| 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
| 2 | /* |
| 3 | * net/dccp/ipv4.c |
| 4 | * |
| 5 | * An implementation of the DCCP protocol |
| 6 | * Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| 7 | */ |
| 8 | |
| 9 | #include <linux/dccp.h> |
| 10 | #include <linux/icmp.h> |
| 11 | #include <linux/slab.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/skbuff.h> |
| 14 | #include <linux/random.h> |
| 15 | |
| 16 | #include <net/icmp.h> |
| 17 | #include <net/inet_common.h> |
| 18 | #include <net/inet_hashtables.h> |
| 19 | #include <net/inet_sock.h> |
| 20 | #include <net/protocol.h> |
| 21 | #include <net/sock.h> |
| 22 | #include <net/timewait_sock.h> |
| 23 | #include <net/tcp_states.h> |
| 24 | #include <net/xfrm.h> |
| 25 | #include <net/secure_seq.h> |
| 26 | #include <net/netns/generic.h> |
| 27 | #include <net/rstreason.h> |
| 28 | |
| 29 | #include "ackvec.h" |
| 30 | #include "ccid.h" |
| 31 | #include "dccp.h" |
| 32 | #include "feat.h" |
| 33 | |
| 34 | struct dccp_v4_pernet { |
| 35 | struct sock *v4_ctl_sk; |
| 36 | }; |
| 37 | |
| 38 | static unsigned int dccp_v4_pernet_id __read_mostly; |
| 39 | |
| 40 | /* |
| 41 | * The per-net v4_ctl_sk socket is used for responding to |
| 42 | * the Out-of-the-blue (OOTB) packets. A control sock will be created |
| 43 | * for this socket at the initialization time. |
| 44 | */ |
| 45 | |
| 46 | int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) |
| 47 | { |
| 48 | const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr; |
| 49 | struct inet_sock *inet = inet_sk(sk); |
| 50 | struct dccp_sock *dp = dccp_sk(sk); |
| 51 | __be16 orig_sport, orig_dport; |
| 52 | __be32 daddr, nexthop; |
| 53 | struct flowi4 *fl4; |
| 54 | struct rtable *rt; |
| 55 | int err; |
| 56 | struct ip_options_rcu *inet_opt; |
| 57 | |
| 58 | dp->dccps_role = DCCP_ROLE_CLIENT; |
| 59 | |
| 60 | if (addr_len < sizeof(struct sockaddr_in)) |
| 61 | return -EINVAL; |
| 62 | |
| 63 | if (usin->sin_family != AF_INET) |
| 64 | return -EAFNOSUPPORT; |
| 65 | |
| 66 | nexthop = daddr = usin->sin_addr.s_addr; |
| 67 | |
| 68 | inet_opt = rcu_dereference_protected(inet->inet_opt, |
| 69 | lockdep_sock_is_held(sk)); |
| 70 | if (inet_opt != NULL && inet_opt->opt.srr) { |
| 71 | if (daddr == 0) |
| 72 | return -EINVAL; |
| 73 | nexthop = inet_opt->opt.faddr; |
| 74 | } |
| 75 | |
| 76 | orig_sport = inet->inet_sport; |
| 77 | orig_dport = usin->sin_port; |
| 78 | fl4 = &inet->cork.fl.u.ip4; |
| 79 | rt = ip_route_connect(fl4, nexthop, inet->inet_saddr, |
| 80 | sk->sk_bound_dev_if, IPPROTO_DCCP, orig_sport, |
| 81 | orig_dport, sk); |
| 82 | if (IS_ERR(rt)) |
| 83 | return PTR_ERR(rt); |
| 84 | |
| 85 | if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) { |
| 86 | ip_rt_put(rt); |
| 87 | return -ENETUNREACH; |
| 88 | } |
| 89 | |
| 90 | if (inet_opt == NULL || !inet_opt->opt.srr) |
| 91 | daddr = fl4->daddr; |
| 92 | |
| 93 | if (inet->inet_saddr == 0) { |
| 94 | err = inet_bhash2_update_saddr(sk, &fl4->saddr, AF_INET); |
| 95 | if (err) { |
| 96 | ip_rt_put(rt); |
| 97 | return err; |
| 98 | } |
| 99 | } else { |
| 100 | sk_rcv_saddr_set(sk, inet->inet_saddr); |
| 101 | } |
| 102 | |
| 103 | inet->inet_dport = usin->sin_port; |
| 104 | sk_daddr_set(sk, daddr); |
| 105 | |
| 106 | inet_csk(sk)->icsk_ext_hdr_len = 0; |
| 107 | if (inet_opt) |
| 108 | inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen; |
| 109 | /* |
| 110 | * Socket identity is still unknown (sport may be zero). |
| 111 | * However we set state to DCCP_REQUESTING and not releasing socket |
| 112 | * lock select source port, enter ourselves into the hash tables and |
| 113 | * complete initialization after this. |
| 114 | */ |
| 115 | dccp_set_state(sk, DCCP_REQUESTING); |
| 116 | err = inet_hash_connect(&dccp_death_row, sk); |
| 117 | if (err != 0) |
| 118 | goto failure; |
| 119 | |
| 120 | rt = ip_route_newports(fl4, rt, orig_sport, orig_dport, |
| 121 | inet->inet_sport, inet->inet_dport, sk); |
| 122 | if (IS_ERR(rt)) { |
| 123 | err = PTR_ERR(rt); |
| 124 | rt = NULL; |
| 125 | goto failure; |
| 126 | } |
| 127 | /* OK, now commit destination to socket. */ |
| 128 | sk_setup_caps(sk, &rt->dst); |
| 129 | |
| 130 | dp->dccps_iss = secure_dccp_sequence_number(inet->inet_saddr, |
| 131 | inet->inet_daddr, |
| 132 | inet->inet_sport, |
| 133 | inet->inet_dport); |
| 134 | atomic_set(&inet->inet_id, get_random_u16()); |
| 135 | |
| 136 | err = dccp_connect(sk); |
| 137 | rt = NULL; |
| 138 | if (err != 0) |
| 139 | goto failure; |
| 140 | out: |
| 141 | return err; |
| 142 | failure: |
| 143 | /* |
| 144 | * This unhashes the socket and releases the local port, if necessary. |
| 145 | */ |
| 146 | dccp_set_state(sk, DCCP_CLOSED); |
| 147 | inet_bhash2_reset_saddr(sk); |
| 148 | ip_rt_put(rt); |
| 149 | sk->sk_route_caps = 0; |
| 150 | inet->inet_dport = 0; |
