1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * net/dccp/ipv4.c |
4 | * |
5 | * An implementation of the DCCP protocol |
6 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
7 | */ |
8 | |
9 | #include <linux/dccp.h> |
10 | #include <linux/icmp.h> |
11 | #include <linux/slab.h> |
12 | #include <linux/module.h> |
13 | #include <linux/skbuff.h> |
14 | #include <linux/random.h> |
15 | |
16 | #include <net/icmp.h> |
17 | #include <net/inet_common.h> |
18 | #include <net/inet_hashtables.h> |
19 | #include <net/inet_sock.h> |
20 | #include <net/protocol.h> |
21 | #include <net/sock.h> |
22 | #include <net/timewait_sock.h> |
23 | #include <net/tcp_states.h> |
24 | #include <net/xfrm.h> |
25 | #include <net/secure_seq.h> |
26 | #include <net/netns/generic.h> |
27 | |
28 | #include "ackvec.h" |
29 | #include "ccid.h" |
30 | #include "dccp.h" |
31 | #include "feat.h" |
32 | |
33 | struct dccp_v4_pernet { |
34 | struct sock *v4_ctl_sk; |
35 | }; |
36 | |
37 | static unsigned int dccp_v4_pernet_id __read_mostly; |
38 | |
39 | /* |
40 | * The per-net v4_ctl_sk socket is used for responding to |
41 | * the Out-of-the-blue (OOTB) packets. A control sock will be created |
42 | * for this socket at the initialization time. |
43 | */ |
44 | |
45 | int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) |
46 | { |
47 | const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
48 | struct inet_sock *inet = inet_sk(sk); |
49 | struct dccp_sock *dp = dccp_sk(sk); |
50 | __be16 orig_sport, orig_dport; |
51 | __be32 daddr, nexthop; |
52 | struct flowi4 *fl4; |
53 | struct rtable *rt; |
54 | int err; |
55 | struct ip_options_rcu *inet_opt; |
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; |
66 | |
67 | inet_opt = rcu_dereference_protected(inet->inet_opt, |
68 | lockdep_sock_is_held(sk)); |
69 | if (inet_opt != NULL && inet_opt->opt.srr) { |
70 | if (daddr == 0) |
71 | return -EINVAL; |
72 | nexthop = inet_opt->opt.faddr; |
73 | } |
74 | |
75 | orig_sport = inet->inet_sport; |
76 | orig_dport = usin->sin_port; |
77 | fl4 = &inet->cork.fl.u.ip4; |
78 | rt = ip_route_connect(fl4, dst: nexthop, src: inet->inet_saddr, |
79 | oif: sk->sk_bound_dev_if, IPPROTO_DCCP, sport: orig_sport, |
80 | dport: orig_dport, sk); |
81 | if (IS_ERR(ptr: rt)) |
82 | return PTR_ERR(ptr: rt); |
83 | |
84 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { |
85 | ip_rt_put(rt); |
86 | return -ENETUNREACH; |
87 | } |
88 | |
89 | if (inet_opt == NULL || !inet_opt->opt.srr) |
90 | daddr = fl4->daddr; |
91 | |
92 | if (inet->inet_saddr == 0) { |
93 | err = inet_bhash2_update_saddr(sk, saddr: &fl4->saddr, AF_INET); |
94 | if (err) { |
95 | ip_rt_put(rt); |
96 | return err; |
97 | } |
98 | } else { |
99 | sk_rcv_saddr_set(sk, addr: inet->inet_saddr); |
100 | } |
101 | |
102 | inet->inet_dport = usin->sin_port; |
103 | sk_daddr_set(sk, addr: daddr); |
104 | |
105 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
106 | if (inet_opt) |
107 | inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; |
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, state: DCCP_REQUESTING); |
115 | err = inet_hash_connect(death_row: &dccp_death_row, sk); |
116 | if (err != 0) |
117 | goto failure; |
118 | |
119 | rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, |
120 | sport: inet->inet_sport, dport: inet->inet_dport, sk); |
121 | if (IS_ERR(ptr: rt)) { |
122 | err = PTR_ERR(ptr: rt); |
123 | rt = NULL; |
124 | goto failure; |
125 | } |
126 | /* OK, now commit destination to socket. */ |
127 | sk_setup_caps(sk, dst: &rt->dst); |
128 | |
129 | dp->dccps_iss = secure_dccp_sequence_number(saddr: inet->inet_saddr, |
