net/dccp/ipv6.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      DCCP over IPv6
   4  *      Linux INET6 implementation
   5  *
   6  *      Based on net/dccp6/ipv6.c
   7  *
   8  *      Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/random.h>
  13 #include <linux/slab.h>
  14 #include <linux/xfrm.h>
  15 #include <linux/string.h>
  16
  17 #include <net/addrconf.h>
  18 #include <net/inet_common.h>
  19 #include <net/inet_hashtables.h>
  20 #include <net/inet_sock.h>
  21 #include <net/inet6_connection_sock.h>
  22 #include <net/inet6_hashtables.h>
  23 #include <net/ip6_route.h>
  24 #include <net/ipv6.h>
  25 #include <net/protocol.h>
  26 #include <net/transp_v6.h>
  27 #include <net/ip6_checksum.h>
  28 #include <net/xfrm.h>
  29 #include <net/secure_seq.h>
  30 #include <net/netns/generic.h>
  31 #include <net/sock.h>
  32
  33 #include "dccp.h"
  34 #include "ipv6.h"
  35 #include "feat.h"
  36
  37 struct dccp_v6_pernet {
  38         struct sock *v6_ctl_sk;
  39 };
  40
  41 static unsigned int dccp_v6_pernet_id __read_mostly;
  42
  43 /* The per-net v6_ctl_sk is used for sending RSTs and ACKs */
  44
  45 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped;
  46 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops;
  47
  48 /* add pseudo-header to DCCP checksum stored in skb->csum */
  49 static inline __sum16 dccp_v6_csum_finish(struct sk_buff *skb,
  50                                       const struct in6_addr *saddr,
  51                                       const struct in6_addr *daddr)
  52 {
  53         return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum);
  54 }
  55
  56 static inline void dccp_v6_send_check(struct sock *sk, struct sk_buff *skb)
  57 {
  58         struct ipv6_pinfo *np = inet6_sk(sk);
  59         struct dccp_hdr *dh = dccp_hdr(skb);
  60
  61         dccp_csum_outgoing(skb);
  62         dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &sk->sk_v6_daddr);
  63 }
  64
  65 static inline __u64 dccp_v6_init_sequence(struct sk_buff *skb)
  66 {
  67         return secure_dccpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
  68                                              ipv6_hdr(skb)->saddr.s6_addr32,
  69                                              dccp_hdr(skb)->dccph_dport,
  70                                              dccp_hdr(skb)->dccph_sport     );
  71
  72 }
  73
  74 static int dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
  75                         u8 type, u8 code, int offset, __be32 info)
  76 {
  77         const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data;
  78         const struct dccp_hdr *dh;
  79         struct dccp_sock *dp;
  80         struct ipv6_pinfo *np;
  81         struct sock *sk;
  82         int err;
  83         __u64 seq;
  84         struct net *net = dev_net(skb->dev);
  85
  86         /* Only need dccph_dport & dccph_sport which are the first
  87          * 4 bytes in dccp header.
  88          * Our caller (icmpv6_notify()) already pulled 8 bytes for us.
  89          */
  90         BUILD_BUG_ON(offsetofend(struct dccp_hdr, dccph_sport) > 8);
  91         BUILD_BUG_ON(offsetofend(struct dccp_hdr, dccph_dport) > 8);
  92         dh = (struct dccp_hdr *)(skb->data + offset);
  93
  94         sk = __inet6_lookup_established(net, &dccp_hashinfo,
  95                                         &hdr->daddr, dh->dccph_dport,
  96                                         &hdr->saddr, ntohs(dh->dccph_sport),
  97                                         inet6_iif(skb), 0);
  98
  99         if (!sk) {
 100                 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev),
 101                                   ICMP6_MIB_INERRORS);
 102                 return -ENOENT;
 103         }
 104
 105         if (sk->sk_state == DCCP_TIME_WAIT) {
 106                 inet_twsk_put(inet_twsk(sk));
 107                 return 0;
 108         }
 109         seq = dccp_hdr_seq(dh);
 110         if (sk->sk_state == DCCP_NEW_SYN_RECV) {
 111                 dccp_req_err(sk, seq);
 112                 return 0;
 113         }
 114
 115         bh_lock_sock(sk);
 116         if (sock_owned_by_user(sk))
 117                 __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS);
 118
 119         if (sk->sk_state == DCCP_CLOSED)
 120                 goto out;
 121
 122         dp = dccp_sk(sk);
 123         if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) &&
 124             !between48(seq, dp->dccps_awl, dp->dccps_awh)) {
 125                 __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS);
 126                 goto out;
 127         }
 128
 129         np = inet6_sk(sk);
 130
 131         if (type == NDISC_REDIRECT) {
 132                 if (!sock_owned_by_user(sk)) {
 133                         struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);
 134
 135                         if (dst)
 136                                 dst->ops->redirect(dst, sk, skb);
 137                 }
 138                 goto out;
 139         }
 140
 141         if (type == ICMPV6_PKT_TOOBIG) {
 142                 struct dst_entry *dst = NULL;
 143
 144                 if (!ip6_sk_accept_pmtu(sk))
 145                         goto out;
 146
 147                 if (sock_owned_by_user(sk))
 148                         goto out;
 149                 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
 150                         goto out;
 151
 152                 dst = inet6_csk_update_pmtu(sk, ntohl(info));
 153                 if (!dst)
 154                         goto out;
 155
 156                 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst))
 157                         dccp_sync_mss(sk, dst_mtu(dst));
 158                 goto out;
 159         }
 160
 161         icmpv6_err_convert(type, code, &err);
 162
 163         /* Might be for an request_sock */
 164         switch (sk->sk_state) {
 165         case DCCP_REQUESTING:
 166         case DCCP_RESPOND:  /* Cannot happen.
