Arnaldo Carvalho de Melo | 3df80d9 | 2005-12-13 23:24:53 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * DCCP over IPv6 |
| 3 | * Linux INET6 implementation |
| 4 | * |
| 5 | * Based on net/dccp6/ipv6.c |
| 6 | * |
| 7 | * Arnaldo Carvalho de Melo <acme@ghostprotocols.net> |
| 8 | * |
| 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. |
| 13 | */ |
| 14 | |
| 15 | #include <linux/config.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/random.h> |
| 18 | #include <linux/xfrm.h> |
| 19 | |
| 20 | #include <net/addrconf.h> |
| 21 | #include <net/inet_common.h> |
| 22 | #include <net/inet_hashtables.h> |
| 23 | #include <net/inet6_connection_sock.h> |
| 24 | #include <net/inet6_hashtables.h> |
| 25 | #include <net/ip6_route.h> |
| 26 | #include <net/ipv6.h> |
| 27 | #include <net/protocol.h> |
| 28 | #include <net/transp_v6.h> |
| 29 | #include <net/xfrm.h> |
| 30 | |
| 31 | #include "dccp.h" |
| 32 | #include "ipv6.h" |
| 33 | |
| 34 | static void dccp_v6_ctl_send_reset(struct sk_buff *skb); |
| 35 | static void dccp_v6_reqsk_send_ack(struct sk_buff *skb, |
| 36 | struct request_sock *req); |
| 37 | static void dccp_v6_send_check(struct sock *sk, int len, struct sk_buff *skb); |
| 38 | |
| 39 | static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); |
| 40 | |
| 41 | static struct inet_connection_sock_af_ops dccp_ipv6_mapped; |
| 42 | static struct inet_connection_sock_af_ops dccp_ipv6_af_ops; |
| 43 | |
| 44 | static int dccp_v6_get_port(struct sock *sk, unsigned short snum) |
| 45 | { |
| 46 | return inet_csk_get_port(&dccp_hashinfo, sk, snum, |
| 47 | inet6_csk_bind_conflict); |
| 48 | } |
| 49 | |
| 50 | static void dccp_v6_hash(struct sock *sk) |
| 51 | { |
| 52 | if (sk->sk_state != DCCP_CLOSED) { |
| 53 | if (inet_csk(sk)->icsk_af_ops == &dccp_ipv6_mapped) { |
| 54 | dccp_prot.hash(sk); |
| 55 | return; |
| 56 | } |
| 57 | local_bh_disable(); |
| 58 | __inet6_hash(&dccp_hashinfo, sk); |
| 59 | local_bh_enable(); |
| 60 | } |
| 61 | } |
| 62 | |
| 63 | static inline u16 dccp_v6_check(struct dccp_hdr *dh, int len, |
| 64 | struct in6_addr *saddr, |
| 65 | struct in6_addr *daddr, |
| 66 | unsigned long base) |
| 67 | { |
| 68 | return csum_ipv6_magic(saddr, daddr, len, IPPROTO_DCCP, base); |
| 69 | } |
| 70 | |
| 71 | static __u32 dccp_v6_init_sequence(struct sock *sk, struct sk_buff *skb) |
| 72 | { |
| 73 | const struct dccp_hdr *dh = dccp_hdr(skb); |
| 74 | |
| 75 | if (skb->protocol == htons(ETH_P_IPV6)) |
| 76 | return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32, |
| 77 | skb->nh.ipv6h->saddr.s6_addr32, |
| 78 | dh->dccph_dport, |
| 79 | dh->dccph_sport); |
| 80 | else |
| 81 | return secure_dccp_sequence_number(skb->nh.iph->daddr, |
| 82 | skb->nh.iph->saddr, |
| 83 | dh->dccph_dport, |
| 84 | dh->dccph_sport); |
| 85 | } |
| 86 | |
| 87 | static int __dccp_v6_check_established(struct sock *sk, const __u16 lport, |
| 88 | struct inet_timewait_sock **twp) |
| 89 | { |
| 90 | struct inet_sock *inet = inet_sk(sk); |
| 91 | const struct ipv6_pinfo *np = inet6_sk(sk); |
| 92 | const struct in6_addr *daddr = &np->rcv_saddr; |
| 93 | const struct in6_addr *saddr = &np->daddr; |
| 94 | const int dif = sk->sk_bound_dev_if; |
| 95 | const u32 ports = INET_COMBINED_PORTS(inet->dport, lport); |
| 96 | const unsigned int hash = inet6_ehashfn(daddr, inet->num, |
| 97 | saddr, inet->dport); |
| 98 | struct inet_ehash_bucket *head = inet_ehash_bucket(&dccp_hashinfo, hash); |
| 99 | struct sock *sk2; |
| 100 | const struct hlist_node *node; |
| 101 | struct inet_timewait_sock *tw; |
| 102 | |
| 103 | prefetch(head->chain.first); |
| 104 | write_lock(&head->lock); |
| 105 | |
| 106 | /* Check TIME-WAIT sockets first. */ |
| 107 | sk_for_each(sk2, node, &(head + dccp_hashinfo.ehash_size)->chain) { |
| 108 | const struct inet6_timewait_sock *tw6 = inet6_twsk(sk2); |
| 109 | |
| 110 | tw = inet_twsk(sk2); |
| 111 | |
| 112 | if(*((__u32 *)&(tw->tw_dport)) == ports && |
| 113 | sk2->sk_family == PF_INET6 && |
| 114 | ipv6_addr_equal(&tw6->tw_v6_daddr, saddr) && |
| 115 | ipv6_addr_equal(&tw6->tw_v6_rcv_saddr, daddr) && |
| 116 | sk2->sk_bound_dev_if == sk->sk_bound_dev_if) |
| 117 | goto not_unique; |
| 118 | } |
| 119 | tw = NULL; |
| 120 | |
| 121 | /* And established part... */ |
| 122 | sk_for_each(sk2, node, &head->chain) { |
| 123 | if (INET6_MATCH(sk2, hash, saddr, daddr, ports, dif)) |
| 124 | goto not_unique; |
| 125 | } |
| 126 | |
| 127 | BUG_TRAP(sk_unhashed(sk)); |
| 128 | __sk_add_node(sk, &head->chain); |
| 129 | sk->sk_hash = hash; |
| 130 | sock_prot_inc_use(sk->sk_prot); |
| 131 | write_unlock(&head->lock); |
| 132 | |
| 133 | if (twp) { |
| 134 | *twp = tw; |
| 135 | NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED); |
| 136 | } else if (tw) { |
| 137 | /* Silly. Should hash-dance instead... */ |
| 138 | inet_twsk_deschedule(tw, &dccp_death_row); |
| 139 | NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED); |
| 140 | |
| 141 | inet_twsk_put(tw); |
| 142 | } |
| 143 | return 0; |
| 144 | |
| 145 | not_unique: |
| 146 | write_unlock(&head->lock); |
| 147 | return -EADDRNOTAVAIL; |
| 148 | } |
| 149 | |
| 150 | static inline u32 dccp_v6_port_offset(const struct sock *sk) |
| 151 | { |
| 152 | const struct inet_sock *inet = inet_sk(sk); |
| 153 | const struct ipv6_pinfo *np = inet6_sk(sk); |
| 154 | |
| 155 | return secure_tcpv6_port_ephemeral(np->rcv_saddr.s6_addr32, |
| 156 | np->daddr.s6_addr32, |
| 157 | inet->dport); |
| 158 | } |
| 159 | |
| 160 | static int dccp_v6_hash_connect(struct sock *sk) |
| 161 | { |
| 162 | const unsigned short snum = inet_sk(sk)->num; |
| 163 | struct inet_bind_hashbucket *head; |
| 164 | struct inet_bind_bucket *tb; |
| 165 | int ret; |
| 166 | |
| 167 | if (snum == 0) { |
| 168 | int low = sysctl_local_port_range[0]; |
| 169 | int high = sysctl_local_port_range[1]; |
| 170 | int range = high - low; |
| 171 | int i; |
| 172 | int port; |
| 173 | static u32 hint; |
| 174 | u32 offset = hint + dccp_v6_port_offset(sk); |
| 175 | struct hlist_node *node; |
| 176 | struct inet_timewait_sock *tw = NULL; |
| 177 | |
| 178 | local_bh_disable(); |