130 | daddr: inet->inet_daddr, |
131 | sport: inet->inet_sport, |
132 | dport: inet->inet_dport); |
133 | atomic_set(v: &inet->inet_id, i: get_random_u16()); |
134 | |
135 | err = dccp_connect(sk); |
136 | rt = NULL; |
137 | if (err != 0) |
138 | goto failure; |
139 | out: |
140 | return err; |
141 | failure: |
142 | /* |
143 | * This unhashes the socket and releases the local port, if necessary. |
144 | */ |
145 | dccp_set_state(sk, state: DCCP_CLOSED); |
146 | inet_bhash2_reset_saddr(sk); |
147 | ip_rt_put(rt); |
148 | sk->sk_route_caps = 0; |
149 | inet->inet_dport = 0; |
150 | goto out; |
151 | } |
152 | EXPORT_SYMBOL_GPL(dccp_v4_connect); |
153 | |
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 | |
172 | dst = inet_csk_update_pmtu(sk, mtu); |
173 | if (!dst) |
174 | return; |
175 | |
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)) |
180 | WRITE_ONCE(sk->sk_err_soft, EMSGSIZE); |
181 | |
182 | mtu = dst_mtu(dst); |
183 | |
184 | if (inet->pmtudisc != IP_PMTUDISC_DONT && |
185 | ip_sk_accept_pmtu(sk) && |
186 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
187 | dccp_sync_mss(sk, pmtu: mtu); |
188 | |
189 | /* |
190 | * From RFC 4340, sec. 14.1: |
191 | * |
192 | * DCCP-Sync packets are the best choice for upward |
193 | * probing, since DCCP-Sync probes do not risk application |
194 | * data loss. |
195 | */ |
196 | dccp_send_sync(sk, seq: dp->dccps_gsr, pkt_type: DCCP_PKT_SYNC); |
197 | } /* else let the usual retransmit timer handle it */ |
198 | } |
199 | |
200 | static void dccp_do_redirect(struct sk_buff *skb, struct sock *sk) |
201 | { |
202 | struct dst_entry *dst = __sk_dst_check(sk, cookie: 0); |
203 | |
204 | if (dst) |
205 | dst->ops->redirect(dst, sk, skb); |
206 | } |
207 | |
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 | */ |
217 | if (!between48(seq1: seq, seq2: dccp_rsk(req)->dreq_iss, seq3: dccp_rsk(req)->dreq_gss)) { |
218 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
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(sk: req->rsk_listener, req); |
227 | } |
228 | reqsk_put(req); |
229 | } |
230 | EXPORT_SYMBOL(dccp_req_err); |
231 | |
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 | */ |
244 | static int dccp_v4_err(struct sk_buff *skb, u32 info) |
245 | { |
246 | const struct iphdr *iph = (struct iphdr *)skb->data; |
247 | const u8 offset = iph->ihl << 2; |
248 | const struct dccp_hdr *dh; |
249 | struct dccp_sock *dp; |
250 | const int type = icmp_hdr(skb)->type; |
251 | const int code = icmp_hdr(skb)->code; |
252 | struct sock *sk; |
253 | __u64 seq; |
254 | int err; |
255 | struct net *net = dev_net(dev: skb->dev); |
256 | |
257 | if (!pskb_may_pull(skb, len: offset + sizeof(*dh))) |
258 | return -EINVAL; |
259 | dh = (struct dccp_hdr *)(skb->data + offset); |
260 | if (!pskb_may_pull(skb, len: offset + __dccp_basic_hdr_len(dh))) |
261 | return -EINVAL; |
262 | iph = (struct iphdr *)skb->data; |
263 | dh = (struct dccp_hdr *)(skb->data + offset); |
264 | |
265 | sk = __inet_lookup_established(net, hashinfo: &dccp_hashinfo, |
266 | saddr: iph->daddr, sport: dh->dccph_dport, |
267 | daddr: iph->saddr, ntohs(dh->dccph_sport), |
268 | dif: inet_iif(skb), sdif: 0); |
269 | if (!sk) { |
270 | __ICMP_INC_STATS(net, ICMP_MIB_INERRORS); |
271 | return -ENOENT; |
272 | } |
273 | |
274 | if (sk->sk_state == DCCP_TIME_WAIT) { |
275 | inet_twsk_put(tw: inet_twsk(sk)); |
276 | return 0; |
277 | } |
278 | seq = dccp_hdr_seq(dh); |
279 | if (sk->sk_state == DCCP_NEW_SYN_RECV) { |
280 | dccp_req_err(sk, seq); |
281 | return 0; |
282 | } |
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)) |
289 | __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); |
