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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
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 | * | |
1da177e4 LT |
8 | * 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 | |
60236fdd | 37 | * request_sock handling and moved |
1da177e4 LT |
38 | * most of it into the af independent code. |
39 | * Added tail drop and some other bugfixes. | |
caa20d9a | 40 | * Added new listen semantics. |
1da177e4 LT |
41 | * 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 | ||
afd46503 | 53 | #define pr_fmt(fmt) "TCP: " fmt |
1da177e4 | 54 | |
eb4dea58 | 55 | #include <linux/bottom_half.h> |
1da177e4 LT |
56 | #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> | |
5a0e3ad6 | 64 | #include <linux/slab.h> |
1da177e4 | 65 | |
457c4cbc | 66 | #include <net/net_namespace.h> |
1da177e4 | 67 | #include <net/icmp.h> |
304a1618 | 68 | #include <net/inet_hashtables.h> |
1da177e4 | 69 | #include <net/tcp.h> |
20380731 | 70 | #include <net/transp_v6.h> |
1da177e4 LT |
71 | #include <net/ipv6.h> |
72 | #include <net/inet_common.h> | |
6d6ee43e | 73 | #include <net/timewait_sock.h> |
1da177e4 | 74 | #include <net/xfrm.h> |
6e5714ea | 75 | #include <net/secure_seq.h> |
076bb0c8 | 76 | #include <net/busy_poll.h> |
1da177e4 LT |
77 | |
78 | #include <linux/inet.h> | |
79 | #include <linux/ipv6.h> | |
80 | #include <linux/stddef.h> | |
81 | #include <linux/proc_fs.h> | |
82 | #include <linux/seq_file.h> | |
83 | ||
cf80e0e4 | 84 | #include <crypto/hash.h> |
cfb6eeb4 YH |
85 | #include <linux/scatterlist.h> |
86 | ||
ab32ea5d | 87 | int sysctl_tcp_low_latency __read_mostly; |
1da177e4 | 88 | |
cfb6eeb4 | 89 | #ifdef CONFIG_TCP_MD5SIG |
a915da9b | 90 | static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, |
318cf7aa | 91 | __be32 daddr, __be32 saddr, const struct tcphdr *th); |
cfb6eeb4 YH |
92 | #endif |
93 | ||
5caea4ea | 94 | struct inet_hashinfo tcp_hashinfo; |
4bc2f18b | 95 | EXPORT_SYMBOL(tcp_hashinfo); |
1da177e4 | 96 | |
95a22cae | 97 | static u32 tcp_v4_init_sequence(const struct sk_buff *skb, u32 *tsoff) |
1da177e4 | 98 | { |
eddc9ec5 ACM |
99 | return secure_tcp_sequence_number(ip_hdr(skb)->daddr, |
100 | ip_hdr(skb)->saddr, | |
aa8223c7 | 101 | tcp_hdr(skb)->dest, |
95a22cae | 102 | tcp_hdr(skb)->source, tsoff); |
1da177e4 LT |
103 | } |
104 | ||
6d6ee43e ACM |
105 | int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp) |
106 | { | |
107 | const struct tcp_timewait_sock *tcptw = tcp_twsk(sktw); | |
108 | struct tcp_sock *tp = tcp_sk(sk); | |
109 | ||
110 | /* With PAWS, it is safe from the viewpoint | |
111 | of data integrity. Even without PAWS it is safe provided sequence | |
112 | spaces do not overlap i.e. at data rates <= 80Mbit/sec. | |
113 | ||
114 | Actually, the idea is close to VJ's one, only timestamp cache is | |
115 | held not per host, but per port pair and TW bucket is used as state | |
116 | holder. | |
117 | ||
118 | If TW bucket has been already destroyed we fall back to VJ's scheme | |
119 | and use initial timestamp retrieved from peer table. | |
120 | */ | |
121 | if (tcptw->tw_ts_recent_stamp && | |
56ab6b93 | 122 | (!twp || (sock_net(sk)->ipv4.sysctl_tcp_tw_reuse && |
9d729f72 | 123 | get_seconds() - tcptw->tw_ts_recent_stamp > 1))) { |
6d6ee43e ACM |
124 | tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2; |
125 | if (tp->write_seq == 0) | |
126 | tp->write_seq = 1; | |
127 | tp->rx_opt.ts_recent = tcptw->tw_ts_recent; | |
128 | tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; | |
129 | sock_hold(sktw); | |
130 | return 1; | |
131 | } | |
132 | ||
133 | return 0; | |
134 | } | |
6d6ee43e ACM |
135 | EXPORT_SYMBOL_GPL(tcp_twsk_unique); |
136 | ||
1da177e4 LT |
137 | /* This will initiate an outgoing connection. */ |
138 | int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
139 | { | |
2d7192d6 | 140 | struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
1da177e4 LT |
141 | struct inet_sock *inet = inet_sk(sk); |
142 | struct tcp_sock *tp = tcp_sk(sk); | |
dca8b089 | 143 | __be16 orig_sport, orig_dport; |
bada8adc | 144 | __be32 daddr, nexthop; |
da905bd1 | 145 | struct flowi4 *fl4; |
2d7192d6 | 146 | struct rtable *rt; |
1da177e4 | 147 | int err; |
f6d8bd05 | 148 | struct ip_options_rcu *inet_opt; |
1946e672 | 149 | struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row; |
1da177e4 LT |
150 | |
151 | if (addr_len < sizeof(struct sockaddr_in)) | |
152 | return -EINVAL; | |
153 | ||
154 | if (usin->sin_family != AF_INET) | |
155 | return -EAFNOSUPPORT; | |
156 | ||
157 | nexthop = daddr = usin->sin_addr.s_addr; | |
f6d8bd05 | 158 | inet_opt = rcu_dereference_protected(inet->inet_opt, |
1e1d04e6 | 159 | lockdep_sock_is_held(sk)); |
f6d8bd05 | 160 | if (inet_opt && inet_opt->opt.srr) { |
1da177e4 LT |
161 | if (!daddr) |
162 | return -EINVAL; | |
f6d8bd05 | 163 | nexthop = inet_opt->opt.faddr; |
1da177e4 LT |
164 | } |
165 | ||
dca8b089 DM |
166 | orig_sport = inet->inet_sport; |
167 | orig_dport = usin->sin_port; | |
da905bd1 DM |
168 | fl4 = &inet->cork.fl.u.ip4; |
169 | rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, | |
b23dd4fe DM |
170 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, |
171 | IPPROTO_TCP, | |
0e0d44ab | 172 | orig_sport, orig_dport, sk); |
b23dd4fe DM |
173 | if (IS_ERR(rt)) { |
174 | err = PTR_ERR(rt); | |
175 | if (err == -ENETUNREACH) | |
f1d8cba6 | 176 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); |
b23dd4fe | 177 | return err; |
584bdf8c | 178 | } |
1da177e4 LT |
179 | |
180 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { | |
181 | ip_rt_put(rt); | |
182 | return -ENETUNREACH; | |
183 | } | |
184 | ||
f6d8bd05 | 185 | if (!inet_opt || !inet_opt->opt.srr) |
da905bd1 | 186 | daddr = fl4->daddr; |
1da177e4 | 187 | |
c720c7e8 | 188 | if (!inet->inet_saddr) |
da905bd1 | 189 | inet->inet_saddr = fl4->saddr; |
d1e559d0 | 190 | sk_rcv_saddr_set(sk, inet->inet_saddr); |
1da177e4 | 191 | |
c720c7e8 | 192 | if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) { |
1da177e4 LT |
193 | /* Reset inherited state */ |
194 | tp->rx_opt.ts_recent = 0; | |
195 | tp->rx_opt.ts_recent_stamp = 0; | |
ee995283 PE |
196 | if (likely(!tp->repair)) |
197 | tp->write_seq = 0; | |
1da177e4 LT |
198 | } |
199 | ||
1946e672 | 200 | if (tcp_death_row->sysctl_tw_recycle && |
81166dd6 DM |
201 | !tp->rx_opt.ts_recent_stamp && fl4->daddr == daddr) |
202 | tcp_fetch_timewait_stamp(sk, &rt->dst); | |
1da177e4 | 203 | |
c720c7e8 | 204 | inet->inet_dport = usin->sin_port; |
d1e559d0 | 205 | sk_daddr_set(sk, daddr); |
1da177e4 | 206 | |
d83d8461 | 207 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
208 | if (inet_opt) |
209 | inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
1da177e4 | 210 | |
bee7ca9e | 211 | tp->rx_opt.mss_clamp = TCP_MSS_DEFAULT; |
1da177e4 LT |
212 | |
213 | /* Socket identity is still unknown (sport may be zero). | |
214 | * However we set state to SYN-SENT and not releasing socket | |
215 | * lock select source port, enter ourselves into the hash tables and | |
216 | * complete initialization after this. | |
217 | */ | |
218 | tcp_set_state(sk, TCP_SYN_SENT); | |
1946e672 | 219 | err = inet_hash_connect(tcp_death_row, sk); |
1da177e4 LT |
220 | if (err) |
221 | goto failure; | |
222 | ||
877d1f62 | 223 | sk_set_txhash(sk); |
9e7ceb06 | 224 | |
da905bd1 | 225 | rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, |
b23dd4fe DM |
226 | inet->inet_sport, inet->inet_dport, sk); |
227 | if (IS_ERR(rt)) { | |
228 | err = PTR_ERR(rt); | |
229 | rt = NULL; | |
1da177e4 | 230 | goto failure; |
b23dd4fe | 231 | } |
1da177e4 | 232 | /* OK, now commit destination to socket. */ |
bcd76111 | 233 | sk->sk_gso_type = SKB_GSO_TCPV4; |
d8d1f30b | 234 | sk_setup_caps(sk, &rt->dst); |
19f6d3f3 | 235 | rt = NULL; |
1da177e4 | 236 | |
ee995283 | 237 | if (!tp->write_seq && likely(!tp->repair)) |
c720c7e8 ED |
238 | tp->write_seq = secure_tcp_sequence_number(inet->inet_saddr, |
239 | inet->inet_daddr, | |
240 | inet->inet_sport, | |
95a22cae FW |
241 | usin->sin_port, |
242 | &tp->tsoffset); | |
1da177e4 | 243 | |
c720c7e8 | 244 | inet->inet_id = tp->write_seq ^ jiffies; |
1da177e4 | 245 | |
19f6d3f3 WW |
246 | if (tcp_fastopen_defer_connect(sk, &err)) |
247 | return err; | |
248 | if (err) | |
249 | goto failure; | |
250 | ||
2b916477 | 251 | err = tcp_connect(sk); |
ee995283 | 252 | |
1da177e4 LT |
253 | if (err) |
254 | goto failure; | |
255 | ||
256 | return 0; | |
257 | ||
258 | failure: | |
7174259e ACM |
259 | /* |
260 | * This unhashes the socket and releases the local port, | |
261 | * if necessary. | |
262 | */ | |
1da177e4 LT |
263 | tcp_set_state(sk, TCP_CLOSE); |
264 | ip_rt_put(rt); | |
265 | sk->sk_route_caps = 0; | |
c720c7e8 | 266 | inet->inet_dport = 0; |
1da177e4 LT |
267 | return err; |
268 | } | |
4bc2f18b | 269 | EXPORT_SYMBOL(tcp_v4_connect); |
1da177e4 | 270 | |
1da177e4 | 271 | /* |
563d34d0 ED |
272 | * This routine reacts to ICMP_FRAG_NEEDED mtu indications as defined in RFC1191. |
273 | * It can be called through tcp_release_cb() if socket was owned by user | |
274 | * at the time tcp_v4_err() was called to handle ICMP message. | |
1da177e4 | 275 | */ |
4fab9071 | 276 | void tcp_v4_mtu_reduced(struct sock *sk) |
1da177e4 LT |
277 | { |
278 | struct dst_entry *dst; | |
279 | struct inet_sock *inet = inet_sk(sk); | |
563d34d0 | 280 | u32 mtu = tcp_sk(sk)->mtu_info; |
1da177e4 | 281 | |
80d0a69f DM |
282 | dst = inet_csk_update_pmtu(sk, mtu); |
283 | if (!dst) | |
1da177e4 LT |
284 | return; |
285 | ||
1da177e4 LT |
286 | /* Something is about to be wrong... Remember soft error |
287 | * for the case, if this connection will not able to recover. | |
288 | */ | |
289 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) | |
290 | sk->sk_err_soft = EMSGSIZE; | |
291 | ||
292 | mtu = dst_mtu(dst); | |
293 | ||
294 | if (inet->pmtudisc != IP_PMTUDISC_DONT && | |
482fc609 | 295 | ip_sk_accept_pmtu(sk) && |
d83d8461 | 296 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
1da177e4 LT |
297 | tcp_sync_mss(sk, mtu); |
298 | ||
299 | /* Resend the TCP packet because it's | |
300 | * clear that the old packet has been | |
301 | * dropped. This is the new "fast" path mtu | |
302 | * discovery. | |
303 | */ | |
304 | tcp_simple_retransmit(sk); | |
305 | } /* else let the usual retransmit timer handle it */ | |
306 | } | |
4fab9071 | 307 | EXPORT_SYMBOL(tcp_v4_mtu_reduced); |
1da177e4 | 308 | |
55be7a9c DM |
309 | static void do_redirect(struct sk_buff *skb, struct sock *sk) |
310 | { | |
311 | struct dst_entry *dst = __sk_dst_check(sk, 0); | |
312 | ||
1ed5c48f | 313 | if (dst) |
6700c270 | 314 | dst->ops->redirect(dst, sk, skb); |
55be7a9c DM |
315 | } |
316 | ||
26e37360 ED |
317 | |
318 | /* handle ICMP messages on TCP_NEW_SYN_RECV request sockets */ | |
9cf74903 | 319 | void tcp_req_err(struct sock *sk, u32 seq, bool abort) |
26e37360 ED |
320 | { |
321 | struct request_sock *req = inet_reqsk(sk); | |
322 | struct net *net = sock_net(sk); | |
323 | ||
324 | /* ICMPs are not backlogged, hence we cannot get | |
325 | * an established socket here. | |
326 | */ | |
26e37360 | 327 | if (seq != tcp_rsk(req)->snt_isn) { |
02a1d6e7 | 328 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
9cf74903 | 329 | } else if (abort) { |
26e37360 ED |
330 | /* |
331 | * Still in SYN_RECV, just remove it silently. | |
332 | * There is no good way to pass the error to the newly | |
333 | * created socket, and POSIX does not want network | |
334 | * errors returned from accept(). | |
335 | */ | |
c6973669 | 336 | inet_csk_reqsk_queue_drop(req->rsk_listener, req); |
9caad864 | 337 | tcp_listendrop(req->rsk_listener); |
26e37360 | 338 | } |
ef84d8ce | 339 | reqsk_put(req); |
26e37360 ED |
340 | } |
341 | EXPORT_SYMBOL(tcp_req_err); | |
342 | ||
1da177e4 LT |
343 | /* |
344 | * This routine is called by the ICMP module when it gets some | |
345 | * sort of error condition. If err < 0 then the socket should | |
346 | * be closed and the error returned to the user. If err > 0 | |
347 | * it's just the icmp type << 8 | icmp code. After adjustment | |
348 | * header points to the first 8 bytes of the tcp header. We need | |
349 | * to find the appropriate port. | |