| 179 | for (i = 1; i <= range; i++) { |
| 180 | port = low + (i + offset) % range; |
| 181 | head = &dccp_hashinfo.bhash[inet_bhashfn(port, |
| 182 | dccp_hashinfo.bhash_size)]; |
| 183 | spin_lock(&head->lock); |
| 184 | |
| 185 | /* Does not bother with rcv_saddr checks, |
| 186 | * because the established check is already |
| 187 | * unique enough. |
| 188 | */ |
| 189 | inet_bind_bucket_for_each(tb, node, &head->chain) { |
| 190 | if (tb->port == port) { |
| 191 | BUG_TRAP(!hlist_empty(&tb->owners)); |
| 192 | if (tb->fastreuse >= 0) |
| 193 | goto next_port; |
| 194 | if (!__dccp_v6_check_established(sk, |
| 195 | port, |
| 196 | &tw)) |
| 197 | goto ok; |
| 198 | goto next_port; |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | tb = inet_bind_bucket_create(dccp_hashinfo.bind_bucket_cachep, |
| 203 | head, port); |
| 204 | if (!tb) { |
| 205 | spin_unlock(&head->lock); |
| 206 | break; |
| 207 | } |
| 208 | tb->fastreuse = -1; |
| 209 | goto ok; |
| 210 | |
| 211 | next_port: |
| 212 | spin_unlock(&head->lock); |
| 213 | } |
| 214 | local_bh_enable(); |
| 215 | |
| 216 | return -EADDRNOTAVAIL; |
| 217 | ok: |
| 218 | hint += i; |
| 219 | |
| 220 | /* Head lock still held and bh's disabled */ |
| 221 | inet_bind_hash(sk, tb, port); |
| 222 | if (sk_unhashed(sk)) { |
| 223 | inet_sk(sk)->sport = htons(port); |
| 224 | __inet6_hash(&dccp_hashinfo, sk); |
| 225 | } |
| 226 | spin_unlock(&head->lock); |
| 227 | |
| 228 | if (tw) { |
| 229 | inet_twsk_deschedule(tw, &dccp_death_row); |
| 230 | inet_twsk_put(tw); |
| 231 | } |
| 232 | |
| 233 | ret = 0; |
| 234 | goto out; |
| 235 | } |
| 236 | |
| 237 | head = &dccp_hashinfo.bhash[inet_bhashfn(snum, |
| 238 | dccp_hashinfo.bhash_size)]; |
| 239 | tb = inet_csk(sk)->icsk_bind_hash; |
| 240 | spin_lock_bh(&head->lock); |
| 241 | |
| 242 | if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) { |
| 243 | __inet6_hash(&dccp_hashinfo, sk); |
| 244 | spin_unlock_bh(&head->lock); |
| 245 | return 0; |
| 246 | } else { |
| 247 | spin_unlock(&head->lock); |
| 248 | /* No definite answer... Walk to established hash table */ |
| 249 | ret = __dccp_v6_check_established(sk, snum, NULL); |
| 250 | out: |
| 251 | local_bh_enable(); |
| 252 | return ret; |
| 253 | } |
| 254 | } |
| 255 | |
| 256 | static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr, |
| 257 | int addr_len) |
| 258 | { |
| 259 | struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; |
| 260 | struct inet_sock *inet = inet_sk(sk); |
| 261 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 262 | struct dccp_sock *dp = dccp_sk(sk); |
| 263 | struct in6_addr *saddr = NULL, *final_p = NULL, final; |
| 264 | struct flowi fl; |
| 265 | struct dst_entry *dst; |
| 266 | int addr_type; |
| 267 | int err; |
| 268 | |
| 269 | dp->dccps_role = DCCP_ROLE_CLIENT; |
| 270 | |
| 271 | if (addr_len < SIN6_LEN_RFC2133) |
| 272 | return -EINVAL; |
| 273 | |
| 274 | if (usin->sin6_family != AF_INET6) |
| 275 | return -EAFNOSUPPORT; |
| 276 | |
| 277 | memset(&fl, 0, sizeof(fl)); |
| 278 | |
| 279 | if (np->sndflow) { |
| 280 | fl.fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK; |
| 281 | IP6_ECN_flow_init(fl.fl6_flowlabel); |
| 282 | if (fl.fl6_flowlabel & IPV6_FLOWLABEL_MASK) { |
| 283 | struct ip6_flowlabel *flowlabel; |
| 284 | flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel); |
| 285 | if (flowlabel == NULL) |
| 286 | return -EINVAL; |
| 287 | ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst); |
| 288 | fl6_sock_release(flowlabel); |
| 289 | } |
| 290 | } |
| 291 | |
| 292 | /* |
| 293 | * connect() to INADDR_ANY means loopback (BSD'ism). |
| 294 | */ |
| 295 | |
| 296 | if (ipv6_addr_any(&usin->sin6_addr)) |
| 297 | usin->sin6_addr.s6_addr[15] = 0x1; |
| 298 | |
| 299 | addr_type = ipv6_addr_type(&usin->sin6_addr); |
| 300 | |
| 301 | if(addr_type & IPV6_ADDR_MULTICAST) |
| 302 | return -ENETUNREACH; |
| 303 | |
| 304 | if (addr_type & IPV6_ADDR_LINKLOCAL) { |
| 305 | if (addr_len >= sizeof(struct sockaddr_in6) && |
| 306 | usin->sin6_scope_id) { |
| 307 | /* If interface is set while binding, indices |
| 308 | * must coincide. |
| 309 | */ |
| 310 | if (sk->sk_bound_dev_if && |
| 311 | sk->sk_bound_dev_if != usin->sin6_scope_id) |
| 312 | return -EINVAL; |
| 313 | |
| 314 | sk->sk_bound_dev_if = usin->sin6_scope_id; |
| 315 | } |
| 316 | |
| 317 | /* Connect to link-local address requires an interface */ |
| 318 | if (!sk->sk_bound_dev_if) |
| 319 | return -EINVAL; |
| 320 | } |
| 321 | |
| 322 | ipv6_addr_copy(&np->daddr, &usin->sin6_addr); |
| 323 | np->flow_label = fl.fl6_flowlabel; |
| 324 | |
| 325 | /* |
| 326 | * DCCP over IPv4 |
| 327 | */ |
| 328 | |
| 329 | if (addr_type == IPV6_ADDR_MAPPED) { |
| 330 | u32 exthdrlen = dp->dccps_ext_header_len; |
| 331 | struct sockaddr_in sin; |
| 332 | |
| 333 | SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); |
| 334 | |
| 335 | if (__ipv6_only_sock(sk)) |
| 336 | return -ENETUNREACH; |
| 337 | |
| 338 | sin.sin_family = AF_INET; |
| 339 | sin.sin_port = usin->sin6_port; |
| 340 | sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; |
| 341 | |
| 342 | inet_csk(sk)->icsk_af_ops = &dccp_ipv6_mapped; |
| 343 | sk->sk_backlog_rcv = dccp_v4_do_rcv; |
| 344 | |
| 345 | err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); |
| 346 | |
| 347 | if (err) { |
| 348 | dp->dccps_ext_header_len = exthdrlen; |
| 349 | inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops; |
| 350 | sk->sk_backlog_rcv = dccp_v6_do_rcv; |
| 351 | goto failure; |
| 352 | } else { |
| 353 | ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF), |
| 354 | inet->saddr); |
| 355 | ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF), |
| 356 | inet->rcv_saddr); |
| 357 | } |
| 358 | |
| 359 | return err; |
| 360 | } |
| 361 | |
| 362 | if (!ipv6_addr_any(&np->rcv_saddr)) |
| 363 | saddr = &np->rcv_saddr; |
| 364 | |
| 365 | fl.proto = IPPROTO_DCCP; |
| 366 | ipv6_addr_copy(&fl.fl6_dst, &np->daddr); |
| 367 | ipv6_addr_copy(&fl.fl6_src, saddr ? saddr : &np->saddr); |
| 368 | fl.oif = sk->sk_bound_dev_if; |
| 369 | fl.fl_ip_dport = usin->sin6_port; |
