nfsd4: typo logical vs bitwise negate for want_mask
[linux-btrfs-devel.git] / net / dccp / ipv6.c
blobb74f76117dcf6fde6e660cafe7334d22225bf40f
1 /*
2 * DCCP over IPv6
3 * Linux INET6 implementation
5 * Based on net/dccp6/ipv6.c
7 * Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
15 #include <linux/module.h>
16 #include <linux/random.h>
17 #include <linux/slab.h>
18 #include <linux/xfrm.h>
20 #include <net/addrconf.h>
21 #include <net/inet_common.h>
22 #include <net/inet_hashtables.h>
23 #include <net/inet_sock.h>
24 #include <net/inet6_connection_sock.h>
25 #include <net/inet6_hashtables.h>
26 #include <net/ip6_route.h>
27 #include <net/ipv6.h>
28 #include <net/protocol.h>
29 #include <net/transp_v6.h>
30 #include <net/ip6_checksum.h>
31 #include <net/xfrm.h>
32 #include <net/secure_seq.h>
34 #include "dccp.h"
35 #include "ipv6.h"
36 #include "feat.h"
38 /* The per-net dccp.v6_ctl_sk is used for sending RSTs and ACKs */
40 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped;
41 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops;
43 static void dccp_v6_hash(struct sock *sk)
45 if (sk->sk_state != DCCP_CLOSED) {
46 if (inet_csk(sk)->icsk_af_ops == &dccp_ipv6_mapped) {
47 inet_hash(sk);
48 return;
50 local_bh_disable();
51 __inet6_hash(sk, NULL);
52 local_bh_enable();
56 /* add pseudo-header to DCCP checksum stored in skb->csum */
57 static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb,
58 const struct in6_addr *saddr,
59 const struct in6_addr *daddr)
61 return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum);
64 static inline void dccp_v6_send_check(struct sock *sk, struct sk_buff *skb)
66 struct ipv6_pinfo *np = inet6_sk(sk);
67 struct dccp_hdr *dh = dccp_hdr(skb);
69 dccp_csum_outgoing(skb);
70 dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &np->daddr);
73 static inline __u64 dccp_v6_init_sequence(struct sk_buff *skb)
75 return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
76 ipv6_hdr(skb)->saddr.s6_addr32,
77 dccp_hdr(skb)->dccph_dport,
78 dccp_hdr(skb)->dccph_sport );
82 static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
83 u8 type, u8 code, int offset, __be32 info)
85 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
86 const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
87 struct dccp_sock *dp;
88 struct ipv6_pinfo *np;
89 struct sock *sk;
90 int err;
91 __u64 seq;
92 struct net *net = dev_net(skb->dev);
94 if (skb->len < offset + sizeof(*dh) ||
95 skb->len < offset + __dccp_basic_hdr_len(dh)) {
96 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
97 ICMP6_MIB_INERRORS);
98 return;
101 sk = inet6_lookup(net, &dccp_hashinfo,
102 &hdr->daddr, dh->dccph_dport,
103 &hdr->saddr, dh->dccph_sport, inet6_iif(skb));
105 if (sk == NULL) {
106 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
107 ICMP6_MIB_INERRORS);
108 return;
111 if (sk->sk_state == DCCP_TIME_WAIT) {
112 inet_twsk_put(inet_twsk(sk));
113 return;
116 bh_lock_sock(sk);
117 if (sock_owned_by_user(sk))
118 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
120 if (sk->sk_state == DCCP_CLOSED)
121 goto out;
123 dp = dccp_sk(sk);
124 seq = dccp_hdr_seq(dh);
125 if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) &&
126 !between48(seq, dp->dccps_awl, dp->dccps_awh)) {
127 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
128 goto out;
131 np = inet6_sk(sk);
133 if (type == ICMPV6_PKT_TOOBIG) {
134 struct dst_entry *dst = NULL;
136 if (sock_owned_by_user(sk))
137 goto out;
138 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
139 goto out;
141 /* icmp should have updated the destination cache entry */
142 dst = __sk_dst_check(sk, np->dst_cookie);
143 if (dst == NULL) {
144 struct inet_sock *inet = inet_sk(sk);
145 struct flowi6 fl6;
147 /* BUGGG_FUTURE: Again, it is not clear how
148 to handle rthdr case. Ignore this complexity
149 for now.