350 | * | |
351 | * The locking strategy used here is very "optimistic". When | |
352 | * someone else accesses the socket the ICMP is just dropped | |
353 | * and for some paths there is no check at all. | |
354 | * A more general error queue to queue errors for later handling | |
355 | * is probably better. | |
356 | * | |
357 | */ | |
358 | ||
4d1a2d9e | 359 | void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) |
1da177e4 | 360 | { |
b71d1d42 | 361 | const struct iphdr *iph = (const struct iphdr *)icmp_skb->data; |
4d1a2d9e | 362 | struct tcphdr *th = (struct tcphdr *)(icmp_skb->data + (iph->ihl << 2)); |
f1ecd5d9 | 363 | struct inet_connection_sock *icsk; |
1da177e4 LT |
364 | struct tcp_sock *tp; |
365 | struct inet_sock *inet; | |
4d1a2d9e DL |
366 | const int type = icmp_hdr(icmp_skb)->type; |
367 | const int code = icmp_hdr(icmp_skb)->code; | |
1da177e4 | 368 | struct sock *sk; |
f1ecd5d9 | 369 | struct sk_buff *skb; |
0a672f74 YC |
370 | struct request_sock *fastopen; |
371 | __u32 seq, snd_una; | |
f1ecd5d9 | 372 | __u32 remaining; |
1da177e4 | 373 | int err; |
4d1a2d9e | 374 | struct net *net = dev_net(icmp_skb->dev); |
1da177e4 | 375 | |
26e37360 ED |
376 | sk = __inet_lookup_established(net, &tcp_hashinfo, iph->daddr, |
377 | th->dest, iph->saddr, ntohs(th->source), | |
378 | inet_iif(icmp_skb)); | |
1da177e4 | 379 | if (!sk) { |
5d3848bc | 380 | __ICMP_INC_STATS(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
381 | return; |
382 | } | |
383 | if (sk->sk_state == TCP_TIME_WAIT) { | |
9469c7b4 | 384 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
385 | return; |
386 | } | |
26e37360 ED |
387 | seq = ntohl(th->seq); |
388 | if (sk->sk_state == TCP_NEW_SYN_RECV) | |
9cf74903 ED |
389 | return tcp_req_err(sk, seq, |
390 | type == ICMP_PARAMETERPROB || | |
391 | type == ICMP_TIME_EXCEEDED || | |
392 | (type == ICMP_DEST_UNREACH && | |
393 | (code == ICMP_NET_UNREACH || | |
394 | code == ICMP_HOST_UNREACH))); | |
1da177e4 LT |
395 | |
396 | bh_lock_sock(sk); | |
397 | /* If too many ICMPs get dropped on busy | |
398 | * servers this needs to be solved differently. | |
563d34d0 ED |
399 | * We do take care of PMTU discovery (RFC1191) special case : |
400 | * we can receive locally generated ICMP messages while socket is held. | |
1da177e4 | 401 | */ |
b74aa930 ED |
402 | if (sock_owned_by_user(sk)) { |
403 | if (!(type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)) | |
02a1d6e7 | 404 | __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); |
b74aa930 | 405 | } |
1da177e4 LT |
406 | if (sk->sk_state == TCP_CLOSE) |
407 | goto out; | |
408 | ||
97e3ecd1 | 409 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
02a1d6e7 | 410 | __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP); |
97e3ecd1 | 411 | goto out; |
412 | } | |
413 | ||
f1ecd5d9 | 414 | icsk = inet_csk(sk); |
1da177e4 | 415 | tp = tcp_sk(sk); |
0a672f74 YC |
416 | /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ |
417 | fastopen = tp->fastopen_rsk; | |
418 | snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; | |
1da177e4 | 419 | if (sk->sk_state != TCP_LISTEN && |
0a672f74 | 420 | !between(seq, snd_una, tp->snd_nxt)) { |
02a1d6e7 | 421 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
1da177e4 LT |
422 | goto out; |
423 | } | |
424 | ||
425 | switch (type) { | |
55be7a9c DM |
426 | case ICMP_REDIRECT: |
427 | do_redirect(icmp_skb, sk); | |
428 | goto out; | |
1da177e4 LT |
429 | case ICMP_SOURCE_QUENCH: |
430 | /* Just silently ignore these. */ | |
431 | goto out; | |
432 | case ICMP_PARAMETERPROB: | |
433 | err = EPROTO; | |
434 | break; | |
435 | case ICMP_DEST_UNREACH: | |
436 | if (code > NR_ICMP_UNREACH) | |
437 | goto out; | |
438 | ||
439 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ | |
0d4f0608 ED |
440 | /* We are not interested in TCP_LISTEN and open_requests |
441 | * (SYN-ACKs send out by Linux are always <576bytes so | |
442 | * they should go through unfragmented). | |
443 | */ | |
444 | if (sk->sk_state == TCP_LISTEN) | |
445 | goto out; | |
446 | ||
563d34d0 | 447 | tp->mtu_info = info; |
144d56e9 | 448 | if (!sock_owned_by_user(sk)) { |
563d34d0 | 449 | tcp_v4_mtu_reduced(sk); |
144d56e9 | 450 | } else { |
7aa5470c | 451 | if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &sk->sk_tsq_flags)) |
144d56e9 ED |
452 | sock_hold(sk); |
453 | } | |
1da177e4 LT |
454 | goto out; |
455 | } | |
456 | ||
457 | err = icmp_err_convert[code].errno; | |
f1ecd5d9 DL |
458 | /* check if icmp_skb allows revert of backoff |
459 | * (see draft-zimmermann-tcp-lcd) */ | |
460 | if (code != ICMP_NET_UNREACH && code != ICMP_HOST_UNREACH) | |
461 | break; | |
462 | if (seq != tp->snd_una || !icsk->icsk_retransmits || | |
0a672f74 | 463 | !icsk->icsk_backoff || fastopen) |
f1ecd5d9 DL |
464 | break; |
465 | ||
8f49c270 DM |
466 | if (sock_owned_by_user(sk)) |
467 | break; | |
468 | ||
f1ecd5d9 | 469 | icsk->icsk_backoff--; |
fcdd1cf4 ED |
470 | icsk->icsk_rto = tp->srtt_us ? __tcp_set_rto(tp) : |
471 | TCP_TIMEOUT_INIT; | |
472 | icsk->icsk_rto = inet_csk_rto_backoff(icsk, TCP_RTO_MAX); | |
f1ecd5d9 DL |
473 | |
474 | skb = tcp_write_queue_head(sk); | |
475 | BUG_ON(!skb); | |
476 | ||
7faee5c0 ED |
477 | remaining = icsk->icsk_rto - |
478 | min(icsk->icsk_rto, | |
479 | tcp_time_stamp - tcp_skb_timestamp(skb)); | |
f1ecd5d9 DL |
480 | |
481 | if (remaining) { | |
482 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, | |
483 | remaining, TCP_RTO_MAX); | |
f1ecd5d9 DL |
484 | } else { |
485 | /* RTO revert clocked out retransmission. | |
486 | * Will retransmit now */ | |
487 | tcp_retransmit_timer(sk); | |
488 | } | |
489 | ||
1da177e4 LT |
490 | break; |
491 | case ICMP_TIME_EXCEEDED: | |
492 | err = EHOSTUNREACH; | |
493 | break; | |
494 | default: | |
495 | goto out; | |
496 | } | |
497 | ||
498 | switch (sk->sk_state) { | |
1da177e4 | 499 | case TCP_SYN_SENT: |
0a672f74 YC |
500 | case TCP_SYN_RECV: |
501 | /* Only in fast or simultaneous open. If a fast open socket is | |
502 | * is already accepted it is treated as a connected one below. | |
503 | */ | |
51456b29 | 504 | if (fastopen && !fastopen->sk) |
0a672f74 YC |
505 | break; |
506 | ||
1da177e4 | 507 | if (!sock_owned_by_user(sk)) { |
1da177e4 LT |
508 | sk->sk_err = err; |
509 | ||
510 | sk->sk_error_report(sk); | |
511 | ||
512 | tcp_done(sk); | |
513 | } else { | |
514 | sk->sk_err_soft = err; | |
515 | } | |
516 | goto out; | |
517 | } | |
518 | ||
519 | /* If we've already connected we will keep trying | |
520 | * until we time out, or the user gives up. | |
521 | * | |
522 | * rfc1122 4.2.3.9 allows to consider as hard errors | |
523 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, | |
524 | * but it is obsoleted by pmtu discovery). | |
525 | * | |
526 | * Note, that in modern internet, where routing is unreliable | |
527 | * and in each dark corner broken firewalls sit, sending random | |
528 | * errors ordered by their masters even this two messages finally lose | |
529 | * their original sense (even Linux sends invalid PORT_UNREACHs) | |
530 | * | |
531 | * Now we are in compliance with RFCs. | |
532 | * --ANK (980905) | |
533 | */ | |
534 | ||
535 | inet = inet_sk(sk); | |
536 | if (!sock_owned_by_user(sk) && inet->recverr) { | |
537 | sk->sk_err = err; | |
538 | sk->sk_error_report(sk); | |
539 | } else { /* Only an error on timeout */ | |
540 | sk->sk_err_soft = err; | |
541 | } | |
542 | ||
543 | out: | |
544 | bh_unlock_sock(sk); | |
545 | sock_put(sk); | |
546 | } | |
547 | ||
28850dc7 | 548 | void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr) |
1da177e4 | 549 | { |
aa8223c7 | 550 | struct tcphdr *th = tcp_hdr(skb); |
1da177e4 | 551 | |
84fa7933 | 552 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
419f9f89 | 553 | th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0); |
663ead3b | 554 | skb->csum_start = skb_transport_header(skb) - skb->head; |
ff1dcadb | 555 | skb->csum_offset = offsetof(struct tcphdr, check); |
1da177e4 | 556 | } else { |
419f9f89 | 557 | th->check = tcp_v4_check(skb->len, saddr, daddr, |
07f0757a | 558 | csum_partial(th, |
1da177e4 LT |
559 | th->doff << 2, |
560 | skb->csum)); | |
561 | } | |
562 | } | |
563 | ||
419f9f89 | 564 | /* This routine computes an IPv4 TCP checksum. */ |
bb296246 | 565 | void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb) |
419f9f89 | 566 | { |
cf533ea5 | 567 | const struct inet_sock *inet = inet_sk(sk); |
419f9f89 HX |
568 | |
569 | __tcp_v4_send_check(skb, inet->inet_saddr, inet->inet_daddr); | |
570 | } | |
4bc2f18b | 571 | EXPORT_SYMBOL(tcp_v4_send_check); |
419f9f89 | 572 | |
1da177e4 LT |
573 | /* |
574 | * This routine will send an RST to the other tcp. | |
575 | * | |
576 | * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.) | |
577 | * for reset. | |
578 | * Answer: if a packet caused RST, it is not for a socket | |
579 | * existing in our system, if it is matched to a socket, | |
580 | * it is just duplicate segment or bug in other side's TCP. | |
581 | * So that we build reply only basing on parameters | |
582 | * arrived with segment. | |
583 | * Exception: precedence violation. We do not implement it in any case. | |
584 | */ | |
585 | ||
a00e7444 | 586 | static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) |
1da177e4 | 587 | { |
cf533ea5 | 588 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
589 | struct { |
590 | struct tcphdr th; | |
591 | #ifdef CONFIG_TCP_MD5SIG | |
714e85be | 592 | __be32 opt[(TCPOLEN_MD5SIG_ALIGNED >> 2)]; |
cfb6eeb4 YH |
593 | #endif |
594 | } rep; | |
1da177e4 | 595 | struct ip_reply_arg arg; |
cfb6eeb4 | 596 | #ifdef CONFIG_TCP_MD5SIG |
e46787f0 | 597 | struct tcp_md5sig_key *key = NULL; |
658ddaaf SL |
598 | const __u8 *hash_location = NULL; |
599 | unsigned char newhash[16]; | |
600 | int genhash; | |
601 | struct sock *sk1 = NULL; | |
cfb6eeb4 | 602 | #endif |
a86b1e30 | 603 | struct net *net; |
1da177e4 LT |
604 | |
605 | /* Never send a reset in response to a reset. */ | |
606 | if (th->rst) | |
607 | return; | |
608 | ||
c3658e8d ED |
609 | /* If sk not NULL, it means we did a successful lookup and incoming |
610 | * route had to be correct. prequeue might have dropped our dst. | |
611 | */ | |
612 | if (!sk && skb_rtable(skb)->rt_type != RTN_LOCAL) | |
1da177e4 LT |
613 | return; |
614 | ||
615 | /* Swap the send and the receive. */ | |
cfb6eeb4 YH |
616 | memset(&rep, 0, sizeof(rep)); |
617 | rep.th.dest = th->source; | |
618 | rep.th.source = th->dest; | |
619 | rep.th.doff = sizeof(struct tcphdr) / 4; | |
620 | rep.th.rst = 1; | |
1da177e4 LT |
621 | |
622 | if (th->ack) { | |
cfb6eeb4 | 623 | rep.th.seq = th->ack_seq; |
1da177e4 | 624 | } else { |
cfb6eeb4 YH |
625 | rep.th.ack = 1; |
626 | rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin + | |
627 | skb->len - (th->doff << 2)); | |
1da177e4 LT |
628 | } |
629 | ||
7174259e | 630 | memset(&arg, 0, sizeof(arg)); |
cfb6eeb4 YH |
631 | arg.iov[0].iov_base = (unsigned char *)&rep; |
632 | arg.iov[0].iov_len = sizeof(rep.th); | |
633 | ||
0f85feae | 634 | net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); |
cfb6eeb4 | 635 | #ifdef CONFIG_TCP_MD5SIG |
3b24d854 | 636 | rcu_read_lock(); |
658ddaaf | 637 | hash_location = tcp_parse_md5sig_option(th); |
271c3b9b | 638 | if (sk && sk_fullsock(sk)) { |
e46787f0 FW |
639 | key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *) |
640 | &ip_hdr(skb)->saddr, AF_INET); | |
641 | } else if (hash_location) { | |
658ddaaf SL |
642 | /* |
643 | * active side is lost. Try to find listening socket through | |
644 | * source port, and then find md5 key through listening socket. | |
645 | * we are not loose security here: | |
646 | * Incoming packet is checked with md5 hash with finding key, | |
647 | * no RST generated if md5 hash doesn't match. | |
648 | */ | |
a583636a CG |
649 | sk1 = __inet_lookup_listener(net, &tcp_hashinfo, NULL, 0, |
650 | ip_hdr(skb)->saddr, | |
da5e3630 | 651 | th->source, ip_hdr(skb)->daddr, |
658ddaaf SL |
652 | ntohs(th->source), inet_iif(skb)); |
653 | /* don't send rst if it can't find key */ | |
654 | if (!sk1) | |
3b24d854 ED |
655 | goto out; |
656 | ||
658ddaaf SL |
657 | key = tcp_md5_do_lookup(sk1, (union tcp_md5_addr *) |
