528 inet = inet_sk(sk);
529 if (!sock_owned_by_user(sk) && inet->recverr) {
530 sk->sk_err = err;
531 sk->sk_error_report(sk);
532 } else { /* Only an error on timeout */
533 sk->sk_err_soft = err;
534 }
535
536out:
537 bh_unlock_sock(sk);
538 sock_put(sk);
539}
540
Daniel Borkmann28850dc2013-06-07 05:11:46 +0000541void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542{
Arnaldo Carvalho de Meloaa8223c2007-04-10 21:04:22 -0700543 struct tcphdr *th = tcp_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544
Patrick McHardy84fa7932006-08-29 16:44:56 -0700545 if (skb->ip_summed == CHECKSUM_PARTIAL) {
Herbert Xu419f9f82010-04-11 02:15:53 +0000546 th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0);
Herbert Xu663ead32007-04-09 11:59:07 -0700547 skb->csum_start = skb_transport_header(skb) - skb->head;
Al Viroff1dcad2006-11-20 18:07:29 -0800548 skb->csum_offset = offsetof(struct tcphdr, check);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 } else {
Herbert Xu419f9f82010-04-11 02:15:53 +0000550 th->check = tcp_v4_check(skb->len, saddr, daddr,
Joe Perches07f07572008-11-19 15:44:53 -0800551 csum_partial(th,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 th->doff << 2,
553 skb->csum));
554 }
555}
556
Herbert Xu419f9f82010-04-11 02:15:53 +0000557/* This routine computes an IPv4 TCP checksum. */
Herbert Xubb296242010-04-11 02:15:55 +0000558void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb)
Herbert Xu419f9f82010-04-11 02:15:53 +0000559{
Eric Dumazetcf533ea2011-10-21 05:22:42 -0400560 const struct inet_sock *inet = inet_sk(sk);
Herbert Xu419f9f82010-04-11 02:15:53 +0000561
562 __tcp_v4_send_check(skb, inet->inet_saddr, inet->inet_daddr);
563}
Eric Dumazet4bc2f182010-07-09 21:22:10 +0000564EXPORT_SYMBOL(tcp_v4_send_check);
Herbert Xu419f9f82010-04-11 02:15:53 +0000565
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566/*
567 * This routine will send an RST to the other tcp.
568 *
569 * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.)
570 * for reset.
571 * Answer: if a packet caused RST, it is not for a socket
572 * existing in our system, if it is matched to a socket,
573 * it is just duplicate segment or bug in other side's TCP.
574 * So that we build reply only basing on parameters
575 * arrived with segment.
576 * Exception: precedence violation. We do not implement it in any case.
577 */
578
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800579static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580{
Eric Dumazetcf533ea2011-10-21 05:22:42 -0400581 const struct tcphdr *th = tcp_hdr(skb);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800582 struct {
583 struct tcphdr th;
584#ifdef CONFIG_TCP_MD5SIG
Al Viro714e85b2006-11-14 20:51:49 -0800585 __be32 opt[(TCPOLEN_MD5SIG_ALIGNED >> 2)];
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800586#endif
587 } rep;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 struct ip_reply_arg arg;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800589#ifdef CONFIG_TCP_MD5SIG
590 struct tcp_md5sig_key *key;
Shawn Lu658ddaa2012-01-31 22:35:48 +0000591 const __u8 *hash_location = NULL;
592 unsigned char newhash[16];
593 int genhash;
594 struct sock *sk1 = NULL;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800595#endif
Pavel Emelyanova86b1e32008-07-16 20:20:58 -0700596 struct net *net;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597
598 /* Never send a reset in response to a reset. */
599 if (th->rst)
600 return;
601
Eric Dumazetc3658e82014-11-25 07:40:04 -0800602 /* If sk not NULL, it means we did a successful lookup and incoming
603 * route had to be correct. prequeue might have dropped our dst.
604 */
605 if (!sk && skb_rtable(skb)->rt_type != RTN_LOCAL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 return;
607
608 /* Swap the send and the receive. */
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800609 memset(&rep, 0, sizeof(rep));
610 rep.th.dest = th->source;
611 rep.th.source = th->dest;
612 rep.th.doff = sizeof(struct tcphdr) / 4;
613 rep.th.rst = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614
615 if (th->ack) {
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800616 rep.th.seq = th->ack_seq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 } else {
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800618 rep.th.ack = 1;
619 rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin +
620 skb->len - (th->doff << 2));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 }
622
Arnaldo Carvalho de Melo71742592006-11-17 10:57:30 -0200623 memset(&arg, 0, sizeof(arg));
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800624 arg.iov[0].iov_base = (unsigned char *)&rep;
625 arg.iov[0].iov_len = sizeof(rep.th);
626
Eric Dumazet0f85fea2014-12-09 09:56:08 -0800627 net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800628#ifdef CONFIG_TCP_MD5SIG
Shawn Lu658ddaa2012-01-31 22:35:48 +0000629 hash_location = tcp_parse_md5sig_option(th);
630 if (!sk && hash_location) {
631 /*
632 * active side is lost. Try to find listening socket through
633 * source port, and then find md5 key through listening socket.
634 * we are not loose security here:
635 * Incoming packet is checked with md5 hash with finding key,
636 * no RST generated if md5 hash doesn't match.
637 */
Eric Dumazet0f85fea2014-12-09 09:56:08 -0800638 sk1 = __inet_lookup_listener(net,
Tom Herbertda5e3632013-01-22 09:50:24 +0000639 &tcp_hashinfo, ip_hdr(skb)->saddr,
640 th->source, ip_hdr(skb)->daddr,
Shawn Lu658ddaa2012-01-31 22:35:48 +0000641 ntohs(th->source), inet_iif(skb));
642 /* don't send rst if it can't find key */
643 if (!sk1)
644 return;
645 rcu_read_lock();
646 key = tcp_md5_do_lookup(sk1, (union tcp_md5_addr *)
647 &ip_hdr(skb)->saddr, AF_INET);
648 if (!key)
649 goto release_sk1;
650
Eric Dumazet39f8e582015-03-24 15:58:55 -0700651 genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb);
Shawn Lu658ddaa2012-01-31 22:35:48 +0000652 if (genhash || memcmp(hash_location, newhash, 16) != 0)
653 goto release_sk1;
654 } else {
655 key = sk ? tcp_md5_do_lookup(sk, (union tcp_md5_addr *)
656 &ip_hdr(skb)->saddr,
657 AF_INET) : NULL;
658 }
659
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800660 if (key) {
661 rep.opt[0] = htonl((TCPOPT_NOP << 24) |
662 (TCPOPT_NOP << 16) |
663 (TCPOPT_MD5SIG << 8) |
664 TCPOLEN_MD5SIG);
665 /* Update length and the length the header thinks exists */
666 arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED;
667 rep.th.doff = arg.iov[0].iov_len / 4;
668
Adam Langley49a72df2008-07-19 00:01:42 -0700669 tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[1],
Ilpo Järvinen78e645cb2008-10-09 14:37:47 -0700670 key, ip_hdr(skb)->saddr,
671 ip_hdr(skb)->daddr, &rep.th);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800672 }
673#endif
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700674 arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr,
675 ip_hdr(skb)->saddr, /* XXX */
Ilpo Järvinen52cd5752008-10-08 11:34:06 -0700676 arg.iov[0].iov_len, IPPROTO_TCP, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 arg.csumoffset = offsetof(struct tcphdr, check) / 2;
KOVACS Krisztian88ef4a52008-10-01 07:41:00 -0700678 arg.flags = (sk && inet_sk(sk)->transparent) ? IP_REPLY_ARG_NOSRCCHECK : 0;
Shawn Lue2446ea2012-02-04 12:38:09 +0000679 /* When socket is gone, all binding information is lost.
Alexey Kuznetsov4c675252012-10-12 04:34:17 +0000680 * routing might fail in this case. No choice here, if we choose to force
681 * input interface, we will misroute in case of asymmetric route.
Shawn Lue2446ea2012-02-04 12:38:09 +0000682 */
Alexey Kuznetsov4c675252012-10-12 04:34:17 +0000683 if (sk)
684 arg.bound_dev_if = sk->sk_bound_dev_if;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685
Eric Dumazet66b13d92011-10-24 03:06:21 -0400686 arg.tos = ip_hdr(skb)->tos;
Eric Dumazetbdbbb852015-01-29 21:35:05 -0800687 ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
688 skb, &TCP_SKB_CB(skb)->header.h4.opt,
Eric Dumazet24a2d432014-09-27 09:50:55 -0700689 ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
690 &arg, arg.iov[0].iov_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691
Pavel Emelyanov63231bd2008-07-16 20:22:25 -0700692 TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS);
693 TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS);
Shawn Lu658ddaa2012-01-31 22:35:48 +0000694
695#ifdef CONFIG_TCP_MD5SIG
696release_sk1:
697 if (sk1) {
698 rcu_read_unlock();
699 sock_put(sk1);
700 }
701#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702}
703
704/* The code following below sending ACKs in SYN-RECV and TIME-WAIT states
705 outside socket context is ugly, certainly. What can I do?
706 */
707
YOSHIFUJI Hideaki9501f972008-04-18 12:45:16 +0900708static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack,
Andrey Vaginee684b62013-02-11 05:50:19 +0000709 u32 win, u32 tsval, u32 tsecr, int oif,
KOVACS Krisztian88ef4a52008-10-01 07:41:00 -0700710 struct tcp_md5sig_key *key,
Eric Dumazet66b13d92011-10-24 03:06:21 -0400711 int reply_flags, u8 tos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712{
Eric Dumazetcf533ea2011-10-21 05:22:42 -0400713 const struct tcphdr *th = tcp_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714 struct {
715 struct tcphdr th;
Al Viro714e85b2006-11-14 20:51:49 -0800716 __be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800717#ifdef CONFIG_TCP_MD5SIG
Al Viro714e85b2006-11-14 20:51:49 -0800718 + (TCPOLEN_MD5SIG_ALIGNED >> 2)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800719#endif
720 ];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721 } rep;
722 struct ip_reply_arg arg;
Eric Dumazetadf30902009-06-02 05:19:30 +0000723 struct net *net = dev_net(skb_dst(skb)->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724
725 memset(&rep.th, 0, sizeof(struct tcphdr));
Arnaldo Carvalho de Melo71742592006-11-17 10:57:30 -0200726 memset(&arg, 0, sizeof(arg));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727
728 arg.iov[0].iov_base = (unsigned char *)&rep;
729 arg.iov[0].iov_len = sizeof(rep.th);
Andrey Vaginee684b62013-02-11 05:50:19 +0000730 if (tsecr) {
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800731 rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
732 (TCPOPT_TIMESTAMP << 8) |
733 TCPOLEN_TIMESTAMP);
Andrey Vaginee684b62013-02-11 05:50:19 +0000734 rep.opt[1] = htonl(tsval);
735 rep.opt[2] = htonl(tsecr);
Craig Schlentercb48cfe2007-01-09 00:11:15 -0800736 arg.iov[0].iov_len += TCPOLEN_TSTAMP_ALIGNED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737 }
738
739 /* Swap the send and the receive. */
740 rep.th.dest = th->source;
741 rep.th.source = th->dest;
742 rep.th.doff = arg.iov[0].iov_len / 4;
743 rep.th.seq = htonl(seq);
744 rep.th.ack_seq = htonl(ack);
745 rep.th.ack = 1;
746 rep.th.window = htons(win);
747
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800748#ifdef CONFIG_TCP_MD5SIG
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800749 if (key) {
Andrey Vaginee684b62013-02-11 05:50:19 +0000750 int offset = (tsecr) ? 3 : 0;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800751
752 rep.opt[offset++] = htonl((TCPOPT_NOP << 24) |
753 (TCPOPT_NOP << 16) |
754 (TCPOPT_MD5SIG << 8) |
755 TCPOLEN_MD5SIG);
756 arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED;
757 rep.th.doff = arg.iov[0].iov_len/4;
758
Adam Langley49a72df2008-07-19 00:01:42 -0700759 tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[offset],
Adam Langley90b7e112008-07-31 20:49:48 -0700760 key, ip_hdr(skb)->saddr,
761 ip_hdr(skb)->daddr, &rep.th);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800762 }
763#endif
KOVACS Krisztian88ef4a52008-10-01 07:41:00 -0700764 arg.flags = reply_flags;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700765 arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr,
766 ip_hdr(skb)->saddr, /* XXX */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767 arg.iov[0].iov_len, IPPROTO_TCP, 0);
768 arg.csumoffset = offsetof(struct tcphdr, check) / 2;
YOSHIFUJI Hideaki9501f972008-04-18 12:45:16 +0900769 if (oif)
770 arg.bound_dev_if = oif;
Eric Dumazet66b13d92011-10-24 03:06:21 -0400771 arg.tos = tos;
Eric Dumazetbdbbb852015-01-29 21:35:05 -0800772 ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk),
773 skb, &TCP_SKB_CB(skb)->header.h4.opt,
Eric Dumazet24a2d432014-09-27 09:50:55 -0700774 ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
775 &arg, arg.iov[0].iov_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776
Pavel Emelyanov63231bd2008-07-16 20:22:25 -0700777 TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778}
779
780static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb)
781{
Arnaldo Carvalho de Melo8feaf0c02005-08-09 20:09:30 -0700782 struct inet_timewait_sock *tw = inet_twsk(sk);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800783 struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784
YOSHIFUJI Hideaki9501f972008-04-18 12:45:16 +0900785 tcp_v4_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
Arnaldo Carvalho de Melo71742592006-11-17 10:57:30 -0200786 tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
Andrey Vaginee684b62013-02-11 05:50:19 +0000787 tcp_time_stamp + tcptw->tw_ts_offset,
YOSHIFUJI Hideaki9501f972008-04-18 12:45:16 +0900788 tcptw->tw_ts_recent,
789 tw->tw_bound_dev_if,
KOVACS Krisztian88ef4a52008-10-01 07:41:00 -0700790 tcp_twsk_md5_key(tcptw),
Eric Dumazet66b13d92011-10-24 03:06:21 -0400791 tw->tw_transparent ? IP_REPLY_ARG_NOSRCCHECK : 0,
792 tw->tw_tos
YOSHIFUJI Hideaki9501f972008-04-18 12:45:16 +0900793 );
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794
Arnaldo Carvalho de Melo8feaf0c02005-08-09 20:09:30 -0700795 inet_twsk_put(tw);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796}
797
Gui Jianfeng6edafaa2008-08-06 23:50:04 -0700798static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
Arnaldo Carvalho de Melo71742592006-11-17 10:57:30 -0200799 struct request_sock *req)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800{
Jerry Chu168a8f52012-08-31 12:29:13 +0000801 /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV
802 * sk->sk_state == TCP_SYN_RECV -> for Fast Open.
