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/xfrm.h>
19 #include <net/addrconf.h>
20 #include <net/inet_common.h>
21 #include <net/inet_hashtables.h>
22 #include <net/inet_sock.h>
23 #include <net/inet6_connection_sock.h>
24 #include <net/inet6_hashtables.h>
25 #include <net/ip6_route.h>
27 #include <net/protocol.h>
28 #include <net/transp_v6.h>
29 #include <net/ip6_checksum.h>
36 /* The per-net dccp.v6_ctl_sk is used for sending RSTs and ACKs */
38 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped
;
39 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops
;
41 static void dccp_v6_hash(struct sock
*sk
)
43 if (sk
->sk_state
!= DCCP_CLOSED
) {
44 if (inet_csk(sk
)->icsk_af_ops
== &dccp_ipv6_mapped
) {
49 __inet6_hash(sk
, NULL
);
54 /* add pseudo-header to DCCP checksum stored in skb->csum */
55 static inline __sum16
dccp_v6_csum_finish(struct sk_buff
*skb
,
56 struct in6_addr
*saddr
,
57 struct in6_addr
*daddr
)
59 return csum_ipv6_magic(saddr
, daddr
, skb
->len
, IPPROTO_DCCP
, skb
->csum
);
62 static inline void dccp_v6_send_check(struct sock
*sk
, int unused_value
,
65 struct ipv6_pinfo
*np
= inet6_sk(sk
);
66 struct dccp_hdr
*dh
= dccp_hdr(skb
);
68 dccp_csum_outgoing(skb
);
69 dh
->dccph_checksum
= dccp_v6_csum_finish(skb
, &np
->saddr
, &np
->daddr
);
72 static inline __u32
secure_dccpv6_sequence_number(__be32
*saddr
, __be32
*daddr
,
73 __be16 sport
, __be16 dport
)
75 return secure_tcpv6_sequence_number(saddr
, daddr
, sport
, dport
);
78 static inline __u32
dccp_v6_init_sequence(struct sk_buff
*skb
)
80 return secure_dccpv6_sequence_number(ipv6_hdr(skb
)->daddr
.s6_addr32
,
81 ipv6_hdr(skb
)->saddr
.s6_addr32
,
82 dccp_hdr(skb
)->dccph_dport
,
83 dccp_hdr(skb
)->dccph_sport
);
87 static void dccp_v6_err(struct sk_buff
*skb
, struct inet6_skb_parm
*opt
,
88 u8 type
, u8 code
, int offset
, __be32 info
)
90 struct ipv6hdr
*hdr
= (struct ipv6hdr
*)skb
->data
;
91 const struct dccp_hdr
*dh
= (struct dccp_hdr
*)(skb
->data
+ offset
);
93 struct ipv6_pinfo
*np
;
97 struct net
*net
= dev_net(skb
->dev
);
99 if (skb
->len
< offset
+ sizeof(*dh
) ||
100 skb
->len
< offset
+ __dccp_basic_hdr_len(dh
)) {
101 ICMP6_INC_STATS_BH(net
, __in6_dev_get(skb
->dev
),
106 sk
= inet6_lookup(net
, &dccp_hashinfo
,
107 &hdr
->daddr
, dh
->dccph_dport
,
108 &hdr
->saddr
, dh
->dccph_sport
, inet6_iif(skb
));
111 ICMP6_INC_STATS_BH(net
, __in6_dev_get(skb
->dev
),
116 if (sk
->sk_state
== DCCP_TIME_WAIT
) {
117 inet_twsk_put(inet_twsk(sk
));
122 if (sock_owned_by_user(sk
))
123 NET_INC_STATS_BH(net
, LINUX_MIB_LOCKDROPPEDICMPS
);
125 if (sk
->sk_state
== DCCP_CLOSED
)
129 seq
= dccp_hdr_seq(dh
);
130 if ((1 << sk
->sk_state
) & ~(DCCPF_REQUESTING
| DCCPF_LISTEN
) &&
131 !between48(seq
, dp
->dccps_awl
, dp
->dccps_awh
)) {
132 NET_INC_STATS_BH(net
, LINUX_MIB_OUTOFWINDOWICMPS
);
138 if (type
== ICMPV6_PKT_TOOBIG
) {
139 struct dst_entry
*dst
= NULL
;
141 if (sock_owned_by_user(sk
))
143 if ((1 << sk
->sk_state
) & (DCCPF_LISTEN
| DCCPF_CLOSED
))
146 /* icmp should have updated the destination cache entry */
147 dst
= __sk_dst_check(sk
, np
->dst_cookie
);
149 struct inet_sock
*inet
= inet_sk(sk
);
152 /* BUGGG_FUTURE: Again, it is not clear how
153 to handle rthdr case. Ignore this complexity
156 memset(&fl
, 0, sizeof(fl
));
157 fl
.proto
= IPPROTO_DCCP
;
158 ipv6_addr_copy(&fl
.fl6_dst
, &np
->daddr
);
159 ipv6_addr_copy(&fl
.fl6_src
, &np
->saddr
);
160 fl
.oif
= sk
->sk_bound_dev_if
;
161 fl
.fl_ip_dport
= inet
->inet_dport
;
162 fl
.fl_ip_sport
= inet
->inet_sport
;
163 security_sk_classify_flow(sk
, &fl
);
165 err
= ip6_dst_lookup(sk
, &dst
, &fl
);
167 sk
->sk_err_soft
= -err
;
171 err
= xfrm_lookup(net
, &dst
, &fl
, sk
, 0);
173 sk
->sk_err_soft
= -err
;
179 if (inet_csk(sk
)->icsk_pmtu_cookie
> dst_mtu(dst
)) {
180 dccp_sync_mss(sk
, dst_mtu(dst
));
181 } /* else let the usual retransmit timer handle it */
186 icmpv6_err_convert(type
, code
, &err
);
188 /* Might be for an request_sock */
189 switch (sk
->sk_state
) {
190 struct request_sock
*req
, **prev
;
192 if (sock_owned_by_user(sk
))
195 req
= inet6_csk_search_req(sk
, &prev
, dh
->dccph_dport
,
196 &hdr
->daddr
, &hdr
->saddr
,
202 * ICMPs are not backlogged, hence we cannot get an established
205 WARN_ON(req
->sk
!= NULL
);
207 if (seq
!= dccp_rsk(req
)->dreq_iss
) {
208 NET_INC_STATS_BH(net
, LINUX_MIB_OUTOFWINDOWICMPS
);
212 inet_csk_reqsk_queue_drop(sk
, req
, prev
);
215 case DCCP_REQUESTING
:
216 case DCCP_RESPOND
: /* Cannot happen.