658 | &ip_hdr(skb)->saddr, AF_INET); | |
659 | if (!key) | |
3b24d854 ED |
660 | goto out; |
661 | ||
658ddaaf | 662 | |
39f8e58e | 663 | genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb); |
658ddaaf | 664 | if (genhash || memcmp(hash_location, newhash, 16) != 0) |
3b24d854 ED |
665 | goto out; |
666 | ||
658ddaaf SL |
667 | } |
668 | ||
cfb6eeb4 YH |
669 | if (key) { |
670 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | | |
671 | (TCPOPT_NOP << 16) | | |
672 | (TCPOPT_MD5SIG << 8) | | |
673 | TCPOLEN_MD5SIG); | |
674 | /* Update length and the length the header thinks exists */ | |
675 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
676 | rep.th.doff = arg.iov[0].iov_len / 4; | |
677 | ||
49a72dfb | 678 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[1], |
78e645cb IJ |
679 | key, ip_hdr(skb)->saddr, |
680 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
681 | } |
682 | #endif | |
eddc9ec5 ACM |
683 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
684 | ip_hdr(skb)->saddr, /* XXX */ | |
52cd5750 | 685 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
1da177e4 | 686 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; |
271c3b9b FW |
687 | arg.flags = (sk && inet_sk_transparent(sk)) ? IP_REPLY_ARG_NOSRCCHECK : 0; |
688 | ||
e2446eaa | 689 | /* When socket is gone, all binding information is lost. |
4c675258 AK |
690 | * routing might fail in this case. No choice here, if we choose to force |
691 | * input interface, we will misroute in case of asymmetric route. | |
e2446eaa | 692 | */ |
4c675258 AK |
693 | if (sk) |
694 | arg.bound_dev_if = sk->sk_bound_dev_if; | |
1da177e4 | 695 | |
271c3b9b FW |
696 | BUILD_BUG_ON(offsetof(struct sock, sk_bound_dev_if) != |
697 | offsetof(struct inet_timewait_sock, tw_bound_dev_if)); | |
698 | ||
66b13d99 | 699 | arg.tos = ip_hdr(skb)->tos; |
e2d118a1 | 700 | arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL); |
47dcc20a | 701 | local_bh_disable(); |
bdbbb852 ED |
702 | ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk), |
703 | skb, &TCP_SKB_CB(skb)->header.h4.opt, | |
24a2d43d ED |
704 | ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, |
705 | &arg, arg.iov[0].iov_len); | |
1da177e4 | 706 | |
90bbcc60 ED |
707 | __TCP_INC_STATS(net, TCP_MIB_OUTSEGS); |
708 | __TCP_INC_STATS(net, TCP_MIB_OUTRSTS); | |
47dcc20a | 709 | local_bh_enable(); |
658ddaaf SL |
710 | |
711 | #ifdef CONFIG_TCP_MD5SIG | |
3b24d854 ED |
712 | out: |
713 | rcu_read_unlock(); | |
658ddaaf | 714 | #endif |
1da177e4 LT |
715 | } |
716 | ||
717 | /* The code following below sending ACKs in SYN-RECV and TIME-WAIT states | |
718 | outside socket context is ugly, certainly. What can I do? | |
719 | */ | |
720 | ||
e2d118a1 | 721 | static void tcp_v4_send_ack(const struct sock *sk, |
e62a123b | 722 | struct sk_buff *skb, u32 seq, u32 ack, |
ee684b6f | 723 | u32 win, u32 tsval, u32 tsecr, int oif, |
88ef4a5a | 724 | struct tcp_md5sig_key *key, |
66b13d99 | 725 | int reply_flags, u8 tos) |
1da177e4 | 726 | { |
cf533ea5 | 727 | const struct tcphdr *th = tcp_hdr(skb); |
1da177e4 LT |
728 | struct { |
729 | struct tcphdr th; | |
714e85be | 730 | __be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2) |
cfb6eeb4 | 731 | #ifdef CONFIG_TCP_MD5SIG |
714e85be | 732 | + (TCPOLEN_MD5SIG_ALIGNED >> 2) |
cfb6eeb4 YH |
733 | #endif |
734 | ]; | |
1da177e4 | 735 | } rep; |
e2d118a1 | 736 | struct net *net = sock_net(sk); |
1da177e4 LT |
737 | struct ip_reply_arg arg; |
738 | ||
739 | memset(&rep.th, 0, sizeof(struct tcphdr)); | |
7174259e | 740 | memset(&arg, 0, sizeof(arg)); |
1da177e4 LT |
741 | |
742 | arg.iov[0].iov_base = (unsigned char *)&rep; | |
743 | arg.iov[0].iov_len = sizeof(rep.th); | |
ee684b6f | 744 | if (tsecr) { |
cfb6eeb4 YH |
745 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | |
746 | (TCPOPT_TIMESTAMP << 8) | | |
747 | TCPOLEN_TIMESTAMP); | |
ee684b6f AV |
748 | rep.opt[1] = htonl(tsval); |
749 | rep.opt[2] = htonl(tsecr); | |
cb48cfe8 | 750 | arg.iov[0].iov_len += TCPOLEN_TSTAMP_ALIGNED; |
1da177e4 LT |
751 | } |
752 | ||
753 | /* Swap the send and the receive. */ | |
754 | rep.th.dest = th->source; | |
755 | rep.th.source = th->dest; | |
756 | rep.th.doff = arg.iov[0].iov_len / 4; | |
757 | rep.th.seq = htonl(seq); | |
758 | rep.th.ack_seq = htonl(ack); | |
759 | rep.th.ack = 1; | |
760 | rep.th.window = htons(win); | |
761 | ||
cfb6eeb4 | 762 | #ifdef CONFIG_TCP_MD5SIG |
cfb6eeb4 | 763 | if (key) { |
ee684b6f | 764 | int offset = (tsecr) ? 3 : 0; |
cfb6eeb4 YH |
765 | |
766 | rep.opt[offset++] = htonl((TCPOPT_NOP << 24) | | |
767 | (TCPOPT_NOP << 16) | | |
768 | (TCPOPT_MD5SIG << 8) | | |
769 | TCPOLEN_MD5SIG); | |
770 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
771 | rep.th.doff = arg.iov[0].iov_len/4; | |
772 | ||
49a72dfb | 773 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[offset], |
90b7e112 AL |
774 | key, ip_hdr(skb)->saddr, |
775 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
776 | } |
777 | #endif | |
88ef4a5a | 778 | arg.flags = reply_flags; |
eddc9ec5 ACM |
779 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
780 | ip_hdr(skb)->saddr, /* XXX */ | |
1da177e4 LT |
781 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
782 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; | |
9501f972 YH |
783 | if (oif) |
784 | arg.bound_dev_if = oif; | |
66b13d99 | 785 | arg.tos = tos; |
e2d118a1 | 786 | arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL); |
47dcc20a | 787 | local_bh_disable(); |
bdbbb852 ED |
788 | ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk), |
789 | skb, &TCP_SKB_CB(skb)->header.h4.opt, | |
24a2d43d ED |
790 | ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, |
791 | &arg, arg.iov[0].iov_len); | |
1da177e4 | 792 | |
90bbcc60 | 793 | __TCP_INC_STATS(net, TCP_MIB_OUTSEGS); |
47dcc20a | 794 | local_bh_enable(); |
1da177e4 LT |
795 | } |
796 | ||
797 | static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) | |
798 | { | |
8feaf0c0 | 799 | struct inet_timewait_sock *tw = inet_twsk(sk); |
cfb6eeb4 | 800 | struct tcp_timewait_sock *tcptw = tcp_twsk(sk); |
1da177e4 | 801 | |
e2d118a1 | 802 | tcp_v4_send_ack(sk, skb, |
e62a123b | 803 | tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, |
7174259e | 804 | tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, |
ee684b6f | 805 | tcp_time_stamp + tcptw->tw_ts_offset, |
9501f972 YH |
806 | tcptw->tw_ts_recent, |
807 | tw->tw_bound_dev_if, | |
88ef4a5a | 808 | tcp_twsk_md5_key(tcptw), |
66b13d99 ED |
809 | tw->tw_transparent ? IP_REPLY_ARG_NOSRCCHECK : 0, |
810 | tw->tw_tos | |
9501f972 | 811 | ); |
1da177e4 | 812 | |
8feaf0c0 | 813 | inet_twsk_put(tw); |
1da177e4 LT |
814 | } |
815 | ||
a00e7444 | 816 | static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, |
7174259e | 817 | struct request_sock *req) |
1da177e4 | 818 | { |
168a8f58 JC |
819 | /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV |
820 | * sk->sk_state == TCP_SYN_RECV -> for Fast Open. | |
821 | */ | |
e62a123b ED |
822 | u32 seq = (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : |
823 | tcp_sk(sk)->snd_nxt; | |
824 | ||
20a2b49f ED |
825 | /* RFC 7323 2.3 |
826 | * The window field (SEG.WND) of every outgoing segment, with the | |
827 | * exception of <SYN> segments, MUST be right-shifted by | |
828 | * Rcv.Wind.Shift bits: | |
829 | */ | |
e2d118a1 | 830 | tcp_v4_send_ack(sk, skb, seq, |
20a2b49f ED |
831 | tcp_rsk(req)->rcv_nxt, |
832 | req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, | |
95a22cae | 833 | tcp_time_stamp + tcp_rsk(req)->ts_off, |
9501f972 YH |
834 | req->ts_recent, |
835 | 0, | |
a915da9b ED |
836 | tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->daddr, |
837 | AF_INET), | |
66b13d99 ED |
838 | inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0, |
839 | ip_hdr(skb)->tos); | |
1da177e4 LT |
840 | } |
841 | ||
1da177e4 | 842 | /* |
9bf1d83e | 843 | * Send a SYN-ACK after having received a SYN. |
60236fdd | 844 | * This still operates on a request_sock only, not on a big |
1da177e4 LT |
845 | * socket. |
846 | */ | |
0f935dbe | 847 | static int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst, |
d6274bd8 | 848 | struct flowi *fl, |
72659ecc | 849 | struct request_sock *req, |
ca6fb065 | 850 | struct tcp_fastopen_cookie *foc, |
b3d05147 | 851 | enum tcp_synack_type synack_type) |
1da177e4 | 852 | { |
2e6599cb | 853 | const struct inet_request_sock *ireq = inet_rsk(req); |
6bd023f3 | 854 | struct flowi4 fl4; |
1da177e4 | 855 | int err = -1; |
d41db5af | 856 | struct sk_buff *skb; |
1da177e4 LT |
857 | |
858 | /* First, grab a route. */ | |
ba3f7f04 | 859 | if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL) |
fd80eb94 | 860 | return -1; |
1da177e4 | 861 | |
b3d05147 | 862 | skb = tcp_make_synack(sk, dst, req, foc, synack_type); |
1da177e4 LT |
863 | |
864 | if (skb) { | |
634fb979 | 865 | __tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr); |
1da177e4 | 866 | |
634fb979 ED |
867 | err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr, |
868 | ireq->ir_rmt_addr, | |
2e6599cb | 869 | ireq->opt); |
b9df3cb8 | 870 | err = net_xmit_eval(err); |
1da177e4 LT |
871 | } |
872 | ||
1da177e4 LT |
873 | return err; |
874 | } | |
875 | ||
876 | /* | |
60236fdd | 877 | * IPv4 request_sock destructor. |
1da177e4 | 878 | */ |
60236fdd | 879 | static void tcp_v4_reqsk_destructor(struct request_sock *req) |
1da177e4 | 880 | { |
a51482bd | 881 | kfree(inet_rsk(req)->opt); |
1da177e4 LT |
882 | } |
883 | ||
cfb6eeb4 YH |
884 | #ifdef CONFIG_TCP_MD5SIG |
885 | /* | |
886 | * RFC2385 MD5 checksumming requires a mapping of | |
887 | * IP address->MD5 Key. | |
888 | * We need to maintain these in the sk structure. | |
889 | */ | |
890 | ||
891 | /* Find the Key structure for an address. */ | |
b83e3deb | 892 | struct tcp_md5sig_key *tcp_md5_do_lookup(const struct sock *sk, |
a915da9b ED |
893 | const union tcp_md5_addr *addr, |
894 | int family) | |
cfb6eeb4 | 895 | { |
fd3a154a | 896 | const struct tcp_sock *tp = tcp_sk(sk); |
a915da9b | 897 | struct tcp_md5sig_key *key; |
a915da9b | 898 | unsigned int size = sizeof(struct in_addr); |
fd3a154a | 899 | const struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 900 | |
a8afca03 ED |
901 | /* caller either holds rcu_read_lock() or socket lock */ |
902 | md5sig = rcu_dereference_check(tp->md5sig_info, | |
1e1d04e6 | 903 | lockdep_sock_is_held(sk)); |
a8afca03 | 904 | if (!md5sig) |
cfb6eeb4 | 905 | return NULL; |
a915da9b ED |
906 | #if IS_ENABLED(CONFIG_IPV6) |
907 | if (family == AF_INET6) | |
908 | size = sizeof(struct in6_addr); | |
909 | #endif | |
b67bfe0d | 910 | hlist_for_each_entry_rcu(key, &md5sig->head, node) { |
a915da9b ED |
911 | if (key->family != family) |
912 | continue; | |
913 | if (!memcmp(&key->addr, addr, size)) | |
914 | return key; | |
cfb6eeb4 YH |
915 | } |
916 | return NULL; | |
917 | } | |
a915da9b | 918 | EXPORT_SYMBOL(tcp_md5_do_lookup); |
cfb6eeb4 | 919 | |
b83e3deb | 920 | struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, |
fd3a154a | 921 | const struct sock *addr_sk) |
cfb6eeb4 | 922 | { |
b52e6921 | 923 | const union tcp_md5_addr *addr; |
a915da9b | 924 | |
b52e6921 | 925 | addr = (const union tcp_md5_addr *)&addr_sk->sk_daddr; |
a915da9b | 926 | return tcp_md5_do_lookup(sk, addr, AF_INET); |
cfb6eeb4 | 927 | } |
cfb6eeb4 YH |
928 | EXPORT_SYMBOL(tcp_v4_md5_lookup); |
929 | ||
cfb6eeb4 | 930 | /* This can be called on a newly created socket, from other files */ |
a915da9b ED |
931 | int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, |
932 | int family, const u8 *newkey, u8 newkeylen, gfp_t gfp) | |
cfb6eeb4 YH |
933 | { |
934 | /* Add Key to the list */ | |
b0a713e9 | 935 | struct tcp_md5sig_key *key; |
cfb6eeb4 | 936 | struct tcp_sock *tp = tcp_sk(sk); |
a915da9b | 937 | struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 938 | |
c0353c7b | 939 | key = tcp_md5_do_lookup(sk, addr, family); |
cfb6eeb4 YH |
940 | if (key) { |
941 | /* Pre-existing entry - just update that one. */ | |
a915da9b | 942 | memcpy(key->key, newkey, newkeylen); |
b0a713e9 | 943 | key->keylen = newkeylen; |
a915da9b ED |
944 | return 0; |
945 | } | |
260fcbeb | 946 | |
a8afca03 | 947 | md5sig = rcu_dereference_protected(tp->md5sig_info, |
