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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> | |
6797318e | 83 | #include <linux/inetdevice.h> |
1da177e4 | 84 | |
cf80e0e4 | 85 | #include <crypto/hash.h> |
cfb6eeb4 YH |
86 | #include <linux/scatterlist.h> |
87 | ||
cfb6eeb4 | 88 | #ifdef CONFIG_TCP_MD5SIG |
a915da9b | 89 | static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, |
318cf7aa | 90 | __be32 daddr, __be32 saddr, const struct tcphdr *th); |
cfb6eeb4 YH |
91 | #endif |
92 | ||
5caea4ea | 93 | struct inet_hashinfo tcp_hashinfo; |
4bc2f18b | 94 | EXPORT_SYMBOL(tcp_hashinfo); |
1da177e4 | 95 | |
84b114b9 | 96 | static u32 tcp_v4_init_seq(const struct sk_buff *skb) |
1da177e4 | 97 | { |
84b114b9 ED |
98 | return secure_tcp_seq(ip_hdr(skb)->daddr, |
99 | ip_hdr(skb)->saddr, | |
100 | tcp_hdr(skb)->dest, | |
101 | tcp_hdr(skb)->source); | |
102 | } | |
103 | ||
5d2ed052 | 104 | static u32 tcp_v4_init_ts_off(const struct net *net, const struct sk_buff *skb) |
84b114b9 | 105 | { |
5d2ed052 | 106 | return secure_tcp_ts_off(net, ip_hdr(skb)->daddr, ip_hdr(skb)->saddr); |
1da177e4 LT |
107 | } |
108 | ||
6d6ee43e ACM |
109 | int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp) |
110 | { | |
111 | const struct tcp_timewait_sock *tcptw = tcp_twsk(sktw); | |
112 | struct tcp_sock *tp = tcp_sk(sk); | |
113 | ||
114 | /* With PAWS, it is safe from the viewpoint | |
115 | of data integrity. Even without PAWS it is safe provided sequence | |
116 | spaces do not overlap i.e. at data rates <= 80Mbit/sec. | |
117 | ||
118 | Actually, the idea is close to VJ's one, only timestamp cache is | |
119 | held not per host, but per port pair and TW bucket is used as state | |
120 | holder. | |
121 | ||
122 | If TW bucket has been already destroyed we fall back to VJ's scheme | |
123 | and use initial timestamp retrieved from peer table. | |
124 | */ | |
125 | if (tcptw->tw_ts_recent_stamp && | |
56ab6b93 | 126 | (!twp || (sock_net(sk)->ipv4.sysctl_tcp_tw_reuse && |
9d729f72 | 127 | get_seconds() - tcptw->tw_ts_recent_stamp > 1))) { |
6d6ee43e ACM |
128 | tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2; |
129 | if (tp->write_seq == 0) | |
130 | tp->write_seq = 1; | |
131 | tp->rx_opt.ts_recent = tcptw->tw_ts_recent; | |
132 | tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; | |
133 | sock_hold(sktw); | |
134 | return 1; | |
135 | } | |
136 | ||
137 | return 0; | |
138 | } | |
6d6ee43e ACM |
139 | EXPORT_SYMBOL_GPL(tcp_twsk_unique); |
140 | ||
1da177e4 LT |
141 | /* This will initiate an outgoing connection. */ |
142 | int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
143 | { | |
2d7192d6 | 144 | struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
1da177e4 LT |
145 | struct inet_sock *inet = inet_sk(sk); |
146 | struct tcp_sock *tp = tcp_sk(sk); | |
dca8b089 | 147 | __be16 orig_sport, orig_dport; |
bada8adc | 148 | __be32 daddr, nexthop; |
da905bd1 | 149 | struct flowi4 *fl4; |
2d7192d6 | 150 | struct rtable *rt; |
1da177e4 | 151 | int err; |
f6d8bd05 | 152 | struct ip_options_rcu *inet_opt; |
1946e672 | 153 | struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row; |
1da177e4 LT |
154 | |
155 | if (addr_len < sizeof(struct sockaddr_in)) | |
156 | return -EINVAL; | |
157 | ||
158 | if (usin->sin_family != AF_INET) | |
159 | return -EAFNOSUPPORT; | |
160 | ||
161 | nexthop = daddr = usin->sin_addr.s_addr; | |
f6d8bd05 | 162 | inet_opt = rcu_dereference_protected(inet->inet_opt, |
1e1d04e6 | 163 | lockdep_sock_is_held(sk)); |
f6d8bd05 | 164 | if (inet_opt && inet_opt->opt.srr) { |
1da177e4 LT |
165 | if (!daddr) |
166 | return -EINVAL; | |
f6d8bd05 | 167 | nexthop = inet_opt->opt.faddr; |
1da177e4 LT |
168 | } |
169 | ||
dca8b089 DM |
170 | orig_sport = inet->inet_sport; |
171 | orig_dport = usin->sin_port; | |
da905bd1 DM |
172 | fl4 = &inet->cork.fl.u.ip4; |
173 | rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, | |
b23dd4fe DM |
174 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, |
175 | IPPROTO_TCP, | |
0e0d44ab | 176 | orig_sport, orig_dport, sk); |
b23dd4fe DM |
177 | if (IS_ERR(rt)) { |
178 | err = PTR_ERR(rt); | |
179 | if (err == -ENETUNREACH) | |
f1d8cba6 | 180 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); |
b23dd4fe | 181 | return err; |
584bdf8c | 182 | } |
1da177e4 LT |
183 | |
184 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { | |
185 | ip_rt_put(rt); | |
186 | return -ENETUNREACH; | |
187 | } | |
188 | ||
f6d8bd05 | 189 | if (!inet_opt || !inet_opt->opt.srr) |
da905bd1 | 190 | daddr = fl4->daddr; |
1da177e4 | 191 | |
c720c7e8 | 192 | if (!inet->inet_saddr) |
da905bd1 | 193 | inet->inet_saddr = fl4->saddr; |
d1e559d0 | 194 | sk_rcv_saddr_set(sk, inet->inet_saddr); |
1da177e4 | 195 | |
c720c7e8 | 196 | if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) { |
1da177e4 LT |
197 | /* Reset inherited state */ |
198 | tp->rx_opt.ts_recent = 0; | |
199 | tp->rx_opt.ts_recent_stamp = 0; | |
ee995283 PE |
200 | if (likely(!tp->repair)) |
201 | tp->write_seq = 0; | |
1da177e4 LT |
202 | } |
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 | |
00355fa5 | 237 | if (likely(!tp->repair)) { |
00355fa5 | 238 | if (!tp->write_seq) |
84b114b9 ED |
239 | tp->write_seq = secure_tcp_seq(inet->inet_saddr, |
240 | inet->inet_daddr, | |
241 | inet->inet_sport, | |
242 | usin->sin_port); | |
5d2ed052 ED |
243 | tp->tsoffset = secure_tcp_ts_off(sock_net(sk), |
244 | inet->inet_saddr, | |
84b114b9 | 245 | inet->inet_daddr); |
00355fa5 | 246 | } |
1da177e4 | 247 | |
c720c7e8 | 248 | inet->inet_id = tp->write_seq ^ jiffies; |
1da177e4 | 249 | |
19f6d3f3 WW |
250 | if (tcp_fastopen_defer_connect(sk, &err)) |
251 | return err; | |
252 | if (err) | |
253 | goto failure; | |
254 | ||
2b916477 | 255 | err = tcp_connect(sk); |
ee995283 | 256 | |
1da177e4 LT |
257 | if (err) |
258 | goto failure; | |
259 | ||
260 | return 0; | |
261 | ||
262 | failure: | |
7174259e ACM |
263 | /* |
264 | * This unhashes the socket and releases the local port, | |
265 | * if necessary. | |
266 | */ | |
1da177e4 LT |
267 | tcp_set_state(sk, TCP_CLOSE); |
268 | ip_rt_put(rt); | |
269 | sk->sk_route_caps = 0; | |
c720c7e8 | 270 | inet->inet_dport = 0; |
1da177e4 LT |
271 | return err; |
272 | } | |
4bc2f18b | 273 | EXPORT_SYMBOL(tcp_v4_connect); |
1da177e4 | 274 | |
1da177e4 | 275 | /* |
563d34d0 ED |
276 | * This routine reacts to ICMP_FRAG_NEEDED mtu indications as defined in RFC1191. |
277 | * It can be called through tcp_release_cb() if socket was owned by user | |
278 | * at the time tcp_v4_err() was called to handle ICMP message. | |
1da177e4 | 279 | */ |
4fab9071 | 280 | void tcp_v4_mtu_reduced(struct sock *sk) |
1da177e4 | 281 | { |
1da177e4 | 282 | struct inet_sock *inet = inet_sk(sk); |
02b2faaf ED |
283 | struct dst_entry *dst; |
284 | u32 mtu; | |
1da177e4 | 285 | |
02b2faaf ED |
286 | if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) |
287 | return; | |
288 | mtu = tcp_sk(sk)->mtu_info; | |
80d0a69f DM |
289 | dst = inet_csk_update_pmtu(sk, mtu); |
290 | if (!dst) | |
1da177e4 LT |
291 | return; |
292 | ||
1da177e4 LT |
293 | /* Something is about to be wrong... Remember soft error |
294 | * for the case, if this connection will not able to recover. | |
295 | */ | |
296 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) | |
297 | sk->sk_err_soft = EMSGSIZE; | |
298 | ||
299 | mtu = dst_mtu(dst); | |
300 | ||
301 | if (inet->pmtudisc != IP_PMTUDISC_DONT && | |
482fc609 | 302 | ip_sk_accept_pmtu(sk) && |
d83d8461 | 303 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
1da177e4 LT |
304 | tcp_sync_mss(sk, mtu); |
305 | ||
306 | /* Resend the TCP packet because it's | |
307 | * clear that the old packet has been | |
308 | * dropped. This is the new "fast" path mtu | |
309 | * discovery. | |
310 | */ | |
311 | tcp_simple_retransmit(sk); | |
312 | } /* else let the usual retransmit timer handle it */ | |
313 | } | |
4fab9071 | 314 | EXPORT_SYMBOL(tcp_v4_mtu_reduced); |
1da177e4 | 315 | |
55be7a9c DM |
316 | static void do_redirect(struct sk_buff *skb, struct sock *sk) |
317 | { | |
318 | struct dst_entry *dst = __sk_dst_check(sk, 0); | |
319 | ||
1ed5c48f | 320 | if (dst) |
6700c270 | 321 | dst->ops->redirect(dst, sk, skb); |
55be7a9c DM |
322 | } |
323 | ||
26e37360 ED |
324 | |
325 | /* handle ICMP messages on TCP_NEW_SYN_RECV request sockets */ | |
9cf74903 | 326 | void tcp_req_err(struct sock *sk, u32 seq, bool abort) |
26e37360 ED |
327 | { |
328 | struct request_sock *req = inet_reqsk(sk); | |
329 | struct net *net = sock_net(sk); | |
330 | ||
331 | /* ICMPs are not backlogged, hence we cannot get | |
332 | * an established socket here. | |
333 | */ | |
26e37360 | 334 | if (seq != tcp_rsk(req)->snt_isn) { |
02a1d6e7 | 335 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
9cf74903 | 336 | } else if (abort) { |
26e37360 ED |
337 | /* |
338 | * Still in SYN_RECV, just remove it silently. | |
339 | * There is no good way to pass the error to the newly | |
340 | * created socket, and POSIX does not want network | |
341 | * errors returned from accept(). | |
342 | */ | |
c6973669 | 343 | inet_csk_reqsk_queue_drop(req->rsk_listener, req); |
9caad864 | 344 | tcp_listendrop(req->rsk_listener); |
26e37360 | 345 | } |
ef84d8ce | 346 | reqsk_put(req); |
26e37360 ED |
347 | } |
348 | EXPORT_SYMBOL(tcp_req_err); | |
349 | ||
1da177e4 LT |
350 | /* |
351 | * This routine is called by the ICMP module when it gets some | |
352 | * sort of error condition. If err < 0 then the socket should | |
353 | * be closed and the error returned to the user. If err > 0 | |
354 | * it's just the icmp type << 8 | icmp code. After adjustment | |
355 | * header points to the first 8 bytes of the tcp header. We need | |
356 | * to find the appropriate port. | |
357 | * | |
358 | * The locking strategy used here is very "optimistic". When | |
359 | * someone else accesses the socket the ICMP is just dropped | |
360 | * and for some paths there is no check at all. | |
361 | * A more general error queue to queue errors for later handling | |
362 | * is probably better. | |
363 | * | |
364 | */ | |
365 | ||
4d1a2d9e | 366 | void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) |
1da177e4 | 367 | { |
b71d1d42 | 368 | const struct iphdr *iph = (const struct iphdr *)icmp_skb->data; |
4d1a2d9e | 369 | struct tcphdr *th = (struct tcphdr *)(icmp_skb->data + (iph->ihl << 2)); |
f1ecd5d9 | 370 | struct inet_connection_sock *icsk; |
1da177e4 LT |
371 | struct tcp_sock *tp; |
372 | struct inet_sock *inet; | |
4d1a2d9e DL |
373 | const int type = icmp_hdr(icmp_skb)->type; |
374 | const int code = icmp_hdr(icmp_skb)->code; | |
1da177e4 | 375 | struct sock *sk; |
f1ecd5d9 | 376 | struct sk_buff *skb; |
0a672f74 | 377 | struct request_sock *fastopen; |
9a568de4 ED |
378 | u32 seq, snd_una; |
379 | s32 remaining; | |
380 | u32 delta_us; | |
1da177e4 | 381 | int err; |
4d1a2d9e | 382 | struct net *net = dev_net(icmp_skb->dev); |
1da177e4 | 383 | |
26e37360 ED |
384 | sk = __inet_lookup_established(net, &tcp_hashinfo, iph->daddr, |
385 | th->dest, iph->saddr, ntohs(th->source), | |
3fa6f616 | 386 | inet_iif(icmp_skb), 0); |
1da177e4 | 387 | if (!sk) { |
5d3848bc | 388 | __ICMP_INC_STATS(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
389 | return; |
390 | } | |
391 | if (sk->sk_state == TCP_TIME_WAIT) { | |
9469c7b4 | 392 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
393 | return; |
394 | } | |
26e37360 ED |
395 | seq = ntohl(th->seq); |
396 | if (sk->sk_state == TCP_NEW_SYN_RECV) | |
9cf74903 ED |
397 | return tcp_req_err(sk, seq, |
398 | type == ICMP_PARAMETERPROB || | |
399 | type == ICMP_TIME_EXCEEDED || | |
400 | (type == ICMP_DEST_UNREACH && | |
401 | (code == ICMP_NET_UNREACH || | |