290 | |
291 | if (sk->sk_state == DCCP_CLOSED) |
292 | goto out; |
293 | |
294 | dp = dccp_sk(sk); |
295 | if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) && |
296 | !between48(seq1: seq, seq2: dp->dccps_awl, seq3: dp->dccps_awh)) { |
297 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
298 | goto out; |
299 | } |
300 | |
301 | switch (type) { |
302 | case ICMP_REDIRECT: |
303 | if (!sock_owned_by_user(sk)) |
304 | dccp_do_redirect(skb, sk); |
305 | goto out; |
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, mtu: 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) { |
332 | case DCCP_REQUESTING: |
333 | case DCCP_RESPOND: |
334 | if (!sock_owned_by_user(sk)) { |
335 | __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS); |
336 | sk->sk_err = err; |
337 | |
338 | sk_error_report(sk); |
339 | |
340 | dccp_done(sk); |
341 | } else { |
342 | WRITE_ONCE(sk->sk_err_soft, err); |
343 | } |
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 | |
363 | if (!sock_owned_by_user(sk) && inet_test_bit(RECVERR, sk)) { |
364 | sk->sk_err = err; |
365 | sk_error_report(sk); |
366 | } else { /* Only an error on timeout */ |
367 | WRITE_ONCE(sk->sk_err_soft, err); |
368 | } |
369 | out: |
370 | bh_unlock_sock(sk); |
371 | sock_put(sk); |
372 | return 0; |
373 | } |
374 | |
375 | static inline __sum16 dccp_v4_csum_finish(struct sk_buff *skb, |
376 | __be32 src, __be32 dst) |
377 | { |
378 | return csum_tcpudp_magic(saddr: src, daddr: dst, len: skb->len, IPPROTO_DCCP, sum: skb->csum); |
379 | } |
380 | |
381 | void dccp_v4_send_check(struct sock *sk, struct sk_buff *skb) |
382 | { |
383 | const struct inet_sock *inet = inet_sk(sk); |
384 | struct dccp_hdr *dh = dccp_hdr(skb); |
385 | |
386 | dccp_csum_outgoing(skb); |
387 | dh->dccph_checksum = dccp_v4_csum_finish(skb, |
388 | src: inet->inet_saddr, |
389 | dst: inet->inet_daddr); |
390 | } |
391 | EXPORT_SYMBOL_GPL(dccp_v4_send_check); |
392 | |
393 | static inline u64 dccp_v4_init_sequence(const struct sk_buff *skb) |
394 | { |
395 | return secure_dccp_sequence_number(saddr: ip_hdr(skb)->daddr, |
396 | daddr: ip_hdr(skb)->saddr, |
397 | sport: dccp_hdr(skb)->dccph_dport, |
398 | dport: dccp_hdr(skb)->dccph_sport); |
399 | } |
400 | |
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 | */ |
407 | struct sock *dccp_v4_request_recv_sock(const struct sock *sk, |
408 | struct sk_buff *skb, |
409 | struct request_sock *req, |
410 | struct dst_entry *dst, |
411 | struct request_sock *req_unhash, |
412 | bool *own_req) |
413 | { |
414 | struct inet_request_sock *ireq; |
415 | struct inet_sock *newinet; |
416 | struct sock *newsk; |
417 | |
418 | if (sk_acceptq_is_full(sk)) |
419 | goto exit_overflow; |
420 | |
421 | newsk = dccp_create_openreq_child(sk, req, skb); |
422 | if (newsk == NULL) |
423 | goto exit_nonewsk; |
424 | |
425 | newinet = inet_sk(newsk); |
426 | ireq = inet_rsk(sk: req); |
427 | sk_daddr_set(sk: newsk, addr: ireq->ir_rmt_addr); |
428 | sk_rcv_saddr_set(sk: newsk, addr: ireq->ir_loc_addr); |
429 | newinet->inet_saddr = ireq->ir_loc_addr; |
430 | RCU_INIT_POINTER(newinet->inet_opt, rcu_dereference(ireq->ireq_opt)); |
431 | newinet->mc_index = inet_iif(skb); |
432 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
433 | atomic_set(v: &newinet->inet_id, i: get_random_u16()); |
434 | |
435 | if (dst == NULL && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL) |
436 | goto put_and_exit; |
437 | |
438 | sk_setup_caps(sk: newsk, dst); |
439 | |
440 | dccp_sync_mss(sk: newsk, pmtu: dst_mtu(dst)); |
441 | |
442 | if (__inet_inherit_port(sk, child: newsk) < 0) |
443 | goto put_and_exit; |