151 memset(&fl6, 0, sizeof(fl6));
152 fl6.flowi6_proto = IPPROTO_DCCP;
153 ipv6_addr_copy(&fl6.daddr, &np->daddr);
154 ipv6_addr_copy(&fl6.saddr, &np->saddr);
155 fl6.flowi6_oif = sk->sk_bound_dev_if;
156 fl6.fl6_dport = inet->inet_dport;
157 fl6.fl6_sport = inet->inet_sport;
158 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
160 dst = ip6_dst_lookup_flow(sk, &fl6, NULL, false);
161 if (IS_ERR(dst)) {
162 sk->sk_err_soft = -PTR_ERR(dst);
163 goto out;
165 } else
166 dst_hold(dst);
168 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
169 dccp_sync_mss(sk, dst_mtu(dst));
170 } /* else let the usual retransmit timer handle it */
171 dst_release(dst);
172 goto out;
175 icmpv6_err_convert(type, code, &err);
177 /* Might be for an request_sock */
178 switch (sk->sk_state) {
179 struct request_sock *req, **prev;
180 case DCCP_LISTEN:
181 if (sock_owned_by_user(sk))
182 goto out;
184 req = inet6_csk_search_req(sk, &prev, dh->dccph_dport,
185 &hdr->daddr, &hdr->saddr,
186 inet6_iif(skb));
187 if (req == NULL)
188 goto out;
191 * ICMPs are not backlogged, hence we cannot get an established
192 * socket here.
194 WARN_ON(req->sk != NULL);
196 if (seq != dccp_rsk(req)->dreq_iss) {
197 NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
198 goto out;
201 inet_csk_reqsk_queue_drop(sk, req, prev);
202 goto out;
204 case DCCP_REQUESTING:
205 case DCCP_RESPOND: /* Cannot happen.
206 It can, it SYNs are crossed. --ANK */
207 if (!sock_owned_by_user(sk)) {
208 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
209 sk->sk_err = err;
211 * Wake people up to see the error
212 * (see connect in sock.c)
214 sk->sk_error_report(sk);
215 dccp_done(sk);
216 } else
217 sk->sk_err_soft = err;
218 goto out;
221 if (!sock_owned_by_user(sk) && np->recverr) {
222 sk->sk_err = err;
223 sk->sk_error_report(sk);
224 } else
225 sk->sk_err_soft = err;
227 out:
228 bh_unlock_sock(sk);
229 sock_put(sk);
233 static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
234 struct request_values *rv_unused)
236 struct inet6_request_sock *ireq6 = inet6_rsk(req);
237 struct ipv6_pinfo *np = inet6_sk(sk);
238 struct sk_buff *skb;
239 struct ipv6_txoptions *opt = NULL;
240 struct in6_addr *final_p, final;
241 struct flowi6 fl6;
242 int err = -1;
243 struct dst_entry *dst;
245 memset(&fl6, 0, sizeof(fl6));
246 fl6.flowi6_proto = IPPROTO_DCCP;
247 ipv6_addr_copy(&fl6.daddr, &ireq6->rmt_addr);
248 ipv6_addr_copy(&fl6.saddr, &ireq6->loc_addr);
249 fl6.flowlabel = 0;
250 fl6.flowi6_oif = ireq6->iif;
251 fl6.fl6_dport = inet_rsk(req)->rmt_port;
252 fl6.fl6_sport = inet_rsk(req)->loc_port;
253 security_req_classify_flow(req, flowi6_to_flowi(&fl6));
255 opt = np->opt;
257 final_p = fl6_update_dst(&fl6, opt, &final);
259 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
260 if (IS_ERR(dst)) {
261 err = PTR_ERR(dst);
262 dst = NULL;
263 goto done;
266 skb = dccp_make_response(sk, dst, req);
267 if (skb != NULL) {
268 struct dccp_hdr *dh = dccp_hdr(skb);
270 dh->dccph_checksum = dccp_v6_csum_finish(skb,
271 &ireq6->loc_addr,
272 &ireq6->rmt_addr);
273 ipv6_addr_copy(&fl6.daddr, &ireq6->rmt_addr);
274 err = ip6_xmit(sk, skb, &fl6, opt);
275 err = net_xmit_eval(err);
278 done:
279 if (opt != NULL && opt != np->opt)
280 sock_kfree_s(sk, opt, opt->tot_len);
281 dst_release(dst);
282 return err;
285 static void dccp_v6_reqsk_destructor(struct request_sock *req)
287 dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
288 if (inet6_rsk(req)->pktopts != NULL)
289 kfree_skb(inet6_rsk(req)->pktopts);
292 static void dccp_v6_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
294 const struct ipv6hdr *rxip6h;
295 struct sk_buff *skb;
296 struct flowi6 fl6;
297 struct net *net = dev_net(skb_dst(rxskb)->dev);
298 struct sock *ctl_sk = net->dccp.v6_ctl_sk;
299 struct dst_entry *dst;
301 if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
302 return;
304 if (!ipv6_unicast_destination(rxskb))
305 return;
307 skb = dccp_ctl_make_reset(ctl_sk, rxskb);
