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2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
4 | * operating system. INET is implemented using the BSD Socket | |
5 | * interface as the means of communication with the user level. | |
6 | * | |
7 | * Implementation of the Transmission Control Protocol(TCP). | |
8 | * | |
1da177e4 LT |
9 | * IPv4 specific functions |
10 | * | |
1da177e4 LT |
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 | |
1da177e4 LT |
17 | */ |
18 | ||
19 | /* | |
20 | * Changes: | |
21 | * David S. Miller : New socket lookup architecture. | |
22 | * This code is dedicated to John Dyson. | |
23 | * David S. Miller : Change semantics of established hash, | |
24 | * half is devoted to TIME_WAIT sockets | |
25 | * and the rest go in the other half. | |
26 | * Andi Kleen : Add support for syncookies and fixed | |
27 | * some bugs: ip options weren't passed to | |
28 | * the TCP layer, missed a check for an | |
29 | * ACK bit. | |
30 | * Andi Kleen : Implemented fast path mtu discovery. | |
31 | * Fixed many serious bugs in the | |
60236fdd | 32 | * request_sock handling and moved |
1da177e4 LT |
33 | * most of it into the af independent code. |
34 | * Added tail drop and some other bugfixes. | |
caa20d9a | 35 | * Added new listen semantics. |
1da177e4 LT |
36 | * Mike McLagan : Routing by source |
37 | * Juan Jose Ciarlante: ip_dynaddr bits | |
38 | * Andi Kleen: various fixes. | |
39 | * Vitaly E. Lavrov : Transparent proxy revived after year | |
40 | * coma. | |
41 | * Andi Kleen : Fix new listen. | |
42 | * Andi Kleen : Fix accept error reporting. | |
43 | * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which | |
44 | * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind | |
45 | * a single port at the same time. | |
46 | */ | |
47 | ||
afd46503 | 48 | #define pr_fmt(fmt) "TCP: " fmt |
1da177e4 | 49 | |
eb4dea58 | 50 | #include <linux/bottom_half.h> |
1da177e4 LT |
51 | #include <linux/types.h> |
52 | #include <linux/fcntl.h> | |
53 | #include <linux/module.h> | |
54 | #include <linux/random.h> | |
55 | #include <linux/cache.h> | |
56 | #include <linux/jhash.h> | |
57 | #include <linux/init.h> | |
58 | #include <linux/times.h> | |
5a0e3ad6 | 59 | #include <linux/slab.h> |
1da177e4 | 60 | |
457c4cbc | 61 | #include <net/net_namespace.h> |
1da177e4 | 62 | #include <net/icmp.h> |
304a1618 | 63 | #include <net/inet_hashtables.h> |
1da177e4 | 64 | #include <net/tcp.h> |
20380731 | 65 | #include <net/transp_v6.h> |
1da177e4 LT |
66 | #include <net/ipv6.h> |
67 | #include <net/inet_common.h> | |
6d6ee43e | 68 | #include <net/timewait_sock.h> |
1da177e4 | 69 | #include <net/xfrm.h> |
6e5714ea | 70 | #include <net/secure_seq.h> |
076bb0c8 | 71 | #include <net/busy_poll.h> |
1da177e4 LT |
72 | |
73 | #include <linux/inet.h> | |
74 | #include <linux/ipv6.h> | |
75 | #include <linux/stddef.h> | |
76 | #include <linux/proc_fs.h> | |
77 | #include <linux/seq_file.h> | |
6797318e | 78 | #include <linux/inetdevice.h> |
1da177e4 | 79 | |
cf80e0e4 | 80 | #include <crypto/hash.h> |
cfb6eeb4 YH |
81 | #include <linux/scatterlist.h> |
82 | ||
c24b14c4 SL |
83 | #include <trace/events/tcp.h> |
84 | ||
cfb6eeb4 | 85 | #ifdef CONFIG_TCP_MD5SIG |
a915da9b | 86 | static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, |
318cf7aa | 87 | __be32 daddr, __be32 saddr, const struct tcphdr *th); |
cfb6eeb4 YH |
88 | #endif |
89 | ||
5caea4ea | 90 | struct inet_hashinfo tcp_hashinfo; |
4bc2f18b | 91 | EXPORT_SYMBOL(tcp_hashinfo); |
1da177e4 | 92 | |
84b114b9 | 93 | static u32 tcp_v4_init_seq(const struct sk_buff *skb) |
1da177e4 | 94 | { |
84b114b9 ED |
95 | return secure_tcp_seq(ip_hdr(skb)->daddr, |
96 | ip_hdr(skb)->saddr, | |
97 | tcp_hdr(skb)->dest, | |
98 | tcp_hdr(skb)->source); | |
99 | } | |
100 | ||
5d2ed052 | 101 | static u32 tcp_v4_init_ts_off(const struct net *net, const struct sk_buff *skb) |
84b114b9 | 102 | { |
5d2ed052 | 103 | return secure_tcp_ts_off(net, ip_hdr(skb)->daddr, ip_hdr(skb)->saddr); |
1da177e4 LT |
104 | } |
105 | ||
6d6ee43e ACM |
106 | int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp) |
107 | { | |
79e9fed4 | 108 | const struct inet_timewait_sock *tw = inet_twsk(sktw); |
6d6ee43e ACM |
109 | const struct tcp_timewait_sock *tcptw = tcp_twsk(sktw); |
110 | struct tcp_sock *tp = tcp_sk(sk); | |
79e9fed4 MŻ |
111 | int reuse = sock_net(sk)->ipv4.sysctl_tcp_tw_reuse; |
112 | ||
113 | if (reuse == 2) { | |
114 | /* Still does not detect *everything* that goes through | |
115 | * lo, since we require a loopback src or dst address | |
116 | * or direct binding to 'lo' interface. | |
117 | */ | |
118 | bool loopback = false; | |
119 | if (tw->tw_bound_dev_if == LOOPBACK_IFINDEX) | |
120 | loopback = true; | |
121 | #if IS_ENABLED(CONFIG_IPV6) | |
122 | if (tw->tw_family == AF_INET6) { | |
123 | if (ipv6_addr_loopback(&tw->tw_v6_daddr) || | |
be2644aa | 124 | ipv6_addr_v4mapped_loopback(&tw->tw_v6_daddr) || |
79e9fed4 | 125 | ipv6_addr_loopback(&tw->tw_v6_rcv_saddr) || |
be2644aa | 126 | ipv6_addr_v4mapped_loopback(&tw->tw_v6_rcv_saddr)) |
79e9fed4 MŻ |
127 | loopback = true; |
128 | } else | |
129 | #endif | |
130 | { | |
131 | if (ipv4_is_loopback(tw->tw_daddr) || | |
132 | ipv4_is_loopback(tw->tw_rcv_saddr)) | |
133 | loopback = true; | |
134 | } | |
135 | if (!loopback) | |
136 | reuse = 0; | |
137 | } | |
6d6ee43e ACM |
138 | |
139 | /* With PAWS, it is safe from the viewpoint | |
140 | of data integrity. Even without PAWS it is safe provided sequence | |
141 | spaces do not overlap i.e. at data rates <= 80Mbit/sec. | |
142 | ||
143 | Actually, the idea is close to VJ's one, only timestamp cache is | |
144 | held not per host, but per port pair and TW bucket is used as state | |
145 | holder. | |
146 | ||
147 | If TW bucket has been already destroyed we fall back to VJ's scheme | |
148 | and use initial timestamp retrieved from peer table. | |
149 | */ | |
150 | if (tcptw->tw_ts_recent_stamp && | |
cca9bab1 AB |
151 | (!twp || (reuse && time_after32(ktime_get_seconds(), |
152 | tcptw->tw_ts_recent_stamp)))) { | |
21684dc4 SB |
153 | /* In case of repair and re-using TIME-WAIT sockets we still |
154 | * want to be sure that it is safe as above but honor the | |
155 | * sequence numbers and time stamps set as part of the repair | |
156 | * process. | |
157 | * | |
158 | * Without this check re-using a TIME-WAIT socket with TCP | |
159 | * repair would accumulate a -1 on the repair assigned | |
160 | * sequence number. The first time it is reused the sequence | |
161 | * is -1, the second time -2, etc. This fixes that issue | |
162 | * without appearing to create any others. | |
163 | */ | |
164 | if (likely(!tp->repair)) { | |
0f317464 ED |
165 | u32 seq = tcptw->tw_snd_nxt + 65535 + 2; |
166 | ||
167 | if (!seq) | |
168 | seq = 1; | |
169 | WRITE_ONCE(tp->write_seq, seq); | |
21684dc4 SB |
170 | tp->rx_opt.ts_recent = tcptw->tw_ts_recent; |
171 | tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; | |
172 | } | |
6d6ee43e ACM |
173 | sock_hold(sktw); |
174 | return 1; | |
175 | } | |
176 | ||
177 | return 0; | |
178 | } | |
6d6ee43e ACM |
179 | EXPORT_SYMBOL_GPL(tcp_twsk_unique); |
180 | ||
d74bad4e AI |
181 | static int tcp_v4_pre_connect(struct sock *sk, struct sockaddr *uaddr, |
182 | int addr_len) | |
183 | { | |
184 | /* This check is replicated from tcp_v4_connect() and intended to | |
185 | * prevent BPF program called below from accessing bytes that are out | |
186 | * of the bound specified by user in addr_len. | |
187 | */ | |
188 | if (addr_len < sizeof(struct sockaddr_in)) | |
189 | return -EINVAL; | |
190 | ||
191 | sock_owned_by_me(sk); | |
192 | ||
193 | return BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr); | |
194 | } | |
195 | ||
1da177e4 LT |
196 | /* This will initiate an outgoing connection. */ |
197 | int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) | |
198 | { | |
2d7192d6 | 199 | struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
1da177e4 LT |
200 | struct inet_sock *inet = inet_sk(sk); |
201 | struct tcp_sock *tp = tcp_sk(sk); | |
dca8b089 | 202 | __be16 orig_sport, orig_dport; |
bada8adc | 203 | __be32 daddr, nexthop; |
da905bd1 | 204 | struct flowi4 *fl4; |
2d7192d6 | 205 | struct rtable *rt; |
1da177e4 | 206 | int err; |
f6d8bd05 | 207 | struct ip_options_rcu *inet_opt; |
1946e672 | 208 | struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row; |
1da177e4 LT |
209 | |
210 | if (addr_len < sizeof(struct sockaddr_in)) | |
211 | return -EINVAL; | |
212 | ||
213 | if (usin->sin_family != AF_INET) | |
214 | return -EAFNOSUPPORT; | |
215 | ||
216 | nexthop = daddr = usin->sin_addr.s_addr; | |
f6d8bd05 | 217 | inet_opt = rcu_dereference_protected(inet->inet_opt, |
1e1d04e6 | 218 | lockdep_sock_is_held(sk)); |
f6d8bd05 | 219 | if (inet_opt && inet_opt->opt.srr) { |
1da177e4 LT |
220 | if (!daddr) |
221 | return -EINVAL; | |
f6d8bd05 | 222 | nexthop = inet_opt->opt.faddr; |
1da177e4 LT |
223 | } |
224 | ||
dca8b089 DM |
225 | orig_sport = inet->inet_sport; |
226 | orig_dport = usin->sin_port; | |
da905bd1 DM |
227 | fl4 = &inet->cork.fl.u.ip4; |
228 | rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, | |
b23dd4fe DM |
229 | RT_CONN_FLAGS(sk), sk->sk_bound_dev_if, |
230 | IPPROTO_TCP, | |
0e0d44ab | 231 | orig_sport, orig_dport, sk); |
b23dd4fe DM |
232 | if (IS_ERR(rt)) { |
233 | err = PTR_ERR(rt); | |
234 | if (err == -ENETUNREACH) | |
f1d8cba6 | 235 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); |
b23dd4fe | 236 | return err; |
584bdf8c | 237 | } |
1da177e4 LT |
238 | |
239 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { | |
240 | ip_rt_put(rt); | |
241 | return -ENETUNREACH; | |
242 | } | |
243 | ||
f6d8bd05 | 244 | if (!inet_opt || !inet_opt->opt.srr) |
da905bd1 | 245 | daddr = fl4->daddr; |
1da177e4 | 246 | |
c720c7e8 | 247 | if (!inet->inet_saddr) |
da905bd1 | 248 | inet->inet_saddr = fl4->saddr; |
d1e559d0 | 249 | sk_rcv_saddr_set(sk, inet->inet_saddr); |
1da177e4 | 250 | |
c720c7e8 | 251 | if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) { |
1da177e4 LT |
252 | /* Reset inherited state */ |
253 | tp->rx_opt.ts_recent = 0; | |
254 | tp->rx_opt.ts_recent_stamp = 0; | |
ee995283 | 255 | if (likely(!tp->repair)) |
0f317464 | 256 | WRITE_ONCE(tp->write_seq, 0); |
1da177e4 LT |
257 | } |
258 | ||
c720c7e8 | 259 | inet->inet_dport = usin->sin_port; |
d1e559d0 | 260 | sk_daddr_set(sk, daddr); |
1da177e4 | 261 | |
d83d8461 | 262 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
263 | if (inet_opt) |
264 | inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
1da177e4 | 265 | |
bee7ca9e | 266 | tp->rx_opt.mss_clamp = TCP_MSS_DEFAULT; |
1da177e4 LT |
267 | |
268 | /* Socket identity is still unknown (sport may be zero). | |
269 | * However we set state to SYN-SENT and not releasing socket | |
270 | * lock select source port, enter ourselves into the hash tables and | |
271 | * complete initialization after this. | |
272 | */ | |
273 | tcp_set_state(sk, TCP_SYN_SENT); | |
1946e672 | 274 | err = inet_hash_connect(tcp_death_row, sk); |
1da177e4 LT |
275 | if (err) |
276 | goto failure; | |
277 | ||
877d1f62 | 278 | sk_set_txhash(sk); |
9e7ceb06 | 279 | |
da905bd1 | 280 | rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, |
b23dd4fe DM |
281 | inet->inet_sport, inet->inet_dport, sk); |
282 | if (IS_ERR(rt)) { | |
283 | err = PTR_ERR(rt); | |
284 | rt = NULL; | |
1da177e4 | 285 | goto failure; |
b23dd4fe | 286 | } |
1da177e4 | 287 | /* OK, now commit destination to socket. */ |
bcd76111 | 288 | sk->sk_gso_type = SKB_GSO_TCPV4; |
d8d1f30b | 289 | sk_setup_caps(sk, &rt->dst); |
19f6d3f3 | 290 | rt = NULL; |
1da177e4 | 291 | |
00355fa5 | 292 | if (likely(!tp->repair)) { |
00355fa5 | 293 | if (!tp->write_seq) |
0f317464 ED |
294 | WRITE_ONCE(tp->write_seq, |
295 | secure_tcp_seq(inet->inet_saddr, | |
296 | inet->inet_daddr, | |
297 | inet->inet_sport, | |
298 | usin->sin_port)); | |
5d2ed052 ED |
299 | tp->tsoffset = secure_tcp_ts_off(sock_net(sk), |
300 | inet->inet_saddr, | |
84b114b9 | 301 | inet->inet_daddr); |
00355fa5 | 302 | } |
1da177e4 | 303 | |
a904a069 | 304 | inet->inet_id = prandom_u32(); |
1da177e4 | 305 | |
19f6d3f3 WW |
306 | if (tcp_fastopen_defer_connect(sk, &err)) |
307 | return err; | |
308 | if (err) | |
309 | goto failure; | |
310 | ||
2b916477 | 311 | err = tcp_connect(sk); |
ee995283 | 312 | |
1da177e4 LT |
313 | if (err) |
314 | goto failure; | |
315 | ||
316 | return 0; | |
317 | ||
318 | failure: | |
7174259e ACM |
319 | /* |
320 | * This unhashes the socket and releases the local port, | |
321 | * if necessary. | |
322 | */ | |
1da177e4 LT |
323 | tcp_set_state(sk, TCP_CLOSE); |
324 | ip_rt_put(rt); | |
325 | sk->sk_route_caps = 0; | |
c720c7e8 | 326 | inet->inet_dport = 0; |
1da177e4 LT |
327 | return err; |
328 | } | |
4bc2f18b | 329 | EXPORT_SYMBOL(tcp_v4_connect); |
1da177e4 | 330 | |
1da177e4 | 331 | /* |
563d34d0 ED |
332 | * This routine reacts to ICMP_FRAG_NEEDED mtu indications as defined in RFC1191. |
333 | * It can be called through tcp_release_cb() if socket was owned by user | |
334 | * at the time tcp_v4_err() was called to handle ICMP message. | |
1da177e4 | 335 | */ |
4fab9071 | 336 | void tcp_v4_mtu_reduced(struct sock *sk) |
1da177e4 | 337 | { |
1da177e4 | 338 | struct inet_sock *inet = inet_sk(sk); |
02b2faaf ED |
339 | struct dst_entry *dst; |
340 | u32 mtu; | |
1da177e4 | 341 | |
02b2faaf ED |
342 | if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) |
343 | return; | |
344 | mtu = tcp_sk(sk)->mtu_info; | |
80d0a69f DM |
345 | dst = inet_csk_update_pmtu(sk, mtu); |
346 | if (!dst) | |
1da177e4 LT |
347 | return; |
348 | ||
1da177e4 LT |
349 | /* Something is about to be wrong... Remember soft error |
350 | * for the case, if this connection will not able to recover. | |
351 | */ | |
352 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) | |
353 | sk->sk_err_soft = EMSGSIZE; | |
354 | ||
355 | mtu = dst_mtu(dst); | |
356 | ||
357 | if (inet->pmtudisc != IP_PMTUDISC_DONT && | |
482fc609 | 358 | ip_sk_accept_pmtu(sk) && |
d83d8461 | 359 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
1da177e4 LT |
360 | tcp_sync_mss(sk, mtu); |
361 | ||
362 | /* Resend the TCP packet because it's | |
363 | * clear that the old packet has been | |
364 | * dropped. This is the new "fast" path mtu | |