| 370 | fl.fl_ip_sport = inet->sport; |
| 371 | |
| 372 | if (np->opt && np->opt->srcrt) { |
| 373 | struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt; |
| 374 | ipv6_addr_copy(&final, &fl.fl6_dst); |
| 375 | ipv6_addr_copy(&fl.fl6_dst, rt0->addr); |
| 376 | final_p = &final; |
| 377 | } |
| 378 | |
| 379 | err = ip6_dst_lookup(sk, &dst, &fl); |
| 380 | if (err) |
| 381 | goto failure; |
| 382 | if (final_p) |
| 383 | ipv6_addr_copy(&fl.fl6_dst, final_p); |
| 384 | |
| 385 | if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) |
| 386 | goto failure; |
| 387 | |
| 388 | if (saddr == NULL) { |
| 389 | saddr = &fl.fl6_src; |
| 390 | ipv6_addr_copy(&np->rcv_saddr, saddr); |
| 391 | } |
| 392 | |
| 393 | /* set the source address */ |
| 394 | ipv6_addr_copy(&np->saddr, saddr); |
| 395 | inet->rcv_saddr = LOOPBACK4_IPV6; |
| 396 | |
| 397 | ip6_dst_store(sk, dst, NULL); |
| 398 | |
| 399 | dp->dccps_ext_header_len = 0; |
| 400 | if (np->opt) |
| 401 | dp->dccps_ext_header_len = np->opt->opt_flen + np->opt->opt_nflen; |
| 402 | |
| 403 | inet->dport = usin->sin6_port; |
| 404 | |
| 405 | dccp_set_state(sk, DCCP_REQUESTING); |
| 406 | err = dccp_v6_hash_connect(sk); |
| 407 | if (err) |
| 408 | goto late_failure; |
| 409 | /* FIXME */ |
| 410 | #if 0 |
| 411 | dp->dccps_gar = secure_dccp_v6_sequence_number(np->saddr.s6_addr32, |
| 412 | np->daddr.s6_addr32, |
| 413 | inet->sport, |
| 414 | inet->dport); |
| 415 | #endif |
| 416 | err = dccp_connect(sk); |
| 417 | if (err) |
| 418 | goto late_failure; |
| 419 | |
| 420 | return 0; |
| 421 | |
| 422 | late_failure: |
| 423 | dccp_set_state(sk, DCCP_CLOSED); |
| 424 | __sk_dst_reset(sk); |
| 425 | failure: |
| 426 | inet->dport = 0; |
| 427 | sk->sk_route_caps = 0; |
| 428 | return err; |
| 429 | } |
| 430 | |
| 431 | static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
| 432 | int type, int code, int offset, __u32 info) |
| 433 | { |
| 434 | struct ipv6hdr *hdr = (struct ipv6hdr *)skb->data; |
| 435 | const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset); |
| 436 | struct ipv6_pinfo *np; |
| 437 | struct sock *sk; |
| 438 | int err; |
| 439 | __u64 seq; |
| 440 | |
| 441 | sk = inet6_lookup(&dccp_hashinfo, &hdr->daddr, dh->dccph_dport, |
| 442 | &hdr->saddr, dh->dccph_sport, skb->dev->ifindex); |
| 443 | |
| 444 | if (sk == NULL) { |
| 445 | ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS); |
| 446 | return; |
| 447 | } |
| 448 | |
| 449 | if (sk->sk_state == DCCP_TIME_WAIT) { |
| 450 | inet_twsk_put((struct inet_timewait_sock *)sk); |
| 451 | return; |
| 452 | } |
| 453 | |
| 454 | bh_lock_sock(sk); |
| 455 | if (sock_owned_by_user(sk)) |
| 456 | NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS); |
| 457 | |
| 458 | if (sk->sk_state == DCCP_CLOSED) |
| 459 | goto out; |
| 460 | |
| 461 | np = inet6_sk(sk); |
| 462 | |
| 463 | if (type == ICMPV6_PKT_TOOBIG) { |
| 464 | struct dccp_sock *dp = dccp_sk(sk); |
| 465 | struct dst_entry *dst = NULL; |
| 466 | |
| 467 | if (sock_owned_by_user(sk)) |
| 468 | goto out; |
| 469 | if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED)) |
| 470 | goto out; |
| 471 | |
| 472 | /* icmp should have updated the destination cache entry */ |
| 473 | dst = __sk_dst_check(sk, np->dst_cookie); |
| 474 | |
| 475 | if (dst == NULL) { |
| 476 | struct inet_sock *inet = inet_sk(sk); |
| 477 | struct flowi fl; |
| 478 | |
| 479 | /* BUGGG_FUTURE: Again, it is not clear how |
| 480 | to handle rthdr case. Ignore this complexity |
| 481 | for now. |
| 482 | */ |
| 483 | memset(&fl, 0, sizeof(fl)); |
| 484 | fl.proto = IPPROTO_DCCP; |
| 485 | ipv6_addr_copy(&fl.fl6_dst, &np->daddr); |
| 486 | ipv6_addr_copy(&fl.fl6_src, &np->saddr); |
| 487 | fl.oif = sk->sk_bound_dev_if; |
| 488 | fl.fl_ip_dport = inet->dport; |
| 489 | fl.fl_ip_sport = inet->sport; |
| 490 | |
| 491 | if ((err = ip6_dst_lookup(sk, &dst, &fl))) { |
| 492 | sk->sk_err_soft = -err; |
| 493 | goto out; |
| 494 | } |
| 495 | |
| 496 | if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) { |
| 497 | sk->sk_err_soft = -err; |
| 498 | goto out; |
| 499 | } |
| 500 | |
| 501 | } else |
| 502 | dst_hold(dst); |
| 503 | |
| 504 | if (dp->dccps_pmtu_cookie > dst_mtu(dst)) { |
| 505 | dccp_sync_mss(sk, dst_mtu(dst)); |
| 506 | } /* else let the usual retransmit timer handle it */ |
| 507 | dst_release(dst); |
| 508 | goto out; |
| 509 | } |
| 510 | |
| 511 | icmpv6_err_convert(type, code, &err); |
| 512 | |
| 513 | seq = DCCP_SKB_CB(skb)->dccpd_seq; |
| 514 | /* Might be for an request_sock */ |
| 515 | switch (sk->sk_state) { |
| 516 | struct request_sock *req, **prev; |
| 517 | case DCCP_LISTEN: |
| 518 | if (sock_owned_by_user(sk)) |
| 519 | goto out; |
| 520 | |
| 521 | req = inet6_csk_search_req(sk, &prev, dh->dccph_dport, |
| 522 | &hdr->daddr, &hdr->saddr, |
| 523 | inet6_iif(skb)); |
| 524 | if (!req) |
| 525 | goto out; |
| 526 | |
| 527 | /* ICMPs are not backlogged, hence we cannot get |
| 528 | * an established socket here. |
| 529 | */ |
| 530 | BUG_TRAP(req->sk == NULL); |
| 531 | |
| 532 | if (seq != dccp_rsk(req)->dreq_iss) { |
| 533 | NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); |
| 534 | goto out; |
| 535 | } |
| 536 | |
| 537 | inet_csk_reqsk_queue_drop(sk, req, prev); |
| 538 | goto out; |
| 539 | |
| 540 | case DCCP_REQUESTING: |
| 541 | case DCCP_RESPOND: /* Cannot happen. |
| 542 | It can, it SYNs are crossed. --ANK */ |
| 543 | if (!sock_owned_by_user(sk)) { |
| 544 | DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); |
| 545 | sk->sk_err = err; |
| 546 | /* |
| 547 | * Wake people up to see the error |
| 548 | * (see connect in sock.c) |
| 549 | */ |
| 550 | sk->sk_error_report(sk); |
| 551 | |
| 552 | dccp_done(sk); |
| 553 | } else |
| 554 | sk->sk_err_soft = err; |
| 555 | goto out; |
| 556 | } |
| 557 | |
| 558 | if (!sock_owned_by_user(sk) && np->recverr) { |
| 559 | sk->sk_err = err; |
| 560 | sk->sk_error_report(sk); |
| 561 | } else |
| 562 | sk->sk_err_soft = err; |
| 563 | |
| 564 | out: |
| 565 | bh_unlock_sock(sk); |
| 566 | sock_put(sk); |
| 567 | } |
| 568 | |
| 569 | |