| 151 | goto out; |
| 152 | } |
| 153 | EXPORT_SYMBOL_GPL(dccp_v4_connect); |
| 154 | |
| 155 | /* |
| 156 | * This routine does path mtu discovery as defined in RFC1191. |
| 157 | */ |
| 158 | static inline void dccp_do_pmtu_discovery(struct sock *sk, |
| 159 | const struct iphdr *iph, |
| 160 | u32 mtu) |
| 161 | { |
| 162 | struct dst_entry *dst; |
| 163 | const struct inet_sock *inet = inet_sk(sk); |
| 164 | const struct dccp_sock *dp = dccp_sk(sk); |
| 165 | |
| 166 | /* We are not interested in DCCP_LISTEN and request_socks (RESPONSEs |
| 167 | * send out by Linux are always < 576bytes so they should go through |
| 168 | * unfragmented). |
| 169 | */ |
| 170 | if (sk->sk_state == DCCP_LISTEN) |
| 171 | return; |
| 172 | |
| 173 | dst = inet_csk_update_pmtu(sk, mtu); |
| 174 | if (!dst) |
| 175 | return; |
| 176 | |
| 177 | /* Something is about to be wrong... Remember soft error |
| 178 | * for the case, if this connection will not able to recover. |
| 179 | */ |
| 180 | if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst)) |
| 181 | WRITE_ONCE(sk->sk_err_soft, EMSGSIZE); |
| 182 | |
| 183 | mtu = dst_mtu(dst); |
| 184 | |
| 185 | if (inet->pmtudisc != IP_PMTUDISC_DONT && |
| 186 | ip_sk_accept_pmtu(sk) && |
| 187 | inet_csk(sk)->icsk_pmtu_cookie > mtu) { |
| 188 | dccp_sync_mss(sk, mtu); |
| 189 | |
| 190 | /* |
| 191 | * From RFC 4340, sec. 14.1: |
| 192 | * |
| 193 | * DCCP-Sync packets are the best choice for upward |
| 194 | * probing, since DCCP-Sync probes do not risk application |
| 195 | * data loss. |
| 196 | */ |
| 197 | dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC); |
| 198 | } /* else let the usual retransmit timer handle it */ |
| 199 | } |
| 200 | |
| 201 | static void dccp_do_redirect(struct sk_buff *skb, struct sock *sk) |
| 202 | { |
| 203 | struct dst_entry *dst = __sk_dst_check(sk, 0); |
| 204 | |
| 205 | if (dst) |
| 206 | dst->ops->redirect(dst, sk, skb); |
| 207 | } |
| 208 | |
| 209 | void dccp_req_err(struct sock *sk, u64 seq) |
| 210 | { |
| 211 | struct request_sock *req = inet_reqsk(sk); |
| 212 | struct net *net = sock_net(sk); |
| 213 | |
| 214 | /* |
| 215 | * ICMPs are not backlogged, hence we cannot get an established |
| 216 | * socket here. |
| 217 | */ |
| 218 | if (!between48(seq, dccp_rsk(req)->dreq_iss, dccp_rsk(req)->dreq_gss)) { |
| 219 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
| 220 | } else { |
| 221 | /* |
| 222 | * Still in RESPOND, just remove it silently. |
| 223 | * There is no good way to pass the error to the newly |
| 224 | * created socket, and POSIX does not want network |
| 225 | * errors returned from accept(). |
| 226 | */ |
| 227 | inet_csk_reqsk_queue_drop(req->rsk_listener, req); |
| 228 | } |
| 229 | reqsk_put(req); |
| 230 | } |
| 231 | EXPORT_SYMBOL(dccp_req_err); |
| 232 | |
| 233 | /* |
| 234 | * This routine is called by the ICMP module when it gets some sort of error |
| 235 | * condition. If err < 0 then the socket should be closed and the error |
| 236 | * returned to the user. If err > 0 it's just the icmp type << 8 | icmp code. |
| 237 | * After adjustment header points to the first 8 bytes of the tcp header. We |
| 238 | * need to find the appropriate port. |
| 239 | * |
| 240 | * The locking strategy used here is very "optimistic". When someone else |
| 241 | * accesses the socket the ICMP is just dropped and for some paths there is no |
| 242 | * check at all. A more general error queue to queue errors for later handling |
| 243 | * is probably better. |
| 244 | */ |
| 245 | static int dccp_v4_err(struct sk_buff *skb, u32 info) |
| 246 | { |
| 247 | const struct iphdr *iph = (struct iphdr *)skb->data; |
| 248 | const u8 offset = iph->ihl << 2; |
| 249 | const struct dccp_hdr *dh; |
| 250 | struct dccp_sock *dp; |
| 251 | const int type = icmp_hdr(skb)->type; |
| 252 | const int code = icmp_hdr(skb)->code; |
| 253 | struct sock *sk; |
| 254 | __u64 seq; |
| 255 | int err; |
| 256 | struct net *net = dev_net(skb->dev); |
| 257 | |
| 258 | if (!pskb_may_pull(skb, offset + sizeof(*dh))) |
| 259 | return -EINVAL; |
| 260 | dh = (struct dccp_hdr *)(skb->data + offset); |
| 261 | if (!pskb_may_pull(skb, offset + __dccp_basic_hdr_len(dh))) |
| 262 | return -EINVAL; |
| 263 | iph = (struct iphdr *)skb->data; |
| 264 | dh = (struct dccp_hdr *)(skb->data + offset); |
| 265 | |
| 266 | sk = __inet_lookup_established(net, &dccp_hashinfo, |
| 267 | iph->daddr, dh->dccph_dport, |
| 268 | iph->saddr, ntohs(dh->dccph_sport), |
| 269 | inet_iif(skb), 0); |
| 270 | if (!sk) { |
| 271 | __ICMP_INC_STATS(net, ICMP_MIB_INERRORS); |
| 272 | return -ENOENT; |
| 273 | } |
| 274 | |
| 275 | if (sk->sk_state == DCCP_TIME_WAIT) { |
| 276 | inet_twsk_put(inet_twsk(sk)); |
| 277 | return 0; |
| 278 | } |
| 279 | seq = dccp_hdr_seq(dh); |
| 280 | if (sk->sk_state == DCCP_NEW_SYN_RECV) { |