217 It can, it SYNs are crossed. --ANK */
218 if (!sock_owned_by_user(sk
)) {
219 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS
);
222 * Wake people up to see the error
223 * (see connect in sock.c)
225 sk
->sk_error_report(sk
);
228 sk
->sk_err_soft
= err
;
232 if (!sock_owned_by_user(sk
) && np
->recverr
) {
234 sk
->sk_error_report(sk
);
236 sk
->sk_err_soft
= err
;
244 static int dccp_v6_send_response(struct sock
*sk
, struct request_sock
*req
,
245 struct request_values
*rv_unused
)
247 struct inet6_request_sock
*ireq6
= inet6_rsk(req
);
248 struct ipv6_pinfo
*np
= inet6_sk(sk
);
250 struct ipv6_txoptions
*opt
= NULL
;
251 struct in6_addr
*final_p
= NULL
, final
;
254 struct dst_entry
*dst
;
256 memset(&fl
, 0, sizeof(fl
));
257 fl
.proto
= IPPROTO_DCCP
;
258 ipv6_addr_copy(&fl
.fl6_dst
, &ireq6
->rmt_addr
);
259 ipv6_addr_copy(&fl
.fl6_src
, &ireq6
->loc_addr
);
260 fl
.fl6_flowlabel
= 0;
262 fl
.fl_ip_dport
= inet_rsk(req
)->rmt_port
;
263 fl
.fl_ip_sport
= inet_rsk(req
)->loc_port
;
264 security_req_classify_flow(req
, &fl
);
268 if (opt
!= NULL
&& opt
->srcrt
!= NULL
) {
269 const struct rt0_hdr
*rt0
= (struct rt0_hdr
*)opt
->srcrt
;
271 ipv6_addr_copy(&final
, &fl
.fl6_dst
);
272 ipv6_addr_copy(&fl
.fl6_dst
, rt0
->addr
);
276 err
= ip6_dst_lookup(sk
, &dst
, &fl
);
281 ipv6_addr_copy(&fl
.fl6_dst
, final_p
);
283 err
= xfrm_lookup(sock_net(sk
), &dst
, &fl
, sk
, 0);
287 skb
= dccp_make_response(sk
, dst
, req
);
289 struct dccp_hdr
*dh
= dccp_hdr(skb
);
291 dh
->dccph_checksum
= dccp_v6_csum_finish(skb
,
294 ipv6_addr_copy(&fl
.fl6_dst
, &ireq6
->rmt_addr
);
295 err
= ip6_xmit(sk
, skb
, &fl
, opt
, 0);
296 err
= net_xmit_eval(err
);
300 if (opt
!= NULL
&& opt
!= np
->opt
)
301 sock_kfree_s(sk
, opt
, opt
->tot_len
);
306 static void dccp_v6_reqsk_destructor(struct request_sock
*req
)
308 dccp_feat_list_purge(&dccp_rsk(req
)->dreq_featneg
);
309 if (inet6_rsk(req
)->pktopts
!= NULL
)
310 kfree_skb(inet6_rsk(req
)->pktopts
);
313 static void dccp_v6_ctl_send_reset(struct sock
*sk
, struct sk_buff
*rxskb
)
315 struct ipv6hdr
*rxip6h
;
318 struct net
*net
= dev_net(skb_dst(rxskb
)->dev
);
319 struct sock
*ctl_sk
= net
->dccp
.v6_ctl_sk
;
320 struct dst_entry
*dst
;
322 if (dccp_hdr(rxskb
)->dccph_type
== DCCP_PKT_RESET
)
325 if (!ipv6_unicast_destination(rxskb
))
328 skb
= dccp_ctl_make_reset(ctl_sk
, rxskb
);
332 rxip6h
= ipv6_hdr(rxskb
);
333 dccp_hdr(skb
)->dccph_checksum
= dccp_v6_csum_finish(skb
, &rxip6h
->saddr
,
336 memset(&fl
, 0, sizeof(fl
));
337 ipv6_addr_copy(&fl
.fl6_dst
, &rxip6h
->saddr
);
338 ipv6_addr_copy(&fl
.fl6_src
, &rxip6h
->daddr
);
340 fl
.proto
= IPPROTO_DCCP
;
341 fl
.oif
= inet6_iif(rxskb
);
342 fl
.fl_ip_dport
= dccp_hdr(skb
)->dccph_dport
;
343 fl
.fl_ip_sport
= dccp_hdr(skb
)->dccph_sport
;
344 security_skb_classify_flow(rxskb
, &fl
);
346 /* sk = NULL, but it is safe for now. RST socket required. */
347 if (!ip6_dst_lookup(ctl_sk
, &dst
, &fl
)) {
348 if (xfrm_lookup(net