308 if (skb == NULL)
309 return;
311 rxip6h = ipv6_hdr(rxskb);
312 dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
313 &rxip6h->daddr);
315 memset(&fl6, 0, sizeof(fl6));
316 ipv6_addr_copy(&fl6.daddr, &rxip6h->saddr);
317 ipv6_addr_copy(&fl6.saddr, &rxip6h->daddr);
319 fl6.flowi6_proto = IPPROTO_DCCP;
320 fl6.flowi6_oif = inet6_iif(rxskb);
321 fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
322 fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
323 security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6));
325 /* sk = NULL, but it is safe for now. RST socket required. */
326 dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL, false);
327 if (!IS_ERR(dst)) {
328 skb_dst_set(skb, dst);
329 ip6_xmit(ctl_sk, skb, &fl6, NULL);
330 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
331 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
332 return;
335 kfree_skb(skb);
338 static struct request_sock_ops dccp6_request_sock_ops = {
339 .family = AF_INET6,
340 .obj_size = sizeof(struct dccp6_request_sock),
341 .rtx_syn_ack = dccp_v6_send_response,
342 .send_ack = dccp_reqsk_send_ack,
343 .destructor = dccp_v6_reqsk_destructor,
344 .send_reset = dccp_v6_ctl_send_reset,
347 static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
349 const struct dccp_hdr *dh = dccp_hdr(skb);
350 const struct ipv6hdr *iph = ipv6_hdr(skb);
351 struct sock *nsk;
352 struct request_sock **prev;
353 /* Find possible connection requests. */
354 struct request_sock *req = inet6_csk_search_req(sk, &prev,
355 dh->dccph_sport,
356 &iph->saddr,
357 &iph->daddr,
358 inet6_iif(skb));
359 if (req != NULL)
360 return dccp_check_req(sk, skb, req, prev);
362 nsk = __inet6_lookup_established(sock_net(sk), &dccp_hashinfo,
363 &iph->saddr, dh->dccph_sport,
364 &iph->daddr, ntohs(dh->dccph_dport),
365 inet6_iif(skb));
366 if (nsk != NULL) {
367 if (nsk->sk_state != DCCP_TIME_WAIT) {
368 bh_lock_sock(nsk);
369 return nsk;
371 inet_twsk_put(inet_twsk(nsk));
372 return NULL;
375 return sk;
378 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
380 struct request_sock *req;
381 struct dccp_request_sock *dreq;
382 struct inet6_request_sock *ireq6;
383 struct ipv6_pinfo *np = inet6_sk(sk);
384 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
385 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
387 if (skb->protocol == htons(ETH_P_IP))
388 return dccp_v4_conn_request(sk, skb);
390 if (!ipv6_unicast_destination(skb))
391 return 0; /* discard, don't send a reset here */
393 if (dccp_bad_service_code(sk, service)) {
394 dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
395 goto drop;
398 * There are no SYN attacks on IPv6, yet...
400 dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
401 if (inet_csk_reqsk_queue_is_full(sk))
402 goto drop;
404 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
405 goto drop;
407 req = inet6_reqsk_alloc(&dccp6_request_sock_ops);
408 if (req == NULL)
409 goto drop;
411 if (dccp_reqsk_init(req, dccp_sk(sk), skb))
412 goto drop_and_free;
414 dreq = dccp_rsk(req);
415 if (dccp_parse_options(sk, dreq, skb))
416 goto drop_and_free;
418 if (security_inet_conn_request(sk, skb, req))
419 goto drop_and_free;
421 ireq6 = inet6_rsk(req);
422 ipv6_addr_copy(&ireq6->rmt_addr, &ipv6_hdr(skb)->saddr);
423 ipv6_addr_copy(&ireq6->loc_addr, &ipv6_hdr(skb)->daddr);
425 if (ipv6_opt_accepted(sk, skb) ||
426 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
427 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
428 atomic_inc(&skb->users);
429 ireq6->pktopts = skb;
431 ireq6->iif = sk->sk_bound_dev_if;
433 /* So that link locals have meaning */
434 if (!sk->sk_bound_dev_if &&
435 ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL)
436 ireq6->iif = inet6_iif(skb);
439 * Step 3: Process LISTEN state
441 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
443 * In fact we defer setting S.GSR, S.SWL, S.SWH to
444 * dccp_create_openreq_child.