 167                                It can, it SYNs are crossed. --ANK */
 168                 if (!sock_owned_by_user(sk)) {
 169                         __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS);
 170                         sk->sk_err = err;
 171                         /*
 172                          * Wake people up to see the error
 173                          * (see connect in sock.c)
 174                          */
 175                         sk_error_report(sk);
 176                         dccp_done(sk);
 177                 } else
 178                         sk->sk_err_soft = err;
 179                 goto out;
 180         }
 181
 182         if (!sock_owned_by_user(sk) && np->recverr) {
 183                 sk->sk_err = err;
 184                 sk_error_report(sk);
 185         } else
 186                 sk->sk_err_soft = err;
 187
 188 out:
 189         bh_unlock_sock(sk);
 190         sock_put(sk);
 191         return 0;
 192 }
 193
 194
 195 static int dccp_v6_send_response(const struct sock *sk, struct request_sock *req)
 196 {
 197         struct inet_request_sock *ireq = inet_rsk(req);
 198         struct ipv6_pinfo *np = inet6_sk(sk);
 199         struct sk_buff *skb;
 200         struct in6_addr *final_p, final;
 201         struct flowi6 fl6;
 202         int err = -1;
 203         struct dst_entry *dst;
 204
 205         memset(&fl6, 0, sizeof(fl6));
 206         fl6.flowi6_proto = IPPROTO_DCCP;
 207         fl6.daddr = ireq->ir_v6_rmt_addr;
 208         fl6.saddr = ireq->ir_v6_loc_addr;
 209         fl6.flowlabel = 0;
 210         fl6.flowi6_oif = ireq->ir_iif;
 211         fl6.fl6_dport = ireq->ir_rmt_port;
 212         fl6.fl6_sport = htons(ireq->ir_num);
 213         security_req_classify_flow(req, flowi6_to_flowi_common(&fl6));
 214
 215
 216         rcu_read_lock();
 217         final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt), &final);
 218         rcu_read_unlock();
 219
 220         dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 221         if (IS_ERR(dst)) {
 222                 err = PTR_ERR(dst);
 223                 dst = NULL;
 224                 goto done;
 225         }
 226
 227         skb = dccp_make_response(sk, dst, req);
 228         if (skb != NULL) {
 229                 struct dccp_hdr *dh = dccp_hdr(skb);
 230                 struct ipv6_txoptions *opt;
 231
 232                 dh->dccph_checksum = dccp_v6_csum_finish(skb,
 233                                                          &ireq->ir_v6_loc_addr,
 234                                                          &ireq->ir_v6_rmt_addr);
 235                 fl6.daddr = ireq->ir_v6_rmt_addr;
 236                 rcu_read_lock();
 237                 opt = ireq->ipv6_opt;
 238                 if (!opt)
 239                         opt = rcu_dereference(np->opt);
 240                 err = ip6_xmit(sk, skb, &fl6, sk->sk_mark, opt, np->tclass,
 241                                sk->sk_priority);
 242                 rcu_read_unlock();
 243                 err = net_xmit_eval(err);
 244         }
 245
 246 done:
 247         dst_release(dst);
 248         return err;
 249 }
 250
 251 static void dccp_v6_reqsk_destructor(struct request_sock *req)
 252 {
 253         dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
 254         kfree(inet_rsk(req)->ipv6_opt);
 255         kfree_skb(inet_rsk(req)->pktopts);
 256 }
 257
 258 static void dccp_v6_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb)
 259 {
 260         const struct ipv6hdr *rxip6h;
 261         struct sk_buff *skb;
 262         struct flowi6 fl6;
 263         struct net *net = dev_net(skb_dst(rxskb)->dev);
 264         struct dccp_v6_pernet *pn;
 265         struct sock *ctl_sk;
 266         struct dst_entry *dst;
 267
 268         if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET)
 269                 return;
 270
 271         if (!ipv6_unicast_destination(rxskb))
 272                 return;
 273
 274         pn = net_generic(net, dccp_v6_pernet_id);
 275         ctl_sk = pn->v6_ctl_sk;
 276         skb = dccp_ctl_make_reset(ctl_sk, rxskb);
 277         if (skb == NULL)
 278                 return;
 279
 280         rxip6h = ipv6_hdr(rxskb);
 281         dccp_hdr(skb)->dccph_checksum = dccp_v6_csum_finish(skb, &rxip6h->saddr,
 282                                                             &rxip6h->daddr);
 283
 284         memset(&fl6, 0, sizeof(fl6));
 285         fl6.daddr = rxip6h->saddr;
 286         fl6.saddr = rxip6h->daddr;
 287
 288         fl6.flowi6_proto = IPPROTO_DCCP;
 289         fl6.flowi6_oif = inet6_iif(rxskb);
 290         fl6.fl6_dport = dccp_hdr(skb)->dccph_dport;
 291         fl6.fl6_sport = dccp_hdr(skb)->dccph_sport;
 292         security_skb_classify_flow(rxskb, flowi6_to_flowi_common(&fl6));
 293
 294         /* sk = NULL, but it is safe for now. RST socket required. */
 295         dst = ip6_dst_lookup_flow(sock_net(ctl_sk), ctl_sk, &fl6, NULL);
 296         if (!IS_ERR(dst)) {
 297                 skb_dst_set(skb, dst);
 298                 ip6_xmit(ctl_sk, skb, &fl6, 0, NULL, 0, 0);
 299                 DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
 300                 DCCP_INC_STATS(DCCP_MIB_OUTRSTS);
 301                 return;
 302         }
 303
 304         kfree_skb(skb);
 305 }
 306
 307 static struct request_sock_ops dccp6_request_sock_ops = {
 308         .family         = AF_INET6,
 309         .obj_size       = sizeof(struct dccp6_request_sock),
 310         .rtx_syn_ack    = dccp_v6_send_response,
 311         .send_ack       = dccp_reqsk_send_ack,
 312         .destructor     = dccp_v6_reqsk_destructor,
 313         .send_reset     = dccp_v6_ctl_send_reset,
 314         .syn_ack_timeout = dccp_syn_ack_timeout,
 315 };
 316
 317 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
 318 {
 319         struct request_sock *req;
