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>
28 #include <net/protocol.h>
29 #include <net/transp_v6.h>
30 #include <net/ip6_checksum.h>
32 #include <net/secure_seq.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
) {
51 __inet6_hash(sk
, NULL
);
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
);
88 struct ipv6_pinfo
*np
;
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
),
101 sk
= inet6_lookup(net
, &dccp_hashinfo
,
102 &hdr
->daddr
, dh
->dccph_dport
,
103 &hdr
->saddr
, dh
->dccph_sport
, inet6_iif(skb
));
106 ICMP6_INC_STATS_BH(net
, __in6_dev_get(skb
->dev
),
111 if (sk
->sk_state
== DCCP_TIME_WAIT
) {
112 inet_twsk_put(inet_twsk(sk
));
117 if (sock_owned_by_user(sk
))
118 NET_INC_STATS_BH(net
, LINUX_MIB_LOCKDROPPEDICMPS
);
120 if (sk
->sk_state
== DCCP_CLOSED
)
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
);
133 if (type
== ICMPV6_PKT_TOOBIG
) {
134 struct dst_entry
*dst
= NULL
;
136 if (sock_owned_by_user(sk
))
138 if ((1 << sk
->sk_state
) & (DCCPF_LISTEN
| DCCPF_CLOSED
))
141 /* icmp should have updated the destination cache entry */
142 dst
= __sk_dst_check(sk
, np
->dst_cookie
);
144 struct inet_sock
*inet
= inet_sk(sk
);
147 /* BUGGG_FUTURE: Again, it is not clear how
148 to handle rthdr case. Ignore this complexity
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);
162 sk
->sk_err_soft
= -PTR_ERR(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 */
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
;
181 if (sock_owned_by_user(sk
))
184 req
= inet6_csk_search_req(sk
, &prev
, dh
->dccph_dport
,
185 &hdr
->daddr
, &hdr
->saddr
,
191 * ICMPs are not backlogged, hence we cannot get an established
194 WARN_ON(req
->sk
!= NULL
);
196 if (seq
!= dccp_rsk(req
)->dreq_iss
) {
197 NET_INC_STATS_BH(net
, LINUX_MIB_OUTOFWINDOWICMPS
);
201 inet_csk_reqsk_queue_drop(sk
, req
, prev
);
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
);
211 * Wake people up to see the error
212 * (see connect in sock.c)
214 sk
->sk_error_report(sk
);
217 sk
->sk_err_soft
= err
;
221 if (!sock_owned_by_user(sk
) && np
->recverr
) {
223 sk
->sk_error_report(sk
);
225 sk
->sk_err_soft
= err
;
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
);
239 struct ipv6_txoptions
*opt
= NULL
;
240 struct in6_addr
*final_p
, final
;
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
);
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
));
257 final_p
= fl6_update_dst(&fl6
, opt
, &final
);
259 dst
= ip6_dst_lookup_flow(sk
, &fl6
, final_p
, false);
266 skb
= dccp_make_response(sk
, dst
, req
);
268 struct dccp_hdr
*dh
= dccp_hdr(skb
);
270 dh
->dccph_checksum
= dccp_v6_csum_finish(skb
,
273 ipv6_addr_copy(&fl6
.daddr
, &ireq6
->rmt_addr
);
274 err
= ip6_xmit(sk
, skb
, &fl6
, opt
);
275 err
= net_xmit_eval(err
);
279 if (opt
!= NULL
&& opt
!= np
->opt
)
280 sock_kfree_s(sk
, opt
, opt
->tot_len
);
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
;
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
)
304 if (!ipv6_unicast_destination(rxskb
))
307 skb
= dccp_ctl_make_reset(ctl_sk
, rxskb
);
311 rxip6h
= ipv6_hdr(rxskb
);
312 dccp_hdr(skb
)->dccph_checksum
= dccp_v6_csum_finish(skb
, &rxip6h
->saddr
,
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);
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
);
338 static struct request_sock_ops dccp6_request_sock_ops
= {
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
);
352 struct request_sock
**prev
;
353 /* Find possible connection requests. */
354 struct request_sock
*req
= inet6_csk_search_req(sk
, &prev
,
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
),
367 if (nsk
->sk_state
!= DCCP_TIME_WAIT
) {
371 inet_twsk_put(inet_twsk(nsk
));
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
;
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
))
404 if (sk_acceptq_is_full(sk
) && inet_csk_reqsk_queue_young(sk
) > 1)
407 req
= inet6_reqsk_alloc(&dccp6_request_sock_ops
);
411 if (dccp_reqsk_init(req
, dccp_sk(sk
), skb
))
414 dreq
= dccp_rsk(req
);
415 if (dccp_parse_options(sk
, dreq
, skb
))
418 if (security_inet_conn_request(sk
, skb
, req
))
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
))
453 inet6_csk_reqsk_queue_hash_add(sk
, req
, DCCP_TIMEOUT_INIT
);
459 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS
);
463 static struct sock
*dccp_v6_request_recv_sock(struct sock
*sk
,
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
;
473 struct ipv6_txoptions
*opt
;
475 if (skb
->protocol
== htons(ETH_P_IP
)) {
479 newsk
= dccp_v4_request_recv_sock(sk
, skb
, req
, dst
);
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
;
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.