446 dreq->dreq_isr = dcb->dccpd_seq;
447 dreq->dreq_iss = dccp_v6_init_sequence(skb);
448 dreq->dreq_service = service;
450 if (dccp_v6_send_response(sk, req, NULL))
451 goto drop_and_free;
453 inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
454 return 0;
456 drop_and_free:
457 reqsk_free(req);
458 drop:
459 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
460 return -1;
463 static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
464 struct sk_buff *skb,
465 struct request_sock *req,
466 struct dst_entry *dst)
468 struct inet6_request_sock *ireq6 = inet6_rsk(req);
469 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
470 struct inet_sock *newinet;
471 struct dccp6_sock *newdp6;
472 struct sock *newsk;
473 struct ipv6_txoptions *opt;
475 if (skb->protocol == htons(ETH_P_IP)) {
477 * v6 mapped
479 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
480 if (newsk == NULL)
481 return NULL;
483 newdp6 = (struct dccp6_sock *)newsk;
484 newinet = inet_sk(newsk);
485 newinet->pinet6 = &newdp6->inet6;
486 newnp = inet6_sk(newsk);
488 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
490 ipv6_addr_set_v4mapped(newinet->inet_daddr, &newnp->daddr);
492 ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr);
494 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
496 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
497 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
498 newnp->pktoptions = NULL;
499 newnp->opt = NULL;
500 newnp->mcast_oif = inet6_iif(skb);
501 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
504 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
505 * here, dccp_create_openreq_child now does this for us, see the comment in
506 * that function for the gory details. -acme
509 /* It is tricky place. Until this moment IPv4 tcp
510 worked with IPv6 icsk.icsk_af_ops.
511 Sync it now.
513 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
515 return newsk;
518 opt = np->opt;
520 if (sk_acceptq_is_full(sk))
521 goto out_overflow;
523 if (dst == NULL) {
524 struct in6_addr *final_p, final;
525 struct flowi6 fl6;
527 memset(&fl6, 0, sizeof(fl6));
528 fl6.flowi6_proto = IPPROTO_DCCP;
529 ipv6_addr_copy(&fl6.daddr, &ireq6->rmt_addr);
530 final_p = fl6_update_dst(&fl6, opt, &final);
531 ipv6_addr_copy(&fl6.saddr, &ireq6->loc_addr);
532 fl6.flowi6_oif = sk->sk_bound_dev_if;
533 fl6.fl6_dport = inet_rsk(req)->rmt_port;
534 fl6.fl6_sport = inet_rsk(req)->loc_port;
535 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
537 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
538 if (IS_ERR(dst))
539 goto out;
542 newsk = dccp_create_openreq_child(sk, req, skb);
543 if (newsk == NULL)
544 goto out_nonewsk;
547 * No need to charge this sock to the relevant IPv6 refcnt debug socks
548 * count here, dccp_create_openreq_child now does this for us, see the
549 * comment in that function for the gory details. -acme
552 __ip6_dst_store(newsk, dst, NULL, NULL);
553 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
554 NETIF_F_TSO);
555 newdp6 = (struct dccp6_sock *)newsk;
556 newinet = inet_sk(newsk);
557 newinet->pinet6 = &newdp6->inet6;
558 newnp = inet6_sk(newsk);
560 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
562 ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr);
563 ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr);
564 ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr);
565 newsk->sk_bound_dev_if = ireq6->iif;
567 /* Now IPv6 options...
569 First: no IPv4 options.
571 newinet->inet_opt = NULL;
573 /* Clone RX bits */
574 newnp->rxopt.all = np->rxopt.all;
576 /* Clone pktoptions received with SYN */
577 newnp->pktoptions = NULL;
578 if (ireq6->pktopts != NULL) {
579 newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC);
580 kfree_skb(ireq6->pktopts);
581 ireq6->pktopts = NULL;
582 if (newnp->pktoptions)
583 skb_set_owner_r(newnp->pktoptions, newsk);
585 newnp->opt = NULL;
586 newnp->mcast_oif = inet6_iif(skb);
587 newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
590 * Clone native IPv6 options from listening socket (if any)
592 * Yes, keeping reference count would be much more clever, but we make
593 * one more one thing there: reattach optmem to newsk.
595 if (opt != NULL) {
596 newnp->opt = ipv6_dup_options(newsk, opt);
597 if (opt != np->opt)
598 sock_kfree_s(sk, opt, opt->tot_len);
601 inet_csk(newsk)->icsk_ext_hdr_len = 0;
602 if (newnp->opt != NULL)
603 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
604 newnp->opt->opt_flen);
606 dccp_sync_mss(newsk, dst_mtu(dst));
608 newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
609 newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
611 if (__inet_inherit_port(sk, newsk) < 0) {
612 sock_put(newsk);
613 goto out;
615 __inet6_hash(newsk, NULL);
617 return newsk;
619 out_overflow:
620 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
621 out_nonewsk:
622 dst_release(dst);
623 out:
624 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
625 if (opt != NULL && opt != np->opt)
626 sock_kfree_s(sk, opt, opt->tot_len);
627 return NULL;
630 /* The socket must have it's spinlock held when we get
631 * here.
