1 /* 2 * UDP over IPv6 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * 8 * Based on linux/ipv4/udp.c 9 * 10 * Fixes: 11 * Hideaki YOSHIFUJI : sin6_scope_id support 12 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which 13 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind 14 * a single port at the same time. 15 * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data 16 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/udp6 to seq_file. 17 * 18 * This program is free software; you can redistribute it and/or 19 * modify it under the terms of the GNU General Public License 20 * as published by the Free Software Foundation; either version 21 * 2 of the License, or (at your option) any later version. 22 */ 23 24 #include <linux/errno.h> 25 #include <linux/types.h> 26 #include <linux/socket.h> 27 #include <linux/sockios.h> 28 #include <linux/net.h> 29 #include <linux/in6.h> 30 #include <linux/netdevice.h> 31 #include <linux/if_arp.h> 32 #include <linux/ipv6.h> 33 #include <linux/icmpv6.h> 34 #include <linux/init.h> 35 #include <linux/module.h> 36 #include <linux/skbuff.h> 37 #include <linux/slab.h> 38 #include <linux/uaccess.h> 39 40 #include <net/addrconf.h> 41 #include <net/ndisc.h> 42 #include <net/protocol.h> 43 #include <net/transp_v6.h> 44 #include <net/ip6_route.h> 45 #include <net/raw.h> 46 #include <net/tcp_states.h> 47 #include <net/ip6_checksum.h> 48 #include <net/xfrm.h> 49 #include <net/inet_hashtables.h> 50 #include <net/inet6_hashtables.h> 51 #include <net/busy_poll.h> 52 #include <net/sock_reuseport.h> 53 54 #include <linux/proc_fs.h> 55 #include <linux/seq_file.h> 56 #include <trace/events/skb.h> 57 #include "udp_impl.h" 58 59 static bool udp6_lib_exact_dif_match(struct net *net, struct sk_buff *skb) 60 { 61 #if defined(CONFIG_NET_L3_MASTER_DEV) 62 if (!net->ipv4.sysctl_udp_l3mdev_accept && 63 skb && ipv6_l3mdev_skb(IP6CB(skb)->flags)) 64 return true; 65 #endif 66 return false; 67 } 68 69 static u32 udp6_ehashfn(const struct net *net, 70 const struct in6_addr *laddr, 71 const u16 lport, 72 const struct in6_addr *faddr, 73 const __be16 fport) 74 { 75 static u32 udp6_ehash_secret __read_mostly; 76 static u32 udp_ipv6_hash_secret __read_mostly; 77 78 u32 lhash, fhash; 79 80 net_get_random_once(&udp6_ehash_secret, 81 sizeof(udp6_ehash_secret)); 82 net_get_random_once(&udp_ipv6_hash_secret, 83 sizeof(udp_ipv6_hash_secret)); 84 85 lhash = (__force u32)laddr->s6_addr32[3]; 86 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret); 87 88 return __inet6_ehashfn(lhash, lport, fhash, fport, 89 udp_ipv6_hash_secret + net_hash_mix(net)); 90 } 91 92 static u32 udp6_portaddr_hash(const struct net *net, 93 const struct in6_addr *addr6, 94 unsigned int port) 95 { 96 unsigned int hash, mix = net_hash_mix(net); 97 98 if (ipv6_addr_any(addr6)) 99 hash = jhash_1word(0, mix); 100 else if (ipv6_addr_v4mapped(addr6)) 101 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix); 102 else 103 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix); 104 105 return hash ^ port; 106 } 107 108 int udp_v6_get_port(struct sock *sk, unsigned short snum) 109 { 110 unsigned int hash2_nulladdr = 111 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum); 112 unsigned int hash2_partial = 113 udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0); 114 115 /* precompute partial secondary hash */ 116 udp_sk(sk)->udp_portaddr_hash = hash2_partial; 117 return udp_lib_get_port(sk, snum, hash2_nulladdr); 118 } 119 120 static void udp_v6_rehash(struct sock *sk) 121 { 122 u16 new_hash = udp6_portaddr_hash(sock_net(sk), 123 &sk->sk_v6_rcv_saddr, 124 inet_sk(sk)->inet_num); 125 126 udp_lib_rehash(sk, new_hash); 127 } 128 129 static int compute_score(struct sock *sk, struct net *net, 130 const struct in6_addr *saddr, __be16 sport, 131 const struct in6_addr *daddr, unsigned short hnum, 132 int dif, bool exact_dif) 133 { 134 int score; 135 struct inet_sock *inet; 136 137 if (!net_eq(sock_net(sk), net) || 138 udp_sk(sk)->udp_port_hash != hnum || 139 sk->sk_family != PF_INET6) 140 return -1; 141 142 score = 0; 143 inet = inet_sk(sk); 144 145 if (inet->inet_dport) { 146 if (inet->inet_dport != sport) 147 return -1; 148 score++; 149 } 150 151 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) { 152 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr)) 153 return -1; 154 score++; 