365 | * discovery. | |
366 | */ | |
367 | tcp_simple_retransmit(sk); | |
368 | } /* else let the usual retransmit timer handle it */ | |
369 | } | |
4fab9071 | 370 | EXPORT_SYMBOL(tcp_v4_mtu_reduced); |
1da177e4 | 371 | |
55be7a9c DM |
372 | static void do_redirect(struct sk_buff *skb, struct sock *sk) |
373 | { | |
374 | struct dst_entry *dst = __sk_dst_check(sk, 0); | |
375 | ||
1ed5c48f | 376 | if (dst) |
6700c270 | 377 | dst->ops->redirect(dst, sk, skb); |
55be7a9c DM |
378 | } |
379 | ||
26e37360 ED |
380 | |
381 | /* handle ICMP messages on TCP_NEW_SYN_RECV request sockets */ | |
9cf74903 | 382 | void tcp_req_err(struct sock *sk, u32 seq, bool abort) |
26e37360 ED |
383 | { |
384 | struct request_sock *req = inet_reqsk(sk); | |
385 | struct net *net = sock_net(sk); | |
386 | ||
387 | /* ICMPs are not backlogged, hence we cannot get | |
388 | * an established socket here. | |
389 | */ | |
26e37360 | 390 | if (seq != tcp_rsk(req)->snt_isn) { |
02a1d6e7 | 391 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
9cf74903 | 392 | } else if (abort) { |
26e37360 ED |
393 | /* |
394 | * Still in SYN_RECV, just remove it silently. | |
395 | * There is no good way to pass the error to the newly | |
396 | * created socket, and POSIX does not want network | |
397 | * errors returned from accept(). | |
398 | */ | |
c6973669 | 399 | inet_csk_reqsk_queue_drop(req->rsk_listener, req); |
9caad864 | 400 | tcp_listendrop(req->rsk_listener); |
26e37360 | 401 | } |
ef84d8ce | 402 | reqsk_put(req); |
26e37360 ED |
403 | } |
404 | EXPORT_SYMBOL(tcp_req_err); | |
405 | ||
1da177e4 LT |
406 | /* |
407 | * This routine is called by the ICMP module when it gets some | |
408 | * sort of error condition. If err < 0 then the socket should | |
409 | * be closed and the error returned to the user. If err > 0 | |
410 | * it's just the icmp type << 8 | icmp code. After adjustment | |
411 | * header points to the first 8 bytes of the tcp header. We need | |
412 | * to find the appropriate port. | |
413 | * | |
414 | * The locking strategy used here is very "optimistic". When | |
415 | * someone else accesses the socket the ICMP is just dropped | |
416 | * and for some paths there is no check at all. | |
417 | * A more general error queue to queue errors for later handling | |
418 | * is probably better. | |
419 | * | |
420 | */ | |
421 | ||
32bbd879 | 422 | int tcp_v4_err(struct sk_buff *icmp_skb, u32 info) |
1da177e4 | 423 | { |
b71d1d42 | 424 | const struct iphdr *iph = (const struct iphdr *)icmp_skb->data; |
4d1a2d9e | 425 | struct tcphdr *th = (struct tcphdr *)(icmp_skb->data + (iph->ihl << 2)); |
f1ecd5d9 | 426 | struct inet_connection_sock *icsk; |
1da177e4 LT |
427 | struct tcp_sock *tp; |
428 | struct inet_sock *inet; | |
4d1a2d9e DL |
429 | const int type = icmp_hdr(icmp_skb)->type; |
430 | const int code = icmp_hdr(icmp_skb)->code; | |
1da177e4 | 431 | struct sock *sk; |
f1ecd5d9 | 432 | struct sk_buff *skb; |
0a672f74 | 433 | struct request_sock *fastopen; |
9a568de4 ED |
434 | u32 seq, snd_una; |
435 | s32 remaining; | |
436 | u32 delta_us; | |
1da177e4 | 437 | int err; |
4d1a2d9e | 438 | struct net *net = dev_net(icmp_skb->dev); |
1da177e4 | 439 | |
26e37360 ED |
440 | sk = __inet_lookup_established(net, &tcp_hashinfo, iph->daddr, |
441 | th->dest, iph->saddr, ntohs(th->source), | |
3fa6f616 | 442 | inet_iif(icmp_skb), 0); |
1da177e4 | 443 | if (!sk) { |
5d3848bc | 444 | __ICMP_INC_STATS(net, ICMP_MIB_INERRORS); |
32bbd879 | 445 | return -ENOENT; |
1da177e4 LT |
446 | } |
447 | if (sk->sk_state == TCP_TIME_WAIT) { | |
9469c7b4 | 448 | inet_twsk_put(inet_twsk(sk)); |
32bbd879 | 449 | return 0; |
1da177e4 | 450 | } |
26e37360 | 451 | seq = ntohl(th->seq); |
32bbd879 SB |
452 | if (sk->sk_state == TCP_NEW_SYN_RECV) { |
453 | tcp_req_err(sk, seq, type == ICMP_PARAMETERPROB || | |
454 | type == ICMP_TIME_EXCEEDED || | |
455 | (type == ICMP_DEST_UNREACH && | |
456 | (code == ICMP_NET_UNREACH || | |
457 | code == ICMP_HOST_UNREACH))); | |
458 | return 0; | |
459 | } | |
1da177e4 LT |
460 | |
461 | bh_lock_sock(sk); | |
462 | /* If too many ICMPs get dropped on busy | |
463 | * servers this needs to be solved differently. | |
563d34d0 ED |
464 | * We do take care of PMTU discovery (RFC1191) special case : |
465 | * we can receive locally generated ICMP messages while socket is held. | |
1da177e4 | 466 | */ |
b74aa930 ED |
467 | if (sock_owned_by_user(sk)) { |
468 | if (!(type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)) | |
02a1d6e7 | 469 | __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); |
b74aa930 | 470 | } |
1da177e4 LT |
471 | if (sk->sk_state == TCP_CLOSE) |
472 | goto out; | |
473 | ||
97e3ecd1 | 474 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
02a1d6e7 | 475 | __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP); |
97e3ecd1 | 476 | goto out; |
477 | } | |
478 | ||
f1ecd5d9 | 479 | icsk = inet_csk(sk); |
1da177e4 | 480 | tp = tcp_sk(sk); |
0a672f74 | 481 | /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */ |
d983ea6f | 482 | fastopen = rcu_dereference(tp->fastopen_rsk); |
0a672f74 | 483 | snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; |
1da177e4 | 484 | if (sk->sk_state != TCP_LISTEN && |
0a672f74 | 485 | !between(seq, snd_una, tp->snd_nxt)) { |
02a1d6e7 | 486 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
1da177e4 LT |
487 | goto out; |
488 | } | |
489 | ||
490 | switch (type) { | |
55be7a9c | 491 | case ICMP_REDIRECT: |
45caeaa5 JM |
492 | if (!sock_owned_by_user(sk)) |
493 | do_redirect(icmp_skb, sk); | |
55be7a9c | 494 | goto out; |
1da177e4 LT |
495 | case ICMP_SOURCE_QUENCH: |
496 | /* Just silently ignore these. */ | |
497 | goto out; | |
498 | case ICMP_PARAMETERPROB: | |
499 | err = EPROTO; | |
500 | break; | |
501 | case ICMP_DEST_UNREACH: | |
502 | if (code > NR_ICMP_UNREACH) | |
503 | goto out; | |
504 | ||
505 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ | |
0d4f0608 ED |
506 | /* We are not interested in TCP_LISTEN and open_requests |
507 | * (SYN-ACKs send out by Linux are always <576bytes so | |
508 | * they should go through unfragmented). | |
509 | */ | |
510 | if (sk->sk_state == TCP_LISTEN) | |
511 | goto out; | |
512 | ||
563d34d0 | 513 | tp->mtu_info = info; |
144d56e9 | 514 | if (!sock_owned_by_user(sk)) { |
563d34d0 | 515 | tcp_v4_mtu_reduced(sk); |
144d56e9 | 516 | } else { |
7aa5470c | 517 | if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &sk->sk_tsq_flags)) |
144d56e9 ED |
518 | sock_hold(sk); |
519 | } | |
1da177e4 LT |
520 | goto out; |
521 | } | |
522 | ||
523 | err = icmp_err_convert[code].errno; | |
f1ecd5d9 DL |
524 | /* check if icmp_skb allows revert of backoff |
525 | * (see draft-zimmermann-tcp-lcd) */ | |
526 | if (code != ICMP_NET_UNREACH && code != ICMP_HOST_UNREACH) | |
527 | break; | |
528 | if (seq != tp->snd_una || !icsk->icsk_retransmits || | |
0a672f74 | 529 | !icsk->icsk_backoff || fastopen) |
f1ecd5d9 DL |
530 | break; |
531 | ||
8f49c270 DM |
532 | if (sock_owned_by_user(sk)) |
533 | break; | |
534 | ||
2c4cc971 ED |
535 | skb = tcp_rtx_queue_head(sk); |
536 | if (WARN_ON_ONCE(!skb)) | |
537 | break; | |
538 | ||
f1ecd5d9 | 539 | icsk->icsk_backoff--; |
fcdd1cf4 ED |
540 | icsk->icsk_rto = tp->srtt_us ? __tcp_set_rto(tp) : |
541 | TCP_TIMEOUT_INIT; | |
542 | icsk->icsk_rto = inet_csk_rto_backoff(icsk, TCP_RTO_MAX); | |
f1ecd5d9 | 543 | |
f1ecd5d9 | 544 | |
9a568de4 | 545 | tcp_mstamp_refresh(tp); |
2fd66ffb | 546 | delta_us = (u32)(tp->tcp_mstamp - tcp_skb_timestamp_us(skb)); |
7faee5c0 | 547 | remaining = icsk->icsk_rto - |
9a568de4 | 548 | usecs_to_jiffies(delta_us); |
f1ecd5d9 | 549 | |
9a568de4 | 550 | if (remaining > 0) { |
f1ecd5d9 DL |
551 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, |
552 | remaining, TCP_RTO_MAX); | |
f1ecd5d9 DL |
553 | } else { |
554 | /* RTO revert clocked out retransmission. | |
555 | * Will retransmit now */ | |
556 | tcp_retransmit_timer(sk); | |
557 | } | |
558 | ||
1da177e4 LT |
559 | break; |
560 | case ICMP_TIME_EXCEEDED: | |
561 | err = EHOSTUNREACH; | |
562 | break; | |
563 | default: | |
564 | goto out; | |
565 | } | |
566 | ||
567 | switch (sk->sk_state) { | |
1da177e4 | 568 | case TCP_SYN_SENT: |
0a672f74 YC |
569 | case TCP_SYN_RECV: |
570 | /* Only in fast or simultaneous open. If a fast open socket is | |
571 | * is already accepted it is treated as a connected one below. | |
572 | */ | |
51456b29 | 573 | if (fastopen && !fastopen->sk) |
0a672f74 YC |
574 | break; |
575 | ||
1da177e4 | 576 | if (!sock_owned_by_user(sk)) { |
1da177e4 LT |
577 | sk->sk_err = err; |
578 | ||
579 | sk->sk_error_report(sk); | |
580 | ||
581 | tcp_done(sk); | |
582 | } else { | |
583 | sk->sk_err_soft = err; | |
584 | } | |
585 | goto out; | |
586 | } | |
587 | ||
588 | /* If we've already connected we will keep trying | |
589 | * until we time out, or the user gives up. | |
590 | * | |
591 | * rfc1122 4.2.3.9 allows to consider as hard errors | |
592 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, | |
593 | * but it is obsoleted by pmtu discovery). | |
594 | * | |
595 | * Note, that in modern internet, where routing is unreliable | |
596 | * and in each dark corner broken firewalls sit, sending random | |
597 | * errors ordered by their masters even this two messages finally lose | |
598 | * their original sense (even Linux sends invalid PORT_UNREACHs) | |
599 | * | |
600 | * Now we are in compliance with RFCs. | |
601 | * --ANK (980905) | |
602 | */ | |
603 | ||
604 | inet = inet_sk(sk); | |
605 | if (!sock_owned_by_user(sk) && inet->recverr) { | |
606 | sk->sk_err = err; | |
607 | sk->sk_error_report(sk); | |
608 | } else { /* Only an error on timeout */ | |
609 | sk->sk_err_soft = err; | |
610 | } | |
611 | ||
612 | out: | |
613 | bh_unlock_sock(sk); | |
614 | sock_put(sk); | |
32bbd879 | 615 | return 0; |
1da177e4 LT |
616 | } |
617 | ||
28850dc7 | 618 | void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr) |
1da177e4 | 619 | { |
aa8223c7 | 620 | struct tcphdr *th = tcp_hdr(skb); |
1da177e4 | 621 | |
98be9b12 ED |
622 | th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0); |
623 | skb->csum_start = skb_transport_header(skb) - skb->head; | |
624 | skb->csum_offset = offsetof(struct tcphdr, check); | |
1da177e4 LT |
625 | } |
626 | ||
419f9f89 | 627 | /* This routine computes an IPv4 TCP checksum. */ |
bb296246 | 628 | void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb) |
419f9f89 | 629 | { |
cf533ea5 | 630 | const struct inet_sock *inet = inet_sk(sk); |
419f9f89 HX |
631 | |
632 | __tcp_v4_send_check(skb, inet->inet_saddr, inet->inet_daddr); | |
633 | } | |
4bc2f18b | 634 | EXPORT_SYMBOL(tcp_v4_send_check); |
419f9f89 | 635 | |
1da177e4 LT |
636 | /* |
637 | * This routine will send an RST to the other tcp. | |
638 | * | |
639 | * Someone asks: why I NEVER use socket parameters (TOS, TTL etc.) | |
640 | * for reset. | |
641 | * Answer: if a packet caused RST, it is not for a socket | |
642 | * existing in our system, if it is matched to a socket, | |
643 | * it is just duplicate segment or bug in other side's TCP. | |
644 | * So that we build reply only basing on parameters | |
645 | * arrived with segment. | |
646 | * Exception: precedence violation. We do not implement it in any case. | |
647 | */ | |
648 | ||
a00e7444 | 649 | static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) |
1da177e4 | 650 | { |
cf533ea5 | 651 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
652 | struct { |
653 | struct tcphdr th; | |
654 | #ifdef CONFIG_TCP_MD5SIG | |
714e85be | 655 | __be32 opt[(TCPOLEN_MD5SIG_ALIGNED >> 2)]; |
cfb6eeb4 YH |
656 | #endif |
657 | } rep; | |
1da177e4 | 658 | struct ip_reply_arg arg; |
cfb6eeb4 | 659 | #ifdef CONFIG_TCP_MD5SIG |
e46787f0 | 660 | struct tcp_md5sig_key *key = NULL; |
658ddaaf SL |
661 | const __u8 *hash_location = NULL; |
662 | unsigned char newhash[16]; | |
663 | int genhash; | |
664 | struct sock *sk1 = NULL; | |
cfb6eeb4 | 665 | #endif |
d6fb396c | 666 | u64 transmit_time = 0; |
00483690 | 667 | struct sock *ctl_sk; |
d6fb396c | 668 | struct net *net; |
1da177e4 LT |
669 | |
670 | /* Never send a reset in response to a reset. */ | |
671 | if (th->rst) | |
672 | return; | |
673 | ||
c3658e8d ED |
674 | /* If sk not NULL, it means we did a successful lookup and incoming |
675 | * route had to be correct. prequeue might have dropped our dst. | |
676 | */ | |
677 | if (!sk && skb_rtable(skb)->rt_type != RTN_LOCAL) | |
1da177e4 LT |
678 | return; |
679 | ||
680 | /* Swap the send and the receive. */ | |
cfb6eeb4 YH |
681 | memset(&rep, 0, sizeof(rep)); |
682 | rep.th.dest = th->source; | |
683 | rep.th.source = th->dest; | |
684 | rep.th.doff = sizeof(struct tcphdr) / 4; | |
685 | rep.th.rst = 1; | |
1da177e4 LT |
686 | |
687 | if (th->ack) { | |
cfb6eeb4 | 688 | rep.th.seq = th->ack_seq; |
1da177e4 | 689 | } else { |
cfb6eeb4 YH |
690 | rep.th.ack = 1; |
691 | rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin + | |
692 | skb->len - (th->doff << 2)); | |
1da177e4 LT |
693 | } |
694 | ||
7174259e | 695 | memset(&arg, 0, sizeof(arg)); |
cfb6eeb4 YH |
696 | arg.iov[0].iov_base = (unsigned char *)&rep; |
697 | arg.iov[0].iov_len = sizeof(rep.th); | |
698 | ||
0f85feae | 699 | net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev); |
cfb6eeb4 | 700 | #ifdef CONFIG_TCP_MD5SIG |
3b24d854 | 701 | rcu_read_lock(); |
658ddaaf | 702 | hash_location = tcp_parse_md5sig_option(th); |
271c3b9b | 703 | if (sk && sk_fullsock(sk)) { |
cea97609 | 704 | const union tcp_md5_addr *addr; |
dea53bb8 | 705 | int l3index; |
cea97609 | 706 | |
dea53bb8 DA |
707 | /* sdif set, means packet ingressed via a device |
708 | * in an L3 domain and inet_iif is set to it. | |
709 | */ | |
710 | l3index = tcp_v4_sdif(skb) ? inet_iif(skb) : 0; | |
cea97609 | 711 | addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; |
dea53bb8 | 712 | key = tcp_md5_do_lookup(sk, l3index, addr, AF_INET); |
e46787f0 | 713 | } else if (hash_location) { |
cea97609 | 714 | const union tcp_md5_addr *addr; |
534322ca DA |
715 | int sdif = tcp_v4_sdif(skb); |
716 | int dif = inet_iif(skb); | |
dea53bb8 | 717 | int l3index; |
cea97609 | 718 | |
658ddaaf SL |
719 | /* |
720 | * active side is lost. Try to find listening socket through | |
721 | * source port, and then find md5 key through listening socket. | |