| 281 | dccp_req_err(sk, seq); |
| 282 | return 0; |
| 283 | } |
| 284 | |
| 285 | bh_lock_sock(sk); |
| 286 | /* If too many ICMPs get dropped on busy |
| 287 | * servers this needs to be solved differently. |
| 288 | */ |
| 289 | if (sock_owned_by_user(sk)) |
| 290 | __NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS); |
| 291 | |
| 292 | if (sk->sk_state == DCCP_CLOSED) |
| 293 | goto out; |
| 294 | |
| 295 | dp = dccp_sk(sk); |
| 296 | if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_LISTEN) && |
| 297 | !between48(seq, dp->dccps_awl, dp->dccps_awh)) { |
| 298 | __NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS); |
| 299 | goto out; |
| 300 | } |
| 301 | |
| 302 | switch (type) { |
| 303 | case ICMP_REDIRECT: |
| 304 | if (!sock_owned_by_user(sk)) |
| 305 | dccp_do_redirect(skb, sk); |
| 306 | goto out; |
| 307 | case ICMP_SOURCE_QUENCH: |
| 308 | /* Just silently ignore these. */ |
| 309 | goto out; |
| 310 | case ICMP_PARAMETERPROB: |
| 311 | err = EPROTO; |
| 312 | break; |
| 313 | case ICMP_DEST_UNREACH: |
| 314 | if (code > NR_ICMP_UNREACH) |
| 315 | goto out; |
| 316 | |
| 317 | if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */ |
| 318 | if (!sock_owned_by_user(sk)) |
| 319 | dccp_do_pmtu_discovery(sk, iph, info); |
| 320 | goto out; |
| 321 | } |
| 322 | |
| 323 | err = icmp_err_convert[code].errno; |
| 324 | break; |
| 325 | case ICMP_TIME_EXCEEDED: |
| 326 | err = EHOSTUNREACH; |
| 327 | break; |
| 328 | default: |
| 329 | goto out; |
| 330 | } |
| 331 | |
| 332 | switch (sk->sk_state) { |
| 333 | case DCCP_REQUESTING: |
| 334 | case DCCP_RESPOND: |
| 335 | if (!sock_owned_by_user(sk)) { |
| 336 | __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS); |
| 337 | sk->sk_err = err; |
| 338 | |
| 339 | sk_error_report(sk); |
| 340 | |
| 341 | dccp_done(sk); |
| 342 | } else { |
| 343 | WRITE_ONCE(sk->sk_err_soft, err); |
| 344 | } |
| 345 | goto out; |
| 346 | } |
| 347 | |
| 348 | /* If we've already connected we will keep trying |
| 349 | * until we time out, or the user gives up. |
| 350 | * |
| 351 | * rfc1122 4.2.3.9 allows to consider as hard errors |
| 352 | * only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too, |
| 353 | * but it is obsoleted by pmtu discovery). |
| 354 | * |
| 355 | * Note, that in modern internet, where routing is unreliable |
| 356 | * and in each dark corner broken firewalls sit, sending random |
| 357 | * errors ordered by their masters even this two messages finally lose |
| 358 | * their original sense (even Linux sends invalid PORT_UNREACHs) |
| 359 | * |
| 360 | * Now we are in compliance with RFCs. |
| 361 | * --ANK (980905) |
| 362 | */ |
| 363 | |
| 364 | if (!sock_owned_by_user(sk) && inet_test_bit(RECVERR, sk)) { |
| 365 | sk->sk_err = err; |
| 366 | sk_error_report(sk); |
| 367 | } else { /* Only an error on timeout */ |
| 368 | WRITE_ONCE(sk->sk_err_soft, err); |
| 369 | } |
| 370 | out: |
| 371 | bh_unlock_sock(sk); |
| 372 | sock_put(sk); |
| 373 | return 0; |
| 374 | } |
| 375 | |
| 376 | static inline __sum16 dccp_v4_csum_finish(struct sk_buff *skb, |
| 377 | __be32 src, __be32 dst) |
| 378 | { |
| 379 | return csum_tcpudp_magic(src, dst, skb->len, IPPROTO_DCCP, skb->csum); |
| 380 | } |
| 381 | |
| 382 | void dccp_v4_send_check(struct sock *sk, struct sk_buff *skb) |
| 383 | { |
| 384 | const struct inet_sock *inet = inet_sk(sk); |
| 385 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 386 | |
| 387 | dccp_csum_outgoing(skb); |
| 388 | dh->dccph_checksum = dccp_v4_csum_finish(skb, |
| 389 | inet->inet_saddr, |
| 390 | inet->inet_daddr); |
| 391 | } |
| 392 | EXPORT_SYMBOL_GPL(dccp_v4_send_check); |
| 393 | |
| 394 | static inline u64 dccp_v4_init_sequence(const struct sk_buff *skb) |
| 395 | { |
| 396 | return secure_dccp_sequence_number(ip_hdr(skb)->daddr, |
| 397 | ip_hdr(skb)->saddr, |
| 398 | dccp_hdr(skb)->dccph_dport, |
| 399 | dccp_hdr(skb)->dccph_sport); |
| 400 | } |
| 401 | |
| 402 | /* |
| 403 | * The three way handshake has completed - we got a valid ACK or DATAACK - |
| 404 | * now create the new socket. |
| 405 | * |
| 406 | * This is the equivalent of TCP's tcp_v4_syn_recv_sock |
| 407 | */ |
| 408 | struct sock *dccp_v4_request_recv_sock(const struct sock *sk, |
| 409 | struct sk_buff *skb, |
| 410 | struct request_sock *req, |
| 411 | struct dst_entry *dst, |
| 412 | struct request_sock *req_unhash, |
| 413 | bool *own_req) |
| 414 | { |
| 415 | struct inet_request_sock *ireq; |
| 416 | struct inet_sock *newinet; |
| 417 | struct sock *newsk; |
| 418 | |
| 419 | if (sk_acceptq_is_full(sk)) |
| 420 | goto exit_overflow; |
| 421 | |
| 422 | newsk = dccp_create_openreq_child(sk, req, skb); |
| 423 | if (newsk == NULL) |
| 424 | goto exit_nonewsk; |
| 425 | |
| 426 | newinet = inet_sk(newsk); |
| 427 | ireq = inet_rsk(req); |