803 */
804 tcp_v4_send_ack(skb, (sk->sk_state == TCP_LISTEN) ?
805 tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt,
806 tcp_rsk(req)->rcv_nxt, req->rcv_wnd,
Andrey Vaginee684b62013-02-11 05:50:19 +0000807 tcp_time_stamp,
YOSHIFUJI Hideaki9501f972008-04-18 12:45:16 +0900808 req->ts_recent,
809 0,
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000810 tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->daddr,
811 AF_INET),
Eric Dumazet66b13d92011-10-24 03:06:21 -0400812 inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0,
813 ip_hdr(skb)->tos);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814}
815
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816/*
Kris Katterjohn9bf1d832008-02-17 22:29:19 -0800817 * Send a SYN-ACK after having received a SYN.
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -0700818 * This still operates on a request_sock only, not on a big
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819 * socket.
820 */
Octavian Purdila72659ec2010-01-17 19:09:39 -0800821static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
Octavian Purdilad6274bd2014-06-25 17:09:58 +0300822 struct flowi *fl,
Octavian Purdila72659ec2010-01-17 19:09:39 -0800823 struct request_sock *req,
Yuchung Cheng843f4a52014-05-11 20:22:11 -0700824 u16 queue_mapping,
825 struct tcp_fastopen_cookie *foc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826{
Arnaldo Carvalho de Melo2e6599c2005-06-18 22:46:52 -0700827 const struct inet_request_sock *ireq = inet_rsk(req);
David S. Miller6bd023f2011-05-18 18:32:03 -0400828 struct flowi4 fl4;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829 int err = -1;
Weilong Chend41db5a2013-12-23 14:37:28 +0800830 struct sk_buff *skb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831
832 /* First, grab a route. */
David S. Millerba3f7f02012-07-17 14:02:46 -0700833 if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL)
Denis V. Lunevfd80eb92008-02-29 11:43:03 -0800834 return -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835
Yuchung Cheng843f4a52014-05-11 20:22:11 -0700836 skb = tcp_make_synack(sk, dst, req, foc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837
838 if (skb) {
Eric Dumazet634fb9792013-10-09 15:21:29 -0700839 __tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840
Eric Dumazetfff32692012-06-01 01:47:50 +0000841 skb_set_queue_mapping(skb, queue_mapping);
Eric Dumazet634fb9792013-10-09 15:21:29 -0700842 err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr,
843 ireq->ir_rmt_addr,
Arnaldo Carvalho de Melo2e6599c2005-06-18 22:46:52 -0700844 ireq->opt);
Gerrit Renkerb9df3cb2006-11-14 11:21:36 -0200845 err = net_xmit_eval(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 }
847
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 return err;
849}
850
851/*
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -0700852 * IPv4 request_sock destructor.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853 */
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -0700854static void tcp_v4_reqsk_destructor(struct request_sock *req)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855{
Jesper Juhla51482b2005-11-08 09:41:34 -0800856 kfree(inet_rsk(req)->opt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857}
858
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800860#ifdef CONFIG_TCP_MD5SIG
861/*
862 * RFC2385 MD5 checksumming requires a mapping of
863 * IP address->MD5 Key.
864 * We need to maintain these in the sk structure.
865 */
866
867/* Find the Key structure for an address. */
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000868struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk,
869 const union tcp_md5_addr *addr,
870 int family)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800871{
Eric Dumazetfd3a1542015-03-24 15:58:56 -0700872 const struct tcp_sock *tp = tcp_sk(sk);
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000873 struct tcp_md5sig_key *key;
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000874 unsigned int size = sizeof(struct in_addr);
Eric Dumazetfd3a1542015-03-24 15:58:56 -0700875 const struct tcp_md5sig_info *md5sig;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800876
Eric Dumazeta8afca02012-01-31 18:45:40 +0000877 /* caller either holds rcu_read_lock() or socket lock */
878 md5sig = rcu_dereference_check(tp->md5sig_info,
Eric Dumazetb4fb05e2012-03-07 04:45:43 +0000879 sock_owned_by_user(sk) ||
880 lockdep_is_held(&sk->sk_lock.slock));
Eric Dumazeta8afca02012-01-31 18:45:40 +0000881 if (!md5sig)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800882 return NULL;
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000883#if IS_ENABLED(CONFIG_IPV6)
884 if (family == AF_INET6)
885 size = sizeof(struct in6_addr);
886#endif
Sasha Levinb67bfe02013-02-27 17:06:00 -0800887 hlist_for_each_entry_rcu(key, &md5sig->head, node) {
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000888 if (key->family != family)
889 continue;
890 if (!memcmp(&key->addr, addr, size))
891 return key;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800892 }
893 return NULL;
894}
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000895EXPORT_SYMBOL(tcp_md5_do_lookup);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800896
897struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk,
Eric Dumazetfd3a1542015-03-24 15:58:56 -0700898 const struct sock *addr_sk)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800899{
Eric Dumazetb52e6922015-04-09 14:36:42 -0700900 const union tcp_md5_addr *addr;
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000901
Eric Dumazetb52e6922015-04-09 14:36:42 -0700902 addr = (const union tcp_md5_addr *)&addr_sk->sk_daddr;
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000903 return tcp_md5_do_lookup(sk, addr, AF_INET);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800904}
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800905EXPORT_SYMBOL(tcp_v4_md5_lookup);
906
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800907/* This can be called on a newly created socket, from other files */
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000908int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
909 int family, const u8 *newkey, u8 newkeylen, gfp_t gfp)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800910{
911 /* Add Key to the list */
Matthias M. Dellwegb0a713e2007-10-29 20:55:27 -0700912 struct tcp_md5sig_key *key;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800913 struct tcp_sock *tp = tcp_sk(sk);
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000914 struct tcp_md5sig_info *md5sig;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800915
Aydin Arikc0353c72013-06-14 18:56:31 +1200916 key = tcp_md5_do_lookup(sk, addr, family);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800917 if (key) {
918 /* Pre-existing entry - just update that one. */
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000919 memcpy(key->key, newkey, newkeylen);
Matthias M. Dellwegb0a713e2007-10-29 20:55:27 -0700920 key->keylen = newkeylen;
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000921 return 0;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800922 }
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000923
Eric Dumazeta8afca02012-01-31 18:45:40 +0000924 md5sig = rcu_dereference_protected(tp->md5sig_info,
925 sock_owned_by_user(sk));
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000926 if (!md5sig) {
927 md5sig = kmalloc(sizeof(*md5sig), gfp);
928 if (!md5sig)
929 return -ENOMEM;
930
931 sk_nocaps_add(sk, NETIF_F_GSO_MASK);
932 INIT_HLIST_HEAD(&md5sig->head);
Eric Dumazeta8afca02012-01-31 18:45:40 +0000933 rcu_assign_pointer(tp->md5sig_info, md5sig);
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000934 }
935
Eric Dumazet5f3d9cb2012-01-31 10:56:48 +0000936 key = sock_kmalloc(sk, sizeof(*key), gfp);
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000937 if (!key)
938 return -ENOMEM;
Eric Dumazet71cea172013-05-20 06:52:26 +0000939 if (!tcp_alloc_md5sig_pool()) {
Eric Dumazet5f3d9cb2012-01-31 10:56:48 +0000940 sock_kfree_s(sk, key, sizeof(*key));
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000941 return -ENOMEM;
942 }
943
944 memcpy(key->key, newkey, newkeylen);
945 key->keylen = newkeylen;
946 key->family = family;
947 memcpy(&key->addr, addr,
948 (family == AF_INET6) ? sizeof(struct in6_addr) :
949 sizeof(struct in_addr));
950 hlist_add_head_rcu(&key->node, &md5sig->head);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800951 return 0;
952}
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000953EXPORT_SYMBOL(tcp_md5_do_add);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800954
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000955int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800956{
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000957 struct tcp_md5sig_key *key;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800958
Aydin Arikc0353c72013-06-14 18:56:31 +1200959 key = tcp_md5_do_lookup(sk, addr, family);
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000960 if (!key)
961 return -ENOENT;
962 hlist_del_rcu(&key->node);
Eric Dumazet5f3d9cb2012-01-31 10:56:48 +0000963 atomic_sub(sizeof(*key), &sk->sk_omem_alloc);
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000964 kfree_rcu(key, rcu);
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000965 return 0;
966}
967EXPORT_SYMBOL(tcp_md5_do_del);
968
stephen hemmingere0683e702012-10-26 14:31:40 +0000969static void tcp_clear_md5_list(struct sock *sk)
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000970{
971 struct tcp_sock *tp = tcp_sk(sk);
972 struct tcp_md5sig_key *key;
Sasha Levinb67bfe02013-02-27 17:06:00 -0800973 struct hlist_node *n;
Eric Dumazeta8afca02012-01-31 18:45:40 +0000974 struct tcp_md5sig_info *md5sig;
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000975
Eric Dumazeta8afca02012-01-31 18:45:40 +0000976 md5sig = rcu_dereference_protected(tp->md5sig_info, 1);
977
Sasha Levinb67bfe02013-02-27 17:06:00 -0800978 hlist_for_each_entry_safe(key, n, &md5sig->head, node) {
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000979 hlist_del_rcu(&key->node);
Eric Dumazet5f3d9cb2012-01-31 10:56:48 +0000980 atomic_sub(sizeof(*key), &sk->sk_omem_alloc);
Eric Dumazeta915da9b2012-01-31 05:18:33 +0000981 kfree_rcu(key, rcu);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800982 }
983}
984
Arnaldo Carvalho de Melo71742592006-11-17 10:57:30 -0200985static int tcp_v4_parse_md5_keys(struct sock *sk, char __user *optval,
986 int optlen)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800987{
988 struct tcp_md5sig cmd;
989 struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800990
991 if (optlen < sizeof(cmd))
992 return -EINVAL;
993
Arnaldo Carvalho de Melo71742592006-11-17 10:57:30 -0200994 if (copy_from_user(&cmd, optval, sizeof(cmd)))
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -0800995 return -EFAULT;
996
997 if (sin->sin_family != AF_INET)
998 return -EINVAL;
999
Dmitry Popov64a124e2014-08-03 22:45:19 +04001000 if (!cmd.tcpm_keylen)
Eric Dumazeta915da9b2012-01-31 05:18:33 +00001001 return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr,
1002 AF_INET);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001003
1004 if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN)
1005 return -EINVAL;
1006
Eric Dumazeta915da9b2012-01-31 05:18:33 +00001007 return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr,
1008 AF_INET, cmd.tcpm_key, cmd.tcpm_keylen,
1009 GFP_KERNEL);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001010}