155 } 156 157 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 158 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr)) 159 return -1; 160 score++; 161 } 162 163 if (sk->sk_bound_dev_if || exact_dif) { 164 if (sk->sk_bound_dev_if != dif) 165 return -1; 166 score++; 167 } 168 169 if (sk->sk_incoming_cpu == raw_smp_processor_id()) 170 score++; 171 172 return score; 173 } 174 175 /* called with rcu_read_lock() */ 176 static struct sock *udp6_lib_lookup2(struct net *net, 177 const struct in6_addr *saddr, __be16 sport, 178 const struct in6_addr *daddr, unsigned int hnum, int dif, 179 bool exact_dif, struct udp_hslot *hslot2, 180 struct sk_buff *skb) 181 { 182 struct sock *sk, *result; 183 int score, badness, matches = 0, reuseport = 0; 184 u32 hash = 0; 185 186 result = NULL; 187 badness = -1; 188 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { 189 score = compute_score(sk, net, saddr, sport, 190 daddr, hnum, dif, exact_dif); 191 if (score > badness) { 192 reuseport = sk->sk_reuseport; 193 if (reuseport) { 194 hash = udp6_ehashfn(net, daddr, hnum, 195 saddr, sport); 196 197 result = reuseport_select_sock(sk, hash, skb, 198 sizeof(struct udphdr)); 199 if (result) 200 return result; 201 matches = 1; 202 } 203 result = sk; 204 badness = score; 205 } else if (score == badness && reuseport) { 206 matches++; 207 if (reciprocal_scale(hash, matches) == 0) 208 result = sk; 209 hash = next_pseudo_random32(hash); 210 } 211 } 212 return result; 213 } 214 215 /* rcu_read_lock() must be held */ 216 struct sock *__udp6_lib_lookup(struct net *net, 217 const struct in6_addr *saddr, __be16 sport, 218 const struct in6_addr *daddr, __be16 dport, 219 int dif, struct udp_table *udptable, 220 struct sk_buff *skb) 221 { 222 struct sock *sk, *result; 223 unsigned short hnum = ntohs(dport); 224 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask); 225 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot]; 226 bool exact_dif = udp6_lib_exact_dif_match(net, skb); 227 int score, badness, matches = 0, reuseport = 0; 228 u32 hash = 0; 229 230 if (hslot->count > 10) { 231 hash2 = udp6_portaddr_hash(net, daddr, hnum); 232 slot2 = hash2 & udptable->mask; 233 hslot2 = &udptable->hash2[slot2]; 234 if (hslot->count < hslot2->count) 235 goto begin; 236 237 result = udp6_lib_lookup2(net, saddr, sport, 238 daddr, hnum, dif, exact_dif, 239 hslot2, skb); 240 if (!result) { 241 unsigned int old_slot2 = slot2; 242 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum); 243 slot2 = hash2 & udptable->mask; 244 /* avoid searching the same slot again. */ 245 if (unlikely(slot2 == old_slot2)) 246 return result; 247 248 hslot2 = &udptable->hash2[slot2]; 249 if (hslot->count < hslot2->count) 250 goto begin; 251 252 result = udp6_lib_lookup2(net, saddr, sport, 253 daddr, hnum, dif, 254 exact_dif, hslot2, 255 skb); 256 } 257 return result; 258 } 259 begin: 260 result = NULL; 261 badness = -1; 262 sk_for_each_rcu(sk, &hslot->head) { 263 score = compute_score(sk, net, saddr, sport, daddr, hnum, dif, 264 exact_dif); 265 if (score > badness) { 266 reuseport = sk->sk_reuseport; 267 if (reuseport) { 268 hash = udp6_ehashfn(net, daddr, hnum, 269 saddr, sport); 270 result = reuseport_select_sock(sk, hash, skb, 271 sizeof(struct udphdr)); 272 if (result) 273 return result; 274 matches = 1; 275 } 276 result = sk; 277 badness = score; 278 } else if (score == badness && reuseport) { 279 matches++; 280 if (reciprocal_scale(hash, matches) == 0) 281 result = sk; 282 hash = next_pseudo_random32(hash); 283 } 284 } 285 return result; 286 } 287 EXPORT_SYMBOL_GPL(__udp6_lib_lookup); 288 289 static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb, 290 __be16 sport, __be16 dport, 291 struct udp_table *udptable) 292 { 293 const struct ipv6hdr *iph = ipv6_hdr(skb); 294 struct sock *sk; 295 296 sk = skb_steal_sock(skb); 297 if (unlikely(sk)) 298 return sk; 299 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport, 300 &iph->daddr, dport, inet6_iif(skb), 301 udptable, skb); 302 } 303 304 struct sock *udp6_lib_lookup_skb(struct sk_buff *skb, 305 __be16 sport, __be16 dport) 306 { 307 const struct ipv6hdr *iph = ipv6_hdr(skb); 308 309 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport, 310 &iph->daddr, dport, inet6_iif(skb), 311 &udp_table, skb); 312 } 313 EXPORT_SYMBOL_GPL(udp6_lib_lookup_skb); 314 315 /* Must be called under rcu_read_lock(). 