Commit | Line | Data |
---|---|---|
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> |
1a2449a8 | 75 | #include <net/netdma.h> |
6e5714ea | 76 | #include <net/secure_seq.h> |
d1a4c0b3 | 77 | #include <net/tcp_memcontrol.h> |
1da177e4 LT |
78 | |
79 | #include <linux/inet.h> | |
80 | #include <linux/ipv6.h> | |
81 | #include <linux/stddef.h> | |
82 | #include <linux/proc_fs.h> | |
83 | #include <linux/seq_file.h> | |
84 | ||
cfb6eeb4 YH |
85 | #include <linux/crypto.h> |
86 | #include <linux/scatterlist.h> | |
87 | ||
ab32ea5d BH |
88 | int sysctl_tcp_tw_reuse __read_mostly; |
89 | int sysctl_tcp_low_latency __read_mostly; | |
4bc2f18b | 90 | EXPORT_SYMBOL(sysctl_tcp_low_latency); |
1da177e4 | 91 | |
1da177e4 | 92 | |
cfb6eeb4 | 93 | #ifdef CONFIG_TCP_MD5SIG |
a915da9b | 94 | static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, |
318cf7aa | 95 | __be32 daddr, __be32 saddr, const struct tcphdr *th); |
cfb6eeb4 YH |
96 | #endif |
97 | ||
5caea4ea | 98 | struct inet_hashinfo tcp_hashinfo; |
4bc2f18b | 99 | EXPORT_SYMBOL(tcp_hashinfo); |
1da177e4 | 100 | |
cf533ea5 | 101 | static inline __u32 tcp_v4_init_sequence(const struct sk_buff *skb) |
1da177e4 | 102 | { |
eddc9ec5 ACM |
103 | return secure_tcp_sequence_number(ip_hdr(skb)->daddr, |
104 | ip_hdr(skb)->saddr, | |
aa8223c7 ACM |
105 | tcp_hdr(skb)->dest, |
106 | tcp_hdr(skb)->source); | |
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 && | |
126 | (twp == NULL || (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 | ||
ee995283 PE |
141 | static int tcp_repair_connect(struct sock *sk) |
142 | { | |
143 | tcp_connect_init(sk); | |
144 | tcp_finish_connect(sk, NULL); | |
145 | ||
146 | return 0; | |
147 | } | |
148 | ||
1da177e4 LT |
149 | /* This will initiate an outgoing connection. */ |
150 | int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
151 | { | |
2d7192d6 | 152 | struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
1da177e4 LT |
153 | struct inet_sock *inet = inet_sk(sk); |
154 | struct tcp_sock *tp = tcp_sk(sk); | |
dca8b089 | 155 | __be16 orig_sport, orig_dport; |
bada8adc | 156 | __be32 daddr, nexthop; |
da905bd1 | 157 | struct flowi4 *fl4; |
2d7192d6 | 158 | struct rtable *rt; |
1da177e4 | 159 | int err; |
f6d8bd05 | 160 | struct ip_options_rcu *inet_opt; |
1da177e4 LT |
161 | |
162 | if (addr_len < sizeof(struct sockaddr_in)) | |
163 | return -EINVAL; | |
164 | ||
165 | if (usin->sin_family != AF_INET) | |
166 | return -EAFNOSUPPORT; | |
167 | ||
168 | nexthop = daddr = usin->sin_addr.s_addr; | |
f6d8bd05 ED |
169 | inet_opt = rcu_dereference_protected(inet->inet_opt, |
170 | sock_owned_by_user(sk)); | |
171 | if (inet_opt && inet_opt->opt.srr) { | |
1da177e4 LT |
172 | if (!daddr) |
173 | return -EINVAL; | |
f6d8bd05 | 174 | nexthop = inet_opt->opt.faddr; |
1da177e4 LT |
175 | } |
176 | ||
dca8b089 DM |
177 | orig_sport = inet->inet_sport; |
178 | orig_dport = usin->sin_port; | |
da905bd1 DM |
179 | fl4 = &inet->cork.fl.u.ip4; |
180 | rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, | |
b23dd4fe DM |
181 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, |
182 | IPPROTO_TCP, | |
183 | orig_sport, orig_dport, sk, true); | |
184 | if (IS_ERR(rt)) { | |
185 | err = PTR_ERR(rt); | |
186 | if (err == -ENETUNREACH) | |
7c73a6fa | 187 | IP_INC_STATS_BH(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); |
b23dd4fe | 188 | return err; |
584bdf8c | 189 | } |
1da177e4 LT |
190 | |
191 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { | |
192 | ip_rt_put(rt); | |
193 | return -ENETUNREACH; | |
194 | } | |
195 | ||
f6d8bd05 | 196 | if (!inet_opt || !inet_opt->opt.srr) |
da905bd1 | 197 | daddr = fl4->daddr; |
1da177e4 | 198 | |
c720c7e8 | 199 | if (!inet->inet_saddr) |
da905bd1 | 200 | inet->inet_saddr = fl4->saddr; |
c720c7e8 | 201 | inet->inet_rcv_saddr = inet->inet_saddr; |
1da177e4 | 202 | |
c720c7e8 | 203 | if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) { |
1da177e4 LT |
204 | /* Reset inherited state */ |
205 | tp->rx_opt.ts_recent = 0; | |
206 | tp->rx_opt.ts_recent_stamp = 0; | |
ee995283 PE |
207 | if (likely(!tp->repair)) |
208 | tp->write_seq = 0; | |
1da177e4 LT |
209 | } |
210 | ||
295ff7ed | 211 | if (tcp_death_row.sysctl_tw_recycle && |
81166dd6 DM |
212 | !tp->rx_opt.ts_recent_stamp && fl4->daddr == daddr) |
213 | tcp_fetch_timewait_stamp(sk, &rt->dst); | |
1da177e4 | 214 | |
c720c7e8 ED |
215 | inet->inet_dport = usin->sin_port; |
216 | inet->inet_daddr = daddr; | |
1da177e4 | 217 | |
d83d8461 | 218 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
219 | if (inet_opt) |
220 | inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
1da177e4 | 221 | |
bee7ca9e | 222 | tp->rx_opt.mss_clamp = TCP_MSS_DEFAULT; |
1da177e4 LT |
223 | |
224 | /* Socket identity is still unknown (sport may be zero). | |
225 | * However we set state to SYN-SENT and not releasing socket | |
226 | * lock select source port, enter ourselves into the hash tables and | |
227 | * complete initialization after this. | |
228 | */ | |
229 | tcp_set_state(sk, TCP_SYN_SENT); | |
a7f5e7f1 | 230 | err = inet_hash_connect(&tcp_death_row, sk); |
1da177e4 LT |
231 | if (err) |
232 | goto failure; | |
233 | ||
da905bd1 | 234 | rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, |
b23dd4fe DM |
235 | inet->inet_sport, inet->inet_dport, sk); |
236 | if (IS_ERR(rt)) { | |
237 | err = PTR_ERR(rt); | |
238 | rt = NULL; | |
1da177e4 | 239 | goto failure; |
b23dd4fe | 240 | } |
1da177e4 | 241 | /* OK, now commit destination to socket. */ |
bcd76111 | 242 | sk->sk_gso_type = SKB_GSO_TCPV4; |
d8d1f30b | 243 | sk_setup_caps(sk, &rt->dst); |
1da177e4 | 244 | |
ee995283 | 245 | if (!tp->write_seq && likely(!tp->repair)) |
c720c7e8 ED |
246 | tp->write_seq = secure_tcp_sequence_number(inet->inet_saddr, |
247 | inet->inet_daddr, | |
248 | inet->inet_sport, | |
1da177e4 LT |
249 | usin->sin_port); |
250 | ||
c720c7e8 | 251 | inet->inet_id = tp->write_seq ^ jiffies; |
1da177e4 | 252 | |
ee995283 PE |
253 | if (likely(!tp->repair)) |
254 | err = tcp_connect(sk); | |
255 | else | |
256 | err = tcp_repair_connect(sk); | |
257 | ||
1da177e4 LT |
258 | rt = NULL; |
259 | if (err) | |
260 | goto failure; | |
261 | ||
262 | return 0; | |
263 | ||
264 | failure: | |
7174259e ACM |
265 | /* |
266 | * This unhashes the socket and releases the local port, | |
267 | * if necessary. | |
268 | */ | |
1da177e4 LT |
269 | tcp_set_state(sk, TCP_CLOSE); |
270 | ip_rt_put(rt); | |
271 | sk->sk_route_caps = 0; | |
c720c7e8 | 272 | inet->inet_dport = 0; |
1da177e4 LT |
273 | return err; |
274 | } | |
4bc2f18b | 275 | EXPORT_SYMBOL(tcp_v4_connect); |
1da177e4 | 276 | |
1da177e4 | 277 | /* |
563d34d0 ED |
278 | * This routine reacts to ICMP_FRAG_NEEDED mtu indications as defined in RFC1191. |
279 | * It can be called through tcp_release_cb() if socket was owned by user | |
280 | * at the time tcp_v4_err() was called to handle ICMP message. | |
1da177e4 | 281 | */ |
563d34d0 | 282 | static void tcp_v4_mtu_reduced(struct sock *sk) |
1da177e4 LT |
283 | { |
284 | struct dst_entry *dst; | |
285 | struct inet_sock *inet = inet_sk(sk); | |
563d34d0 | 286 | u32 mtu = tcp_sk(sk)->mtu_info; |
1da177e4 LT |
287 | |
288 | /* We are not interested in TCP_LISTEN and open_requests (SYN-ACKs | |
289 | * send out by Linux are always <576bytes so they should go through | |
290 | * unfragmented). | |
291 | */ | |
292 | if (sk->sk_state == TCP_LISTEN) | |
293 | return; | |
294 | ||
80d0a69f DM |
295 | dst = inet_csk_update_pmtu(sk, mtu); |
296 | if (!dst) | |
1da177e4 LT |
297 | return; |
298 | ||
1da177e4 LT |
299 | /* Something is about to be wrong... Remember soft error |
300 | * for the case, if this connection will not able to recover. | |
301 | */ | |
302 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) | |
303 | sk->sk_err_soft = EMSGSIZE; | |
304 | ||
305 | mtu = dst_mtu(dst); | |
306 | ||
307 | if (inet->pmtudisc != IP_PMTUDISC_DONT && | |
d83d8461 | 308 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
1da177e4 LT |
309 | tcp_sync_mss(sk, mtu); |
310 | ||
311 | /* Resend the TCP packet because it's | |
312 | * clear that the old packet has been | |
313 | * dropped. This is the new "fast" path mtu | |
314 | * discovery. | |
315 | */ | |
316 | tcp_simple_retransmit(sk); | |
317 | } /* else let the usual retransmit timer handle it */ | |
318 | } | |
319 | ||
55be7a9c DM |
320 | static void do_redirect(struct sk_buff *skb, struct sock *sk) |
321 | { | |
322 | struct dst_entry *dst = __sk_dst_check(sk, 0); | |
323 | ||
1ed5c48f | 324 | if (dst) |
6700c270 | 325 | dst->ops->redirect(dst, sk, skb); |
55be7a9c DM |
326 | } |
327 | ||
1da177e4 LT |
328 | /* |
329 | * This routine is called by the ICMP module when it gets some | |
330 | * sort of error condition. If err < 0 then the socket should | |
331 | * be closed and the error returned to the user. If err > 0 | |
332 | * it's just the icmp type << 8 | icmp code. After adjustment | |
333 | * header points to the first 8 bytes of the tcp header. We need | |
334 | * to find the appropriate port. | |
335 | * | |
336 | * The locking strategy used here is very "optimistic". When | |
337 | * someone else accesses the socket the ICMP is just dropped | |
338 | * and for some paths there is no check at all. | |
339 | * A more general error queue to queue errors for later handling | |
340 | * is probably better. | |
341 | * | |
342 | */ | |
343 | ||
4d1a2d9e | 344 | void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) |
1da177e4 | 345 | { |
b71d1d42 | 346 | const struct iphdr *iph = (const struct iphdr *)icmp_skb->data; |
4d1a2d9e | 347 | struct tcphdr *th = (struct tcphdr *)(icmp_skb->data + (iph->ihl << 2)); |
f1ecd5d9 | 348 | struct inet_connection_sock *icsk; |
1da177e4 LT |
349 | struct tcp_sock *tp; |
350 | struct inet_sock *inet; | |
4d1a2d9e DL |
351 | const int type = icmp_hdr(icmp_skb)->type; |
352 | const int code = icmp_hdr(icmp_skb)->code; | |
1da177e4 | 353 | struct sock *sk; |
f1ecd5d9 | 354 | struct sk_buff *skb; |
168a8f58 | 355 | struct request_sock *req; |
1da177e4 | 356 | __u32 seq; |
f1ecd5d9 | 357 | __u32 remaining; |
1da177e4 | 358 | int err; |
4d1a2d9e | 359 | struct net *net = dev_net(icmp_skb->dev); |
1da177e4 | 360 | |
4d1a2d9e | 361 | if (icmp_skb->len < (iph->ihl << 2) + 8) { |
dcfc23ca | 362 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
363 | return; |
364 | } | |
365 | ||
fd54d716 | 366 | sk = inet_lookup(net, &tcp_hashinfo, iph->daddr, th->dest, |
4d1a2d9e | 367 | iph->saddr, th->source, inet_iif(icmp_skb)); |
1da177e4 | 368 | if (!sk) { |
dcfc23ca | 369 | ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); |
1da177e4 LT |
370 | return; |
371 | } | |
372 | if (sk->sk_state == TCP_TIME_WAIT) { | |
9469c7b4 | 373 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
374 | return; |
375 | } | |
376 | ||
377 | bh_lock_sock(sk); | |
378 | /* If too many ICMPs get dropped on busy | |
379 | * servers this needs to be solved differently. | |
563d34d0 ED |
380 | * We do take care of PMTU discovery (RFC1191) special case : |
381 | * we can receive locally generated ICMP messages while socket is held. | |
1da177e4 | 382 | */ |
563d34d0 ED |
383 | if (sock_owned_by_user(sk) && |
384 | type != ICMP_DEST_UNREACH && | |
385 | code != ICMP_FRAG_NEEDED) | |
de0744af | 386 | NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS); |
1da177e4 LT |
387 | |
388 | if (sk->sk_state == TCP_CLOSE) | |
389 | goto out; | |
390 | ||
97e3ecd1 | 391 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
392 | NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); | |
393 | goto out; | |
394 | } | |
395 | ||
f1ecd5d9 | 396 | icsk = inet_csk(sk); |
1da177e4 | 397 | tp = tcp_sk(sk); |
168a8f58 | 398 | req = tp->fastopen_rsk; |
1da177e4 LT |
399 | seq = ntohl(th->seq); |
400 | if (sk->sk_state != TCP_LISTEN && | |
168a8f58 JC |
401 | !between(seq, tp->snd_una, tp->snd_nxt) && |
402 | (req == NULL || seq != tcp_rsk(req)->snt_isn)) { | |
403 | /* For a Fast Open socket, allow seq to be snt_isn. */ | |
de0744af | 404 | NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
1da177e4 LT |
405 | goto out; |
406 | } | |
407 | ||
408 | switch (type) { | |
55be7a9c DM |
409 | case ICMP_REDIRECT: |
410 | do_redirect(icmp_skb, sk); | |
411 | goto out; | |
1da177e4 LT |
412 | case ICMP_SOURCE_QUENCH: |
413 | /* Just silently ignore these. */ | |
414 | goto out; | |
415 | case ICMP_PARAMETERPROB: | |
416 | err = EPROTO; | |
417 | break; | |
418 | case ICMP_DEST_UNREACH: | |
419 | if (code > NR_ICMP_UNREACH) | |
420 | goto out; | |
421 | ||
422 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ | |
563d34d0 | 423 | tp->mtu_info = info; |
144d56e9 | 424 | if (!sock_owned_by_user(sk)) { |
563d34d0 | 425 | tcp_v4_mtu_reduced(sk); |
144d56e9 ED |
426 | } else { |
427 | if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &tp->tsq_flags)) | |
428 | sock_hold(sk); | |
429 | } | |
1da177e4 LT |
430 | goto out; |
431 | } | |
432 | ||
433 | err = icmp_err_convert[code].errno; | |
f1ecd5d9 DL |
434 | /* check if icmp_skb allows revert of backoff |
435 | * (see draft-zimmermann-tcp-lcd) */ | |
436 | if (code != ICMP_NET_UNREACH && code != ICMP_HOST_UNREACH) | |
437 | break; | |
438 | if (seq != tp->snd_una || !icsk->icsk_retransmits || | |
439 | !icsk->icsk_backoff) | |
440 | break; | |
441 | ||
168a8f58 JC |
442 | /* XXX (TFO) - revisit the following logic for TFO */ |
443 | ||
8f49c270 DM |
444 | if (sock_owned_by_user(sk)) |
445 | break; | |
446 | ||
f1ecd5d9 | 447 | icsk->icsk_backoff--; |
9ad7c049 JC |
448 | inet_csk(sk)->icsk_rto = (tp->srtt ? __tcp_set_rto(tp) : |
449 | TCP_TIMEOUT_INIT) << icsk->icsk_backoff; | |
f1ecd5d9 DL |
450 | tcp_bound_rto(sk); |
451 | ||
452 | skb = tcp_write_queue_head(sk); | |
453 | BUG_ON(!skb); | |
454 | ||
455 | remaining = icsk->icsk_rto - min(icsk->icsk_rto, | |
456 | tcp_time_stamp - TCP_SKB_CB(skb)->when); | |
457 | ||
458 | if (remaining) { | |
459 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, | |