, &dst
, &fl
, NULL
, 0) >= 0) {
349 skb_dst_set(skb
, dst
);
350 ip6_xmit(ctl_sk
, skb
, &fl
, NULL
, 0);
351 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS
);
352 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS
);
360 static struct request_sock_ops dccp6_request_sock_ops
= {
362 .obj_size
= sizeof(struct dccp6_request_sock
),
363 .rtx_syn_ack
= dccp_v6_send_response
,
364 .send_ack
= dccp_reqsk_send_ack
,
365 .destructor
= dccp_v6_reqsk_destructor
,
366 .send_reset
= dccp_v6_ctl_send_reset
,
369 static struct sock
*dccp_v6_hnd_req(struct sock
*sk
,struct sk_buff
*skb
)
371 const struct dccp_hdr
*dh
= dccp_hdr(skb
);
372 const struct ipv6hdr
*iph
= ipv6_hdr(skb
);
374 struct request_sock
**prev
;
375 /* Find possible connection requests. */
376 struct request_sock
*req
= inet6_csk_search_req(sk
, &prev
,
382 return dccp_check_req(sk
, skb
, req
, prev
);
384 nsk
= __inet6_lookup_established(sock_net(sk
), &dccp_hashinfo
,
385 &iph
->saddr
, dh
->dccph_sport
,
386 &iph
->daddr
, ntohs(dh
->dccph_dport
),
389 if (nsk
->sk_state
!= DCCP_TIME_WAIT
) {
393 inet_twsk_put(inet_twsk(nsk
));
400 static int dccp_v6_conn_request(struct sock
*sk
, struct sk_buff
*skb
)
402 struct request_sock
*req
;
403 struct dccp_request_sock
*dreq
;
404 struct inet6_request_sock
*ireq6
;
405 struct ipv6_pinfo
*np
= inet6_sk(sk
);
406 const __be32 service
= dccp_hdr_request(skb
)->dccph_req_service
;
407 struct dccp_skb_cb
*dcb
= DCCP_SKB_CB(skb
);
409 if (skb
->protocol
== htons(ETH_P_IP
))
410 return dccp_v4_conn_request(sk
, skb
);
412 if (!ipv6_unicast_destination(skb
))
413 return 0; /* discard, don't send a reset here */
415 if (dccp_bad_service_code(sk
, service
)) {
416 dcb
->dccpd_reset_code
= DCCP_RESET_CODE_BAD_SERVICE_CODE
;
420 * There are no SYN attacks on IPv6, yet...
422 dcb
->dccpd_reset_code
= DCCP_RESET_CODE_TOO_BUSY
;
423 if (inet_csk_reqsk_queue_is_full(sk
))
426 if (sk_acceptq_is_full(sk
) && inet_csk_reqsk_queue_young(sk
) > 1)
429 req
= inet6_reqsk_alloc(&dccp6_request_sock_ops
);
433 if (dccp_reqsk_init(req
, dccp_sk(sk
), skb
))
436 dreq
= dccp_rsk(req
);
437 if (dccp_parse_options(sk
, dreq
, skb
))
440 if (security_inet_conn_request(sk
, skb
, req
))
443 ireq6
= inet6_rsk(req
);
444 ipv6_addr_copy(&ireq6
->rmt_addr
, &ipv6_hdr(skb
)->saddr
);
445 ipv6_addr_copy(&ireq6
->loc_addr
, &ipv6_hdr(skb
)->daddr
);
447 if (ipv6_opt_accepted(sk
, skb
) ||
448 np
->rxopt
.bits
.rxinfo
|| np
->rxopt
.bits
.rxoinfo
||
449 np
->rxopt
.bits
.rxhlim
|| np
->rxopt
.bits
.rxohlim
) {
450 atomic_inc(&skb
->users
);
451 ireq6
->pktopts
= skb
;
453 ireq6
->iif
= sk
->sk_bound_dev_if
;
455 /* So that link locals have meaning */
456 if (!sk
->sk_bound_dev_if
&&
457 ipv6_addr_type(&ireq6
->rmt_addr
) & IPV6_ADDR_LINKLOCAL
)
458 ireq6
->iif
= inet6_iif(skb
);
461 * Step 3: Process LISTEN state
463 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
465 * In fact we defer setting S.GSR, S.SWL, S.SWH to
466 * dccp_create_openreq_child.