316 * Does increment socket refcount. 317 */ 318 #if IS_ENABLED(CONFIG_NETFILTER_XT_MATCH_SOCKET) || \ 319 IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TPROXY) || \ 320 IS_ENABLED(CONFIG_NF_SOCKET_IPV6) 321 struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport, 322 const struct in6_addr *daddr, __be16 dport, int dif) 323 { 324 struct sock *sk; 325 326 sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport, 327 dif, &udp_table, NULL); 328 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) 329 sk = NULL; 330 return sk; 331 } 332 EXPORT_SYMBOL_GPL(udp6_lib_lookup); 333 #endif 334 335 /* 336 * This should be easy, if there is something there we 337 * return it, otherwise we block. 338 */ 339 340 int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 341 int noblock, int flags, int *addr_len) 342 { 343 struct ipv6_pinfo *np = inet6_sk(sk); 344 struct inet_sock *inet = inet_sk(sk); 345 struct sk_buff *skb; 346 unsigned int ulen, copied; 347 int peeked, peeking, off; 348 int err; 349 int is_udplite = IS_UDPLITE(sk); 350 bool checksum_valid = false; 351 int is_udp4; 352 353 if (flags & MSG_ERRQUEUE) 354 return ipv6_recv_error(sk, msg, len, addr_len); 355 356 if (np->rxpmtu && np->rxopt.bits.rxpmtu) 357 return ipv6_recv_rxpmtu(sk, msg, len, addr_len); 358 359 try_again: 360 peeking = off = sk_peek_offset(sk, flags); 361 skb = __skb_recv_udp(sk, flags, noblock, &peeked, &off, &err); 362 if (!skb) 363 return err; 364 365 ulen = udp_skb_len(skb); 366 copied = len; 367 if (copied > ulen - off) 368 copied = ulen - off; 369 else if (copied < ulen) 370 msg->msg_flags |= MSG_TRUNC; 371 372 is_udp4 = (skb->protocol == htons(ETH_P_IP)); 373 374 /* 375 * If checksum is needed at all, try to do it while copying the 376 * data. If the data is truncated, or if we only want a partial 377 * coverage checksum (UDP-Lite), do it before the copy. 378 */ 379 380 if (copied < ulen || peeking || 381 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) { 382 checksum_valid = udp_skb_csum_unnecessary(skb) || 383 !__udp_lib_checksum_complete(skb); 384 if (!checksum_valid) 385 goto csum_copy_err; 386 } 387 388 if (checksum_valid || udp_skb_csum_unnecessary(skb)) { 389 if (udp_skb_is_linear(skb)) 390 err = copy_linear_skb(skb, copied, off, &msg->msg_iter); 391 else 392 err = skb_copy_datagram_msg(skb, off, msg, copied); 393 } else { 394 err = skb_copy_and_csum_datagram_msg(skb, off, msg); 395 if (err == -EINVAL) 396 goto csum_copy_err; 397 } 398 if (unlikely(err)) { 399 if (!peeked) { 400 atomic_inc(&sk->sk_drops); 401 if (is_udp4) 402 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, 403 is_udplite); 404 else 405 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, 406 is_udplite); 407 } 408 kfree_skb(skb); 409 return err; 410 } 411 if (!peeked) { 412 if (is_udp4) 413 UDP_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS, 414 is_udplite); 415 else 416 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS, 417 is_udplite); 418 } 419 420 sock_recv_ts_and_drops(msg, sk, skb); 421 422 /* Copy the address. */ 423 if (msg->msg_name) { 424 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 425 sin6->sin6_family = AF_INET6; 426 sin6->sin6_port = udp_hdr(skb)->source; 427 sin6->sin6_flowinfo = 0; 428 429 if (is_udp4) { 430 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 431 &sin6->sin6_addr); 432 sin6->sin6_scope_id = 0; 433 } else { 434 sin6->sin6_addr = ipv6_hdr(skb)->saddr; 435 sin6->sin6_scope_id = 436 ipv6_iface_scope_id(&sin6->sin6_addr, 437 inet6_iif(skb)); 438 } 439 *addr_len = sizeof(*sin6); 440 } 441 442 if (np->rxopt.all) 443 ip6_datagram_recv_common_ctl(sk, msg, skb); 444 445 if (is_udp4) { 446 if (inet->cmsg_flags) 447 ip_cmsg_recv_offset(msg, sk, skb, 448 sizeof(struct udphdr), off); 449 } else { 450 if (np->rxopt.all) 451 ip6_datagram_recv_specific_ctl(sk, msg, skb); 452 } 453 454 err = copied; 455 if (flags & MSG_TRUNC) 456 err = ulen; 457 458 skb_consume_udp(sk, skb, peeking ? -err : err); 459 return err; 460 461 csum_copy_err: 462 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags, 463 udp_skb_destructor)) { 464 if (is_udp4) { 465 UDP_INC_STATS(sock_net(sk), 466 UDP_MIB_CSUMERRORS, is_udplite); 467 UDP_INC_STATS(sock_net(sk), 468 UDP_MIB_INERRORS, is_udplite); 469 } else { 470 UDP6_INC_STATS(sock_net(sk), 471 UDP_MIB_CSUMERRORS, is_udplite); 