1e1d04e6 | 948 | lockdep_sock_is_held(sk)); |
a915da9b ED |
949 | if (!md5sig) { |
950 | md5sig = kmalloc(sizeof(*md5sig), gfp); | |
951 | if (!md5sig) | |
cfb6eeb4 | 952 | return -ENOMEM; |
cfb6eeb4 | 953 | |
a915da9b ED |
954 | sk_nocaps_add(sk, NETIF_F_GSO_MASK); |
955 | INIT_HLIST_HEAD(&md5sig->head); | |
a8afca03 | 956 | rcu_assign_pointer(tp->md5sig_info, md5sig); |
a915da9b | 957 | } |
cfb6eeb4 | 958 | |
5f3d9cb2 | 959 | key = sock_kmalloc(sk, sizeof(*key), gfp); |
a915da9b ED |
960 | if (!key) |
961 | return -ENOMEM; | |
71cea17e | 962 | if (!tcp_alloc_md5sig_pool()) { |
5f3d9cb2 | 963 | sock_kfree_s(sk, key, sizeof(*key)); |
a915da9b | 964 | return -ENOMEM; |
cfb6eeb4 | 965 | } |
a915da9b ED |
966 | |
967 | memcpy(key->key, newkey, newkeylen); | |
968 | key->keylen = newkeylen; | |
969 | key->family = family; | |
970 | memcpy(&key->addr, addr, | |
971 | (family == AF_INET6) ? sizeof(struct in6_addr) : | |
972 | sizeof(struct in_addr)); | |
973 | hlist_add_head_rcu(&key->node, &md5sig->head); | |
cfb6eeb4 YH |
974 | return 0; |
975 | } | |
a915da9b | 976 | EXPORT_SYMBOL(tcp_md5_do_add); |
cfb6eeb4 | 977 | |
a915da9b | 978 | int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family) |
cfb6eeb4 | 979 | { |
a915da9b ED |
980 | struct tcp_md5sig_key *key; |
981 | ||
c0353c7b | 982 | key = tcp_md5_do_lookup(sk, addr, family); |
a915da9b ED |
983 | if (!key) |
984 | return -ENOENT; | |
985 | hlist_del_rcu(&key->node); | |
5f3d9cb2 | 986 | atomic_sub(sizeof(*key), &sk->sk_omem_alloc); |
a915da9b | 987 | kfree_rcu(key, rcu); |
a915da9b | 988 | return 0; |
cfb6eeb4 | 989 | } |
a915da9b | 990 | EXPORT_SYMBOL(tcp_md5_do_del); |
cfb6eeb4 | 991 | |
e0683e70 | 992 | static void tcp_clear_md5_list(struct sock *sk) |
cfb6eeb4 YH |
993 | { |
994 | struct tcp_sock *tp = tcp_sk(sk); | |
a915da9b | 995 | struct tcp_md5sig_key *key; |
b67bfe0d | 996 | struct hlist_node *n; |
a8afca03 | 997 | struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 998 | |
a8afca03 ED |
999 | md5sig = rcu_dereference_protected(tp->md5sig_info, 1); |
1000 | ||
b67bfe0d | 1001 | hlist_for_each_entry_safe(key, n, &md5sig->head, node) { |
a915da9b | 1002 | hlist_del_rcu(&key->node); |
5f3d9cb2 | 1003 | atomic_sub(sizeof(*key), &sk->sk_omem_alloc); |
a915da9b | 1004 | kfree_rcu(key, rcu); |
cfb6eeb4 YH |
1005 | } |
1006 | } | |
1007 | ||
7174259e ACM |
1008 | static int tcp_v4_parse_md5_keys(struct sock *sk, char __user *optval, |
1009 | int optlen) | |
cfb6eeb4 YH |
1010 | { |
1011 | struct tcp_md5sig cmd; | |
1012 | struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr; | |
cfb6eeb4 YH |
1013 | |
1014 | if (optlen < sizeof(cmd)) | |
1015 | return -EINVAL; | |
1016 | ||
7174259e | 1017 | if (copy_from_user(&cmd, optval, sizeof(cmd))) |
cfb6eeb4 YH |
1018 | return -EFAULT; |
1019 | ||
1020 | if (sin->sin_family != AF_INET) | |
1021 | return -EINVAL; | |
1022 | ||
64a124ed | 1023 | if (!cmd.tcpm_keylen) |
a915da9b ED |
1024 | return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr, |
1025 | AF_INET); | |
cfb6eeb4 YH |
1026 | |
1027 | if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) | |
1028 | return -EINVAL; | |
1029 | ||
a915da9b ED |
1030 | return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr, |
1031 | AF_INET, cmd.tcpm_key, cmd.tcpm_keylen, | |
1032 | GFP_KERNEL); | |
cfb6eeb4 YH |
1033 | } |
1034 | ||
19689e38 ED |
1035 | static int tcp_v4_md5_hash_headers(struct tcp_md5sig_pool *hp, |
1036 | __be32 daddr, __be32 saddr, | |
1037 | const struct tcphdr *th, int nbytes) | |
cfb6eeb4 | 1038 | { |
cfb6eeb4 | 1039 | struct tcp4_pseudohdr *bp; |
49a72dfb | 1040 | struct scatterlist sg; |
19689e38 | 1041 | struct tcphdr *_th; |
cfb6eeb4 | 1042 | |
19689e38 | 1043 | bp = hp->scratch; |
cfb6eeb4 YH |
1044 | bp->saddr = saddr; |
1045 | bp->daddr = daddr; | |
1046 | bp->pad = 0; | |
076fb722 | 1047 | bp->protocol = IPPROTO_TCP; |
49a72dfb | 1048 | bp->len = cpu_to_be16(nbytes); |
c7da57a1 | 1049 | |
19689e38 ED |
1050 | _th = (struct tcphdr *)(bp + 1); |
1051 | memcpy(_th, th, sizeof(*th)); | |
1052 | _th->check = 0; | |
1053 | ||
1054 | sg_init_one(&sg, bp, sizeof(*bp) + sizeof(*th)); | |
1055 | ahash_request_set_crypt(hp->md5_req, &sg, NULL, | |
1056 | sizeof(*bp) + sizeof(*th)); | |
cf80e0e4 | 1057 | return crypto_ahash_update(hp->md5_req); |
49a72dfb AL |
1058 | } |
1059 | ||
a915da9b | 1060 | static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, |
318cf7aa | 1061 | __be32 daddr, __be32 saddr, const struct tcphdr *th) |
49a72dfb AL |
1062 | { |
1063 | struct tcp_md5sig_pool *hp; | |
cf80e0e4 | 1064 | struct ahash_request *req; |
49a72dfb AL |
1065 | |
1066 | hp = tcp_get_md5sig_pool(); | |
1067 | if (!hp) | |
1068 | goto clear_hash_noput; | |
cf80e0e4 | 1069 | req = hp->md5_req; |
49a72dfb | 1070 | |
cf80e0e4 | 1071 | if (crypto_ahash_init(req)) |
49a72dfb | 1072 | goto clear_hash; |
19689e38 | 1073 | if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, th->doff << 2)) |
49a72dfb AL |
1074 | goto clear_hash; |
1075 | if (tcp_md5_hash_key(hp, key)) | |
1076 | goto clear_hash; | |
cf80e0e4 HX |
1077 | ahash_request_set_crypt(req, NULL, md5_hash, 0); |
1078 | if (crypto_ahash_final(req)) | |
cfb6eeb4 YH |
1079 | goto clear_hash; |
1080 | ||
cfb6eeb4 | 1081 | tcp_put_md5sig_pool(); |
cfb6eeb4 | 1082 | return 0; |
49a72dfb | 1083 | |
cfb6eeb4 YH |
1084 | clear_hash: |
1085 | tcp_put_md5sig_pool(); | |
1086 | clear_hash_noput: | |
1087 | memset(md5_hash, 0, 16); | |
49a72dfb | 1088 | return 1; |
cfb6eeb4 YH |
1089 | } |
1090 | ||
39f8e58e ED |
1091 | int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key, |
1092 | const struct sock *sk, | |
318cf7aa | 1093 | const struct sk_buff *skb) |
cfb6eeb4 | 1094 | { |
49a72dfb | 1095 | struct tcp_md5sig_pool *hp; |
cf80e0e4 | 1096 | struct ahash_request *req; |
318cf7aa | 1097 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
1098 | __be32 saddr, daddr; |
1099 | ||
39f8e58e ED |
1100 | if (sk) { /* valid for establish/request sockets */ |
1101 | saddr = sk->sk_rcv_saddr; | |
1102 | daddr = sk->sk_daddr; | |
cfb6eeb4 | 1103 | } else { |
49a72dfb AL |
1104 | const struct iphdr *iph = ip_hdr(skb); |
1105 | saddr = iph->saddr; | |
1106 | daddr = iph->daddr; | |
cfb6eeb4 | 1107 | } |
49a72dfb AL |
1108 | |
1109 | hp = tcp_get_md5sig_pool(); | |
1110 | if (!hp) | |
1111 | goto clear_hash_noput; | |
cf80e0e4 | 1112 | req = hp->md5_req; |
49a72dfb | 1113 | |
cf80e0e4 | 1114 | if (crypto_ahash_init(req)) |
49a72dfb AL |
1115 | goto clear_hash; |
1116 | ||
19689e38 | 1117 | if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, skb->len)) |
49a72dfb AL |
1118 | goto clear_hash; |
1119 | if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) | |
1120 | goto clear_hash; | |
1121 | if (tcp_md5_hash_key(hp, key)) | |
1122 | goto clear_hash; | |
cf80e0e4 HX |
1123 | ahash_request_set_crypt(req, NULL, md5_hash, 0); |
1124 | if (crypto_ahash_final(req)) | |
49a72dfb AL |
1125 | goto clear_hash; |
1126 | ||
1127 | tcp_put_md5sig_pool(); | |
1128 | return 0; | |
1129 | ||
1130 | clear_hash: | |
1131 | tcp_put_md5sig_pool(); | |
1132 | clear_hash_noput: | |
1133 | memset(md5_hash, 0, 16); | |
1134 | return 1; | |
cfb6eeb4 | 1135 | } |
49a72dfb | 1136 | EXPORT_SYMBOL(tcp_v4_md5_hash_skb); |
cfb6eeb4 | 1137 | |
ba8e275a ED |
1138 | #endif |
1139 | ||
ff74e23f | 1140 | /* Called with rcu_read_lock() */ |
ba8e275a | 1141 | static bool tcp_v4_inbound_md5_hash(const struct sock *sk, |
ff74e23f | 1142 | const struct sk_buff *skb) |
cfb6eeb4 | 1143 | { |
ba8e275a | 1144 | #ifdef CONFIG_TCP_MD5SIG |
cfb6eeb4 YH |
1145 | /* |
1146 | * This gets called for each TCP segment that arrives | |
1147 | * so we want to be efficient. | |
1148 | * We have 3 drop cases: | |
1149 | * o No MD5 hash and one expected. | |
1150 | * o MD5 hash and we're not expecting one. | |
1151 | * o MD5 hash and its wrong. | |
1152 | */ | |
cf533ea5 | 1153 | const __u8 *hash_location = NULL; |
cfb6eeb4 | 1154 | struct tcp_md5sig_key *hash_expected; |
eddc9ec5 | 1155 | const struct iphdr *iph = ip_hdr(skb); |
cf533ea5 | 1156 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 | 1157 | int genhash; |
cfb6eeb4 YH |
1158 | unsigned char newhash[16]; |
1159 | ||
a915da9b ED |
1160 | hash_expected = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&iph->saddr, |
1161 | AF_INET); | |
7d5d5525 | 1162 | hash_location = tcp_parse_md5sig_option(th); |
cfb6eeb4 | 1163 | |
cfb6eeb4 YH |
1164 | /* We've parsed the options - do we have a hash? */ |
1165 | if (!hash_expected && !hash_location) | |
a2a385d6 | 1166 | return false; |
cfb6eeb4 YH |
1167 | |
1168 | if (hash_expected && !hash_location) { | |
c10d9310 | 1169 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); |
a2a385d6 | 1170 | return true; |
cfb6eeb4 YH |
1171 | } |
1172 | ||
1173 | if (!hash_expected && hash_location) { | |
c10d9310 | 1174 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); |
a2a385d6 | 1175 | return true; |
cfb6eeb4 YH |
1176 | } |
1177 | ||
1178 | /* Okay, so this is hash_expected and hash_location - | |
1179 | * so we need to calculate the checksum. | |
1180 | */ | |
49a72dfb AL |
1181 | genhash = tcp_v4_md5_hash_skb(newhash, |
1182 | hash_expected, | |
39f8e58e | 1183 | NULL, skb); |
cfb6eeb4 YH |
1184 | |
1185 | if (genhash || memcmp(hash_location, newhash, 16) != 0) { | |
72145a68 | 1186 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); |
e87cc472 JP |
1187 | net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s\n", |
1188 | &iph->saddr, ntohs(th->source), | |
1189 | &iph->daddr, ntohs(th->dest), | |
1190 | genhash ? " tcp_v4_calc_md5_hash failed" | |
1191 | : ""); | |
a2a385d6 | 1192 | return true; |
cfb6eeb4 | 1193 | } |
a2a385d6 | 1194 | return false; |
cfb6eeb4 | 1195 | #endif |
ba8e275a ED |
1196 | return false; |
1197 | } | |
cfb6eeb4 | 1198 | |
b40cf18e ED |
1199 | static void tcp_v4_init_req(struct request_sock *req, |
1200 | const struct sock *sk_listener, | |
16bea70a OP |
1201 | struct sk_buff *skb) |
1202 | { | |
1203 | struct inet_request_sock *ireq = inet_rsk(req); | |
1204 | ||
08d2cc3b ED |
1205 | sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); |
1206 | sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); | |
16bea70a OP |
1207 | ireq->opt = tcp_v4_save_options(skb); |
1208 | } | |
1209 | ||
f964629e ED |
1210 | static struct dst_entry *tcp_v4_route_req(const struct sock *sk, |
1211 | struct flowi *fl, | |
d94e0417 OP |
1212 | const struct request_sock *req, |
1213 | bool *strict) | |
1214 | { | |
1215 | struct dst_entry *dst = inet_csk_route_req(sk, &fl->u.ip4, req); | |
1216 | ||
1217 | if (strict) { | |
1218 | if (fl->u.ip4.daddr == inet_rsk(req)->ir_rmt_addr) | |
1219 | *strict = true; | |
1220 | else | |
1221 | *strict = false; | |
1222 | } | |
1223 | ||
1224 | return dst; | |
1225 | } | |
1226 | ||
72a3effa | 1227 | struct request_sock_ops tcp_request_sock_ops __read_mostly = { |
1da177e4 | 1228 | .family = PF_INET, |
2e6599cb | 1229 | .obj_size = sizeof(struct tcp_request_sock), |
5db92c99 | 1230 | .rtx_syn_ack = tcp_rtx_synack, |
60236fdd ACM |
1231 | .send_ack = tcp_v4_reqsk_send_ack, |
1232 | .destructor = tcp_v4_reqsk_destructor, | |
1da177e4 | 1233 | .send_reset = tcp_v4_send_reset, |
688d1945 | 1234 | .syn_ack_timeout = tcp_syn_ack_timeout, |
1da177e4 LT |
1235 | }; |
1236 | ||
b2e4b3de | 1237 | static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { |
2aec4a29 | 1238 | .mss_clamp = TCP_MSS_DEFAULT, |
16bea70a | 1239 | #ifdef CONFIG_TCP_MD5SIG |
fd3a154a | 1240 | .req_md5_lookup = tcp_v4_md5_lookup, |
e3afe7b7 | 1241 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
b6332e6c | 1242 | #endif |
16bea70a | 1243 | .init_req = tcp_v4_init_req, |
fb7b37a7 OP |
1244 | #ifdef CONFIG_SYN_COOKIES |
1245 | .cookie_init_seq = cookie_v4_init_sequence, | |
1246 | #endif | |
d94e0417 | 1247 | .route_req = tcp_v4_route_req, |
936b8bdb | 1248 | .init_seq = tcp_v4_init_sequence, |
d6274bd8 | 1249 | .send_synack = tcp_v4_send_synack, |
16bea70a | 1250 | }; |
cfb6eeb4 | 1251 | |
1da177e4 LT |
1252 | int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
1253 | { | |
1da177e4 | 1254 | /* Never answer to SYNs send to broadcast or multicast */ |