| 428 | sk_daddr_set(newsk, ireq->ir_rmt_addr); |
| 429 | sk_rcv_saddr_set(newsk, ireq->ir_loc_addr); |
| 430 | newinet->inet_saddr = ireq->ir_loc_addr; |
| 431 | RCU_INIT_POINTER(newinet->inet_opt, rcu_dereference(ireq->ireq_opt)); |
| 432 | newinet->mc_index = inet_iif(skb); |
| 433 | newinet->mc_ttl = ip_hdr(skb)->ttl; |
| 434 | atomic_set(&newinet->inet_id, get_random_u16()); |
| 435 | |
| 436 | if (dst == NULL && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL) |
| 437 | goto put_and_exit; |
| 438 | |
| 439 | sk_setup_caps(newsk, dst); |
| 440 | |
| 441 | dccp_sync_mss(newsk, dst_mtu(dst)); |
| 442 | |
| 443 | if (__inet_inherit_port(sk, newsk) < 0) |
| 444 | goto put_and_exit; |
| 445 | *own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash), NULL); |
| 446 | if (*own_req) |
| 447 | ireq->ireq_opt = NULL; |
| 448 | else |
| 449 | newinet->inet_opt = NULL; |
| 450 | return newsk; |
| 451 | |
| 452 | exit_overflow: |
| 453 | __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); |
| 454 | exit_nonewsk: |
| 455 | dst_release(dst); |
| 456 | exit: |
| 457 | __NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENDROPS); |
| 458 | return NULL; |
| 459 | put_and_exit: |
| 460 | newinet->inet_opt = NULL; |
| 461 | inet_csk_prepare_forced_close(newsk); |
| 462 | dccp_done(newsk); |
| 463 | goto exit; |
| 464 | } |
| 465 | EXPORT_SYMBOL_GPL(dccp_v4_request_recv_sock); |
| 466 | |
| 467 | static struct dst_entry* dccp_v4_route_skb(struct net *net, struct sock *sk, |
| 468 | struct sk_buff *skb) |
| 469 | { |
| 470 | struct rtable *rt; |
| 471 | const struct iphdr *iph = ip_hdr(skb); |
| 472 | struct flowi4 fl4 = { |
| 473 | .flowi4_oif = inet_iif(skb), |
| 474 | .daddr = iph->saddr, |
| 475 | .saddr = iph->daddr, |
| 476 | .flowi4_tos = ip_sock_rt_tos(sk), |
| 477 | .flowi4_scope = ip_sock_rt_scope(sk), |
| 478 | .flowi4_proto = sk->sk_protocol, |
| 479 | .fl4_sport = dccp_hdr(skb)->dccph_dport, |
| 480 | .fl4_dport = dccp_hdr(skb)->dccph_sport, |
| 481 | }; |
| 482 | |
| 483 | security_skb_classify_flow(skb, flowi4_to_flowi_common(&fl4)); |
| 484 | rt = ip_route_output_flow(net, &fl4, sk); |
| 485 | if (IS_ERR(rt)) { |
| 486 | IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); |
| 487 | return NULL; |
| 488 | } |
| 489 | |
| 490 | return &rt->dst; |
| 491 | } |
| 492 | |
| 493 | static int dccp_v4_send_response(const struct sock *sk, struct request_sock *req) |
| 494 | { |
| 495 | int err = -1; |
| 496 | struct sk_buff *skb; |
| 497 | struct dst_entry *dst; |
| 498 | struct flowi4 fl4; |
| 499 | |
| 500 | dst = inet_csk_route_req(sk, &fl4, req); |
| 501 | if (dst == NULL) |
| 502 | goto out; |
| 503 | |
| 504 | skb = dccp_make_response(sk, dst, req); |
| 505 | if (skb != NULL) { |
| 506 | const struct inet_request_sock *ireq = inet_rsk(req); |
| 507 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 508 | |
| 509 | dh->dccph_checksum = dccp_v4_csum_finish(skb, ireq->ir_loc_addr, |
| 510 | ireq->ir_rmt_addr); |
| 511 | rcu_read_lock(); |
| 512 | err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr, |
| 513 | ireq->ir_rmt_addr, |
| 514 | rcu_dereference(ireq->ireq_opt), |
| 515 | READ_ONCE(inet_sk(sk)->tos)); |
| 516 | rcu_read_unlock(); |
| 517 | err = net_xmit_eval(err); |
| 518 | } |
| 519 | |
| 520 | out: |
| 521 | dst_release(dst); |
| 522 | return err; |
| 523 | } |
| 524 | |
| 525 | static void dccp_v4_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb, |
| 526 | enum sk_rst_reason reason) |
| 527 | { |
| 528 | int err; |
| 529 | const struct iphdr *rxiph; |
| 530 | struct sk_buff *skb; |
| 531 | struct dst_entry *dst; |
| 532 | struct net *net = dev_net(skb_dst(rxskb)->dev); |
| 533 | struct dccp_v4_pernet *pn; |
| 534 | struct sock *ctl_sk; |
| 535 | |
| 536 | /* Never send a reset in response to a reset. */ |
| 537 | if (dccp_hdr(rxskb)->dccph_type == DCCP_PKT_RESET) |
| 538 | return; |
| 539 | |
| 540 | if (skb_rtable(rxskb)->rt_type != RTN_LOCAL) |
| 541 | return; |
| 542 | |
| 543 | pn = net_generic(net, dccp_v4_pernet_id); |
| 544 | ctl_sk = pn->v4_ctl_sk; |
| 545 | dst = dccp_v4_route_skb(net, ctl_sk, rxskb); |
| 546 | if (dst == NULL) |
| 547 | return; |
| 548 | |
| 549 | skb = dccp_ctl_make_reset(ctl_sk, rxskb); |
| 550 | if (skb == NULL) |
| 551 | goto out; |
| 552 | |
| 553 | rxiph = ip_hdr(rxskb); |
| 554 | dccp_hdr(skb)->dccph_checksum = dccp_v4_csum_finish(skb, rxiph->saddr, |
| 555 | rxiph->daddr); |
| 556 | skb_dst_set(skb, dst_clone(dst)); |
| 557 | |
| 558 | local_bh_disable(); |
| 559 | bh_lock_sock(ctl_sk); |
| 560 | err = ip_build_and_send_pkt(skb, ctl_sk, |
| 561 | rxiph->daddr, rxiph->saddr, NULL, |
| 562 | inet_sk(ctl_sk)->tos); |
| 563 | bh_unlock_sock(ctl_sk); |
| 564 | |
| 565 | if (net_xmit_eval(err) == 0) { |
| 566 | __DCCP_INC_STATS(DCCP_MIB_OUTSEGS); |
| 567 | __DCCP_INC_STATS(DCCP_MIB_OUTRSTS); |
| 568 | } |