 320         struct dccp_request_sock *dreq;
 321         struct inet_request_sock *ireq;
 322         struct ipv6_pinfo *np = inet6_sk(sk);
 323         const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
 324         struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
 325
 326         if (skb->protocol == htons(ETH_P_IP))
 327                 return dccp_v4_conn_request(sk, skb);
 328
 329         if (!ipv6_unicast_destination(skb))
 330                 return 0;       /* discard, don't send a reset here */
 331
 332         if (ipv6_addr_v4mapped(&ipv6_hdr(skb)->saddr)) {
 333                 __IP6_INC_STATS(sock_net(sk), NULL, IPSTATS_MIB_INHDRERRORS);
 334                 return 0;
 335         }
 336
 337         if (dccp_bad_service_code(sk, service)) {
 338                 dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
 339                 goto drop;
 340         }
 341         /*
 342          * There are no SYN attacks on IPv6, yet...
 343          */
 344         dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY;
 345         if (inet_csk_reqsk_queue_is_full(sk))
 346                 goto drop;
 347
 348         if (sk_acceptq_is_full(sk))
 349                 goto drop;
 350
 351         req = inet_reqsk_alloc(&dccp6_request_sock_ops, sk, true);
 352         if (req == NULL)
 353                 goto drop;
 354
 355         if (dccp_reqsk_init(req, dccp_sk(sk), skb))
 356                 goto drop_and_free;
 357
 358         dreq = dccp_rsk(req);
 359         if (dccp_parse_options(sk, dreq, skb))
 360                 goto drop_and_free;
 361
 362         if (security_inet_conn_request(sk, skb, req))
 363                 goto drop_and_free;
 364
 365         ireq = inet_rsk(req);
 366         ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
 367         ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
 368         ireq->ireq_family = AF_INET6;
 369         ireq->ir_mark = inet_request_mark(sk, skb);
 370
 371         if (ipv6_opt_accepted(sk, skb, IP6CB(skb)) ||
 372             np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
 373             np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
 374                 refcount_inc(&skb->users);
 375                 ireq->pktopts = skb;
 376         }
 377         ireq->ir_iif = sk->sk_bound_dev_if;
 378
 379         /* So that link locals have meaning */
 380         if (!sk->sk_bound_dev_if &&
 381             ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
 382                 ireq->ir_iif = inet6_iif(skb);
 383
 384         /*
 385          * Step 3: Process LISTEN state
 386          *
 387          *   Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
 388          *
 389          * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child().
 390          */
 391         dreq->dreq_isr     = dcb->dccpd_seq;
 392         dreq->dreq_gsr     = dreq->dreq_isr;
 393         dreq->dreq_iss     = dccp_v6_init_sequence(skb);
 394         dreq->dreq_gss     = dreq->dreq_iss;
 395         dreq->dreq_service = service;
 396
 397         if (dccp_v6_send_response(sk, req))
 398                 goto drop_and_free;
 399
 400         inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
 401         reqsk_put(req);
 402         return 0;
 403
 404 drop_and_free:
 405         reqsk_free(req);
 406 drop:
 407         __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS);
 408         return -1;
 409 }
 410
 411 static struct sock *dccp_v6_request_recv_sock(const struct sock *sk,
 412                                               struct sk_buff *skb,
 413                                               struct request_sock *req,
 414                                               struct dst_entry *dst,
 415                                               struct request_sock *req_unhash,
 416                                               bool *own_req)
 417 {
 418         struct inet_request_sock *ireq = inet_rsk(req);
 419         struct ipv6_pinfo *newnp;
 420         const struct ipv6_pinfo *np = inet6_sk(sk);
 421         struct ipv6_txoptions *opt;
 422         struct inet_sock *newinet;
 423         struct dccp6_sock *newdp6;
 424         struct sock *newsk;
 425
 426         if (skb->protocol == htons(ETH_P_IP)) {
 427                 /*
 428                  *      v6 mapped
 429                  */
 430                 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst,
 431                                                   req_unhash, own_req);
 432                 if (newsk == NULL)
 433                         return NULL;
 434
 435                 newdp6 = (struct dccp6_sock *)newsk;
 436                 newinet = inet_sk(newsk);
 437                 newinet->pinet6 = &newdp6->inet6;
 438                 newnp = inet6_sk(newsk);
 439
 440                 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 441
 442                 newnp->saddr = newsk->sk_v6_rcv_saddr;
 443
 444                 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
 445                 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
 446                 newnp->pktoptions  = NULL;
 447                 newnp->opt         = NULL;
 448                 newnp->ipv6_mc_list = NULL;
 449                 newnp->ipv6_ac_list = NULL;
 450                 newnp->ipv6_fl_list = NULL;
 451                 newnp->mcast_oif   = inet_iif(skb);
 452                 newnp->mcast_hops  = ip_hdr(skb)->ttl;
 453
 454                 /*
 455                  * No need to charge this sock to the relevant IPv6 refcnt debug socks count
 456                  * here, dccp_create_openreq_child now does this for us, see the comment in
 457                  * that function for the gory details. -acme
 458                  */
 459
 460                 /* It is tricky place. Until this moment IPv4 tcp
 461                    worked with IPv6 icsk.icsk_af_ops.