513 dccp_sync_mss(newsk
, inet_csk(newsk
)->icsk_pmtu_cookie
);
520 if (sk_acceptq_is_full(sk
))
524 struct in6_addr
*final_p
, final
;
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);
542 newsk
= dccp_create_openreq_child(sk
, req
, skb
);
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
|
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
;
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
);
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.
596 newnp
->opt
= ipv6_dup_options(newsk
, 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) {
615 __inet6_hash(newsk
, NULL
);
620 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_LISTENOVERFLOWS
);
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
);
630 /* The socket must have it's spinlock held when we get
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
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
))
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.
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
))
686 /* XXX This is where we would goto ipv6_pktoptions. */
687 __kfree_skb(opt_skb
);
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
701 * (* Generate a new socket and switch to that socket *)
702 * Set S := new socket for this port pair
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 *)
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
);
722 * Queue it on the new socket if the new socket is active,
723 * otherwise we just shortcircuit this and continue with
727 if (dccp_child_process(sk
, nsk
, skb
))
730 __kfree_skb(opt_skb
);
735 if (dccp_rcv_state_process(sk
, skb
, dccp_hdr(skb
), skb
->len
))
738 /* XXX This is where we would goto ipv6_pktoptions. */
739 __kfree_skb(opt_skb
);
744 dccp_v6_ctl_send_reset(sk
, skb
);
747 __kfree_skb(opt_skb
);
752 static int dccp_v6_rcv(struct sk_buff
*skb
)
754 const struct dccp_hdr
*dh
;
758 /* Step 1: Check header basics */
760 if (dccp_invalid_packet(skb
))
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");
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
;
778 DCCP_SKB_CB(skb
)->dccpd_ack_seq
= dccp_hdr_ack_seq(skb
);
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
);
789 dccp_pr_debug("failed to look up flow ID in table and "
790 "get corresponding socket\n");
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
));
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;
825 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
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
);
848 static int dccp_v6_connect(struct sock
*sk
, struct sockaddr
*uaddr
,
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
;
858 struct dst_entry
*dst
;
862 dp
->dccps_role
= DCCP_ROLE_CLIENT
;
864 if (addr_len
< SIN6_LEN_RFC2133
)
867 if (usin
->sin6_family
!= AF_INET6
)
868 return -EAFNOSUPPORT
;
870 memset(&fl6
, 0, sizeof(fl6
));
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
)
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
)
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
901 if (sk
->sk_bound_dev_if
&&
902 sk
->sk_bound_dev_if
!= usin
->sin6_scope_id
)
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
)
913 ipv6_addr_copy(&np
->daddr
, &usin
->sin6_addr
);
914 np
->flow_label
= fl6
.flowlabel
;
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
))
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
));
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
;
942 ipv6_addr_set_v4mapped(inet
->inet_saddr
, &np
->saddr
);
943 ipv6_addr_set_v4mapped(inet
->inet_rcv_saddr
, &np
->rcv_saddr
);
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);
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;
980 icsk
->icsk_ext_hdr_len
= (np
->opt
->opt_flen
+
983 inet
->inet_dport
= usin
->sin6_port
;
985 dccp_set_state(sk
, DCCP_REQUESTING
);
986 err
= inet6_hash_connect(&dccp_death_row
, sk
);
990 dp
->dccps_iss
= secure_dccpv6_sequence_number(np
->saddr
.s6_addr32
,
994 err
= dccp_connect(sk
);
1001 dccp_set_state(sk
, DCCP_CLOSED
);
1004 inet
->inet_dport
= 0;
1005 sk
->sk_route_caps
= 0;
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
,
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
,
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
);
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
;
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
= {
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
,
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
= {
1114 .owner
= THIS_MODULE
,
1115 .release
= inet6_release
,
1117 .connect
= inet_stream_connect
,
1118 .socketpair
= sock_no_socketpair
,
1119 .accept
= inet_accept
,
1120 .getname
= inet6_getname
,
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
,
1137 static struct inet_protosw dccp_v6_protosw
= {
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);
1171 err
= inet6_add_protocol(&dccp_v6_protocol
, IPPROTO_DCCP
);
1173 goto out_unregister_proto
;
1175 inet6_register_protosw(&dccp_v6_protosw
);
1177 err
= register_pernet_subsys(&dccp_v6_ops
);
1179 goto out_destroy_ctl_sock
;
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
);
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");