460 | remaining, TCP_RTO_MAX); | |
f1ecd5d9 DL |
461 | } else { |
462 | /* RTO revert clocked out retransmission. | |
463 | * Will retransmit now */ | |
464 | tcp_retransmit_timer(sk); | |
465 | } | |
466 | ||
1da177e4 LT |
467 | break; |
468 | case ICMP_TIME_EXCEEDED: | |
469 | err = EHOSTUNREACH; | |
470 | break; | |
471 | default: | |
472 | goto out; | |
473 | } | |
474 | ||
168a8f58 JC |
475 | /* XXX (TFO) - if it's a TFO socket and has been accepted, rather |
476 | * than following the TCP_SYN_RECV case and closing the socket, | |
477 | * we ignore the ICMP error and keep trying like a fully established | |
478 | * socket. Is this the right thing to do? | |
479 | */ | |
480 | if (req && req->sk == NULL) | |
481 | goto out; | |
482 | ||
1da177e4 | 483 | switch (sk->sk_state) { |
60236fdd | 484 | struct request_sock *req, **prev; |
1da177e4 LT |
485 | case TCP_LISTEN: |
486 | if (sock_owned_by_user(sk)) | |
487 | goto out; | |
488 | ||
463c84b9 ACM |
489 | req = inet_csk_search_req(sk, &prev, th->dest, |
490 | iph->daddr, iph->saddr); | |
1da177e4 LT |
491 | if (!req) |
492 | goto out; | |
493 | ||
494 | /* ICMPs are not backlogged, hence we cannot get | |
495 | an established socket here. | |
496 | */ | |
547b792c | 497 | WARN_ON(req->sk); |
1da177e4 | 498 | |
2e6599cb | 499 | if (seq != tcp_rsk(req)->snt_isn) { |
de0744af | 500 | NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS); |
1da177e4 LT |
501 | goto out; |
502 | } | |
503 | ||
504 | /* | |
505 | * Still in SYN_RECV, just remove it silently. | |
506 | * There is no good way to pass the error to the newly | |
507 | * created socket, and POSIX does not want network | |
508 | * errors returned from accept(). | |
509 | */ | |
463c84b9 | 510 | inet_csk_reqsk_queue_drop(sk, req, prev); |
1da177e4 LT |
511 | goto out; |
512 | ||
513 | case TCP_SYN_SENT: | |
514 | case TCP_SYN_RECV: /* Cannot happen. | |
168a8f58 JC |
515 | It can f.e. if SYNs crossed, |
516 | or Fast Open. | |
1da177e4 LT |
517 | */ |
518 | if (!sock_owned_by_user(sk)) { | |
1da177e4 LT |
519 | sk->sk_err = err; |
520 | ||
521 | sk->sk_error_report(sk); | |
522 | ||
523 | tcp_done(sk); | |
524 | } else { | |
525 | sk->sk_err_soft = err; | |
526 | } | |
527 | goto out; | |
528 | } | |
529 | ||
530 | /* If we've already connected we will keep trying | |
531 | * until we time out, or the user gives up. | |
532 | * | |
533 | * rfc1122 4.2.3.9 allows to consider as hard errors | |
534 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, | |
535 | * but it is obsoleted by pmtu discovery). | |
536 | * | |
537 | * Note, that in modern internet, where routing is unreliable | |
538 | * and in each dark corner broken firewalls sit, sending random | |
539 | * errors ordered by their masters even this two messages finally lose | |
540 | * their original sense (even Linux sends invalid PORT_UNREACHs) | |
541 | * | |
542 | * Now we are in compliance with RFCs. | |
543 | * --ANK (980905) | |
544 | */ | |
545 | ||
546 | inet = inet_sk(sk); | |
547 | if (!sock_owned_by_user(sk) && inet->recverr) { | |
548 | sk->sk_err = err; | |
549 | sk->sk_error_report(sk); | |
550 | } else { /* Only an error on timeout */ | |
551 | sk->sk_err_soft = err; | |
552 | } | |
553 | ||
554 | out: | |
555 | bh_unlock_sock(sk); | |
556 | sock_put(sk); | |
557 | } | |
558 | ||
419f9f89 HX |
559 | static void __tcp_v4_send_check(struct sk_buff *skb, |
560 | __be32 saddr, __be32 daddr) | |
1da177e4 | 561 | { |
aa8223c7 | 562 | struct tcphdr *th = tcp_hdr(skb); |
1da177e4 | 563 | |
84fa7933 | 564 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
419f9f89 | 565 | th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0); |
663ead3b | 566 | skb->csum_start = skb_transport_header(skb) - skb->head; |
ff1dcadb | 567 | skb->csum_offset = offsetof(struct tcphdr, check); |
1da177e4 | 568 | } else { |
419f9f89 | 569 | th->check = tcp_v4_check(skb->len, saddr, daddr, |
07f0757a | 570 | csum_partial(th, |
1da177e4 LT |
571 | th->doff << 2, |
572 | skb->csum)); | |
573 | } | |
574 | } | |
575 | ||
419f9f89 | 576 | /* This routine computes an IPv4 TCP checksum. */ |
bb296246 | 577 | void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb) |
419f9f89 | 578 | { |
cf533ea5 | 579 | const struct inet_sock *inet = inet_sk(sk); |
419f9f89 HX |
580 | |
581 | __tcp_v4_send_check(skb, inet->inet_saddr, inet->inet_daddr); | |
582 | } | |
4bc2f18b | 583 | EXPORT_SYMBOL(tcp_v4_send_check); |
419f9f89 | 584 | |
a430a43d HX |
585 | int tcp_v4_gso_send_check(struct sk_buff *skb) |
586 | { | |
eddc9ec5 | 587 | const struct iphdr *iph; |
a430a43d HX |
588 | struct tcphdr *th; |
589 | ||
590 | if (!pskb_may_pull(skb, sizeof(*th))) | |
591 | return -EINVAL; | |
592 | ||
eddc9ec5 | 593 | iph = ip_hdr(skb); |
aa8223c7 | 594 | th = tcp_hdr(skb); |
a430a43d HX |
595 | |
596 | th->check = 0; | |
84fa7933 | 597 | skb->ip_summed = CHECKSUM_PARTIAL; |
419f9f89 | 598 | __tcp_v4_send_check(skb, iph->saddr, iph->daddr); |
a430a43d HX |
599 | return 0; |
600 | } | |
601 | ||
1da177e4 LT |
602 | /* |
603 | * This routine will send an RST to the other tcp. | |
604 | * | |
605 | * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.) | |
606 | * for reset. | |
607 | * Answer: if a packet caused RST, it is not for a socket | |
608 | * existing in our system, if it is matched to a socket, | |
609 | * it is just duplicate segment or bug in other side's TCP. | |
610 | * So that we build reply only basing on parameters | |
611 | * arrived with segment. | |
612 | * Exception: precedence violation. We do not implement it in any case. | |
613 | */ | |
614 | ||
cfb6eeb4 | 615 | static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 616 | { |
cf533ea5 | 617 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
618 | struct { |
619 | struct tcphdr th; | |
620 | #ifdef CONFIG_TCP_MD5SIG | |
714e85be | 621 | __be32 opt[(TCPOLEN_MD5SIG_ALIGNED >> 2)]; |
cfb6eeb4 YH |
622 | #endif |
623 | } rep; | |
1da177e4 | 624 | struct ip_reply_arg arg; |
cfb6eeb4 YH |
625 | #ifdef CONFIG_TCP_MD5SIG |
626 | struct tcp_md5sig_key *key; | |
658ddaaf SL |
627 | const __u8 *hash_location = NULL; |
628 | unsigned char newhash[16]; | |
629 | int genhash; | |
630 | struct sock *sk1 = NULL; | |
cfb6eeb4 | 631 | #endif |
a86b1e30 | 632 | struct net *net; |
1da177e4 LT |
633 | |
634 | /* Never send a reset in response to a reset. */ | |
635 | if (th->rst) | |
636 | return; | |
637 | ||
511c3f92 | 638 | if (skb_rtable(skb)->rt_type != RTN_LOCAL) |
1da177e4 LT |
639 | return; |
640 | ||
641 | /* Swap the send and the receive. */ | |
cfb6eeb4 YH |
642 | memset(&rep, 0, sizeof(rep)); |
643 | rep.th.dest = th->source; | |
644 | rep.th.source = th->dest; | |
645 | rep.th.doff = sizeof(struct tcphdr) / 4; | |
646 | rep.th.rst = 1; | |
1da177e4 LT |
647 | |
648 | if (th->ack) { | |
cfb6eeb4 | 649 | rep.th.seq = th->ack_seq; |
1da177e4 | 650 | } else { |
cfb6eeb4 YH |
651 | rep.th.ack = 1; |
652 | rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin + | |
653 | skb->len - (th->doff << 2)); | |
1da177e4 LT |
654 | } |
655 | ||
7174259e | 656 | memset(&arg, 0, sizeof(arg)); |
cfb6eeb4 YH |
657 | arg.iov[0].iov_base = (unsigned char *)&rep; |
658 | arg.iov[0].iov_len = sizeof(rep.th); | |
659 | ||
660 | #ifdef CONFIG_TCP_MD5SIG | |
658ddaaf SL |
661 | hash_location = tcp_parse_md5sig_option(th); |
662 | if (!sk && hash_location) { | |
663 | /* | |
664 | * active side is lost. Try to find listening socket through | |
665 | * source port, and then find md5 key through listening socket. | |
666 | * we are not loose security here: | |
667 | * Incoming packet is checked with md5 hash with finding key, | |
668 | * no RST generated if md5 hash doesn't match. | |
669 | */ | |
670 | sk1 = __inet_lookup_listener(dev_net(skb_dst(skb)->dev), | |
671 | &tcp_hashinfo, ip_hdr(skb)->daddr, | |
672 | ntohs(th->source), inet_iif(skb)); | |
673 | /* don't send rst if it can't find key */ | |
674 | if (!sk1) | |
675 | return; | |
676 | rcu_read_lock(); | |
677 | key = tcp_md5_do_lookup(sk1, (union tcp_md5_addr *) | |
678 | &ip_hdr(skb)->saddr, AF_INET); | |
679 | if (!key) | |
680 | goto release_sk1; | |
681 | ||
682 | genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, NULL, skb); | |
683 | if (genhash || memcmp(hash_location, newhash, 16) != 0) | |
684 | goto release_sk1; | |
685 | } else { | |
686 | key = sk ? tcp_md5_do_lookup(sk, (union tcp_md5_addr *) | |
687 | &ip_hdr(skb)->saddr, | |
688 | AF_INET) : NULL; | |
689 | } | |
690 | ||
cfb6eeb4 YH |
691 | if (key) { |
692 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | | |
693 | (TCPOPT_NOP << 16) | | |
694 | (TCPOPT_MD5SIG << 8) | | |
695 | TCPOLEN_MD5SIG); | |
696 | /* Update length and the length the header thinks exists */ | |
697 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
698 | rep.th.doff = arg.iov[0].iov_len / 4; | |
699 | ||
49a72dfb | 700 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[1], |
78e645cb IJ |
701 | key, ip_hdr(skb)->saddr, |
702 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
703 | } |
704 | #endif | |
eddc9ec5 ACM |
705 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
706 | ip_hdr(skb)->saddr, /* XXX */ | |
52cd5750 | 707 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
1da177e4 | 708 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; |
88ef4a5a | 709 | arg.flags = (sk && inet_sk(sk)->transparent) ? IP_REPLY_ARG_NOSRCCHECK : 0; |
e2446eaa | 710 | /* When socket is gone, all binding information is lost. |
4c675258 AK |
711 | * routing might fail in this case. No choice here, if we choose to force |
712 | * input interface, we will misroute in case of asymmetric route. | |
e2446eaa | 713 | */ |
4c675258 AK |
714 | if (sk) |
715 | arg.bound_dev_if = sk->sk_bound_dev_if; | |
1da177e4 | 716 | |
adf30907 | 717 | net = dev_net(skb_dst(skb)->dev); |
66b13d99 | 718 | arg.tos = ip_hdr(skb)->tos; |
be9f4a44 | 719 | ip_send_unicast_reply(net, skb, ip_hdr(skb)->saddr, |
70e73416 | 720 | ip_hdr(skb)->daddr, &arg, arg.iov[0].iov_len); |
1da177e4 | 721 | |
63231bdd PE |
722 | TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); |
723 | TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); | |
658ddaaf SL |
724 | |
725 | #ifdef CONFIG_TCP_MD5SIG | |
726 | release_sk1: | |
727 | if (sk1) { | |
728 | rcu_read_unlock(); | |
729 | sock_put(sk1); | |
730 | } | |
731 | #endif | |
1da177e4 LT |
732 | } |
733 | ||
734 | /* The code following below sending ACKs in SYN-RECV and TIME-WAIT states | |
735 | outside socket context is ugly, certainly. What can I do? | |
736 | */ | |
737 | ||
9501f972 YH |
738 | static void tcp_v4_send_ack(struct sk_buff *skb, u32 seq, u32 ack, |
739 | u32 win, u32 ts, int oif, | |
88ef4a5a | 740 | struct tcp_md5sig_key *key, |
66b13d99 | 741 | int reply_flags, u8 tos) |
1da177e4 | 742 | { |
cf533ea5 | 743 | const struct tcphdr *th = tcp_hdr(skb); |
1da177e4 LT |
744 | struct { |
745 | struct tcphdr th; | |
714e85be | 746 | __be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2) |
cfb6eeb4 | 747 | #ifdef CONFIG_TCP_MD5SIG |
714e85be | 748 | + (TCPOLEN_MD5SIG_ALIGNED >> 2) |
cfb6eeb4 YH |
749 | #endif |
750 | ]; | |
1da177e4 LT |
751 | } rep; |
752 | struct ip_reply_arg arg; | |
adf30907 | 753 | struct net *net = dev_net(skb_dst(skb)->dev); |
1da177e4 LT |
754 | |
755 | memset(&rep.th, 0, sizeof(struct tcphdr)); | |
7174259e | 756 | memset(&arg, 0, sizeof(arg)); |
1da177e4 LT |
757 | |
758 | arg.iov[0].iov_base = (unsigned char *)&rep; | |
759 | arg.iov[0].iov_len = sizeof(rep.th); | |
760 | if (ts) { | |
cfb6eeb4 YH |
761 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | |
762 | (TCPOPT_TIMESTAMP << 8) | | |
763 | TCPOLEN_TIMESTAMP); | |
764 | rep.opt[1] = htonl(tcp_time_stamp); | |
765 | rep.opt[2] = htonl(ts); | |
cb48cfe8 | 766 | arg.iov[0].iov_len += TCPOLEN_TSTAMP_ALIGNED; |
1da177e4 LT |
767 | } |
768 | ||
769 | /* Swap the send and the receive. */ | |
770 | rep.th.dest = th->source; | |
771 | rep.th.source = th->dest; | |
772 | rep.th.doff = arg.iov[0].iov_len / 4; | |
773 | rep.th.seq = htonl(seq); | |
774 | rep.th.ack_seq = htonl(ack); | |
775 | rep.th.ack = 1; | |
776 | rep.th.window = htons(win); | |
777 | ||
cfb6eeb4 | 778 | #ifdef CONFIG_TCP_MD5SIG |
cfb6eeb4 YH |
779 | if (key) { |
780 | int offset = (ts) ? 3 : 0; | |
781 | ||
782 | rep.opt[offset++] = htonl((TCPOPT_NOP << 24) | | |
783 | (TCPOPT_NOP << 16) | | |
784 | (TCPOPT_MD5SIG << 8) | | |
785 | TCPOLEN_MD5SIG); | |
786 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
787 | rep.th.doff = arg.iov[0].iov_len/4; | |
788 | ||
49a72dfb | 789 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[offset], |
90b7e112 AL |
790 | key, ip_hdr(skb)->saddr, |
791 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
792 | } |
793 | #endif | |
88ef4a5a | 794 | arg.flags = reply_flags; |
eddc9ec5 ACM |
795 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
796 | ip_hdr(skb)->saddr, /* XXX */ | |
1da177e4 LT |
797 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
798 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; | |
9501f972 YH |
799 | if (oif) |
800 | arg.bound_dev_if = oif; | |
66b13d99 | 801 | arg.tos = tos; |
be9f4a44 | 802 | ip_send_unicast_reply(net, skb, ip_hdr(skb)->saddr, |
70e73416 | 803 | ip_hdr(skb)->daddr, &arg, arg.iov[0].iov_len); |
1da177e4 | 804 | |
63231bdd | 805 | TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); |
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 | |
9501f972 | 813 | tcp_v4_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, |
7174259e | 814 | tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, |
9501f972 YH |
815 | tcptw->tw_ts_recent, |
816 | tw->tw_bound_dev_if, | |
88ef4a5a | 817 | tcp_twsk_md5_key(tcptw), |
66b13d99 ED |
818 | tw->tw_transparent ? IP_REPLY_ARG_NOSRCCHECK : 0, |
819 | tw->tw_tos | |
9501f972 | 820 | ); |
1da177e4 | 821 | |
8feaf0c0 | 822 | inet_twsk_put(tw); |
1da177e4 LT |
823 | } |
824 | ||