1011
Adam Langley49a72df2008-07-19 00:01:42 -07001012static int tcp_v4_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp,
1013 __be32 daddr, __be32 saddr, int nbytes)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001014{
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001015 struct tcp4_pseudohdr *bp;
Adam Langley49a72df2008-07-19 00:01:42 -07001016 struct scatterlist sg;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001017
1018 bp = &hp->md5_blk.ip4;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001019
1020 /*
Adam Langley49a72df2008-07-19 00:01:42 -07001021 * 1. the TCP pseudo-header (in the order: source IP address,
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001022 * destination IP address, zero-padded protocol number, and
1023 * segment length)
1024 */
1025 bp->saddr = saddr;
1026 bp->daddr = daddr;
1027 bp->pad = 0;
YOSHIFUJI Hideaki076fb722008-04-17 12:48:12 +09001028 bp->protocol = IPPROTO_TCP;
Adam Langley49a72df2008-07-19 00:01:42 -07001029 bp->len = cpu_to_be16(nbytes);
David S. Millerc7da57a2007-10-26 00:41:21 -07001030
Adam Langley49a72df2008-07-19 00:01:42 -07001031 sg_init_one(&sg, bp, sizeof(*bp));
1032 return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp));
1033}
1034
Eric Dumazeta915da9b2012-01-31 05:18:33 +00001035static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key,
Eric Dumazet318cf7a2011-10-24 02:46:04 -04001036 __be32 daddr, __be32 saddr, const struct tcphdr *th)
Adam Langley49a72df2008-07-19 00:01:42 -07001037{
1038 struct tcp_md5sig_pool *hp;
1039 struct hash_desc *desc;
1040
1041 hp = tcp_get_md5sig_pool();
1042 if (!hp)
1043 goto clear_hash_noput;
1044 desc = &hp->md5_desc;
1045
1046 if (crypto_hash_init(desc))
1047 goto clear_hash;
1048 if (tcp_v4_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2))
1049 goto clear_hash;
1050 if (tcp_md5_hash_header(hp, th))
1051 goto clear_hash;
1052 if (tcp_md5_hash_key(hp, key))
1053 goto clear_hash;
1054 if (crypto_hash_final(desc, md5_hash))
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001055 goto clear_hash;
1056
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001057 tcp_put_md5sig_pool();
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001058 return 0;
Adam Langley49a72df2008-07-19 00:01:42 -07001059
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001060clear_hash:
1061 tcp_put_md5sig_pool();
1062clear_hash_noput:
1063 memset(md5_hash, 0, 16);
Adam Langley49a72df2008-07-19 00:01:42 -07001064 return 1;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001065}
1066
Eric Dumazet39f8e582015-03-24 15:58:55 -07001067int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key,
1068 const struct sock *sk,
Eric Dumazet318cf7a2011-10-24 02:46:04 -04001069 const struct sk_buff *skb)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001070{
Adam Langley49a72df2008-07-19 00:01:42 -07001071 struct tcp_md5sig_pool *hp;
1072 struct hash_desc *desc;
Eric Dumazet318cf7a2011-10-24 02:46:04 -04001073 const struct tcphdr *th = tcp_hdr(skb);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001074 __be32 saddr, daddr;
1075
Eric Dumazet39f8e582015-03-24 15:58:55 -07001076 if (sk) { /* valid for establish/request sockets */
1077 saddr = sk->sk_rcv_saddr;
1078 daddr = sk->sk_daddr;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001079 } else {
Adam Langley49a72df2008-07-19 00:01:42 -07001080 const struct iphdr *iph = ip_hdr(skb);
1081 saddr = iph->saddr;
1082 daddr = iph->daddr;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001083 }
Adam Langley49a72df2008-07-19 00:01:42 -07001084
1085 hp = tcp_get_md5sig_pool();
1086 if (!hp)
1087 goto clear_hash_noput;
1088 desc = &hp->md5_desc;
1089
1090 if (crypto_hash_init(desc))
1091 goto clear_hash;
1092
1093 if (tcp_v4_md5_hash_pseudoheader(hp, daddr, saddr, skb->len))
1094 goto clear_hash;
1095 if (tcp_md5_hash_header(hp, th))
1096 goto clear_hash;
1097 if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2))
1098 goto clear_hash;
1099 if (tcp_md5_hash_key(hp, key))
1100 goto clear_hash;
1101 if (crypto_hash_final(desc, md5_hash))
1102 goto clear_hash;
1103
1104 tcp_put_md5sig_pool();
1105 return 0;
1106
1107clear_hash:
1108 tcp_put_md5sig_pool();
1109clear_hash_noput:
1110 memset(md5_hash, 0, 16);
1111 return 1;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001112}
Adam Langley49a72df2008-07-19 00:01:42 -07001113EXPORT_SYMBOL(tcp_v4_md5_hash_skb);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001114
Eric Dumazetff74e232015-03-24 15:58:54 -07001115/* Called with rcu_read_lock() */
1116static bool tcp_v4_inbound_md5_hash(struct sock *sk,
1117 const struct sk_buff *skb)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001118{
1119 /*
1120 * This gets called for each TCP segment that arrives
1121 * so we want to be efficient.
1122 * We have 3 drop cases:
1123 * o No MD5 hash and one expected.
1124 * o MD5 hash and we're not expecting one.
1125 * o MD5 hash and its wrong.
1126 */
Eric Dumazetcf533ea2011-10-21 05:22:42 -04001127 const __u8 *hash_location = NULL;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001128 struct tcp_md5sig_key *hash_expected;
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07001129 const struct iphdr *iph = ip_hdr(skb);
Eric Dumazetcf533ea2011-10-21 05:22:42 -04001130 const struct tcphdr *th = tcp_hdr(skb);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001131 int genhash;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001132 unsigned char newhash[16];
1133
Eric Dumazeta915da9b2012-01-31 05:18:33 +00001134 hash_expected = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&iph->saddr,
1135 AF_INET);
YOSHIFUJI Hideaki7d5d5522008-04-17 12:29:53 +09001136 hash_location = tcp_parse_md5sig_option(th);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001137
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001138 /* We've parsed the options - do we have a hash? */
1139 if (!hash_expected && !hash_location)
Eric Dumazeta2a385d2012-05-16 23:15:34 +00001140 return false;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001141
1142 if (hash_expected && !hash_location) {
David S. Miller785957d2008-07-30 03:03:15 -07001143 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
Eric Dumazeta2a385d2012-05-16 23:15:34 +00001144 return true;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001145 }
1146
1147 if (!hash_expected && hash_location) {
David S. Miller785957d2008-07-30 03:03:15 -07001148 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
Eric Dumazeta2a385d2012-05-16 23:15:34 +00001149 return true;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001150 }
1151
1152 /* Okay, so this is hash_expected and hash_location -
1153 * so we need to calculate the checksum.
1154 */
Adam Langley49a72df2008-07-19 00:01:42 -07001155 genhash = tcp_v4_md5_hash_skb(newhash,
1156 hash_expected,
Eric Dumazet39f8e582015-03-24 15:58:55 -07001157 NULL, skb);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001158
1159 if (genhash || memcmp(hash_location, newhash, 16) != 0) {
Joe Perchese87cc472012-05-13 21:56:26 +00001160 net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s\n",
1161 &iph->saddr, ntohs(th->source),
1162 &iph->daddr, ntohs(th->dest),
1163 genhash ? " tcp_v4_calc_md5_hash failed"
1164 : "");
Eric Dumazeta2a385d2012-05-16 23:15:34 +00001165 return true;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001166 }
Eric Dumazeta2a385d2012-05-16 23:15:34 +00001167 return false;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001168}
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001169#endif
1170
Eric Dumazet08d2cc3b2015-03-18 14:05:38 -07001171static void tcp_v4_init_req(struct request_sock *req, struct sock *sk_listener,
Octavian Purdila16bea702014-06-25 17:09:53 +03001172 struct sk_buff *skb)
1173{
1174 struct inet_request_sock *ireq = inet_rsk(req);
1175
Eric Dumazet08d2cc3b2015-03-18 14:05:38 -07001176 sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr);
1177 sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr);
1178 ireq->no_srccheck = inet_sk(sk_listener)->transparent;
Octavian Purdila16bea702014-06-25 17:09:53 +03001179 ireq->opt = tcp_v4_save_options(skb);
1180}
1181
Octavian Purdilad94e0412014-06-25 17:09:55 +03001182static struct dst_entry *tcp_v4_route_req(struct sock *sk, struct flowi *fl,
1183 const struct request_sock *req,
1184 bool *strict)
1185{
1186 struct dst_entry *dst = inet_csk_route_req(sk, &fl->u.ip4, req);
1187
1188 if (strict) {
1189 if (fl->u.ip4.daddr == inet_rsk(req)->ir_rmt_addr)
1190 *strict = true;
1191 else
1192 *strict = false;
1193 }
1194
1195 return dst;
1196}
1197
Eric Dumazet72a3eff2006-11-16 02:30:37 -08001198struct request_sock_ops tcp_request_sock_ops __read_mostly = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001199 .family = PF_INET,
Arnaldo Carvalho de Melo2e6599c2005-06-18 22:46:52 -07001200 .obj_size = sizeof(struct tcp_request_sock),
Octavian Purdila5db92c92014-06-25 17:09:59 +03001201 .rtx_syn_ack = tcp_rtx_synack,
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -07001202 .send_ack = tcp_v4_reqsk_send_ack,
1203 .destructor = tcp_v4_reqsk_destructor,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001204 .send_reset = tcp_v4_send_reset,
stephen hemminger688d1942014-08-29 23:32:05 -07001205 .syn_ack_timeout = tcp_syn_ack_timeout,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001206};
1207
Stephen Hemmingerb2e4b3d2009-09-01 19:25:03 +00001208static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = {
Octavian Purdila2aec4a22014-06-25 17:10:00 +03001209 .mss_clamp = TCP_MSS_DEFAULT,
Octavian Purdila16bea702014-06-25 17:09:53 +03001210#ifdef CONFIG_TCP_MD5SIG
Eric Dumazetfd3a1542015-03-24 15:58:56 -07001211 .req_md5_lookup = tcp_v4_md5_lookup,
John Dykstrae3afe7b2009-07-16 05:04:51 +00001212 .calc_md5_hash = tcp_v4_md5_hash_skb,
Andrew Mortonb6332e62006-11-30 19:16:28 -08001213#endif
Octavian Purdila16bea702014-06-25 17:09:53 +03001214 .init_req = tcp_v4_init_req,
Octavian Purdilafb7b37a2014-06-25 17:09:54 +03001215#ifdef CONFIG_SYN_COOKIES
1216 .cookie_init_seq = cookie_v4_init_sequence,
1217#endif
Octavian Purdilad94e0412014-06-25 17:09:55 +03001218 .route_req = tcp_v4_route_req,
Octavian Purdila936b8bd2014-06-25 17:09:57 +03001219 .init_seq = tcp_v4_init_sequence,
Octavian Purdilad6274bd2014-06-25 17:09:58 +03001220 .send_synack = tcp_v4_send_synack,
Octavian Purdila695da142014-06-25 17:10:01 +03001221 .queue_hash_add = inet_csk_reqsk_queue_hash_add,
Octavian Purdila16bea702014-06-25 17:09:53 +03001222};
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001223
Linus Torvalds1da177e2005-04-16 15:20:36 -07001224int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
1225{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001226 /* Never answer to SYNs send to broadcast or multicast */
Eric Dumazet511c3f92009-06-02 05:14:27 +00001227 if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001228 goto drop;
1229
Octavian Purdila1fb6f152014-06-25 17:10:02 +03001230 return tcp_conn_request(&tcp_request_sock_ops,
1231 &tcp_request_sock_ipv4_ops, sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001232
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233drop:
Vijay Subramanian848bf152013-01-31 08:24:06 +00001234 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001235 return 0;
1236}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00001237EXPORT_SYMBOL(tcp_v4_conn_request);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238
1239
1240/*
1241 * The three way handshake has completed - we got a valid synack -
1242 * now create the new socket.