722 | * we are not loose security here: | |
723 | * Incoming packet is checked with md5 hash with finding key, | |
724 | * no RST generated if md5 hash doesn't match. | |
725 | */ | |
a583636a CG |
726 | sk1 = __inet_lookup_listener(net, &tcp_hashinfo, NULL, 0, |
727 | ip_hdr(skb)->saddr, | |
da5e3630 | 728 | th->source, ip_hdr(skb)->daddr, |
534322ca | 729 | ntohs(th->source), dif, sdif); |
658ddaaf SL |
730 | /* don't send rst if it can't find key */ |
731 | if (!sk1) | |
3b24d854 ED |
732 | goto out; |
733 | ||
dea53bb8 DA |
734 | /* sdif set, means packet ingressed via a device |
735 | * in an L3 domain and dif is set to it. | |
736 | */ | |
737 | l3index = sdif ? dif : 0; | |
cea97609 | 738 | addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; |
dea53bb8 | 739 | key = tcp_md5_do_lookup(sk1, l3index, addr, AF_INET); |
658ddaaf | 740 | if (!key) |
3b24d854 ED |
741 | goto out; |
742 | ||
658ddaaf | 743 | |
39f8e58e | 744 | genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb); |
658ddaaf | 745 | if (genhash || memcmp(hash_location, newhash, 16) != 0) |
3b24d854 ED |
746 | goto out; |
747 | ||
658ddaaf SL |
748 | } |
749 | ||
cfb6eeb4 YH |
750 | if (key) { |
751 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | | |
752 | (TCPOPT_NOP << 16) | | |
753 | (TCPOPT_MD5SIG << 8) | | |
754 | TCPOLEN_MD5SIG); | |
755 | /* Update length and the length the header thinks exists */ | |
756 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
757 | rep.th.doff = arg.iov[0].iov_len / 4; | |
758 | ||
49a72dfb | 759 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[1], |
78e645cb IJ |
760 | key, ip_hdr(skb)->saddr, |
761 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
762 | } |
763 | #endif | |
eddc9ec5 ACM |
764 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
765 | ip_hdr(skb)->saddr, /* XXX */ | |
52cd5750 | 766 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
1da177e4 | 767 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; |
271c3b9b FW |
768 | arg.flags = (sk && inet_sk_transparent(sk)) ? IP_REPLY_ARG_NOSRCCHECK : 0; |
769 | ||
e2446eaa | 770 | /* When socket is gone, all binding information is lost. |
4c675258 AK |
771 | * routing might fail in this case. No choice here, if we choose to force |
772 | * input interface, we will misroute in case of asymmetric route. | |
e2446eaa | 773 | */ |
c24b14c4 | 774 | if (sk) { |
4c675258 | 775 | arg.bound_dev_if = sk->sk_bound_dev_if; |
5c487bb9 SL |
776 | if (sk_fullsock(sk)) |
777 | trace_tcp_send_reset(sk, skb); | |
c24b14c4 | 778 | } |
1da177e4 | 779 | |
271c3b9b FW |
780 | BUILD_BUG_ON(offsetof(struct sock, sk_bound_dev_if) != |
781 | offsetof(struct inet_timewait_sock, tw_bound_dev_if)); | |
782 | ||
66b13d99 | 783 | arg.tos = ip_hdr(skb)->tos; |
e2d118a1 | 784 | arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL); |
47dcc20a | 785 | local_bh_disable(); |
5472c3c6 | 786 | ctl_sk = this_cpu_read(*net->ipv4.tcp_sk); |
a842fe14 | 787 | if (sk) { |
00483690 JM |
788 | ctl_sk->sk_mark = (sk->sk_state == TCP_TIME_WAIT) ? |
789 | inet_twsk(sk)->tw_mark : sk->sk_mark; | |
f6c0f5d2 ED |
790 | ctl_sk->sk_priority = (sk->sk_state == TCP_TIME_WAIT) ? |
791 | inet_twsk(sk)->tw_priority : sk->sk_priority; | |
d6fb396c | 792 | transmit_time = tcp_transmit_time(sk); |
a842fe14 | 793 | } |
00483690 | 794 | ip_send_unicast_reply(ctl_sk, |
bdbbb852 | 795 | skb, &TCP_SKB_CB(skb)->header.h4.opt, |
24a2d43d | 796 | ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, |
d6fb396c ED |
797 | &arg, arg.iov[0].iov_len, |
798 | transmit_time); | |
1da177e4 | 799 | |
00483690 | 800 | ctl_sk->sk_mark = 0; |
90bbcc60 ED |
801 | __TCP_INC_STATS(net, TCP_MIB_OUTSEGS); |
802 | __TCP_INC_STATS(net, TCP_MIB_OUTRSTS); | |
47dcc20a | 803 | local_bh_enable(); |
658ddaaf SL |
804 | |
805 | #ifdef CONFIG_TCP_MD5SIG | |
3b24d854 ED |
806 | out: |
807 | rcu_read_unlock(); | |
658ddaaf | 808 | #endif |
1da177e4 LT |
809 | } |
810 | ||
811 | /* The code following below sending ACKs in SYN-RECV and TIME-WAIT states | |
812 | outside socket context is ugly, certainly. What can I do? | |
813 | */ | |
814 | ||
e2d118a1 | 815 | static void tcp_v4_send_ack(const struct sock *sk, |
e62a123b | 816 | struct sk_buff *skb, u32 seq, u32 ack, |
ee684b6f | 817 | u32 win, u32 tsval, u32 tsecr, int oif, |
88ef4a5a | 818 | struct tcp_md5sig_key *key, |
66b13d99 | 819 | int reply_flags, u8 tos) |
1da177e4 | 820 | { |
cf533ea5 | 821 | const struct tcphdr *th = tcp_hdr(skb); |
1da177e4 LT |
822 | struct { |
823 | struct tcphdr th; | |
714e85be | 824 | __be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2) |
cfb6eeb4 | 825 | #ifdef CONFIG_TCP_MD5SIG |
714e85be | 826 | + (TCPOLEN_MD5SIG_ALIGNED >> 2) |
cfb6eeb4 YH |
827 | #endif |
828 | ]; | |
1da177e4 | 829 | } rep; |
e2d118a1 | 830 | struct net *net = sock_net(sk); |
1da177e4 | 831 | struct ip_reply_arg arg; |
00483690 | 832 | struct sock *ctl_sk; |
d6fb396c | 833 | u64 transmit_time; |
1da177e4 LT |
834 | |
835 | memset(&rep.th, 0, sizeof(struct tcphdr)); | |
7174259e | 836 | memset(&arg, 0, sizeof(arg)); |
1da177e4 LT |
837 | |
838 | arg.iov[0].iov_base = (unsigned char *)&rep; | |
839 | arg.iov[0].iov_len = sizeof(rep.th); | |
ee684b6f | 840 | if (tsecr) { |
cfb6eeb4 YH |
841 | rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | |
842 | (TCPOPT_TIMESTAMP << 8) | | |
843 | TCPOLEN_TIMESTAMP); | |
ee684b6f AV |
844 | rep.opt[1] = htonl(tsval); |
845 | rep.opt[2] = htonl(tsecr); | |
cb48cfe8 | 846 | arg.iov[0].iov_len += TCPOLEN_TSTAMP_ALIGNED; |
1da177e4 LT |
847 | } |
848 | ||
849 | /* Swap the send and the receive. */ | |
850 | rep.th.dest = th->source; | |
851 | rep.th.source = th->dest; | |
852 | rep.th.doff = arg.iov[0].iov_len / 4; | |
853 | rep.th.seq = htonl(seq); | |
854 | rep.th.ack_seq = htonl(ack); | |
855 | rep.th.ack = 1; | |
856 | rep.th.window = htons(win); | |
857 | ||
cfb6eeb4 | 858 | #ifdef CONFIG_TCP_MD5SIG |
cfb6eeb4 | 859 | if (key) { |
ee684b6f | 860 | int offset = (tsecr) ? 3 : 0; |
cfb6eeb4 YH |
861 | |
862 | rep.opt[offset++] = htonl((TCPOPT_NOP << 24) | | |
863 | (TCPOPT_NOP << 16) | | |
864 | (TCPOPT_MD5SIG << 8) | | |
865 | TCPOLEN_MD5SIG); | |
866 | arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED; | |
867 | rep.th.doff = arg.iov[0].iov_len/4; | |
868 | ||
49a72dfb | 869 | tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[offset], |
90b7e112 AL |
870 | key, ip_hdr(skb)->saddr, |
871 | ip_hdr(skb)->daddr, &rep.th); | |
cfb6eeb4 YH |
872 | } |
873 | #endif | |
88ef4a5a | 874 | arg.flags = reply_flags; |
eddc9ec5 ACM |
875 | arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr, |
876 | ip_hdr(skb)->saddr, /* XXX */ | |
1da177e4 LT |
877 | arg.iov[0].iov_len, IPPROTO_TCP, 0); |
878 | arg.csumoffset = offsetof(struct tcphdr, check) / 2; | |
9501f972 YH |
879 | if (oif) |
880 | arg.bound_dev_if = oif; | |
66b13d99 | 881 | arg.tos = tos; |
e2d118a1 | 882 | arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL); |
47dcc20a | 883 | local_bh_disable(); |
5472c3c6 | 884 | ctl_sk = this_cpu_read(*net->ipv4.tcp_sk); |
a842fe14 ED |
885 | ctl_sk->sk_mark = (sk->sk_state == TCP_TIME_WAIT) ? |
886 | inet_twsk(sk)->tw_mark : sk->sk_mark; | |
f6c0f5d2 ED |
887 | ctl_sk->sk_priority = (sk->sk_state == TCP_TIME_WAIT) ? |
888 | inet_twsk(sk)->tw_priority : sk->sk_priority; | |
d6fb396c | 889 | transmit_time = tcp_transmit_time(sk); |
00483690 | 890 | ip_send_unicast_reply(ctl_sk, |
bdbbb852 | 891 | skb, &TCP_SKB_CB(skb)->header.h4.opt, |
24a2d43d | 892 | ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, |
d6fb396c ED |
893 | &arg, arg.iov[0].iov_len, |
894 | transmit_time); | |
1da177e4 | 895 | |
00483690 | 896 | ctl_sk->sk_mark = 0; |
90bbcc60 | 897 | __TCP_INC_STATS(net, TCP_MIB_OUTSEGS); |
47dcc20a | 898 | local_bh_enable(); |
1da177e4 LT |
899 | } |
900 | ||
901 | static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) | |
902 | { | |
8feaf0c0 | 903 | struct inet_timewait_sock *tw = inet_twsk(sk); |
cfb6eeb4 | 904 | struct tcp_timewait_sock *tcptw = tcp_twsk(sk); |
1da177e4 | 905 | |
e2d118a1 | 906 | tcp_v4_send_ack(sk, skb, |
e62a123b | 907 | tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, |
7174259e | 908 | tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, |
9a568de4 | 909 | tcp_time_stamp_raw() + tcptw->tw_ts_offset, |
9501f972 YH |
910 | tcptw->tw_ts_recent, |
911 | tw->tw_bound_dev_if, | |
88ef4a5a | 912 | tcp_twsk_md5_key(tcptw), |
66b13d99 ED |
913 | tw->tw_transparent ? IP_REPLY_ARG_NOSRCCHECK : 0, |
914 | tw->tw_tos | |
9501f972 | 915 | ); |
1da177e4 | 916 | |
8feaf0c0 | 917 | inet_twsk_put(tw); |
1da177e4 LT |
918 | } |
919 | ||
a00e7444 | 920 | static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, |
7174259e | 921 | struct request_sock *req) |
1da177e4 | 922 | { |
cea97609 | 923 | const union tcp_md5_addr *addr; |
dea53bb8 | 924 | int l3index; |
cea97609 | 925 | |
168a8f58 JC |
926 | /* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV |
927 | * sk->sk_state == TCP_SYN_RECV -> for Fast Open. | |
928 | */ | |
e62a123b ED |
929 | u32 seq = (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 : |
930 | tcp_sk(sk)->snd_nxt; | |
931 | ||
20a2b49f ED |
932 | /* RFC 7323 2.3 |
933 | * The window field (SEG.WND) of every outgoing segment, with the | |
934 | * exception of <SYN> segments, MUST be right-shifted by | |
935 | * Rcv.Wind.Shift bits: | |
936 | */ | |
cea97609 | 937 | addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr; |
dea53bb8 | 938 | l3index = tcp_v4_sdif(skb) ? inet_iif(skb) : 0; |
e2d118a1 | 939 | tcp_v4_send_ack(sk, skb, seq, |
20a2b49f ED |
940 | tcp_rsk(req)->rcv_nxt, |
941 | req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, | |
9a568de4 | 942 | tcp_time_stamp_raw() + tcp_rsk(req)->ts_off, |
9501f972 YH |
943 | req->ts_recent, |
944 | 0, | |
dea53bb8 | 945 | tcp_md5_do_lookup(sk, l3index, addr, AF_INET), |
66b13d99 ED |
946 | inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0, |
947 | ip_hdr(skb)->tos); | |
1da177e4 LT |
948 | } |
949 | ||
1da177e4 | 950 | /* |
9bf1d83e | 951 | * Send a SYN-ACK after having received a SYN. |
60236fdd | 952 | * This still operates on a request_sock only, not on a big |
1da177e4 LT |
953 | * socket. |
954 | */ | |
0f935dbe | 955 | static int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst, |
d6274bd8 | 956 | struct flowi *fl, |
72659ecc | 957 | struct request_sock *req, |
ca6fb065 | 958 | struct tcp_fastopen_cookie *foc, |
b3d05147 | 959 | enum tcp_synack_type synack_type) |
1da177e4 | 960 | { |
2e6599cb | 961 | const struct inet_request_sock *ireq = inet_rsk(req); |
6bd023f3 | 962 | struct flowi4 fl4; |
1da177e4 | 963 | int err = -1; |
d41db5af | 964 | struct sk_buff *skb; |
1da177e4 LT |
965 | |
966 | /* First, grab a route. */ | |
ba3f7f04 | 967 | if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL) |
fd80eb94 | 968 | return -1; |
1da177e4 | 969 | |
b3d05147 | 970 | skb = tcp_make_synack(sk, dst, req, foc, synack_type); |
1da177e4 LT |
971 | |
972 | if (skb) { | |
634fb979 | 973 | __tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr); |
1da177e4 | 974 | |
2ab2ddd3 | 975 | rcu_read_lock(); |
634fb979 ED |
976 | err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr, |
977 | ireq->ir_rmt_addr, | |
2ab2ddd3 ED |
978 | rcu_dereference(ireq->ireq_opt)); |
979 | rcu_read_unlock(); | |
b9df3cb8 | 980 | err = net_xmit_eval(err); |
1da177e4 LT |
981 | } |
982 | ||
1da177e4 LT |
983 | return err; |
984 | } | |
985 | ||
986 | /* | |
60236fdd | 987 | * IPv4 request_sock destructor. |
1da177e4 | 988 | */ |
60236fdd | 989 | static void tcp_v4_reqsk_destructor(struct request_sock *req) |
1da177e4 | 990 | { |
c92e8c02 | 991 | kfree(rcu_dereference_protected(inet_rsk(req)->ireq_opt, 1)); |
1da177e4 LT |
992 | } |
993 | ||
cfb6eeb4 YH |
994 | #ifdef CONFIG_TCP_MD5SIG |
995 | /* | |
996 | * RFC2385 MD5 checksumming requires a mapping of | |
997 | * IP address->MD5 Key. | |
998 | * We need to maintain these in the sk structure. | |
999 | */ | |
1000 | ||
921f9a0f | 1001 | DEFINE_STATIC_KEY_FALSE(tcp_md5_needed); |
6015c71e ED |
1002 | EXPORT_SYMBOL(tcp_md5_needed); |
1003 | ||
cfb6eeb4 | 1004 | /* Find the Key structure for an address. */ |
dea53bb8 | 1005 | struct tcp_md5sig_key *__tcp_md5_do_lookup(const struct sock *sk, int l3index, |
6015c71e ED |
1006 | const union tcp_md5_addr *addr, |
1007 | int family) | |
cfb6eeb4 | 1008 | { |
fd3a154a | 1009 | const struct tcp_sock *tp = tcp_sk(sk); |
a915da9b | 1010 | struct tcp_md5sig_key *key; |
fd3a154a | 1011 | const struct tcp_md5sig_info *md5sig; |
6797318e ID |
1012 | __be32 mask; |
1013 | struct tcp_md5sig_key *best_match = NULL; | |
1014 | bool match; | |
cfb6eeb4 | 1015 | |
a8afca03 ED |
1016 | /* caller either holds rcu_read_lock() or socket lock */ |
1017 | md5sig = rcu_dereference_check(tp->md5sig_info, | |
1e1d04e6 | 1018 | lockdep_sock_is_held(sk)); |
a8afca03 | 1019 | if (!md5sig) |
cfb6eeb4 | 1020 | return NULL; |
083a0326 | 1021 | |
c8b91770 AG |
1022 | hlist_for_each_entry_rcu(key, &md5sig->head, node, |
1023 | lockdep_sock_is_held(sk)) { | |
a915da9b ED |
1024 | if (key->family != family) |
1025 | continue; | |
dea53bb8 DA |
1026 | if (key->l3index && key->l3index != l3index) |
1027 | continue; | |
6797318e ID |
1028 | if (family == AF_INET) { |
1029 | mask = inet_make_mask(key->prefixlen); | |
1030 | match = (key->addr.a4.s_addr & mask) == | |
1031 | (addr->a4.s_addr & mask); | |
1032 | #if IS_ENABLED(CONFIG_IPV6) | |
1033 | } else if (family == AF_INET6) { | |
1034 | match = ipv6_prefix_equal(&key->addr.a6, &addr->a6, | |
1035 | key->prefixlen); | |
1036 | #endif | |
1037 | } else { | |
1038 | match = false; | |
1039 | } | |
1040 | ||
1041 | if (match && (!best_match || | |
1042 | key->prefixlen > best_match->prefixlen)) | |
1043 | best_match = key; | |
1044 | } | |
1045 | return best_match; | |
1046 | } | |
6015c71e | 1047 | EXPORT_SYMBOL(__tcp_md5_do_lookup); |
6797318e | 1048 | |
e8f37d57 WF |
1049 | static struct tcp_md5sig_key *tcp_md5_do_lookup_exact(const struct sock *sk, |
1050 | const union tcp_md5_addr *addr, | |
dea53bb8 DA |
1051 | int family, u8 prefixlen, |
1052 | int l3index) | |
6797318e ID |
1053 | { |
1054 | const struct tcp_sock *tp = tcp_sk(sk); | |
1055 | struct tcp_md5sig_key *key; | |
1056 | unsigned int size = sizeof(struct in_addr); | |
1057 | const struct tcp_md5sig_info *md5sig; | |