| 569 | local_bh_enable(); |
| 570 | out: |
| 571 | dst_release(dst); |
| 572 | } |
| 573 | |
| 574 | static void dccp_v4_reqsk_destructor(struct request_sock *req) |
| 575 | { |
| 576 | dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg); |
| 577 | kfree(rcu_dereference_protected(inet_rsk(req)->ireq_opt, 1)); |
| 578 | } |
| 579 | |
| 580 | void dccp_syn_ack_timeout(const struct request_sock *req) |
| 581 | { |
| 582 | } |
| 583 | EXPORT_SYMBOL(dccp_syn_ack_timeout); |
| 584 | |
| 585 | static struct request_sock_ops dccp_request_sock_ops __read_mostly = { |
| 586 | .family = PF_INET, |
| 587 | .obj_size = sizeof(struct dccp_request_sock), |
| 588 | .rtx_syn_ack = dccp_v4_send_response, |
| 589 | .send_ack = dccp_reqsk_send_ack, |
| 590 | .destructor = dccp_v4_reqsk_destructor, |
| 591 | .send_reset = dccp_v4_ctl_send_reset, |
| 592 | .syn_ack_timeout = dccp_syn_ack_timeout, |
| 593 | }; |
| 594 | |
| 595 | int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb) |
| 596 | { |
| 597 | struct inet_request_sock *ireq; |
| 598 | struct request_sock *req; |
| 599 | struct dccp_request_sock *dreq; |
| 600 | const __be32 service = dccp_hdr_request(skb)->dccph_req_service; |
| 601 | struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb); |
| 602 | |
| 603 | /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */ |
| 604 | if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) |
| 605 | return 0; /* discard, don't send a reset here */ |
| 606 | |
| 607 | if (dccp_bad_service_code(sk, service)) { |
| 608 | dcb->dccpd_reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE; |
| 609 | goto drop; |
| 610 | } |
| 611 | /* |
| 612 | * TW buckets are converted to open requests without |
| 613 | * limitations, they conserve resources and peer is |
| 614 | * evidently real one. |
| 615 | */ |
| 616 | dcb->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; |
| 617 | if (inet_csk_reqsk_queue_is_full(sk)) |
| 618 | goto drop; |
| 619 | |
| 620 | if (sk_acceptq_is_full(sk)) |
| 621 | goto drop; |
| 622 | |
| 623 | req = inet_reqsk_alloc(&dccp_request_sock_ops, sk, true); |
| 624 | if (req == NULL) |
| 625 | goto drop; |
| 626 | |
| 627 | if (dccp_reqsk_init(req, dccp_sk(sk), skb)) |
| 628 | goto drop_and_free; |
| 629 | |
| 630 | dreq = dccp_rsk(req); |
| 631 | if (dccp_parse_options(sk, dreq, skb)) |
| 632 | goto drop_and_free; |
| 633 | |
| 634 | ireq = inet_rsk(req); |
| 635 | sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); |
| 636 | sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); |
| 637 | ireq->ir_mark = inet_request_mark(sk, skb); |
| 638 | ireq->ireq_family = AF_INET; |
| 639 | ireq->ir_iif = READ_ONCE(sk->sk_bound_dev_if); |
| 640 | |
| 641 | if (security_inet_conn_request(sk, skb, req)) |
| 642 | goto drop_and_free; |
| 643 | |
| 644 | /* |
| 645 | * Step 3: Process LISTEN state |
| 646 | * |
| 647 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie |
| 648 | * |
| 649 | * Setting S.SWL/S.SWH to is deferred to dccp_create_openreq_child(). |
| 650 | */ |
| 651 | dreq->dreq_isr = dcb->dccpd_seq; |
| 652 | dreq->dreq_gsr = dreq->dreq_isr; |
| 653 | dreq->dreq_iss = dccp_v4_init_sequence(skb); |
| 654 | dreq->dreq_gss = dreq->dreq_iss; |
| 655 | dreq->dreq_service = service; |
| 656 | |
| 657 | if (dccp_v4_send_response(sk, req)) |
| 658 | goto drop_and_free; |
| 659 | |
| 660 | if (unlikely(!inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT))) |
| 661 | reqsk_free(req); |
| 662 | else |
| 663 | reqsk_put(req); |
| 664 | |
| 665 | return 0; |
| 666 | |
| 667 | drop_and_free: |
| 668 | reqsk_free(req); |
| 669 | drop: |
| 670 | __DCCP_INC_STATS(DCCP_MIB_ATTEMPTFAILS); |
| 671 | return -1; |
| 672 | } |
| 673 | EXPORT_SYMBOL_GPL(dccp_v4_conn_request); |
| 674 | |
| 675 | int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb) |
| 676 | { |
| 677 | struct dccp_hdr *dh = dccp_hdr(skb); |
| 678 | |
| 679 | if (sk->sk_state == DCCP_OPEN) { /* Fast path */ |
| 680 | if (dccp_rcv_established(sk, skb, dh, skb->len)) |
| 681 | goto reset; |
| 682 | return 0; |
| 683 | } |
| 684 | |
| 685 | /* |
| 686 | * Step 3: Process LISTEN state |
| 687 | * If P.type == Request or P contains a valid Init Cookie option, |
| 688 | * (* Must scan the packet's options to check for Init |
| 689 | * Cookies. Only Init Cookies are processed here, |
| 690 | * however; other options are processed in Step 8. This |
| 691 | * scan need only be performed if the endpoint uses Init |
| 692 | * Cookies *) |
| 693 | * (* Generate a new socket and switch to that socket *) |
| 694 | * Set S := new socket for this port pair |
| 695 | * S.state = RESPOND |
| 696 | * Choose S.ISS (initial seqno) or set from Init Cookies |
| 697 | * Initialize S.GAR := S.ISS |
| 698 | * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies |
| 699 | * Continue with S.state == RESPOND |