402 | code == ICMP_HOST_UNREACH))); | |
1da177e4 LT |
403 | |
404 | bh_lock_sock(sk); | |
405 | /* If too many ICMPs get dropped on busy | |
406 | * servers this needs to be solved differently. | |
563d34d0 ED |
407 | * We do take care of PMTU discovery (RFC1191) special case : |
408 | * we can receive locally generated ICMP messages while socket is held. | |
1da177e4 | 409 | */ |
b74aa930 ED |
410 | if (sock_owned_by_user(sk)) { |
411 | if (!(type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)) | |
02a1d6e7 | 412 | __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); |
b74aa930 | 413 | } |
1da177e4 LT |
414 | if (sk->sk_state == TCP_CLOSE) |
415 | goto out; | |
416 | ||
97e3ecd1 | 417 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
02a1d6e7 | 418 | __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP); |
97e3ecd1 | 419 | goto out; |
420 | } | |
421 | ||
f1ecd5d9 | 422 | icsk = inet_csk(sk); |
1da177e4 | 423 | tp = tcp_sk(sk); |
0a672f74 YC |
424 | /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ |
425 | fastopen = tp->fastopen_rsk; | |
426 | snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; | |
1da177e4 | 427 | if (sk->sk_state != TCP_LISTEN && |
0a672f74 | 428 | !between(seq, snd_una, tp->snd_nxt)) { |
02a1d6e7 | 429 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
1da177e4 LT |
430 | goto out; |
431 | } | |
432 | ||
433 | switch (type) { | |
55be7a9c | 434 | case ICMP_REDIRECT: |
45caeaa5 JM |
435 | if (!sock_owned_by_user(sk)) |
436 | do_redirect(icmp_skb, sk); | |
55be7a9c | 437 | goto out; |
1da177e4 LT |
438 | case ICMP_SOURCE_QUENCH: |
439 | /* Just silently ignore these. */ | |
440 | goto out; | |
441 | case ICMP_PARAMETERPROB: | |
442 | err = EPROTO; | |
443 | break; | |
444 | case ICMP_DEST_UNREACH: | |
445 | if (code > NR_ICMP_UNREACH) | |
446 | goto out; | |
447 | ||
448 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ | |
0d4f0608 ED |
449 | /* We are not interested in TCP_LISTEN and open_requests |
450 | * (SYN-ACKs send out by Linux are always <576bytes so | |
451 | * they should go through unfragmented). | |
452 | */ | |
453 | if (sk->sk_state == TCP_LISTEN) | |
454 | goto out; | |
455 | ||
563d34d0 | 456 | tp->mtu_info = info; |
144d56e9 | 457 | if (!sock_owned_by_user(sk)) { |
563d34d0 | 458 | tcp_v4_mtu_reduced(sk); |
144d56e9 | 459 | } else { |
7aa5470c | 460 | if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &sk->sk_tsq_flags)) |
144d56e9 ED |
461 | sock_hold(sk); |
462 | } | |
1da177e4 LT |
463 | goto out; |
464 | } | |
465 | ||
466 | err = icmp_err_convert[code].errno; | |
f1ecd5d9 DL |
467 | /* check if icmp_skb allows revert of backoff |
468 | * (see draft-zimmermann-tcp-lcd) */ | |
469 | if (code != ICMP_NET_UNREACH && code != ICMP_HOST_UNREACH) | |
470 | break; | |
471 | if (seq != tp->snd_una || !icsk->icsk_retransmits || | |
0a672f74 | 472 | !icsk->icsk_backoff || fastopen) |
f1ecd5d9 DL |
473 | break; |
474 | ||
8f49c270 DM |
475 | if (sock_owned_by_user(sk)) |
476 | break; | |
477 | ||
f1ecd5d9 | 478 | icsk->icsk_backoff--; |
fcdd1cf4 ED |
479 | icsk->icsk_rto = tp->srtt_us ? __tcp_set_rto(tp) : |
480 | TCP_TIMEOUT_INIT; | |
481 | icsk->icsk_rto = inet_csk_rto_backoff(icsk, TCP_RTO_MAX); | |
f1ecd5d9 DL |
482 | |
483 | skb = tcp_write_queue_head(sk); | |
484 | BUG_ON(!skb); | |
485 | ||
9a568de4 ED |
486 | tcp_mstamp_refresh(tp); |
487 | delta_us = (u32)(tp->tcp_mstamp - skb->skb_mstamp); | |
7faee5c0 | 488 | remaining = icsk->icsk_rto - |
9a568de4 | 489 | usecs_to_jiffies(delta_us); |
f1ecd5d9 | 490 | |
9a568de4 | 491 | if (remaining > 0) { |
f1ecd5d9 DL |
492 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, |
493 | remaining, TCP_RTO_MAX); | |
f1ecd5d9 DL |
494 | } else { |
495 | /* RTO revert clocked out retransmission. | |
496 | * Will retransmit now */ | |
497 | tcp_retransmit_timer(sk); | |
498 | } | |
499 | ||
1da177e4 LT |
500 | break; |
501 | case ICMP_TIME_EXCEEDED: | |
502 | err = EHOSTUNREACH; | |
503 | break; | |
504 | default: | |
505 | goto out; | |
506 | } | |
507 | ||
508 | switch (sk->sk_state) { | |
1da177e4 | 509 | case TCP_SYN_SENT: |
0a672f74 YC |
510 | case TCP_SYN_RECV: |
511 | /* Only in fast or simultaneous open. If a fast open socket is | |
512 | * is already accepted it is treated as a connected one below. | |
513 | */ | |
51456b29 | 514 | if (fastopen && !fastopen->sk) |
0a672f74 YC |
515 | break; |
516 | ||
1da177e4 | 517 | if (!sock_owned_by_user(sk)) { |
1da177e4 LT |
518 | sk->sk_err = err; |
519 | ||
520 | sk->sk_error_report(sk); | |
521 | ||
522 | tcp_done(sk); | |
523 | } else { | |
524 | sk->sk_err_soft = err; | |
525 | } | |
526 | goto out; | |
527 | } | |
528 | ||
529 | /* If we've already connected we will keep trying | |
530 | * until we time out, or the user gives up. | |
531 | * | |
532 | * rfc1122 4.2.3.9 allows to consider as hard errors | |
533 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, | |
534 | * but it is obsoleted by pmtu discovery). | |
535 | * | |
536 | * Note, that in modern internet, where routing is unreliable | |
537 | * and in each dark corner broken firewalls sit, sending random | |
538 | * errors ordered by their masters even this two messages finally lose | |
539 | * their original sense (even Linux sends invalid PORT_UNREACHs) | |
540 | * | |
541 | * Now we are in compliance with RFCs. | |
542 | * --ANK (980905) | |
543 | */ | |
544 | ||
545 | inet = inet_sk(sk); | |
546 | if (!sock_owned_by_user(sk) && inet->recverr) { | |
547 | sk->sk_err = err; | |
548 | sk->sk_error_report(sk); | |
549 | } else { /* Only an error on timeout */ | |
550 | sk->sk_err_soft = err; | |
551 | } | |
552 | ||
553 | out: | |
554 | bh_unlock_sock(sk); | |
555 | sock_put(sk); | |
556 | } | |
557 | ||
28850dc7 | 558 | void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr) |
1da177e4 | 559 | { |
aa8223c7 | 560 | struct tcphdr *th = tcp_hdr(skb); |
1da177e4 | 561 | |
84fa7933 | 562 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
419f9f89 | 563 | th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0); |
663ead3b | 564 | skb->csum_start = skb_transport_header(skb) - skb->head; |
ff1dcadb | 565 | skb->csum_offset = offsetof(struct tcphdr, check); |
1da177e4 | 566 | } else { |
419f9f89 | 567 | th->check = tcp_v4_check(skb->len, saddr, daddr, |
07f0757a | 568 | csum_partial(th, |
1da177e4 LT |
569 | th->doff << 2, |
570 | skb->csum)); | |
571 | } | |
572 | } | |
573 | ||
419f9f89 | 574 | /* This routine computes an IPv4 TCP checksum. */ |
bb296246 | 575 | void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb) |
419f9f89 | 576 | { |
cf533ea5 | 577 | const struct inet_sock *inet = inet_sk(sk); |
419f9f89 HX |
578 | |
579 | __tcp_v4_send_check(skb, inet->inet_saddr, inet->inet_daddr); | |
580 | } | |
4bc2f18b | 581 | EXPORT_SYMBOL(tcp_v4_send_check); |
419f9f89 | 582 | |
1da177e4 LT |
583 | /* |
584 | * This routine will send an RST to the other tcp. | |
585 | * | |
586 | * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.) | |
587 | * for reset. | |
588 | * Answer: if a packet caused RST, it is not for a socket | |
589 | * existing in our system, if it is matched to a socket, | |
590 | * it is just duplicate segment or bug in other side's TCP. | |
591 | * So that we build reply only basing on parameters | |
592 | * arrived with segment. | |
593 | * Exception: precedence violation. We do not implement it in any case. | |
594 | */ | |
595 | ||
a00e7444 | 596 | static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) |
1da177e4 | 597 | { |
cf533ea5 | 598 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
599 | struct { |
600 | struct tcphdr th; | |
601 | #ifdef CONFIG_TCP_MD5SIG | |
714e85be | 602 | __be32 opt[(TCPOLEN_MD5SIG_ALIGNED >> 2)]; |
cfb6eeb4 YH |
603 | #endif |
604 | } rep; | |
1da177e4 | 605 | struct ip_reply_arg arg; |
cfb6eeb4 | 606 | #ifdef CONFIG_TCP_MD5SIG |
e46787f0 | 607 | struct tcp_md5sig_key *key = NULL; |
658ddaaf SL |
608 | const __u8 *hash_location = NULL; |
609 | unsigned char newhash[16]; | |
610 | int genhash; | |
611 | struct sock *sk1 = NULL; | |
cfb6eeb4 | 612 | #endif |
a86b1e30 | 613 | struct net *net; |
1da177e4 LT |
614 | |
615 | /* Never send a reset in response to a reset. */ | |
616 | if (th->rst) | |
617 | return; | |
618 | ||
c3658e8d ED |
619 | /* If sk not NULL, it means we did a successful lookup and incoming |
620 | * route had to be correct. prequeue might have dropped our dst. | |
621 | */ | |
622 | if (!sk && skb_rtable(skb)->rt_type != RTN_LOCAL) | |
1da177e4 LT |
623 | return; |
624 | ||
625 | /* Swap the send and the receive. */ | |
cfb6eeb4 YH |
626 | memset(&rep, 0, sizeof(rep)); |
627 | rep.th.dest = th->source; | |
628 | rep.th.source = th->dest; | |
629 | rep.th.doff = sizeof(struct tcphdr) / 4; | |
630 | rep.th.rst = 1; | |
1da177e4 LT |
631 | |
632 | if (th->ack) { | |
cfb6eeb4 | 633 | rep.th.seq = th->ack_seq; |
1da177e4 | 634 | } else { |
cfb6eeb4 YH |
635 | rep.th.ack = 1; |
636 | rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin + | |
637 | skb->len - (th->doff << 2)); | |
1da177e4 LT |
638 | } |
639 | ||
7174259e | 640 | memset(&arg, 0, sizeof(arg)); |
cfb6eeb4 YH |
641 | arg.iov[0].iov_base = (unsigned char *)&rep; |
642 | arg.iov[0].iov_len = sizeof(rep.th); | |
643 | ||
0f85feae | 644 | net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); |
cfb6eeb4 | 645 | #ifdef CONFIG_TCP_MD5SIG |
3b24d854 | 646 | rcu_read_lock(); |
658ddaaf | 647 | hash_location = tcp_parse_md5sig_option(th); |
271c3b9b | 648 | if (sk && sk_fullsock(sk)) { |
e46787f0 FW |
649 | key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *) |
650 | &ip_hdr(skb)->saddr, AF_INET); | |
651 | } else if (hash_location) { | |
658ddaaf SL |
652 | /* |
653 | * active side is lost. Try to find listening socket through | |
654 | * source port, and then find md5 key through listening socket. | |
655 | * we are not loose security here: | |
656 | * Incoming packet is checked with md5 hash with finding key, | |
657 | * no RST generated if md5 hash doesn't match. | |
658 | */ | |
a583636a CG |
659 | sk1 = __inet_lookup_listener(net, &tcp_hashinfo, NULL, 0, |
660 | ip_hdr(skb)->saddr, | |
da5e3630 | 661 | th->source, ip_hdr(skb)->daddr, |
3fa6f616 DA |
662 | ntohs(th->source), inet_iif(skb), |
663 | tcp_v4_sdif(skb)); | |
658ddaaf SL |
664 | /* don't send rst if it can't find key */ |
665 | if (!sk1) | |
3b24d854 ED |
666 | goto out; |
667 | ||
658ddaaf SL |
668 | key = tcp_md5_do_lookup(sk1, (union tcp_md5_addr *) |
669 | &ip_hdr(skb)->saddr, AF_INET); | |
670 | if (!key) | |
3b24d854 ED |
671 | goto out; |
672 | ||
658ddaaf | 673 | |
39f8e58e | 674 | genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb); |
658ddaaf | 675 | if (genhash || memcmp(hash_location, newhash, 16) != 0) |
3b24d854 ED |
676 | goto out; |
677 | ||
658ddaaf SL |
678 | } |
679 | ||
cfb6eeb4 YH |
680 | if (key) { |
681 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | | |
682 | (TCPOPT_NOP << 16) | | |
683 | (TCPOPT_MD5SIG << 8) | | |
684 | TCPOLEN_MD5SIG); | |
685 | /* Update length and the length the header thinks exists */ | |
686 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
687 | rep.th.doff = arg.iov[0].iov_len / 4; | |
688 | ||
49a72dfb | 689 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[1], |
78e645cb IJ |
690 | key, ip_hdr(skb)->saddr, |
691 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
692 | } |
693 | #endif | |
eddc9ec5 ACM |
694 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
695 | ip_hdr(skb)->saddr, /* XXX */ | |
52cd5750 | 696 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
1da177e4 | 697 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; |
271c3b9b FW |
698 | arg.flags = (sk && inet_sk_transparent(sk)) ? IP_REPLY_ARG_NOSRCCHECK : 0; |