1058 | ||
1059 | /* caller either holds rcu_read_lock() or socket lock */ | |
1060 | md5sig = rcu_dereference_check(tp->md5sig_info, | |
1061 | lockdep_sock_is_held(sk)); | |
1062 | if (!md5sig) | |
1063 | return NULL; | |
1064 | #if IS_ENABLED(CONFIG_IPV6) | |
1065 | if (family == AF_INET6) | |
1066 | size = sizeof(struct in6_addr); | |
1067 | #endif | |
c8b91770 AG |
1068 | hlist_for_each_entry_rcu(key, &md5sig->head, node, |
1069 | lockdep_sock_is_held(sk)) { | |
6797318e ID |
1070 | if (key->family != family) |
1071 | continue; | |
dea53bb8 DA |
1072 | if (key->l3index && key->l3index != l3index) |
1073 | continue; | |
6797318e ID |
1074 | if (!memcmp(&key->addr, addr, size) && |
1075 | key->prefixlen == prefixlen) | |
a915da9b | 1076 | return key; |
cfb6eeb4 YH |
1077 | } |
1078 | return NULL; | |
1079 | } | |
1080 | ||
b83e3deb | 1081 | struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk, |
fd3a154a | 1082 | const struct sock *addr_sk) |
cfb6eeb4 | 1083 | { |
b52e6921 | 1084 | const union tcp_md5_addr *addr; |
dea53bb8 | 1085 | int l3index; |
a915da9b | 1086 | |
dea53bb8 DA |
1087 | l3index = l3mdev_master_ifindex_by_index(sock_net(sk), |
1088 | addr_sk->sk_bound_dev_if); | |
b52e6921 | 1089 | addr = (const union tcp_md5_addr *)&addr_sk->sk_daddr; |
dea53bb8 | 1090 | return tcp_md5_do_lookup(sk, l3index, addr, AF_INET); |
cfb6eeb4 | 1091 | } |
cfb6eeb4 YH |
1092 | EXPORT_SYMBOL(tcp_v4_md5_lookup); |
1093 | ||
cfb6eeb4 | 1094 | /* This can be called on a newly created socket, from other files */ |
a915da9b | 1095 | int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, |
dea53bb8 DA |
1096 | int family, u8 prefixlen, int l3index, |
1097 | const u8 *newkey, u8 newkeylen, gfp_t gfp) | |
cfb6eeb4 YH |
1098 | { |
1099 | /* Add Key to the list */ | |
b0a713e9 | 1100 | struct tcp_md5sig_key *key; |
cfb6eeb4 | 1101 | struct tcp_sock *tp = tcp_sk(sk); |
a915da9b | 1102 | struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 1103 | |
dea53bb8 | 1104 | key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen, l3index); |
cfb6eeb4 YH |
1105 | if (key) { |
1106 | /* Pre-existing entry - just update that one. */ | |
a915da9b | 1107 | memcpy(key->key, newkey, newkeylen); |
b0a713e9 | 1108 | key->keylen = newkeylen; |
a915da9b ED |
1109 | return 0; |
1110 | } | |
260fcbeb | 1111 | |
a8afca03 | 1112 | md5sig = rcu_dereference_protected(tp->md5sig_info, |
1e1d04e6 | 1113 | lockdep_sock_is_held(sk)); |
a915da9b ED |
1114 | if (!md5sig) { |
1115 | md5sig = kmalloc(sizeof(*md5sig), gfp); | |
1116 | if (!md5sig) | |
cfb6eeb4 | 1117 | return -ENOMEM; |
cfb6eeb4 | 1118 | |
a915da9b ED |
1119 | sk_nocaps_add(sk, NETIF_F_GSO_MASK); |
1120 | INIT_HLIST_HEAD(&md5sig->head); | |
a8afca03 | 1121 | rcu_assign_pointer(tp->md5sig_info, md5sig); |
a915da9b | 1122 | } |
cfb6eeb4 | 1123 | |
5f3d9cb2 | 1124 | key = sock_kmalloc(sk, sizeof(*key), gfp); |
a915da9b ED |
1125 | if (!key) |
1126 | return -ENOMEM; | |
71cea17e | 1127 | if (!tcp_alloc_md5sig_pool()) { |
5f3d9cb2 | 1128 | sock_kfree_s(sk, key, sizeof(*key)); |
a915da9b | 1129 | return -ENOMEM; |
cfb6eeb4 | 1130 | } |
a915da9b ED |
1131 | |
1132 | memcpy(key->key, newkey, newkeylen); | |
1133 | key->keylen = newkeylen; | |
1134 | key->family = family; | |
6797318e | 1135 | key->prefixlen = prefixlen; |
dea53bb8 | 1136 | key->l3index = l3index; |
a915da9b ED |
1137 | memcpy(&key->addr, addr, |
1138 | (family == AF_INET6) ? sizeof(struct in6_addr) : | |
1139 | sizeof(struct in_addr)); | |
1140 | hlist_add_head_rcu(&key->node, &md5sig->head); | |
cfb6eeb4 YH |
1141 | return 0; |
1142 | } | |
a915da9b | 1143 | EXPORT_SYMBOL(tcp_md5_do_add); |
cfb6eeb4 | 1144 | |
6797318e | 1145 | int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family, |
dea53bb8 | 1146 | u8 prefixlen, int l3index) |
cfb6eeb4 | 1147 | { |
a915da9b ED |
1148 | struct tcp_md5sig_key *key; |
1149 | ||
dea53bb8 | 1150 | key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen, l3index); |
a915da9b ED |
1151 | if (!key) |
1152 | return -ENOENT; | |
1153 | hlist_del_rcu(&key->node); | |
5f3d9cb2 | 1154 | atomic_sub(sizeof(*key), &sk->sk_omem_alloc); |
a915da9b | 1155 | kfree_rcu(key, rcu); |
a915da9b | 1156 | return 0; |
cfb6eeb4 | 1157 | } |
a915da9b | 1158 | EXPORT_SYMBOL(tcp_md5_do_del); |
cfb6eeb4 | 1159 | |
e0683e70 | 1160 | static void tcp_clear_md5_list(struct sock *sk) |
cfb6eeb4 YH |
1161 | { |
1162 | struct tcp_sock *tp = tcp_sk(sk); | |
a915da9b | 1163 | struct tcp_md5sig_key *key; |
b67bfe0d | 1164 | struct hlist_node *n; |
a8afca03 | 1165 | struct tcp_md5sig_info *md5sig; |
cfb6eeb4 | 1166 | |
a8afca03 ED |
1167 | md5sig = rcu_dereference_protected(tp->md5sig_info, 1); |
1168 | ||
b67bfe0d | 1169 | hlist_for_each_entry_safe(key, n, &md5sig->head, node) { |
a915da9b | 1170 | hlist_del_rcu(&key->node); |
5f3d9cb2 | 1171 | atomic_sub(sizeof(*key), &sk->sk_omem_alloc); |
a915da9b | 1172 | kfree_rcu(key, rcu); |
cfb6eeb4 YH |
1173 | } |
1174 | } | |
1175 | ||
8917a777 ID |
1176 | static int tcp_v4_parse_md5_keys(struct sock *sk, int optname, |
1177 | char __user *optval, int optlen) | |
cfb6eeb4 YH |
1178 | { |
1179 | struct tcp_md5sig cmd; | |
1180 | struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr; | |
cea97609 | 1181 | const union tcp_md5_addr *addr; |
8917a777 | 1182 | u8 prefixlen = 32; |
dea53bb8 | 1183 | int l3index = 0; |
cfb6eeb4 YH |
1184 | |
1185 | if (optlen < sizeof(cmd)) | |
1186 | return -EINVAL; | |
1187 | ||
7174259e | 1188 | if (copy_from_user(&cmd, optval, sizeof(cmd))) |
cfb6eeb4 YH |
1189 | return -EFAULT; |
1190 | ||
1191 | if (sin->sin_family != AF_INET) | |
1192 | return -EINVAL; | |
1193 | ||
8917a777 ID |
1194 | if (optname == TCP_MD5SIG_EXT && |
1195 | cmd.tcpm_flags & TCP_MD5SIG_FLAG_PREFIX) { | |
1196 | prefixlen = cmd.tcpm_prefixlen; | |
1197 | if (prefixlen > 32) | |
1198 | return -EINVAL; | |
1199 | } | |
1200 | ||
6b102db5 DA |
1201 | if (optname == TCP_MD5SIG_EXT && |
1202 | cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX) { | |
1203 | struct net_device *dev; | |
1204 | ||
1205 | rcu_read_lock(); | |
1206 | dev = dev_get_by_index_rcu(sock_net(sk), cmd.tcpm_ifindex); | |
1207 | if (dev && netif_is_l3_master(dev)) | |
1208 | l3index = dev->ifindex; | |
1209 | ||
1210 | rcu_read_unlock(); | |
1211 | ||
1212 | /* ok to reference set/not set outside of rcu; | |
1213 | * right now device MUST be an L3 master | |
1214 | */ | |
1215 | if (!dev || !l3index) | |
1216 | return -EINVAL; | |
1217 | } | |
1218 | ||
cea97609 DA |
1219 | addr = (union tcp_md5_addr *)&sin->sin_addr.s_addr; |
1220 | ||
64a124ed | 1221 | if (!cmd.tcpm_keylen) |
dea53bb8 | 1222 | return tcp_md5_do_del(sk, addr, AF_INET, prefixlen, l3index); |
cfb6eeb4 YH |
1223 | |
1224 | if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) | |
1225 | return -EINVAL; | |
1226 | ||
dea53bb8 | 1227 | return tcp_md5_do_add(sk, addr, AF_INET, prefixlen, l3index, |
cea97609 | 1228 | cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); |
cfb6eeb4 YH |
1229 | } |
1230 | ||
19689e38 ED |
1231 | static int tcp_v4_md5_hash_headers(struct tcp_md5sig_pool *hp, |
1232 | __be32 daddr, __be32 saddr, | |
1233 | const struct tcphdr *th, int nbytes) | |
cfb6eeb4 | 1234 | { |
cfb6eeb4 | 1235 | struct tcp4_pseudohdr *bp; |
49a72dfb | 1236 | struct scatterlist sg; |
19689e38 | 1237 | struct tcphdr *_th; |
cfb6eeb4 | 1238 | |
19689e38 | 1239 | bp = hp->scratch; |
cfb6eeb4 YH |
1240 | bp->saddr = saddr; |
1241 | bp->daddr = daddr; | |
1242 | bp->pad = 0; | |
076fb722 | 1243 | bp->protocol = IPPROTO_TCP; |
49a72dfb | 1244 | bp->len = cpu_to_be16(nbytes); |
c7da57a1 | 1245 | |
19689e38 ED |
1246 | _th = (struct tcphdr *)(bp + 1); |
1247 | memcpy(_th, th, sizeof(*th)); | |
1248 | _th->check = 0; | |
1249 | ||
1250 | sg_init_one(&sg, bp, sizeof(*bp) + sizeof(*th)); | |
1251 | ahash_request_set_crypt(hp->md5_req, &sg, NULL, | |
1252 | sizeof(*bp) + sizeof(*th)); | |
cf80e0e4 | 1253 | return crypto_ahash_update(hp->md5_req); |
49a72dfb AL |
1254 | } |
1255 | ||
a915da9b | 1256 | static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key, |
318cf7aa | 1257 | __be32 daddr, __be32 saddr, const struct tcphdr *th) |
49a72dfb AL |
1258 | { |
1259 | struct tcp_md5sig_pool *hp; | |
cf80e0e4 | 1260 | struct ahash_request *req; |
49a72dfb AL |
1261 | |
1262 | hp = tcp_get_md5sig_pool(); | |
1263 | if (!hp) | |
1264 | goto clear_hash_noput; | |
cf80e0e4 | 1265 | req = hp->md5_req; |
49a72dfb | 1266 | |
cf80e0e4 | 1267 | if (crypto_ahash_init(req)) |
49a72dfb | 1268 | goto clear_hash; |
19689e38 | 1269 | if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, th->doff << 2)) |
49a72dfb AL |
1270 | goto clear_hash; |
1271 | if (tcp_md5_hash_key(hp, key)) | |
1272 | goto clear_hash; | |
cf80e0e4 HX |
1273 | ahash_request_set_crypt(req, NULL, md5_hash, 0); |
1274 | if (crypto_ahash_final(req)) | |
cfb6eeb4 YH |
1275 | goto clear_hash; |
1276 | ||
cfb6eeb4 | 1277 | tcp_put_md5sig_pool(); |
cfb6eeb4 | 1278 | return 0; |
49a72dfb | 1279 | |
cfb6eeb4 YH |
1280 | clear_hash: |
1281 | tcp_put_md5sig_pool(); | |
1282 | clear_hash_noput: | |
1283 | memset(md5_hash, 0, 16); | |
49a72dfb | 1284 | return 1; |
cfb6eeb4 YH |
1285 | } |
1286 | ||
39f8e58e ED |
1287 | int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key, |
1288 | const struct sock *sk, | |
318cf7aa | 1289 | const struct sk_buff *skb) |
cfb6eeb4 | 1290 | { |
49a72dfb | 1291 | struct tcp_md5sig_pool *hp; |
cf80e0e4 | 1292 | struct ahash_request *req; |
318cf7aa | 1293 | const struct tcphdr *th = tcp_hdr(skb); |
cfb6eeb4 YH |
1294 | __be32 saddr, daddr; |
1295 | ||
39f8e58e ED |
1296 | if (sk) { /* valid for establish/request sockets */ |
1297 | saddr = sk->sk_rcv_saddr; | |
1298 | daddr = sk->sk_daddr; | |
cfb6eeb4 | 1299 | } else { |
49a72dfb AL |
1300 | const struct iphdr *iph = ip_hdr(skb); |
1301 | saddr = iph->saddr; | |
1302 | daddr = iph->daddr; | |
cfb6eeb4 | 1303 | } |
49a72dfb AL |
1304 | |
1305 | hp = tcp_get_md5sig_pool(); | |
1306 | if (!hp) | |
1307 | goto clear_hash_noput; | |
cf80e0e4 | 1308 | req = hp->md5_req; |
49a72dfb | 1309 | |
cf80e0e4 | 1310 | if (crypto_ahash_init(req)) |
49a72dfb AL |
1311 | goto clear_hash; |
1312 | ||
19689e38 | 1313 | if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, skb->len)) |
49a72dfb AL |
1314 | goto clear_hash; |
1315 | if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2)) | |
1316 | goto clear_hash; | |
1317 | if (tcp_md5_hash_key(hp, key)) | |
1318 | goto clear_hash; | |
cf80e0e4 HX |
1319 | ahash_request_set_crypt(req, NULL, md5_hash, 0); |
1320 | if (crypto_ahash_final(req)) | |
49a72dfb AL |
1321 | goto clear_hash; |
1322 | ||
1323 | tcp_put_md5sig_pool(); | |
1324 | return 0; | |
1325 | ||
1326 | clear_hash: | |
1327 | tcp_put_md5sig_pool(); | |
1328 | clear_hash_noput: | |
1329 | memset(md5_hash, 0, 16); | |
1330 | return 1; | |
cfb6eeb4 | 1331 | } |
49a72dfb | 1332 | EXPORT_SYMBOL(tcp_v4_md5_hash_skb); |
cfb6eeb4 | 1333 | |
ba8e275a ED |
1334 | #endif |
1335 | ||
ff74e23f | 1336 | /* Called with rcu_read_lock() */ |
ba8e275a | 1337 | static bool tcp_v4_inbound_md5_hash(const struct sock *sk, |
534322ca DA |
1338 | const struct sk_buff *skb, |
1339 | int dif, int sdif) | |
cfb6eeb4 | 1340 | { |
ba8e275a | 1341 | #ifdef CONFIG_TCP_MD5SIG |
cfb6eeb4 YH |
1342 | /* |
1343 | * This gets called for each TCP segment that arrives | |
1344 | * so we want to be efficient. | |
1345 | * We have 3 drop cases: | |
1346 | * o No MD5 hash and one expected. | |
1347 | * o MD5 hash and we're not expecting one. | |
1348 | * o MD5 hash and its wrong. | |
1349 | */ | |
cf533ea5 | 1350 | const __u8 *hash_location = NULL; |
cfb6eeb4 | 1351 | struct tcp_md5sig_key *hash_expected; |
eddc9ec5 | 1352 | const struct iphdr *iph = ip_hdr(skb); |
cf533ea5 | 1353 | const struct tcphdr *th = tcp_hdr(skb); |
cea97609 | 1354 | const union tcp_md5_addr *addr; |
cfb6eeb4 | 1355 | unsigned char newhash[16]; |
dea53bb8 DA |
1356 | int genhash, l3index; |
1357 | ||
1358 | /* sdif set, means packet ingressed via a device | |
1359 | * in an L3 domain and dif is set to the l3mdev | |
1360 | */ | |
1361 | l3index = sdif ? dif : 0; | |
cfb6eeb4 | 1362 | |
cea97609 | 1363 | addr = (union tcp_md5_addr *)&iph->saddr; |
dea53bb8 | 1364 | hash_expected = tcp_md5_do_lookup(sk, l3index, addr, AF_INET); |
7d5d5525 | 1365 | hash_location = tcp_parse_md5sig_option(th); |
cfb6eeb4 | 1366 | |
cfb6eeb4 YH |
1367 | /* We've parsed the options - do we have a hash? */ |
1368 | if (!hash_expected && !hash_location) | |
a2a385d6 | 1369 | return false; |
cfb6eeb4 YH |
1370 | |
1371 | if (hash_expected && !hash_location) { | |
c10d9310 | 1372 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); |
a2a385d6 | 1373 | return true; |
cfb6eeb4 YH |
1374 | } |
1375 | ||
1376 | if (!hash_expected && hash_location) { | |
c10d9310 | 1377 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); |
a2a385d6 | 1378 | return true; |
cfb6eeb4 YH |
1379 | } |
1380 | ||
1381 | /* Okay, so this is hash_expected and hash_location - | |
1382 | * so we need to calculate the checksum. | |
1383 | */ | |
49a72dfb AL |
1384 | genhash = tcp_v4_md5_hash_skb(newhash, |
1385 | hash_expected, | |
39f8e58e | 1386 | NULL, skb); |
cfb6eeb4 YH |
1387 | |
1388 | if (genhash || memcmp(hash_location, newhash, 16) != 0) { | |
72145a68 | 1389 | NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); |
dea53bb8 | 1390 | net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s L3 index %d\n", |
e87cc472 JP |
1391 | &iph->saddr, ntohs(th->source), |
1392 | &iph->daddr, ntohs(th->dest), | |
1393 | genhash ? " tcp_v4_calc_md5_hash failed" | |
dea53bb8 | 1394 | : "", l3index); |
a2a385d6 | 1395 | return true; |
cfb6eeb4 | 1396 | } |
a2a385d6 | 1397 | return false; |
cfb6eeb4 | 1398 | #endif |
ba8e275a ED |
1399 | return false; |
1400 | } | |
cfb6eeb4 | 1401 | |
b40cf18e ED |
1402 | static void tcp_v4_init_req(struct request_sock *req, |
1403 | const struct sock *sk_listener, | |
16bea70a OP |
1404 | struct sk_buff *skb) |
1405 | { | |
1406 | struct inet_request_sock *ireq = inet_rsk(req); | |
c92e8c02 | 1407 | struct net *net = sock_net(sk_listener); |
16bea70a | 1408 | |
08d2cc3b ED |
1409 | sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); |
1410 | sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); | |
c92e8c02 | 1411 | RCU_INIT_POINTER(ireq->ireq_opt, tcp_v4_save_options(net, skb)); |