468 dreq
->dreq_isr
= dcb
->dccpd_seq
;
469 dreq
->dreq_iss
= dccp_v6_init_sequence(skb
);
470 dreq
->dreq_service
= service
;
472 if (dccp_v6_send_response(sk
, req
, NULL
))
475 inet6_csk_reqsk_queue_hash_add(sk
, req
, DCCP_TIMEOUT_INIT
);
481 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS
);
485 static struct sock
*dccp_v6_request_recv_sock(struct sock
*sk
,
487 struct request_sock
*req
,
488 struct dst_entry
*dst
)
490 struct inet6_request_sock
*ireq6
= inet6_rsk(req
);
491 struct ipv6_pinfo
*newnp
, *np
= inet6_sk(sk
);
492 struct inet_sock
*newinet
;
493 struct dccp_sock
*newdp
;
494 struct dccp6_sock
*newdp6
;
496 struct ipv6_txoptions
*opt
;
498 if (skb
->protocol
== htons(ETH_P_IP
)) {
502 newsk
= dccp_v4_request_recv_sock(sk
, skb
, req
, dst
);
506 newdp6
= (struct dccp6_sock
*)newsk
;
507 newdp
= dccp_sk(newsk
);
508 newinet
= inet_sk(newsk
);
509 newinet
->pinet6
= &newdp6
->inet6
;
510 newnp
= inet6_sk(newsk
);
512 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
514 ipv6_addr_set_v4mapped(newinet
->inet_daddr
, &newnp
->daddr
);
516 ipv6_addr_set_v4mapped(newinet
->inet_saddr
, &newnp
->saddr
);
518 ipv6_addr_copy(&newnp
->rcv_saddr
, &newnp
->saddr
);
520 inet_csk(newsk
)->icsk_af_ops
= &dccp_ipv6_mapped
;
521 newsk
->sk_backlog_rcv
= dccp_v4_do_rcv
;
522 newnp
->pktoptions
= NULL
;
524 newnp
->mcast_oif
= inet6_iif(skb
);
525 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
528 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
529 * here, dccp_create_openreq_child now does this for us, see the comment in
530 * that function for the gory details. -acme
533 /* It is tricky place. Until this moment IPv4 tcp
534 worked with IPv6 icsk.icsk_af_ops.
537 dccp_sync_mss(newsk
, inet_csk(newsk
)->icsk_pmtu_cookie
);
544 if (sk_acceptq_is_full(sk
))
548 struct in6_addr
*final_p
= NULL
, final
;
551 memset(&fl
, 0, sizeof(fl
));
552 fl
.proto
= IPPROTO_DCCP
;
553 ipv6_addr_copy(&fl
.fl6_dst
, &ireq6
->rmt_addr
);
554 if (opt
!= NULL
&& opt
->srcrt
!= NULL
) {
555 const struct rt0_hdr
*rt0
= (struct rt0_hdr
*)opt
->srcrt
;
557 ipv6_addr_copy(&final
, &fl
.fl6_dst
);
558 ipv6_addr_copy(&fl
.fl6_dst
, rt0
->addr
);
561 ipv6_addr_copy(&fl
.fl6_src
, &ireq6
->loc_addr
);
562 fl
.oif
= sk
->sk_bound_dev_if
;
563 fl
.fl_ip_dport
= inet_rsk(req
)->rmt_port
;
564 fl
.fl_ip_sport
= inet_rsk(req
)->loc_port
;
565 security_sk_classify_flow(sk
, &fl
);
567 if (ip6_dst_lookup(sk
, &dst
, &fl
))
571 ipv6_addr_copy(&fl
.fl6_dst
, final_p
);
573 if ((xfrm_lookup(sock_net(sk
), &dst
, &fl
, sk
, 0)) < 0)
577 newsk
= dccp_create_openreq_child(sk
, req
, skb
);
582 * No need to charge this sock to the relevant IPv6 refcnt debug socks
583 * count here, dccp_create_openreq_child now does this for us, see the
584 * comment in that function for the gory details. -acme
587 __ip6_dst_store(newsk
, dst
, NULL
, NULL
);
588 newsk
->sk_route_caps
= dst
->dev
->features
& ~(NETIF_F_IP_CSUM
|
590 newdp6
= (struct dccp6_sock
*)newsk
;
591 newinet
= inet_sk(newsk
);
592 newinet
->pinet6
= &newdp6
->inet6
;
593 newdp
= dccp_sk(newsk
);
594 newnp
= inet6_sk(newsk
);
596 memcpy(newnp
, np
, sizeof(struct ipv6_pinfo
));
598 ipv6_addr_copy(&newnp
->daddr
, &ireq6
->rmt_addr
);
599 ipv6_addr_copy(&newnp
->saddr
, &ireq6
->loc_addr
);
600 ipv6_addr_copy(&newnp
->rcv_saddr
, &ireq6
->loc_addr
);
601 newsk
->sk_bound_dev_if
= ireq6
->iif
;
603 /* Now IPv6 options...
605 First: no IPv4 options.
610 newnp
->rxopt
.all
= np
->rxopt
.all
;
612 /* Clone pktoptions received with SYN */
613 newnp
->pktoptions
= NULL
;
614 if (ireq6
->pktopts
!= NULL
) {
615 newnp
->pktoptions
= skb_clone(ireq6
->pktopts
, GFP_ATOMIC
);
616 kfree_skb(ireq6
->pktopts
);
617 ireq6
->pktopts
= NULL
;
618 if (newnp
->pktoptions
)
619 skb_set_owner_r(newnp
->pktoptions
, newsk
);
622 newnp
->mcast_oif
= inet6_iif(skb
);
623 newnp
->mcast_hops
= ipv6_hdr(skb
)->hop_limit
;
626 * Clone native IPv6 options from listening socket (if any)
628 * Yes, keeping reference count would be much more clever, but we make
629 * one more one thing there: reattach optmem to newsk.