| 570 | static int dccp_v6_send_response(struct sock *sk, struct request_sock *req, |
| 571 | struct dst_entry *dst) |
| 572 | { |
| 573 | struct inet6_request_sock *ireq6 = inet6_rsk(req); |
| 574 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 575 | struct sk_buff *skb; |
| 576 | struct ipv6_txoptions *opt = NULL; |
| 577 | struct in6_addr *final_p = NULL, final; |
| 578 | struct flowi fl; |
| 579 | int err = -1; |
| 580 | |
| 581 | memset(&fl, 0, sizeof(fl)); |
| 582 | fl.proto = IPPROTO_DCCP; |
| 583 | ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr); |
| 584 | ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr); |
| 585 | fl.fl6_flowlabel = 0; |
| 586 | fl.oif = ireq6->iif; |
| 587 | fl.fl_ip_dport = inet_rsk(req)->rmt_port; |
| 588 | fl.fl_ip_sport = inet_sk(sk)->sport; |
| 589 | |
| 590 | if (dst == NULL) { |
| 591 | opt = np->opt; |
| 592 | if (opt == NULL && |
| 593 | np->rxopt.bits.osrcrt == 2 && |
| 594 | ireq6->pktopts) { |
| 595 | struct sk_buff *pktopts = ireq6->pktopts; |
| 596 | struct inet6_skb_parm *rxopt = IP6CB(pktopts); |
| 597 | if (rxopt->srcrt) |
| 598 | opt = ipv6_invert_rthdr(sk, |
| 599 | (struct ipv6_rt_hdr *)(pktopts->nh.raw + |
| 600 | rxopt->srcrt)); |
| 601 | } |
| 602 | |
| 603 | if (opt && opt->srcrt) { |
| 604 | struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt; |
| 605 | ipv6_addr_copy(&final, &fl.fl6_dst); |
| 606 | ipv6_addr_copy(&fl.fl6_dst, rt0->addr); |
| 607 | final_p = &final; |
| 608 | } |
| 609 | |
| 610 | err = ip6_dst_lookup(sk, &dst, &fl); |
| 611 | if (err) |
| 612 | goto done; |
| 613 | if (final_p) |
| 614 | ipv6_addr_copy(&fl.fl6_dst, final_p); |
| 615 | if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) |
| 616 | goto done; |
| 617 | } |
| 618 | |
| 619 | skb = dccp_make_response(sk, dst, req); |
| 620 | if (skb != NULL) { |
| 621 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 622 | dh->dccph_checksum = dccp_v6_check(dh, skb->len, |
| 623 | &ireq6->loc_addr, |
| 624 | &ireq6->rmt_addr, |
| 625 | csum_partial((char *)dh, |
| 626 | skb->len, |
| 627 | skb->csum)); |
| 628 | ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr); |
| 629 | err = ip6_xmit(sk, skb, &fl, opt, 0); |
| 630 | if (err == NET_XMIT_CN) |
| 631 | err = 0; |
| 632 | } |
| 633 | |
| 634 | done: |
| 635 | if (opt && opt != np->opt) |
| 636 | sock_kfree_s(sk, opt, opt->tot_len); |
| 637 | return err; |
| 638 | } |
| 639 | |
| 640 | static void dccp_v6_reqsk_destructor(struct request_sock *req) |
| 641 | { |
| 642 | if (inet6_rsk(req)->pktopts != NULL) |
| 643 | kfree_skb(inet6_rsk(req)->pktopts); |
| 644 | } |
| 645 | |
| 646 | static struct request_sock_ops dccp6_request_sock_ops = { |
| 647 | .family = AF_INET6, |
| 648 | .obj_size = sizeof(struct dccp6_request_sock), |
| 649 | .rtx_syn_ack = dccp_v6_send_response, |
| 650 | .send_ack = dccp_v6_reqsk_send_ack, |
| 651 | .destructor = dccp_v6_reqsk_destructor, |
| 652 | .send_reset = dccp_v6_ctl_send_reset, |
| 653 | }; |
| 654 | |
| 655 | static void dccp_v6_send_check(struct sock *sk, int len, struct sk_buff *skb) |
| 656 | { |
| 657 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 658 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 659 | |
| 660 | dh->dccph_checksum = csum_ipv6_magic(&np->saddr, &np->daddr, |
| 661 | len, IPPROTO_DCCP, |
| 662 | csum_partial((char *)dh, |
| 663 | dh->dccph_doff << 2, |
| 664 | skb->csum)); |
| 665 | } |
| 666 | |
| 667 | static void dccp_v6_ctl_send_reset(struct sk_buff *rxskb) |
| 668 | { |
| 669 | struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh; |
| 670 | const int dccp_hdr_reset_len = sizeof(struct dccp_hdr) + |
| 671 | sizeof(struct dccp_hdr_ext) + |
| 672 | sizeof(struct dccp_hdr_reset); |
| 673 | struct sk_buff *skb; |
| 674 | struct flowi fl; |
| 675 | u64 seqno; |
| 676 | |
| 677 | if (rxdh->dccph_type == DCCP_PKT_RESET) |
| 678 | return; |
| 679 | |
| 680 | if (!ipv6_unicast_destination(rxskb)) |
| 681 | return; |
| 682 | |
| 683 | /* |
| 684 | * We need to grab some memory, and put together an RST, |
| 685 | * and then put it into the queue to be sent. |
| 686 | */ |
| 687 | |
| 688 | skb = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + |
| 689 | dccp_hdr_reset_len, GFP_ATOMIC); |
| 690 | if (skb == NULL) |
| 691 | return; |
| 692 | |
| 693 | skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr) + |
| 694 | dccp_hdr_reset_len); |
| 695 | |
| 696 | skb->h.raw = skb_push(skb, dccp_hdr_reset_len); |
| 697 | dh = dccp_hdr(skb); |
| 698 | memset(dh, 0, dccp_hdr_reset_len); |
| 699 | |
| 700 | /* Swap the send and the receive. */ |
| 701 | dh->dccph_type = DCCP_PKT_RESET; |
| 702 | dh->dccph_sport = rxdh->dccph_dport; |
| 703 | dh->dccph_dport = rxdh->dccph_sport; |
| 704 | dh->dccph_doff = dccp_hdr_reset_len / 4; |
| 705 | dh->dccph_x = 1; |
| 706 | dccp_hdr_reset(skb)->dccph_reset_code = |
| 707 | DCCP_SKB_CB(rxskb)->dccpd_reset_code; |
| 708 | |
| 709 | /* See "8.3.1. Abnormal Termination" in draft-ietf-dccp-spec-11 */ |
| 710 | seqno = 0; |
| 711 | if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ) |
| 712 | dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1); |
| 713 | |
| 714 | dccp_hdr_set_seq(dh, seqno); |
| 715 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), |
| 716 | DCCP_SKB_CB(rxskb)->dccpd_seq); |
| 717 | |
| 718 | memset(&fl, 0, sizeof(fl)); |
| 719 | ipv6_addr_copy(&fl.fl6_dst, &rxskb->nh.ipv6h->saddr); |
| 720 | ipv6_addr_copy(&fl.fl6_src, &rxskb->nh.ipv6h->daddr); |
| 721 | dh->dccph_checksum = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst, |
| 722 | sizeof(*dh), IPPROTO_DCCP, |
| 723 | skb->csum); |
| 724 | fl.proto = IPPROTO_DCCP; |
| 725 | fl.oif = inet6_iif(rxskb); |
| 726 | fl.fl_ip_dport = dh->dccph_dport; |
| 727 | fl.fl_ip_sport = dh->dccph_sport; |
| 728 | |
| 729 | /* sk = NULL, but it is safe for now. RST socket required. */ |
| 730 | if (!ip6_dst_lookup(NULL, &skb->dst, &fl)) { |
| 731 | if (xfrm_lookup(&skb->dst, &fl, NULL, 0) >= 0) { |
| 732 | ip6_xmit(NULL, skb, &fl, NULL, 0); |
| 733 | DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); |