1243 */
1244struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -07001245 struct request_sock *req,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001246 struct dst_entry *dst)
1247{
Arnaldo Carvalho de Melo2e6599c2005-06-18 22:46:52 -07001248 struct inet_request_sock *ireq;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001249 struct inet_sock *newinet;
1250 struct tcp_sock *newtp;
1251 struct sock *newsk;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001252#ifdef CONFIG_TCP_MD5SIG
1253 struct tcp_md5sig_key *key;
1254#endif
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001255 struct ip_options_rcu *inet_opt;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001256
1257 if (sk_acceptq_is_full(sk))
1258 goto exit_overflow;
1259
Linus Torvalds1da177e2005-04-16 15:20:36 -07001260 newsk = tcp_create_openreq_child(sk, req, skb);
1261 if (!newsk)
Balazs Scheidler093d2822010-10-21 13:06:43 +02001262 goto exit_nonewsk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263
Herbert Xubcd76112006-06-30 13:36:35 -07001264 newsk->sk_gso_type = SKB_GSO_TCPV4;
Neal Cardwellfae6ef82012-08-19 03:30:38 +00001265 inet_sk_rx_dst_set(newsk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001266
1267 newtp = tcp_sk(newsk);
1268 newinet = inet_sk(newsk);
Arnaldo Carvalho de Melo2e6599c2005-06-18 22:46:52 -07001269 ireq = inet_rsk(req);
Eric Dumazetd1e559d2015-03-18 14:05:35 -07001270 sk_daddr_set(newsk, ireq->ir_rmt_addr);
1271 sk_rcv_saddr_set(newsk, ireq->ir_loc_addr);
Eric Dumazet634fb9792013-10-09 15:21:29 -07001272 newinet->inet_saddr = ireq->ir_loc_addr;
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001273 inet_opt = ireq->opt;
1274 rcu_assign_pointer(newinet->inet_opt, inet_opt);
Arnaldo Carvalho de Melo2e6599c2005-06-18 22:46:52 -07001275 ireq->opt = NULL;
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001276 newinet->mc_index = inet_iif(skb);
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07001277 newinet->mc_ttl = ip_hdr(skb)->ttl;
Jiri Benc4c507d22012-02-09 09:35:49 +00001278 newinet->rcv_tos = ip_hdr(skb)->tos;
Arnaldo Carvalho de Melod83d8462005-12-13 23:26:10 -08001279 inet_csk(newsk)->icsk_ext_hdr_len = 0;
Tom Herbertb73c3d02014-07-01 21:32:17 -07001280 inet_set_txhash(newsk);
Eric Dumazetf6d8bd02011-04-21 09:45:37 +00001281 if (inet_opt)
1282 inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen;
Eric Dumazetc720c7e2009-10-15 06:30:45 +00001283 newinet->inet_id = newtp->write_seq ^ jiffies;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001284
Eric Dumazetdfd25ff2012-03-10 09:20:21 +00001285 if (!dst) {
1286 dst = inet_csk_route_child_sock(sk, newsk, req);
1287 if (!dst)
1288 goto put_and_exit;
1289 } else {
1290 /* syncookie case : see end of cookie_v4_check() */
1291 }
David S. Miller0e734412011-05-08 15:28:03 -07001292 sk_setup_caps(newsk, dst);
1293
Daniel Borkmann81164412015-01-05 23:57:48 +01001294 tcp_ca_openreq_child(newsk, dst);
1295
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296 tcp_sync_mss(newsk, dst_mtu(dst));
David S. Miller0dbaee32010-12-13 12:52:14 -08001297 newtp->advmss = dst_metric_advmss(dst);
Tom Quetchenbachf5fff5d2008-09-21 00:21:51 -07001298 if (tcp_sk(sk)->rx_opt.user_mss &&
1299 tcp_sk(sk)->rx_opt.user_mss < newtp->advmss)
1300 newtp->advmss = tcp_sk(sk)->rx_opt.user_mss;
1301
Linus Torvalds1da177e2005-04-16 15:20:36 -07001302 tcp_initialize_rcv_mss(newsk);
1303
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001304#ifdef CONFIG_TCP_MD5SIG
1305 /* Copy over the MD5 key from the original socket */
Eric Dumazeta915da9b2012-01-31 05:18:33 +00001306 key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&newinet->inet_daddr,
1307 AF_INET);
Ian Morris00db4122015-04-03 09:17:27 +01001308 if (key) {
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001309 /*
1310 * We're using one, so create a matching key
1311 * on the newsk structure. If we fail to get
1312 * memory, then we end up not copying the key
1313 * across. Shucks.
1314 */
Eric Dumazeta915da9b2012-01-31 05:18:33 +00001315 tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newinet->inet_daddr,
1316 AF_INET, key->key, key->keylen, GFP_ATOMIC);
Eric Dumazeta4654192010-05-16 00:36:33 -07001317 sk_nocaps_add(newsk, NETIF_F_GSO_MASK);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001318 }
1319#endif
1320
David S. Miller0e734412011-05-08 15:28:03 -07001321 if (__inet_inherit_port(sk, newsk) < 0)
1322 goto put_and_exit;
Eric Dumazet9327f702009-12-04 03:46:54 +00001323 __inet_hash_nolisten(newsk, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001324
1325 return newsk;
1326
1327exit_overflow:
Pavel Emelyanovde0744a2008-07-16 20:31:16 -07001328 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
Balazs Scheidler093d2822010-10-21 13:06:43 +02001329exit_nonewsk:
1330 dst_release(dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331exit:
Pavel Emelyanovde0744a2008-07-16 20:31:16 -07001332 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001333 return NULL;
David S. Miller0e734412011-05-08 15:28:03 -07001334put_and_exit:
Christoph Paasche337e242012-12-14 04:07:58 +00001335 inet_csk_prepare_forced_close(newsk);
1336 tcp_done(newsk);
David S. Miller0e734412011-05-08 15:28:03 -07001337 goto exit;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001338}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00001339EXPORT_SYMBOL(tcp_v4_syn_recv_sock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001340
1341static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb)
1342{
Eric Dumazet52452c52015-03-19 19:04:19 -07001343 const struct tcphdr *th = tcp_hdr(skb);
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07001344 const struct iphdr *iph = ip_hdr(skb);
Eric Dumazet52452c52015-03-19 19:04:19 -07001345 struct request_sock *req;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346 struct sock *nsk;
Eric Dumazet52452c52015-03-19 19:04:19 -07001347
1348 req = inet_csk_search_req(sk, th->source, iph->saddr, iph->daddr);
Eric Dumazetfa76ce732015-03-19 19:04:20 -07001349 if (req) {
1350 nsk = tcp_check_req(sk, skb, req, false);
1351 reqsk_put(req);
1352 return nsk;
1353 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001354
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +09001355 nsk = inet_lookup_established(sock_net(sk), &tcp_hashinfo, iph->saddr,
Pavel Emelyanovc67499c2008-01-31 05:06:40 -08001356 th->source, iph->daddr, th->dest, inet_iif(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001357
1358 if (nsk) {
1359 if (nsk->sk_state != TCP_TIME_WAIT) {
1360 bh_lock_sock(nsk);
1361 return nsk;
1362 }
YOSHIFUJI Hideaki9469c7b2006-10-10 19:41:46 -07001363 inet_twsk_put(inet_twsk(nsk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001364 return NULL;
1365 }
1366
1367#ifdef CONFIG_SYN_COOKIES
Florian Westphalaf9b4732010-06-03 00:43:44 +00001368 if (!th->syn)
Cong Wang461b74c2014-10-15 14:33:22 -07001369 sk = cookie_v4_check(sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370#endif
1371 return sk;
1372}
1373
Linus Torvalds1da177e2005-04-16 15:20:36 -07001374/* The socket must have it's spinlock held when we get
1375 * here.
1376 *
1377 * We have a potential double-lock case here, so even when
1378 * doing backlog processing we use the BH locking scheme.
1379 * This is because we cannot sleep with the original spinlock
1380 * held.
1381 */
1382int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
1383{
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001384 struct sock *rsk;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001385
Linus Torvalds1da177e2005-04-16 15:20:36 -07001386 if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
Eric Dumazet404e0a82012-07-29 23:20:37 +00001387 struct dst_entry *dst = sk->sk_rx_dst;
1388
Tom Herbertbdeab992011-08-14 19:45:55 +00001389 sock_rps_save_rxhash(sk, skb);
Eric Dumazet3d973792014-11-11 05:54:27 -08001390 sk_mark_napi_id(sk, skb);
Eric Dumazet404e0a82012-07-29 23:20:37 +00001391 if (dst) {
Eric Dumazet505fbcf2012-07-27 06:23:40 +00001392 if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif ||
Ian Morris51456b22015-04-03 09:17:26 +01001393 !dst->ops->check(dst, 0)) {
David S. Miller92101b32012-07-23 16:29:00 -07001394 dst_release(dst);
1395 sk->sk_rx_dst = NULL;
1396 }
1397 }
Vijay Subramanianc995ae22013-09-03 12:23:22 -07001398 tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001399 return 0;
1400 }
1401
Arnaldo Carvalho de Meloab6a5bb2007-03-18 17:43:48 -07001402 if (skb->len < tcp_hdrlen(skb) || tcp_checksum_complete(skb))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001403 goto csum_err;
1404
1405 if (sk->sk_state == TCP_LISTEN) {
1406 struct sock *nsk = tcp_v4_hnd_req(sk, skb);
1407 if (!nsk)
1408 goto discard;
1409
1410 if (nsk != sk) {
Tom Herbertbdeab992011-08-14 19:45:55 +00001411 sock_rps_save_rxhash(nsk, skb);
Eric Dumazet3d973792014-11-11 05:54:27 -08001412 sk_mark_napi_id(sk, skb);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001413 if (tcp_child_process(sk, nsk, skb)) {
1414 rsk = nsk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001415 goto reset;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001416 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417 return 0;
1418 }
Eric Dumazetca551582010-06-03 09:03:58 +00001419 } else
Tom Herbertbdeab992011-08-14 19:45:55 +00001420 sock_rps_save_rxhash(sk, skb);
Eric Dumazetca551582010-06-03 09:03:58 +00001421
Arnaldo Carvalho de Meloaa8223c2007-04-10 21:04:22 -07001422 if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len)) {
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001423 rsk = sk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001424 goto reset;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001425 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001426 return 0;
1427
1428reset:
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001429 tcp_v4_send_reset(rsk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001430discard:
1431 kfree_skb(skb);
1432 /* Be careful here. If this function gets more complicated and
1433 * gcc suffers from register pressure on the x86, sk (in %ebx)
1434 * might be destroyed here. This current version compiles correctly,
1435 * but you have been warned.
1436 */
1437 return 0;
1438
1439csum_err:
Eric Dumazet6a5dc9e2013-04-29 08:39:56 +00001440 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_CSUMERRORS);
Pavel Emelyanov63231bd2008-07-16 20:22:25 -07001441 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001442 goto discard;
1443}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00001444EXPORT_SYMBOL(tcp_v4_do_rcv);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001445
David S. Miller160eb5a2012-06-27 22:01:22 -07001446void tcp_v4_early_demux(struct sk_buff *skb)
David S. Miller41063e92012-06-19 21:22:05 -07001447{
David S. Miller41063e92012-06-19 21:22:05 -07001448 const struct iphdr *iph;
1449 const struct tcphdr *th;
1450 struct sock *sk;
David S. Miller41063e92012-06-19 21:22:05 -07001451
David S. Miller41063e92012-06-19 21:22:05 -07001452 if (skb->pkt_type != PACKET_HOST)
David S. Miller160eb5a2012-06-27 22:01:22 -07001453 return;
David S. Miller41063e92012-06-19 21:22:05 -07001454
Eric Dumazet45f00f92012-10-22 21:42:47 +00001455 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr)))
David S. Miller160eb5a2012-06-27 22:01:22 -07001456 return;
David S. Miller41063e92012-06-19 21:22:05 -07001457
1458 iph = ip_hdr(skb);
Eric Dumazet45f00f92012-10-22 21:42:47 +00001459 th = tcp_hdr(skb);
David S. Miller41063e92012-06-19 21:22:05 -07001460
1461 if (th->doff < sizeof(struct tcphdr) / 4)
David S. Miller160eb5a2012-06-27 22:01:22 -07001462 return;
David S. Miller41063e92012-06-19 21:22:05 -07001463
Eric Dumazet45f00f92012-10-22 21:42:47 +00001464 sk = __inet_lookup_established(dev_net(skb->dev), &tcp_hashinfo,
David S. Miller41063e92012-06-19 21:22:05 -07001465 iph->saddr, th->source,
Vijay Subramanian7011d082012-06-23 17:38:10 +00001466 iph->daddr, ntohs(th->dest),
Eric Dumazet9cb429d2012-07-24 01:19:31 +00001467 skb->skb_iif);
David S. Miller41063e92012-06-19 21:22:05 -07001468 if (sk) {
1469 skb->sk = sk;
1470 skb->destructor = sock_edemux;
Eric Dumazetf7e4eb02015-03-15 21:12:13 -07001471 if (sk_fullsock(sk)) {
Michal Kubečekd0c294c2015-03-23 15:14:00 +01001472 struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst);
Eric Dumazet505fbcf2012-07-27 06:23:40 +00001473
David S. Miller41063e92012-06-19 21:22:05 -07001474 if (dst)
1475 dst = dst_check(dst, 0);
David S. Miller92101b32012-07-23 16:29:00 -07001476 if (dst &&
Eric Dumazet505fbcf2012-07-27 06:23:40 +00001477 inet_sk(sk)->rx_dst_ifindex == skb->skb_iif)
David S. Miller92101b32012-07-23 16:29:00 -07001478 skb_dst_set_noref(skb, dst);
David S. Miller41063e92012-06-19 21:22:05 -07001479 }
1480 }
David S. Miller41063e92012-06-19 21:22:05 -07001481}
1482
Eric Dumazetb2fb4f52013-03-06 12:58:01 +00001483/* Packet is added to VJ-style prequeue for processing in process
1484 * context, if a reader task is waiting. Apparently, this exciting
1485 * idea (VJ's mail "Re: query about TCP header on tcp-ip" of 07 Sep 93)
1486 * failed somewhere. Latency? Burstiness? Well, at least now we will
1487 * see, why it failed. 8)8) --ANK
1488 *
1489 */
1490bool tcp_prequeue(struct sock *sk, struct sk_buff *skb)
1491{
1492 struct tcp_sock *tp = tcp_sk(sk);
1493
1494 if (sysctl_tcp_low_latency || !tp->ucopy.task)
1495 return false;
1496
1497 if (skb->len <= tcp_hdrlen(skb) &&
1498 skb_queue_len(&tp->ucopy.prequeue) == 0)
1499 return false;
1500
Eric Dumazetca777ef2014-09-08 08:06:07 -07001501 /* Before escaping RCU protected region, we need to take care of skb
1502 * dst. Prequeue is only enabled for established sockets.