16bea70a OP |
1412 | } |
1413 | ||
f964629e ED |
1414 | static struct dst_entry *tcp_v4_route_req(const struct sock *sk, |
1415 | struct flowi *fl, | |
4396e461 | 1416 | const struct request_sock *req) |
d94e0417 | 1417 | { |
4396e461 | 1418 | return inet_csk_route_req(sk, &fl->u.ip4, req); |
d94e0417 OP |
1419 | } |
1420 | ||
72a3effa | 1421 | struct request_sock_ops tcp_request_sock_ops __read_mostly = { |
1da177e4 | 1422 | .family = PF_INET, |
2e6599cb | 1423 | .obj_size = sizeof(struct tcp_request_sock), |
5db92c99 | 1424 | .rtx_syn_ack = tcp_rtx_synack, |
60236fdd ACM |
1425 | .send_ack = tcp_v4_reqsk_send_ack, |
1426 | .destructor = tcp_v4_reqsk_destructor, | |
1da177e4 | 1427 | .send_reset = tcp_v4_send_reset, |
688d1945 | 1428 | .syn_ack_timeout = tcp_syn_ack_timeout, |
1da177e4 LT |
1429 | }; |
1430 | ||
35b2c321 | 1431 | const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { |
2aec4a29 | 1432 | .mss_clamp = TCP_MSS_DEFAULT, |
16bea70a | 1433 | #ifdef CONFIG_TCP_MD5SIG |
fd3a154a | 1434 | .req_md5_lookup = tcp_v4_md5_lookup, |
e3afe7b7 | 1435 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
b6332e6c | 1436 | #endif |
16bea70a | 1437 | .init_req = tcp_v4_init_req, |
fb7b37a7 OP |
1438 | #ifdef CONFIG_SYN_COOKIES |
1439 | .cookie_init_seq = cookie_v4_init_sequence, | |
1440 | #endif | |
d94e0417 | 1441 | .route_req = tcp_v4_route_req, |
84b114b9 ED |
1442 | .init_seq = tcp_v4_init_seq, |
1443 | .init_ts_off = tcp_v4_init_ts_off, | |
d6274bd8 | 1444 | .send_synack = tcp_v4_send_synack, |
16bea70a | 1445 | }; |
cfb6eeb4 | 1446 | |
1da177e4 LT |
1447 | int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
1448 | { | |
1da177e4 | 1449 | /* Never answer to SYNs send to broadcast or multicast */ |
511c3f92 | 1450 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
1da177e4 LT |
1451 | goto drop; |
1452 | ||
1fb6f159 OP |
1453 | return tcp_conn_request(&tcp_request_sock_ops, |
1454 | &tcp_request_sock_ipv4_ops, sk, skb); | |
1da177e4 | 1455 | |
1da177e4 | 1456 | drop: |
9caad864 | 1457 | tcp_listendrop(sk); |
1da177e4 LT |
1458 | return 0; |
1459 | } | |
4bc2f18b | 1460 | EXPORT_SYMBOL(tcp_v4_conn_request); |
1da177e4 LT |
1461 | |
1462 | ||
1463 | /* | |
1464 | * The three way handshake has completed - we got a valid synack - | |
1465 | * now create the new socket. | |
1466 | */ | |
0c27171e | 1467 | struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, |
60236fdd | 1468 | struct request_sock *req, |
5e0724d0 ED |
1469 | struct dst_entry *dst, |
1470 | struct request_sock *req_unhash, | |
1471 | bool *own_req) | |
1da177e4 | 1472 | { |
2e6599cb | 1473 | struct inet_request_sock *ireq; |
1da177e4 LT |
1474 | struct inet_sock *newinet; |
1475 | struct tcp_sock *newtp; | |
1476 | struct sock *newsk; | |
cfb6eeb4 | 1477 | #ifdef CONFIG_TCP_MD5SIG |
cea97609 | 1478 | const union tcp_md5_addr *addr; |
cfb6eeb4 | 1479 | struct tcp_md5sig_key *key; |
dea53bb8 | 1480 | int l3index; |
cfb6eeb4 | 1481 | #endif |
f6d8bd05 | 1482 | struct ip_options_rcu *inet_opt; |
1da177e4 LT |
1483 | |
1484 | if (sk_acceptq_is_full(sk)) | |
1485 | goto exit_overflow; | |
1486 | ||
1da177e4 LT |
1487 | newsk = tcp_create_openreq_child(sk, req, skb); |
1488 | if (!newsk) | |
093d2823 | 1489 | goto exit_nonewsk; |
1da177e4 | 1490 | |
bcd76111 | 1491 | newsk->sk_gso_type = SKB_GSO_TCPV4; |
fae6ef87 | 1492 | inet_sk_rx_dst_set(newsk, skb); |
1da177e4 LT |
1493 | |
1494 | newtp = tcp_sk(newsk); | |
1495 | newinet = inet_sk(newsk); | |
2e6599cb | 1496 | ireq = inet_rsk(req); |
d1e559d0 ED |
1497 | sk_daddr_set(newsk, ireq->ir_rmt_addr); |
1498 | sk_rcv_saddr_set(newsk, ireq->ir_loc_addr); | |
6dd9a14e | 1499 | newsk->sk_bound_dev_if = ireq->ir_iif; |
c92e8c02 ED |
1500 | newinet->inet_saddr = ireq->ir_loc_addr; |
1501 | inet_opt = rcu_dereference(ireq->ireq_opt); | |
1502 | RCU_INIT_POINTER(newinet->inet_opt, inet_opt); | |
463c84b9 | 1503 | newinet->mc_index = inet_iif(skb); |
eddc9ec5 | 1504 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
4c507d28 | 1505 | newinet->rcv_tos = ip_hdr(skb)->tos; |
d83d8461 | 1506 | inet_csk(newsk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
1507 | if (inet_opt) |
1508 | inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
a904a069 | 1509 | newinet->inet_id = prandom_u32(); |
1da177e4 | 1510 | |
dfd25fff ED |
1511 | if (!dst) { |
1512 | dst = inet_csk_route_child_sock(sk, newsk, req); | |
1513 | if (!dst) | |
1514 | goto put_and_exit; | |
1515 | } else { | |
1516 | /* syncookie case : see end of cookie_v4_check() */ | |
1517 | } | |
0e734419 DM |
1518 | sk_setup_caps(newsk, dst); |
1519 | ||
81164413 DB |
1520 | tcp_ca_openreq_child(newsk, dst); |
1521 | ||
1da177e4 | 1522 | tcp_sync_mss(newsk, dst_mtu(dst)); |
3541f9e8 | 1523 | newtp->advmss = tcp_mss_clamp(tcp_sk(sk), dst_metric_advmss(dst)); |
f5fff5dc | 1524 | |
1da177e4 LT |
1525 | tcp_initialize_rcv_mss(newsk); |
1526 | ||
cfb6eeb4 | 1527 | #ifdef CONFIG_TCP_MD5SIG |
dea53bb8 | 1528 | l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif); |
cfb6eeb4 | 1529 | /* Copy over the MD5 key from the original socket */ |
cea97609 | 1530 | addr = (union tcp_md5_addr *)&newinet->inet_daddr; |
dea53bb8 | 1531 | key = tcp_md5_do_lookup(sk, l3index, addr, AF_INET); |
00db4124 | 1532 | if (key) { |
cfb6eeb4 YH |
1533 | /* |
1534 | * We're using one, so create a matching key | |
1535 | * on the newsk structure. If we fail to get | |
1536 | * memory, then we end up not copying the key | |
1537 | * across. Shucks. | |
1538 | */ | |
dea53bb8 | 1539 | tcp_md5_do_add(newsk, addr, AF_INET, 32, l3index, |
cea97609 | 1540 | key->key, key->keylen, GFP_ATOMIC); |
a465419b | 1541 | sk_nocaps_add(newsk, NETIF_F_GSO_MASK); |
cfb6eeb4 YH |
1542 | } |
1543 | #endif | |
1544 | ||
0e734419 DM |
1545 | if (__inet_inherit_port(sk, newsk) < 0) |
1546 | goto put_and_exit; | |
5e0724d0 | 1547 | *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash)); |
c92e8c02 | 1548 | if (likely(*own_req)) { |
49a496c9 | 1549 | tcp_move_syn(newtp, req); |
c92e8c02 ED |
1550 | ireq->ireq_opt = NULL; |
1551 | } else { | |
1552 | newinet->inet_opt = NULL; | |
1553 | } | |
1da177e4 LT |
1554 | return newsk; |
1555 | ||
1556 | exit_overflow: | |
c10d9310 | 1557 | NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
093d2823 BS |
1558 | exit_nonewsk: |
1559 | dst_release(dst); | |
1da177e4 | 1560 | exit: |
9caad864 | 1561 | tcp_listendrop(sk); |
1da177e4 | 1562 | return NULL; |
0e734419 | 1563 | put_and_exit: |
c92e8c02 | 1564 | newinet->inet_opt = NULL; |
e337e24d CP |
1565 | inet_csk_prepare_forced_close(newsk); |
1566 | tcp_done(newsk); | |
0e734419 | 1567 | goto exit; |
1da177e4 | 1568 | } |
4bc2f18b | 1569 | EXPORT_SYMBOL(tcp_v4_syn_recv_sock); |
1da177e4 | 1570 | |
079096f1 | 1571 | static struct sock *tcp_v4_cookie_check(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 1572 | { |
079096f1 | 1573 | #ifdef CONFIG_SYN_COOKIES |
52452c54 | 1574 | const struct tcphdr *th = tcp_hdr(skb); |
1da177e4 | 1575 | |
af9b4738 | 1576 | if (!th->syn) |
461b74c3 | 1577 | sk = cookie_v4_check(sk, skb); |
1da177e4 LT |
1578 | #endif |
1579 | return sk; | |
1580 | } | |
1581 | ||
9349d600 PP |
1582 | u16 tcp_v4_get_syncookie(struct sock *sk, struct iphdr *iph, |
1583 | struct tcphdr *th, u32 *cookie) | |
1584 | { | |
1585 | u16 mss = 0; | |
1586 | #ifdef CONFIG_SYN_COOKIES | |
1587 | mss = tcp_get_syncookie_mss(&tcp_request_sock_ops, | |
1588 | &tcp_request_sock_ipv4_ops, sk, th); | |
1589 | if (mss) { | |
1590 | *cookie = __cookie_v4_init_sequence(iph, th, &mss); | |
1591 | tcp_synq_overflow(sk); | |
1592 | } | |
1593 | #endif | |
1594 | return mss; | |
1595 | } | |
1596 | ||
1da177e4 | 1597 | /* The socket must have it's spinlock held when we get |
e994b2f0 | 1598 | * here, unless it is a TCP_LISTEN socket. |
1da177e4 LT |
1599 | * |
1600 | * We have a potential double-lock case here, so even when | |
1601 | * doing backlog processing we use the BH locking scheme. | |
1602 | * This is because we cannot sleep with the original spinlock | |
1603 | * held. | |
1604 | */ | |
1605 | int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) | |
1606 | { | |
cfb6eeb4 | 1607 | struct sock *rsk; |
cfb6eeb4 | 1608 | |
1da177e4 | 1609 | if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ |
404e0a8b ED |
1610 | struct dst_entry *dst = sk->sk_rx_dst; |
1611 | ||
bdeab991 | 1612 | sock_rps_save_rxhash(sk, skb); |
3d97379a | 1613 | sk_mark_napi_id(sk, skb); |
404e0a8b | 1614 | if (dst) { |
505fbcf0 | 1615 | if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif || |
51456b29 | 1616 | !dst->ops->check(dst, 0)) { |
92101b3b DM |
1617 | dst_release(dst); |
1618 | sk->sk_rx_dst = NULL; | |
1619 | } | |
1620 | } | |
3d97d88e | 1621 | tcp_rcv_established(sk, skb); |
1da177e4 LT |
1622 | return 0; |
1623 | } | |
1624 | ||
12e25e10 | 1625 | if (tcp_checksum_complete(skb)) |
1da177e4 LT |
1626 | goto csum_err; |
1627 | ||
1628 | if (sk->sk_state == TCP_LISTEN) { | |
079096f1 ED |
1629 | struct sock *nsk = tcp_v4_cookie_check(sk, skb); |
1630 | ||
1da177e4 LT |
1631 | if (!nsk) |
1632 | goto discard; | |
1da177e4 | 1633 | if (nsk != sk) { |
cfb6eeb4 YH |
1634 | if (tcp_child_process(sk, nsk, skb)) { |
1635 | rsk = nsk; | |
1da177e4 | 1636 | goto reset; |
cfb6eeb4 | 1637 | } |
1da177e4 LT |
1638 | return 0; |
1639 | } | |
ca55158c | 1640 | } else |
bdeab991 | 1641 | sock_rps_save_rxhash(sk, skb); |
ca55158c | 1642 | |
72ab4a86 | 1643 | if (tcp_rcv_state_process(sk, skb)) { |
cfb6eeb4 | 1644 | rsk = sk; |
1da177e4 | 1645 | goto reset; |
cfb6eeb4 | 1646 | } |
1da177e4 LT |
1647 | return 0; |
1648 | ||
1649 | reset: | |
cfb6eeb4 | 1650 | tcp_v4_send_reset(rsk, skb); |
1da177e4 LT |
1651 | discard: |
1652 | kfree_skb(skb); | |
1653 | /* Be careful here. If this function gets more complicated and | |
1654 | * gcc suffers from register pressure on the x86, sk (in %ebx) | |
1655 | * might be destroyed here. This current version compiles correctly, | |
1656 | * but you have been warned. | |
1657 | */ | |
1658 | return 0; | |
1659 | ||
1660 | csum_err: | |
c10d9310 ED |
1661 | TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); |
1662 | TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); | |
1da177e4 LT |
1663 | goto discard; |
1664 | } | |
4bc2f18b | 1665 | EXPORT_SYMBOL(tcp_v4_do_rcv); |
1da177e4 | 1666 | |
7487449c | 1667 | int tcp_v4_early_demux(struct sk_buff *skb) |
41063e9d | 1668 | { |
41063e9d DM |
1669 | const struct iphdr *iph; |
1670 | const struct tcphdr *th; | |
1671 | struct sock *sk; | |
41063e9d | 1672 | |
41063e9d | 1673 | if (skb->pkt_type != PACKET_HOST) |
7487449c | 1674 | return 0; |
41063e9d | 1675 | |
45f00f99 | 1676 | if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) |
7487449c | 1677 | return 0; |
41063e9d DM |
1678 | |
1679 | iph = ip_hdr(skb); | |
45f00f99 | 1680 | th = tcp_hdr(skb); |
41063e9d DM |
1681 | |
1682 | if (th->doff < sizeof(struct tcphdr) / 4) | |
7487449c | 1683 | return 0; |
41063e9d | 1684 | |
45f00f99 | 1685 | sk = __inet_lookup_established(dev_net(skb->dev), &tcp_hashinfo, |
41063e9d | 1686 | iph->saddr, th->source, |
7011d085 | 1687 | iph->daddr, ntohs(th->dest), |
3fa6f616 | 1688 | skb->skb_iif, inet_sdif(skb)); |
41063e9d DM |
1689 | if (sk) { |
1690 | skb->sk = sk; | |
1691 | skb->destructor = sock_edemux; | |
f7e4eb03 | 1692 | if (sk_fullsock(sk)) { |
d0c294c5 | 1693 | struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst); |
505fbcf0 | 1694 | |
41063e9d DM |
1695 | if (dst) |
1696 | dst = dst_check(dst, 0); | |
92101b3b | 1697 | if (dst && |
505fbcf0 | 1698 | inet_sk(sk)->rx_dst_ifindex == skb->skb_iif) |
92101b3b | 1699 | skb_dst_set_noref(skb, dst); |
41063e9d DM |
1700 | } |
1701 | } | |
7487449c | 1702 | return 0; |
41063e9d DM |
1703 | } |
1704 | ||
c9c33212 ED |
1705 | bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) |
1706 | { | |
8265792b | 1707 | u32 limit = READ_ONCE(sk->sk_rcvbuf) + READ_ONCE(sk->sk_sndbuf); |
4f693b55 ED |
1708 | struct skb_shared_info *shinfo; |
1709 | const struct tcphdr *th; | |
1710 | struct tcphdr *thtail; | |
1711 | struct sk_buff *tail; | |
1712 | unsigned int hdrlen; | |
1713 | bool fragstolen; | |
1714 | u32 gso_segs; | |
1715 | int delta; | |
c9c33212 ED |
1716 | |
1717 | /* In case all data was pulled from skb frags (in __pskb_pull_tail()), | |
1718 | * we can fix skb->truesize to its real value to avoid future drops. | |
1719 | * This is valid because skb is not yet charged to the socket. | |
1720 | * It has been noticed pure SACK packets were sometimes dropped | |
1721 | * (if cooked by drivers without copybreak feature). | |
1722 | */ | |
60b1af33 | 1723 | skb_condense(skb); |
c9c33212 | 1724 | |
ade9628e ED |
1725 | skb_dst_drop(skb); |
1726 | ||
4f693b55 ED |
1727 | if (unlikely(tcp_checksum_complete(skb))) { |
1728 | bh_unlock_sock(sk); | |
1729 | __TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS); | |
1730 | __TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); | |
1731 | return true; | |
1732 | } | |
1733 | ||
1734 | /* Attempt coalescing to last skb in backlog, even if we are | |
1735 | * above the limits. | |
1736 | * This is okay because skb capacity is limited to MAX_SKB_FRAGS. | |
1737 | */ | |
1738 | th = (const struct tcphdr *)skb->data; | |
1739 | hdrlen = th->doff * 4; | |
1740 | shinfo = skb_shinfo(skb); | |
1741 | ||
1742 | if (!shinfo->gso_size) | |
1743 | shinfo->gso_size = skb->len - hdrlen; | |
1744 | ||
1745 | if (!shinfo->gso_segs) | |
1746 | shinfo->gso_segs = 1; | |
1747 | ||
1748 | tail = sk->sk_backlog.tail; | |
1749 | if (!tail) | |
1750 | goto no_coalesce; | |
1751 | thtail = (struct tcphdr *)tail->data; | |
1752 | ||
1753 | if (TCP_SKB_CB(tail)->end_seq != TCP_SKB_CB(skb)->seq || | |
1754 | TCP_SKB_CB(tail)->ip_dsfield != TCP_SKB_CB(skb)->ip_dsfield || | |
1755 | ((TCP_SKB_CB(tail)->tcp_flags | | |
ca2fe295 ED |
1756 | TCP_SKB_CB(skb)->tcp_flags) & (TCPHDR_SYN | TCPHDR_RST | TCPHDR_URG)) || |
1757 | !((TCP_SKB_CB(tail)->tcp_flags & | |
1758 | TCP_SKB_CB(skb)->tcp_flags) & TCPHDR_ACK) || | |
4f693b55 ED |
1759 | ((TCP_SKB_CB(tail)->tcp_flags ^ |
1760 | TCP_SKB_CB(skb)->tcp_flags) & (TCPHDR_ECE | TCPHDR_CWR)) || | |
1761 | #ifdef CONFIG_TLS_DEVICE | |
1762 | tail->decrypted != skb->decrypted || | |
1763 | #endif | |
1764 | thtail->doff != th->doff || | |