| 734 | DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS); |
| 735 | return; |
| 736 | } |
| 737 | } |
| 738 | |
| 739 | kfree_skb(skb); |
| 740 | } |
| 741 | |
| 742 | static void dccp_v6_ctl_send_ack(struct sk_buff *rxskb) |
| 743 | { |
| 744 | struct flowi fl; |
| 745 | struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh; |
| 746 | const int dccp_hdr_ack_len = sizeof(struct dccp_hdr) + |
| 747 | sizeof(struct dccp_hdr_ext) + |
| 748 | sizeof(struct dccp_hdr_ack_bits); |
| 749 | struct sk_buff *skb; |
| 750 | |
| 751 | skb = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + |
| 752 | dccp_hdr_ack_len, GFP_ATOMIC); |
| 753 | if (skb == NULL) |
| 754 | return; |
| 755 | |
| 756 | skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr) + |
| 757 | dccp_hdr_ack_len); |
| 758 | |
| 759 | skb->h.raw = skb_push(skb, dccp_hdr_ack_len); |
| 760 | dh = dccp_hdr(skb); |
| 761 | memset(dh, 0, dccp_hdr_ack_len); |
| 762 | |
| 763 | /* Build DCCP header and checksum it. */ |
| 764 | dh->dccph_type = DCCP_PKT_ACK; |
| 765 | dh->dccph_sport = rxdh->dccph_dport; |
| 766 | dh->dccph_dport = rxdh->dccph_sport; |
| 767 | dh->dccph_doff = dccp_hdr_ack_len / 4; |
| 768 | dh->dccph_x = 1; |
| 769 | |
| 770 | dccp_hdr_set_seq(dh, DCCP_SKB_CB(rxskb)->dccpd_ack_seq); |
| 771 | dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), |
| 772 | DCCP_SKB_CB(rxskb)->dccpd_seq); |
| 773 | |
| 774 | memset(&fl, 0, sizeof(fl)); |
| 775 | ipv6_addr_copy(&fl.fl6_dst, &rxskb->nh.ipv6h->saddr); |
| 776 | ipv6_addr_copy(&fl.fl6_src, &rxskb->nh.ipv6h->daddr); |
| 777 | |
| 778 | /* FIXME: calculate checksum, IPv4 also should... */ |
| 779 | |
| 780 | fl.proto = IPPROTO_DCCP; |
| 781 | fl.oif = inet6_iif(rxskb); |
| 782 | fl.fl_ip_dport = dh->dccph_dport; |
| 783 | fl.fl_ip_sport = dh->dccph_sport; |
| 784 | |
| 785 | if (!ip6_dst_lookup(NULL, &skb->dst, &fl)) { |
| 786 | if (xfrm_lookup(&skb->dst, &fl, NULL, 0) >= 0) { |
| 787 | ip6_xmit(NULL, skb, &fl, NULL, 0); |
| 788 | DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS); |
| 789 | return; |
| 790 | } |
| 791 | } |
| 792 | |
| 793 | kfree_skb(skb); |
| 794 | } |
| 795 | |
| 796 | static void dccp_v6_reqsk_send_ack(struct sk_buff *skb, |
| 797 | struct request_sock *req) |
| 798 | { |
| 799 | dccp_v6_ctl_send_ack(skb); |
| 800 | } |
| 801 | |
| 802 | static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) |
| 803 | { |
| 804 | const struct dccp_hdr *dh = dccp_hdr(skb); |
| 805 | const struct ipv6hdr *iph = skb->nh.ipv6h; |
| 806 | struct sock *nsk; |
| 807 | struct request_sock **prev; |
| 808 | /* Find possible connection requests. */ |
| 809 | struct request_sock *req = inet6_csk_search_req(sk, &prev, |
| 810 | dh->dccph_sport, |
| 811 | &iph->saddr, |
| 812 | &iph->daddr, |
| 813 | inet6_iif(skb)); |
| 814 | if (req != NULL) |
| 815 | return dccp_check_req(sk, skb, req, prev); |
| 816 | |
| 817 | nsk = __inet6_lookup_established(&dccp_hashinfo, |
| 818 | &iph->saddr, dh->dccph_sport, |
| 819 | &iph->daddr, ntohs(dh->dccph_dport), |
| 820 | inet6_iif(skb)); |
| 821 | |
| 822 | if (nsk != NULL) { |
| 823 | if (nsk->sk_state != DCCP_TIME_WAIT) { |
| 824 | bh_lock_sock(nsk); |
| 825 | return nsk; |
| 826 | } |
| 827 | inet_twsk_put((struct inet_timewait_sock *)nsk); |
| 828 | return NULL; |
| 829 | } |
| 830 | |
| 831 | return sk; |
| 832 | } |
| 833 | |
| 834 | static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb) |
| 835 | { |
| 836 | struct inet_request_sock *ireq; |
| 837 | struct dccp_sock dp; |
| 838 | struct request_sock *req; |
| 839 | struct dccp_request_sock *dreq; |
| 840 | struct inet6_request_sock *ireq6; |
| 841 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 842 | const __u32 service = dccp_hdr_request(skb)->dccph_req_service; |
| 843 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
| 844 | __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY; |
| 845 | |
| 846 | if (skb->protocol == htons(ETH_P_IP)) |
| 847 | return dccp_v4_conn_request(sk, skb); |
| 848 | |
| 849 | if (!ipv6_unicast_destination(skb)) |
| 850 | goto drop; |
| 851 | |
| 852 | if (dccp_bad_service_code(sk, service)) { |
| 853 | reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; |
| 854 | goto drop; |
| 855 | } |
| 856 | /* |
| 857 | * There are no SYN attacks on IPv6, yet... |
| 858 | */ |
| 859 | if (inet_csk_reqsk_queue_is_full(sk)) |
| 860 | goto drop; |
| 861 | |
| 862 | if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) |
| 863 | goto drop; |
| 864 | |
| 865 | req = inet6_reqsk_alloc(sk->sk_prot->rsk_prot); |
| 866 | if (req == NULL) |
| 867 | goto drop; |
| 868 | |
| 869 | /* FIXME: process options */ |
| 870 | |
| 871 | dccp_openreq_init(req, &dp, skb); |
| 872 | |
| 873 | ireq6 = inet6_rsk(req); |
| 874 | ireq = inet_rsk(req); |
| 875 | ipv6_addr_copy(&ireq6->rmt_addr, &skb->nh.ipv6h->saddr); |
| 876 | ipv6_addr_copy(&ireq6->loc_addr, &skb->nh.ipv6h->daddr); |
| 877 | req->rcv_wnd = 100; /* Fake, option parsing will get the |
| 878 | right value */ |
| 879 | ireq6->pktopts = NULL; |
| 880 | |
| 881 | if (ipv6_opt_accepted(sk, skb) || |
| 882 | np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo || |
| 883 | np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) { |
| 884 | atomic_inc(&skb->users); |
| 885 | ireq6->pktopts = skb; |
| 886 | } |
| 887 | ireq6->iif = sk->sk_bound_dev_if; |
| 888 | |
| 889 | /* So that link locals have meaning */ |
| 890 | if (!sk->sk_bound_dev_if && |
| 891 | ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL) |
| 892 | ireq6->iif = inet6_iif(skb); |
| 893 | |
| 894 | /* |
| 895 | * Step 3: Process LISTEN state |
| 896 | * |
| 897 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie |
| 898 | * |
| 899 | * In fact we defer setting S.GSR, S.SWL, S.SWH to |
| 900 | * dccp_create_openreq_child. |
| 901 | */ |
| 902 | dreq = dccp_rsk(req); |
| 903 | dreq->dreq_isr = dcb->dccpd_seq; |
| 904 | dreq->dreq_iss = dccp_v6_init_sequence(sk, skb); |
| 905 | dreq->dreq_service = service; |
| 906 | |
| 907 | if (dccp_v6_send_response(sk, req, NULL)) |
| 908 | goto drop_and_free; |
| 909 | |
| 910 | inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT); |