6edafaaf | 825 | static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, |
7174259e | 826 | struct request_sock *req) |
1da177e4 | 827 | { |
168a8f58 JC |
828 | /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV |
829 | * sk->sk_state == TCP_SYN_RECV -> for Fast Open. | |
830 | */ | |
831 | tcp_v4_send_ack(skb, (sk->sk_state == TCP_LISTEN) ? | |
832 | tcp_rsk(req)->snt_isn + 1 : tcp_sk(sk)->snd_nxt, | |
833 | tcp_rsk(req)->rcv_nxt, req->rcv_wnd, | |
9501f972 YH |
834 | req->ts_recent, |
835 | 0, | |
a915da9b ED |
836 | tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->daddr, |
837 | AF_INET), | |
66b13d99 ED |
838 | inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0, |
839 | ip_hdr(skb)->tos); | |
1da177e4 LT |
840 | } |
841 | ||
1da177e4 | 842 | /* |
9bf1d83e | 843 | * Send a SYN-ACK after having received a SYN. |
60236fdd | 844 | * This still operates on a request_sock only, not on a big |
1da177e4 LT |
845 | * socket. |
846 | */ | |
72659ecc OP |
847 | static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst, |
848 | struct request_sock *req, | |
fff32699 | 849 | struct request_values *rvp, |
7586eceb ED |
850 | u16 queue_mapping, |
851 | bool nocache) | |
1da177e4 | 852 | { |
2e6599cb | 853 | const struct inet_request_sock *ireq = inet_rsk(req); |
6bd023f3 | 854 | struct flowi4 fl4; |
1da177e4 LT |
855 | int err = -1; |
856 | struct sk_buff * skb; | |
857 | ||
858 | /* First, grab a route. */ | |
ba3f7f04 | 859 | if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL) |
fd80eb94 | 860 | return -1; |
1da177e4 | 861 | |
8336886f | 862 | skb = tcp_make_synack(sk, dst, req, rvp, NULL); |
1da177e4 LT |
863 | |
864 | if (skb) { | |
419f9f89 | 865 | __tcp_v4_send_check(skb, ireq->loc_addr, ireq->rmt_addr); |
1da177e4 | 866 | |
fff32699 | 867 | skb_set_queue_mapping(skb, queue_mapping); |
2e6599cb ACM |
868 | err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr, |
869 | ireq->rmt_addr, | |
870 | ireq->opt); | |
b9df3cb8 | 871 | err = net_xmit_eval(err); |
016818d0 NC |
872 | if (!tcp_rsk(req)->snt_synack && !err) |
873 | tcp_rsk(req)->snt_synack = tcp_time_stamp; | |
1da177e4 LT |
874 | } |
875 | ||
1da177e4 LT |
876 | return err; |
877 | } | |
878 | ||
72659ecc | 879 | static int tcp_v4_rtx_synack(struct sock *sk, struct request_sock *req, |
e6b4d113 | 880 | struct request_values *rvp) |
fd80eb94 | 881 | { |
72659ecc | 882 | TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS); |
7586eceb | 883 | return tcp_v4_send_synack(sk, NULL, req, rvp, 0, false); |
fd80eb94 DL |
884 | } |
885 | ||
1da177e4 | 886 | /* |
60236fdd | 887 | * IPv4 request_sock destructor. |
1da177e4 | 888 | */ |
60236fdd | 889 | static void tcp_v4_reqsk_destructor(struct request_sock *req) |
1da177e4 | 890 | { |
a51482bd | 891 | kfree(inet_rsk(req)->opt); |
1da177e4 LT |
892 | } |
893 | ||
946cedcc | 894 | /* |
a2a385d6 | 895 | * Return true if a syncookie should be sent |
946cedcc | 896 | */ |
a2a385d6 | 897 | bool tcp_syn_flood_action(struct sock *sk, |
946cedcc ED |
898 | const struct sk_buff *skb, |
899 | const char *proto) | |
1da177e4 | 900 | { |
946cedcc | 901 | const char *msg = "Dropping request"; |
a2a385d6 | 902 | bool want_cookie = false; |
946cedcc ED |
903 | struct listen_sock *lopt; |
904 | ||
905 | ||
1da177e4 | 906 | |
2a1d4bd4 | 907 | #ifdef CONFIG_SYN_COOKIES |
946cedcc | 908 | if (sysctl_tcp_syncookies) { |
2a1d4bd4 | 909 | msg = "Sending cookies"; |
a2a385d6 | 910 | want_cookie = true; |
946cedcc ED |
911 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDOCOOKIES); |
912 | } else | |
80e40daa | 913 | #endif |
946cedcc ED |
914 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPREQQFULLDROP); |
915 | ||
916 | lopt = inet_csk(sk)->icsk_accept_queue.listen_opt; | |
917 | if (!lopt->synflood_warned) { | |
918 | lopt->synflood_warned = 1; | |
afd46503 | 919 | pr_info("%s: Possible SYN flooding on port %d. %s. Check SNMP counters.\n", |
946cedcc ED |
920 | proto, ntohs(tcp_hdr(skb)->dest), msg); |
921 | } | |
922 | return want_cookie; | |
2a1d4bd4 | 923 | } |
946cedcc | 924 | EXPORT_SYMBOL(tcp_syn_flood_action); |
1da177e4 LT |
925 | |
926 | /* | |
60236fdd | 927 | * Save and compile IPv4 options into the request_sock if needed. |
1da177e4 | 928 | */ |
5dff747b | 929 | static struct ip_options_rcu *tcp_v4_save_options(struct sk_buff *skb) |
1da177e4 | 930 | { |
f6d8bd05 ED |
931 | const struct ip_options *opt = &(IPCB(skb)->opt); |
932 | struct ip_options_rcu *dopt = NULL; | |
1da177e4 LT |
933 | |
934 | if (opt && opt->optlen) { | |
f6d8bd05 ED |
935 | int opt_size = sizeof(*dopt) + opt->optlen; |
936 | ||
1da177e4 LT |
937 | dopt = kmalloc(opt_size, GFP_ATOMIC); |
938 | if (dopt) { | |
f6d8bd05 | 939 | if (ip_options_echo(&dopt->opt, skb)) { |
1da177e4 LT |
940 | kfree(dopt); |
941 | dopt = NULL; | |
942 | } | |
943 | } | |
944 | } | |
945 | return dopt; | |
946 | } | |
947 | ||
cfb6eeb4 YH |
948 | #ifdef CONFIG_TCP_MD5SIG |
949 | /* | |
950 | * RFC2385 MD5 checksumming requires a mapping of | |
951 | * IP address->MD5 Key. | |
952 | * We need to maintain these in the sk structure. | |
953 | */ | |
954 | ||
955 | /* Find the Key structure for an address. */ | |
a915da9b ED |
956 | struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk, |
957 | const union tcp_md5_addr *addr, | |
958 | int family) | |
cfb6eeb4 YH |
959 | { |
960 | struct tcp_sock *tp = tcp_sk(sk); | |
a915da9b ED |
961 | struct tcp_md5sig_key *key; |
962 | struct hlist_node *pos; | |
963 | unsigned int size = sizeof(struct in_addr); | |
a8afca03 | 964 | struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 965 | |
a8afca03 ED |
966 | /* caller either holds rcu_read_lock() or socket lock */ |
967 | md5sig = rcu_dereference_check(tp->md5sig_info, | |
b4fb05ea ED |
968 | sock_owned_by_user(sk) || |
969 | lockdep_is_held(&sk->sk_lock.slock)); | |
a8afca03 | 970 | if (!md5sig) |
cfb6eeb4 | 971 | return NULL; |
a915da9b ED |
972 | #if IS_ENABLED(CONFIG_IPV6) |
973 | if (family == AF_INET6) | |
974 | size = sizeof(struct in6_addr); | |
975 | #endif | |
a8afca03 | 976 | hlist_for_each_entry_rcu(key, pos, &md5sig->head, node) { |
a915da9b ED |
977 | if (key->family != family) |
978 | continue; | |
979 | if (!memcmp(&key->addr, addr, size)) | |
980 | return key; | |
cfb6eeb4 YH |
981 | } |
982 | return NULL; | |
983 | } | |
a915da9b | 984 | EXPORT_SYMBOL(tcp_md5_do_lookup); |
cfb6eeb4 YH |
985 | |
986 | struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk, | |
987 | struct sock *addr_sk) | |
988 | { | |
a915da9b ED |
989 | union tcp_md5_addr *addr; |
990 | ||
991 | addr = (union tcp_md5_addr *)&inet_sk(addr_sk)->inet_daddr; | |
992 | return tcp_md5_do_lookup(sk, addr, AF_INET); | |
cfb6eeb4 | 993 | } |
cfb6eeb4 YH |
994 | EXPORT_SYMBOL(tcp_v4_md5_lookup); |
995 | ||
f5b99bcd AB |
996 | static struct tcp_md5sig_key *tcp_v4_reqsk_md5_lookup(struct sock *sk, |
997 | struct request_sock *req) | |
cfb6eeb4 | 998 | { |
a915da9b ED |
999 | union tcp_md5_addr *addr; |
1000 | ||
1001 | addr = (union tcp_md5_addr *)&inet_rsk(req)->rmt_addr; | |
1002 | return tcp_md5_do_lookup(sk, addr, AF_INET); | |
cfb6eeb4 YH |
1003 | } |
1004 | ||
1005 | /* This can be called on a newly created socket, from other files */ | |
a915da9b ED |
1006 | int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, |
1007 | int family, const u8 *newkey, u8 newkeylen, gfp_t gfp) | |
cfb6eeb4 YH |
1008 | { |
1009 | /* Add Key to the list */ | |
b0a713e9 | 1010 | struct tcp_md5sig_key *key; |
cfb6eeb4 | 1011 | struct tcp_sock *tp = tcp_sk(sk); |
a915da9b | 1012 | struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 1013 | |
a915da9b | 1014 | key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&addr, AF_INET); |
cfb6eeb4 YH |
1015 | if (key) { |
1016 | /* Pre-existing entry - just update that one. */ | |
a915da9b | 1017 | memcpy(key->key, newkey, newkeylen); |
b0a713e9 | 1018 | key->keylen = newkeylen; |
a915da9b ED |
1019 | return 0; |
1020 | } | |
260fcbeb | 1021 | |
a8afca03 ED |
1022 | md5sig = rcu_dereference_protected(tp->md5sig_info, |
1023 | sock_owned_by_user(sk)); | |
a915da9b ED |
1024 | if (!md5sig) { |
1025 | md5sig = kmalloc(sizeof(*md5sig), gfp); | |
1026 | if (!md5sig) | |
cfb6eeb4 | 1027 | return -ENOMEM; |
cfb6eeb4 | 1028 | |
a915da9b ED |
1029 | sk_nocaps_add(sk, NETIF_F_GSO_MASK); |
1030 | INIT_HLIST_HEAD(&md5sig->head); | |
a8afca03 | 1031 | rcu_assign_pointer(tp->md5sig_info, md5sig); |
a915da9b | 1032 | } |
cfb6eeb4 | 1033 | |
5f3d9cb2 | 1034 | key = sock_kmalloc(sk, sizeof(*key), gfp); |
a915da9b ED |
1035 | if (!key) |
1036 | return -ENOMEM; | |
1037 | if (hlist_empty(&md5sig->head) && !tcp_alloc_md5sig_pool(sk)) { | |
5f3d9cb2 | 1038 | sock_kfree_s(sk, key, sizeof(*key)); |
a915da9b | 1039 | return -ENOMEM; |
cfb6eeb4 | 1040 | } |
a915da9b ED |
1041 | |
1042 | memcpy(key->key, newkey, newkeylen); | |
1043 | key->keylen = newkeylen; | |
1044 | key->family = family; | |
1045 | memcpy(&key->addr, addr, | |
1046 | (family == AF_INET6) ? sizeof(struct in6_addr) : | |
1047 | sizeof(struct in_addr)); | |
1048 | hlist_add_head_rcu(&key->node, &md5sig->head); | |
cfb6eeb4 YH |
1049 | return 0; |
1050 | } | |
a915da9b | 1051 | EXPORT_SYMBOL(tcp_md5_do_add); |
cfb6eeb4 | 1052 | |
a915da9b | 1053 | int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family) |
cfb6eeb4 YH |
1054 | { |
1055 | struct tcp_sock *tp = tcp_sk(sk); | |
a915da9b | 1056 | struct tcp_md5sig_key *key; |
a8afca03 | 1057 | struct tcp_md5sig_info *md5sig; |
a915da9b ED |
1058 | |
1059 | key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&addr, AF_INET); | |
1060 | if (!key) | |
1061 | return -ENOENT; | |
1062 | hlist_del_rcu(&key->node); | |
5f3d9cb2 | 1063 | atomic_sub(sizeof(*key), &sk->sk_omem_alloc); |
a915da9b | 1064 | kfree_rcu(key, rcu); |
a8afca03 ED |
1065 | md5sig = rcu_dereference_protected(tp->md5sig_info, |
1066 | sock_owned_by_user(sk)); | |
1067 | if (hlist_empty(&md5sig->head)) | |
a915da9b ED |
1068 | tcp_free_md5sig_pool(); |
1069 | return 0; | |
cfb6eeb4 | 1070 | } |
a915da9b | 1071 | EXPORT_SYMBOL(tcp_md5_do_del); |
cfb6eeb4 | 1072 | |
a915da9b | 1073 | void tcp_clear_md5_list(struct sock *sk) |
cfb6eeb4 YH |
1074 | { |
1075 | struct tcp_sock *tp = tcp_sk(sk); | |
a915da9b ED |
1076 | struct tcp_md5sig_key *key; |
1077 | struct hlist_node *pos, *n; | |
a8afca03 | 1078 | struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 1079 | |
a8afca03 ED |
1080 | md5sig = rcu_dereference_protected(tp->md5sig_info, 1); |
1081 | ||
1082 | if (!hlist_empty(&md5sig->head)) | |
cfb6eeb4 | 1083 | tcp_free_md5sig_pool(); |
a8afca03 | 1084 | hlist_for_each_entry_safe(key, pos, n, &md5sig->head, node) { |
a915da9b | 1085 | hlist_del_rcu(&key->node); |
5f3d9cb2 | 1086 | atomic_sub(sizeof(*key), &sk->sk_omem_alloc); |
a915da9b | 1087 | kfree_rcu(key, rcu); |
cfb6eeb4 YH |
1088 | } |
1089 | } | |
1090 | ||
7174259e ACM |
1091 | static int tcp_v4_parse_md5_keys(struct sock *sk, char __user *optval, |
1092 | int optlen) | |
cfb6eeb4 YH |
1093 | { |
1094 | struct tcp_md5sig cmd; | |
1095 | struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr; | |
cfb6eeb4 YH |
1096 | |
1097 | if (optlen < sizeof(cmd)) | |
1098 | return -EINVAL; | |
1099 | ||
7174259e | 1100 | if (copy_from_user(&cmd, optval, sizeof(cmd))) |
cfb6eeb4 YH |
1101 | return -EFAULT; |
1102 | ||
1103 | if (sin->sin_family != AF_INET) | |
1104 | return -EINVAL; | |
1105 | ||
a8afca03 | 1106 | if (!cmd.tcpm_key || !cmd.tcpm_keylen) |
a915da9b ED |
1107 | return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr, |
1108 | AF_INET); | |
cfb6eeb4 YH |
1109 | |
1110 | if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) | |
1111 | return -EINVAL; | |
1112 | ||
a915da9b ED |
1113 | return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr, |
1114 | AF_INET, cmd.tcpm_key, cmd.tcpm_keylen, | |
1115 | GFP_KERNEL); | |
cfb6eeb4 YH |
1116 | } |
1117 | ||
49a72dfb AL |
1118 | static int tcp_v4_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp, |
1119 | __be32 daddr, __be32 saddr, int nbytes) | |
cfb6eeb4 | 1120 | { |
cfb6eeb4 | 1121 | struct tcp4_pseudohdr *bp; |
49a72dfb | 1122 | struct scatterlist sg; |
cfb6eeb4 YH |
1123 | |
1124 | bp = &hp->md5_blk.ip4; | |
cfb6eeb4 YH |
1125 | |
1126 | /* | |
49a72dfb | 1127 | * 1. the TCP pseudo-header (in the order: source IP address, |
cfb6eeb4 YH |
1128 | * destination IP address, zero-padded protocol number, and |
1129 | * segment length) | |
1130 | */ | |
1131 | bp->saddr = saddr; | |
1132 | bp->daddr = daddr; | |
1133 | bp->pad = 0; | |
076fb722 | 1134 | bp->protocol = IPPROTO_TCP; |
49a72dfb | 1135 | bp->len = cpu_to_be16(nbytes); |
c7da57a1 | 1136 | |
49a72dfb AL |
1137 | sg_init_one(&sg, bp, sizeof(*bp)); |
1138 | return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp)); | |
1139 | } | |
1140 | ||
a915da9b | 1141 | static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, |
318cf7aa | 1142 | __be32 daddr, __be32 saddr, const struct tcphdr *th) |
49a72dfb AL |
1143 | { |
1144 | struct tcp_md5sig_pool *hp; | |
1145 | struct hash_desc *desc; | |
1146 | ||
1147 | hp = tcp_get_md5sig_pool(); | |
1148 | if (!hp) | |
1149 | goto clear_hash_noput; | |
1150 | desc = &hp->md5_desc; | |
1151 | ||
1152 | if (crypto_hash_init(desc)) | |
1153 | goto clear_hash; | |
1154 | if (tcp_v4_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2)) | |
1155 | goto clear_hash; | |
1156 | if (tcp_md5_hash_header(hp, th)) | |
1157 | goto clear_hash; | |
1158 | if (tcp_md5_hash_key(hp, key)) | |
1159 | goto clear_hash; | |
1160 | if (crypto_hash_final(desc, md5_hash)) | |
cfb6eeb4 YH |
1161 | goto clear_hash; |
1162 | ||
cfb6eeb4 | 1163 | tcp_put_md5sig_pool(); |
cfb6eeb4 | 1164 | return 0; |
49a72dfb | 1165 | |
cfb6eeb4 YH |
1166 | clear_hash: |
1167 | tcp_put_md5sig_pool(); | |
1168 | clear_hash_noput: | |
1169 | memset(md5_hash, 0, 16); | |
49a72dfb | 1170 | return 1; |
cfb6eeb4 YH |
1171 | } |
1172 | ||
49a72dfb | 1173 | int tcp_v4_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key, |