1765 | memcmp(thtail + 1, th + 1, hdrlen - sizeof(*th))) | |
1766 | goto no_coalesce; | |
1767 | ||
1768 | __skb_pull(skb, hdrlen); | |
1769 | if (skb_try_coalesce(tail, skb, &fragstolen, &delta)) { | |
1770 | thtail->window = th->window; | |
1771 | ||
1772 | TCP_SKB_CB(tail)->end_seq = TCP_SKB_CB(skb)->end_seq; | |
1773 | ||
1774 | if (after(TCP_SKB_CB(skb)->ack_seq, TCP_SKB_CB(tail)->ack_seq)) | |
1775 | TCP_SKB_CB(tail)->ack_seq = TCP_SKB_CB(skb)->ack_seq; | |
1776 | ||
ca2fe295 ED |
1777 | /* We have to update both TCP_SKB_CB(tail)->tcp_flags and |
1778 | * thtail->fin, so that the fast path in tcp_rcv_established() | |
1779 | * is not entered if we append a packet with a FIN. | |
1780 | * SYN, RST, URG are not present. | |
1781 | * ACK is set on both packets. | |
1782 | * PSH : we do not really care in TCP stack, | |
1783 | * at least for 'GRO' packets. | |
1784 | */ | |
1785 | thtail->fin |= th->fin; | |
4f693b55 ED |
1786 | TCP_SKB_CB(tail)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags; |
1787 | ||
1788 | if (TCP_SKB_CB(skb)->has_rxtstamp) { | |
1789 | TCP_SKB_CB(tail)->has_rxtstamp = true; | |
1790 | tail->tstamp = skb->tstamp; | |
1791 | skb_hwtstamps(tail)->hwtstamp = skb_hwtstamps(skb)->hwtstamp; | |
1792 | } | |
1793 | ||
1794 | /* Not as strict as GRO. We only need to carry mss max value */ | |
1795 | skb_shinfo(tail)->gso_size = max(shinfo->gso_size, | |
1796 | skb_shinfo(tail)->gso_size); | |
1797 | ||
1798 | gso_segs = skb_shinfo(tail)->gso_segs + shinfo->gso_segs; | |
1799 | skb_shinfo(tail)->gso_segs = min_t(u32, gso_segs, 0xFFFF); | |
1800 | ||
1801 | sk->sk_backlog.len += delta; | |
1802 | __NET_INC_STATS(sock_net(sk), | |
1803 | LINUX_MIB_TCPBACKLOGCOALESCE); | |
1804 | kfree_skb_partial(skb, fragstolen); | |
1805 | return false; | |
1806 | } | |
1807 | __skb_push(skb, hdrlen); | |
1808 | ||
1809 | no_coalesce: | |
1810 | /* Only socket owner can try to collapse/prune rx queues | |
1811 | * to reduce memory overhead, so add a little headroom here. | |
1812 | * Few sockets backlog are possibly concurrently non empty. | |
1813 | */ | |
1814 | limit += 64*1024; | |
1815 | ||
c9c33212 ED |
1816 | if (unlikely(sk_add_backlog(sk, skb, limit))) { |
1817 | bh_unlock_sock(sk); | |
1818 | __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPBACKLOGDROP); | |
1819 | return true; | |
1820 | } | |
1821 | return false; | |
1822 | } | |
1823 | EXPORT_SYMBOL(tcp_add_backlog); | |
1824 | ||
ac6e7800 ED |
1825 | int tcp_filter(struct sock *sk, struct sk_buff *skb) |
1826 | { | |
1827 | struct tcphdr *th = (struct tcphdr *)skb->data; | |
ac6e7800 | 1828 | |
f2feaefd | 1829 | return sk_filter_trim_cap(sk, skb, th->doff * 4); |
ac6e7800 ED |
1830 | } |
1831 | EXPORT_SYMBOL(tcp_filter); | |
1832 | ||
eeea10b8 ED |
1833 | static void tcp_v4_restore_cb(struct sk_buff *skb) |
1834 | { | |
1835 | memmove(IPCB(skb), &TCP_SKB_CB(skb)->header.h4, | |
1836 | sizeof(struct inet_skb_parm)); | |
1837 | } | |
1838 | ||
1839 | static void tcp_v4_fill_cb(struct sk_buff *skb, const struct iphdr *iph, | |
1840 | const struct tcphdr *th) | |
1841 | { | |
1842 | /* This is tricky : We move IPCB at its correct location into TCP_SKB_CB() | |
1843 | * barrier() makes sure compiler wont play fool^Waliasing games. | |
1844 | */ | |
1845 | memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb), | |
1846 | sizeof(struct inet_skb_parm)); | |
1847 | barrier(); | |
1848 | ||
1849 | TCP_SKB_CB(skb)->seq = ntohl(th->seq); | |
1850 | TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + | |
1851 | skb->len - th->doff * 4); | |
1852 | TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); | |
1853 | TCP_SKB_CB(skb)->tcp_flags = tcp_flag_byte(th); | |
1854 | TCP_SKB_CB(skb)->tcp_tw_isn = 0; | |
1855 | TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph); | |
1856 | TCP_SKB_CB(skb)->sacked = 0; | |
1857 | TCP_SKB_CB(skb)->has_rxtstamp = | |
1858 | skb->tstamp || skb_hwtstamps(skb)->hwtstamp; | |
1859 | } | |
1860 | ||
1da177e4 LT |
1861 | /* |
1862 | * From tcp_input.c | |
1863 | */ | |
1864 | ||
1865 | int tcp_v4_rcv(struct sk_buff *skb) | |
1866 | { | |
3b24d854 | 1867 | struct net *net = dev_net(skb->dev); |
8b27dae5 | 1868 | struct sk_buff *skb_to_free; |
3fa6f616 | 1869 | int sdif = inet_sdif(skb); |
534322ca | 1870 | int dif = inet_iif(skb); |
eddc9ec5 | 1871 | const struct iphdr *iph; |
cf533ea5 | 1872 | const struct tcphdr *th; |
3b24d854 | 1873 | bool refcounted; |
1da177e4 LT |
1874 | struct sock *sk; |
1875 | int ret; | |
1876 | ||
1877 | if (skb->pkt_type != PACKET_HOST) | |
1878 | goto discard_it; | |
1879 | ||
1880 | /* Count it even if it's bad */ | |
90bbcc60 | 1881 | __TCP_INC_STATS(net, TCP_MIB_INSEGS); |
1da177e4 LT |
1882 | |
1883 | if (!pskb_may_pull(skb, sizeof(struct tcphdr))) | |
1884 | goto discard_it; | |
1885 | ||
ea1627c2 | 1886 | th = (const struct tcphdr *)skb->data; |
1da177e4 | 1887 | |
ea1627c2 | 1888 | if (unlikely(th->doff < sizeof(struct tcphdr) / 4)) |
1da177e4 LT |
1889 | goto bad_packet; |
1890 | if (!pskb_may_pull(skb, th->doff * 4)) | |
1891 | goto discard_it; | |
1892 | ||
1893 | /* An explanation is required here, I think. | |
1894 | * Packet length and doff are validated by header prediction, | |
caa20d9a | 1895 | * provided case of th->doff==0 is eliminated. |
1da177e4 | 1896 | * So, we defer the checks. */ |
ed70fcfc TH |
1897 | |
1898 | if (skb_checksum_init(skb, IPPROTO_TCP, inet_compute_pseudo)) | |
6a5dc9e5 | 1899 | goto csum_error; |
1da177e4 | 1900 | |
ea1627c2 | 1901 | th = (const struct tcphdr *)skb->data; |
eddc9ec5 | 1902 | iph = ip_hdr(skb); |
4bdc3d66 | 1903 | lookup: |
a583636a | 1904 | sk = __inet_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th), th->source, |
3fa6f616 | 1905 | th->dest, sdif, &refcounted); |
1da177e4 LT |
1906 | if (!sk) |
1907 | goto no_tcp_socket; | |
1908 | ||
bb134d5d ED |
1909 | process: |
1910 | if (sk->sk_state == TCP_TIME_WAIT) | |
1911 | goto do_time_wait; | |
1912 | ||
079096f1 ED |
1913 | if (sk->sk_state == TCP_NEW_SYN_RECV) { |
1914 | struct request_sock *req = inet_reqsk(sk); | |
e0f9759f | 1915 | bool req_stolen = false; |
7716682c | 1916 | struct sock *nsk; |
079096f1 ED |
1917 | |
1918 | sk = req->rsk_listener; | |
534322ca | 1919 | if (unlikely(tcp_v4_inbound_md5_hash(sk, skb, dif, sdif))) { |
e65c332d | 1920 | sk_drops_add(sk, skb); |
72923555 ED |
1921 | reqsk_put(req); |
1922 | goto discard_it; | |
1923 | } | |
4fd44a98 FL |
1924 | if (tcp_checksum_complete(skb)) { |
1925 | reqsk_put(req); | |
1926 | goto csum_error; | |
1927 | } | |
7716682c | 1928 | if (unlikely(sk->sk_state != TCP_LISTEN)) { |
f03f2e15 | 1929 | inet_csk_reqsk_queue_drop_and_put(sk, req); |
4bdc3d66 ED |
1930 | goto lookup; |
1931 | } | |
3b24d854 ED |
1932 | /* We own a reference on the listener, increase it again |
1933 | * as we might lose it too soon. | |
1934 | */ | |
7716682c | 1935 | sock_hold(sk); |
3b24d854 | 1936 | refcounted = true; |
1f3b359f | 1937 | nsk = NULL; |
eeea10b8 ED |
1938 | if (!tcp_filter(sk, skb)) { |
1939 | th = (const struct tcphdr *)skb->data; | |
1940 | iph = ip_hdr(skb); | |
1941 | tcp_v4_fill_cb(skb, iph, th); | |
e0f9759f | 1942 | nsk = tcp_check_req(sk, skb, req, false, &req_stolen); |
eeea10b8 | 1943 | } |
079096f1 ED |
1944 | if (!nsk) { |
1945 | reqsk_put(req); | |
e0f9759f ED |
1946 | if (req_stolen) { |
1947 | /* Another cpu got exclusive access to req | |
1948 | * and created a full blown socket. | |
1949 | * Try to feed this packet to this socket | |
1950 | * instead of discarding it. | |
1951 | */ | |
1952 | tcp_v4_restore_cb(skb); | |
1953 | sock_put(sk); | |
1954 | goto lookup; | |
1955 | } | |
7716682c | 1956 | goto discard_and_relse; |
079096f1 ED |
1957 | } |
1958 | if (nsk == sk) { | |
079096f1 | 1959 | reqsk_put(req); |
eeea10b8 | 1960 | tcp_v4_restore_cb(skb); |
079096f1 ED |
1961 | } else if (tcp_child_process(sk, nsk, skb)) { |
1962 | tcp_v4_send_reset(nsk, skb); | |
7716682c | 1963 | goto discard_and_relse; |
079096f1 | 1964 | } else { |
7716682c | 1965 | sock_put(sk); |
079096f1 ED |
1966 | return 0; |
1967 | } | |
1968 | } | |
6cce09f8 | 1969 | if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) { |
02a1d6e7 | 1970 | __NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP); |
d218d111 | 1971 | goto discard_and_relse; |
6cce09f8 | 1972 | } |
d218d111 | 1973 | |
1da177e4 LT |
1974 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
1975 | goto discard_and_relse; | |
9ea88a15 | 1976 | |
534322ca | 1977 | if (tcp_v4_inbound_md5_hash(sk, skb, dif, sdif)) |
9ea88a15 | 1978 | goto discard_and_relse; |
9ea88a15 | 1979 | |
895b5c9f | 1980 | nf_reset_ct(skb); |
1da177e4 | 1981 | |
ac6e7800 | 1982 | if (tcp_filter(sk, skb)) |
1da177e4 | 1983 | goto discard_and_relse; |
ac6e7800 ED |
1984 | th = (const struct tcphdr *)skb->data; |
1985 | iph = ip_hdr(skb); | |
eeea10b8 | 1986 | tcp_v4_fill_cb(skb, iph, th); |
1da177e4 LT |
1987 | |
1988 | skb->dev = NULL; | |
1989 | ||
e994b2f0 ED |
1990 | if (sk->sk_state == TCP_LISTEN) { |
1991 | ret = tcp_v4_do_rcv(sk, skb); | |
1992 | goto put_and_return; | |
1993 | } | |
1994 | ||
1995 | sk_incoming_cpu_update(sk); | |
1996 | ||
c6366184 | 1997 | bh_lock_sock_nested(sk); |
a44d6eac | 1998 | tcp_segs_in(tcp_sk(sk), skb); |
1da177e4 LT |
1999 | ret = 0; |
2000 | if (!sock_owned_by_user(sk)) { | |
8b27dae5 ED |
2001 | skb_to_free = sk->sk_rx_skb_cache; |
2002 | sk->sk_rx_skb_cache = NULL; | |
e7942d06 | 2003 | ret = tcp_v4_do_rcv(sk, skb); |
8b27dae5 ED |
2004 | } else { |
2005 | if (tcp_add_backlog(sk, skb)) | |
2006 | goto discard_and_relse; | |
2007 | skb_to_free = NULL; | |
6b03a53a | 2008 | } |
1da177e4 | 2009 | bh_unlock_sock(sk); |
8b27dae5 ED |
2010 | if (skb_to_free) |
2011 | __kfree_skb(skb_to_free); | |
1da177e4 | 2012 | |
e994b2f0 | 2013 | put_and_return: |
3b24d854 ED |
2014 | if (refcounted) |
2015 | sock_put(sk); | |
1da177e4 LT |
2016 | |
2017 | return ret; | |
2018 | ||
2019 | no_tcp_socket: | |
2020 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) | |
2021 | goto discard_it; | |
2022 | ||
eeea10b8 ED |
2023 | tcp_v4_fill_cb(skb, iph, th); |
2024 | ||
12e25e10 | 2025 | if (tcp_checksum_complete(skb)) { |
6a5dc9e5 | 2026 | csum_error: |
90bbcc60 | 2027 | __TCP_INC_STATS(net, TCP_MIB_CSUMERRORS); |
1da177e4 | 2028 | bad_packet: |
90bbcc60 | 2029 | __TCP_INC_STATS(net, TCP_MIB_INERRS); |
1da177e4 | 2030 | } else { |
cfb6eeb4 | 2031 | tcp_v4_send_reset(NULL, skb); |
1da177e4 LT |
2032 | } |
2033 | ||
2034 | discard_it: | |
2035 | /* Discard frame. */ | |
2036 | kfree_skb(skb); | |
e905a9ed | 2037 | return 0; |
1da177e4 LT |
2038 | |
2039 | discard_and_relse: | |
532182cd | 2040 | sk_drops_add(sk, skb); |
3b24d854 ED |
2041 | if (refcounted) |
2042 | sock_put(sk); | |
1da177e4 LT |
2043 | goto discard_it; |
2044 | ||
2045 | do_time_wait: | |
2046 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { | |
9469c7b4 | 2047 | inet_twsk_put(inet_twsk(sk)); |
1da177e4 LT |
2048 | goto discard_it; |
2049 | } | |
2050 | ||
eeea10b8 ED |
2051 | tcp_v4_fill_cb(skb, iph, th); |
2052 | ||
6a5dc9e5 ED |
2053 | if (tcp_checksum_complete(skb)) { |
2054 | inet_twsk_put(inet_twsk(sk)); | |
2055 | goto csum_error; | |
1da177e4 | 2056 | } |
9469c7b4 | 2057 | switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) { |
1da177e4 | 2058 | case TCP_TW_SYN: { |
c346dca1 | 2059 | struct sock *sk2 = inet_lookup_listener(dev_net(skb->dev), |
a583636a CG |
2060 | &tcp_hashinfo, skb, |
2061 | __tcp_hdrlen(th), | |
da5e3630 | 2062 | iph->saddr, th->source, |
eddc9ec5 | 2063 | iph->daddr, th->dest, |
3fa6f616 DA |
2064 | inet_iif(skb), |
2065 | sdif); | |
1da177e4 | 2066 | if (sk2) { |
dbe7faa4 | 2067 | inet_twsk_deschedule_put(inet_twsk(sk)); |
1da177e4 | 2068 | sk = sk2; |
eeea10b8 | 2069 | tcp_v4_restore_cb(skb); |
3b24d854 | 2070 | refcounted = false; |
1da177e4 LT |
2071 | goto process; |
2072 | } | |
1da177e4 | 2073 | } |
fcfd6dfa | 2074 | /* to ACK */ |
a8eceea8 | 2075 | fallthrough; |
1da177e4 LT |
2076 | case TCP_TW_ACK: |
2077 | tcp_v4_timewait_ack(sk, skb); | |
2078 | break; | |
2079 | case TCP_TW_RST: | |
271c3b9b FW |
2080 | tcp_v4_send_reset(sk, skb); |
2081 | inet_twsk_deschedule_put(inet_twsk(sk)); | |
2082 | goto discard_it; | |
1da177e4 LT |
2083 | case TCP_TW_SUCCESS:; |
2084 | } | |
2085 | goto discard_it; | |
2086 | } | |
2087 | ||
ccb7c410 DM |
2088 | static struct timewait_sock_ops tcp_timewait_sock_ops = { |
2089 | .twsk_obj_size = sizeof(struct tcp_timewait_sock), | |
2090 | .twsk_unique = tcp_twsk_unique, | |
2091 | .twsk_destructor= tcp_twsk_destructor, | |
ccb7c410 | 2092 | }; |
1da177e4 | 2093 | |
63d02d15 | 2094 | void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb) |
5d299f3d ED |
2095 | { |
2096 | struct dst_entry *dst = skb_dst(skb); | |
2097 | ||
5037e9ef | 2098 | if (dst && dst_hold_safe(dst)) { |
ca777eff ED |
2099 | sk->sk_rx_dst = dst; |
2100 | inet_sk(sk)->rx_dst_ifindex = skb->skb_iif; | |
2101 | } | |
5d299f3d | 2102 | } |
63d02d15 | 2103 | EXPORT_SYMBOL(inet_sk_rx_dst_set); |
5d299f3d | 2104 | |
3b401a81 | 2105 | const struct inet_connection_sock_af_ops ipv4_specific = { |
543d9cfe ACM |
2106 | .queue_xmit = ip_queue_xmit, |
2107 | .send_check = tcp_v4_send_check, | |
2108 | .rebuild_header = inet_sk_rebuild_header, | |
5d299f3d | 2109 | .sk_rx_dst_set = inet_sk_rx_dst_set, |
543d9cfe ACM |
2110 | .conn_request = tcp_v4_conn_request, |
2111 | .syn_recv_sock = tcp_v4_syn_recv_sock, | |
543d9cfe ACM |
2112 | .net_header_len = sizeof(struct iphdr), |
2113 | .setsockopt = ip_setsockopt, | |
2114 | .getsockopt = ip_getsockopt, | |
2115 | .addr2sockaddr = inet_csk_addr2sockaddr, | |
2116 | .sockaddr_len = sizeof(struct sockaddr_in), | |
3fdadf7d | 2117 | #ifdef CONFIG_COMPAT |
543d9cfe ACM |
2118 | .compat_setsockopt = compat_ip_setsockopt, |
2119 | .compat_getsockopt = compat_ip_getsockopt, | |
3fdadf7d | 2120 | #endif |
4fab9071 | 2121 | .mtu_reduced = tcp_v4_mtu_reduced, |
1da177e4 | 2122 | }; |
4bc2f18b | 2123 | EXPORT_SYMBOL(ipv4_specific); |
1da177e4 | 2124 | |
cfb6eeb4 | 2125 | #ifdef CONFIG_TCP_MD5SIG |
b2e4b3de | 2126 | static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = { |
cfb6eeb4 | 2127 | .md5_lookup = tcp_v4_md5_lookup, |
49a72dfb | 2128 | .calc_md5_hash = tcp_v4_md5_hash_skb, |
cfb6eeb4 | 2129 | .md5_parse = tcp_v4_parse_md5_keys, |
cfb6eeb4 | 2130 | }; |
b6332e6c | 2131 | #endif |