699 | ||
e2446eaa | 700 | /* When socket is gone, all binding information is lost. |
4c675258 AK |
701 | * routing might fail in this case. No choice here, if we choose to force |
702 | * input interface, we will misroute in case of asymmetric route. | |
e2446eaa | 703 | */ |
4c675258 AK |
704 | if (sk) |
705 | arg.bound_dev_if = sk->sk_bound_dev_if; | |
1da177e4 | 706 | |
271c3b9b FW |
707 | BUILD_BUG_ON(offsetof(struct sock, sk_bound_dev_if) != |
708 | offsetof(struct inet_timewait_sock, tw_bound_dev_if)); | |
709 | ||
66b13d99 | 710 | arg.tos = ip_hdr(skb)->tos; |
e2d118a1 | 711 | arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL); |
47dcc20a | 712 | local_bh_disable(); |
bdbbb852 ED |
713 | ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk), |
714 | skb, &TCP_SKB_CB(skb)->header.h4.opt, | |
24a2d43d ED |
715 | ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, |
716 | &arg, arg.iov[0].iov_len); | |
1da177e4 | 717 | |
90bbcc60 ED |
718 | __TCP_INC_STATS(net, TCP_MIB_OUTSEGS); |
719 | __TCP_INC_STATS(net, TCP_MIB_OUTRSTS); | |
47dcc20a | 720 | local_bh_enable(); |
658ddaaf SL |
721 | |
722 | #ifdef CONFIG_TCP_MD5SIG | |
3b24d854 ED |
723 | out: |
724 | rcu_read_unlock(); | |
658ddaaf | 725 | #endif |
1da177e4 LT |
726 | } |
727 | ||
728 | /* The code following below sending ACKs in SYN-RECV and TIME-WAIT states | |
729 | outside socket context is ugly, certainly. What can I do? | |
730 | */ | |
731 | ||
e2d118a1 | 732 | static void tcp_v4_send_ack(const struct sock *sk, |
e62a123b | 733 | struct sk_buff *skb, u32 seq, u32 ack, |
ee684b6f | 734 | u32 win, u32 tsval, u32 tsecr, int oif, |
88ef4a5a | 735 | struct tcp_md5sig_key *key, |
66b13d99 | 736 | int reply_flags, u8 tos) |
1da177e4 | 737 | { |
cf533ea5 | 738 | const struct tcphdr *th = tcp_hdr(skb); |
1da177e4 LT |
739 | struct { |
740 | struct tcphdr th; | |
714e85be | 741 | __be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2) |
cfb6eeb4 | 742 | #ifdef CONFIG_TCP_MD5SIG |
714e85be | 743 | + (TCPOLEN_MD5SIG_ALIGNED >> 2) |
cfb6eeb4 YH |
744 | #endif |
745 | ]; | |
1da177e4 | 746 | } rep; |
e2d118a1 | 747 | struct net *net = sock_net(sk); |
1da177e4 LT |
748 | struct ip_reply_arg arg; |
749 | ||
750 | memset(&rep.th, 0, sizeof(struct tcphdr)); | |
7174259e | 751 | memset(&arg, 0, sizeof(arg)); |
1da177e4 LT |
752 | |
753 | arg.iov[0].iov_base = (unsigned char *)&rep; | |
754 | arg.iov[0].iov_len = sizeof(rep.th); | |
ee684b6f | 755 | if (tsecr) { |
cfb6eeb4 YH |
756 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | |
757 | (TCPOPT_TIMESTAMP << 8) | | |
758 | TCPOLEN_TIMESTAMP); | |
ee684b6f AV |
759 | rep.opt[1] = htonl(tsval); |
760 | rep.opt[2] = htonl(tsecr); | |
cb48cfe8 | 761 | arg.iov[0].iov_len += TCPOLEN_TSTAMP_ALIGNED; |
1da177e4 LT |
762 | } |
763 | ||
764 | /* Swap the send and the receive. */ | |
765 | rep.th.dest = th->source; | |
766 | rep.th.source = th->dest; | |
767 | rep.th.doff = arg.iov[0].iov_len / 4; | |
768 | rep.th.seq = htonl(seq); | |
769 | rep.th.ack_seq = htonl(ack); | |
770 | rep.th.ack = 1; | |
771 | rep.th.window = htons(win); | |
772 | ||
cfb6eeb4 | 773 | #ifdef CONFIG_TCP_MD5SIG |
cfb6eeb4 | 774 | if (key) { |
ee684b6f | 775 | int offset = (tsecr) ? 3 : 0; |
cfb6eeb4 YH |
776 | |
777 | rep.opt[offset++] = htonl((TCPOPT_NOP << 24) | | |
778 | (TCPOPT_NOP << 16) | | |
779 | (TCPOPT_MD5SIG << 8) | | |
780 | TCPOLEN_MD5SIG); | |
781 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
782 | rep.th.doff = arg.iov[0].iov_len/4; | |
783 | ||
49a72dfb | 784 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[offset], |
90b7e112 AL |
785 | key, ip_hdr(skb)->saddr, |
786 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
787 | } |
788 | #endif | |
88ef4a5a | 789 | arg.flags = reply_flags; |
eddc9ec5 ACM |
790 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
791 | ip_hdr(skb)->saddr, /* XXX */ | |
1da177e4 LT |
792 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
793 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; | |
9501f972 YH |
794 | if (oif) |
795 | arg.bound_dev_if = oif; | |
66b13d99 | 796 | arg.tos = tos; |
e2d118a1 | 797 | arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL); |
47dcc20a | 798 | local_bh_disable(); |
bdbbb852 ED |
799 | ip_send_unicast_reply(*this_cpu_ptr(net->ipv4.tcp_sk), |
800 | skb, &TCP_SKB_CB(skb)->header.h4.opt, | |
24a2d43d ED |
801 | ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, |
802 | &arg, arg.iov[0].iov_len); | |
1da177e4 | 803 | |
90bbcc60 | 804 | __TCP_INC_STATS(net, TCP_MIB_OUTSEGS); |
47dcc20a | 805 | local_bh_enable(); |
1da177e4 LT |
806 | } |
807 | ||
808 | static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) | |
809 | { | |
8feaf0c0 | 810 | struct inet_timewait_sock *tw = inet_twsk(sk); |
cfb6eeb4 | 811 | struct tcp_timewait_sock *tcptw = tcp_twsk(sk); |
1da177e4 | 812 | |
e2d118a1 | 813 | tcp_v4_send_ack(sk, skb, |
e62a123b | 814 | tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, |
7174259e | 815 | tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, |
9a568de4 | 816 | tcp_time_stamp_raw() + tcptw->tw_ts_offset, |
9501f972 YH |
817 | tcptw->tw_ts_recent, |
818 | tw->tw_bound_dev_if, | |
88ef4a5a | 819 | tcp_twsk_md5_key(tcptw), |
66b13d99 ED |
820 | tw->tw_transparent ? IP_REPLY_ARG_NOSRCCHECK : 0, |
821 | tw->tw_tos | |
9501f972 | 822 | ); |
1da177e4 | 823 | |
8feaf0c0 | 824 | inet_twsk_put(tw); |
1da177e4 LT |
825 | } |
826 | ||
a00e7444 | 827 | static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, |
7174259e | 828 | struct request_sock *req) |
1da177e4 | 829 | { |
168a8f58 JC |
830 | /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV |
831 | * sk->sk_state == TCP_SYN_RECV -> for Fast Open. | |
832 | */ | |
e62a123b ED |
833 | u32 seq = (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : |
834 | tcp_sk(sk)->snd_nxt; | |
835 | ||
20a2b49f ED |
836 | /* RFC 7323 2.3 |
837 | * The window field (SEG.WND) of every outgoing segment, with the | |
838 | * exception of <SYN> segments, MUST be right-shifted by | |
839 | * Rcv.Wind.Shift bits: | |
840 | */ | |
e2d118a1 | 841 | tcp_v4_send_ack(sk, skb, seq, |
20a2b49f ED |
842 | tcp_rsk(req)->rcv_nxt, |
843 | req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, | |
9a568de4 | 844 | tcp_time_stamp_raw() + tcp_rsk(req)->ts_off, |
9501f972 YH |
845 | req->ts_recent, |
846 | 0, | |
a915da9b ED |
847 | tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->daddr, |
848 | AF_INET), | |
66b13d99 ED |
849 | inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0, |
850 | ip_hdr(skb)->tos); | |
1da177e4 LT |
851 | } |
852 | ||
1da177e4 | 853 | /* |
9bf1d83e | 854 | * Send a SYN-ACK after having received a SYN. |
60236fdd | 855 | * This still operates on a request_sock only, not on a big |
1da177e4 LT |
856 | * socket. |
857 | */ | |
0f935dbe | 858 | static int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst, |
d6274bd8 | 859 | struct flowi *fl, |
72659ecc | 860 | struct request_sock *req, |
ca6fb065 | 861 | struct tcp_fastopen_cookie *foc, |
b3d05147 | 862 | enum tcp_synack_type synack_type) |
1da177e4 | 863 | { |
2e6599cb | 864 | const struct inet_request_sock *ireq = inet_rsk(req); |
6bd023f3 | 865 | struct flowi4 fl4; |
1da177e4 | 866 | int err = -1; |
d41db5af | 867 | struct sk_buff *skb; |
1da177e4 LT |
868 | |
869 | /* First, grab a route. */ | |
ba3f7f04 | 870 | if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL) |
fd80eb94 | 871 | return -1; |
1da177e4 | 872 | |
b3d05147 | 873 | skb = tcp_make_synack(sk, dst, req, foc, synack_type); |
1da177e4 LT |
874 | |
875 | if (skb) { | |
634fb979 | 876 | __tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr); |
1da177e4 | 877 | |
634fb979 ED |
878 | err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr, |
879 | ireq->ir_rmt_addr, | |
2e6599cb | 880 | ireq->opt); |
b9df3cb8 | 881 | err = net_xmit_eval(err); |
1da177e4 LT |
882 | } |
883 | ||
1da177e4 LT |
884 | return err; |
885 | } | |
886 | ||
887 | /* | |
60236fdd | 888 | * IPv4 request_sock destructor. |
1da177e4 | 889 | */ |
60236fdd | 890 | static void tcp_v4_reqsk_destructor(struct request_sock *req) |
1da177e4 | 891 | { |
a51482bd | 892 | kfree(inet_rsk(req)->opt); |
1da177e4 LT |
893 | } |
894 | ||
cfb6eeb4 YH |
895 | #ifdef CONFIG_TCP_MD5SIG |
896 | /* | |
897 | * RFC2385 MD5 checksumming requires a mapping of | |
898 | * IP address->MD5 Key. | |
899 | * We need to maintain these in the sk structure. | |
900 | */ | |
901 | ||
902 | /* Find the Key structure for an address. */ | |
b83e3deb | 903 | struct tcp_md5sig_key *tcp_md5_do_lookup(const struct sock *sk, |
a915da9b ED |
904 | const union tcp_md5_addr *addr, |
905 | int family) | |
cfb6eeb4 | 906 | { |
fd3a154a | 907 | const struct tcp_sock *tp = tcp_sk(sk); |
a915da9b | 908 | struct tcp_md5sig_key *key; |
fd3a154a | 909 | const struct tcp_md5sig_info *md5sig; |
6797318e ID |
910 | __be32 mask; |
911 | struct tcp_md5sig_key *best_match = NULL; | |
912 | bool match; | |
cfb6eeb4 | 913 | |
a8afca03 ED |
914 | /* caller either holds rcu_read_lock() or socket lock */ |
915 | md5sig = rcu_dereference_check(tp->md5sig_info, | |
1e1d04e6 | 916 | lockdep_sock_is_held(sk)); |
a8afca03 | 917 | if (!md5sig) |
cfb6eeb4 | 918 | return NULL; |
083a0326 | 919 | |
b67bfe0d | 920 | hlist_for_each_entry_rcu(key, &md5sig->head, node) { |
a915da9b ED |
921 | if (key->family != family) |
922 | continue; | |
6797318e ID |
923 | |
924 | if (family == AF_INET) { | |
925 | mask = inet_make_mask(key->prefixlen); | |
926 | match = (key->addr.a4.s_addr & mask) == | |
927 | (addr->a4.s_addr & mask); | |
928 | #if IS_ENABLED(CONFIG_IPV6) | |
929 | } else if (family == AF_INET6) { | |
930 | match = ipv6_prefix_equal(&key->addr.a6, &addr->a6, | |
931 | key->prefixlen); | |
932 | #endif | |
933 | } else { | |
934 | match = false; | |
935 | } | |
936 | ||
937 | if (match && (!best_match || | |
938 | key->prefixlen > best_match->prefixlen)) | |
939 | best_match = key; | |
940 | } | |
941 | return best_match; | |
942 | } | |
943 | EXPORT_SYMBOL(tcp_md5_do_lookup); | |
944 | ||
e8f37d57 WF |
945 | static struct tcp_md5sig_key *tcp_md5_do_lookup_exact(const struct sock *sk, |
946 | const union tcp_md5_addr *addr, | |
947 | int family, u8 prefixlen) | |
6797318e ID |
948 | { |
949 | const struct tcp_sock *tp = tcp_sk(sk); | |
950 | struct tcp_md5sig_key *key; | |
951 | unsigned int size = sizeof(struct in_addr); | |
952 | const struct tcp_md5sig_info *md5sig; | |
953 | ||
954 | /* caller either holds rcu_read_lock() or socket lock */ | |
955 | md5sig = rcu_dereference_check(tp->md5sig_info, | |
956 | lockdep_sock_is_held(sk)); | |
957 | if (!md5sig) | |
958 | return NULL; | |
959 | #if IS_ENABLED(CONFIG_IPV6) | |
960 | if (family == AF_INET6) | |
961 | size = sizeof(struct in6_addr); | |
962 | #endif | |
963 | hlist_for_each_entry_rcu(key, &md5sig->head, node) { | |
964 | if (key->family != family) | |
965 | continue; | |
966 | if (!memcmp(&key->addr, addr, size) && | |
967 | key->prefixlen == prefixlen) | |
a915da9b | 968 | return key; |
cfb6eeb4 YH |
969 | } |
970 | return NULL; | |
971 | } | |
972 | ||
b83e3deb | 973 | struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, |
fd3a154a | 974 | const struct sock *addr_sk) |
cfb6eeb4 | 975 | { |
b52e6921 | 976 | const union tcp_md5_addr *addr; |
a915da9b | 977 | |
b52e6921 | 978 | addr = (const union tcp_md5_addr *)&addr_sk->sk_daddr; |
a915da9b | 979 | return tcp_md5_do_lookup(sk, addr, AF_INET); |
cfb6eeb4 | 980 | } |
cfb6eeb4 YH |
981 | EXPORT_SYMBOL(tcp_v4_md5_lookup); |
982 | ||
cfb6eeb4 | 983 | /* This can be called on a newly created socket, from other files */ |
a915da9b | 984 | int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, |