1503 * For such sockets, we might need the skb dst only to set sk->sk_rx_dst
1504 * Instead of doing full sk_rx_dst validity here, let's perform
1505 * an optimistic check.
1506 */
1507 if (likely(sk->sk_rx_dst))
1508 skb_dst_drop(skb);
1509 else
1510 skb_dst_force(skb);
1511
Eric Dumazetb2fb4f52013-03-06 12:58:01 +00001512 __skb_queue_tail(&tp->ucopy.prequeue, skb);
1513 tp->ucopy.memory += skb->truesize;
1514 if (tp->ucopy.memory > sk->sk_rcvbuf) {
1515 struct sk_buff *skb1;
1516
1517 BUG_ON(sock_owned_by_user(sk));
1518
1519 while ((skb1 = __skb_dequeue(&tp->ucopy.prequeue)) != NULL) {
1520 sk_backlog_rcv(sk, skb1);
1521 NET_INC_STATS_BH(sock_net(sk),
1522 LINUX_MIB_TCPPREQUEUEDROPPED);
1523 }
1524
1525 tp->ucopy.memory = 0;
1526 } else if (skb_queue_len(&tp->ucopy.prequeue) == 1) {
1527 wake_up_interruptible_sync_poll(sk_sleep(sk),
1528 POLLIN | POLLRDNORM | POLLRDBAND);
1529 if (!inet_csk_ack_scheduled(sk))
1530 inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
1531 (3 * tcp_rto_min(sk)) / 4,
1532 TCP_RTO_MAX);
1533 }
1534 return true;
1535}
1536EXPORT_SYMBOL(tcp_prequeue);
1537
Linus Torvalds1da177e2005-04-16 15:20:36 -07001538/*
1539 * From tcp_input.c
1540 */
1541
1542int tcp_v4_rcv(struct sk_buff *skb)
1543{
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07001544 const struct iphdr *iph;
Eric Dumazetcf533ea2011-10-21 05:22:42 -04001545 const struct tcphdr *th;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001546 struct sock *sk;
1547 int ret;
Pavel Emelyanova86b1e32008-07-16 20:20:58 -07001548 struct net *net = dev_net(skb->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001549
1550 if (skb->pkt_type != PACKET_HOST)
1551 goto discard_it;
1552
1553 /* Count it even if it's bad */
Pavel Emelyanov63231bd2008-07-16 20:22:25 -07001554 TCP_INC_STATS_BH(net, TCP_MIB_INSEGS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001555
1556 if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
1557 goto discard_it;
1558
Arnaldo Carvalho de Meloaa8223c2007-04-10 21:04:22 -07001559 th = tcp_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001560
1561 if (th->doff < sizeof(struct tcphdr) / 4)
1562 goto bad_packet;
1563 if (!pskb_may_pull(skb, th->doff * 4))
1564 goto discard_it;
1565
1566 /* An explanation is required here, I think.
1567 * Packet length and doff are validated by header prediction,
Stephen Hemmingercaa20d9a2005-11-10 17:13:47 -08001568 * provided case of th->doff==0 is eliminated.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001569 * So, we defer the checks. */
Tom Herberted70fcf2014-05-02 16:29:38 -07001570
1571 if (skb_checksum_init(skb, IPPROTO_TCP, inet_compute_pseudo))
Eric Dumazet6a5dc9e2013-04-29 08:39:56 +00001572 goto csum_error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573
Arnaldo Carvalho de Meloaa8223c2007-04-10 21:04:22 -07001574 th = tcp_hdr(skb);
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07001575 iph = ip_hdr(skb);
Eric Dumazet971f10e2014-09-27 09:50:57 -07001576 /* This is tricky : We move IPCB at its correct location into TCP_SKB_CB()
1577 * barrier() makes sure compiler wont play fool^Waliasing games.
1578 */
1579 memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb),
1580 sizeof(struct inet_skb_parm));
1581 barrier();
1582
Linus Torvalds1da177e2005-04-16 15:20:36 -07001583 TCP_SKB_CB(skb)->seq = ntohl(th->seq);
1584 TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
1585 skb->len - th->doff * 4);
1586 TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
Eric Dumazete11ecdd2014-09-15 04:19:51 -07001587 TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th);
Eric Dumazet04317da2014-09-05 15:33:32 -07001588 TCP_SKB_CB(skb)->tcp_tw_isn = 0;
Eric Dumazetb82d1bb2011-09-27 02:20:08 -04001589 TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001590 TCP_SKB_CB(skb)->sacked = 0;
1591
Arnaldo Carvalho de Melo9a1f27c2008-10-07 11:41:57 -07001592 sk = __inet_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593 if (!sk)
1594 goto no_tcp_socket;
1595
Eric Dumazetbb134d52010-03-09 05:55:56 +00001596process:
1597 if (sk->sk_state == TCP_TIME_WAIT)
1598 goto do_time_wait;
1599
Eric Dumazet6cce09f2010-03-07 23:21:57 +00001600 if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) {
1601 NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
Stephen Hemmingerd218d112010-01-11 16:28:01 -08001602 goto discard_and_relse;
Eric Dumazet6cce09f2010-03-07 23:21:57 +00001603 }
Stephen Hemmingerd218d112010-01-11 16:28:01 -08001604
Linus Torvalds1da177e2005-04-16 15:20:36 -07001605 if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
1606 goto discard_and_relse;
Dmitry Popov9ea88a12014-08-07 02:38:22 +04001607
1608#ifdef CONFIG_TCP_MD5SIG
1609 /*
1610 * We really want to reject the packet as early as possible
1611 * if:
1612 * o We're expecting an MD5'd packet and this is no MD5 tcp option
1613 * o There is an MD5 option and we're not expecting one
1614 */
1615 if (tcp_v4_inbound_md5_hash(sk, skb))
1616 goto discard_and_relse;
1617#endif
1618
Patrick McHardyb59c2702006-01-06 23:06:10 -08001619 nf_reset(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620
Dmitry Mishinfda9ef52006-08-31 15:28:39 -07001621 if (sk_filter(sk, skb))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001622 goto discard_and_relse;
1623
Eric Dumazet2c8c56e2014-11-11 05:54:28 -08001624 sk_incoming_cpu_update(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001625 skb->dev = NULL;
1626
Ingo Molnarc6366182006-07-03 00:25:13 -07001627 bh_lock_sock_nested(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001628 ret = 0;
1629 if (!sock_owned_by_user(sk)) {
Dan Williams7bced392013-12-30 12:37:29 -08001630 if (!tcp_prequeue(sk, skb))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001631 ret = tcp_v4_do_rcv(sk, skb);
Eric Dumazetda882c12012-04-22 23:38:54 +00001632 } else if (unlikely(sk_add_backlog(sk, skb,
1633 sk->sk_rcvbuf + sk->sk_sndbuf))) {
Zhu Yi6b03a532010-03-04 18:01:41 +00001634 bh_unlock_sock(sk);
Eric Dumazet6cce09f2010-03-07 23:21:57 +00001635 NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP);
Zhu Yi6b03a532010-03-04 18:01:41 +00001636 goto discard_and_relse;
1637 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001638 bh_unlock_sock(sk);
1639
1640 sock_put(sk);
1641
1642 return ret;
1643
1644no_tcp_socket:
1645 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
1646 goto discard_it;
1647
1648 if (skb->len < (th->doff << 2) || tcp_checksum_complete(skb)) {
Eric Dumazet6a5dc9e2013-04-29 08:39:56 +00001649csum_error:
1650 TCP_INC_STATS_BH(net, TCP_MIB_CSUMERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651bad_packet:
Pavel Emelyanov63231bd2008-07-16 20:22:25 -07001652 TCP_INC_STATS_BH(net, TCP_MIB_INERRS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653 } else {
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001654 tcp_v4_send_reset(NULL, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001655 }
1656
1657discard_it:
1658 /* Discard frame. */
1659 kfree_skb(skb);
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001660 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001661
1662discard_and_relse:
1663 sock_put(sk);
1664 goto discard_it;
1665
1666do_time_wait:
1667 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
YOSHIFUJI Hideaki9469c7b2006-10-10 19:41:46 -07001668 inet_twsk_put(inet_twsk(sk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669 goto discard_it;
1670 }
1671
Eric Dumazet6a5dc9e2013-04-29 08:39:56 +00001672 if (skb->len < (th->doff << 2)) {
YOSHIFUJI Hideaki9469c7b2006-10-10 19:41:46 -07001673 inet_twsk_put(inet_twsk(sk));
Eric Dumazet6a5dc9e2013-04-29 08:39:56 +00001674 goto bad_packet;
1675 }
1676 if (tcp_checksum_complete(skb)) {
1677 inet_twsk_put(inet_twsk(sk));
1678 goto csum_error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001679 }
YOSHIFUJI Hideaki9469c7b2006-10-10 19:41:46 -07001680 switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001681 case TCP_TW_SYN: {
YOSHIFUJI Hideakic346dca2008-03-25 21:47:49 +09001682 struct sock *sk2 = inet_lookup_listener(dev_net(skb->dev),
Pavel Emelyanovc67499c2008-01-31 05:06:40 -08001683 &tcp_hashinfo,
Tom Herbertda5e3632013-01-22 09:50:24 +00001684 iph->saddr, th->source,
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07001685 iph->daddr, th->dest,
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001686 inet_iif(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001687 if (sk2) {
Eric Dumazet789f5582015-04-12 18:51:09 -07001688 inet_twsk_deschedule(inet_twsk(sk));
YOSHIFUJI Hideaki9469c7b2006-10-10 19:41:46 -07001689 inet_twsk_put(inet_twsk(sk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001690 sk = sk2;
1691 goto process;
1692 }
1693 /* Fall through to ACK */
1694 }
1695 case TCP_TW_ACK:
1696 tcp_v4_timewait_ack(sk, skb);
1697 break;
1698 case TCP_TW_RST:
1699 goto no_tcp_socket;
1700 case TCP_TW_SUCCESS:;
1701 }
1702 goto discard_it;
1703}
1704
David S. Millerccb7c412010-12-01 18:09:13 -08001705static struct timewait_sock_ops tcp_timewait_sock_ops = {
1706 .twsk_obj_size = sizeof(struct tcp_timewait_sock),
1707 .twsk_unique = tcp_twsk_unique,
1708 .twsk_destructor= tcp_twsk_destructor,
David S. Millerccb7c412010-12-01 18:09:13 -08001709};
Linus Torvalds1da177e2005-04-16 15:20:36 -07001710
Eric Dumazet63d02d12012-08-09 14:11:00 +00001711void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb)
Eric Dumazet5d299f32012-08-06 05:09:33 +00001712{
1713 struct dst_entry *dst = skb_dst(skb);
1714
Eric Dumazetca777ef2014-09-08 08:06:07 -07001715 if (dst) {
1716 dst_hold(dst);
1717 sk->sk_rx_dst = dst;
1718 inet_sk(sk)->rx_dst_ifindex = skb->skb_iif;
1719 }
Eric Dumazet5d299f32012-08-06 05:09:33 +00001720}
Eric Dumazet63d02d12012-08-09 14:11:00 +00001721EXPORT_SYMBOL(inet_sk_rx_dst_set);
Eric Dumazet5d299f32012-08-06 05:09:33 +00001722
Stephen Hemminger3b401a82009-09-01 19:25:04 +00001723const struct inet_connection_sock_af_ops ipv4_specific = {
Arnaldo Carvalho de Melo543d9cf2006-03-20 22:48:35 -08001724 .queue_xmit = ip_queue_xmit,
1725 .send_check = tcp_v4_send_check,
1726 .rebuild_header = inet_sk_rebuild_header,
Eric Dumazet5d299f32012-08-06 05:09:33 +00001727 .sk_rx_dst_set = inet_sk_rx_dst_set,
Arnaldo Carvalho de Melo543d9cf2006-03-20 22:48:35 -08001728 .conn_request = tcp_v4_conn_request,
1729 .syn_recv_sock = tcp_v4_syn_recv_sock,
Arnaldo Carvalho de Melo543d9cf2006-03-20 22:48:35 -08001730 .net_header_len = sizeof(struct iphdr),
1731 .setsockopt = ip_setsockopt,
1732 .getsockopt = ip_getsockopt,
1733 .addr2sockaddr = inet_csk_addr2sockaddr,
1734 .sockaddr_len = sizeof(struct sockaddr_in),
Arnaldo Carvalho de Meloab1e0a12008-02-03 04:06:04 -08001735 .bind_conflict = inet_csk_bind_conflict,
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08001736#ifdef CONFIG_COMPAT
Arnaldo Carvalho de Melo543d9cf2006-03-20 22:48:35 -08001737 .compat_setsockopt = compat_ip_setsockopt,
1738 .compat_getsockopt = compat_ip_getsockopt,
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08001739#endif
Neal Cardwell4fab9072014-08-14 12:40:05 -04001740 .mtu_reduced = tcp_v4_mtu_reduced,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001741};
Eric Dumazet4bc2f182010-07-09 21:22:10 +00001742EXPORT_SYMBOL(ipv4_specific);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001743
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001744#ifdef CONFIG_TCP_MD5SIG
Stephen Hemmingerb2e4b3d2009-09-01 19:25:03 +00001745static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = {
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001746 .md5_lookup = tcp_v4_md5_lookup,
Adam Langley49a72df2008-07-19 00:01:42 -07001747 .calc_md5_hash = tcp_v4_md5_hash_skb,
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001748 .md5_parse = tcp_v4_parse_md5_keys,
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001749};
Andrew Mortonb6332e62006-11-30 19:16:28 -08001750#endif
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001751
Linus Torvalds1da177e2005-04-16 15:20:36 -07001752/* NOTE: A lot of things set to zero explicitly by call to
1753 * sk_alloc() so need not be done here.