cfb6eeb4 | 2132 | |
1da177e4 LT |
2133 | /* NOTE: A lot of things set to zero explicitly by call to |
2134 | * sk_alloc() so need not be done here. | |
2135 | */ | |
2136 | static int tcp_v4_init_sock(struct sock *sk) | |
2137 | { | |
6687e988 | 2138 | struct inet_connection_sock *icsk = inet_csk(sk); |
1da177e4 | 2139 | |
900f65d3 | 2140 | tcp_init_sock(sk); |
1da177e4 | 2141 | |
8292a17a | 2142 | icsk->icsk_af_ops = &ipv4_specific; |
900f65d3 | 2143 | |
cfb6eeb4 | 2144 | #ifdef CONFIG_TCP_MD5SIG |
ac807fa8 | 2145 | tcp_sk(sk)->af_specific = &tcp_sock_ipv4_specific; |
cfb6eeb4 | 2146 | #endif |
1da177e4 | 2147 | |
1da177e4 LT |
2148 | return 0; |
2149 | } | |
2150 | ||
7d06b2e0 | 2151 | void tcp_v4_destroy_sock(struct sock *sk) |
1da177e4 LT |
2152 | { |
2153 | struct tcp_sock *tp = tcp_sk(sk); | |
2154 | ||
e1a4aa50 SL |
2155 | trace_tcp_destroy_sock(sk); |
2156 | ||
1da177e4 LT |
2157 | tcp_clear_xmit_timers(sk); |
2158 | ||
6687e988 | 2159 | tcp_cleanup_congestion_control(sk); |
317a76f9 | 2160 | |
734942cc DW |
2161 | tcp_cleanup_ulp(sk); |
2162 | ||
1da177e4 | 2163 | /* Cleanup up the write buffer. */ |
fe067e8a | 2164 | tcp_write_queue_purge(sk); |
1da177e4 | 2165 | |
cf1ef3f0 WW |
2166 | /* Check if we want to disable active TFO */ |
2167 | tcp_fastopen_active_disable_ofo_check(sk); | |
2168 | ||
1da177e4 | 2169 | /* Cleans up our, hopefully empty, out_of_order_queue. */ |
9f5afeae | 2170 | skb_rbtree_purge(&tp->out_of_order_queue); |
1da177e4 | 2171 | |
cfb6eeb4 YH |
2172 | #ifdef CONFIG_TCP_MD5SIG |
2173 | /* Clean up the MD5 key list, if any */ | |
2174 | if (tp->md5sig_info) { | |
a915da9b | 2175 | tcp_clear_md5_list(sk); |
fb7df5e4 | 2176 | kfree_rcu(rcu_dereference_protected(tp->md5sig_info, 1), rcu); |
cfb6eeb4 YH |
2177 | tp->md5sig_info = NULL; |
2178 | } | |
2179 | #endif | |
1a2449a8 | 2180 | |
1da177e4 | 2181 | /* Clean up a referenced TCP bind bucket. */ |
463c84b9 | 2182 | if (inet_csk(sk)->icsk_bind_hash) |
ab1e0a13 | 2183 | inet_put_port(sk); |
1da177e4 | 2184 | |
d983ea6f | 2185 | BUG_ON(rcu_access_pointer(tp->fastopen_rsk)); |
435cf559 | 2186 | |
cf60af03 YC |
2187 | /* If socket is aborted during connect operation */ |
2188 | tcp_free_fastopen_req(tp); | |
1fba70e5 | 2189 | tcp_fastopen_destroy_cipher(sk); |
cd8ae852 | 2190 | tcp_saved_syn_free(tp); |
cf60af03 | 2191 | |
180d8cd9 | 2192 | sk_sockets_allocated_dec(sk); |
1da177e4 | 2193 | } |
1da177e4 LT |
2194 | EXPORT_SYMBOL(tcp_v4_destroy_sock); |
2195 | ||
2196 | #ifdef CONFIG_PROC_FS | |
2197 | /* Proc filesystem TCP sock list dumping. */ | |
2198 | ||
a8b690f9 TH |
2199 | /* |
2200 | * Get next listener socket follow cur. If cur is NULL, get first socket | |
2201 | * starting from bucket given in st->bucket; when st->bucket is zero the | |
2202 | * very first socket in the hash table is returned. | |
2203 | */ | |
1da177e4 LT |
2204 | static void *listening_get_next(struct seq_file *seq, void *cur) |
2205 | { | |
37d849bb | 2206 | struct tcp_seq_afinfo *afinfo = PDE_DATA(file_inode(seq->file)); |
5799de0b | 2207 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2208 | struct net *net = seq_file_net(seq); |
3b24d854 | 2209 | struct inet_listen_hashbucket *ilb; |
8dbd76e7 | 2210 | struct hlist_nulls_node *node; |
3b24d854 | 2211 | struct sock *sk = cur; |
1da177e4 LT |
2212 | |
2213 | if (!sk) { | |
3b24d854 | 2214 | get_head: |
a8b690f9 | 2215 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
9652dc2e | 2216 | spin_lock(&ilb->lock); |
8dbd76e7 | 2217 | sk = sk_nulls_head(&ilb->nulls_head); |
a8b690f9 | 2218 | st->offset = 0; |
1da177e4 LT |
2219 | goto get_sk; |
2220 | } | |
5caea4ea | 2221 | ilb = &tcp_hashinfo.listening_hash[st->bucket]; |
1da177e4 | 2222 | ++st->num; |
a8b690f9 | 2223 | ++st->offset; |
1da177e4 | 2224 | |
8dbd76e7 | 2225 | sk = sk_nulls_next(sk); |
1da177e4 | 2226 | get_sk: |
8dbd76e7 | 2227 | sk_nulls_for_each_from(sk, node) { |
8475ef9f PE |
2228 | if (!net_eq(sock_net(sk), net)) |
2229 | continue; | |
37d849bb | 2230 | if (sk->sk_family == afinfo->family) |
3b24d854 | 2231 | return sk; |
1da177e4 | 2232 | } |
9652dc2e | 2233 | spin_unlock(&ilb->lock); |
a8b690f9 | 2234 | st->offset = 0; |
3b24d854 ED |
2235 | if (++st->bucket < INET_LHTABLE_SIZE) |
2236 | goto get_head; | |
2237 | return NULL; | |
1da177e4 LT |
2238 | } |
2239 | ||
2240 | static void *listening_get_idx(struct seq_file *seq, loff_t *pos) | |
2241 | { | |
a8b690f9 TH |
2242 | struct tcp_iter_state *st = seq->private; |
2243 | void *rc; | |
2244 | ||
2245 | st->bucket = 0; | |
2246 | st->offset = 0; | |
2247 | rc = listening_get_next(seq, NULL); | |
1da177e4 LT |
2248 | |
2249 | while (rc && *pos) { | |
2250 | rc = listening_get_next(seq, rc); | |
2251 | --*pos; | |
2252 | } | |
2253 | return rc; | |
2254 | } | |
2255 | ||
05dbc7b5 | 2256 | static inline bool empty_bucket(const struct tcp_iter_state *st) |
6eac5604 | 2257 | { |
05dbc7b5 | 2258 | return hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].chain); |
6eac5604 AK |
2259 | } |
2260 | ||
a8b690f9 TH |
2261 | /* |
2262 | * Get first established socket starting from bucket given in st->bucket. | |
2263 | * If st->bucket is zero, the very first socket in the hash is returned. | |
2264 | */ | |
1da177e4 LT |
2265 | static void *established_get_first(struct seq_file *seq) |
2266 | { | |
37d849bb | 2267 | struct tcp_seq_afinfo *afinfo = PDE_DATA(file_inode(seq->file)); |
5799de0b | 2268 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2269 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2270 | void *rc = NULL; |
2271 | ||
a8b690f9 TH |
2272 | st->offset = 0; |
2273 | for (; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) { | |
1da177e4 | 2274 | struct sock *sk; |
3ab5aee7 | 2275 | struct hlist_nulls_node *node; |
9db66bdc | 2276 | spinlock_t *lock = inet_ehash_lockp(&tcp_hashinfo, st->bucket); |
1da177e4 | 2277 | |
6eac5604 AK |
2278 | /* Lockless fast path for the common case of empty buckets */ |
2279 | if (empty_bucket(st)) | |
2280 | continue; | |
2281 | ||
9db66bdc | 2282 | spin_lock_bh(lock); |
3ab5aee7 | 2283 | sk_nulls_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) { |
37d849bb | 2284 | if (sk->sk_family != afinfo->family || |
878628fb | 2285 | !net_eq(sock_net(sk), net)) { |
1da177e4 LT |
2286 | continue; |
2287 | } | |
2288 | rc = sk; | |
2289 | goto out; | |
2290 | } | |
9db66bdc | 2291 | spin_unlock_bh(lock); |
1da177e4 LT |
2292 | } |
2293 | out: | |
2294 | return rc; | |
2295 | } | |
2296 | ||
2297 | static void *established_get_next(struct seq_file *seq, void *cur) | |
2298 | { | |
37d849bb | 2299 | struct tcp_seq_afinfo *afinfo = PDE_DATA(file_inode(seq->file)); |
1da177e4 | 2300 | struct sock *sk = cur; |
3ab5aee7 | 2301 | struct hlist_nulls_node *node; |
5799de0b | 2302 | struct tcp_iter_state *st = seq->private; |
a4146b1b | 2303 | struct net *net = seq_file_net(seq); |
1da177e4 LT |
2304 | |
2305 | ++st->num; | |
a8b690f9 | 2306 | ++st->offset; |
1da177e4 | 2307 | |
05dbc7b5 | 2308 | sk = sk_nulls_next(sk); |
1da177e4 | 2309 | |
3ab5aee7 | 2310 | sk_nulls_for_each_from(sk, node) { |
37d849bb CH |
2311 | if (sk->sk_family == afinfo->family && |
2312 | net_eq(sock_net(sk), net)) | |
05dbc7b5 | 2313 | return sk; |
1da177e4 LT |
2314 | } |
2315 | ||
05dbc7b5 ED |
2316 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
2317 | ++st->bucket; | |
2318 | return established_get_first(seq); | |
1da177e4 LT |
2319 | } |
2320 | ||
2321 | static void *established_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 | rc = established_get_first(seq); | |
1da177e4 LT |
2328 | |
2329 | while (rc && pos) { | |
2330 | rc = established_get_next(seq, rc); | |
2331 | --pos; | |
7174259e | 2332 | } |
1da177e4 LT |
2333 | return rc; |
2334 | } | |
2335 | ||
2336 | static void *tcp_get_idx(struct seq_file *seq, loff_t pos) | |
2337 | { | |
2338 | void *rc; | |
5799de0b | 2339 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2340 | |
1da177e4 LT |
2341 | st->state = TCP_SEQ_STATE_LISTENING; |
2342 | rc = listening_get_idx(seq, &pos); | |
2343 | ||
2344 | if (!rc) { | |
1da177e4 LT |
2345 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
2346 | rc = established_get_idx(seq, pos); | |
2347 | } | |
2348 | ||
2349 | return rc; | |
2350 | } | |
2351 | ||
a8b690f9 TH |
2352 | static void *tcp_seek_last_pos(struct seq_file *seq) |
2353 | { | |
2354 | struct tcp_iter_state *st = seq->private; | |
2355 | int offset = st->offset; | |
2356 | int orig_num = st->num; | |
2357 | void *rc = NULL; | |
2358 | ||
2359 | switch (st->state) { | |
a8b690f9 TH |
2360 | case TCP_SEQ_STATE_LISTENING: |
2361 | if (st->bucket >= INET_LHTABLE_SIZE) | |
2362 | break; | |
2363 | st->state = TCP_SEQ_STATE_LISTENING; | |
2364 | rc = listening_get_next(seq, NULL); | |
2365 | while (offset-- && rc) | |
2366 | rc = listening_get_next(seq, rc); | |
2367 | if (rc) | |
2368 | break; | |
2369 | st->bucket = 0; | |
05dbc7b5 | 2370 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
a8eceea8 | 2371 | fallthrough; |
a8b690f9 | 2372 | case TCP_SEQ_STATE_ESTABLISHED: |
a8b690f9 TH |
2373 | if (st->bucket > tcp_hashinfo.ehash_mask) |
2374 | break; | |
2375 | rc = established_get_first(seq); | |
2376 | while (offset-- && rc) | |
2377 | rc = established_get_next(seq, rc); | |
2378 | } | |
2379 | ||
2380 | st->num = orig_num; | |
2381 | ||
2382 | return rc; | |
2383 | } | |
2384 | ||
37d849bb | 2385 | void *tcp_seq_start(struct seq_file *seq, loff_t *pos) |
1da177e4 | 2386 | { |
5799de0b | 2387 | struct tcp_iter_state *st = seq->private; |
a8b690f9 TH |
2388 | void *rc; |
2389 | ||
2390 | if (*pos && *pos == st->last_pos) { | |
2391 | rc = tcp_seek_last_pos(seq); | |
2392 | if (rc) | |
2393 | goto out; | |
2394 | } | |
2395 | ||
1da177e4 LT |
2396 | st->state = TCP_SEQ_STATE_LISTENING; |
2397 | st->num = 0; | |
a8b690f9 TH |
2398 | st->bucket = 0; |
2399 | st->offset = 0; | |
2400 | rc = *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
2401 | ||
2402 | out: | |
2403 | st->last_pos = *pos; | |
2404 | return rc; | |
1da177e4 | 2405 | } |
37d849bb | 2406 | EXPORT_SYMBOL(tcp_seq_start); |
1da177e4 | 2407 | |
37d849bb | 2408 | void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
1da177e4 | 2409 | { |
a8b690f9 | 2410 | struct tcp_iter_state *st = seq->private; |
1da177e4 | 2411 | void *rc = NULL; |
1da177e4 LT |
2412 | |
2413 | if (v == SEQ_START_TOKEN) { | |
2414 | rc = tcp_get_idx(seq, 0); | |
2415 | goto out; | |
2416 | } | |
1da177e4 LT |
2417 | |
2418 | switch (st->state) { | |
1da177e4 LT |
2419 | case TCP_SEQ_STATE_LISTENING: |
2420 | rc = listening_get_next(seq, v); | |
2421 | if (!rc) { | |
1da177e4 | 2422 | st->state = TCP_SEQ_STATE_ESTABLISHED; |
a8b690f9 TH |
2423 | st->bucket = 0; |
2424 | st->offset = 0; | |
1da177e4 LT |
2425 | rc = established_get_first(seq); |
2426 | } | |
2427 | break; | |
2428 | case TCP_SEQ_STATE_ESTABLISHED: | |
1da177e4 LT |
2429 | rc = established_get_next(seq, v); |
2430 | break; | |
2431 | } | |
2432 | out: | |
2433 | ++*pos; | |
a8b690f9 | 2434 | st->last_pos = *pos; |
1da177e4 LT |
2435 | return rc; |
2436 | } | |
37d849bb | 2437 | EXPORT_SYMBOL(tcp_seq_next); |
1da177e4 | 2438 | |
37d849bb | 2439 | void tcp_seq_stop(struct seq_file *seq, void *v) |
1da177e4 | 2440 | { |
5799de0b | 2441 | struct tcp_iter_state *st = seq->private; |
1da177e4 LT |
2442 | |
2443 | switch (st->state) { | |
1da177e4 LT |
2444 | case TCP_SEQ_STATE_LISTENING: |
2445 | if (v != SEQ_START_TOKEN) | |
9652dc2e | 2446 | spin_unlock(&tcp_hashinfo.listening_hash[st->bucket].lock); |
1da177e4 | 2447 | break; |
1da177e4 LT |
2448 | case TCP_SEQ_STATE_ESTABLISHED: |
2449 | if (v) | |
9db66bdc | 2450 | spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket)); |
1da177e4 LT |
2451 | break; |
2452 | } | |
2453 | } | |
37d849bb | 2454 | EXPORT_SYMBOL(tcp_seq_stop); |
1da177e4 | 2455 | |
d4f06873 | 2456 | static void get_openreq4(const struct request_sock *req, |
aa3a0c8c | 2457 | struct seq_file *f, int i) |
1da177e4 | 2458 | { |
2e6599cb | 2459 | const struct inet_request_sock *ireq = inet_rsk(req); |
fa76ce73 | 2460 | long delta = req->rsk_timer.expires - jiffies; |
1da177e4 | 2461 | |
5e659e4c | 2462 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
652586df | 2463 | " %02X %08X:%08X %02X:%08lX %08X %5u %8d %u %d %pK", |
1da177e4 | 2464 | i, |
634fb979 | 2465 | ireq->ir_loc_addr, |
d4f06873 | 2466 | ireq->ir_num, |
634fb979 ED |
2467 | ireq->ir_rmt_addr, |
2468 | ntohs(ireq->ir_rmt_port), | |
1da177e4 LT |
2469 | TCP_SYN_RECV, |
2470 | 0, 0, /* could print option size, but that is af dependent. */ | |
2471 | 1, /* timers active (only the expire timer) */ | |
a399a805 | 2472 | jiffies_delta_to_clock_t(delta), |
e6c022a4 | 2473 | req->num_timeout, |
aa3a0c8c ED |
2474 | from_kuid_munged(seq_user_ns(f), |
2475 | sock_i_uid(req->rsk_listener)), | |
1da177e4 LT |
2476 | 0, /* non standard timer */ |
2477 | 0, /* open_requests have no inode */ | |
d4f06873 | 2478 | 0, |
652586df | 2479 | req); |
1da177e4 LT |
2480 | } |
2481 | ||
652586df | 2482 | static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i) |
1da177e4 LT |
2483 | { |
2484 | int timer_active; | |
2485 | unsigned long timer_expires; | |
cf533ea5 | 2486 | const struct tcp_sock *tp = tcp_sk(sk); |
cf4c6bf8 | 2487 | const struct inet_connection_sock *icsk = inet_csk(sk); |
cf533ea5 | 2488 | const struct inet_sock *inet = inet_sk(sk); |
0536fcc0 | 2489 | const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq; |
c720c7e8 ED |
2490 | __be32 dest = inet->inet_daddr; |
2491 | __be32 src = inet->inet_rcv_saddr; | |
2492 | __u16 destp = ntohs(inet->inet_dport); | |
2493 | __u16 srcp = ntohs(inet->inet_sport); | |
49d09007 | 2494 | int rx_queue; |
00fd38d9 | 2495 | int state; |
1da177e4 | 2496 | |
6ba8a3b1 | 2497 | if (icsk->icsk_pending == ICSK_TIME_RETRANS || |
57dde7f7 | 2498 | icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || |
6ba8a3b1 | 2499 | icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { |
1da177e4 | 2500 | timer_active = 1; |
463c84b9 ACM |
2501 | timer_expires = icsk->icsk_timeout; |
2502 | } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { | |
1da177e4 | 2503 | timer_active = 4; |
463c84b9 | 2504 | timer_expires = icsk->icsk_timeout; |
cf4c6bf8 | 2505 | } else if (timer_pending(&sk->sk_timer)) { |
1da177e4 | 2506 | timer_active = 2; |