 462                    Sync it now.
 463                  */
 464                 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
 465
 466                 return newsk;
 467         }
 468
 469
 470         if (sk_acceptq_is_full(sk))
 471                 goto out_overflow;
 472
 473         if (!dst) {
 474                 struct flowi6 fl6;
 475
 476                 dst = inet6_csk_route_req(sk, &fl6, req, IPPROTO_DCCP);
 477                 if (!dst)
 478                         goto out;
 479         }
 480
 481         newsk = dccp_create_openreq_child(sk, req, skb);
 482         if (newsk == NULL)
 483                 goto out_nonewsk;
 484
 485         /*
 486          * No need to charge this sock to the relevant IPv6 refcnt debug socks
 487          * count here, dccp_create_openreq_child now does this for us, see the
 488          * comment in that function for the gory details. -acme
 489          */
 490
 491         ip6_dst_store(newsk, dst, NULL, NULL);
 492         newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
 493                                                       NETIF_F_TSO);
 494         newdp6 = (struct dccp6_sock *)newsk;
 495         newinet = inet_sk(newsk);
 496         newinet->pinet6 = &newdp6->inet6;
 497         newnp = inet6_sk(newsk);
 498
 499         memcpy(newnp, np, sizeof(struct ipv6_pinfo));
 500
 501         newsk->sk_v6_daddr      = ireq->ir_v6_rmt_addr;
 502         newnp->saddr            = ireq->ir_v6_loc_addr;
 503         newsk->sk_v6_rcv_saddr  = ireq->ir_v6_loc_addr;
 504         newsk->sk_bound_dev_if  = ireq->ir_iif;
 505
 506         /* Now IPv6 options...
 507
 508            First: no IPv4 options.
 509          */
 510         newinet->inet_opt = NULL;
 511
 512         /* Clone RX bits */
 513         newnp->rxopt.all = np->rxopt.all;
 514
 515         newnp->ipv6_mc_list = NULL;
 516         newnp->ipv6_ac_list = NULL;
 517         newnp->ipv6_fl_list = NULL;
 518         newnp->pktoptions = NULL;
 519         newnp->opt        = NULL;
 520         newnp->mcast_oif  = inet6_iif(skb);
 521         newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
 522
 523         /*
 524          * Clone native IPv6 options from listening socket (if any)
 525          *
 526          * Yes, keeping reference count would be much more clever, but we make
 527          * one more one thing there: reattach optmem to newsk.
 528          */
 529         opt = ireq->ipv6_opt;
 530         if (!opt)
 531                 opt = rcu_dereference(np->opt);
 532         if (opt) {
 533                 opt = ipv6_dup_options(newsk, opt);
 534                 RCU_INIT_POINTER(newnp->opt, opt);
 535         }
 536         inet_csk(newsk)->icsk_ext_hdr_len = 0;
 537         if (opt)
 538                 inet_csk(newsk)->icsk_ext_hdr_len = opt->opt_nflen +
 539                                                     opt->opt_flen;
 540
 541         dccp_sync_mss(newsk, dst_mtu(dst));
 542
 543         newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
 544         newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
 545
 546         if (__inet_inherit_port(sk, newsk) < 0) {
 547                 inet_csk_prepare_forced_close(newsk);
 548                 dccp_done(newsk);
 549                 goto out;
 550         }
 551         *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash), NULL);
 552         /* Clone pktoptions received with SYN, if we own the req */
 553         if (*own_req && ireq->pktopts) {
 554                 newnp->pktoptions = skb_clone(ireq->pktopts, GFP_ATOMIC);
 555                 consume_skb(ireq->pktopts);
 556                 ireq->pktopts = NULL;
 557                 if (newnp->pktoptions)
 558                         skb_set_owner_r(newnp->pktoptions, newsk);
 559         }
 560
 561         return newsk;
 562
 563 out_overflow:
 564         __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
 565 out_nonewsk:
 566         dst_release(dst);
 567 out:
 568         __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS);
 569         return NULL;
 570 }
 571
 572 /* The socket must have it's spinlock held when we get
 573  * here.
 574  *
 575  * We have a potential double-lock case here, so even when
 576  * doing backlog processing we use the BH locking scheme.
 577  * This is because we cannot sleep with the original spinlock
 578  * held.
 579  */
 580 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
 581 {
 582         struct ipv6_pinfo *np = inet6_sk(sk);
 583         struct sk_buff *opt_skb = NULL;
 584
 585         /* Imagine: socket is IPv6. IPv4 packet arrives,
 586            goes to IPv4 receive handler and backlogged.
 587            From backlog it always goes here. Kerboom...
 588            Fortunately, dccp_rcv_established and rcv_established
 589            handle them correctly, but it is not case with
 590            dccp_v6_hnd_req and dccp_v6_ctl_send_reset().   --ANK
 591          */
 592
 593         if (skb->protocol == htons(ETH_P_IP))
 594                 return dccp_v4_do_rcv(sk, skb);
 595
 596         if (sk_filter(sk, skb))
 597                 goto discard;
 598
 599         /*
 600          * socket locking is here for SMP purposes as backlog rcv is currently
 601          * called with bh processing disabled.