444 | *own_req = inet_ehash_nolisten(sk: newsk, osk: req_to_sk(req: req_unhash), NULL); |
445 | if (*own_req) |
446 | ireq->ireq_opt = NULL; |
447 | else |
448 | newinet->inet_opt = NULL; |
449 | return newsk; |
450 | |
451 | exit_overflow: |
452 | __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
453 | exit_nonewsk: |
454 | dst_release(dst); |
455 | exit: |
456 | __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS); |
457 | return NULL; |
458 | put_and_exit: |
459 | newinet->inet_opt = NULL; |
460 | inet_csk_prepare_forced_close(sk: newsk); |
461 | dccp_done(sk: newsk); |
462 | goto exit; |
463 | } |
464 | EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock); |
465 | |
466 | static struct dst_entry* dccp_v4_route_skb(struct net *net, struct sock *sk, |
467 | struct sk_buff *skb) |
468 | { |
469 | struct rtable *rt; |
470 | const struct iphdr *iph = ip_hdr(skb); |
471 | struct flowi4 fl4 = { |
472 | .flowi4_oif = inet_iif(skb), |
473 | .daddr = iph->saddr, |
474 | .saddr = iph->daddr, |
475 | .flowi4_tos = ip_sock_rt_tos(sk), |
476 | .flowi4_scope = ip_sock_rt_scope(sk), |
477 | .flowi4_proto = sk->sk_protocol, |
478 | .fl4_sport = dccp_hdr(skb)->dccph_dport, |
479 | .fl4_dport = dccp_hdr(skb)->dccph_sport, |
480 | }; |
481 | |
482 | security_skb_classify_flow(skb, flic: flowi4_to_flowi_common(fl4: &fl4)); |
483 | rt = ip_route_output_flow(net, flp: &fl4, sk); |
484 | if (IS_ERR(ptr: rt)) { |
485 | IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); |
486 | return NULL; |
487 | } |
488 | |
489 | return &rt->dst; |
490 | } |
491 | |
492 | static int dccp_v4_send_response(const struct sock *sk, struct request_sock *req) |
493 | { |
494 | int err = -1; |
495 | struct sk_buff *skb; |
496 | struct dst_entry *dst; |
497 | struct flowi4 fl4; |
498 | |
499 | dst = inet_csk_route_req(sk, fl4: &fl4, req); |
500 | if (dst == NULL) |
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(sk: req); |
506 | struct dccp_hdr *dh = dccp_hdr(skb); |
507 | |
508 | dh->dccph_checksum = dccp_v4_csum_finish(skb, src: ireq->ir_loc_addr, |
509 | dst: ireq->ir_rmt_addr); |
510 | rcu_read_lock(); |
511 | err = ip_build_and_send_pkt(skb, sk, saddr: ireq->ir_loc_addr, |
512 | daddr: ireq->ir_rmt_addr, |
513 | rcu_dereference(ireq->ireq_opt), |
514 | READ_ONCE(inet_sk(sk)->tos)); |
515 | rcu_read_unlock(); |
516 | err = net_xmit_eval(err); |
517 | } |
518 | |
519 | out: |
520 | dst_release(dst); |
521 | return err; |
522 | } |
523 | |
524 | static void dccp_v4_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb) |
525 | { |
526 | int err; |
527 | const struct iphdr *rxiph; |
528 | struct sk_buff *skb; |
529 | struct dst_entry *dst; |
530 | struct net *net = dev_net(dev: skb_dst(skb: rxskb)->dev); |
531 | struct dccp_v4_pernet *pn; |
532 | struct sock *ctl_sk; |
533 | |
534 | /* Never send a reset in response to a reset. */ |
535 | if (dccp_hdr(skb: rxskb)->dccph_type == DCCP_PKT_RESET) |
536 | return; |
537 | |
538 | if (skb_rtable(skb: rxskb)->rt_type != RTN_LOCAL) |
539 | return; |
540 | |
541 | pn = net_generic(net, id: dccp_v4_pernet_id); |
542 | ctl_sk = pn->v4_ctl_sk; |
543 | dst = dccp_v4_route_skb(net, sk: ctl_sk, skb: rxskb); |
544 | if (dst == NULL) |
545 | return; |
546 | |
547 | skb = dccp_ctl_make_reset(sk: ctl_sk, skb: rxskb); |
548 | if (skb == NULL) |
549 | goto out; |
550 | |
551 | rxiph = ip_hdr(skb: rxskb); |
552 | dccp_hdr(skb)->dccph_checksum = dccp_v4_csum_finish(skb, src: rxiph->saddr, |
553 | dst: rxiph->daddr); |
554 | skb_dst_set(skb, dst: dst_clone(dst)); |
555 | |
556 | local_bh_disable(); |
557 | bh_lock_sock(ctl_sk); |
558 | err = ip_build_and_send_pkt(skb, sk: ctl_sk, |