cf4c6bf8 | 2507 | timer_expires = sk->sk_timer.expires; |
1da177e4 LT |
2508 | } else { |
2509 | timer_active = 0; | |
2510 | timer_expires = jiffies; | |
2511 | } | |
2512 | ||
986ffdfd | 2513 | state = inet_sk_state_load(sk); |
00fd38d9 | 2514 | if (state == TCP_LISTEN) |
288efe86 | 2515 | rx_queue = READ_ONCE(sk->sk_ack_backlog); |
49d09007 | 2516 | else |
00fd38d9 ED |
2517 | /* Because we don't lock the socket, |
2518 | * we might find a transient negative value. | |
49d09007 | 2519 | */ |
dba7d9b8 | 2520 | rx_queue = max_t(int, READ_ONCE(tp->rcv_nxt) - |
7db48e98 | 2521 | READ_ONCE(tp->copied_seq), 0); |
49d09007 | 2522 | |
5e659e4c | 2523 | seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX " |
652586df | 2524 | "%08X %5u %8d %lu %d %pK %lu %lu %u %u %d", |
00fd38d9 | 2525 | i, src, srcp, dest, destp, state, |
0f317464 | 2526 | READ_ONCE(tp->write_seq) - tp->snd_una, |
49d09007 | 2527 | rx_queue, |
1da177e4 | 2528 | timer_active, |
a399a805 | 2529 | jiffies_delta_to_clock_t(timer_expires - jiffies), |
463c84b9 | 2530 | icsk->icsk_retransmits, |
a7cb5a49 | 2531 | from_kuid_munged(seq_user_ns(f), sock_i_uid(sk)), |
6687e988 | 2532 | icsk->icsk_probes_out, |
cf4c6bf8 | 2533 | sock_i_ino(sk), |
41c6d650 | 2534 | refcount_read(&sk->sk_refcnt), sk, |
7be87351 SH |
2535 | jiffies_to_clock_t(icsk->icsk_rto), |
2536 | jiffies_to_clock_t(icsk->icsk_ack.ato), | |
31954cd8 | 2537 | (icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(sk), |
1da177e4 | 2538 | tp->snd_cwnd, |
00fd38d9 ED |
2539 | state == TCP_LISTEN ? |
2540 | fastopenq->max_qlen : | |
652586df | 2541 | (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh)); |
1da177e4 LT |
2542 | } |
2543 | ||
cf533ea5 | 2544 | static void get_timewait4_sock(const struct inet_timewait_sock *tw, |
652586df | 2545 | struct seq_file *f, int i) |
1da177e4 | 2546 | { |
789f558c | 2547 | long delta = tw->tw_timer.expires - jiffies; |
23f33c2d | 2548 | __be32 dest, src; |
1da177e4 | 2549 | __u16 destp, srcp; |
1da177e4 LT |
2550 | |
2551 | dest = tw->tw_daddr; | |
2552 | src = tw->tw_rcv_saddr; | |
2553 | destp = ntohs(tw->tw_dport); | |
2554 | srcp = ntohs(tw->tw_sport); | |
2555 | ||
5e659e4c | 2556 | seq_printf(f, "%4d: %08X:%04X %08X:%04X" |
652586df | 2557 | " %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK", |
1da177e4 | 2558 | i, src, srcp, dest, destp, tw->tw_substate, 0, 0, |
a399a805 | 2559 | 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, |
41c6d650 | 2560 | refcount_read(&tw->tw_refcnt), tw); |
1da177e4 LT |
2561 | } |
2562 | ||
2563 | #define TMPSZ 150 | |
2564 | ||
2565 | static int tcp4_seq_show(struct seq_file *seq, void *v) | |
2566 | { | |
5799de0b | 2567 | struct tcp_iter_state *st; |
05dbc7b5 | 2568 | struct sock *sk = v; |
1da177e4 | 2569 | |
652586df | 2570 | seq_setwidth(seq, TMPSZ - 1); |
1da177e4 | 2571 | if (v == SEQ_START_TOKEN) { |
652586df | 2572 | seq_puts(seq, " sl local_address rem_address st tx_queue " |
1da177e4 LT |
2573 | "rx_queue tr tm->when retrnsmt uid timeout " |
2574 | "inode"); | |
2575 | goto out; | |
2576 | } | |
2577 | st = seq->private; | |
2578 | ||
079096f1 ED |
2579 | if (sk->sk_state == TCP_TIME_WAIT) |
2580 | get_timewait4_sock(v, seq, st->num); | |
2581 | else if (sk->sk_state == TCP_NEW_SYN_RECV) | |
aa3a0c8c | 2582 | get_openreq4(v, seq, st->num); |
079096f1 ED |
2583 | else |
2584 | get_tcp4_sock(v, seq, st->num); | |
1da177e4 | 2585 | out: |
652586df | 2586 | seq_pad(seq, '\n'); |
1da177e4 LT |
2587 | return 0; |
2588 | } | |
2589 | ||
37d849bb CH |
2590 | static const struct seq_operations tcp4_seq_ops = { |
2591 | .show = tcp4_seq_show, | |
2592 | .start = tcp_seq_start, | |
2593 | .next = tcp_seq_next, | |
2594 | .stop = tcp_seq_stop, | |
2595 | }; | |
2596 | ||
1da177e4 | 2597 | static struct tcp_seq_afinfo tcp4_seq_afinfo = { |
1da177e4 | 2598 | .family = AF_INET, |
1da177e4 LT |
2599 | }; |
2600 | ||
2c8c1e72 | 2601 | static int __net_init tcp4_proc_init_net(struct net *net) |
757764f6 | 2602 | { |
c3506372 CH |
2603 | if (!proc_create_net_data("tcp", 0444, net->proc_net, &tcp4_seq_ops, |
2604 | sizeof(struct tcp_iter_state), &tcp4_seq_afinfo)) | |
37d849bb CH |
2605 | return -ENOMEM; |
2606 | return 0; | |
757764f6 PE |
2607 | } |
2608 | ||
2c8c1e72 | 2609 | static void __net_exit tcp4_proc_exit_net(struct net *net) |
757764f6 | 2610 | { |
37d849bb | 2611 | remove_proc_entry("tcp", net->proc_net); |
757764f6 PE |
2612 | } |
2613 | ||
2614 | static struct pernet_operations tcp4_net_ops = { | |
2615 | .init = tcp4_proc_init_net, | |
2616 | .exit = tcp4_proc_exit_net, | |
2617 | }; | |
2618 | ||
1da177e4 LT |
2619 | int __init tcp4_proc_init(void) |
2620 | { | |
757764f6 | 2621 | return register_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2622 | } |
2623 | ||
2624 | void tcp4_proc_exit(void) | |
2625 | { | |
757764f6 | 2626 | unregister_pernet_subsys(&tcp4_net_ops); |
1da177e4 LT |
2627 | } |
2628 | #endif /* CONFIG_PROC_FS */ | |
2629 | ||
2630 | struct proto tcp_prot = { | |
2631 | .name = "TCP", | |
2632 | .owner = THIS_MODULE, | |
2633 | .close = tcp_close, | |
d74bad4e | 2634 | .pre_connect = tcp_v4_pre_connect, |
1da177e4 LT |
2635 | .connect = tcp_v4_connect, |
2636 | .disconnect = tcp_disconnect, | |
463c84b9 | 2637 | .accept = inet_csk_accept, |
1da177e4 LT |
2638 | .ioctl = tcp_ioctl, |
2639 | .init = tcp_v4_init_sock, | |
2640 | .destroy = tcp_v4_destroy_sock, | |
2641 | .shutdown = tcp_shutdown, | |
2642 | .setsockopt = tcp_setsockopt, | |
2643 | .getsockopt = tcp_getsockopt, | |
4b9d07a4 | 2644 | .keepalive = tcp_set_keepalive, |
1da177e4 | 2645 | .recvmsg = tcp_recvmsg, |
7ba42910 CG |
2646 | .sendmsg = tcp_sendmsg, |
2647 | .sendpage = tcp_sendpage, | |
1da177e4 | 2648 | .backlog_rcv = tcp_v4_do_rcv, |
46d3ceab | 2649 | .release_cb = tcp_release_cb, |
ab1e0a13 ACM |
2650 | .hash = inet_hash, |
2651 | .unhash = inet_unhash, | |
2652 | .get_port = inet_csk_get_port, | |
1da177e4 | 2653 | .enter_memory_pressure = tcp_enter_memory_pressure, |
06044751 | 2654 | .leave_memory_pressure = tcp_leave_memory_pressure, |
c9bee3b7 | 2655 | .stream_memory_free = tcp_stream_memory_free, |
1da177e4 | 2656 | .sockets_allocated = &tcp_sockets_allocated, |
0a5578cf | 2657 | .orphan_count = &tcp_orphan_count, |
1da177e4 LT |
2658 | .memory_allocated = &tcp_memory_allocated, |
2659 | .memory_pressure = &tcp_memory_pressure, | |
a4fe34bf | 2660 | .sysctl_mem = sysctl_tcp_mem, |
356d1833 ED |
2661 | .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_tcp_wmem), |
2662 | .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_tcp_rmem), | |
1da177e4 LT |
2663 | .max_header = MAX_TCP_HEADER, |
2664 | .obj_size = sizeof(struct tcp_sock), | |
5f0d5a3a | 2665 | .slab_flags = SLAB_TYPESAFE_BY_RCU, |
6d6ee43e | 2666 | .twsk_prot = &tcp_timewait_sock_ops, |
60236fdd | 2667 | .rsk_prot = &tcp_request_sock_ops, |
39d8cda7 | 2668 | .h.hashinfo = &tcp_hashinfo, |
7ba42910 | 2669 | .no_autobind = true, |
543d9cfe ACM |
2670 | #ifdef CONFIG_COMPAT |
2671 | .compat_setsockopt = compat_tcp_setsockopt, | |
2672 | .compat_getsockopt = compat_tcp_getsockopt, | |
d1a4c0b3 | 2673 | #endif |
c1e64e29 | 2674 | .diag_destroy = tcp_abort, |
1da177e4 | 2675 | }; |
4bc2f18b | 2676 | EXPORT_SYMBOL(tcp_prot); |
1da177e4 | 2677 | |
bdbbb852 ED |
2678 | static void __net_exit tcp_sk_exit(struct net *net) |
2679 | { | |
2680 | int cpu; | |
2681 | ||
b506bc97 | 2682 | if (net->ipv4.tcp_congestion_control) |
0baf26b0 MKL |
2683 | bpf_module_put(net->ipv4.tcp_congestion_control, |
2684 | net->ipv4.tcp_congestion_control->owner); | |
6670e152 | 2685 | |
bdbbb852 ED |
2686 | for_each_possible_cpu(cpu) |
2687 | inet_ctl_sock_destroy(*per_cpu_ptr(net->ipv4.tcp_sk, cpu)); | |
2688 | free_percpu(net->ipv4.tcp_sk); | |
2689 | } | |
2690 | ||
046ee902 DL |
2691 | static int __net_init tcp_sk_init(struct net *net) |
2692 | { | |
fee83d09 | 2693 | int res, cpu, cnt; |
bdbbb852 ED |
2694 | |
2695 | net->ipv4.tcp_sk = alloc_percpu(struct sock *); | |
2696 | if (!net->ipv4.tcp_sk) | |
2697 | return -ENOMEM; | |
2698 | ||
2699 | for_each_possible_cpu(cpu) { | |
2700 | struct sock *sk; | |
2701 | ||
2702 | res = inet_ctl_sock_create(&sk, PF_INET, SOCK_RAW, | |
2703 | IPPROTO_TCP, net); | |
2704 | if (res) | |
2705 | goto fail; | |
a9d6532b | 2706 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); |
431280ee ED |
2707 | |
2708 | /* Please enforce IP_DF and IPID==0 for RST and | |
2709 | * ACK sent in SYN-RECV and TIME-WAIT state. | |
2710 | */ | |
2711 | inet_sk(sk)->pmtudisc = IP_PMTUDISC_DO; | |
2712 | ||
bdbbb852 ED |
2713 | *per_cpu_ptr(net->ipv4.tcp_sk, cpu) = sk; |
2714 | } | |
49213555 | 2715 | |
5d134f1c | 2716 | net->ipv4.sysctl_tcp_ecn = 2; |
49213555 DB |
2717 | net->ipv4.sysctl_tcp_ecn_fallback = 1; |
2718 | ||
b0f9ca53 | 2719 | net->ipv4.sysctl_tcp_base_mss = TCP_BASE_MSS; |
5f3e2bf0 | 2720 | net->ipv4.sysctl_tcp_min_snd_mss = TCP_MIN_SND_MSS; |
6b58e0a5 | 2721 | net->ipv4.sysctl_tcp_probe_threshold = TCP_PROBE_THRESHOLD; |
05cbc0db | 2722 | net->ipv4.sysctl_tcp_probe_interval = TCP_PROBE_INTERVAL; |
c04b79b6 | 2723 | net->ipv4.sysctl_tcp_mtu_probe_floor = TCP_MIN_SND_MSS; |
046ee902 | 2724 | |
13b287e8 | 2725 | net->ipv4.sysctl_tcp_keepalive_time = TCP_KEEPALIVE_TIME; |
9bd6861b | 2726 | net->ipv4.sysctl_tcp_keepalive_probes = TCP_KEEPALIVE_PROBES; |
b840d15d | 2727 | net->ipv4.sysctl_tcp_keepalive_intvl = TCP_KEEPALIVE_INTVL; |
13b287e8 | 2728 | |
6fa25166 | 2729 | net->ipv4.sysctl_tcp_syn_retries = TCP_SYN_RETRIES; |
7c083ecb | 2730 | net->ipv4.sysctl_tcp_synack_retries = TCP_SYNACK_RETRIES; |
0aca737d | 2731 | net->ipv4.sysctl_tcp_syncookies = 1; |
1043e25f | 2732 | net->ipv4.sysctl_tcp_reordering = TCP_FASTRETRANS_THRESH; |
ae5c3f40 | 2733 | net->ipv4.sysctl_tcp_retries1 = TCP_RETR1; |
c6214a97 | 2734 | net->ipv4.sysctl_tcp_retries2 = TCP_RETR2; |
c402d9be | 2735 | net->ipv4.sysctl_tcp_orphan_retries = 0; |
1e579caa | 2736 | net->ipv4.sysctl_tcp_fin_timeout = TCP_FIN_TIMEOUT; |
4979f2d9 | 2737 | net->ipv4.sysctl_tcp_notsent_lowat = UINT_MAX; |
79e9fed4 | 2738 | net->ipv4.sysctl_tcp_tw_reuse = 2; |
65e6d901 | 2739 | net->ipv4.sysctl_tcp_no_ssthresh_metrics_save = 1; |
12ed8244 | 2740 | |
fee83d09 | 2741 | cnt = tcp_hashinfo.ehash_mask + 1; |
743e4815 | 2742 | net->ipv4.tcp_death_row.sysctl_max_tw_buckets = cnt / 2; |
1946e672 HY |
2743 | net->ipv4.tcp_death_row.hashinfo = &tcp_hashinfo; |
2744 | ||
623d0c2d | 2745 | net->ipv4.sysctl_max_syn_backlog = max(128, cnt / 128); |
f9301034 | 2746 | net->ipv4.sysctl_tcp_sack = 1; |
9bb37ef0 | 2747 | net->ipv4.sysctl_tcp_window_scaling = 1; |
5d2ed052 | 2748 | net->ipv4.sysctl_tcp_timestamps = 1; |
2ae21cf5 | 2749 | net->ipv4.sysctl_tcp_early_retrans = 3; |
e20223f1 | 2750 | net->ipv4.sysctl_tcp_recovery = TCP_RACK_LOSS_DETECTION; |
b510f0d2 | 2751 | net->ipv4.sysctl_tcp_slow_start_after_idle = 1; /* By default, RFC2861 behavior. */ |
e0a1e5b5 | 2752 | net->ipv4.sysctl_tcp_retrans_collapse = 1; |
c6e21803 | 2753 | net->ipv4.sysctl_tcp_max_reordering = 300; |
6496f6bd | 2754 | net->ipv4.sysctl_tcp_dsack = 1; |
0c12654a | 2755 | net->ipv4.sysctl_tcp_app_win = 31; |
94f0893e | 2756 | net->ipv4.sysctl_tcp_adv_win_scale = 1; |
af9b69a7 | 2757 | net->ipv4.sysctl_tcp_frto = 2; |
4540c0cf | 2758 | net->ipv4.sysctl_tcp_moderate_rcvbuf = 1; |
d06a9904 ED |
2759 | /* This limits the percentage of the congestion window which we |
2760 | * will allow a single TSO frame to consume. Building TSO frames | |
2761 | * which are too large can cause TCP streams to be bursty. | |
2762 | */ | |
2763 | net->ipv4.sysctl_tcp_tso_win_divisor = 3; | |
c73e5807 ED |
2764 | /* Default TSQ limit of 16 TSO segments */ |
2765 | net->ipv4.sysctl_tcp_limit_output_bytes = 16 * 65536; | |
b530b681 ED |
2766 | /* rfc5961 challenge ack rate limiting */ |
2767 | net->ipv4.sysctl_tcp_challenge_ack_limit = 1000; | |
26e9596e | 2768 | net->ipv4.sysctl_tcp_min_tso_segs = 2; |
bd239704 | 2769 | net->ipv4.sysctl_tcp_min_rtt_wlen = 300; |
790f00e1 | 2770 | net->ipv4.sysctl_tcp_autocorking = 1; |
4170ba6b | 2771 | net->ipv4.sysctl_tcp_invalid_ratelimit = HZ/2; |
23a7102a | 2772 | net->ipv4.sysctl_tcp_pacing_ss_ratio = 200; |
c26e91f8 | 2773 | net->ipv4.sysctl_tcp_pacing_ca_ratio = 120; |
356d1833 ED |
2774 | if (net != &init_net) { |
2775 | memcpy(net->ipv4.sysctl_tcp_rmem, | |
2776 | init_net.ipv4.sysctl_tcp_rmem, | |
2777 | sizeof(init_net.ipv4.sysctl_tcp_rmem)); | |
2778 | memcpy(net->ipv4.sysctl_tcp_wmem, | |
2779 | init_net.ipv4.sysctl_tcp_wmem, | |
2780 | sizeof(init_net.ipv4.sysctl_tcp_wmem)); | |
2781 | } | |
6d82aa24 | 2782 | net->ipv4.sysctl_tcp_comp_sack_delay_ns = NSEC_PER_MSEC; |
9c21d2fc | 2783 | net->ipv4.sysctl_tcp_comp_sack_nr = 44; |
e1cfcbe8 | 2784 | net->ipv4.sysctl_tcp_fastopen = TFO_CLIENT_ENABLE; |
43713848 | 2785 | spin_lock_init(&net->ipv4.tcp_fastopen_ctx_lock); |
3733be14 HY |
2786 | net->ipv4.sysctl_tcp_fastopen_blackhole_timeout = 60 * 60; |
2787 | atomic_set(&net->ipv4.tfo_active_disable_times, 0); | |
e1cfcbe8 | 2788 | |
6670e152 SH |
2789 | /* Reno is always built in */ |
2790 | if (!net_eq(net, &init_net) && | |
0baf26b0 MKL |
2791 | bpf_try_module_get(init_net.ipv4.tcp_congestion_control, |
2792 | init_net.ipv4.tcp_congestion_control->owner)) | |
6670e152 SH |
2793 | net->ipv4.tcp_congestion_control = init_net.ipv4.tcp_congestion_control; |
2794 | else | |
2795 | net->ipv4.tcp_congestion_control = &tcp_reno; | |
2796 | ||
49213555 | 2797 | return 0; |
bdbbb852 ED |
2798 | fail: |
2799 | tcp_sk_exit(net); | |
2800 | ||
2801 | return res; | |
b099ce26 EB |
2802 | } |
2803 | ||
2804 | static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list) | |
2805 | { | |
43713848 HY |
2806 | struct net *net; |
2807 | ||
1946e672 | 2808 | inet_twsk_purge(&tcp_hashinfo, AF_INET); |
43713848 HY |
2809 | |
2810 | list_for_each_entry(net, net_exit_list, exit_list) | |
2811 | tcp_fastopen_ctx_destroy(net); | |
046ee902 DL |
2812 | } |
2813 | ||
2814 | static struct pernet_operations __net_initdata tcp_sk_ops = { | |
b099ce26 EB |
2815 | .init = tcp_sk_init, |
2816 | .exit = tcp_sk_exit, | |
2817 | .exit_batch = tcp_sk_exit_batch, | |
046ee902 DL |
2818 | }; |
2819 | ||
9b0f976f | 2820 | void __init tcp_v4_init(void) |
1da177e4 | 2821 | { |
6a1b3054 | 2822 | if (register_pernet_subsys(&tcp_sk_ops)) |
1da177e4 | 2823 | panic("Failed to create the TCP control socket.\n"); |
1da177e4 | 2824 | } |