6797318e ID |
985 | int family, u8 prefixlen, const u8 *newkey, u8 newkeylen, |
986 | gfp_t gfp) | |
cfb6eeb4 YH |
987 | { |
988 | /* Add Key to the list */ | |
b0a713e9 | 989 | struct tcp_md5sig_key *key; |
cfb6eeb4 | 990 | struct tcp_sock *tp = tcp_sk(sk); |
a915da9b | 991 | struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 992 | |
6797318e | 993 | key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen); |
cfb6eeb4 YH |
994 | if (key) { |
995 | /* Pre-existing entry - just update that one. */ | |
a915da9b | 996 | memcpy(key->key, newkey, newkeylen); |
b0a713e9 | 997 | key->keylen = newkeylen; |
a915da9b ED |
998 | return 0; |
999 | } | |
260fcbeb | 1000 | |
a8afca03 | 1001 | md5sig = rcu_dereference_protected(tp->md5sig_info, |
1e1d04e6 | 1002 | lockdep_sock_is_held(sk)); |
a915da9b ED |
1003 | if (!md5sig) { |
1004 | md5sig = kmalloc(sizeof(*md5sig), gfp); | |
1005 | if (!md5sig) | |
cfb6eeb4 | 1006 | return -ENOMEM; |
cfb6eeb4 | 1007 | |
a915da9b ED |
1008 | sk_nocaps_add(sk, NETIF_F_GSO_MASK); |
1009 | INIT_HLIST_HEAD(&md5sig->head); | |
a8afca03 | 1010 | rcu_assign_pointer(tp->md5sig_info, md5sig); |
a915da9b | 1011 | } |
cfb6eeb4 | 1012 | |
5f3d9cb2 | 1013 | key = sock_kmalloc(sk, sizeof(*key), gfp); |
a915da9b ED |
1014 | if (!key) |
1015 | return -ENOMEM; | |
71cea17e | 1016 | if (!tcp_alloc_md5sig_pool()) { |
5f3d9cb2 | 1017 | sock_kfree_s(sk, key, sizeof(*key)); |
a915da9b | 1018 | return -ENOMEM; |
cfb6eeb4 | 1019 | } |
a915da9b ED |
1020 | |
1021 | memcpy(key->key, newkey, newkeylen); | |
1022 | key->keylen = newkeylen; | |
1023 | key->family = family; | |
6797318e | 1024 | key->prefixlen = prefixlen; |
a915da9b ED |
1025 | memcpy(&key->addr, addr, |
1026 | (family == AF_INET6) ? sizeof(struct in6_addr) : | |
1027 | sizeof(struct in_addr)); | |
1028 | hlist_add_head_rcu(&key->node, &md5sig->head); | |
cfb6eeb4 YH |
1029 | return 0; |
1030 | } | |
a915da9b | 1031 | EXPORT_SYMBOL(tcp_md5_do_add); |
cfb6eeb4 | 1032 | |
6797318e ID |
1033 | int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family, |
1034 | u8 prefixlen) | |
cfb6eeb4 | 1035 | { |
a915da9b ED |
1036 | struct tcp_md5sig_key *key; |
1037 | ||
6797318e | 1038 | key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen); |
a915da9b ED |
1039 | if (!key) |
1040 | return -ENOENT; | |
1041 | hlist_del_rcu(&key->node); | |
5f3d9cb2 | 1042 | atomic_sub(sizeof(*key), &sk->sk_omem_alloc); |
a915da9b | 1043 | kfree_rcu(key, rcu); |
a915da9b | 1044 | return 0; |
cfb6eeb4 | 1045 | } |
a915da9b | 1046 | EXPORT_SYMBOL(tcp_md5_do_del); |
cfb6eeb4 | 1047 | |
e0683e70 | 1048 | static void tcp_clear_md5_list(struct sock *sk) |
cfb6eeb4 YH |
1049 | { |
1050 | struct tcp_sock *tp = tcp_sk(sk); | |
a915da9b | 1051 | struct tcp_md5sig_key *key; |
b67bfe0d | 1052 | struct hlist_node *n; |
a8afca03 | 1053 | struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 1054 | |
a8afca03 ED |
1055 | md5sig = rcu_dereference_protected(tp->md5sig_info, 1); |
1056 | ||
b67bfe0d | 1057 | hlist_for_each_entry_safe(key, n, &md5sig->head, node) { |
a915da9b | 1058 | hlist_del_rcu(&key->node); |
5f3d9cb2 | 1059 | atomic_sub(sizeof(*key), &sk->sk_omem_alloc); |
a915da9b | 1060 | kfree_rcu(key, rcu); |
cfb6eeb4 YH |
1061 | } |
1062 | } | |
1063 | ||
8917a777 ID |
1064 | static int tcp_v4_parse_md5_keys(struct sock *sk, int optname, |
1065 | char __user *optval, int optlen) | |
cfb6eeb4 YH |
1066 | { |
1067 | struct tcp_md5sig cmd; | |
1068 | struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr; | |
8917a777 | 1069 | u8 prefixlen = 32; |
cfb6eeb4 YH |
1070 | |
1071 | if (optlen < sizeof(cmd)) | |
1072 | return -EINVAL; | |
1073 | ||
7174259e | 1074 | if (copy_from_user(&cmd, optval, sizeof(cmd))) |
cfb6eeb4 YH |
1075 | return -EFAULT; |
1076 | ||
1077 | if (sin->sin_family != AF_INET) | |
1078 | return -EINVAL; | |
1079 | ||
8917a777 ID |
1080 | if (optname == TCP_MD5SIG_EXT && |
1081 | cmd.tcpm_flags & TCP_MD5SIG_FLAG_PREFIX) { | |
1082 | prefixlen = cmd.tcpm_prefixlen; | |
1083 | if (prefixlen > 32) | |
1084 | return -EINVAL; | |
1085 | } | |
1086 | ||
64a124ed | 1087 | if (!cmd.tcpm_keylen) |
a915da9b | 1088 | return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr, |
8917a777 | 1089 | AF_INET, prefixlen); |
cfb6eeb4 YH |
1090 | |
1091 | if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) | |
1092 | return -EINVAL; | |
1093 | ||
a915da9b | 1094 | return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr, |
8917a777 | 1095 | AF_INET, prefixlen, cmd.tcpm_key, cmd.tcpm_keylen, |
a915da9b | 1096 | GFP_KERNEL); |
cfb6eeb4 YH |
1097 | } |
1098 | ||
19689e38 ED |
1099 | static int tcp_v4_md5_hash_headers(struct tcp_md5sig_pool *hp, |
1100 | __be32 daddr, __be32 saddr, | |
1101 | const struct tcphdr *th, int nbytes) | |
cfb6eeb4 | 1102 | { |
cfb6eeb4 | 1103 | struct tcp4_pseudohdr *bp; |
49a72dfb | 1104 | struct scatterlist sg; |
19689e38 | 1105 | struct tcphdr *_th; |
cfb6eeb4 | 1106 | |
19689e38 | 1107 | bp = hp->scratch; |
cfb6eeb4 YH |
1108 | bp->saddr = saddr; |
1109 | bp->daddr = daddr; | |
1110 | bp->pad = 0; | |
076fb722 | 1111 | bp->protocol = IPPROTO_TCP; |
49a72dfb | 1112 | bp->len = cpu_to_be16(nbytes); |
c7da57a1 | 1113 | |
19689e38 ED |
1114 | _th = (struct tcphdr *)(bp + 1); |
1115 | memcpy(_th, th, sizeof(*th)); | |
1116 | _th->check = 0; | |
1117 | ||
1118 | sg_init_one(&sg, bp, sizeof(*bp) + sizeof(*th)); | |
1119 | ahash_request_set_crypt(hp->md5_req, &sg, NULL, | |
1120 | sizeof(*bp) + sizeof(*th)); | |
cf80e0e4 | 1121 | return crypto_ahash_update(hp->md5_req); |
49a72dfb AL |
1122 | } |
1123 | ||
a915da9b | 1124 | static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, |
318cf7aa | 1125 | __be32 daddr, __be32 saddr, const struct tcphdr *th) |
49a72dfb AL |
1126 | { |
1127 | struct tcp_md5sig_pool *hp; | |
cf80e0e4 | 1128 | struct ahash_request *req; |
49a72dfb AL |
1129 | |
1130 | hp = tcp_get_md5sig_pool(); | |
1131 | if (!hp) | |
1132 | goto clear_hash_noput; | |
cf80e0e4 | 1133 | req = hp->md5_req; |
49a72dfb | 1134 | |
cf80e0e4 | 1135 | if (crypto_ahash_init(req)) |
49a72dfb | 1136 | goto clear_hash; |
19689e38 | 1137 | if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, th->doff << 2)) |
49a72dfb AL |
1138 | goto clear_hash; |
1139 | if (tcp_md5_hash_key(hp, key)) | |
1140 | goto clear_hash; | |
cf80e0e4 HX |
1141 | ahash_request_set_crypt(req, NULL, md5_hash, 0); |
1142 | if (crypto_ahash_final(req)) | |
cfb6eeb4 YH |
1143 | goto clear_hash; |
1144 | ||
cfb6eeb4 | 1145 | tcp_put_md5sig_pool(); |
cfb6eeb4 | 1146 | return 0; |
49a72dfb | 1147 | |
cfb6eeb4 YH |
1148 | clear_hash: |
1149 | tcp_put_md5sig_pool(); | |
1150 | clear_hash_noput: | |
1151 | memset(md5_hash, 0, 16); | |
49a72dfb | 1152 | return 1; |
cfb6eeb4 YH |
1153 | } |
1154 | ||
39f8e58e ED |
1155 | int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key, |
1156 | const struct sock *sk, | |
318cf7aa | 1157 | const struct sk_buff *skb) |
cfb6eeb4 | 1158 | { |
49a72dfb | 1159 | struct tcp_md5sig_pool *hp; |
cf80e0e4 | 1160 | struct ahash_request *req; |
318cf7aa | 1161 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
1162 | __be32 saddr, daddr; |
1163 | ||
39f8e58e ED |
1164 | if (sk) { /* valid for establish/request sockets */ |
1165 | saddr = sk->sk_rcv_saddr; | |
1166 | daddr = sk->sk_daddr; | |
cfb6eeb4 | 1167 | } else { |
49a72dfb AL |
1168 | const struct iphdr *iph = ip_hdr(skb); |
1169 | saddr = iph->saddr; | |
1170 | daddr = iph->daddr; | |
cfb6eeb4 | 1171 | } |
49a72dfb AL |
1172 | |
1173 | hp = tcp_get_md5sig_pool(); | |
1174 | if (!hp) | |
1175 | goto clear_hash_noput; | |
cf80e0e4 | 1176 | req = hp->md5_req; |
49a72dfb | 1177 | |
cf80e0e4 | 1178 | if (crypto_ahash_init(req)) |
49a72dfb AL |
1179 | goto clear_hash; |
1180 | ||
19689e38 | 1181 | if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, skb->len)) |
49a72dfb AL |
1182 | goto clear_hash; |
1183 | if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) | |
1184 | goto clear_hash; | |
1185 | if (tcp_md5_hash_key(hp, key)) | |
1186 | goto clear_hash; | |
cf80e0e4 HX |
1187 | ahash_request_set_crypt(req, NULL, md5_hash, 0); |
1188 | if (crypto_ahash_final(req)) | |
49a72dfb AL |
1189 | goto clear_hash; |
1190 | ||
1191 | tcp_put_md5sig_pool(); | |
1192 | return 0; | |
1193 | ||
1194 | clear_hash: | |
1195 | tcp_put_md5sig_pool(); | |
1196 | clear_hash_noput: | |
1197 | memset(md5_hash, 0, 16); | |
1198 | return 1; | |
cfb6eeb4 | 1199 | } |
49a72dfb | 1200 | EXPORT_SYMBOL(tcp_v4_md5_hash_skb); |
cfb6eeb4 | 1201 | |
ba8e275a ED |
1202 | #endif |
1203 | ||
ff74e23f | 1204 | /* Called with rcu_read_lock() */ |
ba8e275a | 1205 | static bool tcp_v4_inbound_md5_hash(const struct sock *sk, |
ff74e23f | 1206 | const struct sk_buff *skb) |
cfb6eeb4 | 1207 | { |
ba8e275a | 1208 | #ifdef CONFIG_TCP_MD5SIG |
cfb6eeb4 YH |
1209 | /* |
1210 | * This gets called for each TCP segment that arrives | |
1211 | * so we want to be efficient. | |
1212 | * We have 3 drop cases: | |
1213 | * o No MD5 hash and one expected. | |
1214 | * o MD5 hash and we're not expecting one. | |
1215 | * o MD5 hash and its wrong. | |
1216 | */ | |
cf533ea5 | 1217 | const __u8 *hash_location = NULL; |
cfb6eeb4 | 1218 | struct tcp_md5sig_key *hash_expected; |
eddc9ec5 | 1219 | const struct iphdr *iph = ip_hdr(skb); |
cf533ea5 | 1220 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 | 1221 | int genhash; |
cfb6eeb4 YH |
1222 | unsigned char newhash[16]; |
1223 | ||
a915da9b ED |
1224 | hash_expected = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&iph->saddr, |
1225 | AF_INET); | |
7d5d5525 | 1226 | hash_location = tcp_parse_md5sig_option(th); |
cfb6eeb4 | 1227 | |
cfb6eeb4 YH |
1228 | /* We've parsed the options - do we have a hash? */ |
1229 | if (!hash_expected && !hash_location) | |
a2a385d6 | 1230 | return false; |
cfb6eeb4 YH |
1231 | |
1232 | if (hash_expected && !hash_location) { | |
c10d9310 | 1233 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); |
a2a385d6 | 1234 | return true; |
cfb6eeb4 YH |
1235 | } |
1236 | ||
1237 | if (!hash_expected && hash_location) { | |
c10d9310 | 1238 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); |
a2a385d6 | 1239 | return true; |
cfb6eeb4 YH |
1240 | } |
1241 | ||
1242 | /* Okay, so this is hash_expected and hash_location - | |
1243 | * so we need to calculate the checksum. | |
1244 | */ | |
49a72dfb AL |
1245 | genhash = tcp_v4_md5_hash_skb(newhash, |
1246 | hash_expected, | |
39f8e58e | 1247 | NULL, skb); |
cfb6eeb4 YH |
1248 | |
1249 | if (genhash || memcmp(hash_location, newhash, 16) != 0) { | |
72145a68 | 1250 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); |
e87cc472 JP |
1251 | net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s\n", |
1252 | &iph->saddr, ntohs(th->source), | |
1253 | &iph->daddr, ntohs(th->dest), | |
1254 | genhash ? " tcp_v4_calc_md5_hash failed" | |
1255 | : ""); | |
a2a385d6 | 1256 | return true; |
cfb6eeb4 | 1257 | } |
a2a385d6 | 1258 | return false; |
cfb6eeb4 | 1259 | #endif |
ba8e275a ED |
1260 | return false; |
1261 | } | |
cfb6eeb4 | 1262 | |
b40cf18e ED |
1263 | static void tcp_v4_init_req(struct request_sock *req, |
1264 | const struct sock *sk_listener, | |
16bea70a OP |
1265 | struct sk_buff *skb) |
1266 | { | |
1267 | struct inet_request_sock *ireq = inet_rsk(req); | |
1268 | ||
08d2cc3b ED |
1269 | sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); |
1270 | sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); | |
91ed1e66 | 1271 | ireq->opt = tcp_v4_save_options(sock_net(sk_listener), skb); |
16bea70a OP |
1272 | } |
1273 | ||
f964629e ED |
1274 | static struct dst_entry *tcp_v4_route_req(const struct sock *sk, |
1275 | struct flowi *fl, | |
4396e461 | 1276 | const struct request_sock *req) |