511c3f92 | 1255 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
1da177e4 LT |
1256 | goto drop; |
1257 | ||
1fb6f159 OP |
1258 | return tcp_conn_request(&tcp_request_sock_ops, |
1259 | &tcp_request_sock_ipv4_ops, sk, skb); | |
1da177e4 | 1260 | |
1da177e4 | 1261 | drop: |
9caad864 | 1262 | tcp_listendrop(sk); |
1da177e4 LT |
1263 | return 0; |
1264 | } | |
4bc2f18b | 1265 | EXPORT_SYMBOL(tcp_v4_conn_request); |
1da177e4 LT |
1266 | |
1267 | ||
1268 | /* | |
1269 | * The three way handshake has completed - we got a valid synack - | |
1270 | * now create the new socket. | |
1271 | */ | |
0c27171e | 1272 | struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, |
60236fdd | 1273 | struct request_sock *req, |
5e0724d0 ED |
1274 | struct dst_entry *dst, |
1275 | struct request_sock *req_unhash, | |
1276 | bool *own_req) | |
1da177e4 | 1277 | { |
2e6599cb | 1278 | struct inet_request_sock *ireq; |
1da177e4 LT |
1279 | struct inet_sock *newinet; |
1280 | struct tcp_sock *newtp; | |
1281 | struct sock *newsk; | |
cfb6eeb4 YH |
1282 | #ifdef CONFIG_TCP_MD5SIG |
1283 | struct tcp_md5sig_key *key; | |
1284 | #endif | |
f6d8bd05 | 1285 | struct ip_options_rcu *inet_opt; |
1da177e4 LT |
1286 | |
1287 | if (sk_acceptq_is_full(sk)) | |
1288 | goto exit_overflow; | |
1289 | ||
1da177e4 LT |
1290 | newsk = tcp_create_openreq_child(sk, req, skb); |
1291 | if (!newsk) | |
093d2823 | 1292 | goto exit_nonewsk; |
1da177e4 | 1293 | |
bcd76111 | 1294 | newsk->sk_gso_type = SKB_GSO_TCPV4; |
fae6ef87 | 1295 | inet_sk_rx_dst_set(newsk, skb); |
1da177e4 LT |
1296 | |
1297 | newtp = tcp_sk(newsk); | |
1298 | newinet = inet_sk(newsk); | |
2e6599cb | 1299 | ireq = inet_rsk(req); |
d1e559d0 ED |
1300 | sk_daddr_set(newsk, ireq->ir_rmt_addr); |
1301 | sk_rcv_saddr_set(newsk, ireq->ir_loc_addr); | |
6dd9a14e | 1302 | newsk->sk_bound_dev_if = ireq->ir_iif; |
634fb979 | 1303 | newinet->inet_saddr = ireq->ir_loc_addr; |
f6d8bd05 ED |
1304 | inet_opt = ireq->opt; |
1305 | rcu_assign_pointer(newinet->inet_opt, inet_opt); | |
2e6599cb | 1306 | ireq->opt = NULL; |
463c84b9 | 1307 | newinet->mc_index = inet_iif(skb); |
eddc9ec5 | 1308 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
4c507d28 | 1309 | newinet->rcv_tos = ip_hdr(skb)->tos; |
d83d8461 | 1310 | inet_csk(newsk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
1311 | if (inet_opt) |
1312 | inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
c720c7e8 | 1313 | newinet->inet_id = newtp->write_seq ^ jiffies; |
1da177e4 | 1314 | |
dfd25fff ED |
1315 | if (!dst) { |
1316 | dst = inet_csk_route_child_sock(sk, newsk, req); | |
1317 | if (!dst) | |
1318 | goto put_and_exit; | |
1319 | } else { | |
1320 | /* syncookie case : see end of cookie_v4_check() */ | |
1321 | } | |
0e734419 DM |
1322 | sk_setup_caps(newsk, dst); |
1323 | ||
81164413 DB |
1324 | tcp_ca_openreq_child(newsk, dst); |
1325 | ||
1da177e4 | 1326 | tcp_sync_mss(newsk, dst_mtu(dst)); |
0dbaee3b | 1327 | newtp->advmss = dst_metric_advmss(dst); |
f5fff5dc TQ |
1328 | if (tcp_sk(sk)->rx_opt.user_mss && |
1329 | tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) | |
1330 | newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; | |
1331 | ||
1da177e4 LT |
1332 | tcp_initialize_rcv_mss(newsk); |
1333 | ||
cfb6eeb4 YH |
1334 | #ifdef CONFIG_TCP_MD5SIG |
1335 | /* Copy over the MD5 key from the original socket */ | |
a915da9b ED |
1336 | key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&newinet->inet_daddr, |
1337 | AF_INET); | |
00db4124 | 1338 | if (key) { |
cfb6eeb4 YH |
1339 | /* |
1340 | * We're using one, so create a matching key | |
1341 | * on the newsk structure. If we fail to get | |
1342 | * memory, then we end up not copying the key | |
1343 | * across. Shucks. | |
1344 | */ | |
a915da9b ED |
1345 | tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newinet->inet_daddr, |
1346 | AF_INET, key->key, key->keylen, GFP_ATOMIC); | |
a465419b | 1347 | sk_nocaps_add(newsk, NETIF_F_GSO_MASK); |
cfb6eeb4 YH |
1348 | } |
1349 | #endif | |
1350 | ||
0e734419 DM |
1351 | if (__inet_inherit_port(sk, newsk) < 0) |
1352 | goto put_and_exit; | |
5e0724d0 | 1353 | *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); |
805c4bc0 | 1354 | if (*own_req) |
49a496c9 | 1355 | tcp_move_syn(newtp, req); |
1da177e4 LT |
1356 | |
1357 | return newsk; | |
1358 | ||
1359 | exit_overflow: | |
c10d9310 | 1360 | NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
093d2823 BS |
1361 | exit_nonewsk: |
1362 | dst_release(dst); | |
1da177e4 | 1363 | exit: |
9caad864 | 1364 | tcp_listendrop(sk); |
1da177e4 | 1365 | return NULL; |
0e734419 | 1366 | put_and_exit: |
e337e24d CP |
1367 | inet_csk_prepare_forced_close(newsk); |
1368 | tcp_done(newsk); | |
0e734419 | 1369 | goto exit; |
1da177e4 | 1370 | } |
4bc2f18b | 1371 | EXPORT_SYMBOL(tcp_v4_syn_recv_sock); |
1da177e4 | 1372 | |
079096f1 | 1373 | static struct sock *tcp_v4_cookie_check(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 1374 | { |
079096f1 | 1375 | #ifdef CONFIG_SYN_COOKIES |
52452c54 | 1376 | const struct tcphdr *th = tcp_hdr(skb); |
1da177e4 | 1377 | |
af9b4738 | 1378 | if (!th->syn) |
461b74c3 | 1379 | sk = cookie_v4_check(sk, skb); |
1da177e4 LT |
1380 | #endif |
1381 | return sk; | |
1382 | } | |
1383 | ||
1da177e4 | 1384 | /* The socket must have it's spinlock held when we get |
e994b2f0 | 1385 | * here, unless it is a TCP_LISTEN socket. |
1da177e4 LT |
1386 | * |
1387 | * We have a potential double-lock case here, so even when | |
1388 | * doing backlog processing we use the BH locking scheme. | |
1389 | * This is because we cannot sleep with the original spinlock | |
1390 | * held. | |
1391 | */ | |
1392 | int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) | |
1393 | { | |
cfb6eeb4 | 1394 | struct sock *rsk; |
cfb6eeb4 | 1395 | |
1da177e4 | 1396 | if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ |
404e0a8b ED |
1397 | struct dst_entry *dst = sk->sk_rx_dst; |
1398 | ||
bdeab991 | 1399 | sock_rps_save_rxhash(sk, skb); |
3d97379a | 1400 | sk_mark_napi_id(sk, skb); |
404e0a8b | 1401 | if (dst) { |
505fbcf0 | 1402 | if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || |
51456b29 | 1403 | !dst->ops->check(dst, 0)) { |
92101b3b DM |
1404 | dst_release(dst); |
1405 | sk->sk_rx_dst = NULL; | |
1406 | } | |
1407 | } | |
c995ae22 | 1408 | tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len); |
1da177e4 LT |
1409 | return 0; |
1410 | } | |
1411 | ||
12e25e10 | 1412 | if (tcp_checksum_complete(skb)) |
1da177e4 LT |
1413 | goto csum_err; |
1414 | ||
1415 | if (sk->sk_state == TCP_LISTEN) { | |
079096f1 ED |
1416 | struct sock *nsk = tcp_v4_cookie_check(sk, skb); |
1417 | ||
1da177e4 LT |
1418 | if (!nsk) |
1419 | goto discard; | |
1da177e4 | 1420 | if (nsk != sk) { |
bdeab991 | 1421 | sock_rps_save_rxhash(nsk, skb); |
38cb5245 | 1422 | sk_mark_napi_id(nsk, skb); |
cfb6eeb4 YH |
1423 | if (tcp_child_process(sk, nsk, skb)) { |
1424 | rsk = nsk; | |
1da177e4 | 1425 | goto reset; |
cfb6eeb4 | 1426 | } |
1da177e4 LT |
1427 | return 0; |
1428 | } | |
ca55158c | 1429 | } else |
bdeab991 | 1430 | sock_rps_save_rxhash(sk, skb); |
ca55158c | 1431 | |
72ab4a86 | 1432 | if (tcp_rcv_state_process(sk, skb)) { |
cfb6eeb4 | 1433 | rsk = sk; |
1da177e4 | 1434 | goto reset; |
cfb6eeb4 | 1435 | } |
1da177e4 LT |
1436 | return 0; |
1437 | ||
1438 | reset: | |
cfb6eeb4 | 1439 | tcp_v4_send_reset(rsk, skb); |
1da177e4 LT |
1440 | discard: |
1441 | kfree_skb(skb); | |
1442 | /* Be careful here. If this function gets more complicated and | |
1443 | * gcc suffers from register pressure on the x86, sk (in %ebx) | |
1444 | * might be destroyed here. This current version compiles correctly, | |
1445 | * but you have been warned. | |
1446 | */ | |
1447 | return 0; | |
1448 | ||
1449 | csum_err: | |
c10d9310 ED |
1450 | TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); |
1451 | TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); | |
1da177e4 LT |
1452 | goto discard; |
1453 | } | |
4bc2f18b | 1454 | EXPORT_SYMBOL(tcp_v4_do_rcv); |
1da177e4 | 1455 | |
160eb5a6 | 1456 | void tcp_v4_early_demux(struct sk_buff *skb) |
41063e9d | 1457 | { |
41063e9d DM |
1458 | const struct iphdr *iph; |
1459 | const struct tcphdr *th; | |
1460 | struct sock *sk; | |
41063e9d | 1461 | |
41063e9d | 1462 | if (skb->pkt_type != PACKET_HOST) |
160eb5a6 | 1463 | return; |
41063e9d | 1464 | |
45f00f99 | 1465 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) |
160eb5a6 | 1466 | return; |
41063e9d DM |
1467 | |
1468 | iph = ip_hdr(skb); | |
45f00f99 | 1469 | th = tcp_hdr(skb); |
41063e9d DM |
1470 | |
1471 | if (th->doff < sizeof(struct tcphdr) / 4) | |
160eb5a6 | 1472 | return; |
41063e9d | 1473 | |
45f00f99 | 1474 | sk = __inet_lookup_established(dev_net(skb->dev), &tcp_hashinfo, |
41063e9d | 1475 | iph->saddr, th->source, |
7011d085 | 1476 | iph->daddr, ntohs(th->dest), |
9cb429d6 | 1477 | skb->skb_iif); |
41063e9d DM |
1478 | if (sk) { |
1479 | skb->sk = sk; | |
1480 | skb->destructor = sock_edemux; | |
f7e4eb03 | 1481 | if (sk_fullsock(sk)) { |
d0c294c5 | 1482 | struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); |
505fbcf0 | 1483 | |
41063e9d DM |
1484 | if (dst) |
1485 | dst = dst_check(dst, 0); | |
92101b3b | 1486 | if (dst && |
505fbcf0 | 1487 | inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) |
92101b3b | 1488 | skb_dst_set_noref(skb, dst); |
41063e9d DM |
1489 | } |
1490 | } | |
41063e9d DM |
1491 | } |
1492 | ||
b2fb4f54 ED |
1493 | /* Packet is added to VJ-style prequeue for processing in process |
1494 | * context, if a reader task is waiting. Apparently, this exciting | |
1495 | * idea (VJ's mail "Re: query about TCP header on tcp-ip" of 07 Sep 93) | |
1496 | * failed somewhere. Latency? Burstiness? Well, at least now we will | |
1497 | * see, why it failed. 8)8) --ANK | |
1498 | * | |
1499 | */ | |
1500 | bool tcp_prequeue(struct sock *sk, struct sk_buff *skb) | |
1501 | { | |
1502 | struct tcp_sock *tp = tcp_sk(sk); | |
1503 | ||
1504 | if (sysctl_tcp_low_latency || !tp->ucopy.task) | |
1505 | return false; | |
1506 | ||
1507 | if (skb->len <= tcp_hdrlen(skb) && | |
1508 | skb_queue_len(&tp->ucopy.prequeue) == 0) | |
1509 | return false; | |
1510 | ||
ca777eff ED |
1511 | /* Before escaping RCU protected region, we need to take care of skb |
1512 | * dst. Prequeue is only enabled for established sockets. | |
1513 | * For such sockets, we might need the skb dst only to set sk->sk_rx_dst | |
1514 | * Instead of doing full sk_rx_dst validity here, let's perform | |
1515 | * an optimistic check. | |
1516 | */ | |
1517 | if (likely(sk->sk_rx_dst)) | |
1518 | skb_dst_drop(skb); | |
1519 | else | |
5037e9ef | 1520 | skb_dst_force_safe(skb); |
ca777eff | 1521 | |
b2fb4f54 ED |
1522 | __skb_queue_tail(&tp->ucopy.prequeue, skb); |
1523 | tp->ucopy.memory += skb->truesize; | |
0cef6a4c ED |
1524 | if (skb_queue_len(&tp->ucopy.prequeue) >= 32 || |
1525 | tp->ucopy.memory + atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf) { | |
b2fb4f54 ED |
1526 | struct sk_buff *skb1; |
1527 | ||
1528 | BUG_ON(sock_owned_by_user(sk)); | |
0cef6a4c ED |
1529 | __NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPPREQUEUEDROPPED, |
1530 | skb_queue_len(&tp->ucopy.prequeue)); | |
b2fb4f54 | 1531 | |
0cef6a4c | 1532 | while ((skb1 = __skb_dequeue(&tp->ucopy.prequeue)) != NULL) |
b2fb4f54 | 1533 | sk_backlog_rcv(sk, skb1); |
b2fb4f54 ED |
1534 | |
1535 | tp->ucopy.memory = 0; | |
1536 | } else if (skb_queue_len(&tp->ucopy.prequeue) == 1) { | |
1537 | wake_up_interruptible_sync_poll(sk_sleep(sk), | |
1538 | POLLIN | POLLRDNORM | POLLRDBAND); | |
1539 | if (!inet_csk_ack_scheduled(sk)) | |
1540 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, | |
1541 | (3 * tcp_rto_min(sk)) / 4, | |
1542 | TCP_RTO_MAX); | |
1543 | } | |
1544 | return true; | |
1545 | } | |
1546 | EXPORT_SYMBOL(tcp_prequeue); | |
1547 | ||
c9c33212 ED |
1548 | bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) |
1549 | { | |
1550 | u32 limit = sk->sk_rcvbuf + sk->sk_sndbuf; | |
1551 | ||
1552 | /* Only socket owner can try to collapse/prune rx queues | |
1553 | * to reduce memory overhead, so add a little headroom here. | |
1554 | * Few sockets backlog are possibly concurrently non empty. | |
1555 | */ | |