633 * We have a potential double-lock case here, so even when
634 * doing backlog processing we use the BH locking scheme.
635 * This is because we cannot sleep with the original spinlock
636 * held.
638 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
640 struct ipv6_pinfo *np = inet6_sk(sk);
641 struct sk_buff *opt_skb = NULL;
643 /* Imagine: socket is IPv6. IPv4 packet arrives,
644 goes to IPv4 receive handler and backlogged.
645 From backlog it always goes here. Kerboom...
646 Fortunately, dccp_rcv_established and rcv_established
647 handle them correctly, but it is not case with
648 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
651 if (skb->protocol == htons(ETH_P_IP))
652 return dccp_v4_do_rcv(sk, skb);
654 if (sk_filter(sk, skb))
655 goto discard;
658 * socket locking is here for SMP purposes as backlog rcv is currently
659 * called with bh processing disabled.
662 /* Do Stevens' IPV6_PKTOPTIONS.
664 Yes, guys, it is the only place in our code, where we
665 may make it not affecting IPv4.
666 The rest of code is protocol independent,
667 and I do not like idea to uglify IPv4.
669 Actually, all the idea behind IPV6_PKTOPTIONS
670 looks not very well thought. For now we latch
671 options, received in the last packet, enqueued
672 by tcp. Feel free to propose better solution.
673 --ANK (980728)
675 if (np->rxopt.all)
677 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
678 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
680 opt_skb = skb_clone(skb, GFP_ATOMIC);
682 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
683 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
684 goto reset;
685 if (opt_skb) {
686 /* XXX This is where we would goto ipv6_pktoptions. */
687 __kfree_skb(opt_skb);
689 return 0;
693 * Step 3: Process LISTEN state
694 * If S.state == LISTEN,
695 * If P.type == Request or P contains a valid Init Cookie option,
696 * (* Must scan the packet's options to check for Init
697 * Cookies. Only Init Cookies are processed here,
698 * however; other options are processed in Step 8. This
699 * scan need only be performed if the endpoint uses Init
700 * Cookies *)
701 * (* Generate a new socket and switch to that socket *)
702 * Set S := new socket for this port pair
703 * S.state = RESPOND
704 * Choose S.ISS (initial seqno) or set from Init Cookies
705 * Initialize S.GAR := S.ISS
706 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
707 * Continue with S.state == RESPOND
708 * (* A Response packet will be generated in Step 11 *)
709 * Otherwise,
710 * Generate Reset(No Connection) unless P.type == Reset
711 * Drop packet and return
713 * NOTE: the check for the packet types is done in
714 * dccp_rcv_state_process
716 if (sk->sk_state == DCCP_LISTEN) {
717 struct sock *nsk = dccp_v6_hnd_req(sk, skb);
719 if (nsk == NULL)
720 goto discard;
722 * Queue it on the new socket if the new socket is active,
723 * otherwise we just shortcircuit this and continue with
724 * the new socket..
726 if (nsk != sk) {
727 if (dccp_child_process(sk, nsk, skb))
728 goto reset;
729 if (opt_skb != NULL)
730 __kfree_skb(opt_skb);
731 return 0;
735 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
736 goto reset;
737 if (opt_skb) {
738 /* XXX This is where we would goto ipv6_pktoptions. */
739 __kfree_skb(opt_skb);
741 return 0;
743 reset:
744 dccp_v6_ctl_send_reset(sk, skb);
745 discard:
746 if (opt_skb != NULL)
747 __kfree_skb(opt_skb);
748 kfree_skb(skb);
749 return 0;
752 static int dccp_v6_rcv(struct sk_buff *skb)
754 const struct dccp_hdr *dh;
755 struct sock *sk;
756 int min_cov;
758 /* Step 1: Check header basics */
760 if (dccp_invalid_packet(skb))
761 goto discard_it;
763 /* Step 1: If header checksum is incorrect, drop packet and return. */
764 if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
765 &ipv6_hdr(skb)->daddr)) {
766 DCCP_WARN("dropped packet with invalid checksum\n");
767 goto discard_it;
770 dh = dccp_hdr(skb);
772 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh);
773 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
775 if (dccp_packet_without_ack(skb))
776 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
777 else
778 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
780 /* Step 2:
781 * Look up flow ID in table and get corresponding socket */
782 sk = __inet6_lookup_skb(&dccp_hashinfo, skb,
783 dh->dccph_sport, dh->dccph_dport);
785 * Step 2:
786 * If no socket ...