632 newnp
->opt
= ipv6_dup_options(newsk
, opt
);
634 sock_kfree_s(sk
, opt
, opt
->tot_len
);
637 inet_csk(newsk
)->icsk_ext_hdr_len
= 0;
638 if (newnp
->opt
!= NULL
)
639 inet_csk(newsk
)->icsk_ext_hdr_len
= (newnp
->opt
->opt_nflen
+
640 newnp
->opt
->opt_flen
);
642 dccp_sync_mss(newsk
, dst_mtu(dst
));
644 newinet
->inet_daddr
= newinet
->inet_saddr
= LOOPBACK4_IPV6
;
645 newinet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
647 __inet6_hash(newsk
, NULL
);
648 __inet_inherit_port(sk
, newsk
);
653 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_LISTENOVERFLOWS
);
655 NET_INC_STATS_BH(sock_net(sk
), LINUX_MIB_LISTENDROPS
);
656 if (opt
!= NULL
&& opt
!= np
->opt
)
657 sock_kfree_s(sk
, opt
, opt
->tot_len
);
662 /* The socket must have it's spinlock held when we get
665 * We have a potential double-lock case here, so even when
666 * doing backlog processing we use the BH locking scheme.
667 * This is because we cannot sleep with the original spinlock
670 static int dccp_v6_do_rcv(struct sock
*sk
, struct sk_buff
*skb
)
672 struct ipv6_pinfo
*np
= inet6_sk(sk
);
673 struct sk_buff
*opt_skb
= NULL
;
675 /* Imagine: socket is IPv6. IPv4 packet arrives,
676 goes to IPv4 receive handler and backlogged.
677 From backlog it always goes here. Kerboom...
678 Fortunately, dccp_rcv_established and rcv_established
679 handle them correctly, but it is not case with
680 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
683 if (skb
->protocol
== htons(ETH_P_IP
))
684 return dccp_v4_do_rcv(sk
, skb
);
686 if (sk_filter(sk
, skb
))
690 * socket locking is here for SMP purposes as backlog rcv is currently
691 * called with bh processing disabled.
694 /* Do Stevens' IPV6_PKTOPTIONS.
696 Yes, guys, it is the only place in our code, where we
697 may make it not affecting IPv4.
698 The rest of code is protocol independent,
699 and I do not like idea to uglify IPv4.
701 Actually, all the idea behind IPV6_PKTOPTIONS
702 looks not very well thought. For now we latch
703 options, received in the last packet, enqueued
704 by tcp. Feel free to propose better solution.
709 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
710 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
712 opt_skb
= skb_clone(skb
, GFP_ATOMIC
);
714 if (sk
->sk_state
== DCCP_OPEN
) { /* Fast path */
715 if (dccp_rcv_established(sk
, skb
, dccp_hdr(skb
), skb
->len
))
718 /* XXX This is where we would goto ipv6_pktoptions. */
719 __kfree_skb(opt_skb
);
725 * Step 3: Process LISTEN state
726 * If S.state == LISTEN,
727 * If P.type == Request or P contains a valid Init Cookie option,
728 * (* Must scan the packet's options to check for Init
729 * Cookies. Only Init Cookies are processed here,
730 * however; other options are processed in Step 8. This
731 * scan need only be performed if the endpoint uses Init
733 * (* Generate a new socket and switch to that socket *)
734 * Set S := new socket for this port pair
736 * Choose S.ISS (initial seqno) or set from Init Cookies
737 * Initialize S.GAR := S.ISS
738 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
739 * Continue with S.state == RESPOND
740 * (* A Response packet will be generated in Step 11 *)
742 * Generate Reset(No Connection) unless P.type == Reset
743 * Drop packet and return
745 * NOTE: the check for the packet types is done in
746 * dccp_rcv_state_process
748 if (sk
->sk_state
== DCCP_LISTEN
) {
749 struct sock
*nsk
= dccp_v6_hnd_req(sk
, skb
);
754 * Queue it on the new socket if the new socket is active,
755 * otherwise we just shortcircuit this and continue with
759 if (dccp_child_process(sk
, nsk
, skb
))
762 __kfree_skb(opt_skb
);
767 if (dccp_rcv_state_process(sk
, skb
, dccp_hdr(skb
), skb
->len
))
770 /* XXX This is where we would goto ipv6_pktoptions. */
771 __kfree_skb(opt_skb
);
776 dccp_v6_ctl_send_reset(sk
, skb
);
