Commit | Line | Data |
---|---|---|
2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
7c657876 ACM |
2 | /* |
3 | * net/dccp/ipv4.c | |
4 | * | |
5 | * An implementation of the DCCP protocol | |
6 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br> | |
7c657876 ACM |
7 | */ |
8 | ||
7c657876 ACM |
9 | #include <linux/dccp.h> |
10 | #include <linux/icmp.h> | |
5a0e3ad6 | 11 | #include <linux/slab.h> |
7c657876 ACM |
12 | #include <linux/module.h> |
13 | #include <linux/skbuff.h> | |
14 | #include <linux/random.h> | |
15 | ||
16 | #include <net/icmp.h> | |
b61fafc4 | 17 | #include <net/inet_common.h> |
7c657876 | 18 | #include <net/inet_hashtables.h> |
14c85021 | 19 | #include <net/inet_sock.h> |
b61fafc4 | 20 | #include <net/protocol.h> |
7c657876 | 21 | #include <net/sock.h> |
6d6ee43e | 22 | #include <net/timewait_sock.h> |
7c657876 ACM |
23 | #include <net/tcp_states.h> |
24 | #include <net/xfrm.h> | |
6e5714ea | 25 | #include <net/secure_seq.h> |
b98b3304 | 26 | #include <net/netns/generic.h> |
7c657876 | 27 | |
ae31c339 | 28 | #include "ackvec.h" |
7c657876 ACM |
29 | #include "ccid.h" |
30 | #include "dccp.h" | |
afe00251 | 31 | #include "feat.h" |
7c657876 | 32 | |
b98b3304 FW |
33 | struct dccp_v4_pernet { |
34 | struct sock *v4_ctl_sk; | |
35 | }; | |
36 | ||
37 | static unsigned int dccp_v4_pernet_id __read_mostly; | |
38 | ||
72478873 | 39 | /* |
b98b3304 | 40 | * The per-net v4_ctl_sk socket is used for responding to |
72478873 ACM |
41 | * the Out-of-the-blue (OOTB) packets. A control sock will be created |
42 | * for this socket at the initialization time. | |
43 | */ | |
72478873 | 44 | |
f21e68ca | 45 | int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) |
7c657876 | 46 | { |
2d7192d6 | 47 | const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
7c657876 ACM |
48 | struct inet_sock *inet = inet_sk(sk); |
49 | struct dccp_sock *dp = dccp_sk(sk); | |
dca8b089 | 50 | __be16 orig_sport, orig_dport; |
8c5dae4c | 51 | __be32 daddr, nexthop; |
2c42758c | 52 | struct flowi4 *fl4; |
2d7192d6 | 53 | struct rtable *rt; |
7c657876 | 54 | int err; |
f6d8bd05 | 55 | struct ip_options_rcu *inet_opt; |
7c657876 ACM |
56 | |
57 | dp->dccps_role = DCCP_ROLE_CLIENT; | |
58 | ||
59 | if (addr_len < sizeof(struct sockaddr_in)) | |
60 | return -EINVAL; | |
61 | ||
62 | if (usin->sin_family != AF_INET) | |
63 | return -EAFNOSUPPORT; | |
64 | ||
65 | nexthop = daddr = usin->sin_addr.s_addr; | |
f6d8bd05 ED |
66 | |
67 | inet_opt = rcu_dereference_protected(inet->inet_opt, | |
1e1d04e6 | 68 | lockdep_sock_is_held(sk)); |
f6d8bd05 | 69 | if (inet_opt != NULL && inet_opt->opt.srr) { |
7c657876 ACM |
70 | if (daddr == 0) |
71 | return -EINVAL; | |
f6d8bd05 | 72 | nexthop = inet_opt->opt.faddr; |
7c657876 ACM |
73 | } |
74 | ||
dca8b089 DM |
75 | orig_sport = inet->inet_sport; |
76 | orig_dport = usin->sin_port; | |
2c42758c DM |
77 | fl4 = &inet->cork.fl.u.ip4; |
78 | rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, | |
67e1e2f4 GN |
79 | sk->sk_bound_dev_if, IPPROTO_DCCP, orig_sport, |
80 | orig_dport, sk); | |
b23dd4fe DM |
81 | if (IS_ERR(rt)) |
82 | return PTR_ERR(rt); | |
7c657876 ACM |
83 | |
84 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { | |
85 | ip_rt_put(rt); | |
86 | return -ENETUNREACH; | |
87 | } | |
88 | ||
f6d8bd05 | 89 | if (inet_opt == NULL || !inet_opt->opt.srr) |
2c42758c | 90 | daddr = fl4->daddr; |
7c657876 | 91 | |
28044fc1 | 92 | if (inet->inet_saddr == 0) { |
8c5dae4c | 93 | err = inet_bhash2_update_saddr(sk, &fl4->saddr, AF_INET); |
28044fc1 | 94 | if (err) { |
28044fc1 JK |
95 | ip_rt_put(rt); |
96 | return err; | |
97 | } | |
8c5dae4c KI |
98 | } else { |
99 | sk_rcv_saddr_set(sk, inet->inet_saddr); | |
28044fc1 JK |
100 | } |
101 | ||
c720c7e8 | 102 | inet->inet_dport = usin->sin_port; |
d1e559d0 | 103 | sk_daddr_set(sk, daddr); |
7c657876 | 104 | |
d83d8461 | 105 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
f6d8bd05 ED |
106 | if (inet_opt) |
107 | inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; | |
7c657876 ACM |
108 | /* |
109 | * Socket identity is still unknown (sport may be zero). | |
110 | * However we set state to DCCP_REQUESTING and not releasing socket | |
111 | * lock select source port, enter ourselves into the hash tables and | |
112 | * complete initialization after this. | |
113 | */ | |
114 | dccp_set_state(sk, DCCP_REQUESTING); | |
a7f5e7f1 | 115 | err = inet_hash_connect(&dccp_death_row, sk); |
7c657876 ACM |
116 | if (err != 0) |
117 | goto failure; | |
118 | ||
2c42758c | 119 | rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, |
b23dd4fe DM |
120 | inet->inet_sport, inet->inet_dport, sk); |
121 | if (IS_ERR(rt)) { | |
525c6465 | 122 | err = PTR_ERR(rt); |
b23dd4fe | 123 | rt = NULL; |
7c657876 | 124 | goto failure; |
b23dd4fe | 125 | } |
7c657876 | 126 | /* OK, now commit destination to socket. */ |
d8d1f30b | 127 | sk_setup_caps(sk, &rt->dst); |
7c657876 | 128 | |
c720c7e8 ED |
129 | dp->dccps_iss = secure_dccp_sequence_number(inet->inet_saddr, |
130 | inet->inet_daddr, | |
131 | inet->inet_sport, | |
132 | inet->inet_dport); | |
f866fbc8 | 133 | atomic_set(&inet->inet_id, get_random_u16()); |
7c657876 ACM |
134 | |
135 | err = dccp_connect(sk); | |
136 | rt = NULL; | |
137 | if (err != 0) | |
138 | goto failure; | |
139 | out: | |
140 | return err; | |
141 | failure: | |
7690af3f ACM |
142 | /* |
143 | * This unhashes the socket and releases the local port, if necessary. | |
144 | */ | |