788 if (sk == NULL) {
789 dccp_pr_debug("failed to look up flow ID in table and "
790 "get corresponding socket\n");
791 goto no_dccp_socket;
795 * Step 2:
796 * ... or S.state == TIMEWAIT,
797 * Generate Reset(No Connection) unless P.type == Reset
798 * Drop packet and return
800 if (sk->sk_state == DCCP_TIME_WAIT) {
801 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
802 inet_twsk_put(inet_twsk(sk));
803 goto no_dccp_socket;
807 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
808 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
809 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
811 min_cov = dccp_sk(sk)->dccps_pcrlen;
812 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
813 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
814 dh->dccph_cscov, min_cov);
815 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
816 goto discard_and_relse;
819 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
820 goto discard_and_relse;
822 return sk_receive_skb(sk, skb, 1) ? -1 : 0;
824 no_dccp_socket:
825 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
826 goto discard_it;
828 * Step 2:
829 * If no socket ...
830 * Generate Reset(No Connection) unless P.type == Reset
831 * Drop packet and return
833 if (dh->dccph_type != DCCP_PKT_RESET) {
834 DCCP_SKB_CB(skb)->dccpd_reset_code =
835 DCCP_RESET_CODE_NO_CONNECTION;
836 dccp_v6_ctl_send_reset(sk, skb);
839 discard_it:
840 kfree_skb(skb);
841 return 0;
843 discard_and_relse:
844 sock_put(sk);
845 goto discard_it;
848 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
849 int addr_len)
851 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
852 struct inet_connection_sock *icsk = inet_csk(sk);
853 struct inet_sock *inet = inet_sk(sk);
854 struct ipv6_pinfo *np = inet6_sk(sk);
855 struct dccp_sock *dp = dccp_sk(sk);
856 struct in6_addr *saddr = NULL, *final_p, final;
857 struct flowi6 fl6;
858 struct dst_entry *dst;
859 int addr_type;
860 int err;
862 dp->dccps_role = DCCP_ROLE_CLIENT;
864 if (addr_len < SIN6_LEN_RFC2133)
865 return -EINVAL;
867 if (usin->sin6_family != AF_INET6)
868 return -EAFNOSUPPORT;
870 memset(&fl6, 0, sizeof(fl6));
872 if (np->sndflow) {
873 fl6.flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
874 IP6_ECN_flow_init(fl6.flowlabel);
875 if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) {
876 struct ip6_flowlabel *flowlabel;
877 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
878 if (flowlabel == NULL)
879 return -EINVAL;
880 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
881 fl6_sock_release(flowlabel);
885 * connect() to INADDR_ANY means loopback (BSD'ism).
887 if (ipv6_addr_any(&usin->sin6_addr))
888 usin->sin6_addr.s6_addr[15] = 1;
890 addr_type = ipv6_addr_type(&usin->sin6_addr);
892 if (addr_type & IPV6_ADDR_MULTICAST)
893 return -ENETUNREACH;
895 if (addr_type & IPV6_ADDR_LINKLOCAL) {
896 if (addr_len >= sizeof(struct sockaddr_in6) &&
897 usin->sin6_scope_id) {
898 /* If interface is set while binding, indices
899 * must coincide.