| 700 | * (* A Response packet will be generated in Step 11 *) |
| 701 | * Otherwise, |
| 702 | * Generate Reset(No Connection) unless P.type == Reset |
| 703 | * Drop packet and return |
| 704 | * |
| 705 | * NOTE: the check for the packet types is done in |
| 706 | * dccp_rcv_state_process |
| 707 | */ |
| 708 | |
| 709 | if (dccp_rcv_state_process(sk, skb, dh, skb->len)) |
| 710 | goto reset; |
| 711 | return 0; |
| 712 | |
| 713 | reset: |
| 714 | dccp_v4_ctl_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED); |
| 715 | kfree_skb(skb); |
| 716 | return 0; |
| 717 | } |
| 718 | EXPORT_SYMBOL_GPL(dccp_v4_do_rcv); |
| 719 | |
| 720 | /** |
| 721 | * dccp_invalid_packet - check for malformed packets |
| 722 | * @skb: Packet to validate |
| 723 | * |
| 724 | * Implements RFC 4340, 8.5: Step 1: Check header basics |
| 725 | * Packets that fail these checks are ignored and do not receive Resets. |
| 726 | */ |
| 727 | int dccp_invalid_packet(struct sk_buff *skb) |
| 728 | { |
| 729 | const struct dccp_hdr *dh; |
| 730 | unsigned int cscov; |
| 731 | u8 dccph_doff; |
| 732 | |
| 733 | if (skb->pkt_type != PACKET_HOST) |
| 734 | return 1; |
| 735 | |
| 736 | /* If the packet is shorter than 12 bytes, drop packet and return */ |
| 737 | if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) { |
| 738 | DCCP_WARN("pskb_may_pull failed\n"); |
| 739 | return 1; |
| 740 | } |
| 741 | |
| 742 | dh = dccp_hdr(skb); |
| 743 | |
| 744 | /* If P.type is not understood, drop packet and return */ |
| 745 | if (dh->dccph_type >= DCCP_PKT_INVALID) { |
| 746 | DCCP_WARN("invalid packet type\n"); |
| 747 | return 1; |
| 748 | } |
| 749 | |
| 750 | /* |
| 751 | * If P.Data Offset is too small for packet type, drop packet and return |
| 752 | */ |
| 753 | dccph_doff = dh->dccph_doff; |
| 754 | if (dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) { |
| 755 | DCCP_WARN("P.Data Offset(%u) too small\n", dccph_doff); |
| 756 | return 1; |
| 757 | } |
| 758 | /* |
| 759 | * If P.Data Offset is too large for packet, drop packet and return |
| 760 | */ |
| 761 | if (!pskb_may_pull(skb, dccph_doff * sizeof(u32))) { |
| 762 | DCCP_WARN("P.Data Offset(%u) too large\n", dccph_doff); |
| 763 | return 1; |
| 764 | } |
| 765 | dh = dccp_hdr(skb); |
| 766 | /* |
| 767 | * If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet |
| 768 | * has short sequence numbers), drop packet and return |
| 769 | */ |
| 770 | if ((dh->dccph_type < DCCP_PKT_DATA || |
| 771 | dh->dccph_type > DCCP_PKT_DATAACK) && dh->dccph_x == 0) { |
| 772 | DCCP_WARN("P.type (%s) not Data || [Data]Ack, while P.X == 0\n", |
| 773 | dccp_packet_name(dh->dccph_type)); |
| 774 | return 1; |
| 775 | } |
| 776 | |
| 777 | /* |
| 778 | * If P.CsCov is too large for the packet size, drop packet and return. |
| 779 | * This must come _before_ checksumming (not as RFC 4340 suggests). |
| 780 | */ |
| 781 | cscov = dccp_csum_coverage(skb); |
| 782 | if (cscov > skb->len) { |
| 783 | DCCP_WARN("P.CsCov %u exceeds packet length %d\n", |
| 784 | dh->dccph_cscov, skb->len); |
| 785 | return 1; |
| 786 | } |
| 787 | |
| 788 | /* If header checksum is incorrect, drop packet and return. |
| 789 | * (This step is completed in the AF-dependent functions.) */ |
| 790 | skb->csum = skb_checksum(skb, 0, cscov, 0); |
| 791 | |
| 792 | return 0; |
| 793 | } |
| 794 | EXPORT_SYMBOL_GPL(dccp_invalid_packet); |
| 795 | |
| 796 | /* this is called when real data arrives */ |
| 797 | static int dccp_v4_rcv(struct sk_buff *skb) |
| 798 | { |
| 799 | const struct dccp_hdr *dh; |
| 800 | const struct iphdr *iph; |
| 801 | bool refcounted; |
| 802 | struct sock *sk; |
| 803 | int min_cov; |
| 804 | |
| 805 | /* Step 1: Check header basics */ |
| 806 | |
| 807 | if (dccp_invalid_packet(skb)) |
| 808 | goto discard_it; |
| 809 | |
| 810 | iph = ip_hdr(skb); |
| 811 | /* Step 1: If header checksum is incorrect, drop packet and return */ |
| 812 | if (dccp_v4_csum_finish(skb, iph->saddr, iph->daddr)) { |
| 813 | DCCP_WARN("dropped packet with invalid checksum\n"); |
| 814 | goto discard_it; |
| 815 | } |
| 816 | |
| 817 | dh = dccp_hdr(skb); |
| 818 | |
| 819 | DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(dh); |
| 820 | DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type; |
| 821 | |
| 822 | dccp_pr_debug("%8.8s src=%pI4@%-5d dst=%pI4@%-5d seq=%llu", |
| 823 | dccp_packet_name(dh->dccph_type), |
| 824 | &iph->saddr, ntohs(dh->dccph_sport), |
| 825 | &iph->daddr, ntohs(dh->dccph_dport), |
| 826 | (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq); |
| 827 | |
| 828 | if (dccp_packet_without_ack(skb)) { |
| 829 | DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ; |
| 830 | dccp_pr_debug_cat("\n"); |
| 831 | } else { |
| 832 | DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb); |
| 833 | dccp_pr_debug_cat(", ack=%llu\n", (unsigned long long) |