7c657876 | 145 | dccp_set_state(sk, DCCP_CLOSED); |
e0833d1f | 146 | inet_bhash2_reset_saddr(sk); |
7c657876 ACM |
147 | ip_rt_put(rt); |
148 | sk->sk_route_caps = 0; | |
c720c7e8 | 149 | inet->inet_dport = 0; |
7c657876 ACM |
150 | goto out; |
151 | } | |
f21e68ca ACM |
152 | EXPORT_SYMBOL_GPL(dccp_v4_connect); |
153 | ||
7c657876 ACM |
154 | /* |
155 | * This routine does path mtu discovery as defined in RFC1191. | |
156 | */ | |
157 | static inline void dccp_do_pmtu_discovery(struct sock *sk, | |
158 | const struct iphdr *iph, | |
159 | u32 mtu) | |
160 | { | |
161 | struct dst_entry *dst; | |
162 | const struct inet_sock *inet = inet_sk(sk); | |
163 | const struct dccp_sock *dp = dccp_sk(sk); | |
164 | ||
165 | /* We are not interested in DCCP_LISTEN and request_socks (RESPONSEs | |
166 | * send out by Linux are always < 576bytes so they should go through | |
167 | * unfragmented). | |
168 | */ | |
169 | if (sk->sk_state == DCCP_LISTEN) | |
170 | return; | |
171 | ||
80d0a69f DM |
172 | dst = inet_csk_update_pmtu(sk, mtu); |
173 | if (!dst) | |
7c657876 ACM |
174 | return; |
175 | ||
7c657876 ACM |
176 | /* Something is about to be wrong... Remember soft error |
177 | * for the case, if this connection will not able to recover. | |
178 | */ | |
179 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) | |
9a25f0cb | 180 | WRITE_ONCE(sk->sk_err_soft, EMSGSIZE); |
7c657876 ACM |
181 | |
182 | mtu = dst_mtu(dst); | |
183 | ||
184 | if (inet->pmtudisc != IP_PMTUDISC_DONT && | |
482fc609 | 185 | ip_sk_accept_pmtu(sk) && |
d83d8461 | 186 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
7c657876 ACM |
187 | dccp_sync_mss(sk, mtu); |
188 | ||
189 | /* | |
0e64e94e | 190 | * From RFC 4340, sec. 14.1: |
7c657876 | 191 | * |
7690af3f ACM |
192 | * DCCP-Sync packets are the best choice for upward |
193 | * probing, since DCCP-Sync probes do not risk application | |
194 | * data loss. | |
7c657876 | 195 | */ |
e92ae93a | 196 | dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC); |
7c657876 ACM |
197 | } /* else let the usual retransmit timer handle it */ |
198 | } | |
199 | ||
55be7a9c DM |
200 | static void dccp_do_redirect(struct sk_buff *skb, struct sock *sk) |
201 | { | |
202 | struct dst_entry *dst = __sk_dst_check(sk, 0); | |
203 | ||
1ed5c48f | 204 | if (dst) |
6700c270 | 205 | dst->ops->redirect(dst, sk, skb); |
55be7a9c DM |
206 | } |
207 | ||
85645bab ED |
208 | void dccp_req_err(struct sock *sk, u64 seq) |
209 | { | |
210 | struct request_sock *req = inet_reqsk(sk); | |
211 | struct net *net = sock_net(sk); | |
212 | ||
213 | /* | |
214 | * ICMPs are not backlogged, hence we cannot get an established | |
215 | * socket here. | |
216 | */ | |
85645bab | 217 | if (!between48(seq, dccp_rsk(req)->dreq_iss, dccp_rsk(req)->dreq_gss)) { |
02a1d6e7 | 218 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
85645bab ED |
219 | } else { |
220 | /* | |
221 | * Still in RESPOND, just remove it silently. | |
222 | * There is no good way to pass the error to the newly | |
223 | * created socket, and POSIX does not want network | |
224 | * errors returned from accept(). | |
225 | */ | |
226 | inet_csk_reqsk_queue_drop(req->rsk_listener, req); | |
227 | } | |
ef84d8ce | 228 | reqsk_put(req); |
85645bab ED |
229 | } |
230 | EXPORT_SYMBOL(dccp_req_err); | |
231 | ||
7c657876 ACM |
232 | /* |
233 | * This routine is called by the ICMP module when it gets some sort of error | |
234 | * condition. If err < 0 then the socket should be closed and the error | |
235 | * returned to the user. If err > 0 it's just the icmp type << 8 | icmp code. | |
236 | * After adjustment header points to the first 8 bytes of the tcp header. We | |
237 | * need to find the appropriate port. | |
238 | * | |
239 | * The locking strategy used here is very "optimistic". When someone else | |
240 | * accesses the socket the ICMP is just dropped and for some paths there is no | |
241 | * check at all. A more general error queue to queue errors for later handling | |
242 | * is probably better. | |
243 | */ | |
32bbd879 | 244 | static int dccp_v4_err(struct sk_buff *skb, u32 info) |
7c657876 ACM |
245 | { |
246 | const struct iphdr *iph = (struct iphdr *)skb->data; | |
18e1d836 | 247 | const u8 offset = iph->ihl << 2; |
6706a97f | 248 | const struct dccp_hdr *dh; |
7c657876 | 249 | struct dccp_sock *dp; |
88c7664f ACM |
250 | const int type = icmp_hdr(skb)->type; |
251 | const int code = icmp_hdr(skb)->code; | |
7c657876 ACM |
252 | struct sock *sk; |
253 | __u64 seq; | |
254 | int err; | |
fd54d716 | 255 | struct net *net = dev_net(skb->dev); |
7c657876 | 256 | |
6af28974 ED |
257 | if (!pskb_may_pull(skb, offset + sizeof(*dh))) |
258 | return -EINVAL; | |
977ad86c JH |
259 | dh = (struct dccp_hdr *)(skb->data + offset); |
260 | if (!pskb_may_pull(skb, offset + __dccp_basic_hdr_len(dh))) | |
261 | return -EINVAL; | |
262 | iph = (struct iphdr *)skb->data; | |
6706a97f | 263 | dh = (struct dccp_hdr *)(skb->data + offset); |
7c657876 | 264 | |
85645bab ED |
265 | sk = __inet_lookup_established(net, &dccp_hashinfo, |
266 | iph->daddr, dh->dccph_dport, | |
267 | iph->saddr, ntohs(dh->dccph_sport), | |
3fa6f616 | 268 | inet_iif(skb), 0); |
85645bab | 269 | if (!sk) { |
5d3848bc | 270 | __ICMP_INC_STATS(net, ICMP_MIB_INERRORS); |
32bbd879 | 271 | return -ENOENT; |
7c657876 ACM |
272 | } |
273 | ||
274 | if (sk->sk_state == DCCP_TIME_WAIT) { | |
9469c7b4 | 275 | inet_twsk_put(inet_twsk(sk)); |
32bbd879 | 276 | return 0; |