901 if (sk->sk_bound_dev_if &&
902 sk->sk_bound_dev_if != usin->sin6_scope_id)
903 return -EINVAL;
905 sk->sk_bound_dev_if = usin->sin6_scope_id;
908 /* Connect to link-local address requires an interface */
909 if (!sk->sk_bound_dev_if)
910 return -EINVAL;
913 ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
914 np->flow_label = fl6.flowlabel;
917 * DCCP over IPv4
919 if (addr_type == IPV6_ADDR_MAPPED) {
920 u32 exthdrlen = icsk->icsk_ext_hdr_len;
921 struct sockaddr_in sin;
923 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
925 if (__ipv6_only_sock(sk))
926 return -ENETUNREACH;
928 sin.sin_family = AF_INET;
929 sin.sin_port = usin->sin6_port;
930 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
932 icsk->icsk_af_ops = &dccp_ipv6_mapped;
933 sk->sk_backlog_rcv = dccp_v4_do_rcv;
935 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
936 if (err) {
937 icsk->icsk_ext_hdr_len = exthdrlen;
938 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
939 sk->sk_backlog_rcv = dccp_v6_do_rcv;
940 goto failure;
942 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
943 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, &np->rcv_saddr);
945 return err;
948 if (!ipv6_addr_any(&np->rcv_saddr))
949 saddr = &np->rcv_saddr;
951 fl6.flowi6_proto = IPPROTO_DCCP;
952 ipv6_addr_copy(&fl6.daddr, &np->daddr);
953 ipv6_addr_copy(&fl6.saddr, saddr ? saddr : &np->saddr);
954 fl6.flowi6_oif = sk->sk_bound_dev_if;
955 fl6.fl6_dport = usin->sin6_port;
956 fl6.fl6_sport = inet->inet_sport;
957 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
959 final_p = fl6_update_dst(&fl6, np->opt, &final);
961 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true);
962 if (IS_ERR(dst)) {
963 err = PTR_ERR(dst);
964 goto failure;
967 if (saddr == NULL) {
968 saddr = &fl6.saddr;
969 ipv6_addr_copy(&np->rcv_saddr, saddr);
972 /* set the source address */
973 ipv6_addr_copy(&np->saddr, saddr);
974 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
976 __ip6_dst_store(sk, dst, NULL, NULL);
978 icsk->icsk_ext_hdr_len = 0;
979 if (np->opt != NULL)
980 icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
981 np->opt->opt_nflen);
983 inet->inet_dport = usin->sin6_port;
985 dccp_set_state(sk, DCCP_REQUESTING);
986 err = inet6_hash_connect(&dccp_death_row, sk);
987 if (err)
988 goto late_failure;
990 dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
991 np->daddr.s6_addr32,
992 inet->inet_sport,
993 inet->inet_dport);
994 err = dccp_connect(sk);
995 if (err)
996 goto late_failure;
998 return 0;
1000 late_failure:
1001 dccp_set_state(sk, DCCP_CLOSED);
1002 __sk_dst_reset(sk);
1003 failure:
1004 inet->inet_dport = 0;
1005 sk->sk_route_caps = 0;
1006 return err;
1009 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
1010 .queue_xmit = inet6_csk_xmit,
1011 .send_check = dccp_v6_send_check,
1012 .rebuild_header = inet6_sk_rebuild_header,
1013 .conn_request = dccp_v6_conn_request,
1014 .syn_recv_sock = dccp_v6_request_recv_sock,
1015 .net_header_len = sizeof(struct ipv6hdr),
1016 .setsockopt = ipv6_setsockopt,
1017 .getsockopt = ipv6_getsockopt,
1018 .addr2sockaddr = inet6_csk_addr2sockaddr,
1019 .sockaddr_len = sizeof(struct sockaddr_in6),
1020 .bind_conflict = inet6_csk_bind_conflict,
1021 #ifdef CONFIG_COMPAT
1022 .compat_setsockopt = compat_ipv6_setsockopt,
1023 .compat_getsockopt = compat_ipv6_getsockopt,
1024 #endif
1028 * DCCP over IPv4 via INET6 API
1030 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
1031 .queue_xmit = ip_queue_xmit,
1032 .send_check = dccp_v4_send_check,
1033 .rebuild_header = inet_sk_rebuild_header,
1034 .conn_request = dccp_v6_conn_request,
1035 .syn_recv_sock = dccp_v6_request_recv_sock,
1036 .net_header_len = sizeof(struct iphdr),
1037 .setsockopt = ipv6_setsockopt,
1038 .getsockopt = ipv6_getsockopt,
1039 .addr2sockaddr = inet6_csk_addr2sockaddr,
1040 .sockaddr_len = sizeof(struct sockaddr_in6),
1041 #ifdef CONFIG_COMPAT
1042 .compat_setsockopt = compat_ipv6_setsockopt,
1043 .compat_getsockopt = compat_ipv6_getsockopt,
1044 #endif
1047 /* NOTE: A lot of things set to zero explicitly by call to
1048 * sk_alloc() so need not be done here.