 602          */
 603
 604         /* Do Stevens' IPV6_PKTOPTIONS.
 605
 606            Yes, guys, it is the only place in our code, where we
 607            may make it not affecting IPv4.
 608            The rest of code is protocol independent,
 609            and I do not like idea to uglify IPv4.
 610
 611            Actually, all the idea behind IPV6_PKTOPTIONS
 612            looks not very well thought. For now we latch
 613            options, received in the last packet, enqueued
 614            by tcp. Feel free to propose better solution.
 615                                                --ANK (980728)
 616          */
 617         if (np->rxopt.all)
 618                 opt_skb = skb_clone(skb, GFP_ATOMIC);
 619
 620         if (sk->sk_state == DCCP_OPEN) { /* Fast path */
 621                 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
 622                         goto reset;
 623                 if (opt_skb)
 624                         goto ipv6_pktoptions;
 625                 return 0;
 626         }
 627
 628         /*
 629          *  Step 3: Process LISTEN state
 630          *     If S.state == LISTEN,
 631          *       If P.type == Request or P contains a valid Init Cookie option,
 632          *            (* Must scan the packet's options to check for Init
 633          *               Cookies.  Only Init Cookies are processed here,
 634          *               however; other options are processed in Step 8.  This
 635          *               scan need only be performed if the endpoint uses Init
 636          *               Cookies *)
 637          *            (* Generate a new socket and switch to that socket *)
 638          *            Set S := new socket for this port pair
 639          *            S.state = RESPOND
 640          *            Choose S.ISS (initial seqno) or set from Init Cookies
 641          *            Initialize S.GAR := S.ISS
 642          *            Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
 643          *            Continue with S.state == RESPOND
 644          *            (* A Response packet will be generated in Step 11 *)
 645          *       Otherwise,
 646          *            Generate Reset(No Connection) unless P.type == Reset
 647          *            Drop packet and return
 648          *
 649          * NOTE: the check for the packet types is done in
 650          *       dccp_rcv_state_process
 651          */
 652
 653         if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
 654                 goto reset;
 655         if (opt_skb)
 656                 goto ipv6_pktoptions;
 657         return 0;
 658
 659 reset:
 660         dccp_v6_ctl_send_reset(sk, skb);
 661 discard:
 662         if (opt_skb != NULL)
 663                 __kfree_skb(opt_skb);
 664         kfree_skb(skb);
 665         return 0;
 666
 667 /* Handling IPV6_PKTOPTIONS skb the similar
 668  * way it's done for net/ipv6/tcp_ipv6.c
 669  */
 670 ipv6_pktoptions:
 671         if (!((1 << sk->sk_state) & (DCCPF_CLOSED | DCCPF_LISTEN))) {
 672                 if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
 673                         np->mcast_oif = inet6_iif(opt_skb);
 674                 if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
 675                         np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit;
 676                 if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass)
 677                         np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb));
 678                 if (np->repflow)
 679                         np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb));
 680                 if (ipv6_opt_accepted(sk, opt_skb,
 681                                       &DCCP_SKB_CB(opt_skb)->header.h6)) {
 682                         skb_set_owner_r(opt_skb, sk);
 683                         memmove(IP6CB(opt_skb),
 684                                 &DCCP_SKB_CB(opt_skb)->header.h6,
 685                                 sizeof(struct inet6_skb_parm));
 686                         opt_skb = xchg(&np->pktoptions, opt_skb);
 687                 } else {
 688                         __kfree_skb(opt_skb);
 689                         opt_skb = xchg(&np->pktoptions, NULL);
 690                 }
 691         }
 692
 693         kfree_skb(opt_skb);
 694         return 0;
 695 }
 696
 697 static int dccp_v6_rcv(struct sk_buff *skb)
 698 {
 699         const struct dccp_hdr *dh;
 700         bool refcounted;
 701         struct sock *sk;
 702         int min_cov;
 703
 704         /* Step 1: Check header basics */
 705
 706         if (dccp_invalid_packet(skb))
 707                 goto discard_it;
 708
 709         /* Step 1: If header checksum is incorrect, drop packet and return. */
 710         if (dccp_v6_csum_finish(skb, &ipv6_hdr(skb)->saddr,
 711                                      &ipv6_hdr(skb)->daddr)) {
 712                 DCCP_WARN("dropped packet with invalid checksum\n");
 713                 goto discard_it;
 714         }
 715
 716         dh = dccp_hdr(skb);
 717
 718         DCCP_SKB_CB(skb)->dccpd_seq  = dccp_hdr_seq(dh);
 719         DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
 720
 721         if (dccp_packet_without_ack(skb))
 722                 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
 723         else
 724                 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
 725
 726 lookup:
 727         sk = __inet6_lookup_skb(&dccp_hashinfo, skb, __dccp_hdr_len(dh),
 728                                 dh->dccph_sport, dh->dccph_dport,
 729                                 inet6_iif(skb), 0, &refcounted);
 730         if (!sk) {