7c657876 | 277 | } |
85645bab | 278 | seq = dccp_hdr_seq(dh); |
32bbd879 SB |
279 | if (sk->sk_state == DCCP_NEW_SYN_RECV) { |
280 | dccp_req_err(sk, seq); | |
281 | return 0; | |
282 | } | |
7c657876 ACM |
283 | |
284 | bh_lock_sock(sk); | |
285 | /* If too many ICMPs get dropped on busy | |
286 | * servers this needs to be solved differently. | |
287 | */ | |
288 | if (sock_owned_by_user(sk)) | |
02a1d6e7 | 289 | __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); |
7c657876 ACM |
290 | |
291 | if (sk->sk_state == DCCP_CLOSED) | |
292 | goto out; | |
293 | ||
294 | dp = dccp_sk(sk); | |
1238d087 | 295 | if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) && |
d68f0866 | 296 | !between48(seq, dp->dccps_awl, dp->dccps_awh)) { |
02a1d6e7 | 297 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
7c657876 ACM |
298 | goto out; |
299 | } | |
300 | ||
301 | switch (type) { | |
55be7a9c | 302 | case ICMP_REDIRECT: |
45caeaa5 JM |
303 | if (!sock_owned_by_user(sk)) |
304 | dccp_do_redirect(skb, sk); | |
55be7a9c | 305 | goto out; |
7c657876 ACM |
306 | case ICMP_SOURCE_QUENCH: |
307 | /* Just silently ignore these. */ | |
308 | goto out; | |
309 | case ICMP_PARAMETERPROB: | |
310 | err = EPROTO; | |
311 | break; | |
312 | case ICMP_DEST_UNREACH: | |
313 | if (code > NR_ICMP_UNREACH) | |
314 | goto out; | |
315 | ||
316 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ | |
317 | if (!sock_owned_by_user(sk)) | |
318 | dccp_do_pmtu_discovery(sk, iph, info); | |
319 | goto out; | |
320 | } | |
321 | ||
322 | err = icmp_err_convert[code].errno; | |
323 | break; | |
324 | case ICMP_TIME_EXCEEDED: | |
325 | err = EHOSTUNREACH; | |
326 | break; | |
327 | default: | |
328 | goto out; | |
329 | } | |
330 | ||
331 | switch (sk->sk_state) { | |
7c657876 ACM |
332 | case DCCP_REQUESTING: |
333 | case DCCP_RESPOND: | |
334 | if (!sock_owned_by_user(sk)) { | |
aa62d76b | 335 | __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS); |
7c657876 ACM |
336 | sk->sk_err = err; |
337 | ||
e3ae2365 | 338 | sk_error_report(sk); |
7c657876 ACM |
339 | |
340 | dccp_done(sk); | |
9a25f0cb ED |
341 | } else { |
342 | WRITE_ONCE(sk->sk_err_soft, err); | |
343 | } | |
7c657876 ACM |
344 | goto out; |
345 | } | |
346 | ||
347 | /* If we've already connected we will keep trying | |
348 | * until we time out, or the user gives up. | |
349 | * | |
350 | * rfc1122 4.2.3.9 allows to consider as hard errors | |
351 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, | |
352 | * but it is obsoleted by pmtu discovery). | |
353 | * | |
354 | * Note, that in modern internet, where routing is unreliable | |
355 | * and in each dark corner broken firewalls sit, sending random | |
356 | * errors ordered by their masters even this two messages finally lose | |
357 | * their original sense (even Linux sends invalid PORT_UNREACHs) | |
358 | * | |
359 | * Now we are in compliance with RFCs. | |
360 | * --ANK (980905) | |
361 | */ | |
362 | ||
6b5f43ea | 363 | if (!sock_owned_by_user(sk) && inet_test_bit(RECVERR, sk)) { |
7c657876 | 364 | sk->sk_err = err; |
e3ae2365 | 365 | sk_error_report(sk); |
9a25f0cb ED |
366 | } else { /* Only an error on timeout */ |
367 | WRITE_ONCE(sk->sk_err_soft, err); | |
368 | } | |
7c657876 ACM |
369 | out: |
370 | bh_unlock_sock(sk); | |
371 | sock_put(sk); | |
32bbd879 | 372 | return 0; |
7c657876 ACM |
373 | } |
374 | ||
2bda2853 | 375 | static inline __sum16 dccp_v4_csum_finish(struct sk_buff *skb, |
6f4e5fff GR |
376 | __be32 src, __be32 dst) |
377 | { | |
378 | return csum_tcpudp_magic(src, dst, skb->len, IPPROTO_DCCP, skb->csum); | |
379 | } | |
380 | ||
bb296246 | 381 | void dccp_v4_send_check(struct sock *sk, struct sk_buff *skb) |
57cca05a ACM |
382 | { |
383 | const struct inet_sock *inet = inet_sk(sk); | |
384 | struct dccp_hdr *dh = dccp_hdr(skb); | |
385 | ||
6f4e5fff | 386 | dccp_csum_outgoing(skb); |
c720c7e8 ED |
387 | dh->dccph_checksum = dccp_v4_csum_finish(skb, |
388 | inet->inet_saddr, | |
389 | inet->inet_daddr); | |
57cca05a | 390 | } |
f21e68ca ACM |
391 | EXPORT_SYMBOL_GPL(dccp_v4_send_check); |
392 | ||
865e9022 | 393 | static inline u64 dccp_v4_init_sequence(const struct sk_buff *skb) |
7c657876 | 394 | { |
eddc9ec5 ACM |
395 | return secure_dccp_sequence_number(ip_hdr(skb)->daddr, |
396 | ip_hdr(skb)->saddr, | |
7c657876 ACM |
397 | dccp_hdr(skb)->dccph_dport, |
398 | dccp_hdr(skb)->dccph_sport); | |
399 | } | |
400 | ||
7c657876 ACM |
401 | /* |
402 | * The three way handshake has completed - we got a valid ACK or DATAACK - | |
403 | * now create the new socket. | |
404 | * | |
405 | * This is the equivalent of TCP's tcp_v4_syn_recv_sock | |
406 | */ | |
0c27171e ED |
407 | struct sock *dccp_v4_request_recv_sock(const struct sock *sk, |
408 | struct sk_buff *skb, | |
7c657876 | 409 | struct request_sock *req, |
5e0724d0 ED |
410 | struct dst_entry *dst, |
411 | struct request_sock *req_unhash, | |
412 | bool *own_req) | |
7c657876 ACM |
413 | { |
414 | struct inet_request_sock *ireq; | |
415 | struct inet_sock *newinet; | |
7c657876 ACM |
416 | struct sock *newsk; |
417 | ||
418 | if (sk_acceptq_is_full(sk)) | |
419 | goto exit_overflow; | |
420 | ||
7c657876 ACM |
421 | newsk = dccp_create_openreq_child(sk, req, skb); |
422 | if (newsk == NULL) | |
093d2823 | 423 | goto exit_nonewsk; |
7c657876 | 424 | |
7c657876 ACM |
425 | newinet = inet_sk(newsk); |
426 | ireq = inet_rsk(req); | |
d1e559d0 ED |
427 | sk_daddr_set(newsk, ireq->ir_rmt_addr); |