d94e0417 | 1277 | { |
4396e461 | 1278 | return inet_csk_route_req(sk, &fl->u.ip4, req); |
d94e0417 OP |
1279 | } |
1280 | ||
72a3effa | 1281 | struct request_sock_ops tcp_request_sock_ops __read_mostly = { |
1da177e4 | 1282 | .family = PF_INET, |
2e6599cb | 1283 | .obj_size = sizeof(struct tcp_request_sock), |
5db92c99 | 1284 | .rtx_syn_ack = tcp_rtx_synack, |
60236fdd ACM |
1285 | .send_ack = tcp_v4_reqsk_send_ack, |
1286 | .destructor = tcp_v4_reqsk_destructor, | |
1da177e4 | 1287 | .send_reset = tcp_v4_send_reset, |
688d1945 | 1288 | .syn_ack_timeout = tcp_syn_ack_timeout, |
1da177e4 LT |
1289 | }; |
1290 | ||
b2e4b3de | 1291 | static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { |
2aec4a29 | 1292 | .mss_clamp = TCP_MSS_DEFAULT, |
16bea70a | 1293 | #ifdef CONFIG_TCP_MD5SIG |
fd3a154a | 1294 | .req_md5_lookup = tcp_v4_md5_lookup, |
e3afe7b7 | 1295 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
b6332e6c | 1296 | #endif |
16bea70a | 1297 | .init_req = tcp_v4_init_req, |
fb7b37a7 OP |
1298 | #ifdef CONFIG_SYN_COOKIES |
1299 | .cookie_init_seq = cookie_v4_init_sequence, | |
1300 | #endif | |
d94e0417 | 1301 | .route_req = tcp_v4_route_req, |
84b114b9 ED |
1302 | .init_seq = tcp_v4_init_seq, |
1303 | .init_ts_off = tcp_v4_init_ts_off, | |
d6274bd8 | 1304 | .send_synack = tcp_v4_send_synack, |
16bea70a | 1305 | }; |
cfb6eeb4 | 1306 | |
1da177e4 LT |
1307 | int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
1308 | { | |
1da177e4 | 1309 | /* Never answer to SYNs send to broadcast or multicast */ |
511c3f92 | 1310 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
1da177e4 LT |
1311 | goto drop; |
1312 | ||
1fb6f159 OP |
1313 | return tcp_conn_request(&tcp_request_sock_ops, |
1314 | &tcp_request_sock_ipv4_ops, sk, skb); | |
1da177e4 | 1315 | |
1da177e4 | 1316 | drop: |
9caad864 | 1317 | tcp_listendrop(sk); |
1da177e4 LT |
1318 | return 0; |
1319 | } | |
4bc2f18b | 1320 | EXPORT_SYMBOL(tcp_v4_conn_request); |
1da177e4 LT |
1321 | |
1322 | ||
1323 | /* | |
1324 | * The three way handshake has completed - we got a valid synack - | |
1325 | * now create the new socket. | |
1326 | */ | |
0c27171e | 1327 | struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, |
60236fdd | 1328 | struct request_sock *req, |
5e0724d0 ED |
1329 | struct dst_entry *dst, |
1330 | struct request_sock *req_unhash, | |
1331 | bool *own_req) | |
1da177e4 | 1332 | { |
2e6599cb | 1333 | struct inet_request_sock *ireq; |
1da177e4 LT |
1334 | struct inet_sock *newinet; |
1335 | struct tcp_sock *newtp; | |
1336 | struct sock *newsk; | |
cfb6eeb4 YH |
1337 | #ifdef CONFIG_TCP_MD5SIG |
1338 | struct tcp_md5sig_key *key; | |
1339 | #endif | |
f6d8bd05 | 1340 | struct ip_options_rcu *inet_opt; |
1da177e4 LT |
1341 | |
1342 | if (sk_acceptq_is_full(sk)) | |
1343 | goto exit_overflow; | |
1344 | ||
1da177e4 LT |
1345 | newsk = tcp_create_openreq_child(sk, req, skb); |
1346 | if (!newsk) | |
093d2823 | 1347 | goto exit_nonewsk; |
1da177e4 | 1348 | |
bcd76111 | 1349 | newsk->sk_gso_type = SKB_GSO_TCPV4; |
fae6ef87 | 1350 | inet_sk_rx_dst_set(newsk, skb); |
1da177e4 LT |
1351 | |
1352 | newtp = tcp_sk(newsk); | |
1353 | newinet = inet_sk(newsk); | |
2e6599cb | 1354 | ireq = inet_rsk(req); |
d1e559d0 ED |
1355 | sk_daddr_set(newsk, ireq->ir_rmt_addr); |
1356 | sk_rcv_saddr_set(newsk, ireq->ir_loc_addr); | |
6dd9a14e | 1357 | newsk->sk_bound_dev_if = ireq->ir_iif; |
634fb979 | 1358 | newinet->inet_saddr = ireq->ir_loc_addr; |
f6d8bd05 ED |
1359 | inet_opt = ireq->opt; |
1360 | rcu_assign_pointer(newinet->inet_opt, inet_opt); | |
2e6599cb | 1361 | ireq->opt = NULL; |
463c84b9 | 1362 | newinet->mc_index = inet_iif(skb); |
eddc9ec5 | 1363 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
4c507d28 | 1364 | newinet->rcv_tos = ip_hdr(skb)->tos; |
d83d8461 | 1365 | inet_csk(newsk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
1366 | if (inet_opt) |
1367 | inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
c720c7e8 | 1368 | newinet->inet_id = newtp->write_seq ^ jiffies; |
1da177e4 | 1369 | |
dfd25fff ED |
1370 | if (!dst) { |
1371 | dst = inet_csk_route_child_sock(sk, newsk, req); | |
1372 | if (!dst) | |
1373 | goto put_and_exit; | |
1374 | } else { | |
1375 | /* syncookie case : see end of cookie_v4_check() */ | |
1376 | } | |
0e734419 DM |
1377 | sk_setup_caps(newsk, dst); |
1378 | ||
81164413 DB |
1379 | tcp_ca_openreq_child(newsk, dst); |
1380 | ||
1da177e4 | 1381 | tcp_sync_mss(newsk, dst_mtu(dst)); |
3541f9e8 | 1382 | newtp->advmss = tcp_mss_clamp(tcp_sk(sk), dst_metric_advmss(dst)); |
f5fff5dc | 1383 | |
1da177e4 LT |
1384 | tcp_initialize_rcv_mss(newsk); |
1385 | ||
cfb6eeb4 YH |
1386 | #ifdef CONFIG_TCP_MD5SIG |
1387 | /* Copy over the MD5 key from the original socket */ | |
a915da9b ED |
1388 | key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&newinet->inet_daddr, |
1389 | AF_INET); | |
00db4124 | 1390 | if (key) { |
cfb6eeb4 YH |
1391 | /* |
1392 | * We're using one, so create a matching key | |
1393 | * on the newsk structure. If we fail to get | |
1394 | * memory, then we end up not copying the key | |
1395 | * across. Shucks. | |
1396 | */ | |
a915da9b | 1397 | tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newinet->inet_daddr, |
6797318e | 1398 | AF_INET, 32, key->key, key->keylen, GFP_ATOMIC); |
a465419b | 1399 | sk_nocaps_add(newsk, NETIF_F_GSO_MASK); |
cfb6eeb4 YH |
1400 | } |
1401 | #endif | |
1402 | ||
0e734419 DM |
1403 | if (__inet_inherit_port(sk, newsk) < 0) |
1404 | goto put_and_exit; | |
5e0724d0 | 1405 | *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); |
805c4bc0 | 1406 | if (*own_req) |
49a496c9 | 1407 | tcp_move_syn(newtp, req); |
1da177e4 LT |
1408 | |
1409 | return newsk; | |
1410 | ||
1411 | exit_overflow: | |
c10d9310 | 1412 | NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
093d2823 BS |
1413 | exit_nonewsk: |
1414 | dst_release(dst); | |
1da177e4 | 1415 | exit: |
9caad864 | 1416 | tcp_listendrop(sk); |
1da177e4 | 1417 | return NULL; |
0e734419 | 1418 | put_and_exit: |
e337e24d CP |
1419 | inet_csk_prepare_forced_close(newsk); |
1420 | tcp_done(newsk); | |
0e734419 | 1421 | goto exit; |
1da177e4 | 1422 | } |
4bc2f18b | 1423 | EXPORT_SYMBOL(tcp_v4_syn_recv_sock); |
1da177e4 | 1424 | |
079096f1 | 1425 | static struct sock *tcp_v4_cookie_check(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 1426 | { |
079096f1 | 1427 | #ifdef CONFIG_SYN_COOKIES |
52452c54 | 1428 | const struct tcphdr *th = tcp_hdr(skb); |
1da177e4 | 1429 | |
af9b4738 | 1430 | if (!th->syn) |
461b74c3 | 1431 | sk = cookie_v4_check(sk, skb); |
1da177e4 LT |
1432 | #endif |
1433 | return sk; | |
1434 | } | |
1435 | ||
1da177e4 | 1436 | /* The socket must have it's spinlock held when we get |
e994b2f0 | 1437 | * here, unless it is a TCP_LISTEN socket. |
1da177e4 LT |
1438 | * |
1439 | * We have a potential double-lock case here, so even when | |
1440 | * doing backlog processing we use the BH locking scheme. | |
1441 | * This is because we cannot sleep with the original spinlock | |
1442 | * held. | |
1443 | */ | |
1444 | int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) | |
1445 | { | |
cfb6eeb4 | 1446 | struct sock *rsk; |
cfb6eeb4 | 1447 | |
1da177e4 | 1448 | if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ |
404e0a8b ED |
1449 | struct dst_entry *dst = sk->sk_rx_dst; |
1450 | ||
bdeab991 | 1451 | sock_rps_save_rxhash(sk, skb); |
3d97379a | 1452 | sk_mark_napi_id(sk, skb); |
404e0a8b | 1453 | if (dst) { |
505fbcf0 | 1454 | if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || |
51456b29 | 1455 | !dst->ops->check(dst, 0)) { |
92101b3b DM |
1456 | dst_release(dst); |
1457 | sk->sk_rx_dst = NULL; | |
1458 | } | |
1459 | } | |
e42e24c3 | 1460 | tcp_rcv_established(sk, skb, tcp_hdr(skb)); |
1da177e4 LT |
1461 | return 0; |
1462 | } | |
1463 | ||
12e25e10 | 1464 | if (tcp_checksum_complete(skb)) |
1da177e4 LT |
1465 | goto csum_err; |
1466 | ||
1467 | if (sk->sk_state == TCP_LISTEN) { | |
079096f1 ED |
1468 | struct sock *nsk = tcp_v4_cookie_check(sk, skb); |
1469 | ||
1da177e4 LT |
1470 | if (!nsk) |
1471 | goto discard; | |
1da177e4 | 1472 | if (nsk != sk) { |
cfb6eeb4 YH |
1473 | if (tcp_child_process(sk, nsk, skb)) { |
1474 | rsk = nsk; | |
1da177e4 | 1475 | goto reset; |
cfb6eeb4 | 1476 | } |
1da177e4 LT |
1477 | return 0; |
1478 | } | |
ca55158c | 1479 | } else |
bdeab991 | 1480 | sock_rps_save_rxhash(sk, skb); |
ca55158c | 1481 | |
72ab4a86 | 1482 | if (tcp_rcv_state_process(sk, skb)) { |
cfb6eeb4 | 1483 | rsk = sk; |
1da177e4 | 1484 | goto reset; |
cfb6eeb4 | 1485 | } |
1da177e4 LT |
1486 | return 0; |
1487 | ||
1488 | reset: | |
cfb6eeb4 | 1489 | tcp_v4_send_reset(rsk, skb); |
1da177e4 LT |
1490 | discard: |
1491 | kfree_skb(skb); | |
1492 | /* Be careful here. If this function gets more complicated and | |
1493 | * gcc suffers from register pressure on the x86, sk (in %ebx) | |
1494 | * might be destroyed here. This current version compiles correctly, | |
1495 | * but you have been warned. | |
1496 | */ | |
1497 | return 0; | |
1498 | ||
1499 | csum_err: | |
c10d9310 ED |
1500 | TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); |
1501 | TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); | |
1da177e4 LT |
1502 | goto discard; |
1503 | } | |
4bc2f18b | 1504 | EXPORT_SYMBOL(tcp_v4_do_rcv); |
1da177e4 | 1505 | |
7487449c | 1506 | int tcp_v4_early_demux(struct sk_buff *skb) |
41063e9d | 1507 | { |
41063e9d DM |
1508 | const struct iphdr *iph; |
1509 | const struct tcphdr *th; | |
1510 | struct sock *sk; | |
41063e9d | 1511 | |
41063e9d | 1512 | if (skb->pkt_type != PACKET_HOST) |
7487449c | 1513 | return 0; |
41063e9d | 1514 | |
45f00f99 | 1515 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) |
7487449c | 1516 | return 0; |
41063e9d DM |
1517 | |
1518 | iph = ip_hdr(skb); | |
45f00f99 | 1519 | th = tcp_hdr(skb); |
41063e9d DM |
1520 | |
1521 | if (th->doff < sizeof(struct tcphdr) / 4) | |
7487449c | 1522 | return 0; |
41063e9d | 1523 | |
45f00f99 | 1524 | sk = __inet_lookup_established(dev_net(skb->dev), &tcp_hashinfo, |
41063e9d | 1525 | iph->saddr, th->source, |
7011d085 | 1526 | iph->daddr, ntohs(th->dest), |
3fa6f616 | 1527 | skb->skb_iif, inet_sdif(skb)); |
41063e9d DM |
1528 | if (sk) { |
1529 | skb->sk = sk; | |
1530 | skb->destructor = sock_edemux; | |
f7e4eb03 | 1531 | if (sk_fullsock(sk)) { |
d0c294c5 | 1532 | struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); |
505fbcf0 | 1533 | |
41063e9d DM |
1534 | if (dst) |
1535 | dst = dst_check(dst, 0); | |
92101b3b | 1536 | if (dst && |
505fbcf0 | 1537 | inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) |
92101b3b | 1538 | skb_dst_set_noref(skb, dst); |
41063e9d DM |
1539 | } |
1540 | } | |
7487449c | 1541 | return 0; |
41063e9d DM |
1542 | } |
1543 | ||
c9c33212 ED |
1544 | bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) |
1545 | { | |
1546 | u32 limit = sk->sk_rcvbuf + sk->sk_sndbuf; | |
1547 | ||
1548 | /* Only socket owner can try to collapse/prune rx queues | |
1549 | * to reduce memory overhead, so add a little headroom here. | |
1550 | * Few sockets backlog are possibly concurrently non empty. | |
1551 | */ | |
1552 | limit += 64*1024; | |
1553 | ||
1554 | /* In case all data was pulled from skb frags (in __pskb_pull_tail()), | |
1555 | * we can fix skb->truesize to its real value to avoid future drops. | |
1556 | * This is valid because skb is not yet charged to the socket. | |
1557 | * It has been noticed pure SACK packets were sometimes dropped | |
1558 | * (if cooked by drivers without copybreak feature). | |
1559 | */ | |
60b1af33 | 1560 | skb_condense(skb); |
c9c33212 ED |
1561 | |
1562 | if (unlikely(sk_add_backlog(sk, skb, limit))) { | |
1563 | bh_unlock_sock(sk); | |