| 911 | return 0; |
| 912 | |
| 913 | drop_and_free: |
| 914 | reqsk_free(req); |
| 915 | drop: |
| 916 | DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS); |
| 917 | dcb->dccpd_reset_code = reset_code; |
| 918 | return -1; |
| 919 | } |
| 920 | |
| 921 | static struct sock *dccp_v6_request_recv_sock(struct sock *sk, |
| 922 | struct sk_buff *skb, |
| 923 | struct request_sock *req, |
| 924 | struct dst_entry *dst) |
| 925 | { |
| 926 | struct inet6_request_sock *ireq6 = inet6_rsk(req); |
| 927 | struct ipv6_pinfo *newnp, *np = inet6_sk(sk); |
| 928 | struct inet_sock *newinet; |
| 929 | struct dccp_sock *newdp; |
| 930 | struct dccp6_sock *newdp6; |
| 931 | struct sock *newsk; |
| 932 | struct ipv6_txoptions *opt; |
| 933 | |
| 934 | if (skb->protocol == htons(ETH_P_IP)) { |
| 935 | /* |
| 936 | * v6 mapped |
| 937 | */ |
| 938 | |
| 939 | newsk = dccp_v4_request_recv_sock(sk, skb, req, dst); |
| 940 | if (newsk == NULL) |
| 941 | return NULL; |
| 942 | |
| 943 | newdp6 = (struct dccp6_sock *)newsk; |
| 944 | newdp = dccp_sk(newsk); |
| 945 | newinet = inet_sk(newsk); |
| 946 | newinet->pinet6 = &newdp6->inet6; |
| 947 | newnp = inet6_sk(newsk); |
| 948 | |
| 949 | memcpy(newnp, np, sizeof(struct ipv6_pinfo)); |
| 950 | |
| 951 | ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF), |
| 952 | newinet->daddr); |
| 953 | |
| 954 | ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF), |
| 955 | newinet->saddr); |
| 956 | |
| 957 | ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr); |
| 958 | |
| 959 | inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped; |
| 960 | newsk->sk_backlog_rcv = dccp_v4_do_rcv; |
| 961 | newnp->pktoptions = NULL; |
| 962 | newnp->opt = NULL; |
| 963 | newnp->mcast_oif = inet6_iif(skb); |
| 964 | newnp->mcast_hops = skb->nh.ipv6h->hop_limit; |
| 965 | |
| 966 | /* |
| 967 | * No need to charge this sock to the relevant IPv6 refcnt debug socks count |
| 968 | * here, dccp_create_openreq_child now does this for us, see the comment in |
| 969 | * that function for the gory details. -acme |
| 970 | */ |
| 971 | |
| 972 | /* It is tricky place. Until this moment IPv4 tcp |
| 973 | worked with IPv6 icsk.icsk_af_ops. |
| 974 | Sync it now. |
| 975 | */ |
| 976 | dccp_sync_mss(newsk, newdp->dccps_pmtu_cookie); |
| 977 | |
| 978 | return newsk; |
| 979 | } |
| 980 | |
| 981 | opt = np->opt; |
| 982 | |
| 983 | if (sk_acceptq_is_full(sk)) |
| 984 | goto out_overflow; |
| 985 | |
| 986 | if (np->rxopt.bits.osrcrt == 2 && |
| 987 | opt == NULL && ireq6->pktopts) { |
| 988 | struct inet6_skb_parm *rxopt = IP6CB(ireq6->pktopts); |
| 989 | if (rxopt->srcrt) |
| 990 | opt = ipv6_invert_rthdr(sk, |
| 991 | (struct ipv6_rt_hdr *)(ireq6->pktopts->nh.raw + |
| 992 | rxopt->srcrt)); |
| 993 | } |
| 994 | |
| 995 | if (dst == NULL) { |
| 996 | struct in6_addr *final_p = NULL, final; |
| 997 | struct flowi fl; |
| 998 | |
| 999 | memset(&fl, 0, sizeof(fl)); |
| 1000 | fl.proto = IPPROTO_DCCP; |
| 1001 | ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr); |
| 1002 | if (opt && opt->srcrt) { |
| 1003 | struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; |
| 1004 | ipv6_addr_copy(&final, &fl.fl6_dst); |
| 1005 | ipv6_addr_copy(&fl.fl6_dst, rt0->addr); |
| 1006 | final_p = &final; |
| 1007 | } |
| 1008 | ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr); |
| 1009 | fl.oif = sk->sk_bound_dev_if; |
| 1010 | fl.fl_ip_dport = inet_rsk(req)->rmt_port; |
| 1011 | fl.fl_ip_sport = inet_sk(sk)->sport; |
| 1012 | |
| 1013 | if (ip6_dst_lookup(sk, &dst, &fl)) |
| 1014 | goto out; |
| 1015 | |
| 1016 | if (final_p) |
| 1017 | ipv6_addr_copy(&fl.fl6_dst, final_p); |
| 1018 | |
| 1019 | if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0) |
| 1020 | goto out; |
| 1021 | } |
| 1022 | |
| 1023 | newsk = dccp_create_openreq_child(sk, req, skb); |
| 1024 | if (newsk == NULL) |
| 1025 | goto out; |
| 1026 | |
| 1027 | /* |
| 1028 | * No need to charge this sock to the relevant IPv6 refcnt debug socks |
| 1029 | * count here, dccp_create_openreq_child now does this for us, see the |
| 1030 | * comment in that function for the gory details. -acme |
| 1031 | */ |
| 1032 | |
| 1033 | ip6_dst_store(newsk, dst, NULL); |
| 1034 | newsk->sk_route_caps = dst->dev->features & |
| 1035 | ~(NETIF_F_IP_CSUM | NETIF_F_TSO); |
| 1036 | |
| 1037 | newdp6 = (struct dccp6_sock *)newsk; |
| 1038 | newinet = inet_sk(newsk); |
| 1039 | newinet->pinet6 = &newdp6->inet6; |
| 1040 | newdp = dccp_sk(newsk); |
| 1041 | newnp = inet6_sk(newsk); |
| 1042 | |
| 1043 | memcpy(newnp, np, sizeof(struct ipv6_pinfo)); |
| 1044 | |
| 1045 | ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr); |
| 1046 | ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr); |
| 1047 | ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr); |
| 1048 | newsk->sk_bound_dev_if = ireq6->iif; |
| 1049 | |
| 1050 | /* Now IPv6 options... |
| 1051 | |
| 1052 | First: no IPv4 options. |
| 1053 | */ |
| 1054 | newinet->opt = NULL; |
| 1055 | |
| 1056 | /* Clone RX bits */ |
| 1057 | newnp->rxopt.all = np->rxopt.all; |
| 1058 | |
| 1059 | /* Clone pktoptions received with SYN */ |
| 1060 | newnp->pktoptions = NULL; |
| 1061 | if (ireq6->pktopts != NULL) { |
| 1062 | newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC); |
| 1063 | kfree_skb(ireq6->pktopts); |
| 1064 | ireq6->pktopts = NULL; |
| 1065 | if (newnp->pktoptions) |
| 1066 | skb_set_owner_r(newnp->pktoptions, newsk); |
| 1067 | } |
| 1068 | newnp->opt = NULL; |
| 1069 | newnp->mcast_oif = inet6_iif(skb); |
| 1070 | newnp->mcast_hops = skb->nh.ipv6h->hop_limit; |
| 1071 | |
| 1072 | /* Clone native IPv6 options from listening socket (if any) |
| 1073 | |
| 1074 | Yes, keeping reference count would be much more clever, |
| 1075 | but we make one more one thing there: reattach optmem |
| 1076 | to newsk. |
| 1077 | */ |
| 1078 | if (opt) { |
| 1079 | newnp->opt = ipv6_dup_options(newsk, opt); |
| 1080 | if (opt != np->opt) |
| 1081 | sock_kfree_s(sk, opt, opt->tot_len); |
| 1082 | } |
| 1083 | |
| 1084 | newdp->dccps_ext_header_len = 0; |
| 1085 | if (newnp->opt) |