| 834 | DCCP_SKB_CB(skb)->dccpd_ack_seq); |
| 835 | } |
| 836 | |
| 837 | lookup: |
| 838 | sk = __inet_lookup_skb(&dccp_hashinfo, skb, __dccp_hdr_len(dh), |
| 839 | dh->dccph_sport, dh->dccph_dport, 0, &refcounted); |
| 840 | if (!sk) { |
| 841 | dccp_pr_debug("failed to look up flow ID in table and " |
| 842 | "get corresponding socket\n"); |
| 843 | goto no_dccp_socket; |
| 844 | } |
| 845 | |
| 846 | /* |
| 847 | * Step 2: |
| 848 | * ... or S.state == TIMEWAIT, |
| 849 | * Generate Reset(No Connection) unless P.type == Reset |
| 850 | * Drop packet and return |
| 851 | */ |
| 852 | if (sk->sk_state == DCCP_TIME_WAIT) { |
| 853 | dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n"); |
| 854 | inet_twsk_put(inet_twsk(sk)); |
| 855 | goto no_dccp_socket; |
| 856 | } |
| 857 | |
| 858 | if (sk->sk_state == DCCP_NEW_SYN_RECV) { |
| 859 | struct request_sock *req = inet_reqsk(sk); |
| 860 | struct sock *nsk; |
| 861 | |
| 862 | sk = req->rsk_listener; |
| 863 | if (unlikely(sk->sk_state != DCCP_LISTEN)) { |
| 864 | inet_csk_reqsk_queue_drop_and_put(sk, req); |
| 865 | goto lookup; |
| 866 | } |
| 867 | sock_hold(sk); |
| 868 | refcounted = true; |
| 869 | nsk = dccp_check_req(sk, skb, req); |
| 870 | if (!nsk) { |
| 871 | reqsk_put(req); |
| 872 | goto discard_and_relse; |
| 873 | } |
| 874 | if (nsk == sk) { |
| 875 | reqsk_put(req); |
| 876 | } else if (dccp_child_process(sk, nsk, skb)) { |
| 877 | dccp_v4_ctl_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED); |
| 878 | goto discard_and_relse; |
| 879 | } else { |
| 880 | sock_put(sk); |
| 881 | return 0; |
| 882 | } |
| 883 | } |
| 884 | /* |
| 885 | * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage |
| 886 | * o if MinCsCov = 0, only packets with CsCov = 0 are accepted |
| 887 | * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov |
| 888 | */ |
| 889 | min_cov = dccp_sk(sk)->dccps_pcrlen; |
| 890 | if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) { |
| 891 | dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n", |
| 892 | dh->dccph_cscov, min_cov); |
| 893 | /* FIXME: "Such packets SHOULD be reported using Data Dropped |
| 894 | * options (Section 11.7) with Drop Code 0, Protocol |
| 895 | * Constraints." */ |
| 896 | goto discard_and_relse; |
| 897 | } |
| 898 | |
| 899 | if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) |
| 900 | goto discard_and_relse; |
| 901 | nf_reset_ct(skb); |
| 902 | |
| 903 | return __sk_receive_skb(sk, skb, 1, dh->dccph_doff * 4, refcounted); |
| 904 | |
| 905 | no_dccp_socket: |
| 906 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) |
| 907 | goto discard_it; |
| 908 | /* |
| 909 | * Step 2: |
| 910 | * If no socket ... |
| 911 | * Generate Reset(No Connection) unless P.type == Reset |
| 912 | * Drop packet and return |
| 913 | */ |
| 914 | if (dh->dccph_type != DCCP_PKT_RESET) { |
| 915 | DCCP_SKB_CB(skb)->dccpd_reset_code = |
| 916 | DCCP_RESET_CODE_NO_CONNECTION; |
| 917 | dccp_v4_ctl_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED); |
| 918 | } |
| 919 | |
| 920 | discard_it: |
| 921 | kfree_skb(skb); |
| 922 | return 0; |
| 923 | |
| 924 | discard_and_relse: |
| 925 | if (refcounted) |
| 926 | sock_put(sk); |
| 927 | goto discard_it; |
| 928 | } |
| 929 | |
| 930 | static const struct inet_connection_sock_af_ops dccp_ipv4_af_ops = { |
| 931 | .queue_xmit = ip_queue_xmit, |
| 932 | .send_check = dccp_v4_send_check, |
| 933 | .rebuild_header = inet_sk_rebuild_header, |
| 934 | .conn_request = dccp_v4_conn_request, |
| 935 | .syn_recv_sock = dccp_v4_request_recv_sock, |
| 936 | .net_header_len = sizeof(struct iphdr), |
| 937 | .setsockopt = ip_setsockopt, |
| 938 | .getsockopt = ip_getsockopt, |
| 939 | .addr2sockaddr = inet_csk_addr2sockaddr, |
| 940 | .sockaddr_len = sizeof(struct sockaddr_in), |
| 941 | }; |
| 942 | |
| 943 | static int dccp_v4_init_sock(struct sock *sk) |
| 944 | { |
| 945 | static __u8 dccp_v4_ctl_sock_initialized; |
| 946 | int err = dccp_init_sock(sk, dccp_v4_ctl_sock_initialized); |
| 947 | |
| 948 | if (err == 0) { |
| 949 | if (unlikely(!dccp_v4_ctl_sock_initialized)) |
| 950 | dccp_v4_ctl_sock_initialized = 1; |
| 951 | inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops; |
| 952 | } |
| 953 | |
| 954 | return err; |
| 955 | } |
| 956 | |
| 957 | static struct timewait_sock_ops dccp_timewait_sock_ops = { |
| 958 | .twsk_obj_size = sizeof(struct inet_timewait_sock), |
| 959 | }; |
| 960 | |
| 961 | static struct proto dccp_v4_prot = { |
| 962 | .name = "DCCP", |
| 963 | .owner = THIS_MODULE, |
| 964 | .close = dccp_close, |
| 965 | .connect = dccp_v4_connect, |
| 966 | .disconnect = dccp_disconnect, |
| 967 | .ioctl = dccp_ioctl, |
| 968 | .init = dccp_v4_init_sock, |
| 969 | .setsockopt = dccp_setsockopt, |
| 970 | .getsockopt = dccp_getsockopt, |
| 971 | .sendmsg = dccp_sendmsg, |