1564 | __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPBACKLOGDROP); | |
1565 | return true; | |
1566 | } | |
1567 | return false; | |
1568 | } | |
1569 | EXPORT_SYMBOL(tcp_add_backlog); | |
1570 | ||
ac6e7800 ED |
1571 | int tcp_filter(struct sock *sk, struct sk_buff *skb) |
1572 | { | |
1573 | struct tcphdr *th = (struct tcphdr *)skb->data; | |
1574 | unsigned int eaten = skb->len; | |
1575 | int err; | |
1576 | ||
1577 | err = sk_filter_trim_cap(sk, skb, th->doff * 4); | |
1578 | if (!err) { | |
1579 | eaten -= skb->len; | |
1580 | TCP_SKB_CB(skb)->end_seq -= eaten; | |
1581 | } | |
1582 | return err; | |
1583 | } | |
1584 | EXPORT_SYMBOL(tcp_filter); | |
1585 | ||
1da177e4 LT |
1586 | /* |
1587 | * From tcp_input.c | |
1588 | */ | |
1589 | ||
1590 | int tcp_v4_rcv(struct sk_buff *skb) | |
1591 | { | |
3b24d854 | 1592 | struct net *net = dev_net(skb->dev); |
3fa6f616 | 1593 | int sdif = inet_sdif(skb); |
eddc9ec5 | 1594 | const struct iphdr *iph; |
cf533ea5 | 1595 | const struct tcphdr *th; |
3b24d854 | 1596 | bool refcounted; |
1da177e4 LT |
1597 | struct sock *sk; |
1598 | int ret; | |
1599 | ||
1600 | if (skb->pkt_type != PACKET_HOST) | |
1601 | goto discard_it; | |
1602 | ||
1603 | /* Count it even if it's bad */ | |
90bbcc60 | 1604 | __TCP_INC_STATS(net, TCP_MIB_INSEGS); |
1da177e4 LT |
1605 | |
1606 | if (!pskb_may_pull(skb, sizeof(struct tcphdr))) | |
1607 | goto discard_it; | |
1608 | ||
ea1627c2 | 1609 | th = (const struct tcphdr *)skb->data; |
1da177e4 | 1610 | |
ea1627c2 | 1611 | if (unlikely(th->doff < sizeof(struct tcphdr) / 4)) |
1da177e4 LT |
1612 | goto bad_packet; |
1613 | if (!pskb_may_pull(skb, th->doff * 4)) | |
1614 | goto discard_it; | |
1615 | ||
1616 | /* An explanation is required here, I think. | |
1617 | * Packet length and doff are validated by header prediction, | |
caa20d9a | 1618 | * provided case of th->doff==0 is eliminated. |
1da177e4 | 1619 | * So, we defer the checks. */ |
ed70fcfc TH |
1620 | |
1621 | if (skb_checksum_init(skb, IPPROTO_TCP, inet_compute_pseudo)) | |
6a5dc9e5 | 1622 | goto csum_error; |
1da177e4 | 1623 | |
ea1627c2 | 1624 | th = (const struct tcphdr *)skb->data; |
eddc9ec5 | 1625 | iph = ip_hdr(skb); |
971f10ec ED |
1626 | /* This is tricky : We move IPCB at its correct location into TCP_SKB_CB() |
1627 | * barrier() makes sure compiler wont play fool^Waliasing games. | |
1628 | */ | |
1629 | memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb), | |
1630 | sizeof(struct inet_skb_parm)); | |
1631 | barrier(); | |
1632 | ||
1da177e4 LT |
1633 | TCP_SKB_CB(skb)->seq = ntohl(th->seq); |
1634 | TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + | |
1635 | skb->len - th->doff * 4); | |
1636 | TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); | |
e11ecddf | 1637 | TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); |
04317daf | 1638 | TCP_SKB_CB(skb)->tcp_tw_isn = 0; |
b82d1bb4 | 1639 | TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph); |
1da177e4 | 1640 | TCP_SKB_CB(skb)->sacked = 0; |
98aaa913 MM |
1641 | TCP_SKB_CB(skb)->has_rxtstamp = |
1642 | skb->tstamp || skb_hwtstamps(skb)->hwtstamp; | |
1da177e4 | 1643 | |
4bdc3d66 | 1644 | lookup: |
a583636a | 1645 | sk = __inet_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th), th->source, |
3fa6f616 | 1646 | th->dest, sdif, &refcounted); |
1da177e4 LT |
1647 | if (!sk) |
1648 | goto no_tcp_socket; | |
1649 | ||
bb134d5d ED |
1650 | process: |
1651 | if (sk->sk_state == TCP_TIME_WAIT) | |
1652 | goto do_time_wait; | |
1653 | ||
079096f1 ED |
1654 | if (sk->sk_state == TCP_NEW_SYN_RECV) { |
1655 | struct request_sock *req = inet_reqsk(sk); | |
7716682c | 1656 | struct sock *nsk; |
079096f1 ED |
1657 | |
1658 | sk = req->rsk_listener; | |
72923555 | 1659 | if (unlikely(tcp_v4_inbound_md5_hash(sk, skb))) { |
e65c332d | 1660 | sk_drops_add(sk, skb); |
72923555 ED |
1661 | reqsk_put(req); |
1662 | goto discard_it; | |
1663 | } | |
7716682c | 1664 | if (unlikely(sk->sk_state != TCP_LISTEN)) { |
f03f2e15 | 1665 | inet_csk_reqsk_queue_drop_and_put(sk, req); |
4bdc3d66 ED |
1666 | goto lookup; |
1667 | } | |
3b24d854 ED |
1668 | /* We own a reference on the listener, increase it again |
1669 | * as we might lose it too soon. | |
1670 | */ | |
7716682c | 1671 | sock_hold(sk); |
3b24d854 | 1672 | refcounted = true; |
1f3b359f ED |
1673 | nsk = NULL; |
1674 | if (!tcp_filter(sk, skb)) | |
1675 | nsk = tcp_check_req(sk, skb, req, false); | |
079096f1 ED |
1676 | if (!nsk) { |
1677 | reqsk_put(req); | |
7716682c | 1678 | goto discard_and_relse; |
079096f1 ED |
1679 | } |
1680 | if (nsk == sk) { | |
079096f1 ED |
1681 | reqsk_put(req); |
1682 | } else if (tcp_child_process(sk, nsk, skb)) { | |
1683 | tcp_v4_send_reset(nsk, skb); | |
7716682c | 1684 | goto discard_and_relse; |
079096f1 | 1685 | } else { |
7716682c | 1686 | sock_put(sk); |
079096f1 ED |
1687 | return 0; |
1688 | } | |
1689 | } | |
6cce09f8 | 1690 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
02a1d6e7 | 1691 | __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP); |
d218d111 | 1692 | goto discard_and_relse; |
6cce09f8 | 1693 | } |
d218d111 | 1694 | |
1da177e4 LT |
1695 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
1696 | goto discard_and_relse; | |
9ea88a15 | 1697 | |
9ea88a15 DP |
1698 | if (tcp_v4_inbound_md5_hash(sk, skb)) |
1699 | goto discard_and_relse; | |
9ea88a15 | 1700 | |
b59c2701 | 1701 | nf_reset(skb); |
1da177e4 | 1702 | |
ac6e7800 | 1703 | if (tcp_filter(sk, skb)) |
1da177e4 | 1704 | goto discard_and_relse; |
ac6e7800 ED |
1705 | th = (const struct tcphdr *)skb->data; |
1706 | iph = ip_hdr(skb); | |
1da177e4 LT |
1707 | |
1708 | skb->dev = NULL; | |
1709 | ||
e994b2f0 ED |
1710 | if (sk->sk_state == TCP_LISTEN) { |
1711 | ret = tcp_v4_do_rcv(sk, skb); | |
1712 | goto put_and_return; | |
1713 | } | |
1714 | ||
1715 | sk_incoming_cpu_update(sk); | |
1716 | ||
c6366184 | 1717 | bh_lock_sock_nested(sk); |
a44d6eac | 1718 | tcp_segs_in(tcp_sk(sk), skb); |
1da177e4 LT |
1719 | ret = 0; |
1720 | if (!sock_owned_by_user(sk)) { | |
e7942d06 | 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, |
3fa6f616 DA |
1774 | inet_iif(skb), |
1775 | sdif); | |
1da177e4 | 1776 | if (sk2) { |
dbe7faa4 | 1777 | inet_twsk_deschedule_put(inet_twsk(sk)); |
1da177e4 | 1778 | sk = sk2; |
3b24d854 | 1779 | refcounted = false; |
1da177e4 LT |
1780 | goto process; |
1781 | } | |
1782 | /* Fall through to ACK */ | |
1783 | } | |
1784 | case TCP_TW_ACK: | |
1785 | tcp_v4_timewait_ack(sk, skb); | |
1786 | break; | |
1787 | case TCP_TW_RST: | |
271c3b9b FW |
1788 | tcp_v4_send_reset(sk, skb); |
1789 | inet_twsk_deschedule_put(inet_twsk(sk)); | |
1790 | goto discard_it; | |
1da177e4 LT |
1791 | case TCP_TW_SUCCESS:; |
1792 | } | |
1793 | goto discard_it; | |
1794 | } | |
1795 | ||
ccb7c410 DM |
1796 | static struct timewait_sock_ops tcp_timewait_sock_ops = { |
1797 | .twsk_obj_size = sizeof(struct tcp_timewait_sock), | |
1798 | .twsk_unique = tcp_twsk_unique, | |
1799 | .twsk_destructor= tcp_twsk_destructor, | |
ccb7c410 | 1800 | }; |
1da177e4 | 1801 | |
63d02d15 | 1802 | void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb) |
5d299f3d ED |
1803 | { |
1804 | struct dst_entry *dst = skb_dst(skb); | |
1805 | ||
5037e9ef | 1806 | if (dst && dst_hold_safe(dst)) { |
ca777eff ED |
1807 | sk->sk_rx_dst = dst; |
1808 | inet_sk(sk)->rx_dst_ifindex = skb->skb_iif; | |
1809 | } | |
5d299f3d | 1810 | } |
63d02d15 | 1811 | EXPORT_SYMBOL(inet_sk_rx_dst_set); |
5d299f3d | 1812 | |
3b401a81 | 1813 | const struct inet_connection_sock_af_ops ipv4_specific = { |
543d9cfe ACM |
1814 | .queue_xmit = ip_queue_xmit, |
1815 | .send_check = tcp_v4_send_check, | |
1816 | .rebuild_header = inet_sk_rebuild_header, | |
5d299f3d | 1817 | .sk_rx_dst_set = inet_sk_rx_dst_set, |
543d9cfe ACM |
1818 | .conn_request = tcp_v4_conn_request, |
1819 | .syn_recv_sock = tcp_v4_syn_recv_sock, | |
543d9cfe ACM |
1820 | .net_header_len = sizeof(struct iphdr), |
1821 | .setsockopt = ip_setsockopt, | |
1822 | .getsockopt = ip_getsockopt, | |
1823 | .addr2sockaddr = inet_csk_addr2sockaddr, | |
1824 | .sockaddr_len = sizeof(struct sockaddr_in), | |
3fdadf7d | 1825 | #ifdef CONFIG_COMPAT |
543d9cfe ACM |
1826 | .compat_setsockopt = compat_ip_setsockopt, |
1827 | .compat_getsockopt = compat_ip_getsockopt, | |
3fdadf7d | 1828 | #endif |
4fab9071 | 1829 | .mtu_reduced = tcp_v4_mtu_reduced, |
1da177e4 | 1830 | }; |
4bc2f18b | 1831 | EXPORT_SYMBOL(ipv4_specific); |
1da177e4 | 1832 | |
cfb6eeb4 | 1833 | #ifdef CONFIG_TCP_MD5SIG |
b2e4b3de | 1834 | static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = { |
cfb6eeb4 | 1835 | .md5_lookup = tcp_v4_md5_lookup, |
49a72dfb | 1836 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
cfb6eeb4 | 1837 | .md5_parse = tcp_v4_parse_md5_keys, |
cfb6eeb4 | 1838 | }; |
b6332e6c | 1839 | #endif |
cfb6eeb4 | 1840 | |
1da177e4 LT |
1841 | /* NOTE: A lot of things set to zero explicitly by call to |
1842 | * sk_alloc() so need not be done here. | |
1843 | */ | |
1844 | static int tcp_v4_init_sock(struct sock *sk) | |
1845 | { | |
6687e988 | 1846 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 | 1847 | |
900f65d3 | 1848 | tcp_init_sock(sk); |
1da177e4 | 1849 | |
8292a17a | 1850 | icsk->icsk_af_ops = &ipv4_specific; |
900f65d3 | 1851 | |
cfb6eeb4 | 1852 | #ifdef CONFIG_TCP_MD5SIG |
ac807fa8 | 1853 | tcp_sk(sk)->af_specific = &tcp_sock_ipv4_specific; |
cfb6eeb4 | 1854 | #endif |
1da177e4 | 1855 | |
1da177e4 LT |
1856 | return 0; |
1857 | } | |
1858 | ||
7d06b2e0 | 1859 | void tcp_v4_destroy_sock(struct sock *sk) |
1da177e4 LT |
1860 | { |
1861 | struct tcp_sock *tp = tcp_sk(sk); | |
1862 | ||
1863 | tcp_clear_xmit_timers(sk); | |
1864 | ||
6687e988 | 1865 | tcp_cleanup_congestion_control(sk); |
317a76f9 | 1866 | |
734942cc DW |
1867 | tcp_cleanup_ulp(sk); |
1868 | ||
1da177e4 | 1869 | /* Cleanup up the write buffer. */ |
fe067e8a | 1870 | tcp_write_queue_purge(sk); |
1da177e4 | 1871 | |
cf1ef3f0 WW |
1872 | /* Check if we want to disable active TFO */ |
1873 | tcp_fastopen_active_disable_ofo_check(sk); | |
1874 | ||
1da177e4 | 1875 | /* Cleans up our, hopefully empty, out_of_order_queue. */ |
9f5afeae | 1876 | skb_rbtree_purge(&tp->out_of_order_queue); |
1da177e4 | 1877 | |
cfb6eeb4 YH |
1878 | #ifdef CONFIG_TCP_MD5SIG |
1879 | /* Clean up the MD5 key list, if any */ | |
1880 | if (tp->md5sig_info) { | |
a915da9b | 1881 | tcp_clear_md5_list(sk); |
a8afca03 | 1882 | kfree_rcu(tp->md5sig_info, rcu); |
cfb6eeb4 YH |
1883 | tp->md5sig_info = NULL; |
1884 | } | |
1885 | #endif | |
1a2449a8 | 1886 | |
1da177e4 | 1887 | /* Clean up a referenced TCP bind bucket. */ |
463c84b9 | 1888 | if (inet_csk(sk)->icsk_bind_hash) |
ab1e0a13 | 1889 | inet_put_port(sk); |
1da177e4 | 1890 | |
00db4124 | 1891 | BUG_ON(tp->fastopen_rsk); |
435cf559 | 1892 | |
cf60af03 YC |
1893 | /* If socket is aborted during connect operation */ |
1894 | tcp_free_fastopen_req(tp); | |
cd8ae852 | 1895 | tcp_saved_syn_free(tp); |
cf60af03 | 1896 | |
180d8cd9 | 1897 | sk_sockets_allocated_dec(sk); |
1da177e4 | 1898 | } |
1da177e4 LT |
1899 | EXPORT_SYMBOL(tcp_v4_destroy_sock); |
1900 | ||
1901 | #ifdef CONFIG_PROC_FS | |
1902 | /* Proc filesystem TCP sock list dumping. */ | |
1903 | ||
a8b690f9 TH |
1904 | /* |
1905 | * Get next listener socket follow cur. If cur is NULL, get first socket | |
1906 | * starting from bucket given in st->bucket; when st->bucket is zero the | |
1907 | * very first socket in the hash table is returned. | |
1908 | */ | |
1da177e4 LT |
1909 | static void *listening_get_next(struct seq_file *seq, void *cur) |
1910 | { | |
5799de0b | 1911 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 1912 | struct net *net = seq_file_net(seq); |
3b24d854 | 1913 | struct inet_listen_hashbucket *ilb; |