| 1086 | newdp->dccps_ext_header_len = newnp->opt->opt_nflen + |
| 1087 | newnp->opt->opt_flen; |
| 1088 | |
| 1089 | dccp_sync_mss(newsk, dst_mtu(dst)); |
| 1090 | |
| 1091 | newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6; |
| 1092 | |
| 1093 | __inet6_hash(&dccp_hashinfo, newsk); |
| 1094 | inet_inherit_port(&dccp_hashinfo, sk, newsk); |
| 1095 | |
| 1096 | return newsk; |
| 1097 | |
| 1098 | out_overflow: |
| 1099 | NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS); |
| 1100 | out: |
| 1101 | NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS); |
| 1102 | if (opt && opt != np->opt) |
| 1103 | sock_kfree_s(sk, opt, opt->tot_len); |
| 1104 | dst_release(dst); |
| 1105 | return NULL; |
| 1106 | } |
| 1107 | |
| 1108 | /* The socket must have it's spinlock held when we get |
| 1109 | * here. |
| 1110 | * |
| 1111 | * We have a potential double-lock case here, so even when |
| 1112 | * doing backlog processing we use the BH locking scheme. |
| 1113 | * This is because we cannot sleep with the original spinlock |
| 1114 | * held. |
| 1115 | */ |
| 1116 | static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) |
| 1117 | { |
| 1118 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 1119 | struct sk_buff *opt_skb = NULL; |
| 1120 | |
| 1121 | /* Imagine: socket is IPv6. IPv4 packet arrives, |
| 1122 | goes to IPv4 receive handler and backlogged. |
| 1123 | From backlog it always goes here. Kerboom... |
| 1124 | Fortunately, dccp_rcv_established and rcv_established |
| 1125 | handle them correctly, but it is not case with |
| 1126 | dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK |
| 1127 | */ |
| 1128 | |
| 1129 | if (skb->protocol == htons(ETH_P_IP)) |
| 1130 | return dccp_v4_do_rcv(sk, skb); |
| 1131 | |
| 1132 | if (sk_filter(sk, skb, 0)) |
| 1133 | goto discard; |
| 1134 | |
| 1135 | /* |
| 1136 | * socket locking is here for SMP purposes as backlog rcv |
| 1137 | * is currently called with bh processing disabled. |
| 1138 | */ |
| 1139 | |
| 1140 | /* Do Stevens' IPV6_PKTOPTIONS. |
| 1141 | |
| 1142 | Yes, guys, it is the only place in our code, where we |
| 1143 | may make it not affecting IPv4. |
| 1144 | The rest of code is protocol independent, |
| 1145 | and I do not like idea to uglify IPv4. |
| 1146 | |
| 1147 | Actually, all the idea behind IPV6_PKTOPTIONS |
| 1148 | looks not very well thought. For now we latch |
| 1149 | options, received in the last packet, enqueued |
| 1150 | by tcp. Feel free to propose better solution. |
| 1151 | --ANK (980728) |
| 1152 | */ |
| 1153 | if (np->rxopt.all) |
| 1154 | opt_skb = skb_clone(skb, GFP_ATOMIC); |
| 1155 | |
| 1156 | if (sk->sk_state == DCCP_OPEN) { /* Fast path */ |
| 1157 | if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len)) |
| 1158 | goto reset; |
| 1159 | return 0; |
| 1160 | } |
| 1161 | |
| 1162 | if (sk->sk_state == DCCP_LISTEN) { |
| 1163 | struct sock *nsk = dccp_v6_hnd_req(sk, skb); |
| 1164 | if (!nsk) |
| 1165 | goto discard; |
| 1166 | |
| 1167 | /* |
| 1168 | * Queue it on the new socket if the new socket is active, |
| 1169 | * otherwise we just shortcircuit this and continue with |
| 1170 | * the new socket.. |
| 1171 | */ |
| 1172 | if(nsk != sk) { |
| 1173 | if (dccp_child_process(sk, nsk, skb)) |
| 1174 | goto reset; |
| 1175 | if (opt_skb) |
| 1176 | __kfree_skb(opt_skb); |
| 1177 | return 0; |
| 1178 | } |
| 1179 | } |
| 1180 | |
| 1181 | if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len)) |
| 1182 | goto reset; |
| 1183 | return 0; |
| 1184 | |
| 1185 | reset: |
| 1186 | dccp_v6_ctl_send_reset(skb); |
| 1187 | discard: |
| 1188 | if (opt_skb) |
| 1189 | __kfree_skb(opt_skb); |
| 1190 | kfree_skb(skb); |
| 1191 | return 0; |
| 1192 | } |
| 1193 | |
| 1194 | static int dccp_v6_rcv(struct sk_buff **pskb, unsigned int *nhoffp) |
| 1195 | { |
| 1196 | const struct dccp_hdr *dh; |
| 1197 | struct sk_buff *skb = *pskb; |
| 1198 | struct sock *sk; |
| 1199 | int rc; |
| 1200 | |
| 1201 | /* Step 1: Check header basics: */ |
| 1202 | |
| 1203 | if (dccp_invalid_packet(skb)) |
| 1204 | goto discard_it; |
| 1205 | |
| 1206 | dh = dccp_hdr(skb); |
| 1207 | |
| 1208 | DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb); |
| 1209 | DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type; |
| 1210 | |
| 1211 | if (dccp_packet_without_ack(skb)) |
| 1212 | DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ; |
| 1213 | else |
| 1214 | DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb); |
| 1215 | |
| 1216 | /* Step 2: |
| 1217 | * Look up flow ID in table and get corresponding socket */ |
| 1218 | sk = __inet6_lookup(&dccp_hashinfo, &skb->nh.ipv6h->saddr, |
| 1219 | dh->dccph_sport, |
| 1220 | &skb->nh.ipv6h->daddr, ntohs(dh->dccph_dport), |
| 1221 | inet6_iif(skb)); |
| 1222 | /* |
| 1223 | * Step 2: |
| 1224 | * If no socket ... |
| 1225 | * Generate Reset(No Connection) unless P.type == Reset |
| 1226 | * Drop packet and return |
| 1227 | */ |
| 1228 | if (sk == NULL) |
| 1229 | goto no_dccp_socket; |
| 1230 | |
| 1231 | /* |
| 1232 | * Step 2: |
| 1233 | * ... or S.state == TIMEWAIT, |
| 1234 | * Generate Reset(No Connection) unless P.type == Reset |
| 1235 | * Drop packet and return |
| 1236 | */ |
| 1237 | |
| 1238 | if (sk->sk_state == DCCP_TIME_WAIT) |
| 1239 | goto do_time_wait; |
| 1240 | |
| 1241 | if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) |
| 1242 | goto discard_and_relse; |
| 1243 | |
| 1244 | if (sk_filter(sk, skb, 0)) |
| 1245 | goto discard_and_relse; |
| 1246 | |
| 1247 | skb->dev = NULL; |
| 1248 | |
| 1249 | bh_lock_sock(sk); |
| 1250 | rc = 0; |
| 1251 | if (!sock_owned_by_user(sk)) |
| 1252 | rc = dccp_v6_do_rcv(sk, skb); |
| 1253 | else |
| 1254 | sk_add_backlog(sk, skb); |
| 1255 | bh_unlock_sock(sk); |
| 1256 | |
| 1257 | sock_put(sk); |
| 1258 | return rc ? -1 : 0; |
| 1259 | |
| 1260 | no_dccp_socket: |
| 1261 | if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) |
| 1262 | goto discard_it; |
| 1263 | /* |
| 1264 | * Step 2: |
| 1265 | * Generate Reset(No Connection) unless P.type == Reset |
| 1266 | * Drop packet and return |