559 | saddr: rxiph->daddr, daddr: rxiph->saddr, NULL, |
560 | inet_sk(ctl_sk)->tos); |
561 | bh_unlock_sock(ctl_sk); |
562 | |
563 | if (net_xmit_eval(err) == 0) { |
564 | __DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
565 | __DCCP_INC_STATS(DCCP_MIB_OUTRSTS); |
566 | } |
567 | local_bh_enable(); |
568 | out: |
569 | dst_release(dst); |
570 | } |
571 | |
572 | static void dccp_v4_reqsk_destructor(struct request_sock *req) |
573 | { |
574 | dccp_feat_list_purge(fn_list: &dccp_rsk(req)->dreq_featneg); |
575 | kfree(rcu_dereference_protected(inet_rsk(req)->ireq_opt, 1)); |
576 | } |
577 | |
578 | void dccp_syn_ack_timeout(const struct request_sock *req) |
579 | { |
580 | } |
581 | EXPORT_SYMBOL(dccp_syn_ack_timeout); |
582 | |
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, |
590 | .syn_ack_timeout = dccp_syn_ack_timeout, |
591 | }; |
592 | |
593 | int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
594 | { |
595 | struct inet_request_sock *ireq; |
596 | struct request_sock *req; |
597 | struct dccp_request_sock *dreq; |
598 | const __be32 service = dccp_hdr_request(skb)->dccph_req_service; |
599 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
600 | |
601 | /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */ |
602 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
603 | return 0; /* discard, don't send a reset here */ |
604 | |
605 | if (dccp_bad_service_code(sk, service)) { |
606 | dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; |
607 | goto drop; |
608 | } |
609 | /* |
610 | * TW buckets are converted to open requests without |
611 | * limitations, they conserve resources and peer is |
612 | * evidently real one. |
613 | */ |
614 | dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; |
615 | if (inet_csk_reqsk_queue_is_full(sk)) |
616 | goto drop; |
617 | |
618 | if (sk_acceptq_is_full(sk)) |
619 | goto drop; |
620 | |
621 | req = inet_reqsk_alloc(ops: &dccp_request_sock_ops, sk_listener: sk, attach_listener: true); |
622 | if (req == NULL) |
623 | goto drop; |
624 | |
625 | if (dccp_reqsk_init(rq: req, dccp_sk(sk), skb)) |
626 | goto drop_and_free; |
627 | |
628 | dreq = dccp_rsk(req); |
629 | if (dccp_parse_options(sk, dreq, skb)) |
630 | goto drop_and_free; |
631 | |
632 | ireq = inet_rsk(sk: req); |
633 | sk_rcv_saddr_set(sk: req_to_sk(req), addr: ip_hdr(skb)->daddr); |
634 | sk_daddr_set(sk: req_to_sk(req), addr: ip_hdr(skb)->saddr); |
635 | ireq->ir_mark = inet_request_mark(sk, skb); |
636 | ireq->ireq_family = AF_INET; |
637 | ireq->ir_iif = READ_ONCE(sk->sk_bound_dev_if); |
638 | |
639 | if (security_inet_conn_request(sk, skb, req)) |
640 | goto drop_and_free; |
641 | |
642 | /* |
643 | * Step 3: Process LISTEN state |
644 | * |
645 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie |
646 | * |
647 | * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child(). |
648 | */ |
649 | dreq->dreq_isr = dcb->dccpd_seq; |
650 | dreq->dreq_gsr = dreq->dreq_isr; |
651 | dreq->dreq_iss = dccp_v4_init_sequence(skb); |
652 | dreq->dreq_gss = dreq->dreq_iss; |
653 | dreq->dreq_service = service; |
654 | |
655 | if (dccp_v4_send_response(sk, req)) |
656 | goto drop_and_free; |
657 | |
658 | inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); |
659 | reqsk_put(req); |
660 | return 0; |
661 | |
662 | drop_and_free: |
663 | reqsk_free(req); |
664 | drop: |
665 | __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS); |
666 | return -1; |
667 | } |
668 | EXPORT_SYMBOL_GPL(dccp_v4_conn_request); |
669 | |
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, len: skb->len)) |
676 | goto reset; |
677 | return 0; |
678 | } |
679 | |
680 | /* |