428 | sk_rcv_saddr_set(newsk, ireq->ir_loc_addr); | |
634fb979 | 429 | newinet->inet_saddr = ireq->ir_loc_addr; |
c92e8c02 | 430 | RCU_INIT_POINTER(newinet->inet_opt, rcu_dereference(ireq->ireq_opt)); |
7c657876 | 431 | newinet->mc_index = inet_iif(skb); |
eddc9ec5 | 432 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
f866fbc8 | 433 | atomic_set(&newinet->inet_id, get_random_u16()); |
7c657876 | 434 | |
0e734419 DM |
435 | if (dst == NULL && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL) |
436 | goto put_and_exit; | |
437 | ||
438 | sk_setup_caps(newsk, dst); | |
439 | ||
7c657876 ACM |
440 | dccp_sync_mss(newsk, dst_mtu(dst)); |
441 | ||
0e734419 DM |
442 | if (__inet_inherit_port(sk, newsk) < 0) |
443 | goto put_and_exit; | |
01770a16 | 444 | *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash), NULL); |
c92e8c02 ED |
445 | if (*own_req) |
446 | ireq->ireq_opt = NULL; | |
447 | else | |
448 | newinet->inet_opt = NULL; | |
7c657876 ACM |
449 | return newsk; |
450 | ||
451 | exit_overflow: | |
02a1d6e7 | 452 | __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
093d2823 BS |
453 | exit_nonewsk: |
454 | dst_release(dst); | |
7c657876 | 455 | exit: |
02a1d6e7 | 456 | __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS); |
7c657876 | 457 | return NULL; |
0e734419 | 458 | put_and_exit: |
c92e8c02 | 459 | newinet->inet_opt = NULL; |
e337e24d CP |
460 | inet_csk_prepare_forced_close(newsk); |
461 | dccp_done(newsk); | |
0e734419 | 462 | goto exit; |
7c657876 | 463 | } |
f21e68ca ACM |
464 | EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock); |
465 | ||
f5487398 | 466 | static struct dst_entry* dccp_v4_route_skb(struct net *net, struct sock *sk, |
7c657876 ACM |
467 | struct sk_buff *skb) |
468 | { | |
469 | struct rtable *rt; | |
898f7358 | 470 | const struct iphdr *iph = ip_hdr(skb); |
9d6ec938 | 471 | struct flowi4 fl4 = { |
92101b3b | 472 | .flowi4_oif = inet_iif(skb), |
898f7358 DM |
473 | .daddr = iph->saddr, |
474 | .saddr = iph->daddr, | |
2d6c85ca GN |
475 | .flowi4_tos = ip_sock_rt_tos(sk), |
476 | .flowi4_scope = ip_sock_rt_scope(sk), | |
9d6ec938 | 477 | .flowi4_proto = sk->sk_protocol, |
9cce96df DM |
478 | .fl4_sport = dccp_hdr(skb)->dccph_dport, |
479 | .fl4_dport = dccp_hdr(skb)->dccph_sport, | |
1d28f42c | 480 | }; |
7c657876 | 481 | |
3df98d79 | 482 | security_skb_classify_flow(skb, flowi4_to_flowi_common(&fl4)); |
9d6ec938 | 483 | rt = ip_route_output_flow(net, &fl4, sk); |
b23dd4fe | 484 | if (IS_ERR(rt)) { |
95556a88 | 485 | IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); |
7c657876 ACM |
486 | return NULL; |
487 | } | |
488 | ||
d8d1f30b | 489 | return &rt->dst; |
7c657876 ACM |
490 | } |
491 | ||
ea3bea3a | 492 | static int dccp_v4_send_response(const struct sock *sk, struct request_sock *req) |
3d2fe62b GR |
493 | { |
494 | int err = -1; | |
495 | struct sk_buff *skb; | |
fd80eb94 | 496 | struct dst_entry *dst; |
6bd023f3 | 497 | struct flowi4 fl4; |
3d2fe62b | 498 | |
ba3f7f04 | 499 | dst = inet_csk_route_req(sk, &fl4, req); |
fd80eb94 | 500 | if (dst == NULL) |
3d2fe62b GR |
501 | goto out; |
502 | ||
503 | skb = dccp_make_response(sk, dst, req); | |
504 | if (skb != NULL) { | |
505 | const struct inet_request_sock *ireq = inet_rsk(req); | |
506 | struct dccp_hdr *dh = dccp_hdr(skb); | |
507 | ||
634fb979 ED |
508 | dh->dccph_checksum = dccp_v4_csum_finish(skb, ireq->ir_loc_addr, |
509 | ireq->ir_rmt_addr); | |
2ab2ddd3 | 510 | rcu_read_lock(); |
634fb979 ED |
511 | err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr, |
512 | ireq->ir_rmt_addr, | |
de033b7d | 513 | rcu_dereference(ireq->ireq_opt), |
e08d0b3d | 514 | READ_ONCE(inet_sk(sk)->tos)); |
2ab2ddd3 | 515 | rcu_read_unlock(); |
b9df3cb8 | 516 | err = net_xmit_eval(err); |
3d2fe62b GR |
517 | } |
518 | ||
519 | out: | |
520 | dst_release(dst); | |
521 | return err; | |
522 | } | |
523 | ||
a00e7444 | 524 | static void dccp_v4_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb) |
7c657876 ACM |
525 | { |
526 | int err; | |
eddc9ec5 | 527 | const struct iphdr *rxiph; |
7c657876 ACM |
528 | struct sk_buff *skb; |
529 | struct dst_entry *dst; | |
adf30907 | 530 | struct net *net = dev_net(skb_dst(rxskb)->dev); |
b98b3304 FW |
531 | struct dccp_v4_pernet *pn; |
532 | struct sock *ctl_sk; | |
7c657876 ACM |
533 | |
534 | /* Never send a reset in response to a reset. */ | |
e356d37a | 535 | if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET) |
7c657876 ACM |
536 | return; |
537 | ||
511c3f92 | 538 | if (skb_rtable(rxskb)->rt_type != RTN_LOCAL) |
7c657876 ACM |
539 | return; |
540 | ||
b98b3304 FW |
541 | pn = net_generic(net, dccp_v4_pernet_id); |
542 | ctl_sk = pn->v4_ctl_sk; | |
f5487398 | 543 | dst = dccp_v4_route_skb(net, ctl_sk, rxskb); |
7c657876 ACM |
544 | if (dst == NULL) |
545 | return; | |
546 | ||
7b1cffa8 | 547 | skb = dccp_ctl_make_reset(ctl_sk, rxskb); |
7c657876 ACM |
548 | if (skb == NULL) |
549 | goto out; | |
550 | ||
eddc9ec5 | 551 | rxiph = ip_hdr(rxskb); |
e356d37a GR |
552 | dccp_hdr(skb)->dccph_checksum = dccp_v4_csum_finish(skb, rxiph->saddr, |
553 | rxiph->daddr); | |
adf30907 | 554 | skb_dst_set(skb, dst_clone(dst)); |
7c657876 | 555 | |
95556a88 | 556 | local_bh_disable(); |
7b1cffa8 PE |
557 | bh_lock_sock(ctl_sk); |
558 | err = ip_build_and_send_pkt(skb, ctl_sk, | |
de033b7d WW |
559 | rxiph->daddr, rxiph->saddr, NULL, |
560 | inet_sk(ctl_sk)->tos); | |
7b1cffa8 | 561 | bh_unlock_sock(ctl_sk); |
7c657876 | 562 | |
b9df3cb8 | 563 | if (net_xmit_eval(err) == 0) { |