779 __kfree_skb(opt_skb
);
784 static int dccp_v6_rcv(struct sk_buff
*skb
)
786 const struct dccp_hdr
*dh
;
790 /* Step 1: Check header basics */
792 if (dccp_invalid_packet(skb
))
795 /* Step 1: If header checksum is incorrect, drop packet and return. */
796 if (dccp_v6_csum_finish(skb
, &ipv6_hdr(skb
)->saddr
,
797 &ipv6_hdr(skb
)->daddr
)) {
798 DCCP_WARN("dropped packet with invalid checksum\n");
804 DCCP_SKB_CB(skb
)->dccpd_seq
= dccp_hdr_seq(dh
);
805 DCCP_SKB_CB(skb
)->dccpd_type
= dh
->dccph_type
;
807 if (dccp_packet_without_ack(skb
))
808 DCCP_SKB_CB(skb
)->dccpd_ack_seq
= DCCP_PKT_WITHOUT_ACK_SEQ
;
810 DCCP_SKB_CB(skb
)->dccpd_ack_seq
= dccp_hdr_ack_seq(skb
);
813 * Look up flow ID in table and get corresponding socket */
814 sk
= __inet6_lookup_skb(&dccp_hashinfo
, skb
,
815 dh
->dccph_sport
, dh
->dccph_dport
);
821 dccp_pr_debug("failed to look up flow ID in table and "
822 "get corresponding socket\n");
828 * ... or S.state == TIMEWAIT,
829 * Generate Reset(No Connection) unless P.type == Reset
830 * Drop packet and return
832 if (sk
->sk_state
== DCCP_TIME_WAIT
) {
833 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
834 inet_twsk_put(inet_twsk(sk
));
839 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
840 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
841 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
843 min_cov
= dccp_sk(sk
)->dccps_pcrlen
;
844 if (dh
->dccph_cscov
&& (min_cov
== 0 || dh
->dccph_cscov
< min_cov
)) {
845 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
846 dh
->dccph_cscov
, min_cov
);
847 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
848 goto discard_and_relse
;
851 if (!xfrm6_policy_check(sk
, XFRM_POLICY_IN
, skb
))
852 goto discard_and_relse
;
854 return sk_receive_skb(sk
, skb
, 1) ? -1 : 0;
857 if (!xfrm6_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
862 * Generate Reset(No Connection) unless P.type == Reset
863 * Drop packet and return
865 if (dh
->dccph_type
!= DCCP_PKT_RESET
) {
866 DCCP_SKB_CB(skb
)->dccpd_reset_code
=
867 DCCP_RESET_CODE_NO_CONNECTION
;
868 dccp_v6_ctl_send_reset(sk
, skb
);
880 static int dccp_v6_connect(struct sock
*sk
, struct sockaddr
*uaddr
,
883 struct sockaddr_in6
*usin
= (struct sockaddr_in6
*)uaddr
;
884 struct inet_connection_sock
*icsk
= inet_csk(sk
);
885 struct inet_sock
*inet
= inet_sk(sk
);
886 struct ipv6_pinfo
*np
= inet6_sk(sk
);
887 struct dccp_sock
*dp
= dccp_sk(sk
);
888 struct in6_addr
*saddr
= NULL
, *final_p
= NULL
, final
;
890 struct dst_entry
*dst
;
894 dp
->dccps_role
= DCCP_ROLE_CLIENT
;
896 if (addr_len
< SIN6_LEN_RFC2133
)
899 if (usin
->sin6_family
!= AF_INET6
)
900 return -EAFNOSUPPORT
;
902 memset(&fl
, 0, sizeof(fl
));
905 fl
.fl6_flowlabel
= usin
->sin6_flowinfo
& IPV6_FLOWINFO_MASK
;
906 IP6_ECN_flow_init(fl
.fl6_flowlabel
);
907 if (fl
.fl6_flowlabel
& IPV6_FLOWLABEL_MASK
) {
908 struct ip6_flowlabel
*flowlabel
;
909 flowlabel
= fl6_sock_lookup(sk
, fl
.fl6_flowlabel
);
910 if (flowlabel
== NULL
)
912 ipv6_addr_copy(&usin
->sin6_addr
, &flowlabel
->dst
);
913 fl6_sock_release(flowlabel
);
917 * connect() to INADDR_ANY means loopback (BSD'ism).
919 if (ipv6_addr_any(&usin
->sin6_addr
))
920 usin
->sin6_addr
.s6_addr
[15] = 1;
922 addr_type
= ipv6_addr_type(&usin
->sin6_addr
);
924 if (addr_type
& IPV6_ADDR_MULTICAST
)
927 if (addr_type
& IPV6_ADDR_LINKLOCAL
) {
928 if (addr_len
>= sizeof(struct sockaddr_in6
) &&
929 usin
->sin6_scope_id
) {
930 /* If interface is set while binding, indices
933 if (sk
->sk_bound_dev_if
&&
934 sk
->sk_bound_dev_if
!= usin
->sin6_scope_id
)
937 sk
->sk_bound_dev_if
= usin
->sin6_scope_id
;
940 /* Connect to link-local address requires an interface */
941 if (!sk
->sk_bound_dev_if
)
945 ipv6_addr_copy(&np
->daddr
, &usin
->sin6_addr
);
946 np
->flow_label
= fl
.fl6_flowlabel
;
951 if (addr_type