681 | * Step 3: Process LISTEN state |
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 |
699 | * |
700 | * NOTE: the check for the packet types is done in |
701 | * dccp_rcv_state_process |
702 | */ |
703 | |
704 | if (dccp_rcv_state_process(sk, skb, dh, len: skb->len)) |
705 | goto reset; |
706 | return 0; |
707 | |
708 | reset: |
709 | dccp_v4_ctl_send_reset(sk, rxskb: skb); |
710 | kfree_skb(skb); |
711 | return 0; |
712 | } |
713 | EXPORT_SYMBOL_GPL(dccp_v4_do_rcv); |
714 | |
715 | /** |
716 | * dccp_invalid_packet - check for malformed packets |
717 | * @skb: Packet to validate |
718 | * |
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 | */ |
722 | int dccp_invalid_packet(struct sk_buff *skb) |
723 | { |
724 | const struct dccp_hdr *dh; |
725 | unsigned int cscov; |
726 | u8 dccph_doff; |
727 | |
728 | if (skb->pkt_type != PACKET_HOST) |
729 | return 1; |
730 | |
731 | /* If the packet is shorter than 12 bytes, drop packet and return */ |
732 | if (!pskb_may_pull(skb, len: sizeof(struct dccp_hdr))) { |
733 | DCCP_WARN("pskb_may_pull failed\n" ); |
734 | return 1; |
735 | } |
736 | |
737 | dh = dccp_hdr(skb); |
738 | |
739 | /* If P.type is not understood, drop packet and return */ |
740 | if (dh->dccph_type >= DCCP_PKT_INVALID) { |
741 | DCCP_WARN("invalid packet type\n" ); |
742 | return 1; |
743 | } |
744 | |
745 | /* |
746 | * If P.Data Offset is too small for packet type, drop packet and return |
747 | */ |
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); |
751 | return 1; |
752 | } |
753 | /* |
754 | * If P.Data Offset is too large for packet, drop packet and return |
755 | */ |
756 | if (!pskb_may_pull(skb, len: dccph_doff * sizeof(u32))) { |
757 | DCCP_WARN("P.Data Offset(%u) too large\n" , dccph_doff); |
758 | return 1; |
759 | } |
760 | dh = dccp_hdr(skb); |
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 | */ |
765 | if ((dh->dccph_type < DCCP_PKT_DATA || |
766 | dh->dccph_type > DCCP_PKT_DATAACK) && dh->dccph_x == 0) { |
767 | DCCP_WARN("P.type (%s) not Data || [Data]Ack, while P.X == 0\n" , |
768 | dccp_packet_name(dh->dccph_type)); |
769 | return 1; |
770 | } |
771 | |
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) { |
778 | DCCP_WARN("P.CsCov %u exceeds packet length %d\n" , |
779 | dh->dccph_cscov, skb->len); |
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, offset: 0, len: cscov, csum: 0); |
786 | |
787 | return 0; |
788 | } |
789 | EXPORT_SYMBOL_GPL(dccp_invalid_packet); |
790 | |
791 | /* this is called when real data arrives */ |
792 | static int dccp_v4_rcv(struct sk_buff *skb) |
793 | { |
794 | const struct dccp_hdr *dh; |
795 | const struct iphdr *iph; |
796 | bool refcounted; |
797 | struct sock *sk; |
798 | int min_cov; |
799 | |
800 | /* Step 1: Check header basics */ |
801 | |
802 | if (dccp_invalid_packet(skb)) |
803 | goto discard_it; |
804 | |
805 | iph = ip_hdr(skb); |
806 | /* Step 1: If header checksum is incorrect, drop packet and return */ |
807 | if (dccp_v4_csum_finish(skb, src: iph->saddr, dst: iph->daddr)) { |
808 | DCCP_WARN("dropped packet with invalid checksum\n" ); |
809 | goto discard_it; |
810 | } |
811 | |
812 | dh = dccp_hdr(skb); |
813 | |
814 | DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh); |
815 | DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type; |
816 | |
817 | dccp_pr_debug("%8.8s src=%pI4@%-5d dst=%pI4@%-5d seq=%llu" , |
818 | dccp_packet_name(dh->dccph_type), |
819 | &iph->saddr, ntohs(dh->dccph_sport), |
820 | &iph->daddr, ntohs(dh->dccph_dport), |
821 | (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq); |
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); |