95556a88 ED |
564 | __DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
565 | __DCCP_INC_STATS(DCCP_MIB_OUTRSTS); | |
7c657876 | 566 | } |
95556a88 | 567 | local_bh_enable(); |
7c657876 | 568 | out: |
95556a88 | 569 | dst_release(dst); |
7c657876 ACM |
570 | } |
571 | ||
3d2fe62b GR |
572 | static void dccp_v4_reqsk_destructor(struct request_sock *req) |
573 | { | |
d99a7bd2 | 574 | dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg); |
c92e8c02 | 575 | kfree(rcu_dereference_protected(inet_rsk(req)->ireq_opt, 1)); |
3d2fe62b GR |
576 | } |
577 | ||
42cb80a2 | 578 | void dccp_syn_ack_timeout(const struct request_sock *req) |
c72e1183 ED |
579 | { |
580 | } | |
581 | EXPORT_SYMBOL(dccp_syn_ack_timeout); | |
582 | ||
3d2fe62b GR |
583 | static struct request_sock_ops dccp_request_sock_ops __read_mostly = { |
584 | .family = PF_INET, | |
585 | .obj_size = sizeof(struct dccp_request_sock), | |
586 | .rtx_syn_ack = dccp_v4_send_response, | |
587 | .send_ack = dccp_reqsk_send_ack, | |
588 | .destructor = dccp_v4_reqsk_destructor, | |
589 | .send_reset = dccp_v4_ctl_send_reset, | |
c72e1183 | 590 | .syn_ack_timeout = dccp_syn_ack_timeout, |
3d2fe62b GR |
591 | }; |
592 | ||
593 | int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) | |
594 | { | |
595 | struct inet_request_sock *ireq; | |
3d2fe62b GR |
596 | struct request_sock *req; |
597 | struct dccp_request_sock *dreq; | |
8109b02b | 598 | const __be32 service = dccp_hdr_request(skb)->dccph_req_service; |
3d2fe62b | 599 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
3d2fe62b GR |
600 | |
601 | /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */ | |
511c3f92 | 602 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
4a5409a5 | 603 | return 0; /* discard, don't send a reset here */ |
3d2fe62b GR |
604 | |
605 | if (dccp_bad_service_code(sk, service)) { | |
4a5409a5 | 606 | dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; |
3d2fe62b | 607 | goto drop; |
8109b02b | 608 | } |
3d2fe62b GR |
609 | /* |
610 | * TW buckets are converted to open requests without | |
611 | * limitations, they conserve resources and peer is | |
612 | * evidently real one. | |
613 | */ | |
4a5409a5 | 614 | dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; |
3d2fe62b GR |
615 | if (inet_csk_reqsk_queue_is_full(sk)) |
616 | goto drop; | |
617 | ||
5ea8ea2c | 618 | if (sk_acceptq_is_full(sk)) |
3d2fe62b GR |
619 | goto drop; |
620 | ||
a1a5344d | 621 | req = inet_reqsk_alloc(&dccp_request_sock_ops, sk, true); |
3d2fe62b GR |
622 | if (req == NULL) |
623 | goto drop; | |
624 | ||
ac75773c GR |
625 | if (dccp_reqsk_init(req, dccp_sk(sk), skb)) |
626 | goto drop_and_free; | |
3d2fe62b | 627 | |
8b819412 GR |
628 | dreq = dccp_rsk(req); |
629 | if (dccp_parse_options(sk, dreq, skb)) | |
630 | goto drop_and_free; | |
631 | ||
3d2fe62b | 632 | ireq = inet_rsk(req); |
08d2cc3b ED |
633 | sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); |
634 | sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); | |
b855ff82 | 635 | ireq->ir_mark = inet_request_mark(sk, skb); |
3f66b083 | 636 | ireq->ireq_family = AF_INET; |
36f7cec4 | 637 | ireq->ir_iif = READ_ONCE(sk->sk_bound_dev_if); |
3d2fe62b | 638 | |
fa2df45a KI |
639 | if (security_inet_conn_request(sk, skb, req)) |
640 | goto drop_and_free; | |
641 | ||
8109b02b | 642 | /* |
3d2fe62b GR |
643 | * Step 3: Process LISTEN state |
644 | * | |
645 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie | |
646 | * | |
f541fb7e | 647 | * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child(). |
3d2fe62b | 648 | */ |
3d2fe62b | 649 | dreq->dreq_isr = dcb->dccpd_seq; |
f541fb7e | 650 | dreq->dreq_gsr = dreq->dreq_isr; |
865e9022 | 651 | dreq->dreq_iss = dccp_v4_init_sequence(skb); |
f541fb7e | 652 | dreq->dreq_gss = dreq->dreq_iss; |
3d2fe62b GR |
653 | dreq->dreq_service = service; |
654 | ||
1a2c6181 | 655 | if (dccp_v4_send_response(sk, req)) |
3d2fe62b GR |
656 | goto drop_and_free; |
657 | ||
658 | inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); | |
b7953d3c | 659 | reqsk_put(req); |
3d2fe62b GR |
660 | return 0; |
661 | ||
662 | drop_and_free: | |
663 | reqsk_free(req); | |
664 | drop: | |
aa62d76b | 665 | __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS); |
3d2fe62b GR |
666 | return -1; |
667 | } | |
3d2fe62b GR |
668 | EXPORT_SYMBOL_GPL(dccp_v4_conn_request); |
669 | ||
7c657876 ACM |
670 | int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) |
671 | { | |
672 | struct dccp_hdr *dh = dccp_hdr(skb); | |
673 | ||
674 | if (sk->sk_state == DCCP_OPEN) { /* Fast path */ | |
675 | if (dccp_rcv_established(sk, skb, dh, skb->len)) | |
676 | goto reset; | |
677 | return 0; | |
678 | } | |
679 | ||
680 | /* | |
681 | * Step 3: Process LISTEN state | |
d83ca5ac GR |
682 | * If P.type == Request or P contains a valid Init Cookie option, |
683 | * (* Must scan the packet's options to check for Init | |
684 | * Cookies. Only Init Cookies are processed here, | |
685 | * however; other options are processed in Step 8. This | |
686 | * scan need only be performed if the endpoint uses Init | |
687 | * Cookies *) | |
688 | * (* Generate a new socket and switch to that socket *) | |
689 | * Set S := new socket for this port pair | |
690 | * S.state = RESPOND | |
691 | * Choose S.ISS (initial seqno) or set from Init Cookies | |
692 | * Initialize S.GAR := S.ISS | |
693 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies | |
694 | * Continue with S.state == RESPOND | |