== IPV6_ADDR_MAPPED
) {
952 u32 exthdrlen
= icsk
->icsk_ext_hdr_len
;
953 struct sockaddr_in sin
;
955 SOCK_DEBUG(sk
, "connect: ipv4 mapped\n");
957 if (__ipv6_only_sock(sk
))
960 sin
.sin_family
= AF_INET
;
961 sin
.sin_port
= usin
->sin6_port
;
962 sin
.sin_addr
.s_addr
= usin
->sin6_addr
.s6_addr32
[3];
964 icsk
->icsk_af_ops
= &dccp_ipv6_mapped
;
965 sk
->sk_backlog_rcv
= dccp_v4_do_rcv
;
967 err
= dccp_v4_connect(sk
, (struct sockaddr
*)&sin
, sizeof(sin
));
969 icsk
->icsk_ext_hdr_len
= exthdrlen
;
970 icsk
->icsk_af_ops
= &dccp_ipv6_af_ops
;
971 sk
->sk_backlog_rcv
= dccp_v6_do_rcv
;
974 ipv6_addr_set_v4mapped(inet
->inet_saddr
, &np
->saddr
);
975 ipv6_addr_set_v4mapped(inet
->inet_rcv_saddr
, &np
->rcv_saddr
);
980 if (!ipv6_addr_any(&np
->rcv_saddr
))
981 saddr
= &np
->rcv_saddr
;
983 fl
.proto
= IPPROTO_DCCP
;
984 ipv6_addr_copy(&fl
.fl6_dst
, &np
->daddr
);
985 ipv6_addr_copy(&fl
.fl6_src
, saddr
? saddr
: &np
->saddr
);
986 fl
.oif
= sk
->sk_bound_dev_if
;
987 fl
.fl_ip_dport
= usin
->sin6_port
;
988 fl
.fl_ip_sport
= inet
->inet_sport
;
989 security_sk_classify_flow(sk
, &fl
);
991 if (np
->opt
!= NULL
&& np
->opt
->srcrt
!= NULL
) {
992 const struct rt0_hdr
*rt0
= (struct rt0_hdr
*)np
->opt
->srcrt
;
994 ipv6_addr_copy(&final
, &fl
.fl6_dst
);
995 ipv6_addr_copy(&fl
.fl6_dst
, rt0
->addr
);
999 err
= ip6_dst_lookup(sk
, &dst
, &fl
);
1004 ipv6_addr_copy(&fl
.fl6_dst
, final_p
);
1006 err
= __xfrm_lookup(sock_net(sk
), &dst
, &fl
, sk
, XFRM_LOOKUP_WAIT
);
1008 if (err
== -EREMOTE
)
1009 err
= ip6_dst_blackhole(sk
, &dst
, &fl
);
1014 if (saddr
== NULL
) {
1015 saddr
= &fl
.fl6_src
;
1016 ipv6_addr_copy(&np
->rcv_saddr
, saddr
);
1019 /* set the source address */
1020 ipv6_addr_copy(&np
->saddr
, saddr
);
1021 inet
->inet_rcv_saddr
= LOOPBACK4_IPV6
;
1023 __ip6_dst_store(sk
, dst
, NULL
, NULL
);
1025 icsk
->icsk_ext_hdr_len
= 0;
1026 if (np
->opt
!= NULL
)
1027 icsk
->icsk_ext_hdr_len
= (np
->opt
->opt_flen
+
1028 np
->opt
->opt_nflen
);
1030 inet
->inet_dport
= usin
->sin6_port
;
1032 dccp_set_state(sk
, DCCP_REQUESTING
);
1033 err
= inet6_hash_connect(&dccp_death_row
, sk
);
1037 dp
->dccps_iss
= secure_dccpv6_sequence_number(np
->saddr
.s6_addr32
,
1038 np
->daddr
.s6_addr32
,
1041 err
= dccp_connect(sk
);
1048 dccp_set_state(sk
, DCCP_CLOSED
);
1051 inet
->inet_dport
= 0;
1052 sk
->sk_route_caps
= 0;
1056 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops
= {
1057 .queue_xmit
= inet6_csk_xmit
,
1058 .send_check
= dccp_v6_send_check
,
1059 .rebuild_header
= inet6_sk_rebuild_header
,
1060 .conn_request
= dccp_v6_conn_request
,
1061 .syn_recv_sock
= dccp_v6_request_recv_sock
,
1062 .net_header_len
= sizeof(struct ipv6hdr
),
1063 .setsockopt
= ipv6_setsockopt
,
1064 .getsockopt
= ipv6_getsockopt
,
1065 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1066 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1067 .bind_conflict
= inet6_csk_bind_conflict
,
1068 #ifdef CONFIG_COMPAT
1069 .compat_setsockopt
= compat_ipv6_setsockopt
,
1070 .compat_getsockopt
= compat_ipv6_getsockopt
,
1075 * DCCP over IPv4 via INET6 API
1077 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped
= {
1078 .queue_xmit
= ip_queue_xmit
,
1079 .send_check
= dccp_v4_send_check
,
1080 .rebuild_header
= inet_sk_rebuild_header
,
1081 .conn_request
= dccp_v6_conn_request
,
1082 .syn_recv_sock
= dccp_v6_request_recv_sock
,
1083 .net_header_len
= sizeof(struct iphdr
),
1084 .setsockopt
= ipv6_setsockopt
,
1085 .getsockopt
= ipv6_getsockopt
,
1086 .addr2sockaddr
= inet6_csk_addr2sockaddr
,
1087 .sockaddr_len
= sizeof(struct sockaddr_in6
),
1088 #ifdef CONFIG_COMPAT
1089 .compat_setsockopt
= compat_ipv6_setsockopt
,
1090 .compat_getsockopt
= compat_ipv6_getsockopt
,
1094 /* NOTE: A lot of things set to zero explicitly by call to
1095 * sk_alloc() so need not be done here.