1050 static int dccp_v6_init_sock(struct sock *sk)
1052 static __u8 dccp_v6_ctl_sock_initialized;
1053 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1055 if (err == 0) {
1056 if (unlikely(!dccp_v6_ctl_sock_initialized))
1057 dccp_v6_ctl_sock_initialized = 1;
1058 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1061 return err;
1064 static void dccp_v6_destroy_sock(struct sock *sk)
1066 dccp_destroy_sock(sk);
1067 inet6_destroy_sock(sk);
1070 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1071 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
1074 static struct proto dccp_v6_prot = {
1075 .name = "DCCPv6",
1076 .owner = THIS_MODULE,
1077 .close = dccp_close,
1078 .connect = dccp_v6_connect,
1079 .disconnect = dccp_disconnect,
1080 .ioctl = dccp_ioctl,
1081 .init = dccp_v6_init_sock,
1082 .setsockopt = dccp_setsockopt,
1083 .getsockopt = dccp_getsockopt,
1084 .sendmsg = dccp_sendmsg,
1085 .recvmsg = dccp_recvmsg,
1086 .backlog_rcv = dccp_v6_do_rcv,
1087 .hash = dccp_v6_hash,
1088 .unhash = inet_unhash,
1089 .accept = inet_csk_accept,
1090 .get_port = inet_csk_get_port,
1091 .shutdown = dccp_shutdown,
1092 .destroy = dccp_v6_destroy_sock,
1093 .orphan_count = &dccp_orphan_count,
1094 .max_header = MAX_DCCP_HEADER,
1095 .obj_size = sizeof(struct dccp6_sock),
1096 .slab_flags = SLAB_DESTROY_BY_RCU,
1097 .rsk_prot = &dccp6_request_sock_ops,
1098 .twsk_prot = &dccp6_timewait_sock_ops,
1099 .h.hashinfo = &dccp_hashinfo,
1100 #ifdef CONFIG_COMPAT
1101 .compat_setsockopt = compat_dccp_setsockopt,
1102 .compat_getsockopt = compat_dccp_getsockopt,
1103 #endif
1106 static const struct inet6_protocol dccp_v6_protocol = {
1107 .handler = dccp_v6_rcv,
1108 .err_handler = dccp_v6_err,
1109 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1112 static const struct proto_ops inet6_dccp_ops = {
1113 .family = PF_INET6,
1114 .owner = THIS_MODULE,
1115 .release = inet6_release,
1116 .bind = inet6_bind,
1117 .connect = inet_stream_connect,
1118 .socketpair = sock_no_socketpair,
1119 .accept = inet_accept,
1120 .getname = inet6_getname,
1121 .poll = dccp_poll,
1122 .ioctl = inet6_ioctl,
1123 .listen = inet_dccp_listen,
1124 .shutdown = inet_shutdown,
1125 .setsockopt = sock_common_setsockopt,
1126 .getsockopt = sock_common_getsockopt,
1127 .sendmsg = inet_sendmsg,
1128 .recvmsg = sock_common_recvmsg,
1129 .mmap = sock_no_mmap,
1130 .sendpage = sock_no_sendpage,
1131 #ifdef CONFIG_COMPAT
1132 .compat_setsockopt = compat_sock_common_setsockopt,
1133 .compat_getsockopt = compat_sock_common_getsockopt,
1134 #endif
1137 static struct inet_protosw dccp_v6_protosw = {
1138 .type = SOCK_DCCP,
1139 .protocol = IPPROTO_DCCP,
1140 .prot = &dccp_v6_prot,
1141 .ops = &inet6_dccp_ops,
1142 .flags = INET_PROTOSW_ICSK,
1145 static int __net_init dccp_v6_init_net(struct net *net)
1147 if (dccp_hashinfo.bhash == NULL)
1148 return -ESOCKTNOSUPPORT;
1150 return inet_ctl_sock_create(&net->dccp.v6_ctl_sk, PF_INET6,
1151 SOCK_DCCP, IPPROTO_DCCP, net);
1154 static void __net_exit dccp_v6_exit_net(struct net *net)
1156 inet_ctl_sock_destroy(net->dccp.v6_ctl_sk);
1159 static struct pernet_operations dccp_v6_ops = {
1160 .init = dccp_v6_init_net,
1161 .exit = dccp_v6_exit_net,
1164 static int __init dccp_v6_init(void)
1166 int err = proto_register(&dccp_v6_prot, 1);
1168 if (err != 0)
1169 goto out;
1171 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1172 if (err != 0)
1173 goto out_unregister_proto;
1175 inet6_register_protosw(&dccp_v6_protosw);
1177 err = register_pernet_subsys(&dccp_v6_ops);
1178 if (err != 0)
1179 goto out_destroy_ctl_sock;
1180 out:
1181 return err;
1183 out_destroy_ctl_sock:
1184 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1185 inet6_unregister_protosw(&dccp_v6_protosw);
1186 out_unregister_proto:
1187 proto_unregister(&dccp_v6_prot);
1188 goto out;
1191 static void __exit dccp_v6_exit(void)
1193 unregister_pernet_subsys(&dccp_v6_ops);
1194 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1195 inet6_unregister_protosw(&dccp_v6_protosw);
1196 proto_unregister(&dccp_v6_prot);
1199 module_init(dccp_v6_init);
1200 module_exit(dccp_v6_exit);
1203 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1204 * values directly, Also cover the case where the protocol is not specified,
1205 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1207 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6);
1208 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6);
1209 MODULE_LICENSE("GPL");
1210 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1211 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");