828 | dccp_pr_debug_cat(", ack=%llu\n" , (unsigned long long) |
829 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
830 | } |
831 | |
832 | lookup: |
833 | sk = __inet_lookup_skb(hashinfo: &dccp_hashinfo, skb, doff: __dccp_hdr_len(dh), |
834 | sport: dh->dccph_sport, dport: dh->dccph_dport, sdif: 0, refcounted: &refcounted); |
835 | if (!sk) { |
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 | |
841 | /* |
842 | * Step 2: |
843 | * ... or S.state == TIMEWAIT, |
844 | * Generate Reset(No Connection) unless P.type == Reset |
845 | * Drop packet and return |
846 | */ |
847 | if (sk->sk_state == DCCP_TIME_WAIT) { |
848 | dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n" ); |
849 | inet_twsk_put(tw: inet_twsk(sk)); |
850 | goto no_dccp_socket; |
851 | } |
852 | |
853 | if (sk->sk_state == DCCP_NEW_SYN_RECV) { |
854 | struct request_sock *req = inet_reqsk(sk); |
855 | struct sock *nsk; |
856 | |
857 | sk = req->rsk_listener; |
858 | if (unlikely(sk->sk_state != DCCP_LISTEN)) { |
859 | inet_csk_reqsk_queue_drop_and_put(sk, req); |
860 | goto lookup; |
861 | } |
862 | sock_hold(sk); |
863 | refcounted = true; |
864 | nsk = dccp_check_req(sk, skb, req); |
865 | if (!nsk) { |
866 | reqsk_put(req); |
867 | goto discard_and_relse; |
868 | } |
869 | if (nsk == sk) { |
870 | reqsk_put(req); |
871 | } else if (dccp_child_process(parent: sk, child: nsk, skb)) { |
872 | dccp_v4_ctl_send_reset(sk, rxskb: skb); |
873 | goto discard_and_relse; |
874 | } else { |
875 | sock_put(sk); |
876 | return 0; |
877 | } |
878 | } |
879 | /* |
880 | * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage |
881 | * o if MinCsCov = 0, only packets with CsCov = 0 are accepted |
882 | * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov |
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 | |
894 | if (!xfrm4_policy_check(sk, dir: XFRM_POLICY_IN, skb)) |
895 | goto discard_and_relse; |
896 | nf_reset_ct(skb); |
897 | |
898 | return __sk_receive_skb(sk, skb, nested: 1, trim_cap: dh->dccph_doff * 4, refcounted); |
899 | |
900 | no_dccp_socket: |
901 | if (!xfrm4_policy_check(NULL, dir: XFRM_POLICY_IN, skb)) |
902 | goto discard_it; |
903 | /* |
904 | * Step 2: |
905 | * If no socket ... |
906 | * Generate Reset(No Connection) unless P.type == Reset |
907 | * Drop packet and return |
908 | */ |
909 | if (dh->dccph_type != DCCP_PKT_RESET) { |
910 | DCCP_SKB_CB(skb)->dccpd_reset_code = |
911 | DCCP_RESET_CODE_NO_CONNECTION; |
912 | dccp_v4_ctl_send_reset(sk, rxskb: skb); |
913 | } |
914 | |
915 | discard_it: |
916 | kfree_skb(skb); |
917 | return 0; |
918 | |
919 | discard_and_relse: |
920 | if (refcounted) |
921 | sock_put(sk); |
922 | goto discard_it; |
923 | } |
924 | |
925 | static const struct inet_connection_sock_af_ops dccp_ipv4_af_ops = { |
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), |
936 | }; |
937 | |
938 | static int dccp_v4_init_sock(struct sock *sk) |
939 | { |
940 | static __u8 dccp_v4_ctl_sock_initialized; |
941 | int err = dccp_init_sock(sk, ctl_sock_initialized: dccp_v4_ctl_sock_initialized); |
942 | |
943 | if (err == 0) { |
944 | if (unlikely(!dccp_v4_ctl_sock_initialized)) |
945 | dccp_v4_ctl_sock_initialized = 1; |
946 | inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops; |
947 | } |
948 | |
949 | return err; |
950 | } |
951 | |
952 | static struct timewait_sock_ops dccp_timewait_sock_ops = { |
953 | .twsk_obj_size = sizeof(struct inet_timewait_sock), |
954 | }; |
955 | |
956 | static struct proto dccp_v4_prot = { |
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, |
969 | .hash = inet_hash, |
970 | .unhash = inet_unhash, |
971 | .accept = inet_csk_accept, |