472 UDP6_INC_STATS(sock_net(sk), 473 UDP_MIB_INERRORS, is_udplite); 474 } 475 } 476 kfree_skb(skb); 477 478 /* starting over for a new packet, but check if we need to yield */ 479 cond_resched(); 480 msg->msg_flags &= ~MSG_TRUNC; 481 goto try_again; 482 } 483 484 void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 485 u8 type, u8 code, int offset, __be32 info, 486 struct udp_table *udptable) 487 { 488 struct ipv6_pinfo *np; 489 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; 490 const struct in6_addr *saddr = &hdr->saddr; 491 const struct in6_addr *daddr = &hdr->daddr; 492 struct udphdr *uh = (struct udphdr *)(skb->data+offset); 493 struct sock *sk; 494 int harderr; 495 int err; 496 struct net *net = dev_net(skb->dev); 497 498 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source, 499 inet6_iif(skb), udptable, skb); 500 if (!sk) { 501 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), 502 ICMP6_MIB_INERRORS); 503 return; 504 } 505 506 harderr = icmpv6_err_convert(type, code, &err); 507 np = inet6_sk(sk); 508 509 if (type == ICMPV6_PKT_TOOBIG) { 510 if (!ip6_sk_accept_pmtu(sk)) 511 goto out; 512 ip6_sk_update_pmtu(skb, sk, info); 513 if (np->pmtudisc != IPV6_PMTUDISC_DONT) 514 harderr = 1; 515 } 516 if (type == NDISC_REDIRECT) { 517 ip6_sk_redirect(skb, sk); 518 goto out; 519 } 520 521 if (!np->recverr) { 522 if (!harderr || sk->sk_state != TCP_ESTABLISHED) 523 goto out; 524 } else { 525 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1)); 526 } 527 528 sk->sk_err = err; 529 sk->sk_error_report(sk); 530 out: 531 return; 532 } 533 534 static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 535 { 536 int rc; 537 538 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 539 sock_rps_save_rxhash(sk, skb); 540 sk_mark_napi_id(sk, skb); 541 sk_incoming_cpu_update(sk); 542 } else { 543 sk_mark_napi_id_once(sk, skb); 544 } 545 546 rc = __udp_enqueue_schedule_skb(sk, skb); 547 if (rc < 0) { 548 int is_udplite = IS_UDPLITE(sk); 549 550 /* Note that an ENOMEM error is charged twice */ 551 if (rc == -ENOMEM) 552 UDP6_INC_STATS(sock_net(sk), 553 UDP_MIB_RCVBUFERRORS, is_udplite); 554 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 555 kfree_skb(skb); 556 return -1; 557 } 558 559 return 0; 560 } 561 562 static __inline__ void udpv6_err(struct sk_buff *skb, 563 struct inet6_skb_parm *opt, u8 type, 564 u8 code, int offset, __be32 info) 565 { 566 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table); 567 } 568 569 static struct static_key udpv6_encap_needed __read_mostly; 570 void udpv6_encap_enable(void) 571 { 572 if (!static_key_enabled(&udpv6_encap_needed)) 573 static_key_slow_inc(&udpv6_encap_needed); 574 } 575 EXPORT_SYMBOL(udpv6_encap_enable); 576 577 static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 578 { 579 struct udp_sock *up = udp_sk(sk); 580 int is_udplite = IS_UDPLITE(sk); 581 582 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 583 goto drop; 584 585 if (static_key_false(&udpv6_encap_needed) && up->encap_type) { 586 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); 587 588 /* 589 * This is an encapsulation socket so pass the skb to 590 * the socket's udp_encap_rcv() hook. Otherwise, just 591 * fall through and pass this up the UDP socket. 592 * up->encap_rcv() returns the following value: 593 * =0 if skb was successfully passed to the encap 594 * handler or was discarded by it. 595 * >0 if skb should be passed on to UDP. 596 * <0 if skb should be resubmitted as proto -N 597 */ 598 599 /* if we're overly short, let UDP handle it */ 600 encap_rcv = ACCESS_ONCE(up->encap_rcv); 601 if (encap_rcv) { 602 int ret; 603 604 /* Verify checksum before giving to encap */ 605 if (udp_lib_checksum_complete(skb)) 606 goto csum_error; 607 608 ret = encap_rcv(sk, skb); 609 if (ret <= 0) { 610 __UDP_INC_STATS(sock_net(sk), 611 UDP_MIB_INDATAGRAMS, 612 is_udplite); 613 return -ret; 614 } 615 } 616 617 /* FALLTHROUGH -- it's a UDP Packet */ 618 } 619 620 /* 621 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c). 