| 972 | .recvmsg = dccp_recvmsg, |
| 973 | .backlog_rcv = dccp_v4_do_rcv, |
| 974 | .hash = inet_hash, |
| 975 | .unhash = inet_unhash, |
| 976 | .accept = inet_csk_accept, |
| 977 | .get_port = inet_csk_get_port, |
| 978 | .shutdown = dccp_shutdown, |
| 979 | .destroy = dccp_destroy_sock, |
| 980 | .orphan_count = &dccp_orphan_count, |
| 981 | .max_header = MAX_DCCP_HEADER, |
| 982 | .obj_size = sizeof(struct dccp_sock), |
| 983 | .slab_flags = SLAB_TYPESAFE_BY_RCU, |
| 984 | .rsk_prot = &dccp_request_sock_ops, |
| 985 | .twsk_prot = &dccp_timewait_sock_ops, |
| 986 | .h.hashinfo = &dccp_hashinfo, |
| 987 | }; |
| 988 | |
| 989 | static const struct net_protocol dccp_v4_protocol = { |
| 990 | .handler = dccp_v4_rcv, |
| 991 | .err_handler = dccp_v4_err, |
| 992 | .no_policy = 1, |
| 993 | .icmp_strict_tag_validation = 1, |
| 994 | }; |
| 995 | |
| 996 | static const struct proto_ops inet_dccp_ops = { |
| 997 | .family = PF_INET, |
| 998 | .owner = THIS_MODULE, |
| 999 | .release = inet_release, |
| 1000 | .bind = inet_bind, |
| 1001 | .connect = inet_stream_connect, |
| 1002 | .socketpair = sock_no_socketpair, |
| 1003 | .accept = inet_accept, |
| 1004 | .getname = inet_getname, |
| 1005 | /* FIXME: work on tcp_poll to rename it to inet_csk_poll */ |
| 1006 | .poll = dccp_poll, |
| 1007 | .ioctl = inet_ioctl, |
| 1008 | .gettstamp = sock_gettstamp, |
| 1009 | /* FIXME: work on inet_listen to rename it to sock_common_listen */ |
| 1010 | .listen = inet_dccp_listen, |
| 1011 | .shutdown = inet_shutdown, |
| 1012 | .setsockopt = sock_common_setsockopt, |
| 1013 | .getsockopt = sock_common_getsockopt, |
| 1014 | .sendmsg = inet_sendmsg, |
| 1015 | .recvmsg = sock_common_recvmsg, |
| 1016 | .mmap = sock_no_mmap, |
| 1017 | }; |
| 1018 | |
| 1019 | static struct inet_protosw dccp_v4_protosw = { |
| 1020 | .type = SOCK_DCCP, |
| 1021 | .protocol = IPPROTO_DCCP, |
| 1022 | .prot = &dccp_v4_prot, |
| 1023 | .ops = &inet_dccp_ops, |
| 1024 | .flags = INET_PROTOSW_ICSK, |
| 1025 | }; |
| 1026 | |
| 1027 | static int __net_init dccp_v4_init_net(struct net *net) |
| 1028 | { |
| 1029 | struct dccp_v4_pernet *pn = net_generic(net, dccp_v4_pernet_id); |
| 1030 | |
| 1031 | if (dccp_hashinfo.bhash == NULL) |
| 1032 | return -ESOCKTNOSUPPORT; |
| 1033 | |
| 1034 | return inet_ctl_sock_create(&pn->v4_ctl_sk, PF_INET, |
| 1035 | SOCK_DCCP, IPPROTO_DCCP, net); |
| 1036 | } |
| 1037 | |
| 1038 | static void __net_exit dccp_v4_exit_net(struct net *net) |
| 1039 | { |
| 1040 | struct dccp_v4_pernet *pn = net_generic(net, dccp_v4_pernet_id); |
| 1041 | |
| 1042 | inet_ctl_sock_destroy(pn->v4_ctl_sk); |
| 1043 | } |
| 1044 | |
| 1045 | static void __net_exit dccp_v4_exit_batch(struct list_head *net_exit_list) |
| 1046 | { |
| 1047 | inet_twsk_purge(&dccp_hashinfo); |
| 1048 | } |
| 1049 | |
| 1050 | static struct pernet_operations dccp_v4_ops = { |
| 1051 | .init = dccp_v4_init_net, |
| 1052 | .exit = dccp_v4_exit_net, |
| 1053 | .exit_batch = dccp_v4_exit_batch, |
| 1054 | .id = &dccp_v4_pernet_id, |
| 1055 | .size = sizeof(struct dccp_v4_pernet), |
| 1056 | }; |
| 1057 | |
| 1058 | static int __init dccp_v4_init(void) |
| 1059 | { |
| 1060 | int err = proto_register(&dccp_v4_prot, 1); |
| 1061 | |
| 1062 | if (err) |
| 1063 | goto out; |
| 1064 | |
| 1065 | inet_register_protosw(&dccp_v4_protosw); |
| 1066 | |
| 1067 | err = register_pernet_subsys(&dccp_v4_ops); |
| 1068 | if (err) |
| 1069 | goto out_destroy_ctl_sock; |
| 1070 | |
| 1071 | err = inet_add_protocol(&dccp_v4_protocol, IPPROTO_DCCP); |
| 1072 | if (err) |
| 1073 | goto out_proto_unregister; |
| 1074 | |
| 1075 | out: |
| 1076 | return err; |
| 1077 | out_proto_unregister: |
| 1078 | unregister_pernet_subsys(&dccp_v4_ops); |
| 1079 | out_destroy_ctl_sock: |
| 1080 | inet_unregister_protosw(&dccp_v4_protosw); |
| 1081 | proto_unregister(&dccp_v4_prot); |
| 1082 | goto out; |
| 1083 | } |
| 1084 | |
| 1085 | static void __exit dccp_v4_exit(void) |
| 1086 | { |
| 1087 | inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP); |
| 1088 | unregister_pernet_subsys(&dccp_v4_ops); |
| 1089 | inet_unregister_protosw(&dccp_v4_protosw); |
| 1090 | proto_unregister(&dccp_v4_prot); |
| 1091 | } |
| 1092 | |
| 1093 | module_init(dccp_v4_init); |
| 1094 | module_exit(dccp_v4_exit); |
| 1095 | |
| 1096 | /* |
| 1097 | * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33) |
| 1098 | * values directly, Also cover the case where the protocol is not specified, |
| 1099 | * i.e. net-pf-PF_INET-proto-0-type-SOCK_DCCP |
| 1100 | */ |
| 1101 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 33, 6); |
| 1102 | MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 0, 6); |
| 1103 | MODULE_LICENSE("GPL"); |
| 1104 | MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>"); |
| 1105 | MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol"); |