1754 */
1755static int tcp_v4_init_sock(struct sock *sk)
1756{
Arnaldo Carvalho de Melo6687e982005-08-10 04:03:31 -03001757 struct inet_connection_sock *icsk = inet_csk(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001758
Neal Cardwell900f65d2012-04-19 09:55:21 +00001759 tcp_init_sock(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001760
Arnaldo Carvalho de Melo8292a172005-12-13 23:15:52 -08001761 icsk->icsk_af_ops = &ipv4_specific;
Neal Cardwell900f65d2012-04-19 09:55:21 +00001762
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001763#ifdef CONFIG_TCP_MD5SIG
David S. Millerac807fa2012-04-23 03:21:58 -04001764 tcp_sk(sk)->af_specific = &tcp_sock_ipv4_specific;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001765#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001766
Linus Torvalds1da177e2005-04-16 15:20:36 -07001767 return 0;
1768}
1769
Brian Haley7d06b2e2008-06-14 17:04:49 -07001770void tcp_v4_destroy_sock(struct sock *sk)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001771{
1772 struct tcp_sock *tp = tcp_sk(sk);
1773
1774 tcp_clear_xmit_timers(sk);
1775
Arnaldo Carvalho de Melo6687e982005-08-10 04:03:31 -03001776 tcp_cleanup_congestion_control(sk);
Stephen Hemminger317a76f2005-06-23 12:19:55 -07001777
Linus Torvalds1da177e2005-04-16 15:20:36 -07001778 /* Cleanup up the write buffer. */
David S. Millerfe067e82007-03-07 12:12:44 -08001779 tcp_write_queue_purge(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001780
1781 /* Cleans up our, hopefully empty, out_of_order_queue. */
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001782 __skb_queue_purge(&tp->out_of_order_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001783
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001784#ifdef CONFIG_TCP_MD5SIG
1785 /* Clean up the MD5 key list, if any */
1786 if (tp->md5sig_info) {
Eric Dumazeta915da9b2012-01-31 05:18:33 +00001787 tcp_clear_md5_list(sk);
Eric Dumazeta8afca02012-01-31 18:45:40 +00001788 kfree_rcu(tp->md5sig_info, rcu);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08001789 tp->md5sig_info = NULL;
1790 }
1791#endif
1792
Linus Torvalds1da177e2005-04-16 15:20:36 -07001793 /* Clean prequeue, it must be empty really */
1794 __skb_queue_purge(&tp->ucopy.prequeue);
1795
1796 /* Clean up a referenced TCP bind bucket. */
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001797 if (inet_csk(sk)->icsk_bind_hash)
Arnaldo Carvalho de Meloab1e0a12008-02-03 04:06:04 -08001798 inet_put_port(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001799
Ian Morris00db4122015-04-03 09:17:27 +01001800 BUG_ON(tp->fastopen_rsk);
William Allen Simpson435cf552009-12-02 18:17:05 +00001801
Yuchung Chengcf60af02012-07-19 06:43:09 +00001802 /* If socket is aborted during connect operation */
1803 tcp_free_fastopen_req(tp);
1804
Glauber Costa180d8cd2011-12-11 21:47:02 +00001805 sk_sockets_allocated_dec(sk);
Glauber Costad1a4c0b2011-12-11 21:47:04 +00001806 sock_release_memcg(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001807}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001808EXPORT_SYMBOL(tcp_v4_destroy_sock);
1809
1810#ifdef CONFIG_PROC_FS
1811/* Proc filesystem TCP sock list dumping. */
1812
Tom Herberta8b690f2010-06-07 00:43:42 -07001813/*
1814 * Get next listener socket follow cur. If cur is NULL, get first socket
1815 * starting from bucket given in st->bucket; when st->bucket is zero the
1816 * very first socket in the hash table is returned.
1817 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001818static void *listening_get_next(struct seq_file *seq, void *cur)
1819{
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001820 struct inet_connection_sock *icsk;
Eric Dumazetc25eb3b2008-11-23 17:22:55 -08001821 struct hlist_nulls_node *node;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001822 struct sock *sk = cur;
Eric Dumazet5caea4e2008-11-20 00:40:07 -08001823 struct inet_listen_hashbucket *ilb;
Jianjun Kong5799de02008-11-03 02:49:10 -08001824 struct tcp_iter_state *st = seq->private;
Denis V. Luneva4146b12008-04-13 22:11:14 -07001825 struct net *net = seq_file_net(seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001826
1827 if (!sk) {
Tom Herberta8b690f2010-06-07 00:43:42 -07001828 ilb = &tcp_hashinfo.listening_hash[st->bucket];
Eric Dumazet5caea4e2008-11-20 00:40:07 -08001829 spin_lock_bh(&ilb->lock);
Eric Dumazetc25eb3b2008-11-23 17:22:55 -08001830 sk = sk_nulls_head(&ilb->head);
Tom Herberta8b690f2010-06-07 00:43:42 -07001831 st->offset = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001832 goto get_sk;
1833 }
Eric Dumazet5caea4e2008-11-20 00:40:07 -08001834 ilb = &tcp_hashinfo.listening_hash[st->bucket];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001835 ++st->num;
Tom Herberta8b690f2010-06-07 00:43:42 -07001836 ++st->offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001837
1838 if (st->state == TCP_SEQ_STATE_OPENREQ) {
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -07001839 struct request_sock *req = cur;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001840
Eric Dumazet72a3eff2006-11-16 02:30:37 -08001841 icsk = inet_csk(st->syn_wait_sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001842 req = req->dl_next;
1843 while (1) {
1844 while (req) {
Daniel Lezcanobdccc4c2008-07-19 00:15:13 -07001845 if (req->rsk_ops->family == st->family) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001846 cur = req;
1847 goto out;
1848 }
1849 req = req->dl_next;
1850 }
Eric Dumazet72a3eff2006-11-16 02:30:37 -08001851 if (++st->sbucket >= icsk->icsk_accept_queue.listen_opt->nr_table_entries)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001852 break;
1853get_req:
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001854 req = icsk->icsk_accept_queue.listen_opt->syn_table[st->sbucket];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001855 }
Eric Dumazet1bde5ac2010-12-23 09:32:46 -08001856 sk = sk_nulls_next(st->syn_wait_sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001857 st->state = TCP_SEQ_STATE_LISTENING;
Eric Dumazetb2827052015-03-22 10:22:21 -07001858 spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001859 } else {
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001860 icsk = inet_csk(sk);
Eric Dumazetb2827052015-03-22 10:22:21 -07001861 spin_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001862 if (reqsk_queue_len(&icsk->icsk_accept_queue))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001863 goto start_req;
Eric Dumazetb2827052015-03-22 10:22:21 -07001864 spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
Eric Dumazet1bde5ac2010-12-23 09:32:46 -08001865 sk = sk_nulls_next(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001866 }
1867get_sk:
Eric Dumazetc25eb3b2008-11-23 17:22:55 -08001868 sk_nulls_for_each_from(sk, node) {
Pavel Emelyanov8475ef92010-11-22 03:26:12 +00001869 if (!net_eq(sock_net(sk), net))
1870 continue;
1871 if (sk->sk_family == st->family) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001872 cur = sk;
1873 goto out;
1874 }
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001875 icsk = inet_csk(sk);
Eric Dumazetb2827052015-03-22 10:22:21 -07001876 spin_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001877 if (reqsk_queue_len(&icsk->icsk_accept_queue)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001878start_req:
1879 st->uid = sock_i_uid(sk);
1880 st->syn_wait_sk = sk;
1881 st->state = TCP_SEQ_STATE_OPENREQ;
1882 st->sbucket = 0;
1883 goto get_req;
1884 }
Eric Dumazetb2827052015-03-22 10:22:21 -07001885 spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001886 }
Eric Dumazet5caea4e2008-11-20 00:40:07 -08001887 spin_unlock_bh(&ilb->lock);
Tom Herberta8b690f2010-06-07 00:43:42 -07001888 st->offset = 0;
Arnaldo Carvalho de Melo0f7ff922005-08-09 19:59:44 -07001889 if (++st->bucket < INET_LHTABLE_SIZE) {
Eric Dumazet5caea4e2008-11-20 00:40:07 -08001890 ilb = &tcp_hashinfo.listening_hash[st->bucket];
1891 spin_lock_bh(&ilb->lock);
Eric Dumazetc25eb3b2008-11-23 17:22:55 -08001892 sk = sk_nulls_head(&ilb->head);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001893 goto get_sk;
1894 }
1895 cur = NULL;
1896out:
1897 return cur;
1898}
1899
1900static void *listening_get_idx(struct seq_file *seq, loff_t *pos)
1901{
Tom Herberta8b690f2010-06-07 00:43:42 -07001902 struct tcp_iter_state *st = seq->private;
1903 void *rc;
1904
1905 st->bucket = 0;
1906 st->offset = 0;
1907 rc = listening_get_next(seq, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001908
1909 while (rc && *pos) {
1910 rc = listening_get_next(seq, rc);
1911 --*pos;
1912 }
1913 return rc;
1914}
1915
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07001916static inline bool empty_bucket(const struct tcp_iter_state *st)
Andi Kleen6eac5602008-08-28 01:08:02 -07001917{
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07001918 return hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].chain);
Andi Kleen6eac5602008-08-28 01:08:02 -07001919}
1920
Tom Herberta8b690f2010-06-07 00:43:42 -07001921/*
1922 * Get first established socket starting from bucket given in st->bucket.
1923 * If st->bucket is zero, the very first socket in the hash is returned.