1097 static int dccp_v6_init_sock(struct sock
*sk
)
1099 static __u8 dccp_v6_ctl_sock_initialized
;
1100 int err
= dccp_init_sock(sk
, dccp_v6_ctl_sock_initialized
);
1103 if (unlikely(!dccp_v6_ctl_sock_initialized
))
1104 dccp_v6_ctl_sock_initialized
= 1;
1105 inet_csk(sk
)->icsk_af_ops
= &dccp_ipv6_af_ops
;
1111 static void dccp_v6_destroy_sock(struct sock
*sk
)
1113 dccp_destroy_sock(sk
);
1114 inet6_destroy_sock(sk
);
1117 static struct timewait_sock_ops dccp6_timewait_sock_ops
= {
1118 .twsk_obj_size
= sizeof(struct dccp6_timewait_sock
),
1121 static struct proto dccp_v6_prot
= {
1123 .owner
= THIS_MODULE
,
1124 .close
= dccp_close
,
1125 .connect
= dccp_v6_connect
,
1126 .disconnect
= dccp_disconnect
,
1127 .ioctl
= dccp_ioctl
,
1128 .init
= dccp_v6_init_sock
,
1129 .setsockopt
= dccp_setsockopt
,
1130 .getsockopt
= dccp_getsockopt
,
1131 .sendmsg
= dccp_sendmsg
,
1132 .recvmsg
= dccp_recvmsg
,
1133 .backlog_rcv
= dccp_v6_do_rcv
,
1134 .hash
= dccp_v6_hash
,
1135 .unhash
= inet_unhash
,
1136 .accept
= inet_csk_accept
,
1137 .get_port
= inet_csk_get_port
,
1138 .shutdown
= dccp_shutdown
,
1139 .destroy
= dccp_v6_destroy_sock
,
1140 .orphan_count
= &dccp_orphan_count
,
1141 .max_header
= MAX_DCCP_HEADER
,
1142 .obj_size
= sizeof(struct dccp6_sock
),
1143 .slab_flags
= SLAB_DESTROY_BY_RCU
,
1144 .rsk_prot
= &dccp6_request_sock_ops
,
1145 .twsk_prot
= &dccp6_timewait_sock_ops
,
1146 .h
.hashinfo
= &dccp_hashinfo
,
1147 #ifdef CONFIG_COMPAT
1148 .compat_setsockopt
= compat_dccp_setsockopt
,
1149 .compat_getsockopt
= compat_dccp_getsockopt
,
1153 static const struct inet6_protocol dccp_v6_protocol
= {
1154 .handler
= dccp_v6_rcv
,
1155 .err_handler
= dccp_v6_err
,
1156 .flags
= INET6_PROTO_NOPOLICY
| INET6_PROTO_FINAL
,
1159 static const struct proto_ops inet6_dccp_ops
= {
1161 .owner
= THIS_MODULE
,
1162 .release
= inet6_release
,
1164 .connect
= inet_stream_connect
,
1165 .socketpair
= sock_no_socketpair
,
1166 .accept
= inet_accept
,
1167 .getname
= inet6_getname
,
1169 .ioctl
= inet6_ioctl
,
1170 .listen
= inet_dccp_listen
,
1171 .shutdown
= inet_shutdown
,
1172 .setsockopt
= sock_common_setsockopt
,
1173 .getsockopt
= sock_common_getsockopt
,
1174 .sendmsg
= inet_sendmsg
,
1175 .recvmsg
= sock_common_recvmsg
,
1176 .mmap
= sock_no_mmap
,
1177 .sendpage
= sock_no_sendpage
,
1178 #ifdef CONFIG_COMPAT
1179 .compat_setsockopt
= compat_sock_common_setsockopt
,
1180 .compat_getsockopt
= compat_sock_common_getsockopt
,
1184 static struct inet_protosw dccp_v6_protosw
= {
1186 .protocol
= IPPROTO_DCCP
,
1187 .prot
= &dccp_v6_prot
,
1188 .ops
= &inet6_dccp_ops
,
1189 .flags
= INET_PROTOSW_ICSK
,
1192 static int __net_init
dccp_v6_init_net(struct net
*net
)
1196 err
= inet_ctl_sock_create(&net
->dccp
.v6_ctl_sk
, PF_INET6
,
1197 SOCK_DCCP
, IPPROTO_DCCP
, net
);
1201 static void __net_exit
dccp_v6_exit_net(struct net
*net
)
1203 inet_ctl_sock_destroy(net
->dccp
.v6_ctl_sk
);
1206 static struct pernet_operations dccp_v6_ops
= {
1207 .init
= dccp_v6_init_net
,
1208 .exit
= dccp_v6_exit_net
,
1211 static int __init
dccp_v6_init(void)
1213 int err
= proto_register(&dccp_v6_prot
, 1);
1218 err
= inet6_add_protocol(&dccp_v6_protocol
, IPPROTO_DCCP
);
1220 goto out_unregister_proto
;
1222 inet6_register_protosw(&dccp_v6_protosw
);
1224 err
= register_pernet_subsys(&dccp_v6_ops
);
1226 goto out_destroy_ctl_sock
;
1230 out_destroy_ctl_sock
:
1231 inet6_del_protocol(&dccp_v6_protocol
, IPPROTO_DCCP
);
1232 inet6_unregister_protosw(&dccp_v6_protosw
);
1233 out_unregister_proto
:
1234 proto_unregister(&dccp_v6_prot
);
1238 static void __exit
dccp_v6_exit(void)
1240 unregister_pernet_subsys(&dccp_v6_ops
);
1241 inet6_del_protocol(&dccp_v6_protocol
, IPPROTO_DCCP
);
1242 inet6_unregister_protosw(&dccp_v6_protosw
);
1243 proto_unregister(&dccp_v6_prot
);
1246 module_init(dccp_v6_init
);
1247 module_exit(dccp_v6_exit
);
1250 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1251 * values directly, Also cover the case where the protocol is not specified,
1252 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1254 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6
, 33, 6);
1255 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6
, 0, 6);
1256 MODULE_LICENSE("GPL");
1257 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1258 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");