622 */ 623 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { 624 625 if (up->pcrlen == 0) { /* full coverage was set */ 626 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n", 627 UDP_SKB_CB(skb)->cscov, skb->len); 628 goto drop; 629 } 630 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { 631 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n", 632 UDP_SKB_CB(skb)->cscov, up->pcrlen); 633 goto drop; 634 } 635 } 636 637 prefetch(&sk->sk_rmem_alloc); 638 if (rcu_access_pointer(sk->sk_filter) && 639 udp_lib_checksum_complete(skb)) 640 goto csum_error; 641 642 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) 643 goto drop; 644 645 udp_csum_pull_header(skb); 646 647 skb_dst_drop(skb); 648 649 return __udpv6_queue_rcv_skb(sk, skb); 650 651 csum_error: 652 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); 653 drop: 654 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 655 atomic_inc(&sk->sk_drops); 656 kfree_skb(skb); 657 return -1; 658 } 659 660 static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk, 661 __be16 loc_port, const struct in6_addr *loc_addr, 662 __be16 rmt_port, const struct in6_addr *rmt_addr, 663 int dif, unsigned short hnum) 664 { 665 struct inet_sock *inet = inet_sk(sk); 666 667 if (!net_eq(sock_net(sk), net)) 668 return false; 669 670 if (udp_sk(sk)->udp_port_hash != hnum || 671 sk->sk_family != PF_INET6 || 672 (inet->inet_dport && inet->inet_dport != rmt_port) || 673 (!ipv6_addr_any(&sk->sk_v6_daddr) && 674 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) || 675 (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) || 676 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) && 677 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))) 678 return false; 679 if (!inet6_mc_check(sk, loc_addr, rmt_addr)) 680 return false; 681 return true; 682 } 683 684 static void udp6_csum_zero_error(struct sk_buff *skb) 685 { 686 /* RFC 2460 section 8.1 says that we SHOULD log 687 * this error. Well, it is reasonable. 688 */ 689 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n", 690 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source), 691 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest)); 692 } 693 694 /* 695 * Note: called only from the BH handler context, 696 * so we don't need to lock the hashes. 697 */ 698 static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, 699 const struct in6_addr *saddr, const struct in6_addr *daddr, 700 struct udp_table *udptable, int proto) 701 { 702 struct sock *sk, *first = NULL; 703 const struct udphdr *uh = udp_hdr(skb); 704 unsigned short hnum = ntohs(uh->dest); 705 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum); 706 unsigned int offset = offsetof(typeof(*sk), sk_node); 707 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10); 708 int dif = inet6_iif(skb); 709 struct hlist_node *node; 710 struct sk_buff *nskb; 711 712 if (use_hash2) { 713 hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) & 714 udptable->mask; 715 hash2 = udp6_portaddr_hash(net, daddr, hnum) & udptable->mask; 716 start_lookup: 717 hslot = &udptable->hash2[hash2]; 718 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node); 719 } 720 721 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) { 722 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr, 723 uh->source, saddr, dif, hnum)) 724 continue; 725 /* If zero checksum and no_check is not on for 726 * the socket then skip it. 727 */ 728 if (!uh->check && !udp_sk(sk)->no_check6_rx) 729 continue; 730 if (!first) { 731 first = sk; 732 continue; 733 } 734 nskb = skb_clone(skb, GFP_ATOMIC); 735 if (unlikely(!nskb)) { 736 atomic_inc(&sk->sk_drops); 737 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS, 738 IS_UDPLITE(sk)); 739 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, 740 IS_UDPLITE(sk)); 741 continue; 742 } 743 744 if (udpv6_queue_rcv_skb(sk, nskb) > 0) 745 consume_skb(nskb); 746 } 747 748 /* Also lookup *:port if we are using hash2 and haven't done so yet. */ 749 if (use_hash2 && hash2 != hash2_any) { 750 hash2 = hash2_any; 751 goto start_lookup; 752 } 753 754 if (first) { 755 if (udpv6_queue_rcv_skb(first, skb) > 0) 756 consume_skb(skb); 757 } else { 758 kfree_skb(skb); 759 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI, 760 proto == IPPROTO_UDPLITE); 761 } 762 return 0; 763 } 764 765 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, 766 int proto) 767 { 768 const struct in6_addr *saddr, *daddr; 769 struct net *net = dev_net(skb->dev); 770 struct udphdr *uh; 771 struct sock *sk; 772 u32 ulen = 0; 773 774 if (!pskb_may_pull(skb, sizeof(struct udphdr))) 775 goto discard; 776 777 saddr = &ipv6_hdr(skb)->saddr; 