318cf7aa ED |
1174 | const struct sock *sk, const struct request_sock *req, |
1175 | const struct sk_buff *skb) | |
cfb6eeb4 | 1176 | { |
49a72dfb AL |
1177 | struct tcp_md5sig_pool *hp; |
1178 | struct hash_desc *desc; | |
318cf7aa | 1179 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
1180 | __be32 saddr, daddr; |
1181 | ||
1182 | if (sk) { | |
c720c7e8 ED |
1183 | saddr = inet_sk(sk)->inet_saddr; |
1184 | daddr = inet_sk(sk)->inet_daddr; | |
49a72dfb AL |
1185 | } else if (req) { |
1186 | saddr = inet_rsk(req)->loc_addr; | |
1187 | daddr = inet_rsk(req)->rmt_addr; | |
cfb6eeb4 | 1188 | } else { |
49a72dfb AL |
1189 | const struct iphdr *iph = ip_hdr(skb); |
1190 | saddr = iph->saddr; | |
1191 | daddr = iph->daddr; | |
cfb6eeb4 | 1192 | } |
49a72dfb AL |
1193 | |
1194 | hp = tcp_get_md5sig_pool(); | |
1195 | if (!hp) | |
1196 | goto clear_hash_noput; | |
1197 | desc = &hp->md5_desc; | |
1198 | ||
1199 | if (crypto_hash_init(desc)) | |
1200 | goto clear_hash; | |
1201 | ||
1202 | if (tcp_v4_md5_hash_pseudoheader(hp, daddr, saddr, skb->len)) | |
1203 | goto clear_hash; | |
1204 | if (tcp_md5_hash_header(hp, th)) | |
1205 | goto clear_hash; | |
1206 | if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) | |
1207 | goto clear_hash; | |
1208 | if (tcp_md5_hash_key(hp, key)) | |
1209 | goto clear_hash; | |
1210 | if (crypto_hash_final(desc, md5_hash)) | |
1211 | goto clear_hash; | |
1212 | ||
1213 | tcp_put_md5sig_pool(); | |
1214 | return 0; | |
1215 | ||
1216 | clear_hash: | |
1217 | tcp_put_md5sig_pool(); | |
1218 | clear_hash_noput: | |
1219 | memset(md5_hash, 0, 16); | |
1220 | return 1; | |
cfb6eeb4 | 1221 | } |
49a72dfb | 1222 | EXPORT_SYMBOL(tcp_v4_md5_hash_skb); |
cfb6eeb4 | 1223 | |
a2a385d6 | 1224 | static bool tcp_v4_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb) |
cfb6eeb4 YH |
1225 | { |
1226 | /* | |
1227 | * This gets called for each TCP segment that arrives | |
1228 | * so we want to be efficient. | |
1229 | * We have 3 drop cases: | |
1230 | * o No MD5 hash and one expected. | |
1231 | * o MD5 hash and we're not expecting one. | |
1232 | * o MD5 hash and its wrong. | |
1233 | */ | |
cf533ea5 | 1234 | const __u8 *hash_location = NULL; |
cfb6eeb4 | 1235 | struct tcp_md5sig_key *hash_expected; |
eddc9ec5 | 1236 | const struct iphdr *iph = ip_hdr(skb); |
cf533ea5 | 1237 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 | 1238 | int genhash; |
cfb6eeb4 YH |
1239 | unsigned char newhash[16]; |
1240 | ||
a915da9b ED |
1241 | hash_expected = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&iph->saddr, |
1242 | AF_INET); | |
7d5d5525 | 1243 | hash_location = tcp_parse_md5sig_option(th); |
cfb6eeb4 | 1244 | |
cfb6eeb4 YH |
1245 | /* We've parsed the options - do we have a hash? */ |
1246 | if (!hash_expected && !hash_location) | |
a2a385d6 | 1247 | return false; |
cfb6eeb4 YH |
1248 | |
1249 | if (hash_expected && !hash_location) { | |
785957d3 | 1250 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); |
a2a385d6 | 1251 | return true; |
cfb6eeb4 YH |
1252 | } |
1253 | ||
1254 | if (!hash_expected && hash_location) { | |
785957d3 | 1255 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); |
a2a385d6 | 1256 | return true; |
cfb6eeb4 YH |
1257 | } |
1258 | ||
1259 | /* Okay, so this is hash_expected and hash_location - | |
1260 | * so we need to calculate the checksum. | |
1261 | */ | |
49a72dfb AL |
1262 | genhash = tcp_v4_md5_hash_skb(newhash, |
1263 | hash_expected, | |
1264 | NULL, NULL, skb); | |
cfb6eeb4 YH |
1265 | |
1266 | if (genhash || memcmp(hash_location, newhash, 16) != 0) { | |
e87cc472 JP |
1267 | net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s\n", |
1268 | &iph->saddr, ntohs(th->source), | |
1269 | &iph->daddr, ntohs(th->dest), | |
1270 | genhash ? " tcp_v4_calc_md5_hash failed" | |
1271 | : ""); | |
a2a385d6 | 1272 | return true; |
cfb6eeb4 | 1273 | } |
a2a385d6 | 1274 | return false; |
cfb6eeb4 YH |
1275 | } |
1276 | ||
1277 | #endif | |
1278 | ||
72a3effa | 1279 | struct request_sock_ops tcp_request_sock_ops __read_mostly = { |
1da177e4 | 1280 | .family = PF_INET, |
2e6599cb | 1281 | .obj_size = sizeof(struct tcp_request_sock), |
72659ecc | 1282 | .rtx_syn_ack = tcp_v4_rtx_synack, |
60236fdd ACM |
1283 | .send_ack = tcp_v4_reqsk_send_ack, |
1284 | .destructor = tcp_v4_reqsk_destructor, | |
1da177e4 | 1285 | .send_reset = tcp_v4_send_reset, |
72659ecc | 1286 | .syn_ack_timeout = tcp_syn_ack_timeout, |
1da177e4 LT |
1287 | }; |
1288 | ||
cfb6eeb4 | 1289 | #ifdef CONFIG_TCP_MD5SIG |
b2e4b3de | 1290 | static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { |
cfb6eeb4 | 1291 | .md5_lookup = tcp_v4_reqsk_md5_lookup, |
e3afe7b7 | 1292 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
cfb6eeb4 | 1293 | }; |
b6332e6c | 1294 | #endif |
cfb6eeb4 | 1295 | |
168a8f58 JC |
1296 | static bool tcp_fastopen_check(struct sock *sk, struct sk_buff *skb, |
1297 | struct request_sock *req, | |
1298 | struct tcp_fastopen_cookie *foc, | |
1299 | struct tcp_fastopen_cookie *valid_foc) | |
1300 | { | |
1301 | bool skip_cookie = false; | |
1302 | struct fastopen_queue *fastopenq; | |
1303 | ||
1304 | if (likely(!fastopen_cookie_present(foc))) { | |
1305 | /* See include/net/tcp.h for the meaning of these knobs */ | |
1306 | if ((sysctl_tcp_fastopen & TFO_SERVER_ALWAYS) || | |
1307 | ((sysctl_tcp_fastopen & TFO_SERVER_COOKIE_NOT_REQD) && | |
1308 | (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq + 1))) | |
1309 | skip_cookie = true; /* no cookie to validate */ | |
1310 | else | |
1311 | return false; | |
1312 | } | |
1313 | fastopenq = inet_csk(sk)->icsk_accept_queue.fastopenq; | |
1314 | /* A FO option is present; bump the counter. */ | |
1315 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPFASTOPENPASSIVE); | |
1316 | ||
1317 | /* Make sure the listener has enabled fastopen, and we don't | |
1318 | * exceed the max # of pending TFO requests allowed before trying | |
1319 | * to validating the cookie in order to avoid burning CPU cycles | |
1320 | * unnecessarily. | |
1321 | * | |
1322 | * XXX (TFO) - The implication of checking the max_qlen before | |
1323 | * processing a cookie request is that clients can't differentiate | |
1324 | * between qlen overflow causing Fast Open to be disabled | |
1325 | * temporarily vs a server not supporting Fast Open at all. | |
1326 | */ | |
1327 | if ((sysctl_tcp_fastopen & TFO_SERVER_ENABLE) == 0 || | |
1328 | fastopenq == NULL || fastopenq->max_qlen == 0) | |
1329 | return false; | |
1330 | ||
1331 | if (fastopenq->qlen >= fastopenq->max_qlen) { | |
1332 | struct request_sock *req1; | |
1333 | spin_lock(&fastopenq->lock); | |
1334 | req1 = fastopenq->rskq_rst_head; | |
1335 | if ((req1 == NULL) || time_after(req1->expires, jiffies)) { | |
1336 | spin_unlock(&fastopenq->lock); | |
1337 | NET_INC_STATS_BH(sock_net(sk), | |
1338 | LINUX_MIB_TCPFASTOPENLISTENOVERFLOW); | |
1339 | /* Avoid bumping LINUX_MIB_TCPFASTOPENPASSIVEFAIL*/ | |
1340 | foc->len = -1; | |
1341 | return false; | |
1342 | } | |
1343 | fastopenq->rskq_rst_head = req1->dl_next; | |
1344 | fastopenq->qlen--; | |
1345 | spin_unlock(&fastopenq->lock); | |
1346 | reqsk_free(req1); | |
1347 | } | |
1348 | if (skip_cookie) { | |
1349 | tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->end_seq; | |
1350 | return true; | |
1351 | } | |
1352 | if (foc->len == TCP_FASTOPEN_COOKIE_SIZE) { | |
1353 | if ((sysctl_tcp_fastopen & TFO_SERVER_COOKIE_NOT_CHKED) == 0) { | |
1354 | tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr, valid_foc); | |
1355 | if ((valid_foc->len != TCP_FASTOPEN_COOKIE_SIZE) || | |
1356 | memcmp(&foc->val[0], &valid_foc->val[0], | |
1357 | TCP_FASTOPEN_COOKIE_SIZE) != 0) | |
1358 | return false; | |
1359 | valid_foc->len = -1; | |
1360 | } | |
1361 | /* Acknowledge the data received from the peer. */ | |
1362 | tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->end_seq; | |
1363 | return true; | |
1364 | } else if (foc->len == 0) { /* Client requesting a cookie */ | |
1365 | tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr, valid_foc); | |
1366 | NET_INC_STATS_BH(sock_net(sk), | |
1367 | LINUX_MIB_TCPFASTOPENCOOKIEREQD); | |
1368 | } else { | |
1369 | /* Client sent a cookie with wrong size. Treat it | |
1370 | * the same as invalid and return a valid one. | |
1371 | */ | |
1372 | tcp_fastopen_cookie_gen(ip_hdr(skb)->saddr, valid_foc); | |
1373 | } | |
1374 | return false; | |
1375 | } | |
1376 | ||
1377 | static int tcp_v4_conn_req_fastopen(struct sock *sk, | |
1378 | struct sk_buff *skb, | |
1379 | struct sk_buff *skb_synack, | |
1380 | struct request_sock *req, | |
1381 | struct request_values *rvp) | |
1382 | { | |
1383 | struct tcp_sock *tp = tcp_sk(sk); | |
1384 | struct request_sock_queue *queue = &inet_csk(sk)->icsk_accept_queue; | |
1385 | const struct inet_request_sock *ireq = inet_rsk(req); | |
1386 | struct sock *child; | |
016818d0 | 1387 | int err; |
168a8f58 JC |
1388 | |
1389 | req->retrans = 0; | |
1390 | req->sk = NULL; | |
1391 | ||
1392 | child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL); | |
1393 | if (child == NULL) { | |
1394 | NET_INC_STATS_BH(sock_net(sk), | |
1395 | LINUX_MIB_TCPFASTOPENPASSIVEFAIL); | |
1396 | kfree_skb(skb_synack); | |
1397 | return -1; | |
1398 | } | |
016818d0 NC |
1399 | err = ip_build_and_send_pkt(skb_synack, sk, ireq->loc_addr, |
1400 | ireq->rmt_addr, ireq->opt); | |
1401 | err = net_xmit_eval(err); | |
1402 | if (!err) | |
1403 | tcp_rsk(req)->snt_synack = tcp_time_stamp; | |
168a8f58 JC |
1404 | /* XXX (TFO) - is it ok to ignore error and continue? */ |
1405 | ||
1406 | spin_lock(&queue->fastopenq->lock); | |
1407 | queue->fastopenq->qlen++; | |
1408 | spin_unlock(&queue->fastopenq->lock); | |
1409 | ||
1410 | /* Initialize the child socket. Have to fix some values to take | |
1411 | * into account the child is a Fast Open socket and is created | |
1412 | * only out of the bits carried in the SYN packet. | |
1413 | */ | |
1414 | tp = tcp_sk(child); | |
1415 | ||
1416 | tp->fastopen_rsk = req; | |
1417 | /* Do a hold on the listner sk so that if the listener is being | |
1418 | * closed, the child that has been accepted can live on and still | |
1419 | * access listen_lock. | |
1420 | */ | |
1421 | sock_hold(sk); | |
1422 | tcp_rsk(req)->listener = sk; | |
1423 | ||
1424 | /* RFC1323: The window in SYN & SYN/ACK segments is never | |
1425 | * scaled. So correct it appropriately. | |
1426 | */ | |
1427 | tp->snd_wnd = ntohs(tcp_hdr(skb)->window); | |
1428 | ||
1429 | /* Activate the retrans timer so that SYNACK can be retransmitted. | |
1430 | * The request socket is not added to the SYN table of the parent | |
1431 | * because it's been added to the accept queue directly. | |
1432 | */ | |
1433 | inet_csk_reset_xmit_timer(child, ICSK_TIME_RETRANS, | |
1434 | TCP_TIMEOUT_INIT, TCP_RTO_MAX); | |
1435 | ||
1436 | /* Add the child socket directly into the accept queue */ | |
1437 | inet_csk_reqsk_queue_add(sk, req, child); | |
1438 | ||
1439 | /* Now finish processing the fastopen child socket. */ | |
1440 | inet_csk(child)->icsk_af_ops->rebuild_header(child); | |
1441 | tcp_init_congestion_control(child); | |
1442 | tcp_mtup_init(child); | |
1443 | tcp_init_buffer_space(child); | |
1444 | tcp_init_metrics(child); | |
1445 | ||
1446 | /* Queue the data carried in the SYN packet. We need to first | |
1447 | * bump skb's refcnt because the caller will attempt to free it. | |
1448 | * | |
1449 | * XXX (TFO) - we honor a zero-payload TFO request for now. | |
1450 | * (Any reason not to?) | |
1451 | */ | |
1452 | if (TCP_SKB_CB(skb)->end_seq == TCP_SKB_CB(skb)->seq + 1) { | |
1453 | /* Don't queue the skb if there is no payload in SYN. | |
1454 | * XXX (TFO) - How about SYN+FIN? | |
1455 | */ | |
1456 | tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq; | |
1457 | } else { | |
1458 | skb = skb_get(skb); | |
1459 | skb_dst_drop(skb); | |
1460 | __skb_pull(skb, tcp_hdr(skb)->doff * 4); | |
1461 | skb_set_owner_r(skb, child); | |
1462 | __skb_queue_tail(&child->sk_receive_queue, skb); | |
1463 | tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq; | |
1464 | } | |
1465 | sk->sk_data_ready(sk, 0); | |
1466 | bh_unlock_sock(child); | |
1467 | sock_put(child); | |
1468 | WARN_ON(req->sk == NULL); | |
1469 | return 0; | |
1470 | } | |
1471 | ||
1da177e4 LT |
1472 | int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
1473 | { | |
4957faad | 1474 | struct tcp_extend_values tmp_ext; |
1da177e4 | 1475 | struct tcp_options_received tmp_opt; |
cf533ea5 | 1476 | const u8 *hash_location; |
60236fdd | 1477 | struct request_sock *req; |
e6b4d113 | 1478 | struct inet_request_sock *ireq; |
4957faad | 1479 | struct tcp_sock *tp = tcp_sk(sk); |
e6b4d113 | 1480 | struct dst_entry *dst = NULL; |
eddc9ec5 ACM |
1481 | __be32 saddr = ip_hdr(skb)->saddr; |
1482 | __be32 daddr = ip_hdr(skb)->daddr; | |
1da177e4 | 1483 | __u32 isn = TCP_SKB_CB(skb)->when; |
a2a385d6 | 1484 | bool want_cookie = false; |
168a8f58 JC |
1485 | struct flowi4 fl4; |
1486 | struct tcp_fastopen_cookie foc = { .len = -1 }; | |
1487 | struct tcp_fastopen_cookie valid_foc = { .len = -1 }; | |
1488 | struct sk_buff *skb_synack; | |
1489 | int do_fastopen; | |
1da177e4 LT |
1490 | |
1491 | /* Never answer to SYNs send to broadcast or multicast */ | |
511c3f92 | 1492 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
1da177e4 LT |
1493 | goto drop; |
1494 | ||
1495 | /* TW buckets are converted to open requests without | |
1496 | * limitations, they conserve resources and peer is | |
1497 | * evidently real one. | |
1498 | */ | |
463c84b9 | 1499 | if (inet_csk_reqsk_queue_is_full(sk) && !isn) { |
946cedcc ED |
1500 | want_cookie = tcp_syn_flood_action(sk, skb, "TCP"); |
1501 | if (!want_cookie) | |
1502 | goto drop; | |
1da177e4 LT |
1503 | } |
1504 | ||
1505 | /* Accept backlog is full. If we have already queued enough | |
1506 | * of warm entries in syn queue, drop request. It is better than | |