1556 | limit += 64*1024; | |
1557 | ||
1558 | /* In case all data was pulled from skb frags (in __pskb_pull_tail()), | |
1559 | * we can fix skb->truesize to its real value to avoid future drops. | |
1560 | * This is valid because skb is not yet charged to the socket. | |
1561 | * It has been noticed pure SACK packets were sometimes dropped | |
1562 | * (if cooked by drivers without copybreak feature). | |
1563 | */ | |
60b1af33 | 1564 | skb_condense(skb); |
c9c33212 ED |
1565 | |
1566 | if (unlikely(sk_add_backlog(sk, skb, limit))) { | |
1567 | bh_unlock_sock(sk); | |
1568 | __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPBACKLOGDROP); | |
1569 | return true; | |
1570 | } | |
1571 | return false; | |
1572 | } | |
1573 | EXPORT_SYMBOL(tcp_add_backlog); | |
1574 | ||
ac6e7800 ED |
1575 | int tcp_filter(struct sock *sk, struct sk_buff *skb) |
1576 | { | |
1577 | struct tcphdr *th = (struct tcphdr *)skb->data; | |
1578 | unsigned int eaten = skb->len; | |
1579 | int err; | |
1580 | ||
1581 | err = sk_filter_trim_cap(sk, skb, th->doff * 4); | |
1582 | if (!err) { | |
1583 | eaten -= skb->len; | |
1584 | TCP_SKB_CB(skb)->end_seq -= eaten; | |
1585 | } | |
1586 | return err; | |
1587 | } | |
1588 | EXPORT_SYMBOL(tcp_filter); | |
1589 | ||
1da177e4 LT |
1590 | /* |
1591 | * From tcp_input.c | |
1592 | */ | |
1593 | ||
1594 | int tcp_v4_rcv(struct sk_buff *skb) | |
1595 | { | |
3b24d854 | 1596 | struct net *net = dev_net(skb->dev); |
eddc9ec5 | 1597 | const struct iphdr *iph; |
cf533ea5 | 1598 | const struct tcphdr *th; |
3b24d854 | 1599 | bool refcounted; |
1da177e4 LT |
1600 | struct sock *sk; |
1601 | int ret; | |
1602 | ||
1603 | if (skb->pkt_type != PACKET_HOST) | |
1604 | goto discard_it; | |
1605 | ||
1606 | /* Count it even if it's bad */ | |
90bbcc60 | 1607 | __TCP_INC_STATS(net, TCP_MIB_INSEGS); |
1da177e4 LT |
1608 | |
1609 | if (!pskb_may_pull(skb, sizeof(struct tcphdr))) | |
1610 | goto discard_it; | |
1611 | ||
ea1627c2 | 1612 | th = (const struct tcphdr *)skb->data; |
1da177e4 | 1613 | |
ea1627c2 | 1614 | if (unlikely(th->doff < sizeof(struct tcphdr) / 4)) |
1da177e4 LT |
1615 | goto bad_packet; |
1616 | if (!pskb_may_pull(skb, th->doff * 4)) | |
1617 | goto discard_it; | |
1618 | ||
1619 | /* An explanation is required here, I think. | |
1620 | * Packet length and doff are validated by header prediction, | |
caa20d9a | 1621 | * provided case of th->doff==0 is eliminated. |
1da177e4 | 1622 | * So, we defer the checks. */ |
ed70fcfc TH |
1623 | |
1624 | if (skb_checksum_init(skb, IPPROTO_TCP, inet_compute_pseudo)) | |
6a5dc9e5 | 1625 | goto csum_error; |
1da177e4 | 1626 | |
ea1627c2 | 1627 | th = (const struct tcphdr *)skb->data; |
eddc9ec5 | 1628 | iph = ip_hdr(skb); |
971f10ec ED |
1629 | /* This is tricky : We move IPCB at its correct location into TCP_SKB_CB() |
1630 | * barrier() makes sure compiler wont play fool^Waliasing games. | |
1631 | */ | |
1632 | memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb), | |
1633 | sizeof(struct inet_skb_parm)); | |
1634 | barrier(); | |
1635 | ||
1da177e4 LT |
1636 | TCP_SKB_CB(skb)->seq = ntohl(th->seq); |
1637 | TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + | |
1638 | skb->len - th->doff * 4); | |
1639 | TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); | |
e11ecddf | 1640 | TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); |
04317daf | 1641 | TCP_SKB_CB(skb)->tcp_tw_isn = 0; |
b82d1bb4 | 1642 | TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph); |
1da177e4 LT |
1643 | TCP_SKB_CB(skb)->sacked = 0; |
1644 | ||
4bdc3d66 | 1645 | lookup: |
a583636a | 1646 | sk = __inet_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th), th->source, |
3b24d854 | 1647 | th->dest, &refcounted); |
1da177e4 LT |
1648 | if (!sk) |
1649 | goto no_tcp_socket; | |
1650 | ||
bb134d5d ED |
1651 | process: |
1652 | if (sk->sk_state == TCP_TIME_WAIT) | |
1653 | goto do_time_wait; | |
1654 | ||
079096f1 ED |
1655 | if (sk->sk_state == TCP_NEW_SYN_RECV) { |
1656 | struct request_sock *req = inet_reqsk(sk); | |
7716682c | 1657 | struct sock *nsk; |
079096f1 ED |
1658 | |
1659 | sk = req->rsk_listener; | |
72923555 | 1660 | if (unlikely(tcp_v4_inbound_md5_hash(sk, skb))) { |
e65c332d | 1661 | sk_drops_add(sk, skb); |
72923555 ED |
1662 | reqsk_put(req); |
1663 | goto discard_it; | |
1664 | } | |
7716682c | 1665 | if (unlikely(sk->sk_state != TCP_LISTEN)) { |
f03f2e15 | 1666 | inet_csk_reqsk_queue_drop_and_put(sk, req); |
4bdc3d66 ED |
1667 | goto lookup; |
1668 | } | |
3b24d854 ED |
1669 | /* We own a reference on the listener, increase it again |
1670 | * as we might lose it too soon. | |
1671 | */ | |
7716682c | 1672 | sock_hold(sk); |
3b24d854 | 1673 | refcounted = true; |
7716682c | 1674 | nsk = tcp_check_req(sk, skb, req, false); |
079096f1 ED |
1675 | if (!nsk) { |
1676 | reqsk_put(req); | |
7716682c | 1677 | goto discard_and_relse; |
079096f1 ED |
1678 | } |
1679 | if (nsk == sk) { | |
079096f1 ED |
1680 | reqsk_put(req); |
1681 | } else if (tcp_child_process(sk, nsk, skb)) { | |
1682 | tcp_v4_send_reset(nsk, skb); | |
7716682c | 1683 | goto discard_and_relse; |
079096f1 | 1684 | } else { |
7716682c | 1685 | sock_put(sk); |
079096f1 ED |
1686 | return 0; |
1687 | } | |
1688 | } | |
6cce09f8 | 1689 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
02a1d6e7 | 1690 | __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP); |
d218d111 | 1691 | goto discard_and_relse; |
6cce09f8 | 1692 | } |
d218d111 | 1693 | |
1da177e4 LT |
1694 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
1695 | goto discard_and_relse; | |
9ea88a15 | 1696 | |
9ea88a15 DP |
1697 | if (tcp_v4_inbound_md5_hash(sk, skb)) |
1698 | goto discard_and_relse; | |
9ea88a15 | 1699 | |
b59c2701 | 1700 | nf_reset(skb); |
1da177e4 | 1701 | |
ac6e7800 | 1702 | if (tcp_filter(sk, skb)) |
1da177e4 | 1703 | goto discard_and_relse; |
ac6e7800 ED |
1704 | th = (const struct tcphdr *)skb->data; |
1705 | iph = ip_hdr(skb); | |
1da177e4 LT |
1706 | |
1707 | skb->dev = NULL; | |
1708 | ||
e994b2f0 ED |
1709 | if (sk->sk_state == TCP_LISTEN) { |
1710 | ret = tcp_v4_do_rcv(sk, skb); | |
1711 | goto put_and_return; | |
1712 | } | |
1713 | ||
1714 | sk_incoming_cpu_update(sk); | |
1715 | ||
c6366184 | 1716 | bh_lock_sock_nested(sk); |
a44d6eac | 1717 | tcp_segs_in(tcp_sk(sk), skb); |
1da177e4 LT |
1718 | ret = 0; |
1719 | if (!sock_owned_by_user(sk)) { | |
7bced397 | 1720 | if (!tcp_prequeue(sk, skb)) |
1da177e4 | 1721 | ret = tcp_v4_do_rcv(sk, skb); |
c9c33212 | 1722 | } else if (tcp_add_backlog(sk, skb)) { |
6b03a53a ZY |
1723 | goto discard_and_relse; |
1724 | } | |
1da177e4 LT |
1725 | bh_unlock_sock(sk); |
1726 | ||
e994b2f0 | 1727 | put_and_return: |
3b24d854 ED |
1728 | if (refcounted) |
1729 | sock_put(sk); | |
1da177e4 LT |
1730 | |
1731 | return ret; | |
1732 | ||
1733 | no_tcp_socket: | |
1734 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) | |
1735 | goto discard_it; | |
1736 | ||
12e25e10 | 1737 | if (tcp_checksum_complete(skb)) { |
6a5dc9e5 | 1738 | csum_error: |
90bbcc60 | 1739 | __TCP_INC_STATS(net, TCP_MIB_CSUMERRORS); |
1da177e4 | 1740 | bad_packet: |
90bbcc60 | 1741 | __TCP_INC_STATS(net, TCP_MIB_INERRS); |
1da177e4 | 1742 | } else { |
cfb6eeb4 | 1743 | tcp_v4_send_reset(NULL, skb); |
1da177e4 LT |
1744 | } |
1745 | ||
1746 | discard_it: | |
1747 | /* Discard frame. */ | |
1748 | kfree_skb(skb); | |
e905a9ed | 1749 | return 0; |
1da177e4 LT |
1750 | |
1751 | discard_and_relse: | |
532182cd | 1752 | sk_drops_add(sk, skb); |
3b24d854 ED |
1753 | if (refcounted) |
1754 | sock_put(sk); | |
1da177e4 LT |
1755 | goto discard_it; |
1756 | ||
1757 | do_time_wait: | |
1758 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { | |
9469c7b4 | 1759 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
1760 | goto discard_it; |
1761 | } | |
1762 | ||
6a5dc9e5 ED |
1763 | if (tcp_checksum_complete(skb)) { |
1764 | inet_twsk_put(inet_twsk(sk)); | |
1765 | goto csum_error; | |
1da177e4 | 1766 | } |
9469c7b4 | 1767 | switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { |
1da177e4 | 1768 | case TCP_TW_SYN: { |
c346dca1 | 1769 | struct sock *sk2 = inet_lookup_listener(dev_net(skb->dev), |
a583636a CG |
1770 | &tcp_hashinfo, skb, |
1771 | __tcp_hdrlen(th), | |
da5e3630 | 1772 | iph->saddr, th->source, |
eddc9ec5 | 1773 | iph->daddr, th->dest, |
463c84b9 | 1774 | inet_iif(skb)); |
1da177e4 | 1775 | if (sk2) { |
dbe7faa4 | 1776 | inet_twsk_deschedule_put(inet_twsk(sk)); |
1da177e4 | 1777 | sk = sk2; |
3b24d854 | 1778 | refcounted = false; |
1da177e4 LT |
1779 | goto process; |
1780 | } | |
1781 | /* Fall through to ACK */ | |
1782 | } | |
1783 | case TCP_TW_ACK: | |
1784 | tcp_v4_timewait_ack(sk, skb); | |
1785 | break; | |
1786 | case TCP_TW_RST: | |
271c3b9b FW |
1787 | tcp_v4_send_reset(sk, skb); |
1788 | inet_twsk_deschedule_put(inet_twsk(sk)); | |
1789 | goto discard_it; | |
1da177e4 LT |
1790 | case TCP_TW_SUCCESS:; |
1791 | } | |
1792 | goto discard_it; | |
1793 | } | |
1794 | ||
ccb7c410 DM |
1795 | static struct timewait_sock_ops tcp_timewait_sock_ops = { |
1796 | .twsk_obj_size = sizeof(struct tcp_timewait_sock), | |
1797 | .twsk_unique = tcp_twsk_unique, | |
1798 | .twsk_destructor= tcp_twsk_destructor, | |
ccb7c410 | 1799 | }; |
1da177e4 | 1800 | |
63d02d15 | 1801 | void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb) |
5d299f3d ED |
1802 | { |
1803 | struct dst_entry *dst = skb_dst(skb); | |
1804 | ||
5037e9ef | 1805 | if (dst && dst_hold_safe(dst)) { |
ca777eff ED |
1806 | sk->sk_rx_dst = dst; |
1807 | inet_sk(sk)->rx_dst_ifindex = skb->skb_iif; | |
1808 | } | |
5d299f3d | 1809 | } |
63d02d15 | 1810 | EXPORT_SYMBOL(inet_sk_rx_dst_set); |
5d299f3d | 1811 | |
3b401a81 | 1812 | const struct inet_connection_sock_af_ops ipv4_specific = { |
543d9cfe ACM |
1813 | .queue_xmit = ip_queue_xmit, |
1814 | .send_check = tcp_v4_send_check, | |
1815 | .rebuild_header = inet_sk_rebuild_header, | |
5d299f3d | 1816 | .sk_rx_dst_set = inet_sk_rx_dst_set, |
543d9cfe ACM |
1817 | .conn_request = tcp_v4_conn_request, |
1818 | .syn_recv_sock = tcp_v4_syn_recv_sock, | |
543d9cfe ACM |
1819 | .net_header_len = sizeof(struct iphdr), |
1820 | .setsockopt = ip_setsockopt, | |
1821 | .getsockopt = ip_getsockopt, | |
1822 | .addr2sockaddr = inet_csk_addr2sockaddr, | |
1823 | .sockaddr_len = sizeof(struct sockaddr_in), | |
3fdadf7d | 1824 | #ifdef CONFIG_COMPAT |
543d9cfe ACM |
1825 | .compat_setsockopt = compat_ip_setsockopt, |
1826 | .compat_getsockopt = compat_ip_getsockopt, | |
3fdadf7d | 1827 | #endif |
4fab9071 | 1828 | .mtu_reduced = tcp_v4_mtu_reduced, |
1da177e4 | 1829 | }; |
4bc2f18b | 1830 | EXPORT_SYMBOL(ipv4_specific); |
1da177e4 | 1831 | |
cfb6eeb4 | 1832 | #ifdef CONFIG_TCP_MD5SIG |
b2e4b3de | 1833 | static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = { |
cfb6eeb4 | 1834 | .md5_lookup = tcp_v4_md5_lookup, |
49a72dfb | 1835 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
cfb6eeb4 | 1836 | .md5_parse = tcp_v4_parse_md5_keys, |
cfb6eeb4 | 1837 | }; |
b6332e6c | 1838 | #endif |
cfb6eeb4 | 1839 | |
1da177e4 LT |
1840 | /* NOTE: A lot of things set to zero explicitly by call to |
1841 | * sk_alloc() so need not be done here. | |
1842 | */ | |
1843 | static int tcp_v4_init_sock(struct sock *sk) | |
1844 | { | |
6687e988 | 1845 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 | 1846 | |
900f65d3 | 1847 | tcp_init_sock(sk); |
1da177e4 | 1848 | |
8292a17a | 1849 | icsk->icsk_af_ops = &ipv4_specific; |
900f65d3 | 1850 | |
cfb6eeb4 | 1851 | #ifdef CONFIG_TCP_MD5SIG |
ac807fa8 | 1852 | tcp_sk(sk)->af_specific = &tcp_sock_ipv4_specific; |
cfb6eeb4 | 1853 | #endif |
1da177e4 | 1854 | |
1da177e4 LT |
1855 | return 0; |
1856 | } | |
1857 | ||
7d06b2e0 | 1858 | void tcp_v4_destroy_sock(struct sock *sk) |
1da177e4 LT |
1859 | { |
1860 | struct tcp_sock *tp = tcp_sk(sk); | |
1861 | ||
1862 | tcp_clear_xmit_timers(sk); | |
1863 | ||
6687e988 | 1864 | tcp_cleanup_congestion_control(sk); |
317a76f9 | 1865 | |
1da177e4 | 1866 | /* Cleanup up the write buffer. */ |
fe067e8a | 1867 | tcp_write_queue_purge(sk); |
1da177e4 LT |
1868 | |
1869 | /* Cleans up our, hopefully empty, out_of_order_queue. */ | |
9f5afeae | 1870 | skb_rbtree_purge(&tp->out_of_order_queue); |