695 | * (* A Response packet will be generated in Step 11 *) | |
696 | * Otherwise, | |
697 | * Generate Reset(No Connection) unless P.type == Reset | |
698 | * Drop packet and return | |
7c657876 | 699 | * |
7690af3f ACM |
700 | * NOTE: the check for the packet types is done in |
701 | * dccp_rcv_state_process | |
7c657876 | 702 | */ |
7c657876 ACM |
703 | |
704 | if (dccp_rcv_state_process(sk, skb, dh, skb->len)) | |
705 | goto reset; | |
706 | return 0; | |
707 | ||
708 | reset: | |
cfb6eeb4 | 709 | dccp_v4_ctl_send_reset(sk, skb); |
7c657876 ACM |
710 | kfree_skb(skb); |
711 | return 0; | |
712 | } | |
f21e68ca ACM |
713 | EXPORT_SYMBOL_GPL(dccp_v4_do_rcv); |
714 | ||
09dbc389 GR |
715 | /** |
716 | * dccp_invalid_packet - check for malformed packets | |
d0b1101b AL |
717 | * @skb: Packet to validate |
718 | * | |
09dbc389 GR |
719 | * Implements RFC 4340, 8.5: Step 1: Check header basics |
720 | * Packets that fail these checks are ignored and do not receive Resets. | |
721 | */ | |
f21e68ca | 722 | int dccp_invalid_packet(struct sk_buff *skb) |
7c657876 ACM |
723 | { |
724 | const struct dccp_hdr *dh; | |
6f4e5fff | 725 | unsigned int cscov; |
648f0c28 | 726 | u8 dccph_doff; |
7c657876 ACM |
727 | |
728 | if (skb->pkt_type != PACKET_HOST) | |
729 | return 1; | |
730 | ||
09dbc389 | 731 | /* If the packet is shorter than 12 bytes, drop packet and return */ |
7c657876 | 732 | if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) { |
59348b19 | 733 | DCCP_WARN("pskb_may_pull failed\n"); |
7c657876 ACM |
734 | return 1; |
735 | } | |
736 | ||
737 | dh = dccp_hdr(skb); | |
738 | ||
09dbc389 | 739 | /* If P.type is not understood, drop packet and return */ |
7c657876 | 740 | if (dh->dccph_type >= DCCP_PKT_INVALID) { |
59348b19 | 741 | DCCP_WARN("invalid packet type\n"); |
7c657876 ACM |
742 | return 1; |
743 | } | |
744 | ||
745 | /* | |
09dbc389 | 746 | * If P.Data Offset is too small for packet type, drop packet and return |
7c657876 | 747 | */ |
648f0c28 ED |
748 | dccph_doff = dh->dccph_doff; |
749 | if (dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) { | |
750 | DCCP_WARN("P.Data Offset(%u) too small\n", dccph_doff); | |
7c657876 ACM |
751 | return 1; |
752 | } | |
09dbc389 | 753 | /* |
54633527 | 754 | * If P.Data Offset is too large for packet, drop packet and return |
09dbc389 | 755 | */ |
648f0c28 ED |
756 | if (!pskb_may_pull(skb, dccph_doff * sizeof(u32))) { |
757 | DCCP_WARN("P.Data Offset(%u) too large\n", dccph_doff); | |
7c657876 ACM |
758 | return 1; |
759 | } | |
648f0c28 | 760 | dh = dccp_hdr(skb); |
7c657876 ACM |
761 | /* |
762 | * If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet | |
763 | * has short sequence numbers), drop packet and return | |
764 | */ | |
6079a463 WY |
765 | if ((dh->dccph_type < DCCP_PKT_DATA || |
766 | dh->dccph_type > DCCP_PKT_DATAACK) && dh->dccph_x == 0) { | |
59348b19 GR |
767 | DCCP_WARN("P.type (%s) not Data || [Data]Ack, while P.X == 0\n", |
768 | dccp_packet_name(dh->dccph_type)); | |
7c657876 ACM |
769 | return 1; |
770 | } | |
771 | ||
6f4e5fff GR |
772 | /* |
773 | * If P.CsCov is too large for the packet size, drop packet and return. | |
774 | * This must come _before_ checksumming (not as RFC 4340 suggests). | |
775 | */ | |
776 | cscov = dccp_csum_coverage(skb); | |
777 | if (cscov > skb->len) { | |
59348b19 GR |
778 | DCCP_WARN("P.CsCov %u exceeds packet length %d\n", |
779 | dh->dccph_cscov, skb->len); | |
6f4e5fff GR |
780 | return 1; |
781 | } | |
782 | ||
783 | /* If header checksum is incorrect, drop packet and return. | |
784 | * (This step is completed in the AF-dependent functions.) */ | |
785 | skb->csum = skb_checksum(skb, 0, cscov, 0); | |
786 | ||
7c657876 ACM |
787 | return 0; |
788 | } | |
f21e68ca ACM |
789 | EXPORT_SYMBOL_GPL(dccp_invalid_packet); |
790 | ||
7c657876 | 791 | /* this is called when real data arrives */ |
b61fafc4 | 792 | static int dccp_v4_rcv(struct sk_buff *skb) |
7c657876 ACM |
793 | { |
794 | const struct dccp_hdr *dh; | |
eddc9ec5 | 795 | const struct iphdr *iph; |
3b24d854 | 796 | bool refcounted; |
7c657876 | 797 | struct sock *sk; |
6f4e5fff | 798 | int min_cov; |
7c657876 | 799 | |
6f4e5fff | 800 | /* Step 1: Check header basics */ |
7c657876 ACM |
801 | |
802 | if (dccp_invalid_packet(skb)) | |
803 | goto discard_it; | |
804 | ||
eddc9ec5 | 805 | iph = ip_hdr(skb); |
6f4e5fff | 806 | /* Step 1: If header checksum is incorrect, drop packet and return */ |
eddc9ec5 | 807 | if (dccp_v4_csum_finish(skb, iph->saddr, iph->daddr)) { |
59348b19 | 808 | DCCP_WARN("dropped packet with invalid checksum\n"); |
f21e68ca ACM |
809 | goto discard_it; |
810 | } | |
811 | ||
7c657876 | 812 | dh = dccp_hdr(skb); |
7c657876 | 813 | |
fde20105 | 814 | DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh); |
7c657876 ACM |
815 | DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type; |
816 | ||
21454aaa | 817 | dccp_pr_debug("%8.8s src=%pI4@%-5d dst=%pI4@%-5d seq=%llu", |
7c657876 | 818 | dccp_packet_name(dh->dccph_type), |
21454aaa HH |
819 | &iph->saddr, ntohs(dh->dccph_sport), |
820 | &iph->daddr, ntohs(dh->dccph_dport), | |
f6ccf554 | 821 | (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq); |
7c657876 ACM |
822 | |
823 | if (dccp_packet_without_ack(skb)) { | |
824 | DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ; | |
825 | dccp_pr_debug_cat("\n"); | |
826 | } else { | |
827 | DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb); | |