3b24d854 | 1914 | struct sock *sk = cur; |
1da177e4 LT |
1915 | |
1916 | if (!sk) { | |
3b24d854 | 1917 | get_head: |
a8b690f9 | 1918 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
9652dc2e | 1919 | spin_lock(&ilb->lock); |
3b24d854 | 1920 | sk = sk_head(&ilb->head); |
a8b690f9 | 1921 | st->offset = 0; |
1da177e4 LT |
1922 | goto get_sk; |
1923 | } | |
5caea4ea | 1924 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
1da177e4 | 1925 | ++st->num; |
a8b690f9 | 1926 | ++st->offset; |
1da177e4 | 1927 | |
3b24d854 | 1928 | sk = sk_next(sk); |
1da177e4 | 1929 | get_sk: |
3b24d854 | 1930 | sk_for_each_from(sk) { |
8475ef9f PE |
1931 | if (!net_eq(sock_net(sk), net)) |
1932 | continue; | |
3b24d854 ED |
1933 | if (sk->sk_family == st->family) |
1934 | return sk; | |
1da177e4 | 1935 | } |
9652dc2e | 1936 | spin_unlock(&ilb->lock); |
a8b690f9 | 1937 | st->offset = 0; |
3b24d854 ED |
1938 | if (++st->bucket < INET_LHTABLE_SIZE) |
1939 | goto get_head; | |
1940 | return NULL; | |
1da177e4 LT |
1941 | } |
1942 | ||
1943 | static void *listening_get_idx(struct seq_file *seq, loff_t *pos) | |
1944 | { | |
a8b690f9 TH |
1945 | struct tcp_iter_state *st = seq->private; |
1946 | void *rc; | |
1947 | ||
1948 | st->bucket = 0; | |
1949 | st->offset = 0; | |
1950 | rc = listening_get_next(seq, NULL); | |
1da177e4 LT |
1951 | |
1952 | while (rc && *pos) { | |
1953 | rc = listening_get_next(seq, rc); | |
1954 | --*pos; | |
1955 | } | |
1956 | return rc; | |
1957 | } | |
1958 | ||
05dbc7b5 | 1959 | static inline bool empty_bucket(const struct tcp_iter_state *st) |
6eac5604 | 1960 | { |
05dbc7b5 | 1961 | return hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].chain); |
6eac5604 AK |
1962 | } |
1963 | ||
a8b690f9 TH |
1964 | /* |
1965 | * Get first established socket starting from bucket given in st->bucket. | |
1966 | * If st->bucket is zero, the very first socket in the hash is returned. | |
1967 | */ | |
1da177e4 LT |
1968 | static void *established_get_first(struct seq_file *seq) |
1969 | { | |
5799de0b | 1970 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 1971 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
1972 | void *rc = NULL; |
1973 | ||
a8b690f9 TH |
1974 | st->offset = 0; |
1975 | for (; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) { | |
1da177e4 | 1976 | struct sock *sk; |
3ab5aee7 | 1977 | struct hlist_nulls_node *node; |
9db66bdc | 1978 | spinlock_t *lock = inet_ehash_lockp(&tcp_hashinfo, st->bucket); |
1da177e4 | 1979 | |
6eac5604 AK |
1980 | /* Lockless fast path for the common case of empty buckets */ |
1981 | if (empty_bucket(st)) | |
1982 | continue; | |
1983 | ||
9db66bdc | 1984 | spin_lock_bh(lock); |
3ab5aee7 | 1985 | sk_nulls_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) { |
f40c8174 | 1986 | if (sk->sk_family != st->family || |
878628fb | 1987 | !net_eq(sock_net(sk), net)) { |
1da177e4 LT |
1988 | continue; |
1989 | } | |
1990 | rc = sk; | |
1991 | goto out; | |
1992 | } | |
9db66bdc | 1993 | spin_unlock_bh(lock); |
1da177e4 LT |
1994 | } |
1995 | out: | |
1996 | return rc; | |
1997 | } | |
1998 | ||
1999 | static void *established_get_next(struct seq_file *seq, void *cur) | |
2000 | { | |
2001 | struct sock *sk = cur; | |
3ab5aee7 | 2002 | struct hlist_nulls_node *node; |
5799de0b | 2003 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2004 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2005 | |
2006 | ++st->num; | |
a8b690f9 | 2007 | ++st->offset; |
1da177e4 | 2008 | |
05dbc7b5 | 2009 | sk = sk_nulls_next(sk); |
1da177e4 | 2010 | |
3ab5aee7 | 2011 | sk_nulls_for_each_from(sk, node) { |
878628fb | 2012 | if (sk->sk_family == st->family && net_eq(sock_net(sk), net)) |
05dbc7b5 | 2013 | return sk; |
1da177e4 LT |
2014 | } |
2015 | ||
05dbc7b5 ED |
2016 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
2017 | ++st->bucket; | |
2018 | return established_get_first(seq); | |
1da177e4 LT |
2019 | } |
2020 | ||
2021 | static void *established_get_idx(struct seq_file *seq, loff_t pos) | |
2022 | { | |
a8b690f9 TH |
2023 | struct tcp_iter_state *st = seq->private; |
2024 | void *rc; | |
2025 | ||
2026 | st->bucket = 0; | |
2027 | rc = established_get_first(seq); | |
1da177e4 LT |
2028 | |
2029 | while (rc && pos) { | |
2030 | rc = established_get_next(seq, rc); | |
2031 | --pos; | |
7174259e | 2032 | } |
1da177e4 LT |
2033 | return rc; |
2034 | } | |
2035 | ||
2036 | static void *tcp_get_idx(struct seq_file *seq, loff_t pos) | |
2037 | { | |
2038 | void *rc; | |
5799de0b | 2039 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2040 | |
1da177e4 LT |
2041 | st->state = TCP_SEQ_STATE_LISTENING; |
2042 | rc = listening_get_idx(seq, &pos); | |
2043 | ||
2044 | if (!rc) { | |
1da177e4 LT |
2045 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2046 | rc = established_get_idx(seq, pos); | |
2047 | } | |
2048 | ||
2049 | return rc; | |
2050 | } | |
2051 | ||
a8b690f9 TH |
2052 | static void *tcp_seek_last_pos(struct seq_file *seq) |
2053 | { | |
2054 | struct tcp_iter_state *st = seq->private; | |
2055 | int offset = st->offset; | |
2056 | int orig_num = st->num; | |
2057 | void *rc = NULL; | |
2058 | ||
2059 | switch (st->state) { | |
a8b690f9 TH |
2060 | case TCP_SEQ_STATE_LISTENING: |
2061 | if (st->bucket >= INET_LHTABLE_SIZE) | |
2062 | break; | |
2063 | st->state = TCP_SEQ_STATE_LISTENING; | |
2064 | rc = listening_get_next(seq, NULL); | |
2065 | while (offset-- && rc) | |
2066 | rc = listening_get_next(seq, rc); | |
2067 | if (rc) | |
2068 | break; | |
2069 | st->bucket = 0; | |
05dbc7b5 | 2070 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
a8b690f9 TH |
2071 | /* Fallthrough */ |
2072 | case TCP_SEQ_STATE_ESTABLISHED: | |
a8b690f9 TH |
2073 | if (st->bucket > tcp_hashinfo.ehash_mask) |
2074 | break; | |
2075 | rc = established_get_first(seq); | |
2076 | while (offset-- && rc) | |
2077 | rc = established_get_next(seq, rc); | |
2078 | } | |
2079 | ||
2080 | st->num = orig_num; | |
2081 | ||
2082 | return rc; | |
2083 | } | |
2084 | ||
1da177e4 LT |
2085 | static void *tcp_seq_start(struct seq_file *seq, loff_t *pos) |
2086 | { | |
5799de0b | 2087 | struct tcp_iter_state *st = seq->private; |
a8b690f9 TH |
2088 | void *rc; |
2089 | ||
2090 | if (*pos && *pos == st->last_pos) { | |
2091 | rc = tcp_seek_last_pos(seq); | |
2092 | if (rc) | |
2093 | goto out; | |
2094 | } | |
2095 | ||
1da177e4 LT |
2096 | st->state = TCP_SEQ_STATE_LISTENING; |
2097 | st->num = 0; | |
a8b690f9 TH |
2098 | st->bucket = 0; |
2099 | st->offset = 0; | |
2100 | rc = *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
2101 | ||
2102 | out: | |
2103 | st->last_pos = *pos; | |
2104 | return rc; | |
1da177e4 LT |
2105 | } |
2106 | ||
2107 | static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2108 | { | |
a8b690f9 | 2109 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2110 | void *rc = NULL; |
1da177e4 LT |
2111 | |
2112 | if (v == SEQ_START_TOKEN) { | |
2113 | rc = tcp_get_idx(seq, 0); | |
2114 | goto out; | |
2115 | } | |
1da177e4 LT |
2116 | |
2117 | switch (st->state) { | |
1da177e4 LT |
2118 | case TCP_SEQ_STATE_LISTENING: |
2119 | rc = listening_get_next(seq, v); | |
2120 | if (!rc) { | |
1da177e4 | 2121 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
a8b690f9 TH |
2122 | st->bucket = 0; |
2123 | st->offset = 0; | |
1da177e4 LT |
2124 | rc = established_get_first(seq); |
2125 | } | |
2126 | break; | |
2127 | case TCP_SEQ_STATE_ESTABLISHED: | |
1da177e4 LT |
2128 | rc = established_get_next(seq, v); |
2129 | break; | |
2130 | } | |
2131 | out: | |
2132 | ++*pos; | |
a8b690f9 | 2133 | st->last_pos = *pos; |
1da177e4 LT |
2134 | return rc; |
2135 | } | |
2136 | ||
2137 | static void tcp_seq_stop(struct seq_file *seq, void *v) | |
2138 | { | |
5799de0b | 2139 | struct tcp_iter_state *st = seq->private; |
1da177e4 LT |
2140 | |
2141 | switch (st->state) { | |
1da177e4 LT |
2142 | case TCP_SEQ_STATE_LISTENING: |
2143 | if (v != SEQ_START_TOKEN) | |
9652dc2e | 2144 | spin_unlock(&tcp_hashinfo.listening_hash[st->bucket].lock); |
1da177e4 | 2145 | break; |
1da177e4 LT |
2146 | case TCP_SEQ_STATE_ESTABLISHED: |
2147 | if (v) | |
9db66bdc | 2148 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
1da177e4 LT |
2149 | break; |
2150 | } | |
2151 | } | |
2152 | ||
73cb88ec | 2153 | int tcp_seq_open(struct inode *inode, struct file *file) |
1da177e4 | 2154 | { |
d9dda78b | 2155 | struct tcp_seq_afinfo *afinfo = PDE_DATA(inode); |
1da177e4 | 2156 | struct tcp_iter_state *s; |
52d6f3f1 | 2157 | int err; |
1da177e4 | 2158 | |
52d6f3f1 DL |
2159 | err = seq_open_net(inode, file, &afinfo->seq_ops, |
2160 | sizeof(struct tcp_iter_state)); | |
2161 | if (err < 0) | |
2162 | return err; | |
f40c8174 | 2163 | |
52d6f3f1 | 2164 | s = ((struct seq_file *)file->private_data)->private; |
1da177e4 | 2165 | s->family = afinfo->family; |
688d1945 | 2166 | s->last_pos = 0; |
f40c8174 DL |
2167 | return 0; |
2168 | } | |
73cb88ec | 2169 | EXPORT_SYMBOL(tcp_seq_open); |
f40c8174 | 2170 | |
6f8b13bc | 2171 | int tcp_proc_register(struct net *net, struct tcp_seq_afinfo *afinfo) |
1da177e4 LT |
2172 | { |
2173 | int rc = 0; | |
2174 | struct proc_dir_entry *p; | |
2175 | ||
9427c4b3 DL |
2176 | afinfo->seq_ops.start = tcp_seq_start; |
2177 | afinfo->seq_ops.next = tcp_seq_next; | |
2178 | afinfo->seq_ops.stop = tcp_seq_stop; | |
2179 | ||
84841c3c | 2180 | p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net, |
73cb88ec | 2181 | afinfo->seq_fops, afinfo); |
84841c3c | 2182 | if (!p) |
1da177e4 LT |
2183 | rc = -ENOMEM; |
2184 | return rc; | |
2185 | } | |
4bc2f18b | 2186 | EXPORT_SYMBOL(tcp_proc_register); |
1da177e4 | 2187 | |
6f8b13bc | 2188 | void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo) |
1da177e4 | 2189 | { |
ece31ffd | 2190 | remove_proc_entry(afinfo->name, net->proc_net); |
1da177e4 | 2191 | } |
4bc2f18b | 2192 | EXPORT_SYMBOL(tcp_proc_unregister); |
1da177e4 | 2193 | |
d4f06873 | 2194 | static void get_openreq4(const struct request_sock *req, |
aa3a0c8c | 2195 | struct seq_file *f, int i) |
1da177e4 | 2196 | { |
2e6599cb | 2197 | const struct inet_request_sock *ireq = inet_rsk(req); |
fa76ce73 | 2198 | long delta = req->rsk_timer.expires - jiffies; |
1da177e4 | 2199 | |
5e659e4c | 2200 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
652586df | 2201 | " %02X %08X:%08X %02X:%08lX %08X %5u %8d %u %d %pK", |
1da177e4 | 2202 | i, |
634fb979 | 2203 | ireq->ir_loc_addr, |
d4f06873 | 2204 | ireq->ir_num, |
634fb979 ED |
2205 | ireq->ir_rmt_addr, |
2206 | ntohs(ireq->ir_rmt_port), | |
1da177e4 LT |
2207 | TCP_SYN_RECV, |
2208 | 0, 0, /* could print option size, but that is af dependent. */ | |
2209 | 1, /* timers active (only the expire timer) */ | |
a399a805 | 2210 | jiffies_delta_to_clock_t(delta), |
e6c022a4 | 2211 | req->num_timeout, |
aa3a0c8c ED |
2212 | from_kuid_munged(seq_user_ns(f), |
2213 | sock_i_uid(req->rsk_listener)), | |
1da177e4 LT |
2214 | 0, /* non standard timer */ |
2215 | 0, /* open_requests have no inode */ | |
d4f06873 | 2216 | 0, |
652586df | 2217 | req); |
1da177e4 LT |
2218 | } |
2219 | ||
652586df | 2220 | static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i) |
1da177e4 LT |
2221 | { |
2222 | int timer_active; | |
2223 | unsigned long timer_expires; | |
cf533ea5 | 2224 | const struct tcp_sock *tp = tcp_sk(sk); |
cf4c6bf8 | 2225 | const struct inet_connection_sock *icsk = inet_csk(sk); |
cf533ea5 | 2226 | const struct inet_sock *inet = inet_sk(sk); |
0536fcc0 | 2227 | const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; |
c720c7e8 ED |
2228 | __be32 dest = inet->inet_daddr; |
2229 | __be32 src = inet->inet_rcv_saddr; | |
2230 | __u16 destp = ntohs(inet->inet_dport); | |
2231 | __u16 srcp = ntohs(inet->inet_sport); | |