778 daddr = &ipv6_hdr(skb)->daddr; 779 uh = udp_hdr(skb); 780 781 ulen = ntohs(uh->len); 782 if (ulen > skb->len) 783 goto short_packet; 784 785 if (proto == IPPROTO_UDP) { 786 /* UDP validates ulen. */ 787 788 /* Check for jumbo payload */ 789 if (ulen == 0) 790 ulen = skb->len; 791 792 if (ulen < sizeof(*uh)) 793 goto short_packet; 794 795 if (ulen < skb->len) { 796 if (pskb_trim_rcsum(skb, ulen)) 797 goto short_packet; 798 saddr = &ipv6_hdr(skb)->saddr; 799 daddr = &ipv6_hdr(skb)->daddr; 800 uh = udp_hdr(skb); 801 } 802 } 803 804 if (udp6_csum_init(skb, uh, proto)) 805 goto csum_error; 806 807 /* 808 * Multicast receive code 809 */ 810 if (ipv6_addr_is_multicast(daddr)) 811 return __udp6_lib_mcast_deliver(net, skb, 812 saddr, daddr, udptable, proto); 813 814 /* Unicast */ 815 816 /* 817 * check socket cache ... must talk to Alan about his plans 818 * for sock caches... i'll skip this for now. 819 */ 820 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable); 821 if (sk) { 822 int ret; 823 824 if (!uh->check && !udp_sk(sk)->no_check6_rx) { 825 udp6_csum_zero_error(skb); 826 goto csum_error; 827 } 828 829 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk)) 830 skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check, 831 ip6_compute_pseudo); 832 833 ret = udpv6_queue_rcv_skb(sk, skb); 834 835 /* a return value > 0 means to resubmit the input */ 836 if (ret > 0) 837 return ret; 838 839 return 0; 840 } 841 842 if (!uh->check) { 843 udp6_csum_zero_error(skb); 844 goto csum_error; 845 } 846 847 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 848 goto discard; 849 850 if (udp_lib_checksum_complete(skb)) 851 goto csum_error; 852 853 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE); 854 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 855 856 kfree_skb(skb); 857 return 0; 858 859 short_packet: 860 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n", 861 proto == IPPROTO_UDPLITE ? "-Lite" : "", 862 saddr, ntohs(uh->source), 863 ulen, skb->len, 864 daddr, ntohs(uh->dest)); 865 goto discard; 866 csum_error: 867 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE); 868 discard: 869 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); 870 kfree_skb(skb); 871 return 0; 872 } 873 874 875 static struct sock *__udp6_lib_demux_lookup(struct net *net, 876 __be16 loc_port, const struct in6_addr *loc_addr, 877 __be16 rmt_port, const struct in6_addr *rmt_addr, 878 int dif) 879 { 880 unsigned short hnum = ntohs(loc_port); 881 unsigned int hash2 = udp6_portaddr_hash(net, loc_addr, hnum); 882 unsigned int slot2 = hash2 & udp_table.mask; 883 struct udp_hslot *hslot2 = &udp_table.hash2[slot2]; 884 const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum); 885 struct sock *sk; 886 887 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { 888 if (sk->sk_state == TCP_ESTABLISHED && 889 INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif)) 890 return sk; 891 /* Only check first socket in chain */ 892 break; 893 } 894 return NULL; 895 } 896 897 static void udp_v6_early_demux(struct sk_buff *skb) 898 { 899 struct net *net = dev_net(skb->dev); 900 const struct udphdr *uh; 901 struct sock *sk; 902 struct dst_entry *dst; 903 int dif = skb->dev->ifindex; 904 905 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 906 sizeof(struct udphdr))) 907 return; 908 909 uh = udp_hdr(skb); 910 911 if (skb->pkt_type == PACKET_HOST) 912 sk = __udp6_lib_demux_lookup(net, uh->dest, 913 &ipv6_hdr(skb)->daddr, 914 uh->source, &ipv6_hdr(skb)->saddr, 915 dif); 916 else 917 return; 918 919 if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt)) 920 return; 921 922 skb->sk = sk; 923 skb->destructor = sock_efree; 924 dst = READ_ONCE(sk->sk_rx_dst); 925 926 if (dst) 927 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); 928 if (dst) { 929 /* set noref for now. 930 * any place which wants to hold dst has to call 931 * dst_hold_safe() 932 */ 933 skb_dst_set_noref(skb, dst); 934 } 935 } 936 937 static __inline__ int udpv6_rcv(struct sk_buff *skb) 938 { 939 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP); 940 } 941 942 /* 943 * Throw away all pending data and cancel the corking. Socket is locked. 