1507 | * clogging syn queue with openreqs with exponentially increasing | |
1508 | * timeout. | |
1509 | */ | |
463c84b9 | 1510 | if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) |
1da177e4 LT |
1511 | goto drop; |
1512 | ||
ce4a7d0d | 1513 | req = inet_reqsk_alloc(&tcp_request_sock_ops); |
1da177e4 LT |
1514 | if (!req) |
1515 | goto drop; | |
1516 | ||
cfb6eeb4 YH |
1517 | #ifdef CONFIG_TCP_MD5SIG |
1518 | tcp_rsk(req)->af_specific = &tcp_request_sock_ipv4_ops; | |
1519 | #endif | |
1520 | ||
1da177e4 | 1521 | tcp_clear_options(&tmp_opt); |
bee7ca9e | 1522 | tmp_opt.mss_clamp = TCP_MSS_DEFAULT; |
4957faad | 1523 | tmp_opt.user_mss = tp->rx_opt.user_mss; |
168a8f58 JC |
1524 | tcp_parse_options(skb, &tmp_opt, &hash_location, 0, |
1525 | want_cookie ? NULL : &foc); | |
4957faad WAS |
1526 | |
1527 | if (tmp_opt.cookie_plus > 0 && | |
1528 | tmp_opt.saw_tstamp && | |
1529 | !tp->rx_opt.cookie_out_never && | |
1530 | (sysctl_tcp_cookie_size > 0 || | |
1531 | (tp->cookie_values != NULL && | |
1532 | tp->cookie_values->cookie_desired > 0))) { | |
1533 | u8 *c; | |
1534 | u32 *mess = &tmp_ext.cookie_bakery[COOKIE_DIGEST_WORDS]; | |
1535 | int l = tmp_opt.cookie_plus - TCPOLEN_COOKIE_BASE; | |
1536 | ||
1537 | if (tcp_cookie_generator(&tmp_ext.cookie_bakery[0]) != 0) | |
1538 | goto drop_and_release; | |
1539 | ||
1540 | /* Secret recipe starts with IP addresses */ | |
0eae88f3 ED |
1541 | *mess++ ^= (__force u32)daddr; |
1542 | *mess++ ^= (__force u32)saddr; | |
1da177e4 | 1543 | |
4957faad WAS |
1544 | /* plus variable length Initiator Cookie */ |
1545 | c = (u8 *)mess; | |
1546 | while (l-- > 0) | |
1547 | *c++ ^= *hash_location++; | |
1548 | ||
a2a385d6 | 1549 | want_cookie = false; /* not our kind of cookie */ |
4957faad WAS |
1550 | tmp_ext.cookie_out_never = 0; /* false */ |
1551 | tmp_ext.cookie_plus = tmp_opt.cookie_plus; | |
1552 | } else if (!tp->rx_opt.cookie_in_always) { | |
1553 | /* redundant indications, but ensure initialization. */ | |
1554 | tmp_ext.cookie_out_never = 1; /* true */ | |
1555 | tmp_ext.cookie_plus = 0; | |
1556 | } else { | |
1557 | goto drop_and_release; | |
1558 | } | |
1559 | tmp_ext.cookie_in_always = tp->rx_opt.cookie_in_always; | |
1da177e4 | 1560 | |
4dfc2817 | 1561 | if (want_cookie && !tmp_opt.saw_tstamp) |
1da177e4 | 1562 | tcp_clear_options(&tmp_opt); |
1da177e4 | 1563 | |
1da177e4 | 1564 | tmp_opt.tstamp_ok = tmp_opt.saw_tstamp; |
1da177e4 LT |
1565 | tcp_openreq_init(req, &tmp_opt, skb); |
1566 | ||
bb5b7c11 DM |
1567 | ireq = inet_rsk(req); |
1568 | ireq->loc_addr = daddr; | |
1569 | ireq->rmt_addr = saddr; | |
1570 | ireq->no_srccheck = inet_sk(sk)->transparent; | |
5dff747b | 1571 | ireq->opt = tcp_v4_save_options(skb); |
bb5b7c11 | 1572 | |
284904aa | 1573 | if (security_inet_conn_request(sk, skb, req)) |
bb5b7c11 | 1574 | goto drop_and_free; |
284904aa | 1575 | |
172d69e6 | 1576 | if (!want_cookie || tmp_opt.tstamp_ok) |
bd14b1b2 | 1577 | TCP_ECN_create_request(req, skb); |
1da177e4 LT |
1578 | |
1579 | if (want_cookie) { | |
1da177e4 | 1580 | isn = cookie_v4_init_sequence(sk, skb, &req->mss); |
172d69e6 | 1581 | req->cookie_ts = tmp_opt.tstamp_ok; |
1da177e4 | 1582 | } else if (!isn) { |
1da177e4 LT |
1583 | /* VJ's idea. We save last timestamp seen |
1584 | * from the destination in peer table, when entering | |
1585 | * state TIME-WAIT, and check against it before | |
1586 | * accepting new connection request. | |
1587 | * | |
1588 | * If "isn" is not zero, this request hit alive | |
1589 | * timewait bucket, so that all the necessary checks | |
1590 | * are made in the function processing timewait state. | |
1591 | */ | |
1592 | if (tmp_opt.saw_tstamp && | |
295ff7ed | 1593 | tcp_death_row.sysctl_tw_recycle && |
ba3f7f04 | 1594 | (dst = inet_csk_route_req(sk, &fl4, req)) != NULL && |
81166dd6 DM |
1595 | fl4.daddr == saddr) { |
1596 | if (!tcp_peer_is_proven(req, dst, true)) { | |
de0744af | 1597 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED); |
7cd04fa7 | 1598 | goto drop_and_release; |
1da177e4 LT |
1599 | } |
1600 | } | |
1601 | /* Kill the following clause, if you dislike this way. */ | |
1602 | else if (!sysctl_tcp_syncookies && | |
463c84b9 | 1603 | (sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) < |
1da177e4 | 1604 | (sysctl_max_syn_backlog >> 2)) && |
81166dd6 | 1605 | !tcp_peer_is_proven(req, dst, false)) { |
1da177e4 LT |
1606 | /* Without syncookies last quarter of |
1607 | * backlog is filled with destinations, | |
1608 | * proven to be alive. | |
1609 | * It means that we continue to communicate | |
1610 | * to destinations, already remembered | |
1611 | * to the moment of synflood. | |
1612 | */ | |
afd46503 | 1613 | LIMIT_NETDEBUG(KERN_DEBUG pr_fmt("drop open request from %pI4/%u\n"), |
673d57e7 | 1614 | &saddr, ntohs(tcp_hdr(skb)->source)); |
7cd04fa7 | 1615 | goto drop_and_release; |
1da177e4 LT |
1616 | } |
1617 | ||
a94f723d | 1618 | isn = tcp_v4_init_sequence(skb); |
1da177e4 | 1619 | } |
2e6599cb | 1620 | tcp_rsk(req)->snt_isn = isn; |
1da177e4 | 1621 | |
168a8f58 JC |
1622 | if (dst == NULL) { |
1623 | dst = inet_csk_route_req(sk, &fl4, req); | |
1624 | if (dst == NULL) | |
1625 | goto drop_and_free; | |
1626 | } | |
1627 | do_fastopen = tcp_fastopen_check(sk, skb, req, &foc, &valid_foc); | |
1628 | ||
1629 | /* We don't call tcp_v4_send_synack() directly because we need | |
1630 | * to make sure a child socket can be created successfully before | |
1631 | * sending back synack! | |
1632 | * | |
1633 | * XXX (TFO) - Ideally one would simply call tcp_v4_send_synack() | |
1634 | * (or better yet, call tcp_send_synack() in the child context | |
1635 | * directly, but will have to fix bunch of other code first) | |
1636 | * after syn_recv_sock() except one will need to first fix the | |
1637 | * latter to remove its dependency on the current implementation | |
1638 | * of tcp_v4_send_synack()->tcp_select_initial_window(). | |
1639 | */ | |
1640 | skb_synack = tcp_make_synack(sk, dst, req, | |
1641 | (struct request_values *)&tmp_ext, | |
1642 | fastopen_cookie_present(&valid_foc) ? &valid_foc : NULL); | |
1643 | ||
1644 | if (skb_synack) { | |
1645 | __tcp_v4_send_check(skb_synack, ireq->loc_addr, ireq->rmt_addr); | |
1646 | skb_set_queue_mapping(skb_synack, skb_get_queue_mapping(skb)); | |
1647 | } else | |
1648 | goto drop_and_free; | |
1649 | ||
1650 | if (likely(!do_fastopen)) { | |
1651 | int err; | |
1652 | err = ip_build_and_send_pkt(skb_synack, sk, ireq->loc_addr, | |
1653 | ireq->rmt_addr, ireq->opt); | |
1654 | err = net_xmit_eval(err); | |
1655 | if (err || want_cookie) | |
1656 | goto drop_and_free; | |
1657 | ||
016818d0 | 1658 | tcp_rsk(req)->snt_synack = tcp_time_stamp; |
168a8f58 JC |
1659 | tcp_rsk(req)->listener = NULL; |
1660 | /* Add the request_sock to the SYN table */ | |
1661 | inet_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); | |
1662 | if (fastopen_cookie_present(&foc) && foc.len != 0) | |
1663 | NET_INC_STATS_BH(sock_net(sk), | |
1664 | LINUX_MIB_TCPFASTOPENPASSIVEFAIL); | |
1665 | } else if (tcp_v4_conn_req_fastopen(sk, skb, skb_synack, req, | |
1666 | (struct request_values *)&tmp_ext)) | |
1da177e4 LT |
1667 | goto drop_and_free; |
1668 | ||
1da177e4 LT |
1669 | return 0; |
1670 | ||
7cd04fa7 DL |
1671 | drop_and_release: |
1672 | dst_release(dst); | |
1da177e4 | 1673 | drop_and_free: |
60236fdd | 1674 | reqsk_free(req); |
1da177e4 | 1675 | drop: |
1da177e4 LT |
1676 | return 0; |
1677 | } | |
4bc2f18b | 1678 | EXPORT_SYMBOL(tcp_v4_conn_request); |
1da177e4 LT |
1679 | |
1680 | ||
1681 | /* | |
1682 | * The three way handshake has completed - we got a valid synack - | |
1683 | * now create the new socket. | |
1684 | */ | |
1685 | struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, | |
60236fdd | 1686 | struct request_sock *req, |
1da177e4 LT |
1687 | struct dst_entry *dst) |
1688 | { | |
2e6599cb | 1689 | struct inet_request_sock *ireq; |
1da177e4 LT |
1690 | struct inet_sock *newinet; |
1691 | struct tcp_sock *newtp; | |
1692 | struct sock *newsk; | |
cfb6eeb4 YH |
1693 | #ifdef CONFIG_TCP_MD5SIG |
1694 | struct tcp_md5sig_key *key; | |
1695 | #endif | |
f6d8bd05 | 1696 | struct ip_options_rcu *inet_opt; |
1da177e4 LT |
1697 | |
1698 | if (sk_acceptq_is_full(sk)) | |
1699 | goto exit_overflow; | |
1700 | ||
1da177e4 LT |
1701 | newsk = tcp_create_openreq_child(sk, req, skb); |
1702 | if (!newsk) | |
093d2823 | 1703 | goto exit_nonewsk; |
1da177e4 | 1704 | |
bcd76111 | 1705 | newsk->sk_gso_type = SKB_GSO_TCPV4; |
fae6ef87 | 1706 | inet_sk_rx_dst_set(newsk, skb); |
1da177e4 LT |
1707 | |
1708 | newtp = tcp_sk(newsk); | |
1709 | newinet = inet_sk(newsk); | |
2e6599cb | 1710 | ireq = inet_rsk(req); |
c720c7e8 ED |
1711 | newinet->inet_daddr = ireq->rmt_addr; |
1712 | newinet->inet_rcv_saddr = ireq->loc_addr; | |
1713 | newinet->inet_saddr = ireq->loc_addr; | |
f6d8bd05 ED |
1714 | inet_opt = ireq->opt; |
1715 | rcu_assign_pointer(newinet->inet_opt, inet_opt); | |
2e6599cb | 1716 | ireq->opt = NULL; |
463c84b9 | 1717 | newinet->mc_index = inet_iif(skb); |
eddc9ec5 | 1718 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
4c507d28 | 1719 | newinet->rcv_tos = ip_hdr(skb)->tos; |
d83d8461 | 1720 | inet_csk(newsk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
1721 | if (inet_opt) |
1722 | inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
c720c7e8 | 1723 | newinet->inet_id = newtp->write_seq ^ jiffies; |
1da177e4 | 1724 | |
dfd25fff ED |
1725 | if (!dst) { |
1726 | dst = inet_csk_route_child_sock(sk, newsk, req); | |
1727 | if (!dst) | |
1728 | goto put_and_exit; | |
1729 | } else { | |
1730 | /* syncookie case : see end of cookie_v4_check() */ | |
1731 | } | |
0e734419 DM |
1732 | sk_setup_caps(newsk, dst); |
1733 | ||
5d424d5a | 1734 | tcp_mtup_init(newsk); |
1da177e4 | 1735 | tcp_sync_mss(newsk, dst_mtu(dst)); |
0dbaee3b | 1736 | newtp->advmss = dst_metric_advmss(dst); |
f5fff5dc TQ |
1737 | if (tcp_sk(sk)->rx_opt.user_mss && |
1738 | tcp_sk(sk)->rx_opt.user_mss < newtp->advmss) | |
1739 | newtp->advmss = tcp_sk(sk)->rx_opt.user_mss; | |
1740 | ||
1da177e4 | 1741 | tcp_initialize_rcv_mss(newsk); |
623df484 | 1742 | tcp_synack_rtt_meas(newsk, req); |
9ad7c049 | 1743 | newtp->total_retrans = req->retrans; |
1da177e4 | 1744 | |
cfb6eeb4 YH |
1745 | #ifdef CONFIG_TCP_MD5SIG |
1746 | /* Copy over the MD5 key from the original socket */ | |
a915da9b ED |
1747 | key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&newinet->inet_daddr, |
1748 | AF_INET); | |
c720c7e8 | 1749 | if (key != NULL) { |
cfb6eeb4 YH |
1750 | /* |
1751 | * We're using one, so create a matching key | |
1752 | * on the newsk structure. If we fail to get | |
1753 | * memory, then we end up not copying the key | |
1754 | * across. Shucks. | |
1755 | */ | |
a915da9b ED |
1756 | tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newinet->inet_daddr, |
1757 | AF_INET, key->key, key->keylen, GFP_ATOMIC); | |
a465419b | 1758 | sk_nocaps_add(newsk, NETIF_F_GSO_MASK); |
cfb6eeb4 YH |
1759 | } |
1760 | #endif | |
1761 | ||
0e734419 DM |
1762 | if (__inet_inherit_port(sk, newsk) < 0) |
1763 | goto put_and_exit; | |
9327f705 | 1764 | __inet_hash_nolisten(newsk, NULL); |
1da177e4 LT |
1765 | |
1766 | return newsk; | |
1767 | ||
1768 | exit_overflow: | |
de0744af | 1769 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
093d2823 BS |
1770 | exit_nonewsk: |
1771 | dst_release(dst); | |
1da177e4 | 1772 | exit: |
de0744af | 1773 | NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS); |
1da177e4 | 1774 | return NULL; |
0e734419 | 1775 | put_and_exit: |
709e8697 | 1776 | tcp_clear_xmit_timers(newsk); |
d8a6e65f | 1777 | tcp_cleanup_congestion_control(newsk); |
918eb399 | 1778 | bh_unlock_sock(newsk); |
0e734419 DM |
1779 | sock_put(newsk); |
1780 | goto exit; | |
1da177e4 | 1781 | } |
4bc2f18b | 1782 | EXPORT_SYMBOL(tcp_v4_syn_recv_sock); |
1da177e4 LT |
1783 | |
1784 | static struct sock *tcp_v4_hnd_req(struct sock *sk, struct sk_buff *skb) | |
1785 | { | |
aa8223c7 | 1786 | struct tcphdr *th = tcp_hdr(skb); |
eddc9ec5 | 1787 | const struct iphdr *iph = ip_hdr(skb); |
1da177e4 | 1788 | struct sock *nsk; |
60236fdd | 1789 | struct request_sock **prev; |
1da177e4 | 1790 | /* Find possible connection requests. */ |
463c84b9 ACM |
1791 | struct request_sock *req = inet_csk_search_req(sk, &prev, th->source, |
1792 | iph->saddr, iph->daddr); | |
1da177e4 | 1793 | if (req) |
8336886f | 1794 | return tcp_check_req(sk, skb, req, prev, false); |
1da177e4 | 1795 | |
3b1e0a65 | 1796 | nsk = inet_lookup_established(sock_net(sk), &tcp_hashinfo, iph->saddr, |
c67499c0 | 1797 | th->source, iph->daddr, th->dest, inet_iif(skb)); |
1da177e4 LT |
1798 | |
1799 | if (nsk) { | |
1800 | if (nsk->sk_state != TCP_TIME_WAIT) { | |
1801 | bh_lock_sock(nsk); | |
1802 | return nsk; | |
1803 | } | |
9469c7b4 | 1804 | inet_twsk_put(inet_twsk(nsk)); |
1da177e4 LT |
1805 | return NULL; |
1806 | } | |
1807 | ||
1808 | #ifdef CONFIG_SYN_COOKIES | |
af9b4738 | 1809 | if (!th->syn) |
1da177e4 LT |
1810 | sk = cookie_v4_check(sk, skb, &(IPCB(skb)->opt)); |
1811 | #endif | |
1812 | return sk; | |
1813 | } | |
1814 | ||
b51655b9 | 1815 | static __sum16 tcp_v4_checksum_init(struct sk_buff *skb) |
1da177e4 | 1816 | { |
eddc9ec5 ACM |
1817 | const struct iphdr *iph = ip_hdr(skb); |
1818 | ||
84fa7933 | 1819 | if (skb->ip_summed == CHECKSUM_COMPLETE) { |
eddc9ec5 ACM |
1820 | if (!tcp_v4_check(skb->len, iph->saddr, |
1821 | iph->daddr, skb->csum)) { | |
fb286bb2 | 1822 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
1da177e4 | 1823 | return 0; |
fb286bb2 | 1824 | } |
1da177e4 | 1825 | } |
fb286bb2 | 1826 | |
eddc9ec5 | 1827 | skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, |
fb286bb2 HX |
1828 | skb->len, IPPROTO_TCP, 0); |
1829 | ||
1da177e4 | 1830 | if (skb->len <= 76) { |
fb286bb2 | 1831 | return __skb_checksum_complete(skb); |
1da177e4 LT |
1832 | } |
1833 | return 0; | |
1834 | } | |
1835 | ||
1836 | ||
1837 | /* The socket must have it's spinlock held when we get | |