1da177e4 | 1871 | |
cfb6eeb4 YH |
1872 | #ifdef CONFIG_TCP_MD5SIG |
1873 | /* Clean up the MD5 key list, if any */ | |
1874 | if (tp->md5sig_info) { | |
a915da9b | 1875 | tcp_clear_md5_list(sk); |
a8afca03 | 1876 | kfree_rcu(tp->md5sig_info, rcu); |
cfb6eeb4 YH |
1877 | tp->md5sig_info = NULL; |
1878 | } | |
1879 | #endif | |
1a2449a8 | 1880 | |
1da177e4 LT |
1881 | /* Clean prequeue, it must be empty really */ |
1882 | __skb_queue_purge(&tp->ucopy.prequeue); | |
1883 | ||
1884 | /* Clean up a referenced TCP bind bucket. */ | |
463c84b9 | 1885 | if (inet_csk(sk)->icsk_bind_hash) |
ab1e0a13 | 1886 | inet_put_port(sk); |
1da177e4 | 1887 | |
00db4124 | 1888 | BUG_ON(tp->fastopen_rsk); |
435cf559 | 1889 | |
cf60af03 YC |
1890 | /* If socket is aborted during connect operation */ |
1891 | tcp_free_fastopen_req(tp); | |
cd8ae852 | 1892 | tcp_saved_syn_free(tp); |
cf60af03 | 1893 | |
180d8cd9 | 1894 | sk_sockets_allocated_dec(sk); |
1da177e4 | 1895 | } |
1da177e4 LT |
1896 | EXPORT_SYMBOL(tcp_v4_destroy_sock); |
1897 | ||
1898 | #ifdef CONFIG_PROC_FS | |
1899 | /* Proc filesystem TCP sock list dumping. */ | |
1900 | ||
a8b690f9 TH |
1901 | /* |
1902 | * Get next listener socket follow cur. If cur is NULL, get first socket | |
1903 | * starting from bucket given in st->bucket; when st->bucket is zero the | |
1904 | * very first socket in the hash table is returned. | |
1905 | */ | |
1da177e4 LT |
1906 | static void *listening_get_next(struct seq_file *seq, void *cur) |
1907 | { | |
5799de0b | 1908 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 1909 | struct net *net = seq_file_net(seq); |
3b24d854 | 1910 | struct inet_listen_hashbucket *ilb; |
3b24d854 | 1911 | struct sock *sk = cur; |
1da177e4 LT |
1912 | |
1913 | if (!sk) { | |
3b24d854 | 1914 | get_head: |
a8b690f9 | 1915 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
9652dc2e | 1916 | spin_lock(&ilb->lock); |
3b24d854 | 1917 | sk = sk_head(&ilb->head); |
a8b690f9 | 1918 | st->offset = 0; |
1da177e4 LT |
1919 | goto get_sk; |
1920 | } | |
5caea4ea | 1921 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
1da177e4 | 1922 | ++st->num; |
a8b690f9 | 1923 | ++st->offset; |
1da177e4 | 1924 | |
3b24d854 | 1925 | sk = sk_next(sk); |
1da177e4 | 1926 | get_sk: |
3b24d854 | 1927 | sk_for_each_from(sk) { |
8475ef9f PE |
1928 | if (!net_eq(sock_net(sk), net)) |
1929 | continue; | |
3b24d854 ED |
1930 | if (sk->sk_family == st->family) |
1931 | return sk; | |
1da177e4 | 1932 | } |
9652dc2e | 1933 | spin_unlock(&ilb->lock); |
a8b690f9 | 1934 | st->offset = 0; |
3b24d854 ED |
1935 | if (++st->bucket < INET_LHTABLE_SIZE) |
1936 | goto get_head; | |
1937 | return NULL; | |
1da177e4 LT |
1938 | } |
1939 | ||
1940 | static void *listening_get_idx(struct seq_file *seq, loff_t *pos) | |
1941 | { | |
a8b690f9 TH |
1942 | struct tcp_iter_state *st = seq->private; |
1943 | void *rc; | |
1944 | ||
1945 | st->bucket = 0; | |
1946 | st->offset = 0; | |
1947 | rc = listening_get_next(seq, NULL); | |
1da177e4 LT |
1948 | |
1949 | while (rc && *pos) { | |
1950 | rc = listening_get_next(seq, rc); | |
1951 | --*pos; | |
1952 | } | |
1953 | return rc; | |
1954 | } | |
1955 | ||
05dbc7b5 | 1956 | static inline bool empty_bucket(const struct tcp_iter_state *st) |
6eac5604 | 1957 | { |
05dbc7b5 | 1958 | return hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].chain); |
6eac5604 AK |
1959 | } |
1960 | ||
a8b690f9 TH |
1961 | /* |
1962 | * Get first established socket starting from bucket given in st->bucket. | |
1963 | * If st->bucket is zero, the very first socket in the hash is returned. | |
1964 | */ | |
1da177e4 LT |
1965 | static void *established_get_first(struct seq_file *seq) |
1966 | { | |
5799de0b | 1967 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 1968 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
1969 | void *rc = NULL; |
1970 | ||
a8b690f9 TH |
1971 | st->offset = 0; |
1972 | for (; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) { | |
1da177e4 | 1973 | struct sock *sk; |
3ab5aee7 | 1974 | struct hlist_nulls_node *node; |
9db66bdc | 1975 | spinlock_t *lock = inet_ehash_lockp(&tcp_hashinfo, st->bucket); |
1da177e4 | 1976 | |
6eac5604 AK |
1977 | /* Lockless fast path for the common case of empty buckets */ |
1978 | if (empty_bucket(st)) | |
1979 | continue; | |
1980 | ||
9db66bdc | 1981 | spin_lock_bh(lock); |
3ab5aee7 | 1982 | sk_nulls_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) { |
f40c8174 | 1983 | if (sk->sk_family != st->family || |
878628fb | 1984 | !net_eq(sock_net(sk), net)) { |
1da177e4 LT |
1985 | continue; |
1986 | } | |
1987 | rc = sk; | |
1988 | goto out; | |
1989 | } | |
9db66bdc | 1990 | spin_unlock_bh(lock); |
1da177e4 LT |
1991 | } |
1992 | out: | |
1993 | return rc; | |
1994 | } | |
1995 | ||
1996 | static void *established_get_next(struct seq_file *seq, void *cur) | |
1997 | { | |
1998 | struct sock *sk = cur; | |
3ab5aee7 | 1999 | struct hlist_nulls_node *node; |
5799de0b | 2000 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2001 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2002 | |
2003 | ++st->num; | |
a8b690f9 | 2004 | ++st->offset; |
1da177e4 | 2005 | |
05dbc7b5 | 2006 | sk = sk_nulls_next(sk); |
1da177e4 | 2007 | |
3ab5aee7 | 2008 | sk_nulls_for_each_from(sk, node) { |
878628fb | 2009 | if (sk->sk_family == st->family && net_eq(sock_net(sk), net)) |
05dbc7b5 | 2010 | return sk; |
1da177e4 LT |
2011 | } |
2012 | ||
05dbc7b5 ED |
2013 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
2014 | ++st->bucket; | |
2015 | return established_get_first(seq); | |
1da177e4 LT |
2016 | } |
2017 | ||
2018 | static void *established_get_idx(struct seq_file *seq, loff_t pos) | |
2019 | { | |
a8b690f9 TH |
2020 | struct tcp_iter_state *st = seq->private; |
2021 | void *rc; | |
2022 | ||
2023 | st->bucket = 0; | |
2024 | rc = established_get_first(seq); | |
1da177e4 LT |
2025 | |
2026 | while (rc && pos) { | |
2027 | rc = established_get_next(seq, rc); | |
2028 | --pos; | |
7174259e | 2029 | } |
1da177e4 LT |
2030 | return rc; |
2031 | } | |
2032 | ||
2033 | static void *tcp_get_idx(struct seq_file *seq, loff_t pos) | |
2034 | { | |
2035 | void *rc; | |
5799de0b | 2036 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2037 | |
1da177e4 LT |
2038 | st->state = TCP_SEQ_STATE_LISTENING; |
2039 | rc = listening_get_idx(seq, &pos); | |
2040 | ||
2041 | if (!rc) { | |
1da177e4 LT |
2042 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2043 | rc = established_get_idx(seq, pos); | |
2044 | } | |
2045 | ||
2046 | return rc; | |
2047 | } | |
2048 | ||
a8b690f9 TH |
2049 | static void *tcp_seek_last_pos(struct seq_file *seq) |
2050 | { | |
2051 | struct tcp_iter_state *st = seq->private; | |
2052 | int offset = st->offset; | |
2053 | int orig_num = st->num; | |
2054 | void *rc = NULL; | |
2055 | ||
2056 | switch (st->state) { | |
a8b690f9 TH |
2057 | case TCP_SEQ_STATE_LISTENING: |
2058 | if (st->bucket >= INET_LHTABLE_SIZE) | |
2059 | break; | |
2060 | st->state = TCP_SEQ_STATE_LISTENING; | |
2061 | rc = listening_get_next(seq, NULL); | |
2062 | while (offset-- && rc) | |
2063 | rc = listening_get_next(seq, rc); | |
2064 | if (rc) | |
2065 | break; | |
2066 | st->bucket = 0; | |
05dbc7b5 | 2067 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
a8b690f9 TH |
2068 | /* Fallthrough */ |
2069 | case TCP_SEQ_STATE_ESTABLISHED: | |
a8b690f9 TH |
2070 | if (st->bucket > tcp_hashinfo.ehash_mask) |
2071 | break; | |
2072 | rc = established_get_first(seq); | |
2073 | while (offset-- && rc) | |
2074 | rc = established_get_next(seq, rc); | |
2075 | } | |
2076 | ||
2077 | st->num = orig_num; | |
2078 | ||
2079 | return rc; | |
2080 | } | |
2081 | ||
1da177e4 LT |
2082 | static void *tcp_seq_start(struct seq_file *seq, loff_t *pos) |
2083 | { | |
5799de0b | 2084 | struct tcp_iter_state *st = seq->private; |
a8b690f9 TH |
2085 | void *rc; |
2086 | ||
2087 | if (*pos && *pos == st->last_pos) { | |
2088 | rc = tcp_seek_last_pos(seq); | |
2089 | if (rc) | |
2090 | goto out; | |
2091 | } | |
2092 | ||
1da177e4 LT |
2093 | st->state = TCP_SEQ_STATE_LISTENING; |
2094 | st->num = 0; | |
a8b690f9 TH |
2095 | st->bucket = 0; |
2096 | st->offset = 0; | |
2097 | rc = *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
2098 | ||
2099 | out: | |
2100 | st->last_pos = *pos; | |
2101 | return rc; | |
1da177e4 LT |
2102 | } |
2103 | ||
2104 | static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2105 | { | |
a8b690f9 | 2106 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2107 | void *rc = NULL; |
1da177e4 LT |
2108 | |
2109 | if (v == SEQ_START_TOKEN) { | |
2110 | rc = tcp_get_idx(seq, 0); | |
2111 | goto out; | |
2112 | } | |
1da177e4 LT |
2113 | |
2114 | switch (st->state) { | |
1da177e4 LT |
2115 | case TCP_SEQ_STATE_LISTENING: |
2116 | rc = listening_get_next(seq, v); | |
2117 | if (!rc) { | |
1da177e4 | 2118 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
a8b690f9 TH |
2119 | st->bucket = 0; |
2120 | st->offset = 0; | |
1da177e4 LT |
2121 | rc = established_get_first(seq); |
2122 | } | |
2123 | break; | |
2124 | case TCP_SEQ_STATE_ESTABLISHED: | |
1da177e4 LT |
2125 | rc = established_get_next(seq, v); |
2126 | break; | |
2127 | } | |
2128 | out: | |
2129 | ++*pos; | |
a8b690f9 | 2130 | st->last_pos = *pos; |
1da177e4 LT |
2131 | return rc; |
2132 | } | |
2133 | ||
2134 | static void tcp_seq_stop(struct seq_file *seq, void *v) | |
2135 | { | |
5799de0b | 2136 | struct tcp_iter_state *st = seq->private; |
1da177e4 LT |
2137 | |
2138 | switch (st->state) { | |
1da177e4 LT |
2139 | case TCP_SEQ_STATE_LISTENING: |
2140 | if (v != SEQ_START_TOKEN) | |
9652dc2e | 2141 | spin_unlock(&tcp_hashinfo.listening_hash[st->bucket].lock); |
1da177e4 | 2142 | break; |
1da177e4 LT |
2143 | case TCP_SEQ_STATE_ESTABLISHED: |
2144 | if (v) | |
9db66bdc | 2145 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
1da177e4 LT |
2146 | break; |
2147 | } | |
2148 | } | |
2149 | ||
73cb88ec | 2150 | int tcp_seq_open(struct inode *inode, struct file *file) |
1da177e4 | 2151 | { |
d9dda78b | 2152 | struct tcp_seq_afinfo *afinfo = PDE_DATA(inode); |
1da177e4 | 2153 | struct tcp_iter_state *s; |
52d6f3f1 | 2154 | int err; |
1da177e4 | 2155 | |
52d6f3f1 DL |
2156 | err = seq_open_net(inode, file, &afinfo->seq_ops, |
2157 | sizeof(struct tcp_iter_state)); | |
2158 | if (err < 0) | |
2159 | return err; | |
f40c8174 | 2160 | |
52d6f3f1 | 2161 | s = ((struct seq_file *)file->private_data)->private; |
1da177e4 | 2162 | s->family = afinfo->family; |
688d1945 | 2163 | s->last_pos = 0; |
f40c8174 DL |
2164 | return 0; |
2165 | } | |
73cb88ec | 2166 | EXPORT_SYMBOL(tcp_seq_open); |
f40c8174 | 2167 | |
6f8b13bc | 2168 | int tcp_proc_register(struct net *net, struct tcp_seq_afinfo *afinfo) |
1da177e4 LT |
2169 | { |
2170 | int rc = 0; | |
2171 | struct proc_dir_entry *p; | |
2172 | ||
9427c4b3 DL |
2173 | afinfo->seq_ops.start = tcp_seq_start; |
2174 | afinfo->seq_ops.next = tcp_seq_next; | |
2175 | afinfo->seq_ops.stop = tcp_seq_stop; | |
2176 | ||
84841c3c | 2177 | p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net, |
73cb88ec | 2178 | afinfo->seq_fops, afinfo); |
84841c3c | 2179 | if (!p) |
1da177e4 LT |
2180 | rc = -ENOMEM; |
2181 | return rc; | |
2182 | } | |
4bc2f18b | 2183 | EXPORT_SYMBOL(tcp_proc_register); |
1da177e4 | 2184 | |
6f8b13bc | 2185 | void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo) |
1da177e4 | 2186 | { |
ece31ffd | 2187 | remove_proc_entry(afinfo->name, net->proc_net); |
1da177e4 | 2188 | } |
4bc2f18b | 2189 | EXPORT_SYMBOL(tcp_proc_unregister); |
1da177e4 | 2190 | |
d4f06873 | 2191 | static void get_openreq4(const struct request_sock *req, |
aa3a0c8c | 2192 | struct seq_file *f, int i) |
1da177e4 | 2193 | { |
2e6599cb | 2194 | const struct inet_request_sock *ireq = inet_rsk(req); |
fa76ce73 | 2195 | long delta = req->rsk_timer.expires - jiffies; |
1da177e4 | 2196 | |
5e659e4c | 2197 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
652586df | 2198 | " %02X %08X:%08X %02X:%08lX %08X %5u %8d %u %d %pK", |
1da177e4 | 2199 | i, |
634fb979 | 2200 | ireq->ir_loc_addr, |
d4f06873 | 2201 | ireq->ir_num, |
634fb979 ED |
2202 | ireq->ir_rmt_addr, |
2203 | ntohs(ireq->ir_rmt_port), | |
1da177e4 LT |
2204 | TCP_SYN_RECV, |