1924 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001925static void *established_get_first(struct seq_file *seq)
1926{
Jianjun Kong5799de02008-11-03 02:49:10 -08001927 struct tcp_iter_state *st = seq->private;
Denis V. Luneva4146b12008-04-13 22:11:14 -07001928 struct net *net = seq_file_net(seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001929 void *rc = NULL;
1930
Tom Herberta8b690f2010-06-07 00:43:42 -07001931 st->offset = 0;
1932 for (; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001933 struct sock *sk;
Eric Dumazet3ab5aee2008-11-16 19:40:17 -08001934 struct hlist_nulls_node *node;
Eric Dumazet9db66bd2008-11-20 20:39:09 -08001935 spinlock_t *lock = inet_ehash_lockp(&tcp_hashinfo, st->bucket);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001936
Andi Kleen6eac5602008-08-28 01:08:02 -07001937 /* Lockless fast path for the common case of empty buckets */
1938 if (empty_bucket(st))
1939 continue;
1940
Eric Dumazet9db66bd2008-11-20 20:39:09 -08001941 spin_lock_bh(lock);
Eric Dumazet3ab5aee2008-11-16 19:40:17 -08001942 sk_nulls_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) {
Daniel Lezcanof40c8172008-03-21 04:13:54 -07001943 if (sk->sk_family != st->family ||
YOSHIFUJI Hideaki878628f2008-03-26 03:57:35 +09001944 !net_eq(sock_net(sk), net)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001945 continue;
1946 }
1947 rc = sk;
1948 goto out;
1949 }
Eric Dumazet9db66bd2008-11-20 20:39:09 -08001950 spin_unlock_bh(lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001951 }
1952out:
1953 return rc;
1954}
1955
1956static void *established_get_next(struct seq_file *seq, void *cur)
1957{
1958 struct sock *sk = cur;
Eric Dumazet3ab5aee2008-11-16 19:40:17 -08001959 struct hlist_nulls_node *node;
Jianjun Kong5799de02008-11-03 02:49:10 -08001960 struct tcp_iter_state *st = seq->private;
Denis V. Luneva4146b12008-04-13 22:11:14 -07001961 struct net *net = seq_file_net(seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001962
1963 ++st->num;
Tom Herberta8b690f2010-06-07 00:43:42 -07001964 ++st->offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001965
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07001966 sk = sk_nulls_next(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001967
Eric Dumazet3ab5aee2008-11-16 19:40:17 -08001968 sk_nulls_for_each_from(sk, node) {
YOSHIFUJI Hideaki878628f2008-03-26 03:57:35 +09001969 if (sk->sk_family == st->family && net_eq(sock_net(sk), net))
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07001970 return sk;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001971 }
1972
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07001973 spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket));
1974 ++st->bucket;
1975 return established_get_first(seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001976}
1977
1978static void *established_get_idx(struct seq_file *seq, loff_t pos)
1979{
Tom Herberta8b690f2010-06-07 00:43:42 -07001980 struct tcp_iter_state *st = seq->private;
1981 void *rc;
1982
1983 st->bucket = 0;
1984 rc = established_get_first(seq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001985
1986 while (rc && pos) {
1987 rc = established_get_next(seq, rc);
1988 --pos;
Arnaldo Carvalho de Melo71742592006-11-17 10:57:30 -02001989 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001990 return rc;
1991}
1992
1993static void *tcp_get_idx(struct seq_file *seq, loff_t pos)
1994{
1995 void *rc;
Jianjun Kong5799de02008-11-03 02:49:10 -08001996 struct tcp_iter_state *st = seq->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001997
Linus Torvalds1da177e2005-04-16 15:20:36 -07001998 st->state = TCP_SEQ_STATE_LISTENING;
1999 rc = listening_get_idx(seq, &pos);
2000
2001 if (!rc) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002002 st->state = TCP_SEQ_STATE_ESTABLISHED;
2003 rc = established_get_idx(seq, pos);
2004 }
2005
2006 return rc;
2007}
2008
Tom Herberta8b690f2010-06-07 00:43:42 -07002009static void *tcp_seek_last_pos(struct seq_file *seq)
2010{
2011 struct tcp_iter_state *st = seq->private;
2012 int offset = st->offset;
2013 int orig_num = st->num;
2014 void *rc = NULL;
2015
2016 switch (st->state) {
2017 case TCP_SEQ_STATE_OPENREQ:
2018 case TCP_SEQ_STATE_LISTENING:
2019 if (st->bucket >= INET_LHTABLE_SIZE)
2020 break;
2021 st->state = TCP_SEQ_STATE_LISTENING;
2022 rc = listening_get_next(seq, NULL);
2023 while (offset-- && rc)
2024 rc = listening_get_next(seq, rc);
2025 if (rc)
2026 break;
2027 st->bucket = 0;
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07002028 st->state = TCP_SEQ_STATE_ESTABLISHED;
Tom Herberta8b690f2010-06-07 00:43:42 -07002029 /* Fallthrough */
2030 case TCP_SEQ_STATE_ESTABLISHED:
Tom Herberta8b690f2010-06-07 00:43:42 -07002031 if (st->bucket > tcp_hashinfo.ehash_mask)
2032 break;
2033 rc = established_get_first(seq);
2034 while (offset-- && rc)
2035 rc = established_get_next(seq, rc);
2036 }
2037
2038 st->num = orig_num;
2039
2040 return rc;
2041}
2042
Linus Torvalds1da177e2005-04-16 15:20:36 -07002043static void *tcp_seq_start(struct seq_file *seq, loff_t *pos)
2044{
Jianjun Kong5799de02008-11-03 02:49:10 -08002045 struct tcp_iter_state *st = seq->private;
Tom Herberta8b690f2010-06-07 00:43:42 -07002046 void *rc;
2047
2048 if (*pos && *pos == st->last_pos) {
2049 rc = tcp_seek_last_pos(seq);
2050 if (rc)
2051 goto out;
2052 }
2053
Linus Torvalds1da177e2005-04-16 15:20:36 -07002054 st->state = TCP_SEQ_STATE_LISTENING;
2055 st->num = 0;
Tom Herberta8b690f2010-06-07 00:43:42 -07002056 st->bucket = 0;
2057 st->offset = 0;
2058 rc = *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2059
2060out:
2061 st->last_pos = *pos;
2062 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002063}
2064
2065static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2066{
Tom Herberta8b690f2010-06-07 00:43:42 -07002067 struct tcp_iter_state *st = seq->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002068 void *rc = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002069
2070 if (v == SEQ_START_TOKEN) {
2071 rc = tcp_get_idx(seq, 0);
2072 goto out;
2073 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002074
2075 switch (st->state) {
2076 case TCP_SEQ_STATE_OPENREQ:
2077 case TCP_SEQ_STATE_LISTENING:
2078 rc = listening_get_next(seq, v);
2079 if (!rc) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002080 st->state = TCP_SEQ_STATE_ESTABLISHED;
Tom Herberta8b690f2010-06-07 00:43:42 -07002081 st->bucket = 0;
2082 st->offset = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002083 rc = established_get_first(seq);
2084 }
2085 break;
2086 case TCP_SEQ_STATE_ESTABLISHED:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002087 rc = established_get_next(seq, v);
2088 break;
2089 }
2090out:
2091 ++*pos;
Tom Herberta8b690f2010-06-07 00:43:42 -07002092 st->last_pos = *pos;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002093 return rc;
2094}
2095
2096static void tcp_seq_stop(struct seq_file *seq, void *v)
2097{
Jianjun Kong5799de02008-11-03 02:49:10 -08002098 struct tcp_iter_state *st = seq->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002099
2100 switch (st->state) {
2101 case TCP_SEQ_STATE_OPENREQ:
2102 if (v) {
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002103 struct inet_connection_sock *icsk = inet_csk(st->syn_wait_sk);
Eric Dumazetb2827052015-03-22 10:22:21 -07002104 spin_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002105 }
2106 case TCP_SEQ_STATE_LISTENING:
2107 if (v != SEQ_START_TOKEN)
Eric Dumazet5caea4e2008-11-20 00:40:07 -08002108 spin_unlock_bh(&tcp_hashinfo.listening_hash[st->bucket].lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002109 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002110 case TCP_SEQ_STATE_ESTABLISHED:
2111 if (v)
Eric Dumazet9db66bd2008-11-20 20:39:09 -08002112 spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002113 break;
2114 }
2115}
2116
Arjan van de Ven73cb88e2011-10-30 06:46:30 +00002117int tcp_seq_open(struct inode *inode, struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002118{
Al Virod9dda782013-03-31 18:16:14 -04002119 struct tcp_seq_afinfo *afinfo = PDE_DATA(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002120 struct tcp_iter_state *s;
Denis V. Lunev52d6f3f2008-04-13 22:12:41 -07002121 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002122
Denis V. Lunev52d6f3f2008-04-13 22:12:41 -07002123 err = seq_open_net(inode, file, &afinfo->seq_ops,
2124 sizeof(struct tcp_iter_state));
2125 if (err < 0)
2126 return err;
Daniel Lezcanof40c8172008-03-21 04:13:54 -07002127
Denis V. Lunev52d6f3f2008-04-13 22:12:41 -07002128 s = ((struct seq_file *)file->private_data)->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002129 s->family = afinfo->family;
stephen hemminger688d1942014-08-29 23:32:05 -07002130 s->last_pos = 0;
Daniel Lezcanof40c8172008-03-21 04:13:54 -07002131 return 0;
2132}
Arjan van de Ven73cb88e2011-10-30 06:46:30 +00002133EXPORT_SYMBOL(tcp_seq_open);
Daniel Lezcanof40c8172008-03-21 04:13:54 -07002134
Daniel Lezcano6f8b13b2008-03-21 04:14:45 -07002135int tcp_proc_register(struct net *net, struct tcp_seq_afinfo *afinfo)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002136{
2137 int rc = 0;
2138 struct proc_dir_entry *p;
2139
Denis V. Lunev9427c4b2008-04-13 22:12:13 -07002140 afinfo->seq_ops.start = tcp_seq_start;
2141 afinfo->seq_ops.next = tcp_seq_next;
2142 afinfo->seq_ops.stop = tcp_seq_stop;
2143
Denis V. Lunev84841c32008-05-02 04:10:08 -07002144 p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
Arjan van de Ven73cb88e2011-10-30 06:46:30 +00002145 afinfo->seq_fops, afinfo);
Denis V. Lunev84841c32008-05-02 04:10:08 -07002146 if (!p)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002147 rc = -ENOMEM;
2148 return rc;
2149}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00002150EXPORT_SYMBOL(tcp_proc_register);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002151
Daniel Lezcano6f8b13b2008-03-21 04:14:45 -07002152void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002153{
Gao fengece31ff2013-02-18 01:34:56 +00002154 remove_proc_entry(afinfo->name, net->proc_net);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002155}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00002156EXPORT_SYMBOL(tcp_proc_unregister);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002157
Eric Dumazetd4f06872015-03-12 16:44:09 -07002158static void get_openreq4(const struct request_sock *req,
Tetsuo Handa652586d2013-11-14 14:31:57 -08002159 struct seq_file *f, int i, kuid_t uid)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002160{
Arnaldo Carvalho de Melo2e6599c2005-06-18 22:46:52 -07002161 const struct inet_request_sock *ireq = inet_rsk(req);
Eric Dumazetfa76ce732015-03-19 19:04:20 -07002162 long delta = req->rsk_timer.expires - jiffies;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002163
Pavel Emelyanov5e659e42008-04-24 01:02:16 -07002164 seq_printf(f, "%4d: %08X:%04X %08X:%04X"
Tetsuo Handa652586d2013-11-14 14:31:57 -08002165 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %u %d %pK",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002166 i,
Eric Dumazet634fb9792013-10-09 15:21:29 -07002167 ireq->ir_loc_addr,
Eric Dumazetd4f06872015-03-12 16:44:09 -07002168 ireq->ir_num,
Eric Dumazet634fb9792013-10-09 15:21:29 -07002169 ireq->ir_rmt_addr,
2170 ntohs(ireq->ir_rmt_port),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002171 TCP_SYN_RECV,
2172 0, 0, /* could print option size, but that is af dependent. */
2173 1, /* timers active (only the expire timer) */
Eric Dumazeta399a802012-08-08 21:13:53 +00002174 jiffies_delta_to_clock_t(delta),
Eric Dumazete6c022a2012-10-27 23:16:46 +00002175 req->num_timeout,
Eric W. Biedermana7cb5a42012-05-24 01:10:10 -06002176 from_kuid_munged(seq_user_ns(f), uid),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002177 0, /* non standard timer */
2178 0, /* open_requests have no inode */
Eric Dumazetd4f06872015-03-12 16:44:09 -07002179 0,
Tetsuo Handa652586d2013-11-14 14:31:57 -08002180 req);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002181}
2182
Tetsuo Handa652586d2013-11-14 14:31:57 -08002183static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002184{
2185 int timer_active;
2186 unsigned long timer_expires;
Eric Dumazetcf533ea2011-10-21 05:22:42 -04002187 const struct tcp_sock *tp = tcp_sk(sk);
Ilpo Järvinencf4c6bf2007-02-22 01:13:58 -08002188 const struct inet_connection_sock *icsk = inet_csk(sk);
Eric Dumazetcf533ea2011-10-21 05:22:42 -04002189 const struct inet_sock *inet = inet_sk(sk);
Jerry Chu168a8f52012-08-31 12:29:13 +00002190 struct fastopen_queue *fastopenq = icsk->icsk_accept_queue.fastopenq;
Eric Dumazetc720c7e2009-10-15 06:30:45 +00002191 __be32 dest = inet->inet_daddr;
2192 __be32 src = inet->inet_rcv_saddr;
2193 __u16 destp = ntohs(inet->inet_dport);
2194 __u16 srcp = ntohs(inet->inet_sport);
Eric Dumazet49d09002009-12-03 16:06:13 -08002195 int rx_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002196
Nandita Dukkipati6ba8a3b2013-03-11 10:00:43 +00002197 if (icsk->icsk_pending == ICSK_TIME_RETRANS ||
2198 icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS ||
2199 icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002200 timer_active = 1;
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002201 timer_expires = icsk->icsk_timeout;
2202 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002203 timer_active = 4;
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002204 timer_expires = icsk->icsk_timeout;
Ilpo Järvinencf4c6bf2007-02-22 01:13:58 -08002205 } else if (timer_pending(&sk->sk_timer)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002206 timer_active = 2;
Ilpo Järvinencf4c6bf2007-02-22 01:13:58 -08002207 timer_expires = sk->sk_timer.expires;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002208 } else {
2209 timer_active = 0;
2210 timer_expires = jiffies;
2211 }
2212
Eric Dumazet49d09002009-12-03 16:06:13 -08002213 if (sk->sk_state == TCP_LISTEN)
2214 rx_queue = sk->sk_ack_backlog;
2215 else
2216 /*
2217 * because we dont lock socket, we might find a transient negative value
2218 */
2219 rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0);
2220
Pavel Emelyanov5e659e42008-04-24 01:02:16 -07002221 seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX "
Tetsuo Handa652586d2013-11-14 14:31:57 -08002222 "%08X %5u %8d %lu %d %pK %lu %lu %u %u %d",
Ilpo Järvinencf4c6bf2007-02-22 01:13:58 -08002223 i, src, srcp, dest, destp, sk->sk_state,
Sridhar Samudrala47da8ee2006-06-27 13:29:00 -07002224 tp->write_seq - tp->snd_una,
Eric Dumazet49d09002009-12-03 16:06:13 -08002225 rx_queue,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002226 timer_active,
Eric Dumazeta399a802012-08-08 21:13:53 +00002227 jiffies_delta_to_clock_t(timer_expires - jiffies),
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002228 icsk->icsk_retransmits,
Eric W. Biedermana7cb5a42012-05-24 01:10:10 -06002229 from_kuid_munged(seq_user_ns(f), sock_i_uid(sk)),
Arnaldo Carvalho de Melo6687e982005-08-10 04:03:31 -03002230 icsk->icsk_probes_out,
Ilpo Järvinencf4c6bf2007-02-22 01:13:58 -08002231 sock_i_ino(sk),
2232 atomic_read(&sk->sk_refcnt), sk,
Stephen Hemminger7be87352008-06-27 20:00:19 -07002233 jiffies_to_clock_t(icsk->icsk_rto),
2234 jiffies_to_clock_t(icsk->icsk_ack.ato),
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002235 (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002236 tp->snd_cwnd,
Jerry Chu168a8f52012-08-31 12:29:13 +00002237 sk->sk_state == TCP_LISTEN ?