d23c7107 | 828 | dccp_pr_debug_cat(", ack=%llu\n", (unsigned long long) |
f6ccf554 | 829 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
7c657876 ACM |
830 | } |
831 | ||
4bdc3d66 | 832 | lookup: |
a583636a | 833 | sk = __inet_lookup_skb(&dccp_hashinfo, skb, __dccp_hdr_len(dh), |
3fa6f616 | 834 | dh->dccph_sport, dh->dccph_dport, 0, &refcounted); |
4bdc3d66 | 835 | if (!sk) { |
7c657876 ACM |
836 | dccp_pr_debug("failed to look up flow ID in table and " |
837 | "get corresponding socket\n"); | |
838 | goto no_dccp_socket; | |
839 | } | |
840 | ||
8109b02b | 841 | /* |
7c657876 | 842 | * Step 2: |
8109b02b | 843 | * ... or S.state == TIMEWAIT, |
7c657876 ACM |
844 | * Generate Reset(No Connection) unless P.type == Reset |
845 | * Drop packet and return | |
846 | */ | |
7c657876 | 847 | if (sk->sk_state == DCCP_TIME_WAIT) { |
d23c7107 GR |
848 | dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n"); |
849 | inet_twsk_put(inet_twsk(sk)); | |
850 | goto no_dccp_socket; | |
7c657876 ACM |
851 | } |
852 | ||
079096f1 ED |
853 | if (sk->sk_state == DCCP_NEW_SYN_RECV) { |
854 | struct request_sock *req = inet_reqsk(sk); | |
7716682c | 855 | struct sock *nsk; |
079096f1 ED |
856 | |
857 | sk = req->rsk_listener; | |
7716682c | 858 | if (unlikely(sk->sk_state != DCCP_LISTEN)) { |
f03f2e15 | 859 | inet_csk_reqsk_queue_drop_and_put(sk, req); |
4bdc3d66 ED |
860 | goto lookup; |
861 | } | |
7716682c | 862 | sock_hold(sk); |
3b24d854 | 863 | refcounted = true; |
7716682c | 864 | nsk = dccp_check_req(sk, skb, req); |
079096f1 ED |
865 | if (!nsk) { |
866 | reqsk_put(req); | |
7716682c | 867 | goto discard_and_relse; |
079096f1 ED |
868 | } |
869 | if (nsk == sk) { | |
079096f1 ED |
870 | reqsk_put(req); |
871 | } else if (dccp_child_process(sk, nsk, skb)) { | |
872 | dccp_v4_ctl_send_reset(sk, skb); | |
7716682c | 873 | goto discard_and_relse; |
079096f1 | 874 | } else { |
7716682c | 875 | sock_put(sk); |
079096f1 ED |
876 | return 0; |
877 | } | |
878 | } | |
6f4e5fff GR |
879 | /* |
880 | * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage | |
8109b02b ACM |
881 | * o if MinCsCov = 0, only packets with CsCov = 0 are accepted |
882 | * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov | |
6f4e5fff GR |
883 | */ |
884 | min_cov = dccp_sk(sk)->dccps_pcrlen; | |
885 | if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) { | |
886 | dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n", | |
887 | dh->dccph_cscov, min_cov); | |
888 | /* FIXME: "Such packets SHOULD be reported using Data Dropped | |
889 | * options (Section 11.7) with Drop Code 0, Protocol | |
890 | * Constraints." */ | |
891 | goto discard_and_relse; | |
892 | } | |
893 | ||
25995ff5 | 894 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
7c657876 | 895 | goto discard_and_relse; |
895b5c9f | 896 | nf_reset_ct(skb); |
7c657876 | 897 | |
c3f24cfb | 898 | return __sk_receive_skb(sk, skb, 1, dh->dccph_doff * 4, refcounted); |
7c657876 ACM |
899 | |
900 | no_dccp_socket: | |
901 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) | |
902 | goto discard_it; | |
903 | /* | |
904 | * Step 2: | |
8109b02b | 905 | * If no socket ... |
7c657876 ACM |
906 | * Generate Reset(No Connection) unless P.type == Reset |
907 | * Drop packet and return | |
908 | */ | |
909 | if (dh->dccph_type != DCCP_PKT_RESET) { | |
7690af3f ACM |
910 | DCCP_SKB_CB(skb)->dccpd_reset_code = |
911 | DCCP_RESET_CODE_NO_CONNECTION; | |
cfb6eeb4 | 912 | dccp_v4_ctl_send_reset(sk, skb); |
7c657876 ACM |
913 | } |
914 | ||
915 | discard_it: | |
7c657876 ACM |
916 | kfree_skb(skb); |
917 | return 0; | |
918 | ||
919 | discard_and_relse: | |
3b24d854 ED |
920 | if (refcounted) |
921 | sock_put(sk); | |
7c657876 ACM |
922 | goto discard_it; |
923 | } | |
924 | ||
3b401a81 | 925 | static const struct inet_connection_sock_af_ops dccp_ipv4_af_ops = { |
543d9cfe ACM |
926 | .queue_xmit = ip_queue_xmit, |
927 | .send_check = dccp_v4_send_check, | |
928 | .rebuild_header = inet_sk_rebuild_header, | |
929 | .conn_request = dccp_v4_conn_request, | |
930 | .syn_recv_sock = dccp_v4_request_recv_sock, | |
931 | .net_header_len = sizeof(struct iphdr), | |
932 | .setsockopt = ip_setsockopt, | |
933 | .getsockopt = ip_getsockopt, | |
934 | .addr2sockaddr = inet_csk_addr2sockaddr, | |
935 | .sockaddr_len = sizeof(struct sockaddr_in), | |
57cca05a ACM |
936 | }; |
937 | ||
3e0fadc5 | 938 | static int dccp_v4_init_sock(struct sock *sk) |
7c657876 | 939 | { |
72478873 ACM |
940 | static __u8 dccp_v4_ctl_sock_initialized; |
941 | int err = dccp_init_sock(sk, dccp_v4_ctl_sock_initialized); | |
f21e68ca | 942 | |
72478873 ACM |
943 | if (err == 0) { |
944 | if (unlikely(!dccp_v4_ctl_sock_initialized)) | |
945 | dccp_v4_ctl_sock_initialized = 1; | |
3e0fadc5 | 946 | inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops; |
72478873 ACM |
947 | } |
948 | ||
3e0fadc5 | 949 | return err; |
7c657876 ACM |
950 | } |
951 | ||
6d6ee43e ACM |
952 | static struct timewait_sock_ops dccp_timewait_sock_ops = { |
953 | .twsk_obj_size = sizeof(struct inet_timewait_sock), | |
954 | }; | |
955 | ||
5e0817f8 | 956 | static struct proto dccp_v4_prot = { |
7c657876 ACM |
957 | .name = "DCCP", |
958 | .owner = THIS_MODULE, | |
959 | .close = dccp_close, | |
960 | .connect = dccp_v4_connect, | |
961 | .disconnect = dccp_disconnect, | |
962 | .ioctl = dccp_ioctl, | |
963 | .init = dccp_v4_init_sock, | |
964 | .setsockopt = dccp_setsockopt, | |
965 | .getsockopt = dccp_getsockopt, | |
966 | .sendmsg = dccp_sendmsg, | |