 731                 dccp_pr_debug("failed to look up flow ID in table and "
 732                               "get corresponding socket\n");
 733                 goto no_dccp_socket;
 734         }
 735
 736         /*
 737          * Step 2:
 738          *      ... or S.state == TIMEWAIT,
 739          *              Generate Reset(No Connection) unless P.type == Reset
 740          *              Drop packet and return
 741          */
 742         if (sk->sk_state == DCCP_TIME_WAIT) {
 743                 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
 744                 inet_twsk_put(inet_twsk(sk));
 745                 goto no_dccp_socket;
 746         }
 747
 748         if (sk->sk_state == DCCP_NEW_SYN_RECV) {
 749                 struct request_sock *req = inet_reqsk(sk);
 750                 struct sock *nsk;
 751
 752                 sk = req->rsk_listener;
 753                 if (unlikely(sk->sk_state != DCCP_LISTEN)) {
 754                         inet_csk_reqsk_queue_drop_and_put(sk, req);
 755                         goto lookup;
 756                 }
 757                 sock_hold(sk);
 758                 refcounted = true;
 759                 nsk = dccp_check_req(sk, skb, req);
 760                 if (!nsk) {
 761                         reqsk_put(req);
 762                         goto discard_and_relse;
 763                 }
 764                 if (nsk == sk) {
 765                         reqsk_put(req);
 766                 } else if (dccp_child_process(sk, nsk, skb)) {
 767                         dccp_v6_ctl_send_reset(sk, skb);
 768                         goto discard_and_relse;
 769                 } else {
 770                         sock_put(sk);
 771                         return 0;
 772                 }
 773         }
 774         /*
 775          * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
 776          *      o if MinCsCov = 0, only packets with CsCov = 0 are accepted
 777          *      o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
 778          */
 779         min_cov = dccp_sk(sk)->dccps_pcrlen;
 780         if (dh->dccph_cscov  &&  (min_cov == 0 || dh->dccph_cscov < min_cov))  {
 781                 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
 782                               dh->dccph_cscov, min_cov);
 783                 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
 784                 goto discard_and_relse;
 785         }
 786
 787         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
 788                 goto discard_and_relse;
 789
 790         return __sk_receive_skb(sk, skb, 1, dh->dccph_doff * 4,
 791                                 refcounted) ? -1 : 0;
 792
 793 no_dccp_socket:
 794         if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
 795                 goto discard_it;
 796         /*
 797          * Step 2:
 798          *      If no socket ...
 799          *              Generate Reset(No Connection) unless P.type == Reset
 800          *              Drop packet and return
 801          */
 802         if (dh->dccph_type != DCCP_PKT_RESET) {
 803                 DCCP_SKB_CB(skb)->dccpd_reset_code =
 804                                         DCCP_RESET_CODE_NO_CONNECTION;
 805                 dccp_v6_ctl_send_reset(sk, skb);
 806         }
 807
 808 discard_it:
 809         kfree_skb(skb);
 810         return 0;
 811
 812 discard_and_relse:
 813         if (refcounted)
 814                 sock_put(sk);
 815         goto discard_it;
 816 }
 817
 818 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 819                            int addr_len)
 820 {
 821         struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
 822         struct inet_connection_sock *icsk = inet_csk(sk);
 823         struct inet_sock *inet = inet_sk(sk);
 824         struct ipv6_pinfo *np = inet6_sk(sk);
 825         struct dccp_sock *dp = dccp_sk(sk);
 826         struct in6_addr *saddr = NULL, *final_p, final;
 827         struct ipv6_txoptions *opt;
 828         struct flowi6 fl6;
 829         struct dst_entry *dst;
 830         int addr_type;
 831         int err;
 832
 833         dp->dccps_role = DCCP_ROLE_CLIENT;
 834
 835         if (addr_len < SIN6_LEN_RFC2133)
 836                 return -EINVAL;
 837
 838         if (usin->sin6_family != AF_INET6)
 839                 return -EAFNOSUPPORT;
 840
 841         memset(&fl6, 0, sizeof(fl6));
 842
 843         if (np->sndflow) {
 844                 fl6.flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
 845                 IP6_ECN_flow_init(fl6.flowlabel);
 846                 if (fl6.flowlabel & IPV6_FLOWLABEL_MASK) {
 847                         struct ip6_flowlabel *flowlabel;
 848                         flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
 849                         if (IS_ERR(flowlabel))
 850                                 return -EINVAL;
 851                         fl6_sock_release(flowlabel);
 852                 }
 853         }
 854         /*
 855          * connect() to INADDR_ANY means loopback (BSD'ism).
 856          */
 857         if (ipv6_addr_any(&usin->sin6_addr))
 858                 usin->sin6_addr.s6_addr[15] = 1;
 859
 860         addr_type = ipv6_addr_type(&usin->sin6_addr);
 861
 862         if (addr_type & IPV6_ADDR_MULTICAST)
 863                 return -ENETUNREACH;
 864
 865         if (addr_type & IPV6_ADDR_LINKLOCAL) {
 866                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 867                     usin->sin6_scope_id) {
 868                         /* If interface is set while binding, indices
 869                          * must coincide.