972 | .get_port = inet_csk_get_port, |
973 | .shutdown = dccp_shutdown, |
974 | .destroy = dccp_destroy_sock, |
975 | .orphan_count = &dccp_orphan_count, |
976 | .max_header = MAX_DCCP_HEADER, |
977 | .obj_size = sizeof(struct dccp_sock), |
978 | .slab_flags = SLAB_TYPESAFE_BY_RCU, |
979 | .rsk_prot = &dccp_request_sock_ops, |
980 | .twsk_prot = &dccp_timewait_sock_ops, |
981 | .h.hashinfo = &dccp_hashinfo, |
982 | }; |
983 | |
984 | static const struct net_protocol dccp_v4_protocol = { |
985 | .handler = dccp_v4_rcv, |
986 | .err_handler = dccp_v4_err, |
987 | .no_policy = 1, |
988 | .icmp_strict_tag_validation = 1, |
989 | }; |
990 | |
991 | static const struct proto_ops inet_dccp_ops = { |
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, |
1000 | /* FIXME: work on tcp_poll to rename it to inet_csk_poll */ |
1001 | .poll = dccp_poll, |
1002 | .ioctl = inet_ioctl, |
1003 | .gettstamp = sock_gettstamp, |
1004 | /* FIXME: work on inet_listen to rename it to sock_common_listen */ |
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, |
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, |
1019 | .flags = INET_PROTOSW_ICSK, |
1020 | }; |
1021 | |
1022 | static int __net_init dccp_v4_init_net(struct net *net) |
1023 | { |
1024 | struct dccp_v4_pernet *pn = net_generic(net, id: dccp_v4_pernet_id); |
1025 | |
1026 | if (dccp_hashinfo.bhash == NULL) |
1027 | return -ESOCKTNOSUPPORT; |
1028 | |
1029 | return inet_ctl_sock_create(sk: &pn->v4_ctl_sk, PF_INET, |
1030 | type: SOCK_DCCP, IPPROTO_DCCP, net); |
1031 | } |
1032 | |
1033 | static void __net_exit dccp_v4_exit_net(struct net *net) |
1034 | { |
1035 | struct dccp_v4_pernet *pn = net_generic(net, id: dccp_v4_pernet_id); |
1036 | |
1037 | inet_ctl_sock_destroy(sk: pn->v4_ctl_sk); |
1038 | } |
1039 | |
1040 | static void __net_exit dccp_v4_exit_batch(struct list_head *net_exit_list) |
1041 | { |
1042 | inet_twsk_purge(hashinfo: &dccp_hashinfo, AF_INET); |
1043 | } |
1044 | |
1045 | static struct pernet_operations dccp_v4_ops = { |
1046 | .init = dccp_v4_init_net, |
1047 | .exit = dccp_v4_exit_net, |
1048 | .exit_batch = dccp_v4_exit_batch, |
1049 | .id = &dccp_v4_pernet_id, |
1050 | .size = sizeof(struct dccp_v4_pernet), |
1051 | }; |
1052 | |
1053 | static int __init dccp_v4_init(void) |
1054 | { |
1055 | int err = proto_register(prot: &dccp_v4_prot, alloc_slab: 1); |
1056 | |
1057 | if (err) |
1058 | goto out; |
1059 | |
1060 | inet_register_protosw(p: &dccp_v4_protosw); |
1061 | |
1062 | err = register_pernet_subsys(&dccp_v4_ops); |
1063 | if (err) |
1064 | goto out_destroy_ctl_sock; |
1065 | |
1066 | err = inet_add_protocol(prot: &dccp_v4_protocol, IPPROTO_DCCP); |
1067 | if (err) |
1068 | goto out_proto_unregister; |
1069 | |
1070 | out: |
1071 | return err; |
1072 | out_proto_unregister: |
1073 | unregister_pernet_subsys(&dccp_v4_ops); |
1074 | out_destroy_ctl_sock: |
1075 | inet_unregister_protosw(p: &dccp_v4_protosw); |
1076 | proto_unregister(prot: &dccp_v4_prot); |
1077 | goto out; |
1078 | } |
1079 | |
1080 | static void __exit dccp_v4_exit(void) |
1081 | { |
1082 | inet_del_protocol(prot: &dccp_v4_protocol, IPPROTO_DCCP); |
1083 | unregister_pernet_subsys(&dccp_v4_ops); |
1084 | inet_unregister_protosw(p: &dccp_v4_protosw); |
1085 | proto_unregister(prot: &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 | */ |
1096 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 33, 6); |
1097 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 0, 6); |
1098 | MODULE_LICENSE("GPL" ); |
1099 | MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>" ); |
1100 | MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol" ); |
1101 | |