967 | .recvmsg = dccp_recvmsg, | |
968 | .backlog_rcv = dccp_v4_do_rcv, | |
ab1e0a13 ACM |
969 | .hash = inet_hash, |
970 | .unhash = inet_unhash, | |
7c657876 | 971 | .accept = inet_csk_accept, |
ab1e0a13 | 972 | .get_port = inet_csk_get_port, |
7c657876 | 973 | .shutdown = dccp_shutdown, |
3e0fadc5 | 974 | .destroy = dccp_destroy_sock, |
7c657876 ACM |
975 | .orphan_count = &dccp_orphan_count, |
976 | .max_header = MAX_DCCP_HEADER, | |
977 | .obj_size = sizeof(struct dccp_sock), | |
5f0d5a3a | 978 | .slab_flags = SLAB_TYPESAFE_BY_RCU, |
7c657876 | 979 | .rsk_prot = &dccp_request_sock_ops, |
6d6ee43e | 980 | .twsk_prot = &dccp_timewait_sock_ops, |
39d8cda7 | 981 | .h.hashinfo = &dccp_hashinfo, |
7c657876 | 982 | }; |
6d6ee43e | 983 | |
32613090 | 984 | static const struct net_protocol dccp_v4_protocol = { |
b61fafc4 ACM |
985 | .handler = dccp_v4_rcv, |
986 | .err_handler = dccp_v4_err, | |
987 | .no_policy = 1, | |
8ed1dc44 | 988 | .icmp_strict_tag_validation = 1, |
b61fafc4 ACM |
989 | }; |
990 | ||
991 | static const struct proto_ops inet_dccp_ops = { | |
543d9cfe ACM |
992 | .family = PF_INET, |
993 | .owner = THIS_MODULE, | |
994 | .release = inet_release, | |
995 | .bind = inet_bind, | |
996 | .connect = inet_stream_connect, | |
997 | .socketpair = sock_no_socketpair, | |
998 | .accept = inet_accept, | |
999 | .getname = inet_getname, | |
b61fafc4 | 1000 | /* FIXME: work on tcp_poll to rename it to inet_csk_poll */ |
a11e1d43 | 1001 | .poll = dccp_poll, |
543d9cfe | 1002 | .ioctl = inet_ioctl, |
c7cbdbf2 | 1003 | .gettstamp = sock_gettstamp, |
b61fafc4 | 1004 | /* FIXME: work on inet_listen to rename it to sock_common_listen */ |
543d9cfe ACM |
1005 | .listen = inet_dccp_listen, |
1006 | .shutdown = inet_shutdown, | |
1007 | .setsockopt = sock_common_setsockopt, | |
1008 | .getsockopt = sock_common_getsockopt, | |
1009 | .sendmsg = inet_sendmsg, | |
1010 | .recvmsg = sock_common_recvmsg, | |
1011 | .mmap = sock_no_mmap, | |
b61fafc4 ACM |
1012 | }; |
1013 | ||
1014 | static struct inet_protosw dccp_v4_protosw = { | |
1015 | .type = SOCK_DCCP, | |
1016 | .protocol = IPPROTO_DCCP, | |
1017 | .prot = &dccp_v4_prot, | |
1018 | .ops = &inet_dccp_ops, | |
b61fafc4 ACM |
1019 | .flags = INET_PROTOSW_ICSK, |
1020 | }; | |
1021 | ||
2c8c1e72 | 1022 | static int __net_init dccp_v4_init_net(struct net *net) |
72a2d613 | 1023 | { |
b98b3304 FW |
1024 | struct dccp_v4_pernet *pn = net_generic(net, dccp_v4_pernet_id); |
1025 | ||
d14a0ebd GR |
1026 | if (dccp_hashinfo.bhash == NULL) |
1027 | return -ESOCKTNOSUPPORT; | |
b76c4b27 | 1028 | |
b98b3304 | 1029 | return inet_ctl_sock_create(&pn->v4_ctl_sk, PF_INET, |
d14a0ebd | 1030 | SOCK_DCCP, IPPROTO_DCCP, net); |
72a2d613 PE |
1031 | } |
1032 | ||
2c8c1e72 | 1033 | static void __net_exit dccp_v4_exit_net(struct net *net) |
72a2d613 | 1034 | { |
b98b3304 FW |
1035 | struct dccp_v4_pernet *pn = net_generic(net, dccp_v4_pernet_id); |
1036 | ||
1037 | inet_ctl_sock_destroy(pn->v4_ctl_sk); | |
72a2d613 PE |
1038 | } |
1039 | ||
04c494e6 ED |
1040 | static void __net_exit dccp_v4_exit_batch(struct list_head *net_exit_list) |
1041 | { | |
1042 | inet_twsk_purge(&dccp_hashinfo, AF_INET); | |
1043 | } | |
1044 | ||
72a2d613 PE |
1045 | static struct pernet_operations dccp_v4_ops = { |
1046 | .init = dccp_v4_init_net, | |
1047 | .exit = dccp_v4_exit_net, | |
04c494e6 | 1048 | .exit_batch = dccp_v4_exit_batch, |
b98b3304 FW |
1049 | .id = &dccp_v4_pernet_id, |
1050 | .size = sizeof(struct dccp_v4_pernet), | |
72a2d613 PE |
1051 | }; |
1052 | ||
b61fafc4 ACM |
1053 | static int __init dccp_v4_init(void) |
1054 | { | |
1055 | int err = proto_register(&dccp_v4_prot, 1); | |
1056 | ||
d5494acb | 1057 | if (err) |
b61fafc4 ACM |
1058 | goto out; |
1059 | ||
b61fafc4 ACM |
1060 | inet_register_protosw(&dccp_v4_protosw); |
1061 | ||
72a2d613 PE |
1062 | err = register_pernet_subsys(&dccp_v4_ops); |
1063 | if (err) | |
1064 | goto out_destroy_ctl_sock; | |
d5494acb XL |
1065 | |
1066 | err = inet_add_protocol(&dccp_v4_protocol, IPPROTO_DCCP); | |
1067 | if (err) | |
1068 | goto out_proto_unregister; | |
1069 | ||
b61fafc4 ACM |
1070 | out: |
1071 | return err; | |
d5494acb XL |
1072 | out_proto_unregister: |
1073 | unregister_pernet_subsys(&dccp_v4_ops); | |
72a2d613 | 1074 | out_destroy_ctl_sock: |
b61fafc4 | 1075 | inet_unregister_protosw(&dccp_v4_protosw); |
b61fafc4 ACM |
1076 | proto_unregister(&dccp_v4_prot); |
1077 | goto out; | |
1078 | } | |
1079 | ||
1080 | static void __exit dccp_v4_exit(void) | |
1081 | { | |
d5494acb | 1082 | inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP); |
72a2d613 | 1083 | unregister_pernet_subsys(&dccp_v4_ops); |
b61fafc4 | 1084 | inet_unregister_protosw(&dccp_v4_protosw); |
b61fafc4 ACM |
1085 | proto_unregister(&dccp_v4_prot); |
1086 | } | |
1087 | ||
1088 | module_init(dccp_v4_init); | |
1089 | module_exit(dccp_v4_exit); | |
1090 | ||
1091 | /* | |
1092 | * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33) | |
1093 | * values directly, Also cover the case where the protocol is not specified, | |
1094 | * i.e. net-pf-PF_INET-proto-0-type-SOCK_DCCP | |
1095 | */ | |
7131c6c7 JD |
1096 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 33, 6); |
1097 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 0, 6); | |
b61fafc4 ACM |
1098 | MODULE_LICENSE("GPL"); |
1099 | MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>"); | |
1100 | MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol"); |