 870                          */
 871                         if (sk->sk_bound_dev_if &&
 872                             sk->sk_bound_dev_if != usin->sin6_scope_id)
 873                                 return -EINVAL;
 874
 875                         sk->sk_bound_dev_if = usin->sin6_scope_id;
 876                 }
 877
 878                 /* Connect to link-local address requires an interface */
 879                 if (!sk->sk_bound_dev_if)
 880                         return -EINVAL;
 881         }
 882
 883         sk->sk_v6_daddr = usin->sin6_addr;
 884         np->flow_label = fl6.flowlabel;
 885
 886         /*
 887          * DCCP over IPv4
 888          */
 889         if (addr_type == IPV6_ADDR_MAPPED) {
 890                 u32 exthdrlen = icsk->icsk_ext_hdr_len;
 891                 struct sockaddr_in sin;
 892
 893                 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
 894
 895                 if (__ipv6_only_sock(sk))
 896                         return -ENETUNREACH;
 897
 898                 sin.sin_family = AF_INET;
 899                 sin.sin_port = usin->sin6_port;
 900                 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
 901
 902                 icsk->icsk_af_ops = &dccp_ipv6_mapped;
 903                 sk->sk_backlog_rcv = dccp_v4_do_rcv;
 904
 905                 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
 906                 if (err) {
 907                         icsk->icsk_ext_hdr_len = exthdrlen;
 908                         icsk->icsk_af_ops = &dccp_ipv6_af_ops;
 909                         sk->sk_backlog_rcv = dccp_v6_do_rcv;
 910                         goto failure;
 911                 }
 912                 np->saddr = sk->sk_v6_rcv_saddr;
 913                 return err;
 914         }
 915
 916         if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr))
 917                 saddr = &sk->sk_v6_rcv_saddr;
 918
 919         fl6.flowi6_proto = IPPROTO_DCCP;
 920         fl6.daddr = sk->sk_v6_daddr;
 921         fl6.saddr = saddr ? *saddr : np->saddr;
 922         fl6.flowi6_oif = sk->sk_bound_dev_if;
 923         fl6.fl6_dport = usin->sin6_port;
 924         fl6.fl6_sport = inet->inet_sport;
 925         security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
 926
 927         opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
 928         final_p = fl6_update_dst(&fl6, opt, &final);
 929
 930         dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 931         if (IS_ERR(dst)) {
 932                 err = PTR_ERR(dst);
 933                 goto failure;
 934         }
 935
 936         if (saddr == NULL) {
 937                 saddr = &fl6.saddr;
 938                 sk->sk_v6_rcv_saddr = *saddr;
 939         }
 940
 941         /* set the source address */
 942         np->saddr = *saddr;
 943         inet->inet_rcv_saddr = LOOPBACK4_IPV6;
 944
 945         ip6_dst_store(sk, dst, NULL, NULL);
 946
 947         icsk->icsk_ext_hdr_len = 0;
 948         if (opt)
 949                 icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
 950
 951         inet->inet_dport = usin->sin6_port;
 952
 953         dccp_set_state(sk, DCCP_REQUESTING);
 954         err = inet6_hash_connect(&dccp_death_row, sk);
 955         if (err)
 956                 goto late_failure;
 957
 958         dp->dccps_iss = secure_dccpv6_sequence_number(np->saddr.s6_addr32,
 959                                                       sk->sk_v6_daddr.s6_addr32,
 960                                                       inet->inet_sport,
 961                                                       inet->inet_dport);
 962         err = dccp_connect(sk);
 963         if (err)
 964                 goto late_failure;
 965
 966         return 0;
 967
 968 late_failure:
 969         dccp_set_state(sk, DCCP_CLOSED);
 970         __sk_dst_reset(sk);
 971 failure:
 972         inet->inet_dport = 0;
 973         sk->sk_route_caps = 0;
 974         return err;
 975 }
 976
 977 static const struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
 978         .queue_xmit        = inet6_csk_xmit,
 979         .send_check        = dccp_v6_send_check,
 980         .rebuild_header    = inet6_sk_rebuild_header,
 981         .conn_request      = dccp_v6_conn_request,
 982         .syn_recv_sock     = dccp_v6_request_recv_sock,
 983         .net_header_len    = sizeof(struct ipv6hdr),
 984         .setsockopt        = ipv6_setsockopt,
 985         .getsockopt        = ipv6_getsockopt,
 986         .addr2sockaddr     = inet6_csk_addr2sockaddr,
 987         .sockaddr_len      = sizeof(struct sockaddr_in6),
 988 };
 989
 990 /*
 991  *      DCCP over IPv4 via INET6 API
 992  */
 993 static const struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
 994         .queue_xmit        = ip_queue_xmit,
 995         .send_check        = dccp_v4_send_check,
 996         .rebuild_header    = inet_sk_rebuild_header,
 997         .conn_request      = dccp_v6_conn_request,
 998         .syn_recv_sock     = dccp_v6_request_recv_sock,
 999         .net_header_len    = sizeof(struct iphdr),
1000         .setsockopt        = ipv6_setsockopt,
1001         .getsockopt        = ipv6_getsockopt,
1002         .addr2sockaddr     = inet6_csk_addr2sockaddr,
1003         .sockaddr_len      = sizeof(struct sockaddr_in6),
1004 };
1005
1006 /* NOTE: A lot of things set to zero explicitly by call to
1007  *       sk_alloc() so need not be done here.