2238 (fastopenq ? fastopenq->max_qlen : 0) :
Tetsuo Handa652586d2013-11-14 14:31:57 -08002239 (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002240}
2241
Eric Dumazetcf533ea2011-10-21 05:22:42 -04002242static void get_timewait4_sock(const struct inet_timewait_sock *tw,
Tetsuo Handa652586d2013-11-14 14:31:57 -08002243 struct seq_file *f, int i)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002244{
Eric Dumazet789f5582015-04-12 18:51:09 -07002245 long delta = tw->tw_timer.expires - jiffies;
Al Viro23f33c22006-09-27 18:43:50 -07002246 __be32 dest, src;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002247 __u16 destp, srcp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002248
2249 dest = tw->tw_daddr;
2250 src = tw->tw_rcv_saddr;
2251 destp = ntohs(tw->tw_dport);
2252 srcp = ntohs(tw->tw_sport);
2253
Pavel Emelyanov5e659e42008-04-24 01:02:16 -07002254 seq_printf(f, "%4d: %08X:%04X %08X:%04X"
Tetsuo Handa652586d2013-11-14 14:31:57 -08002255 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002256 i, src, srcp, dest, destp, tw->tw_substate, 0, 0,
Eric Dumazeta399a802012-08-08 21:13:53 +00002257 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0,
Tetsuo Handa652586d2013-11-14 14:31:57 -08002258 atomic_read(&tw->tw_refcnt), tw);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002259}
2260
2261#define TMPSZ 150
2262
2263static int tcp4_seq_show(struct seq_file *seq, void *v)
2264{
Jianjun Kong5799de02008-11-03 02:49:10 -08002265 struct tcp_iter_state *st;
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07002266 struct sock *sk = v;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002267
Tetsuo Handa652586d2013-11-14 14:31:57 -08002268 seq_setwidth(seq, TMPSZ - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002269 if (v == SEQ_START_TOKEN) {
Tetsuo Handa652586d2013-11-14 14:31:57 -08002270 seq_puts(seq, " sl local_address rem_address st tx_queue "
Linus Torvalds1da177e2005-04-16 15:20:36 -07002271 "rx_queue tr tm->when retrnsmt uid timeout "
2272 "inode");
2273 goto out;
2274 }
2275 st = seq->private;
2276
2277 switch (st->state) {
2278 case TCP_SEQ_STATE_LISTENING:
2279 case TCP_SEQ_STATE_ESTABLISHED:
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07002280 if (sk->sk_state == TCP_TIME_WAIT)
Tetsuo Handa652586d2013-11-14 14:31:57 -08002281 get_timewait4_sock(v, seq, st->num);
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07002282 else
Tetsuo Handa652586d2013-11-14 14:31:57 -08002283 get_tcp4_sock(v, seq, st->num);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002284 break;
2285 case TCP_SEQ_STATE_OPENREQ:
Eric Dumazetd4f06872015-03-12 16:44:09 -07002286 get_openreq4(v, seq, st->num, st->uid);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002287 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002288 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002289out:
Tetsuo Handa652586d2013-11-14 14:31:57 -08002290 seq_pad(seq, '\n');
Linus Torvalds1da177e2005-04-16 15:20:36 -07002291 return 0;
2292}
2293
Arjan van de Ven73cb88e2011-10-30 06:46:30 +00002294static const struct file_operations tcp_afinfo_seq_fops = {
2295 .owner = THIS_MODULE,
2296 .open = tcp_seq_open,
2297 .read = seq_read,
2298 .llseek = seq_lseek,
2299 .release = seq_release_net
2300};
2301
Linus Torvalds1da177e2005-04-16 15:20:36 -07002302static struct tcp_seq_afinfo tcp4_seq_afinfo = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002303 .name = "tcp",
2304 .family = AF_INET,
Arjan van de Ven73cb88e2011-10-30 06:46:30 +00002305 .seq_fops = &tcp_afinfo_seq_fops,
Denis V. Lunev9427c4b2008-04-13 22:12:13 -07002306 .seq_ops = {
2307 .show = tcp4_seq_show,
2308 },
Linus Torvalds1da177e2005-04-16 15:20:36 -07002309};
2310
Alexey Dobriyan2c8c1e72010-01-17 03:35:32 +00002311static int __net_init tcp4_proc_init_net(struct net *net)
Pavel Emelyanov757764f2008-03-24 14:56:02 -07002312{
2313 return tcp_proc_register(net, &tcp4_seq_afinfo);
2314}
2315
Alexey Dobriyan2c8c1e72010-01-17 03:35:32 +00002316static void __net_exit tcp4_proc_exit_net(struct net *net)
Pavel Emelyanov757764f2008-03-24 14:56:02 -07002317{
2318 tcp_proc_unregister(net, &tcp4_seq_afinfo);
2319}
2320
2321static struct pernet_operations tcp4_net_ops = {
2322 .init = tcp4_proc_init_net,
2323 .exit = tcp4_proc_exit_net,
2324};
2325
Linus Torvalds1da177e2005-04-16 15:20:36 -07002326int __init tcp4_proc_init(void)
2327{
Pavel Emelyanov757764f2008-03-24 14:56:02 -07002328 return register_pernet_subsys(&tcp4_net_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002329}
2330
2331void tcp4_proc_exit(void)
2332{
Pavel Emelyanov757764f2008-03-24 14:56:02 -07002333 unregister_pernet_subsys(&tcp4_net_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002334}
2335#endif /* CONFIG_PROC_FS */
2336
2337struct proto tcp_prot = {
2338 .name = "TCP",
2339 .owner = THIS_MODULE,
2340 .close = tcp_close,
2341 .connect = tcp_v4_connect,
2342 .disconnect = tcp_disconnect,
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002343 .accept = inet_csk_accept,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002344 .ioctl = tcp_ioctl,
2345 .init = tcp_v4_init_sock,
2346 .destroy = tcp_v4_destroy_sock,
2347 .shutdown = tcp_shutdown,
2348 .setsockopt = tcp_setsockopt,
2349 .getsockopt = tcp_getsockopt,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002350 .recvmsg = tcp_recvmsg,
Changli Gao7ba42912010-07-10 20:41:55 +00002351 .sendmsg = tcp_sendmsg,
2352 .sendpage = tcp_sendpage,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002353 .backlog_rcv = tcp_v4_do_rcv,
Eric Dumazet46d3cea2012-07-11 05:50:31 +00002354 .release_cb = tcp_release_cb,
Arnaldo Carvalho de Meloab1e0a12008-02-03 04:06:04 -08002355 .hash = inet_hash,
2356 .unhash = inet_unhash,
2357 .get_port = inet_csk_get_port,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002358 .enter_memory_pressure = tcp_enter_memory_pressure,
Eric Dumazetc9bee3b72013-07-22 20:27:07 -07002359 .stream_memory_free = tcp_stream_memory_free,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002360 .sockets_allocated = &tcp_sockets_allocated,
Arnaldo Carvalho de Melo0a5578c2005-08-09 20:11:41 -07002361 .orphan_count = &tcp_orphan_count,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002362 .memory_allocated = &tcp_memory_allocated,
2363 .memory_pressure = &tcp_memory_pressure,
Eric W. Biedermana4fe34b2013-10-19 16:25:36 -07002364 .sysctl_mem = sysctl_tcp_mem,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002365 .sysctl_wmem = sysctl_tcp_wmem,
2366 .sysctl_rmem = sysctl_tcp_rmem,
2367 .max_header = MAX_TCP_HEADER,
2368 .obj_size = sizeof(struct tcp_sock),
Eric Dumazet3ab5aee2008-11-16 19:40:17 -08002369 .slab_flags = SLAB_DESTROY_BY_RCU,
Arnaldo Carvalho de Melo6d6ee432005-12-13 23:25:19 -08002370 .twsk_prot = &tcp_timewait_sock_ops,
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -07002371 .rsk_prot = &tcp_request_sock_ops,
Pavel Emelyanov39d8cda2008-03-22 16:50:58 -07002372 .h.hashinfo = &tcp_hashinfo,
Changli Gao7ba42912010-07-10 20:41:55 +00002373 .no_autobind = true,
Arnaldo Carvalho de Melo543d9cf2006-03-20 22:48:35 -08002374#ifdef CONFIG_COMPAT
2375 .compat_setsockopt = compat_tcp_setsockopt,
2376 .compat_getsockopt = compat_tcp_getsockopt,
2377#endif
Andrew Mortonc255a452012-07-31 16:43:02 -07002378#ifdef CONFIG_MEMCG_KMEM
Glauber Costad1a4c0b2011-12-11 21:47:04 +00002379 .init_cgroup = tcp_init_cgroup,
2380 .destroy_cgroup = tcp_destroy_cgroup,
2381 .proto_cgroup = tcp_proto_cgroup,
2382#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002383};
Eric Dumazet4bc2f182010-07-09 21:22:10 +00002384EXPORT_SYMBOL(tcp_prot);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002385
Denis V. Lunev046ee902008-04-03 14:31:33 -07002386static void __net_exit tcp_sk_exit(struct net *net)
2387{
Eric Dumazetbdbbb852015-01-29 21:35:05 -08002388 int cpu;
2389
2390 for_each_possible_cpu(cpu)
2391 inet_ctl_sock_destroy(*per_cpu_ptr(net->ipv4.tcp_sk, cpu));
2392 free_percpu(net->ipv4.tcp_sk);
2393}
2394
2395static int __net_init tcp_sk_init(struct net *net)
2396{
2397 int res, cpu;
2398
2399 net->ipv4.tcp_sk = alloc_percpu(struct sock *);
2400 if (!net->ipv4.tcp_sk)
2401 return -ENOMEM;
2402
2403 for_each_possible_cpu(cpu) {
2404 struct sock *sk;
2405
2406 res = inet_ctl_sock_create(&sk, PF_INET, SOCK_RAW,
2407 IPPROTO_TCP, net);
2408 if (res)
2409 goto fail;
2410 *per_cpu_ptr(net->ipv4.tcp_sk, cpu) = sk;
2411 }
2412 net->ipv4.sysctl_tcp_ecn = 2;
Fan Dub0f9ca52015-02-10 09:53:16 +08002413 net->ipv4.sysctl_tcp_base_mss = TCP_BASE_MSS;
Fan Du6b58e0a2015-03-06 11:18:23 +08002414 net->ipv4.sysctl_tcp_probe_threshold = TCP_PROBE_THRESHOLD;
Fan Du05cbc0d2015-03-06 11:18:24 +08002415 net->ipv4.sysctl_tcp_probe_interval = TCP_PROBE_INTERVAL;
Eric Dumazetbdbbb852015-01-29 21:35:05 -08002416 return 0;
2417
2418fail:
2419 tcp_sk_exit(net);
2420
2421 return res;
Eric W. Biedermanb099ce22009-12-03 02:29:09 +00002422}
2423
2424static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list)
2425{
2426 inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET);
Denis V. Lunev046ee902008-04-03 14:31:33 -07002427}
2428
2429static struct pernet_operations __net_initdata tcp_sk_ops = {
Eric W. Biedermanb099ce22009-12-03 02:29:09 +00002430 .init = tcp_sk_init,
2431 .exit = tcp_sk_exit,
2432 .exit_batch = tcp_sk_exit_batch,
Denis V. Lunev046ee902008-04-03 14:31:33 -07002433};
2434
Denis V. Lunev9b0f9762008-02-29 11:13:15 -08002435void __init tcp_v4_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002436{
Eric Dumazet5caea4e2008-11-20 00:40:07 -08002437 inet_hashinfo_init(&tcp_hashinfo);
Eric W. Biederman6a1b3052009-02-22 00:10:18 -08002438 if (register_pernet_subsys(&tcp_sk_ops))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002439 panic("Failed to create the TCP control socket.\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002440}