1838 | * here. | |
1839 | * | |
1840 | * We have a potential double-lock case here, so even when | |
1841 | * doing backlog processing we use the BH locking scheme. | |
1842 | * This is because we cannot sleep with the original spinlock | |
1843 | * held. | |
1844 | */ | |
1845 | int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) | |
1846 | { | |
cfb6eeb4 YH |
1847 | struct sock *rsk; |
1848 | #ifdef CONFIG_TCP_MD5SIG | |
1849 | /* | |
1850 | * We really want to reject the packet as early as possible | |
1851 | * if: | |
1852 | * o We're expecting an MD5'd packet and this is no MD5 tcp option | |
1853 | * o There is an MD5 option and we're not expecting one | |
1854 | */ | |
7174259e | 1855 | if (tcp_v4_inbound_md5_hash(sk, skb)) |
cfb6eeb4 YH |
1856 | goto discard; |
1857 | #endif | |
1858 | ||
1da177e4 | 1859 | if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ |
404e0a8b ED |
1860 | struct dst_entry *dst = sk->sk_rx_dst; |
1861 | ||
bdeab991 | 1862 | sock_rps_save_rxhash(sk, skb); |
404e0a8b | 1863 | if (dst) { |
505fbcf0 ED |
1864 | if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || |
1865 | dst->ops->check(dst, 0) == NULL) { | |
92101b3b DM |
1866 | dst_release(dst); |
1867 | sk->sk_rx_dst = NULL; | |
1868 | } | |
1869 | } | |
aa8223c7 | 1870 | if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len)) { |
cfb6eeb4 | 1871 | rsk = sk; |
1da177e4 | 1872 | goto reset; |
cfb6eeb4 | 1873 | } |
1da177e4 LT |
1874 | return 0; |
1875 | } | |
1876 | ||
ab6a5bb6 | 1877 | if (skb->len < tcp_hdrlen(skb) || tcp_checksum_complete(skb)) |
1da177e4 LT |
1878 | goto csum_err; |
1879 | ||
1880 | if (sk->sk_state == TCP_LISTEN) { | |
1881 | struct sock *nsk = tcp_v4_hnd_req(sk, skb); | |
1882 | if (!nsk) | |
1883 | goto discard; | |
1884 | ||
1885 | if (nsk != sk) { | |
bdeab991 | 1886 | sock_rps_save_rxhash(nsk, skb); |
cfb6eeb4 YH |
1887 | if (tcp_child_process(sk, nsk, skb)) { |
1888 | rsk = nsk; | |
1da177e4 | 1889 | goto reset; |
cfb6eeb4 | 1890 | } |
1da177e4 LT |
1891 | return 0; |
1892 | } | |
ca55158c | 1893 | } else |
bdeab991 | 1894 | sock_rps_save_rxhash(sk, skb); |
ca55158c | 1895 | |
aa8223c7 | 1896 | if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len)) { |
cfb6eeb4 | 1897 | rsk = sk; |
1da177e4 | 1898 | goto reset; |
cfb6eeb4 | 1899 | } |
1da177e4 LT |
1900 | return 0; |
1901 | ||
1902 | reset: | |
cfb6eeb4 | 1903 | tcp_v4_send_reset(rsk, skb); |
1da177e4 LT |
1904 | discard: |
1905 | kfree_skb(skb); | |
1906 | /* Be careful here. If this function gets more complicated and | |
1907 | * gcc suffers from register pressure on the x86, sk (in %ebx) | |
1908 | * might be destroyed here. This current version compiles correctly, | |
1909 | * but you have been warned. | |
1910 | */ | |
1911 | return 0; | |
1912 | ||
1913 | csum_err: | |
63231bdd | 1914 | TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS); |
1da177e4 LT |
1915 | goto discard; |
1916 | } | |
4bc2f18b | 1917 | EXPORT_SYMBOL(tcp_v4_do_rcv); |
1da177e4 | 1918 | |
160eb5a6 | 1919 | void tcp_v4_early_demux(struct sk_buff *skb) |
41063e9d DM |
1920 | { |
1921 | struct net *net = dev_net(skb->dev); | |
1922 | const struct iphdr *iph; | |
1923 | const struct tcphdr *th; | |
1924 | struct sock *sk; | |
41063e9d | 1925 | |
41063e9d | 1926 | if (skb->pkt_type != PACKET_HOST) |
160eb5a6 | 1927 | return; |
41063e9d DM |
1928 | |
1929 | if (!pskb_may_pull(skb, ip_hdrlen(skb) + sizeof(struct tcphdr))) | |
160eb5a6 | 1930 | return; |
41063e9d DM |
1931 | |
1932 | iph = ip_hdr(skb); | |
1933 | th = (struct tcphdr *) ((char *)iph + ip_hdrlen(skb)); | |
1934 | ||
1935 | if (th->doff < sizeof(struct tcphdr) / 4) | |
160eb5a6 | 1936 | return; |
41063e9d | 1937 | |
41063e9d DM |
1938 | sk = __inet_lookup_established(net, &tcp_hashinfo, |
1939 | iph->saddr, th->source, | |
7011d085 | 1940 | iph->daddr, ntohs(th->dest), |
9cb429d6 | 1941 | skb->skb_iif); |
41063e9d DM |
1942 | if (sk) { |
1943 | skb->sk = sk; | |
1944 | skb->destructor = sock_edemux; | |
1945 | if (sk->sk_state != TCP_TIME_WAIT) { | |
1946 | struct dst_entry *dst = sk->sk_rx_dst; | |
505fbcf0 | 1947 | |
41063e9d DM |
1948 | if (dst) |
1949 | dst = dst_check(dst, 0); | |
92101b3b | 1950 | if (dst && |
505fbcf0 | 1951 | inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) |
92101b3b | 1952 | skb_dst_set_noref(skb, dst); |
41063e9d DM |
1953 | } |
1954 | } | |
41063e9d DM |
1955 | } |
1956 | ||
1da177e4 LT |
1957 | /* |
1958 | * From tcp_input.c | |
1959 | */ | |
1960 | ||
1961 | int tcp_v4_rcv(struct sk_buff *skb) | |
1962 | { | |
eddc9ec5 | 1963 | const struct iphdr *iph; |
cf533ea5 | 1964 | const struct tcphdr *th; |
1da177e4 LT |
1965 | struct sock *sk; |
1966 | int ret; | |
a86b1e30 | 1967 | struct net *net = dev_net(skb->dev); |
1da177e4 LT |
1968 | |
1969 | if (skb->pkt_type != PACKET_HOST) | |
1970 | goto discard_it; | |
1971 | ||
1972 | /* Count it even if it's bad */ | |
63231bdd | 1973 | TCP_INC_STATS_BH(net, TCP_MIB_INSEGS); |
1da177e4 LT |
1974 | |
1975 | if (!pskb_may_pull(skb, sizeof(struct tcphdr))) | |
1976 | goto discard_it; | |
1977 | ||
aa8223c7 | 1978 | th = tcp_hdr(skb); |
1da177e4 LT |
1979 | |
1980 | if (th->doff < sizeof(struct tcphdr) / 4) | |
1981 | goto bad_packet; | |
1982 | if (!pskb_may_pull(skb, th->doff * 4)) | |
1983 | goto discard_it; | |
1984 | ||
1985 | /* An explanation is required here, I think. | |
1986 | * Packet length and doff are validated by header prediction, | |
caa20d9a | 1987 | * provided case of th->doff==0 is eliminated. |
1da177e4 | 1988 | * So, we defer the checks. */ |
60476372 | 1989 | if (!skb_csum_unnecessary(skb) && tcp_v4_checksum_init(skb)) |
1da177e4 LT |
1990 | goto bad_packet; |
1991 | ||
aa8223c7 | 1992 | th = tcp_hdr(skb); |
eddc9ec5 | 1993 | iph = ip_hdr(skb); |
1da177e4 LT |
1994 | TCP_SKB_CB(skb)->seq = ntohl(th->seq); |
1995 | TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + | |
1996 | skb->len - th->doff * 4); | |
1997 | TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); | |
1998 | TCP_SKB_CB(skb)->when = 0; | |
b82d1bb4 | 1999 | TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph); |
1da177e4 LT |
2000 | TCP_SKB_CB(skb)->sacked = 0; |
2001 | ||
9a1f27c4 | 2002 | sk = __inet_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest); |
1da177e4 LT |
2003 | if (!sk) |
2004 | goto no_tcp_socket; | |
2005 | ||
bb134d5d ED |
2006 | process: |
2007 | if (sk->sk_state == TCP_TIME_WAIT) | |
2008 | goto do_time_wait; | |
2009 | ||
6cce09f8 ED |
2010 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
2011 | NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); | |
d218d111 | 2012 | goto discard_and_relse; |
6cce09f8 | 2013 | } |
d218d111 | 2014 | |
1da177e4 LT |
2015 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
2016 | goto discard_and_relse; | |
b59c2701 | 2017 | nf_reset(skb); |
1da177e4 | 2018 | |
fda9ef5d | 2019 | if (sk_filter(sk, skb)) |
1da177e4 LT |
2020 | goto discard_and_relse; |
2021 | ||
2022 | skb->dev = NULL; | |
2023 | ||
c6366184 | 2024 | bh_lock_sock_nested(sk); |
1da177e4 LT |
2025 | ret = 0; |
2026 | if (!sock_owned_by_user(sk)) { | |
1a2449a8 CL |
2027 | #ifdef CONFIG_NET_DMA |
2028 | struct tcp_sock *tp = tcp_sk(sk); | |
2029 | if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list) | |
a2bd1140 | 2030 | tp->ucopy.dma_chan = net_dma_find_channel(); |
1a2449a8 | 2031 | if (tp->ucopy.dma_chan) |
1da177e4 | 2032 | ret = tcp_v4_do_rcv(sk, skb); |
1a2449a8 CL |
2033 | else |
2034 | #endif | |
2035 | { | |
2036 | if (!tcp_prequeue(sk, skb)) | |
ae8d7f88 | 2037 | ret = tcp_v4_do_rcv(sk, skb); |
1a2449a8 | 2038 | } |
da882c1f ED |
2039 | } else if (unlikely(sk_add_backlog(sk, skb, |
2040 | sk->sk_rcvbuf + sk->sk_sndbuf))) { | |
6b03a53a | 2041 | bh_unlock_sock(sk); |
6cce09f8 | 2042 | NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP); |
6b03a53a ZY |
2043 | goto discard_and_relse; |
2044 | } | |
1da177e4 LT |
2045 | bh_unlock_sock(sk); |
2046 | ||
2047 | sock_put(sk); | |
2048 | ||
2049 | return ret; | |
2050 | ||
2051 | no_tcp_socket: | |
2052 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) | |
2053 | goto discard_it; | |
2054 | ||
2055 | if (skb->len < (th->doff << 2) || tcp_checksum_complete(skb)) { | |
2056 | bad_packet: | |
63231bdd | 2057 | TCP_INC_STATS_BH(net, TCP_MIB_INERRS); |
1da177e4 | 2058 | } else { |
cfb6eeb4 | 2059 | tcp_v4_send_reset(NULL, skb); |
1da177e4 LT |
2060 | } |
2061 | ||
2062 | discard_it: | |
2063 | /* Discard frame. */ | |
2064 | kfree_skb(skb); | |
e905a9ed | 2065 | return 0; |
1da177e4 LT |
2066 | |
2067 | discard_and_relse: | |
2068 | sock_put(sk); | |
2069 | goto discard_it; | |
2070 | ||
2071 | do_time_wait: | |
2072 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { | |
9469c7b4 | 2073 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
2074 | goto discard_it; |
2075 | } | |
2076 | ||
2077 | if (skb->len < (th->doff << 2) || tcp_checksum_complete(skb)) { | |
63231bdd | 2078 | TCP_INC_STATS_BH(net, TCP_MIB_INERRS); |
9469c7b4 | 2079 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
2080 | goto discard_it; |
2081 | } | |
9469c7b4 | 2082 | switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { |
1da177e4 | 2083 | case TCP_TW_SYN: { |
c346dca1 | 2084 | struct sock *sk2 = inet_lookup_listener(dev_net(skb->dev), |
c67499c0 | 2085 | &tcp_hashinfo, |
eddc9ec5 | 2086 | iph->daddr, th->dest, |
463c84b9 | 2087 | inet_iif(skb)); |
1da177e4 | 2088 | if (sk2) { |
9469c7b4 YH |
2089 | inet_twsk_deschedule(inet_twsk(sk), &tcp_death_row); |
2090 | inet_twsk_put(inet_twsk(sk)); | |
1da177e4 LT |
2091 | sk = sk2; |
2092 | goto process; | |
2093 | } | |
2094 | /* Fall through to ACK */ | |
2095 | } | |
2096 | case TCP_TW_ACK: | |
2097 | tcp_v4_timewait_ack(sk, skb); | |
2098 | break; | |
2099 | case TCP_TW_RST: | |
2100 | goto no_tcp_socket; | |
2101 | case TCP_TW_SUCCESS:; | |
2102 | } | |
2103 | goto discard_it; | |
2104 | } | |
2105 | ||
ccb7c410 DM |
2106 | static struct timewait_sock_ops tcp_timewait_sock_ops = { |
2107 | .twsk_obj_size = sizeof(struct tcp_timewait_sock), | |
2108 | .twsk_unique = tcp_twsk_unique, | |
2109 | .twsk_destructor= tcp_twsk_destructor, | |
ccb7c410 | 2110 | }; |
1da177e4 | 2111 | |
63d02d15 | 2112 | void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb) |
5d299f3d ED |
2113 | { |
2114 | struct dst_entry *dst = skb_dst(skb); | |
2115 | ||
2116 | dst_hold(dst); | |
2117 | sk->sk_rx_dst = dst; | |
2118 | inet_sk(sk)->rx_dst_ifindex = skb->skb_iif; | |
2119 | } | |
63d02d15 | 2120 | EXPORT_SYMBOL(inet_sk_rx_dst_set); |
5d299f3d | 2121 | |
3b401a81 | 2122 | const struct inet_connection_sock_af_ops ipv4_specific = { |
543d9cfe ACM |
2123 | .queue_xmit = ip_queue_xmit, |
2124 | .send_check = tcp_v4_send_check, | |
2125 | .rebuild_header = inet_sk_rebuild_header, | |
5d299f3d | 2126 | .sk_rx_dst_set = inet_sk_rx_dst_set, |
543d9cfe ACM |
2127 | .conn_request = tcp_v4_conn_request, |
2128 | .syn_recv_sock = tcp_v4_syn_recv_sock, | |
543d9cfe ACM |
2129 | .net_header_len = sizeof(struct iphdr), |
2130 | .setsockopt = ip_setsockopt, | |
2131 | .getsockopt = ip_getsockopt, | |
2132 | .addr2sockaddr = inet_csk_addr2sockaddr, | |
2133 | .sockaddr_len = sizeof(struct sockaddr_in), | |
ab1e0a13 | 2134 | .bind_conflict = inet_csk_bind_conflict, |
3fdadf7d | 2135 | #ifdef CONFIG_COMPAT |
543d9cfe ACM |
2136 | .compat_setsockopt = compat_ip_setsockopt, |
2137 | .compat_getsockopt = compat_ip_getsockopt, | |
3fdadf7d | 2138 | #endif |
1da177e4 | 2139 | }; |
4bc2f18b | 2140 | EXPORT_SYMBOL(ipv4_specific); |
1da177e4 | 2141 | |
cfb6eeb4 | 2142 | #ifdef CONFIG_TCP_MD5SIG |
b2e4b3de | 2143 | static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = { |
cfb6eeb4 | 2144 | .md5_lookup = tcp_v4_md5_lookup, |
49a72dfb | 2145 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
cfb6eeb4 | 2146 | .md5_parse = tcp_v4_parse_md5_keys, |
cfb6eeb4 | 2147 | }; |
b6332e6c | 2148 | #endif |
cfb6eeb4 | 2149 | |
1da177e4 LT |
2150 | /* NOTE: A lot of things set to zero explicitly by call to |
2151 | * sk_alloc() so need not be done here. | |
2152 | */ | |
2153 | static int tcp_v4_init_sock(struct sock *sk) | |
2154 | { | |
6687e988 | 2155 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 | 2156 | |
900f65d3 | 2157 | tcp_init_sock(sk); |
1da177e4 | 2158 | |
8292a17a | 2159 | icsk->icsk_af_ops = &ipv4_specific; |
900f65d3 | 2160 | |
cfb6eeb4 | 2161 | #ifdef CONFIG_TCP_MD5SIG |
ac807fa8 | 2162 | tcp_sk(sk)->af_specific = &tcp_sock_ipv4_specific; |
cfb6eeb4 | 2163 | #endif |
1da177e4 | 2164 | |
1da177e4 LT |
2165 | return 0; |
2166 | } | |
2167 | ||
7d06b2e0 | 2168 | void tcp_v4_destroy_sock(struct sock *sk) |
1da177e4 LT |
2169 | { |
2170 | struct tcp_sock *tp = tcp_sk(sk); | |
2171 | ||
2172 | tcp_clear_xmit_timers(sk); | |
2173 | ||
6687e988 | 2174 | tcp_cleanup_congestion_control(sk); |
317a76f9 | 2175 | |
1da177e4 | 2176 | /* Cleanup up the write buffer. */ |
fe067e8a | 2177 | tcp_write_queue_purge(sk); |
1da177e4 LT |
2178 | |
2179 | /* Cleans up our, hopefully empty, out_of_order_queue. */ | |
e905a9ed | 2180 | __skb_queue_purge(&tp->out_of_order_queue); |
1da177e4 | 2181 | |
cfb6eeb4 YH |
2182 | #ifdef CONFIG_TCP_MD5SIG |
2183 | /* Clean up the MD5 key list, if any */ | |
2184 | if (tp->md5sig_info) { | |
a915da9b | 2185 | tcp_clear_md5_list(sk); |
a8afca03 | 2186 | kfree_rcu(tp->md5sig_info, rcu); |
cfb6eeb4 YH |
2187 | tp->md5sig_info = NULL; |
2188 | } | |
2189 | #endif | |
2190 | ||
1a2449a8 CL |
2191 | #ifdef CONFIG_NET_DMA |
2192 | /* Cleans up our sk_async_wait_queue */ | |
e905a9ed | 2193 | __skb_queue_purge(&sk->sk_async_wait_queue); |
1a2449a8 CL |
2194 | #endif |
2195 | ||
1da177e4 LT |
2196 | /* Clean prequeue, it must be empty really */ |
2197 | __skb_queue_purge(&tp->ucopy.prequeue); | |
2198 | ||
2199 | /* Clean up a referenced TCP bind bucket. */ | |
463c84b9 | 2200 | if (inet_csk(sk)->icsk_bind_hash) |
ab1e0a13 | 2201 | inet_put_port(sk); |
1da177e4 | 2202 | |
435cf559 WAS |