1008  */
1009 static int dccp_v6_init_sock(struct sock *sk)
1010 {
1011         static __u8 dccp_v6_ctl_sock_initialized;
1012         int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1013
1014         if (err == 0) {
1015                 if (unlikely(!dccp_v6_ctl_sock_initialized))
1016                         dccp_v6_ctl_sock_initialized = 1;
1017                 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1018         }
1019
1020         return err;
1021 }
1022
1023 static void dccp_v6_destroy_sock(struct sock *sk)
1024 {
1025         dccp_destroy_sock(sk);
1026         inet6_destroy_sock(sk);
1027 }
1028
1029 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1030         .twsk_obj_size  = sizeof(struct dccp6_timewait_sock),
1031 };
1032
1033 static struct proto dccp_v6_prot = {
1034         .name              = "DCCPv6",
1035         .owner             = THIS_MODULE,
1036         .close             = dccp_close,
1037         .connect           = dccp_v6_connect,
1038         .disconnect        = dccp_disconnect,
1039         .ioctl             = dccp_ioctl,
1040         .init              = dccp_v6_init_sock,
1041         .setsockopt        = dccp_setsockopt,
1042         .getsockopt        = dccp_getsockopt,
1043         .sendmsg           = dccp_sendmsg,
1044         .recvmsg           = dccp_recvmsg,
1045         .backlog_rcv       = dccp_v6_do_rcv,
1046         .hash              = inet6_hash,
1047         .unhash            = inet_unhash,
1048         .accept            = inet_csk_accept,
1049         .get_port          = inet_csk_get_port,
1050         .shutdown          = dccp_shutdown,
1051         .destroy           = dccp_v6_destroy_sock,
1052         .orphan_count      = &dccp_orphan_count,
1053         .max_header        = MAX_DCCP_HEADER,
1054         .obj_size          = sizeof(struct dccp6_sock),
1055         .slab_flags        = SLAB_TYPESAFE_BY_RCU,
1056         .rsk_prot          = &dccp6_request_sock_ops,
1057         .twsk_prot         = &dccp6_timewait_sock_ops,
1058         .h.hashinfo        = &dccp_hashinfo,
1059 };
1060
1061 static const struct inet6_protocol dccp_v6_protocol = {
1062         .handler        = dccp_v6_rcv,
1063         .err_handler    = dccp_v6_err,
1064         .flags          = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1065 };
1066
1067 static const struct proto_ops inet6_dccp_ops = {
1068         .family            = PF_INET6,
1069         .owner             = THIS_MODULE,
1070         .release           = inet6_release,
1071         .bind              = inet6_bind,
1072         .connect           = inet_stream_connect,
1073         .socketpair        = sock_no_socketpair,
1074         .accept            = inet_accept,
1075         .getname           = inet6_getname,
1076         .poll              = dccp_poll,
1077         .ioctl             = inet6_ioctl,
1078         .gettstamp         = sock_gettstamp,
1079         .listen            = inet_dccp_listen,
1080         .shutdown          = inet_shutdown,
1081         .setsockopt        = sock_common_setsockopt,
1082         .getsockopt        = sock_common_getsockopt,
1083         .sendmsg           = inet_sendmsg,
1084         .recvmsg           = sock_common_recvmsg,
1085         .mmap              = sock_no_mmap,
1086         .sendpage          = sock_no_sendpage,
1087 #ifdef CONFIG_COMPAT
1088         .compat_ioctl      = inet6_compat_ioctl,
1089 #endif
1090 };
1091
1092 static struct inet_protosw dccp_v6_protosw = {
1093         .type           = SOCK_DCCP,
1094         .protocol       = IPPROTO_DCCP,
1095         .prot           = &dccp_v6_prot,
1096         .ops            = &inet6_dccp_ops,
1097         .flags          = INET_PROTOSW_ICSK,
1098 };
1099
1100 static int __net_init dccp_v6_init_net(struct net *net)
1101 {
1102         struct dccp_v6_pernet *pn = net_generic(net, dccp_v6_pernet_id);
1103
1104         if (dccp_hashinfo.bhash == NULL)
1105                 return -ESOCKTNOSUPPORT;
1106
1107         return inet_ctl_sock_create(&pn->v6_ctl_sk, PF_INET6,
1108                                     SOCK_DCCP, IPPROTO_DCCP, net);
1109 }
1110
1111 static void __net_exit dccp_v6_exit_net(struct net *net)
1112 {
1113         struct dccp_v6_pernet *pn = net_generic(net, dccp_v6_pernet_id);
1114
1115         inet_ctl_sock_destroy(pn->v6_ctl_sk);
1116 }
1117
1118 static void __net_exit dccp_v6_exit_batch(struct list_head *net_exit_list)
1119 {
1120         inet_twsk_purge(&dccp_hashinfo, AF_INET6);
1121 }
1122
1123 static struct pernet_operations dccp_v6_ops = {
1124         .init   = dccp_v6_init_net,
1125         .exit   = dccp_v6_exit_net,
1126         .exit_batch = dccp_v6_exit_batch,
1127         .id     = &dccp_v6_pernet_id,
1128         .size   = sizeof(struct dccp_v6_pernet),
1129 };
1130
1131 static int __init dccp_v6_init(void)
1132 {
1133         int err = proto_register(&dccp_v6_prot, 1);
1134
1135         if (err)
1136                 goto out;
1137
1138         inet6_register_protosw(&dccp_v6_protosw);
1139
1140         err = register_pernet_subsys(&dccp_v6_ops);
1141         if (err)
1142                 goto out_destroy_ctl_sock;
1143
1144         err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1145         if (err)
1146                 goto out_unregister_proto;
1147
1148 out:
1149         return err;
1150 out_unregister_proto:
1151         unregister_pernet_subsys(&dccp_v6_ops);
1152 out_destroy_ctl_sock:
1153         inet6_unregister_protosw(&dccp_v6_protosw);
1154         proto_unregister(&dccp_v6_prot);
1155         goto out;
1156 }
1157
1158 static void __exit dccp_v6_exit(void)
1159 {
1160         inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1161         unregister_pernet_subsys(&dccp_v6_ops);
1162         inet6_unregister_protosw(&dccp_v6_protosw);
1163         proto_unregister(&dccp_v6_prot);
1164 }
1165
1166 module_init(dccp_v6_init);
1167 module_exit(dccp_v6_exit);
1168
1169 /*
1170  * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1171  * values directly, Also cover the case where the protocol is not specified,
1172  * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1173  */
1174 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 33, 6);
1175 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 0, 6);
1176 MODULE_LICENSE("GPL");
1177 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1178 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");