| 1267 | */ |
| 1268 | if (dh->dccph_type != DCCP_PKT_RESET) { |
| 1269 | DCCP_SKB_CB(skb)->dccpd_reset_code = |
| 1270 | DCCP_RESET_CODE_NO_CONNECTION; |
| 1271 | dccp_v6_ctl_send_reset(skb); |
| 1272 | } |
| 1273 | discard_it: |
| 1274 | |
| 1275 | /* |
| 1276 | * Discard frame |
| 1277 | */ |
| 1278 | |
| 1279 | kfree_skb(skb); |
| 1280 | return 0; |
| 1281 | |
| 1282 | discard_and_relse: |
| 1283 | sock_put(sk); |
| 1284 | goto discard_it; |
| 1285 | |
| 1286 | do_time_wait: |
| 1287 | inet_twsk_put((struct inet_timewait_sock *)sk); |
| 1288 | goto no_dccp_socket; |
| 1289 | } |
| 1290 | |
| 1291 | static struct inet_connection_sock_af_ops dccp_ipv6_af_ops = { |
| 1292 | .queue_xmit = inet6_csk_xmit, |
| 1293 | .send_check = dccp_v6_send_check, |
| 1294 | .rebuild_header = inet6_sk_rebuild_header, |
| 1295 | .conn_request = dccp_v6_conn_request, |
| 1296 | .syn_recv_sock = dccp_v6_request_recv_sock, |
| 1297 | .net_header_len = sizeof(struct ipv6hdr), |
| 1298 | .setsockopt = ipv6_setsockopt, |
| 1299 | .getsockopt = ipv6_getsockopt, |
| 1300 | .addr2sockaddr = inet6_csk_addr2sockaddr, |
| 1301 | .sockaddr_len = sizeof(struct sockaddr_in6) |
| 1302 | }; |
| 1303 | |
| 1304 | /* |
| 1305 | * DCCP over IPv4 via INET6 API |
| 1306 | */ |
| 1307 | static struct inet_connection_sock_af_ops dccp_ipv6_mapped = { |
| 1308 | .queue_xmit = ip_queue_xmit, |
| 1309 | .send_check = dccp_v4_send_check, |
| 1310 | .rebuild_header = inet_sk_rebuild_header, |
| 1311 | .conn_request = dccp_v6_conn_request, |
| 1312 | .syn_recv_sock = dccp_v6_request_recv_sock, |
| 1313 | .net_header_len = sizeof(struct iphdr), |
| 1314 | .setsockopt = ipv6_setsockopt, |
| 1315 | .getsockopt = ipv6_getsockopt, |
| 1316 | .addr2sockaddr = inet6_csk_addr2sockaddr, |
| 1317 | .sockaddr_len = sizeof(struct sockaddr_in6) |
| 1318 | }; |
| 1319 | |
| 1320 | /* NOTE: A lot of things set to zero explicitly by call to |
| 1321 | * sk_alloc() so need not be done here. |
| 1322 | */ |
| 1323 | static int dccp_v6_init_sock(struct sock *sk) |
| 1324 | { |
| 1325 | int err = dccp_v4_init_sock(sk); |
| 1326 | |
| 1327 | if (err == 0) |
| 1328 | inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops; |
| 1329 | |
| 1330 | return err; |
| 1331 | } |
| 1332 | |
| 1333 | static int dccp_v6_destroy_sock(struct sock *sk) |
| 1334 | { |
| 1335 | dccp_v4_destroy_sock(sk); |
| 1336 | return inet6_destroy_sock(sk); |
| 1337 | } |
| 1338 | |
| 1339 | static struct proto dccp_v6_prot = { |
| 1340 | .name = "DCCPv6", |
| 1341 | .owner = THIS_MODULE, |
| 1342 | .close = dccp_close, |
| 1343 | .connect = dccp_v6_connect, |
| 1344 | .disconnect = dccp_disconnect, |
| 1345 | .ioctl = dccp_ioctl, |
| 1346 | .init = dccp_v6_init_sock, |
| 1347 | .setsockopt = dccp_setsockopt, |
| 1348 | .getsockopt = dccp_getsockopt, |
| 1349 | .sendmsg = dccp_sendmsg, |
| 1350 | .recvmsg = dccp_recvmsg, |
| 1351 | .backlog_rcv = dccp_v6_do_rcv, |
| 1352 | .hash = dccp_v6_hash, |
| 1353 | .unhash = dccp_unhash, |
| 1354 | .accept = inet_csk_accept, |
| 1355 | .get_port = dccp_v6_get_port, |
| 1356 | .shutdown = dccp_shutdown, |
| 1357 | .destroy = dccp_v6_destroy_sock, |
| 1358 | .orphan_count = &dccp_orphan_count, |
| 1359 | .max_header = MAX_DCCP_HEADER, |
| 1360 | .obj_size = sizeof(struct dccp6_sock), |
| 1361 | .rsk_prot = &dccp6_request_sock_ops, |
| 1362 | .twsk_obj_size = sizeof(struct dccp6_timewait_sock), |
| 1363 | }; |
| 1364 | |
| 1365 | static struct inet6_protocol dccp_v6_protocol = { |
| 1366 | .handler = dccp_v6_rcv, |
| 1367 | .err_handler = dccp_v6_err, |
| 1368 | .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, |
| 1369 | }; |
| 1370 | |
| 1371 | static struct proto_ops inet6_dccp_ops = { |
| 1372 | .family = PF_INET6, |
| 1373 | .owner = THIS_MODULE, |
| 1374 | .release = inet6_release, |
| 1375 | .bind = inet6_bind, |
| 1376 | .connect = inet_stream_connect, |
| 1377 | .socketpair = sock_no_socketpair, |
| 1378 | .accept = inet_accept, |
| 1379 | .getname = inet6_getname, |
| 1380 | .poll = dccp_poll, |
| 1381 | .ioctl = inet6_ioctl, |
| 1382 | .listen = inet_dccp_listen, |
| 1383 | .shutdown = inet_shutdown, |
| 1384 | .setsockopt = sock_common_setsockopt, |
| 1385 | .getsockopt = sock_common_getsockopt, |
| 1386 | .sendmsg = inet_sendmsg, |
| 1387 | .recvmsg = sock_common_recvmsg, |
| 1388 | .mmap = sock_no_mmap, |
| 1389 | .sendpage = sock_no_sendpage, |
| 1390 | }; |
| 1391 | |
| 1392 | static struct inet_protosw dccp_v6_protosw = { |
| 1393 | .type = SOCK_DCCP, |
| 1394 | .protocol = IPPROTO_DCCP, |
| 1395 | .prot = &dccp_v6_prot, |
| 1396 | .ops = &inet6_dccp_ops, |
| 1397 | .capability = -1, |
| 1398 | }; |
| 1399 | |
| 1400 | static int __init dccp_v6_init(void) |
| 1401 | { |
| 1402 | int err = proto_register(&dccp_v6_prot, 1); |
| 1403 | |
| 1404 | if (err != 0) |
| 1405 | goto out; |
| 1406 | |
| 1407 | err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP); |
| 1408 | if (err != 0) |
| 1409 | goto out_unregister_proto; |
| 1410 | |
| 1411 | inet6_register_protosw(&dccp_v6_protosw); |
| 1412 | out: |
| 1413 | return err; |
| 1414 | out_unregister_proto: |
| 1415 | proto_unregister(&dccp_v6_prot); |
| 1416 | goto out; |
| 1417 | } |
| 1418 | |
| 1419 | static void __exit dccp_v6_exit(void) |
| 1420 | { |
| 1421 | inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP); |
| 1422 | inet6_unregister_protosw(&dccp_v6_protosw); |
| 1423 | proto_unregister(&dccp_v6_prot); |
| 1424 | } |
| 1425 | |
| 1426 | module_init(dccp_v6_init); |
| 1427 | module_exit(dccp_v6_exit); |
| 1428 | |
| 1429 | /* |
| 1430 | * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33) |
| 1431 | * values directly, Also cover the case where the protocol is not specified, |
| 1432 | * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP |
| 1433 | */ |
| 1434 | MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-33-type-6"); |
| 1435 | MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-0-type-6"); |
| 1436 | MODULE_LICENSE("GPL"); |
| 1437 | MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>"); |
| 1438 | MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol"); |