2203 | /* TCP Cookie Transactions */ |
2204 | if (tp->cookie_values != NULL) { | |
2205 | kref_put(&tp->cookie_values->kref, | |
2206 | tcp_cookie_values_release); | |
2207 | tp->cookie_values = NULL; | |
2208 | } | |
168a8f58 | 2209 | BUG_ON(tp->fastopen_rsk != NULL); |
435cf559 | 2210 | |
cf60af03 YC |
2211 | /* If socket is aborted during connect operation */ |
2212 | tcp_free_fastopen_req(tp); | |
2213 | ||
180d8cd9 | 2214 | sk_sockets_allocated_dec(sk); |
d1a4c0b3 | 2215 | sock_release_memcg(sk); |
1da177e4 | 2216 | } |
1da177e4 LT |
2217 | EXPORT_SYMBOL(tcp_v4_destroy_sock); |
2218 | ||
2219 | #ifdef CONFIG_PROC_FS | |
2220 | /* Proc filesystem TCP sock list dumping. */ | |
2221 | ||
3ab5aee7 | 2222 | static inline struct inet_timewait_sock *tw_head(struct hlist_nulls_head *head) |
1da177e4 | 2223 | { |
3ab5aee7 | 2224 | return hlist_nulls_empty(head) ? NULL : |
8feaf0c0 | 2225 | list_entry(head->first, struct inet_timewait_sock, tw_node); |
1da177e4 LT |
2226 | } |
2227 | ||
8feaf0c0 | 2228 | static inline struct inet_timewait_sock *tw_next(struct inet_timewait_sock *tw) |
1da177e4 | 2229 | { |
3ab5aee7 ED |
2230 | return !is_a_nulls(tw->tw_node.next) ? |
2231 | hlist_nulls_entry(tw->tw_node.next, typeof(*tw), tw_node) : NULL; | |
1da177e4 LT |
2232 | } |
2233 | ||
a8b690f9 TH |
2234 | /* |
2235 | * Get next listener socket follow cur. If cur is NULL, get first socket | |
2236 | * starting from bucket given in st->bucket; when st->bucket is zero the | |
2237 | * very first socket in the hash table is returned. | |
2238 | */ | |
1da177e4 LT |
2239 | static void *listening_get_next(struct seq_file *seq, void *cur) |
2240 | { | |
463c84b9 | 2241 | struct inet_connection_sock *icsk; |
c25eb3bf | 2242 | struct hlist_nulls_node *node; |
1da177e4 | 2243 | struct sock *sk = cur; |
5caea4ea | 2244 | struct inet_listen_hashbucket *ilb; |
5799de0b | 2245 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2246 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2247 | |
2248 | if (!sk) { | |
a8b690f9 | 2249 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
5caea4ea | 2250 | spin_lock_bh(&ilb->lock); |
c25eb3bf | 2251 | sk = sk_nulls_head(&ilb->head); |
a8b690f9 | 2252 | st->offset = 0; |
1da177e4 LT |
2253 | goto get_sk; |
2254 | } | |
5caea4ea | 2255 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
1da177e4 | 2256 | ++st->num; |
a8b690f9 | 2257 | ++st->offset; |
1da177e4 LT |
2258 | |
2259 | if (st->state == TCP_SEQ_STATE_OPENREQ) { | |
60236fdd | 2260 | struct request_sock *req = cur; |
1da177e4 | 2261 | |
72a3effa | 2262 | icsk = inet_csk(st->syn_wait_sk); |
1da177e4 LT |
2263 | req = req->dl_next; |
2264 | while (1) { | |
2265 | while (req) { | |
bdccc4ca | 2266 | if (req->rsk_ops->family == st->family) { |
1da177e4 LT |
2267 | cur = req; |
2268 | goto out; | |
2269 | } | |
2270 | req = req->dl_next; | |
2271 | } | |
72a3effa | 2272 | if (++st->sbucket >= icsk->icsk_accept_queue.listen_opt->nr_table_entries) |
1da177e4 LT |
2273 | break; |
2274 | get_req: | |
463c84b9 | 2275 | req = icsk->icsk_accept_queue.listen_opt->syn_table[st->sbucket]; |
1da177e4 | 2276 | } |
1bde5ac4 | 2277 | sk = sk_nulls_next(st->syn_wait_sk); |
1da177e4 | 2278 | st->state = TCP_SEQ_STATE_LISTENING; |
463c84b9 | 2279 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
1da177e4 | 2280 | } else { |
e905a9ed | 2281 | icsk = inet_csk(sk); |
463c84b9 ACM |
2282 | read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
2283 | if (reqsk_queue_len(&icsk->icsk_accept_queue)) | |
1da177e4 | 2284 | goto start_req; |
463c84b9 | 2285 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
1bde5ac4 | 2286 | sk = sk_nulls_next(sk); |
1da177e4 LT |
2287 | } |
2288 | get_sk: | |
c25eb3bf | 2289 | sk_nulls_for_each_from(sk, node) { |
8475ef9f PE |
2290 | if (!net_eq(sock_net(sk), net)) |
2291 | continue; | |
2292 | if (sk->sk_family == st->family) { | |
1da177e4 LT |
2293 | cur = sk; |
2294 | goto out; | |
2295 | } | |
e905a9ed | 2296 | icsk = inet_csk(sk); |
463c84b9 ACM |
2297 | read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
2298 | if (reqsk_queue_len(&icsk->icsk_accept_queue)) { | |
1da177e4 LT |
2299 | start_req: |
2300 | st->uid = sock_i_uid(sk); | |
2301 | st->syn_wait_sk = sk; | |
2302 | st->state = TCP_SEQ_STATE_OPENREQ; | |
2303 | st->sbucket = 0; | |
2304 | goto get_req; | |
2305 | } | |
463c84b9 | 2306 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); |
1da177e4 | 2307 | } |
5caea4ea | 2308 | spin_unlock_bh(&ilb->lock); |
a8b690f9 | 2309 | st->offset = 0; |
0f7ff927 | 2310 | if (++st->bucket < INET_LHTABLE_SIZE) { |
5caea4ea ED |
2311 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
2312 | spin_lock_bh(&ilb->lock); | |
c25eb3bf | 2313 | sk = sk_nulls_head(&ilb->head); |
1da177e4 LT |
2314 | goto get_sk; |
2315 | } | |
2316 | cur = NULL; | |
2317 | out: | |
2318 | return cur; | |
2319 | } | |
2320 | ||
2321 | static void *listening_get_idx(struct seq_file *seq, loff_t *pos) | |
2322 | { | |
a8b690f9 TH |
2323 | struct tcp_iter_state *st = seq->private; |
2324 | void *rc; | |
2325 | ||
2326 | st->bucket = 0; | |
2327 | st->offset = 0; | |
2328 | rc = listening_get_next(seq, NULL); | |
1da177e4 LT |
2329 | |
2330 | while (rc && *pos) { | |
2331 | rc = listening_get_next(seq, rc); | |
2332 | --*pos; | |
2333 | } | |
2334 | return rc; | |
2335 | } | |
2336 | ||
a2a385d6 | 2337 | static inline bool empty_bucket(struct tcp_iter_state *st) |
6eac5604 | 2338 | { |
3ab5aee7 ED |
2339 | return hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].chain) && |
2340 | hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].twchain); | |
6eac5604 AK |
2341 | } |
2342 | ||
a8b690f9 TH |
2343 | /* |
2344 | * Get first established socket starting from bucket given in st->bucket. | |
2345 | * If st->bucket is zero, the very first socket in the hash is returned. | |
2346 | */ | |
1da177e4 LT |
2347 | static void *established_get_first(struct seq_file *seq) |
2348 | { | |
5799de0b | 2349 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2350 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2351 | void *rc = NULL; |
2352 | ||
a8b690f9 TH |
2353 | st->offset = 0; |
2354 | for (; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) { | |
1da177e4 | 2355 | struct sock *sk; |
3ab5aee7 | 2356 | struct hlist_nulls_node *node; |
8feaf0c0 | 2357 | struct inet_timewait_sock *tw; |
9db66bdc | 2358 | spinlock_t *lock = inet_ehash_lockp(&tcp_hashinfo, st->bucket); |
1da177e4 | 2359 | |
6eac5604 AK |
2360 | /* Lockless fast path for the common case of empty buckets */ |
2361 | if (empty_bucket(st)) | |
2362 | continue; | |
2363 | ||
9db66bdc | 2364 | spin_lock_bh(lock); |
3ab5aee7 | 2365 | sk_nulls_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) { |
f40c8174 | 2366 | if (sk->sk_family != st->family || |
878628fb | 2367 | !net_eq(sock_net(sk), net)) { |
1da177e4 LT |
2368 | continue; |
2369 | } | |
2370 | rc = sk; | |
2371 | goto out; | |
2372 | } | |
2373 | st->state = TCP_SEQ_STATE_TIME_WAIT; | |
8feaf0c0 | 2374 | inet_twsk_for_each(tw, node, |
dbca9b27 | 2375 | &tcp_hashinfo.ehash[st->bucket].twchain) { |
28518fc1 | 2376 | if (tw->tw_family != st->family || |
878628fb | 2377 | !net_eq(twsk_net(tw), net)) { |
1da177e4 LT |
2378 | continue; |
2379 | } | |
2380 | rc = tw; | |
2381 | goto out; | |
2382 | } | |
9db66bdc | 2383 | spin_unlock_bh(lock); |
1da177e4 LT |
2384 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2385 | } | |
2386 | out: | |
2387 | return rc; | |
2388 | } | |
2389 | ||
2390 | static void *established_get_next(struct seq_file *seq, void *cur) | |
2391 | { | |
2392 | struct sock *sk = cur; | |
8feaf0c0 | 2393 | struct inet_timewait_sock *tw; |
3ab5aee7 | 2394 | struct hlist_nulls_node *node; |
5799de0b | 2395 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2396 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2397 | |
2398 | ++st->num; | |
a8b690f9 | 2399 | ++st->offset; |
1da177e4 LT |
2400 | |
2401 | if (st->state == TCP_SEQ_STATE_TIME_WAIT) { | |
2402 | tw = cur; | |
2403 | tw = tw_next(tw); | |
2404 | get_tw: | |
878628fb | 2405 | while (tw && (tw->tw_family != st->family || !net_eq(twsk_net(tw), net))) { |
1da177e4 LT |
2406 | tw = tw_next(tw); |
2407 | } | |
2408 | if (tw) { | |
2409 | cur = tw; | |
2410 | goto out; | |
2411 | } | |
9db66bdc | 2412 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
1da177e4 LT |
2413 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2414 | ||
6eac5604 | 2415 | /* Look for next non empty bucket */ |
a8b690f9 | 2416 | st->offset = 0; |
f373b53b | 2417 | while (++st->bucket <= tcp_hashinfo.ehash_mask && |
6eac5604 AK |
2418 | empty_bucket(st)) |
2419 | ; | |
f373b53b | 2420 | if (st->bucket > tcp_hashinfo.ehash_mask) |
6eac5604 AK |
2421 | return NULL; |
2422 | ||
9db66bdc | 2423 | spin_lock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
3ab5aee7 | 2424 | sk = sk_nulls_head(&tcp_hashinfo.ehash[st->bucket].chain); |
1da177e4 | 2425 | } else |
3ab5aee7 | 2426 | sk = sk_nulls_next(sk); |
1da177e4 | 2427 | |
3ab5aee7 | 2428 | sk_nulls_for_each_from(sk, node) { |
878628fb | 2429 | if (sk->sk_family == st->family && net_eq(sock_net(sk), net)) |
1da177e4 LT |
2430 | goto found; |
2431 | } | |
2432 | ||
2433 | st->state = TCP_SEQ_STATE_TIME_WAIT; | |
dbca9b27 | 2434 | tw = tw_head(&tcp_hashinfo.ehash[st->bucket].twchain); |
1da177e4 LT |
2435 | goto get_tw; |
2436 | found: | |
2437 | cur = sk; | |
2438 | out: | |
2439 | return cur; | |
2440 | } | |
2441 | ||
2442 | static void *established_get_idx(struct seq_file *seq, loff_t pos) | |
2443 | { | |
a8b690f9 TH |
2444 | struct tcp_iter_state *st = seq->private; |
2445 | void *rc; | |
2446 | ||
2447 | st->bucket = 0; | |
2448 | rc = established_get_first(seq); | |
1da177e4 LT |
2449 | |
2450 | while (rc && pos) { | |
2451 | rc = established_get_next(seq, rc); | |
2452 | --pos; | |
7174259e | 2453 | } |
1da177e4 LT |
2454 | return rc; |
2455 | } | |
2456 | ||
2457 | static void *tcp_get_idx(struct seq_file *seq, loff_t pos) | |
2458 | { | |
2459 | void *rc; | |
5799de0b | 2460 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2461 | |
1da177e4 LT |
2462 | st->state = TCP_SEQ_STATE_LISTENING; |
2463 | rc = listening_get_idx(seq, &pos); | |
2464 | ||
2465 | if (!rc) { | |
1da177e4 LT |
2466 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2467 | rc = established_get_idx(seq, pos); | |
2468 | } | |
2469 | ||
2470 | return rc; | |
2471 | } | |
2472 | ||
a8b690f9 TH |
2473 | static void *tcp_seek_last_pos(struct seq_file *seq) |
2474 | { | |
2475 | struct tcp_iter_state *st = seq->private; | |
2476 | int offset = st->offset; | |
2477 | int orig_num = st->num; | |
2478 | void *rc = NULL; | |
2479 | ||
2480 | switch (st->state) { | |
2481 | case TCP_SEQ_STATE_OPENREQ: | |
2482 | case TCP_SEQ_STATE_LISTENING: | |
2483 | if (st->bucket >= INET_LHTABLE_SIZE) | |
2484 | break; | |
2485 | st->state = TCP_SEQ_STATE_LISTENING; | |
2486 | rc = listening_get_next(seq, NULL); | |
2487 | while (offset-- && rc) | |
2488 | rc = listening_get_next(seq, rc); | |
2489 | if (rc) | |
2490 | break; | |
2491 | st->bucket = 0; | |
2492 | /* Fallthrough */ | |
2493 | case TCP_SEQ_STATE_ESTABLISHED: | |
2494 | case TCP_SEQ_STATE_TIME_WAIT: | |
2495 | st->state = TCP_SEQ_STATE_ESTABLISHED; | |
2496 | if (st->bucket > tcp_hashinfo.ehash_mask) | |
2497 | break; | |
2498 | rc = established_get_first(seq); | |
2499 | while (offset-- && rc) | |
2500 | rc = established_get_next(seq, rc); | |
2501 | } | |
2502 | ||
2503 | st->num = orig_num; | |
2504 | ||
2505 | return rc; | |
2506 | } | |
2507 | ||
1da177e4 LT |
2508 | static void *tcp_seq_start(struct seq_file *seq, loff_t *pos) |
2509 | { | |
5799de0b | 2510 | struct tcp_iter_state *st = seq->private; |
a8b690f9 TH |
2511 | void *rc; |
2512 | ||
2513 | if (*pos && *pos == st->last_pos) { | |
2514 | rc = tcp_seek_last_pos(seq); | |
2515 | if (rc) | |
2516 | goto out; | |
2517 | } | |
2518 | ||
1da177e4 LT |
2519 | st->state = TCP_SEQ_STATE_LISTENING; |
2520 | st->num = 0; | |
a8b690f9 TH |
2521 | st->bucket = 0; |
2522 | st->offset = 0; | |
2523 | rc = *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
2524 | ||
2525 | out: | |
2526 | st->last_pos = *pos; | |
2527 | return rc; | |
1da177e4 LT |
2528 | } |
2529 | ||
2530 | static void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2531 | { | |
a8b690f9 | 2532 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2533 | void *rc = NULL; |
1da177e4 LT |
2534 | |
2535 | if (v == SEQ_START_TOKEN) { | |
2536 | rc = tcp_get_idx(seq, 0); | |
2537 | goto out; | |
2538 | } | |
1da177e4 LT |
2539 | |
2540 | switch (st->state) { | |
2541 | case TCP_SEQ_STATE_OPENREQ: | |
2542 | case TCP_SEQ_STATE_LISTENING: | |
2543 | rc = listening_get_next(seq, v); | |
2544 | if (!rc) { | |
1da177e4 | 2545 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
a8b690f9 TH |
2546 | st->bucket = 0; |
2547 | st->offset = 0; | |
1da177e4 LT |
2548 | rc = established_get_first(seq); |
2549 | } | |
2550 | break; | |
2551 | case TCP_SEQ_STATE_ESTABLISHED: | |
2552 | case TCP_SEQ_STATE_TIME_WAIT: | |
2553 | rc = established_get_next(seq, v); | |
2554 | break; | |
2555 | } | |
2556 | out: | |
2557 | ++*pos; | |
a8b690f9 | 2558 | st->last_pos = *pos; |
1da177e4 LT |
2559 | return rc; |
2560 | } | |
2561 | ||
2562 | static void tcp_seq_stop(struct seq_file *seq, void *v) | |
2563 | { | |
5799de0b | 2564 | struct tcp_iter_state *st = seq->private; |
1da177e4 LT |
2565 | |
2566 | switch (st->state) { | |
2567 | case TCP_SEQ_STATE_OPENREQ: | |
2568 | if (v) { | |
463c84b9 ACM |
2569 | struct inet_connection_sock *icsk = inet_csk(st->syn_wait_sk); |
2570 | read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock); | |
1da177e4 LT |
2571 | } |
2572 | case TCP_SEQ_STATE_LISTENING: | |
2573 | if (v != SEQ_START_TOKEN) | |
5caea4ea | 2574 | spin_unlock_bh(&tcp_hashinfo.listening_hash[st->bucket].lock); |
1da177e4 LT |
2575 | break; |
2576 | case TCP_SEQ_STATE_TIME_WAIT: | |