2205 | 0, 0, /* could print option size, but that is af dependent. */ | |
2206 | 1, /* timers active (only the expire timer) */ | |
a399a805 | 2207 | jiffies_delta_to_clock_t(delta), |
e6c022a4 | 2208 | req->num_timeout, |
aa3a0c8c ED |
2209 | from_kuid_munged(seq_user_ns(f), |
2210 | sock_i_uid(req->rsk_listener)), | |
1da177e4 LT |
2211 | 0, /* non standard timer */ |
2212 | 0, /* open_requests have no inode */ | |
d4f06873 | 2213 | 0, |
652586df | 2214 | req); |
1da177e4 LT |
2215 | } |
2216 | ||
652586df | 2217 | static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i) |
1da177e4 LT |
2218 | { |
2219 | int timer_active; | |
2220 | unsigned long timer_expires; | |
cf533ea5 | 2221 | const struct tcp_sock *tp = tcp_sk(sk); |
cf4c6bf8 | 2222 | const struct inet_connection_sock *icsk = inet_csk(sk); |
cf533ea5 | 2223 | const struct inet_sock *inet = inet_sk(sk); |
0536fcc0 | 2224 | const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; |
c720c7e8 ED |
2225 | __be32 dest = inet->inet_daddr; |
2226 | __be32 src = inet->inet_rcv_saddr; | |
2227 | __u16 destp = ntohs(inet->inet_dport); | |
2228 | __u16 srcp = ntohs(inet->inet_sport); | |
49d09007 | 2229 | int rx_queue; |
00fd38d9 | 2230 | int state; |
1da177e4 | 2231 | |
6ba8a3b1 | 2232 | if (icsk->icsk_pending == ICSK_TIME_RETRANS || |
57dde7f7 | 2233 | icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || |
6ba8a3b1 | 2234 | icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { |
1da177e4 | 2235 | timer_active = 1; |
463c84b9 ACM |
2236 | timer_expires = icsk->icsk_timeout; |
2237 | } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { | |
1da177e4 | 2238 | timer_active = 4; |
463c84b9 | 2239 | timer_expires = icsk->icsk_timeout; |
cf4c6bf8 | 2240 | } else if (timer_pending(&sk->sk_timer)) { |
1da177e4 | 2241 | timer_active = 2; |
cf4c6bf8 | 2242 | timer_expires = sk->sk_timer.expires; |
1da177e4 LT |
2243 | } else { |
2244 | timer_active = 0; | |
2245 | timer_expires = jiffies; | |
2246 | } | |
2247 | ||
00fd38d9 ED |
2248 | state = sk_state_load(sk); |
2249 | if (state == TCP_LISTEN) | |
49d09007 ED |
2250 | rx_queue = sk->sk_ack_backlog; |
2251 | else | |
00fd38d9 ED |
2252 | /* Because we don't lock the socket, |
2253 | * we might find a transient negative value. | |
49d09007 ED |
2254 | */ |
2255 | rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0); | |
2256 | ||
5e659e4c | 2257 | seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " |
652586df | 2258 | "%08X %5u %8d %lu %d %pK %lu %lu %u %u %d", |
00fd38d9 | 2259 | i, src, srcp, dest, destp, state, |
47da8ee6 | 2260 | tp->write_seq - tp->snd_una, |
49d09007 | 2261 | rx_queue, |
1da177e4 | 2262 | timer_active, |
a399a805 | 2263 | jiffies_delta_to_clock_t(timer_expires - jiffies), |
463c84b9 | 2264 | icsk->icsk_retransmits, |
a7cb5a49 | 2265 | from_kuid_munged(seq_user_ns(f), sock_i_uid(sk)), |
6687e988 | 2266 | icsk->icsk_probes_out, |
cf4c6bf8 IJ |
2267 | sock_i_ino(sk), |
2268 | atomic_read(&sk->sk_refcnt), sk, | |
7be87351 SH |
2269 | jiffies_to_clock_t(icsk->icsk_rto), |
2270 | jiffies_to_clock_t(icsk->icsk_ack.ato), | |
463c84b9 | 2271 | (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, |
1da177e4 | 2272 | tp->snd_cwnd, |
00fd38d9 ED |
2273 | state == TCP_LISTEN ? |
2274 | fastopenq->max_qlen : | |
652586df | 2275 | (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh)); |
1da177e4 LT |
2276 | } |
2277 | ||
cf533ea5 | 2278 | static void get_timewait4_sock(const struct inet_timewait_sock *tw, |
652586df | 2279 | struct seq_file *f, int i) |
1da177e4 | 2280 | { |
789f558c | 2281 | long delta = tw->tw_timer.expires - jiffies; |
23f33c2d | 2282 | __be32 dest, src; |
1da177e4 | 2283 | __u16 destp, srcp; |
1da177e4 LT |
2284 | |
2285 | dest = tw->tw_daddr; | |
2286 | src = tw->tw_rcv_saddr; | |
2287 | destp = ntohs(tw->tw_dport); | |
2288 | srcp = ntohs(tw->tw_sport); | |
2289 | ||
5e659e4c | 2290 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
652586df | 2291 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK", |
1da177e4 | 2292 | i, src, srcp, dest, destp, tw->tw_substate, 0, 0, |
a399a805 | 2293 | 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, |
652586df | 2294 | atomic_read(&tw->tw_refcnt), tw); |
1da177e4 LT |
2295 | } |
2296 | ||
2297 | #define TMPSZ 150 | |
2298 | ||
2299 | static int tcp4_seq_show(struct seq_file *seq, void *v) | |
2300 | { | |
5799de0b | 2301 | struct tcp_iter_state *st; |
05dbc7b5 | 2302 | struct sock *sk = v; |
1da177e4 | 2303 | |
652586df | 2304 | seq_setwidth(seq, TMPSZ - 1); |
1da177e4 | 2305 | if (v == SEQ_START_TOKEN) { |
652586df | 2306 | seq_puts(seq, " sl local_address rem_address st tx_queue " |
1da177e4 LT |
2307 | "rx_queue tr tm->when retrnsmt uid timeout " |
2308 | "inode"); | |
2309 | goto out; | |
2310 | } | |
2311 | st = seq->private; | |
2312 | ||
079096f1 ED |
2313 | if (sk->sk_state == TCP_TIME_WAIT) |
2314 | get_timewait4_sock(v, seq, st->num); | |
2315 | else if (sk->sk_state == TCP_NEW_SYN_RECV) | |
aa3a0c8c | 2316 | get_openreq4(v, seq, st->num); |
079096f1 ED |
2317 | else |
2318 | get_tcp4_sock(v, seq, st->num); | |
1da177e4 | 2319 | out: |
652586df | 2320 | seq_pad(seq, '\n'); |
1da177e4 LT |
2321 | return 0; |
2322 | } | |
2323 | ||
73cb88ec AV |
2324 | static const struct file_operations tcp_afinfo_seq_fops = { |
2325 | .owner = THIS_MODULE, | |
2326 | .open = tcp_seq_open, | |
2327 | .read = seq_read, | |
2328 | .llseek = seq_lseek, | |
2329 | .release = seq_release_net | |
2330 | }; | |
2331 | ||
1da177e4 | 2332 | static struct tcp_seq_afinfo tcp4_seq_afinfo = { |
1da177e4 LT |
2333 | .name = "tcp", |
2334 | .family = AF_INET, | |
73cb88ec | 2335 | .seq_fops = &tcp_afinfo_seq_fops, |
9427c4b3 DL |
2336 | .seq_ops = { |
2337 | .show = tcp4_seq_show, | |
2338 | }, | |
1da177e4 LT |
2339 | }; |
2340 | ||
2c8c1e72 | 2341 | static int __net_init tcp4_proc_init_net(struct net *net) |
757764f6 PE |
2342 | { |
2343 | return tcp_proc_register(net, &tcp4_seq_afinfo); | |
2344 | } | |
2345 | ||
2c8c1e72 | 2346 | static void __net_exit tcp4_proc_exit_net(struct net *net) |
757764f6 PE |
2347 | { |
2348 | tcp_proc_unregister(net, &tcp4_seq_afinfo); | |
2349 | } | |
2350 | ||
2351 | static struct pernet_operations tcp4_net_ops = { | |
2352 | .init = tcp4_proc_init_net, | |
2353 | .exit = tcp4_proc_exit_net, | |
2354 | }; | |
2355 | ||
1da177e4 LT |
2356 | int __init tcp4_proc_init(void) |
2357 | { | |
757764f6 | 2358 | return register_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2359 | } |
2360 | ||
2361 | void tcp4_proc_exit(void) | |
2362 | { | |
757764f6 | 2363 | unregister_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2364 | } |
2365 | #endif /* CONFIG_PROC_FS */ | |
2366 | ||
2367 | struct proto tcp_prot = { | |
2368 | .name = "TCP", | |
2369 | .owner = THIS_MODULE, | |
2370 | .close = tcp_close, | |
2371 | .connect = tcp_v4_connect, | |
2372 | .disconnect = tcp_disconnect, | |
463c84b9 | 2373 | .accept = inet_csk_accept, |
1da177e4 LT |
2374 | .ioctl = tcp_ioctl, |
2375 | .init = tcp_v4_init_sock, | |
2376 | .destroy = tcp_v4_destroy_sock, | |
2377 | .shutdown = tcp_shutdown, | |
2378 | .setsockopt = tcp_setsockopt, | |
2379 | .getsockopt = tcp_getsockopt, | |
4b9d07a4 | 2380 | .keepalive = tcp_set_keepalive, |
1da177e4 | 2381 | .recvmsg = tcp_recvmsg, |
7ba42910 CG |
2382 | .sendmsg = tcp_sendmsg, |
2383 | .sendpage = tcp_sendpage, | |
1da177e4 | 2384 | .backlog_rcv = tcp_v4_do_rcv, |
46d3ceab | 2385 | .release_cb = tcp_release_cb, |
ab1e0a13 ACM |
2386 | .hash = inet_hash, |
2387 | .unhash = inet_unhash, | |
2388 | .get_port = inet_csk_get_port, | |
1da177e4 | 2389 | .enter_memory_pressure = tcp_enter_memory_pressure, |
c9bee3b7 | 2390 | .stream_memory_free = tcp_stream_memory_free, |
1da177e4 | 2391 | .sockets_allocated = &tcp_sockets_allocated, |
0a5578cf | 2392 | .orphan_count = &tcp_orphan_count, |
1da177e4 LT |
2393 | .memory_allocated = &tcp_memory_allocated, |
2394 | .memory_pressure = &tcp_memory_pressure, | |
a4fe34bf | 2395 | .sysctl_mem = sysctl_tcp_mem, |
1da177e4 LT |
2396 | .sysctl_wmem = sysctl_tcp_wmem, |
2397 | .sysctl_rmem = sysctl_tcp_rmem, | |
2398 | .max_header = MAX_TCP_HEADER, | |
2399 | .obj_size = sizeof(struct tcp_sock), | |
3ab5aee7 | 2400 | .slab_flags = SLAB_DESTROY_BY_RCU, |
6d6ee43e | 2401 | .twsk_prot = &tcp_timewait_sock_ops, |
60236fdd | 2402 | .rsk_prot = &tcp_request_sock_ops, |
39d8cda7 | 2403 | .h.hashinfo = &tcp_hashinfo, |
7ba42910 | 2404 | .no_autobind = true, |
543d9cfe ACM |
2405 | #ifdef CONFIG_COMPAT |
2406 | .compat_setsockopt = compat_tcp_setsockopt, | |
2407 | .compat_getsockopt = compat_tcp_getsockopt, | |
d1a4c0b3 | 2408 | #endif |
c1e64e29 | 2409 | .diag_destroy = tcp_abort, |
1da177e4 | 2410 | }; |
4bc2f18b | 2411 | EXPORT_SYMBOL(tcp_prot); |
1da177e4 | 2412 | |
bdbbb852 ED |
2413 | static void __net_exit tcp_sk_exit(struct net *net) |
2414 | { | |
2415 | int cpu; | |
2416 | ||
2417 | for_each_possible_cpu(cpu) | |
2418 | inet_ctl_sock_destroy(*per_cpu_ptr(net->ipv4.tcp_sk, cpu)); | |
2419 | free_percpu(net->ipv4.tcp_sk); | |
2420 | } | |
2421 | ||
046ee902 DL |
2422 | static int __net_init tcp_sk_init(struct net *net) |
2423 | { | |
fee83d09 | 2424 | int res, cpu, cnt; |
bdbbb852 ED |
2425 | |
2426 | net->ipv4.tcp_sk = alloc_percpu(struct sock *); | |
2427 | if (!net->ipv4.tcp_sk) | |
2428 | return -ENOMEM; | |
2429 | ||
2430 | for_each_possible_cpu(cpu) { | |
2431 | struct sock *sk; | |
2432 | ||
2433 | res = inet_ctl_sock_create(&sk, PF_INET, SOCK_RAW, | |
2434 | IPPROTO_TCP, net); | |
2435 | if (res) | |
2436 | goto fail; | |
a9d6532b | 2437 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); |
bdbbb852 ED |
2438 | *per_cpu_ptr(net->ipv4.tcp_sk, cpu) = sk; |
2439 | } | |
49213555 | 2440 | |
5d134f1c | 2441 | net->ipv4.sysctl_tcp_ecn = 2; |
49213555 DB |
2442 | net->ipv4.sysctl_tcp_ecn_fallback = 1; |
2443 | ||
b0f9ca53 | 2444 | net->ipv4.sysctl_tcp_base_mss = TCP_BASE_MSS; |
6b58e0a5 | 2445 | net->ipv4.sysctl_tcp_probe_threshold = TCP_PROBE_THRESHOLD; |
05cbc0db | 2446 | net->ipv4.sysctl_tcp_probe_interval = TCP_PROBE_INTERVAL; |
046ee902 | 2447 | |
13b287e8 | 2448 | net->ipv4.sysctl_tcp_keepalive_time = TCP_KEEPALIVE_TIME; |
9bd6861b | 2449 | net->ipv4.sysctl_tcp_keepalive_probes = TCP_KEEPALIVE_PROBES; |
b840d15d | 2450 | net->ipv4.sysctl_tcp_keepalive_intvl = TCP_KEEPALIVE_INTVL; |
13b287e8 | 2451 | |
6fa25166 | 2452 | net->ipv4.sysctl_tcp_syn_retries = TCP_SYN_RETRIES; |
7c083ecb | 2453 | net->ipv4.sysctl_tcp_synack_retries = TCP_SYNACK_RETRIES; |
0aca737d | 2454 | net->ipv4.sysctl_tcp_syncookies = 1; |
1043e25f | 2455 | net->ipv4.sysctl_tcp_reordering = TCP_FASTRETRANS_THRESH; |
ae5c3f40 | 2456 | net->ipv4.sysctl_tcp_retries1 = TCP_RETR1; |
c6214a97 | 2457 | net->ipv4.sysctl_tcp_retries2 = TCP_RETR2; |
c402d9be | 2458 | net->ipv4.sysctl_tcp_orphan_retries = 0; |
1e579caa | 2459 | net->ipv4.sysctl_tcp_fin_timeout = TCP_FIN_TIMEOUT; |
4979f2d9 | 2460 | net->ipv4.sysctl_tcp_notsent_lowat = UINT_MAX; |
56ab6b93 | 2461 | net->ipv4.sysctl_tcp_tw_reuse = 0; |
12ed8244 | 2462 | |
fee83d09 | 2463 | cnt = tcp_hashinfo.ehash_mask + 1; |
1946e672 | 2464 | net->ipv4.tcp_death_row.sysctl_tw_recycle = 0; |
fee83d09 | 2465 | net->ipv4.tcp_death_row.sysctl_max_tw_buckets = (cnt + 1) / 2; |
1946e672 HY |
2466 | net->ipv4.tcp_death_row.hashinfo = &tcp_hashinfo; |
2467 | ||
fee83d09 HY |
2468 | net->ipv4.sysctl_max_syn_backlog = max(128, cnt / 256); |
2469 | ||
49213555 | 2470 | return 0; |
bdbbb852 ED |
2471 | fail: |
2472 | tcp_sk_exit(net); | |
2473 | ||
2474 | return res; | |
b099ce26 EB |
2475 | } |
2476 | ||
2477 | static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list) | |
2478 | { | |
1946e672 | 2479 | inet_twsk_purge(&tcp_hashinfo, AF_INET); |
046ee902 DL |
2480 | } |
2481 | ||
2482 | static struct pernet_operations __net_initdata tcp_sk_ops = { | |
b099ce26 EB |
2483 | .init = tcp_sk_init, |
2484 | .exit = tcp_sk_exit, | |
2485 | .exit_batch = tcp_sk_exit_batch, | |
046ee902 DL |
2486 | }; |
2487 | ||
9b0f976f | 2488 | void __init tcp_v4_init(void) |
1da177e4 | 2489 | { |
6a1b3054 | 2490 | if (register_pernet_subsys(&tcp_sk_ops)) |
1da177e4 | 2491 | panic("Failed to create the TCP control socket.\n"); |
1da177e4 | 2492 | } |