49d09007 | 2232 | int rx_queue; |
00fd38d9 | 2233 | int state; |
1da177e4 | 2234 | |
6ba8a3b1 | 2235 | if (icsk->icsk_pending == ICSK_TIME_RETRANS || |
57dde7f7 | 2236 | icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || |
6ba8a3b1 | 2237 | icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { |
1da177e4 | 2238 | timer_active = 1; |
463c84b9 ACM |
2239 | timer_expires = icsk->icsk_timeout; |
2240 | } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { | |
1da177e4 | 2241 | timer_active = 4; |
463c84b9 | 2242 | timer_expires = icsk->icsk_timeout; |
cf4c6bf8 | 2243 | } else if (timer_pending(&sk->sk_timer)) { |
1da177e4 | 2244 | timer_active = 2; |
cf4c6bf8 | 2245 | timer_expires = sk->sk_timer.expires; |
1da177e4 LT |
2246 | } else { |
2247 | timer_active = 0; | |
2248 | timer_expires = jiffies; | |
2249 | } | |
2250 | ||
00fd38d9 ED |
2251 | state = sk_state_load(sk); |
2252 | if (state == TCP_LISTEN) | |
49d09007 ED |
2253 | rx_queue = sk->sk_ack_backlog; |
2254 | else | |
00fd38d9 ED |
2255 | /* Because we don't lock the socket, |
2256 | * we might find a transient negative value. | |
49d09007 ED |
2257 | */ |
2258 | rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0); | |
2259 | ||
5e659e4c | 2260 | seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " |
652586df | 2261 | "%08X %5u %8d %lu %d %pK %lu %lu %u %u %d", |
00fd38d9 | 2262 | i, src, srcp, dest, destp, state, |
47da8ee6 | 2263 | tp->write_seq - tp->snd_una, |
49d09007 | 2264 | rx_queue, |
1da177e4 | 2265 | timer_active, |
a399a805 | 2266 | jiffies_delta_to_clock_t(timer_expires - jiffies), |
463c84b9 | 2267 | icsk->icsk_retransmits, |
a7cb5a49 | 2268 | from_kuid_munged(seq_user_ns(f), sock_i_uid(sk)), |
6687e988 | 2269 | icsk->icsk_probes_out, |
cf4c6bf8 | 2270 | sock_i_ino(sk), |
41c6d650 | 2271 | refcount_read(&sk->sk_refcnt), sk, |
7be87351 SH |
2272 | jiffies_to_clock_t(icsk->icsk_rto), |
2273 | jiffies_to_clock_t(icsk->icsk_ack.ato), | |
463c84b9 | 2274 | (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, |
1da177e4 | 2275 | tp->snd_cwnd, |
00fd38d9 ED |
2276 | state == TCP_LISTEN ? |
2277 | fastopenq->max_qlen : | |
652586df | 2278 | (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh)); |
1da177e4 LT |
2279 | } |
2280 | ||
cf533ea5 | 2281 | static void get_timewait4_sock(const struct inet_timewait_sock *tw, |
652586df | 2282 | struct seq_file *f, int i) |
1da177e4 | 2283 | { |
789f558c | 2284 | long delta = tw->tw_timer.expires - jiffies; |
23f33c2d | 2285 | __be32 dest, src; |
1da177e4 | 2286 | __u16 destp, srcp; |
1da177e4 LT |
2287 | |
2288 | dest = tw->tw_daddr; | |
2289 | src = tw->tw_rcv_saddr; | |
2290 | destp = ntohs(tw->tw_dport); | |
2291 | srcp = ntohs(tw->tw_sport); | |
2292 | ||
5e659e4c | 2293 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
652586df | 2294 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK", |
1da177e4 | 2295 | i, src, srcp, dest, destp, tw->tw_substate, 0, 0, |
a399a805 | 2296 | 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, |
41c6d650 | 2297 | refcount_read(&tw->tw_refcnt), tw); |
1da177e4 LT |
2298 | } |
2299 | ||
2300 | #define TMPSZ 150 | |
2301 | ||
2302 | static int tcp4_seq_show(struct seq_file *seq, void *v) | |
2303 | { | |
5799de0b | 2304 | struct tcp_iter_state *st; |
05dbc7b5 | 2305 | struct sock *sk = v; |
1da177e4 | 2306 | |
652586df | 2307 | seq_setwidth(seq, TMPSZ - 1); |
1da177e4 | 2308 | if (v == SEQ_START_TOKEN) { |
652586df | 2309 | seq_puts(seq, " sl local_address rem_address st tx_queue " |
1da177e4 LT |
2310 | "rx_queue tr tm->when retrnsmt uid timeout " |
2311 | "inode"); | |
2312 | goto out; | |
2313 | } | |
2314 | st = seq->private; | |
2315 | ||
079096f1 ED |
2316 | if (sk->sk_state == TCP_TIME_WAIT) |
2317 | get_timewait4_sock(v, seq, st->num); | |
2318 | else if (sk->sk_state == TCP_NEW_SYN_RECV) | |
aa3a0c8c | 2319 | get_openreq4(v, seq, st->num); |
079096f1 ED |
2320 | else |
2321 | get_tcp4_sock(v, seq, st->num); | |
1da177e4 | 2322 | out: |
652586df | 2323 | seq_pad(seq, '\n'); |
1da177e4 LT |
2324 | return 0; |
2325 | } | |
2326 | ||
73cb88ec AV |
2327 | static const struct file_operations tcp_afinfo_seq_fops = { |
2328 | .owner = THIS_MODULE, | |
2329 | .open = tcp_seq_open, | |
2330 | .read = seq_read, | |
2331 | .llseek = seq_lseek, | |
2332 | .release = seq_release_net | |
2333 | }; | |
2334 | ||
1da177e4 | 2335 | static struct tcp_seq_afinfo tcp4_seq_afinfo = { |
1da177e4 LT |
2336 | .name = "tcp", |
2337 | .family = AF_INET, | |
73cb88ec | 2338 | .seq_fops = &tcp_afinfo_seq_fops, |
9427c4b3 DL |
2339 | .seq_ops = { |
2340 | .show = tcp4_seq_show, | |
2341 | }, | |
1da177e4 LT |
2342 | }; |
2343 | ||
2c8c1e72 | 2344 | static int __net_init tcp4_proc_init_net(struct net *net) |
757764f6 PE |
2345 | { |
2346 | return tcp_proc_register(net, &tcp4_seq_afinfo); | |
2347 | } | |
2348 | ||
2c8c1e72 | 2349 | static void __net_exit tcp4_proc_exit_net(struct net *net) |
757764f6 PE |
2350 | { |
2351 | tcp_proc_unregister(net, &tcp4_seq_afinfo); | |
2352 | } | |
2353 | ||
2354 | static struct pernet_operations tcp4_net_ops = { | |
2355 | .init = tcp4_proc_init_net, | |
2356 | .exit = tcp4_proc_exit_net, | |
2357 | }; | |
2358 | ||
1da177e4 LT |
2359 | int __init tcp4_proc_init(void) |
2360 | { | |
757764f6 | 2361 | return register_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2362 | } |
2363 | ||
2364 | void tcp4_proc_exit(void) | |
2365 | { | |
757764f6 | 2366 | unregister_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2367 | } |
2368 | #endif /* CONFIG_PROC_FS */ | |
2369 | ||
2370 | struct proto tcp_prot = { | |
2371 | .name = "TCP", | |
2372 | .owner = THIS_MODULE, | |
2373 | .close = tcp_close, | |
2374 | .connect = tcp_v4_connect, | |
2375 | .disconnect = tcp_disconnect, | |
463c84b9 | 2376 | .accept = inet_csk_accept, |
1da177e4 LT |
2377 | .ioctl = tcp_ioctl, |
2378 | .init = tcp_v4_init_sock, | |
2379 | .destroy = tcp_v4_destroy_sock, | |
2380 | .shutdown = tcp_shutdown, | |
2381 | .setsockopt = tcp_setsockopt, | |
2382 | .getsockopt = tcp_getsockopt, | |
4b9d07a4 | 2383 | .keepalive = tcp_set_keepalive, |
1da177e4 | 2384 | .recvmsg = tcp_recvmsg, |
7ba42910 CG |
2385 | .sendmsg = tcp_sendmsg, |
2386 | .sendpage = tcp_sendpage, | |
1da177e4 | 2387 | .backlog_rcv = tcp_v4_do_rcv, |
46d3ceab | 2388 | .release_cb = tcp_release_cb, |
ab1e0a13 ACM |
2389 | .hash = inet_hash, |
2390 | .unhash = inet_unhash, | |
2391 | .get_port = inet_csk_get_port, | |
1da177e4 | 2392 | .enter_memory_pressure = tcp_enter_memory_pressure, |
06044751 | 2393 | .leave_memory_pressure = tcp_leave_memory_pressure, |
c9bee3b7 | 2394 | .stream_memory_free = tcp_stream_memory_free, |
1da177e4 | 2395 | .sockets_allocated = &tcp_sockets_allocated, |
0a5578cf | 2396 | .orphan_count = &tcp_orphan_count, |
1da177e4 LT |
2397 | .memory_allocated = &tcp_memory_allocated, |
2398 | .memory_pressure = &tcp_memory_pressure, | |
a4fe34bf | 2399 | .sysctl_mem = sysctl_tcp_mem, |
1da177e4 LT |
2400 | .sysctl_wmem = sysctl_tcp_wmem, |
2401 | .sysctl_rmem = sysctl_tcp_rmem, | |
2402 | .max_header = MAX_TCP_HEADER, | |
2403 | .obj_size = sizeof(struct tcp_sock), | |
5f0d5a3a | 2404 | .slab_flags = SLAB_TYPESAFE_BY_RCU, |
6d6ee43e | 2405 | .twsk_prot = &tcp_timewait_sock_ops, |
60236fdd | 2406 | .rsk_prot = &tcp_request_sock_ops, |
39d8cda7 | 2407 | .h.hashinfo = &tcp_hashinfo, |
7ba42910 | 2408 | .no_autobind = true, |
543d9cfe ACM |
2409 | #ifdef CONFIG_COMPAT |
2410 | .compat_setsockopt = compat_tcp_setsockopt, | |
2411 | .compat_getsockopt = compat_tcp_getsockopt, | |
d1a4c0b3 | 2412 | #endif |
c1e64e29 | 2413 | .diag_destroy = tcp_abort, |
1da177e4 | 2414 | }; |
4bc2f18b | 2415 | EXPORT_SYMBOL(tcp_prot); |
1da177e4 | 2416 | |
bdbbb852 ED |
2417 | static void __net_exit tcp_sk_exit(struct net *net) |
2418 | { | |
2419 | int cpu; | |
2420 | ||
2421 | for_each_possible_cpu(cpu) | |
2422 | inet_ctl_sock_destroy(*per_cpu_ptr(net->ipv4.tcp_sk, cpu)); | |
2423 | free_percpu(net->ipv4.tcp_sk); | |
2424 | } | |
2425 | ||
046ee902 DL |
2426 | static int __net_init tcp_sk_init(struct net *net) |
2427 | { | |
fee83d09 | 2428 | int res, cpu, cnt; |
bdbbb852 ED |
2429 | |
2430 | net->ipv4.tcp_sk = alloc_percpu(struct sock *); | |
2431 | if (!net->ipv4.tcp_sk) | |
2432 | return -ENOMEM; | |
2433 | ||
2434 | for_each_possible_cpu(cpu) { | |
2435 | struct sock *sk; | |
2436 | ||
2437 | res = inet_ctl_sock_create(&sk, PF_INET, SOCK_RAW, | |
2438 | IPPROTO_TCP, net); | |
2439 | if (res) | |
2440 | goto fail; | |
a9d6532b | 2441 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); |
bdbbb852 ED |
2442 | *per_cpu_ptr(net->ipv4.tcp_sk, cpu) = sk; |
2443 | } | |
49213555 | 2444 | |
5d134f1c | 2445 | net->ipv4.sysctl_tcp_ecn = 2; |
49213555 DB |
2446 | net->ipv4.sysctl_tcp_ecn_fallback = 1; |
2447 | ||
b0f9ca53 | 2448 | net->ipv4.sysctl_tcp_base_mss = TCP_BASE_MSS; |
6b58e0a5 | 2449 | net->ipv4.sysctl_tcp_probe_threshold = TCP_PROBE_THRESHOLD; |
05cbc0db | 2450 | net->ipv4.sysctl_tcp_probe_interval = TCP_PROBE_INTERVAL; |
046ee902 | 2451 | |
13b287e8 | 2452 | net->ipv4.sysctl_tcp_keepalive_time = TCP_KEEPALIVE_TIME; |
9bd6861b | 2453 | net->ipv4.sysctl_tcp_keepalive_probes = TCP_KEEPALIVE_PROBES; |
b840d15d | 2454 | net->ipv4.sysctl_tcp_keepalive_intvl = TCP_KEEPALIVE_INTVL; |
13b287e8 | 2455 | |
6fa25166 | 2456 | net->ipv4.sysctl_tcp_syn_retries = TCP_SYN_RETRIES; |
7c083ecb | 2457 | net->ipv4.sysctl_tcp_synack_retries = TCP_SYNACK_RETRIES; |
0aca737d | 2458 | net->ipv4.sysctl_tcp_syncookies = 1; |
1043e25f | 2459 | net->ipv4.sysctl_tcp_reordering = TCP_FASTRETRANS_THRESH; |
ae5c3f40 | 2460 | net->ipv4.sysctl_tcp_retries1 = TCP_RETR1; |
c6214a97 | 2461 | net->ipv4.sysctl_tcp_retries2 = TCP_RETR2; |
c402d9be | 2462 | net->ipv4.sysctl_tcp_orphan_retries = 0; |
1e579caa | 2463 | net->ipv4.sysctl_tcp_fin_timeout = TCP_FIN_TIMEOUT; |
4979f2d9 | 2464 | net->ipv4.sysctl_tcp_notsent_lowat = UINT_MAX; |
56ab6b93 | 2465 | net->ipv4.sysctl_tcp_tw_reuse = 0; |
12ed8244 | 2466 | |
fee83d09 | 2467 | cnt = tcp_hashinfo.ehash_mask + 1; |
fee83d09 | 2468 | net->ipv4.tcp_death_row.sysctl_max_tw_buckets = (cnt + 1) / 2; |
1946e672 HY |
2469 | net->ipv4.tcp_death_row.hashinfo = &tcp_hashinfo; |
2470 | ||
fee83d09 | 2471 | net->ipv4.sysctl_max_syn_backlog = max(128, cnt / 256); |
f9301034 | 2472 | net->ipv4.sysctl_tcp_sack = 1; |
9bb37ef0 | 2473 | net->ipv4.sysctl_tcp_window_scaling = 1; |
5d2ed052 | 2474 | net->ipv4.sysctl_tcp_timestamps = 1; |
fee83d09 | 2475 | |
e1cfcbe8 | 2476 | net->ipv4.sysctl_tcp_fastopen = TFO_CLIENT_ENABLE; |
43713848 | 2477 | spin_lock_init(&net->ipv4.tcp_fastopen_ctx_lock); |
3733be14 HY |
2478 | net->ipv4.sysctl_tcp_fastopen_blackhole_timeout = 60 * 60; |
2479 | atomic_set(&net->ipv4.tfo_active_disable_times, 0); | |
e1cfcbe8 | 2480 | |
49213555 | 2481 | return 0; |
bdbbb852 ED |
2482 | fail: |
2483 | tcp_sk_exit(net); | |
2484 | ||
2485 | return res; | |
b099ce26 EB |
2486 | } |
2487 | ||
2488 | static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list) | |
2489 | { | |
43713848 HY |
2490 | struct net *net; |
2491 | ||
1946e672 | 2492 | inet_twsk_purge(&tcp_hashinfo, AF_INET); |
43713848 HY |
2493 | |
2494 | list_for_each_entry(net, net_exit_list, exit_list) | |
2495 | tcp_fastopen_ctx_destroy(net); | |
046ee902 DL |
2496 | } |
2497 | ||
2498 | static struct pernet_operations __net_initdata tcp_sk_ops = { | |
b099ce26 EB |
2499 | .init = tcp_sk_init, |
2500 | .exit = tcp_sk_exit, | |
2501 | .exit_batch = tcp_sk_exit_batch, | |
046ee902 DL |
2502 | }; |
2503 | ||
9b0f976f | 2504 | void __init tcp_v4_init(void) |
1da177e4 | 2505 | { |
6a1b3054 | 2506 | if (register_pernet_subsys(&tcp_sk_ops)) |
1da177e4 | 2507 | panic("Failed to create the TCP control socket.\n"); |
1da177e4 | 2508 | } |