2577 | case TCP_SEQ_STATE_ESTABLISHED: | |
2578 | if (v) | |
9db66bdc | 2579 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
1da177e4 LT |
2580 | break; |
2581 | } | |
2582 | } | |
2583 | ||
73cb88ec | 2584 | int tcp_seq_open(struct inode *inode, struct file *file) |
1da177e4 LT |
2585 | { |
2586 | struct tcp_seq_afinfo *afinfo = PDE(inode)->data; | |
1da177e4 | 2587 | struct tcp_iter_state *s; |
52d6f3f1 | 2588 | int err; |
1da177e4 | 2589 | |
52d6f3f1 DL |
2590 | err = seq_open_net(inode, file, &afinfo->seq_ops, |
2591 | sizeof(struct tcp_iter_state)); | |
2592 | if (err < 0) | |
2593 | return err; | |
f40c8174 | 2594 | |
52d6f3f1 | 2595 | s = ((struct seq_file *)file->private_data)->private; |
1da177e4 | 2596 | s->family = afinfo->family; |
a8b690f9 | 2597 | s->last_pos = 0; |
f40c8174 DL |
2598 | return 0; |
2599 | } | |
73cb88ec | 2600 | EXPORT_SYMBOL(tcp_seq_open); |
f40c8174 | 2601 | |
6f8b13bc | 2602 | int tcp_proc_register(struct net *net, struct tcp_seq_afinfo *afinfo) |
1da177e4 LT |
2603 | { |
2604 | int rc = 0; | |
2605 | struct proc_dir_entry *p; | |
2606 | ||
9427c4b3 DL |
2607 | afinfo->seq_ops.start = tcp_seq_start; |
2608 | afinfo->seq_ops.next = tcp_seq_next; | |
2609 | afinfo->seq_ops.stop = tcp_seq_stop; | |
2610 | ||
84841c3c | 2611 | p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net, |
73cb88ec | 2612 | afinfo->seq_fops, afinfo); |
84841c3c | 2613 | if (!p) |
1da177e4 LT |
2614 | rc = -ENOMEM; |
2615 | return rc; | |
2616 | } | |
4bc2f18b | 2617 | EXPORT_SYMBOL(tcp_proc_register); |
1da177e4 | 2618 | |
6f8b13bc | 2619 | void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo) |
1da177e4 | 2620 | { |
6f8b13bc | 2621 | proc_net_remove(net, afinfo->name); |
1da177e4 | 2622 | } |
4bc2f18b | 2623 | EXPORT_SYMBOL(tcp_proc_unregister); |
1da177e4 | 2624 | |
cf533ea5 | 2625 | static void get_openreq4(const struct sock *sk, const struct request_sock *req, |
a7cb5a49 | 2626 | struct seq_file *f, int i, kuid_t uid, int *len) |
1da177e4 | 2627 | { |
2e6599cb | 2628 | const struct inet_request_sock *ireq = inet_rsk(req); |
a399a805 | 2629 | long delta = req->expires - jiffies; |
1da177e4 | 2630 | |
5e659e4c | 2631 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
71338aa7 | 2632 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %u %d %pK%n", |
1da177e4 | 2633 | i, |
2e6599cb | 2634 | ireq->loc_addr, |
c720c7e8 | 2635 | ntohs(inet_sk(sk)->inet_sport), |
2e6599cb ACM |
2636 | ireq->rmt_addr, |
2637 | ntohs(ireq->rmt_port), | |
1da177e4 LT |
2638 | TCP_SYN_RECV, |
2639 | 0, 0, /* could print option size, but that is af dependent. */ | |
2640 | 1, /* timers active (only the expire timer) */ | |
a399a805 | 2641 | jiffies_delta_to_clock_t(delta), |
1da177e4 | 2642 | req->retrans, |
a7cb5a49 | 2643 | from_kuid_munged(seq_user_ns(f), uid), |
1da177e4 LT |
2644 | 0, /* non standard timer */ |
2645 | 0, /* open_requests have no inode */ | |
2646 | atomic_read(&sk->sk_refcnt), | |
5e659e4c PE |
2647 | req, |
2648 | len); | |
1da177e4 LT |
2649 | } |
2650 | ||
5e659e4c | 2651 | static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i, int *len) |
1da177e4 LT |
2652 | { |
2653 | int timer_active; | |
2654 | unsigned long timer_expires; | |
cf533ea5 | 2655 | const struct tcp_sock *tp = tcp_sk(sk); |
cf4c6bf8 | 2656 | const struct inet_connection_sock *icsk = inet_csk(sk); |
cf533ea5 | 2657 | const struct inet_sock *inet = inet_sk(sk); |
168a8f58 | 2658 | struct fastopen_queue *fastopenq = icsk->icsk_accept_queue.fastopenq; |
c720c7e8 ED |
2659 | __be32 dest = inet->inet_daddr; |
2660 | __be32 src = inet->inet_rcv_saddr; | |
2661 | __u16 destp = ntohs(inet->inet_dport); | |
2662 | __u16 srcp = ntohs(inet->inet_sport); | |
49d09007 | 2663 | int rx_queue; |
1da177e4 | 2664 | |
463c84b9 | 2665 | if (icsk->icsk_pending == ICSK_TIME_RETRANS) { |
1da177e4 | 2666 | timer_active = 1; |
463c84b9 ACM |
2667 | timer_expires = icsk->icsk_timeout; |
2668 | } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { | |
1da177e4 | 2669 | timer_active = 4; |
463c84b9 | 2670 | timer_expires = icsk->icsk_timeout; |
cf4c6bf8 | 2671 | } else if (timer_pending(&sk->sk_timer)) { |
1da177e4 | 2672 | timer_active = 2; |
cf4c6bf8 | 2673 | timer_expires = sk->sk_timer.expires; |
1da177e4 LT |
2674 | } else { |
2675 | timer_active = 0; | |
2676 | timer_expires = jiffies; | |
2677 | } | |
2678 | ||
49d09007 ED |
2679 | if (sk->sk_state == TCP_LISTEN) |
2680 | rx_queue = sk->sk_ack_backlog; | |
2681 | else | |
2682 | /* | |
2683 | * because we dont lock socket, we might find a transient negative value | |
2684 | */ | |
2685 | rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0); | |
2686 | ||
5e659e4c | 2687 | seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " |
71338aa7 | 2688 | "%08X %5d %8d %lu %d %pK %lu %lu %u %u %d%n", |
cf4c6bf8 | 2689 | i, src, srcp, dest, destp, sk->sk_state, |
47da8ee6 | 2690 | tp->write_seq - tp->snd_una, |
49d09007 | 2691 | rx_queue, |
1da177e4 | 2692 | timer_active, |
a399a805 | 2693 | jiffies_delta_to_clock_t(timer_expires - jiffies), |
463c84b9 | 2694 | icsk->icsk_retransmits, |
a7cb5a49 | 2695 | from_kuid_munged(seq_user_ns(f), sock_i_uid(sk)), |
6687e988 | 2696 | icsk->icsk_probes_out, |
cf4c6bf8 IJ |
2697 | sock_i_ino(sk), |
2698 | atomic_read(&sk->sk_refcnt), sk, | |
7be87351 SH |
2699 | jiffies_to_clock_t(icsk->icsk_rto), |
2700 | jiffies_to_clock_t(icsk->icsk_ack.ato), | |
463c84b9 | 2701 | (icsk->icsk_ack.quick << 1) | icsk->icsk_ack.pingpong, |
1da177e4 | 2702 | tp->snd_cwnd, |
168a8f58 JC |
2703 | sk->sk_state == TCP_LISTEN ? |
2704 | (fastopenq ? fastopenq->max_qlen : 0) : | |
2705 | (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh), | |
5e659e4c | 2706 | len); |
1da177e4 LT |
2707 | } |
2708 | ||
cf533ea5 | 2709 | static void get_timewait4_sock(const struct inet_timewait_sock *tw, |
5e659e4c | 2710 | struct seq_file *f, int i, int *len) |
1da177e4 | 2711 | { |
23f33c2d | 2712 | __be32 dest, src; |
1da177e4 | 2713 | __u16 destp, srcp; |
a399a805 | 2714 | long delta = tw->tw_ttd - jiffies; |
1da177e4 LT |
2715 | |
2716 | dest = tw->tw_daddr; | |
2717 | src = tw->tw_rcv_saddr; | |
2718 | destp = ntohs(tw->tw_dport); | |
2719 | srcp = ntohs(tw->tw_sport); | |
2720 | ||
5e659e4c | 2721 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
71338aa7 | 2722 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK%n", |
1da177e4 | 2723 | i, src, srcp, dest, destp, tw->tw_substate, 0, 0, |
a399a805 | 2724 | 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, |
5e659e4c | 2725 | atomic_read(&tw->tw_refcnt), tw, len); |
1da177e4 LT |
2726 | } |
2727 | ||
2728 | #define TMPSZ 150 | |
2729 | ||
2730 | static int tcp4_seq_show(struct seq_file *seq, void *v) | |
2731 | { | |
5799de0b | 2732 | struct tcp_iter_state *st; |
5e659e4c | 2733 | int len; |
1da177e4 LT |
2734 | |
2735 | if (v == SEQ_START_TOKEN) { | |
2736 | seq_printf(seq, "%-*s\n", TMPSZ - 1, | |
2737 | " sl local_address rem_address st tx_queue " | |
2738 | "rx_queue tr tm->when retrnsmt uid timeout " | |
2739 | "inode"); | |
2740 | goto out; | |
2741 | } | |
2742 | st = seq->private; | |
2743 | ||
2744 | switch (st->state) { | |
2745 | case TCP_SEQ_STATE_LISTENING: | |
2746 | case TCP_SEQ_STATE_ESTABLISHED: | |
5e659e4c | 2747 | get_tcp4_sock(v, seq, st->num, &len); |
1da177e4 LT |
2748 | break; |
2749 | case TCP_SEQ_STATE_OPENREQ: | |
5e659e4c | 2750 | get_openreq4(st->syn_wait_sk, v, seq, st->num, st->uid, &len); |
1da177e4 LT |
2751 | break; |
2752 | case TCP_SEQ_STATE_TIME_WAIT: | |
5e659e4c | 2753 | get_timewait4_sock(v, seq, st->num, &len); |
1da177e4 LT |
2754 | break; |
2755 | } | |
5e659e4c | 2756 | seq_printf(seq, "%*s\n", TMPSZ - 1 - len, ""); |
1da177e4 LT |
2757 | out: |
2758 | return 0; | |
2759 | } | |
2760 | ||
73cb88ec AV |
2761 | static const struct file_operations tcp_afinfo_seq_fops = { |
2762 | .owner = THIS_MODULE, | |
2763 | .open = tcp_seq_open, | |
2764 | .read = seq_read, | |
2765 | .llseek = seq_lseek, | |
2766 | .release = seq_release_net | |
2767 | }; | |
2768 | ||
1da177e4 | 2769 | static struct tcp_seq_afinfo tcp4_seq_afinfo = { |
1da177e4 LT |
2770 | .name = "tcp", |
2771 | .family = AF_INET, | |
73cb88ec | 2772 | .seq_fops = &tcp_afinfo_seq_fops, |
9427c4b3 DL |
2773 | .seq_ops = { |
2774 | .show = tcp4_seq_show, | |
2775 | }, | |
1da177e4 LT |
2776 | }; |
2777 | ||
2c8c1e72 | 2778 | static int __net_init tcp4_proc_init_net(struct net *net) |
757764f6 PE |
2779 | { |
2780 | return tcp_proc_register(net, &tcp4_seq_afinfo); | |
2781 | } | |
2782 | ||
2c8c1e72 | 2783 | static void __net_exit tcp4_proc_exit_net(struct net *net) |
757764f6 PE |
2784 | { |
2785 | tcp_proc_unregister(net, &tcp4_seq_afinfo); | |
2786 | } | |
2787 | ||
2788 | static struct pernet_operations tcp4_net_ops = { | |
2789 | .init = tcp4_proc_init_net, | |
2790 | .exit = tcp4_proc_exit_net, | |
2791 | }; | |
2792 | ||
1da177e4 LT |
2793 | int __init tcp4_proc_init(void) |
2794 | { | |
757764f6 | 2795 | return register_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2796 | } |
2797 | ||
2798 | void tcp4_proc_exit(void) | |
2799 | { | |
757764f6 | 2800 | unregister_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2801 | } |
2802 | #endif /* CONFIG_PROC_FS */ | |
2803 | ||
bf296b12 HX |
2804 | struct sk_buff **tcp4_gro_receive(struct sk_buff **head, struct sk_buff *skb) |
2805 | { | |
b71d1d42 | 2806 | const struct iphdr *iph = skb_gro_network_header(skb); |
861b6501 ED |
2807 | __wsum wsum; |
2808 | __sum16 sum; | |
bf296b12 HX |
2809 | |
2810 | switch (skb->ip_summed) { | |
2811 | case CHECKSUM_COMPLETE: | |
86911732 | 2812 | if (!tcp_v4_check(skb_gro_len(skb), iph->saddr, iph->daddr, |
bf296b12 HX |
2813 | skb->csum)) { |
2814 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
2815 | break; | |
2816 | } | |
861b6501 | 2817 | flush: |
bf296b12 HX |
2818 | NAPI_GRO_CB(skb)->flush = 1; |
2819 | return NULL; | |
861b6501 ED |
2820 | |
2821 | case CHECKSUM_NONE: | |
2822 | wsum = csum_tcpudp_nofold(iph->saddr, iph->daddr, | |
2823 | skb_gro_len(skb), IPPROTO_TCP, 0); | |
2824 | sum = csum_fold(skb_checksum(skb, | |
2825 | skb_gro_offset(skb), | |
2826 | skb_gro_len(skb), | |
2827 | wsum)); | |
2828 | if (sum) | |
2829 | goto flush; | |
2830 | ||
2831 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
2832 | break; | |
bf296b12 HX |
2833 | } |
2834 | ||
2835 | return tcp_gro_receive(head, skb); | |
2836 | } | |
bf296b12 HX |
2837 | |
2838 | int tcp4_gro_complete(struct sk_buff *skb) | |
2839 | { | |
b71d1d42 | 2840 | const struct iphdr *iph = ip_hdr(skb); |
bf296b12 HX |
2841 | struct tcphdr *th = tcp_hdr(skb); |
2842 | ||
2843 | th->check = ~tcp_v4_check(skb->len - skb_transport_offset(skb), | |
2844 | iph->saddr, iph->daddr, 0); | |
2845 | skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; | |
2846 | ||
2847 | return tcp_gro_complete(skb); | |
2848 | } | |
bf296b12 | 2849 | |
1da177e4 LT |
2850 | struct proto tcp_prot = { |
2851 | .name = "TCP", | |
2852 | .owner = THIS_MODULE, | |
2853 | .close = tcp_close, | |
2854 | .connect = tcp_v4_connect, | |
2855 | .disconnect = tcp_disconnect, | |
463c84b9 | 2856 | .accept = inet_csk_accept, |
1da177e4 LT |
2857 | .ioctl = tcp_ioctl, |
2858 | .init = tcp_v4_init_sock, | |
2859 | .destroy = tcp_v4_destroy_sock, | |
2860 | .shutdown = tcp_shutdown, | |
2861 | .setsockopt = tcp_setsockopt, | |
2862 | .getsockopt = tcp_getsockopt, | |
1da177e4 | 2863 | .recvmsg = tcp_recvmsg, |
7ba42910 CG |
2864 | .sendmsg = tcp_sendmsg, |
2865 | .sendpage = tcp_sendpage, | |
1da177e4 | 2866 | .backlog_rcv = tcp_v4_do_rcv, |
46d3ceab | 2867 | .release_cb = tcp_release_cb, |
563d34d0 | 2868 | .mtu_reduced = tcp_v4_mtu_reduced, |
ab1e0a13 ACM |
2869 | .hash = inet_hash, |
2870 | .unhash = inet_unhash, | |
2871 | .get_port = inet_csk_get_port, | |
1da177e4 LT |
2872 | .enter_memory_pressure = tcp_enter_memory_pressure, |
2873 | .sockets_allocated = &tcp_sockets_allocated, | |
0a5578cf | 2874 | .orphan_count = &tcp_orphan_count, |
1da177e4 LT |
2875 | .memory_allocated = &tcp_memory_allocated, |
2876 | .memory_pressure = &tcp_memory_pressure, | |
1da177e4 LT |
2877 | .sysctl_wmem = sysctl_tcp_wmem, |
2878 | .sysctl_rmem = sysctl_tcp_rmem, | |
2879 | .max_header = MAX_TCP_HEADER, | |
2880 | .obj_size = sizeof(struct tcp_sock), | |
3ab5aee7 | 2881 | .slab_flags = SLAB_DESTROY_BY_RCU, |
6d6ee43e | 2882 | .twsk_prot = &tcp_timewait_sock_ops, |
60236fdd | 2883 | .rsk_prot = &tcp_request_sock_ops, |
39d8cda7 | 2884 | .h.hashinfo = &tcp_hashinfo, |
7ba42910 | 2885 | .no_autobind = true, |
543d9cfe ACM |
2886 | #ifdef CONFIG_COMPAT |
2887 | .compat_setsockopt = compat_tcp_setsockopt, | |
2888 | .compat_getsockopt = compat_tcp_getsockopt, | |
2889 | #endif | |
c255a458 | 2890 | #ifdef CONFIG_MEMCG_KMEM |
d1a4c0b3 GC |
2891 | .init_cgroup = tcp_init_cgroup, |
2892 | .destroy_cgroup = tcp_destroy_cgroup, | |
2893 | .proto_cgroup = tcp_proto_cgroup, | |
2894 | #endif | |
1da177e4 | 2895 | }; |
4bc2f18b | 2896 | EXPORT_SYMBOL(tcp_prot); |
1da177e4 | 2897 | |
046ee902 DL |
2898 | static int __net_init tcp_sk_init(struct net *net) |
2899 | { | |
be9f4a44 | 2900 | return 0; |
046ee902 DL |
2901 | } |
2902 | ||
2903 | static void __net_exit tcp_sk_exit(struct net *net) | |
2904 | { | |
b099ce26 EB |
2905 | } |
2906 | ||
2907 | static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list) | |
2908 | { | |
2909 | inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET); | |
046ee902 DL |
2910 | } |
2911 | ||
2912 | static struct pernet_operations __net_initdata tcp_sk_ops = { | |
b099ce26 EB |
2913 | .init = tcp_sk_init, |
2914 | .exit = tcp_sk_exit, | |
2915 | .exit_batch = tcp_sk_exit_batch, | |
046ee902 DL |
2916 | }; |
2917 | ||
9b0f976f | 2918 | void __init tcp_v4_init(void) |
1da177e4 | 2919 | { |
5caea4ea | 2920 | inet_hashinfo_init(&tcp_hashinfo); |
6a1b3054 | 2921 | if (register_pernet_subsys(&tcp_sk_ops)) |
1da177e4 | 2922 | panic("Failed to create the TCP control socket.\n"); |
1da177e4 | 2923 | } |