944 */ 945 static void udp_v6_flush_pending_frames(struct sock *sk) 946 { 947 struct udp_sock *up = udp_sk(sk); 948 949 if (up->pending == AF_INET) 950 udp_flush_pending_frames(sk); 951 else if (up->pending) { 952 up->len = 0; 953 up->pending = 0; 954 ip6_flush_pending_frames(sk); 955 } 956 } 957 958 /** 959 * udp6_hwcsum_outgoing - handle outgoing HW checksumming 960 * @sk: socket we are sending on 961 * @skb: sk_buff containing the filled-in UDP header 962 * (checksum field must be zeroed out) 963 */ 964 static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, 965 const struct in6_addr *saddr, 966 const struct in6_addr *daddr, int len) 967 { 968 unsigned int offset; 969 struct udphdr *uh = udp_hdr(skb); 970 struct sk_buff *frags = skb_shinfo(skb)->frag_list; 971 __wsum csum = 0; 972 973 if (!frags) { 974 /* Only one fragment on the socket. */ 975 skb->csum_start = skb_transport_header(skb) - skb->head; 976 skb->csum_offset = offsetof(struct udphdr, check); 977 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0); 978 } else { 979 /* 980 * HW-checksum won't work as there are two or more 981 * fragments on the socket so that all csums of sk_buffs 982 * should be together 983 */ 984 offset = skb_transport_offset(skb); 985 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); 986 987 skb->ip_summed = CHECKSUM_NONE; 988 989 do { 990 csum = csum_add(csum, frags->csum); 991 } while ((frags = frags->next)); 992 993 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 994 csum); 995 if (uh->check == 0) 996 uh->check = CSUM_MANGLED_0; 997 } 998 } 999 1000 /* 1001 * Sending 1002 */ 1003 1004 static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6) 1005 { 1006 struct sock *sk = skb->sk; 1007 struct udphdr *uh; 1008 int err = 0; 1009 int is_udplite = IS_UDPLITE(sk); 1010 __wsum csum = 0; 1011 int offset = skb_transport_offset(skb); 1012 int len = skb->len - offset; 1013 1014 /* 1015 * Create a UDP header 1016 */ 1017 uh = udp_hdr(skb); 1018 uh->source = fl6->fl6_sport; 1019 uh->dest = fl6->fl6_dport; 1020 uh->len = htons(len); 1021 uh->check = 0; 1022 1023 if (is_udplite) 1024 csum = udplite_csum(skb); 1025 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */ 1026 skb->ip_summed = CHECKSUM_NONE; 1027 goto send; 1028 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ 1029 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len); 1030 goto send; 1031 } else 1032 csum = udp_csum(skb); 1033 1034 /* add protocol-dependent pseudo-header */ 1035 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr, 1036 len, fl6->flowi6_proto, csum); 1037 if (uh->check == 0) 1038 uh->check = CSUM_MANGLED_0; 1039 1040 send: 1041 err = ip6_send_skb(skb); 1042 if (err) { 1043 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) { 1044 UDP6_INC_STATS(sock_net(sk), 1045 UDP_MIB_SNDBUFERRORS, is_udplite); 1046 err = 0; 1047 } 1048 } else { 1049 UDP6_INC_STATS(sock_net(sk), 1050 UDP_MIB_OUTDATAGRAMS, is_udplite); 1051 } 1052 return err; 1053 } 1054 1055 static int udp_v6_push_pending_frames(struct sock *sk) 1056 { 1057 struct sk_buff *skb; 1058 struct udp_sock *up = udp_sk(sk); 1059 struct flowi6 fl6; 1060 int err = 0; 1061 1062 if (up->pending == AF_INET) 1063 return udp_push_pending_frames(sk); 1064 1065 /* ip6_finish_skb will release the cork, so make a copy of 1066 * fl6 here. 1067 */ 1068 fl6 = inet_sk(sk)->cork.fl.u.ip6; 1069 1070 skb = ip6_finish_skb(sk); 1071 if (!skb) 1072 goto out; 1073 1074 err = udp_v6_send_skb(skb, &fl6); 1075 1076 out: 1077 up->len = 0; 1078 up->pending = 0; 1079 return err; 1080 } 1081 1082 int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 1083 { 1084 struct ipv6_txoptions opt_space; 1085 struct udp_sock *up = udp_sk(sk); 1086 struct inet_sock *inet = inet_sk(sk); 1087 struct ipv6_pinfo *np = inet6_sk(sk); 1088 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 1089 struct in6_addr *daddr, *final_p, final; 1090 struct ipv6_txoptions *opt = NULL; 1091 struct ipv6_txoptions *opt_to_free = NULL; 1092 struct ip6_flowlabel *flowlabel = NULL; 1093 struct flowi6 fl6; 1094 struct dst_entry *dst; 1095 struct ipcm6_cookie ipc6; 1096 int addr_len = msg->msg_namelen; 1097 int ulen = len; 1098 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; 1099 int err; 1100 int connected = 0; 1101 int is_udplite = IS_UDPLITE(sk); 1102 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); 1103 struct sockcm_cookie sockc; 1104 1105 ipc6.hlimit = -1; 1106 ipc6.tclass = -1; 1107 ipc6.dontfrag = -1; 1108 sockc.tsflags = sk->sk_tsflags; 1109 1110 /* destination address check */ 1111 if (sin6) { 1112 if (addr_len < offsetof(struct sockaddr, sa_data)) 1113 return -EINVAL; 1114 1115 switch (sin6->sin6_family) { 1116 case AF_INET6: 1117 if (addr_len < SIN6_LEN_RFC2133) 1118 return -EINVAL; 1119 daddr = &sin6->sin6_addr; 1120 if (ipv6_addr_any(daddr) && 1121 ipv6_addr_v4mapped(&np->saddr)) 1122 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK), 1123 daddr); 1124 break; 1125 case AF_INET: 1126 goto do_udp_sendmsg; 1127 case AF_UNSPEC: 1128 msg->msg_name = sin6 = NULL; 1129 msg->msg_namelen = addr_len = 0; 1130 daddr = NULL; 1131 break; 1132 default: 1133 return -EINVAL; 1134 } 1135 } else if (!up->pending) { 1136 if (sk->sk_state != TCP_ESTABLISHED) 1137 return -EDESTADDRREQ; 1138 daddr = &sk->sk_v6_daddr; 1139 } else 1140 daddr = NULL; 1141 1142 if (daddr) { 1143 if (ipv6_addr_v4mapped(daddr)) { 1144 struct sockaddr_in sin; 1145 sin.sin_family = AF_INET; 1146 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport; 1147 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 1148 msg->msg_name = &sin; 1149 msg->msg_namelen = sizeof(sin); 1150 do_udp_sendmsg: 1151 if (__ipv6_only_sock(sk)) 1152 return -ENETUNREACH; 1153 return udp_sendmsg(sk, msg, len); 1154 } 1155 } 1156 1157 if (up->pending == AF_INET) 1158 return udp_sendmsg(sk, msg, len); 1159 1160 /* Rough check on arithmetic overflow, 1161 better check is made in ip6_append_data(). 1162 */ 1163 if (len > INT_MAX - sizeof(struct udphdr)) 1164 return -EMSGSIZE; 1165 1166 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; 1167 if (up->pending) { 1168 /* 1169 * There are pending frames. 1170 * The socket lock must be held while it's corked. 1171 */ 1172 lock_sock(sk); 1173 if (likely(up->pending)) { 1174 if (unlikely(up->pending != AF_INET6)) { 1175 release_sock(sk); 1176 return -EAFNOSUPPORT; 1177 } 1178 dst = NULL; 1179 goto do_append_data; 1180 } 1181 release_sock(sk); 1182 } 1183 ulen += sizeof(struct udphdr); 1184 1185 memset(&fl6, 0, sizeof(fl6)); 1186 1187 if (sin6) { 1188 if (sin6->sin6_port == 0) 1189 return -EINVAL; 1190 1191 fl6.fl6_dport = sin6->sin6_port; 1192 daddr = &sin6->sin6_addr; 1193 1194 if (np->sndflow) { 1195 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK; 1196 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 1197 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1198 if (!flowlabel) 1199 return -EINVAL; 1200 } 1201 } 1202 1203 /* 1204 * Otherwise it will be difficult to maintain 1205 * sk->sk_dst_cache. 1206 */ 1207 if (sk->sk_state == TCP_ESTABLISHED && 1208 ipv6_addr_equal(daddr, &sk->sk_v6_daddr)) 1209 daddr = &sk->sk_v6_daddr; 1210 1211 if (addr_len >= sizeof(struct sockaddr_in6) && 1212 sin6->sin6_scope_id && 1213 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr))) 1214 fl6.flowi6_oif = sin6->sin6_scope_id; 1215 } else { 1216 if (sk->sk_state != TCP_ESTABLISHED) 1217 return -EDESTADDRREQ; 1218 1219 fl6.fl6_dport = inet->inet_dport; 1220 daddr = &sk->sk_v6_daddr; 1221 fl6.flowlabel = np->flow_label; 1222 connected = 1; 1223 } 1224 1225 if (!fl6.flowi6_oif) 1226 fl6.flowi6_oif = sk->sk_bound_dev_if; 1227 1228 if (!fl6.flowi6_oif) 1229 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; 1230 1231 fl6.flowi6_mark = sk->sk_mark; 1232 fl6.flowi6_uid = sk->sk_uid; 1233 1234 if (msg->msg_controllen) { 1235 opt = &opt_space; 1236 memset(opt, 0, sizeof(struct ipv6_txoptions)); 1237 opt->tot_len = sizeof(*opt); 1238 ipc6.opt = opt; 1239 1240 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6, &sockc); 1241 if (err < 0) { 1242 fl6_sock_release(flowlabel); 1243 return err; 1244 } 1245 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) { 1246 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1247 if (!flowlabel) 1248 return -EINVAL; 1249 } 1250 if (!(opt->opt_nflen|opt->opt_flen)) 1251 opt = NULL; 1252 connected = 0; 1253 } 1254 if (!opt) { 1255 opt = txopt_get(np); 1256 opt_to_free = opt; 1257 } 1258 if (flowlabel) 1259 opt = fl6_merge_options(&opt_space, flowlabel, opt); 1260 opt = ipv6_fixup_options(&opt_space, opt); 1261 ipc6.opt = opt; 1262 1263 fl6.flowi6_proto = sk->sk_protocol; 1264 if (!ipv6_addr_any(daddr)) 1265 fl6.daddr = *daddr; 1266 else 1267 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */ 1268 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr)) 1269 fl6.saddr = np->saddr; 1270 fl6.fl6_sport = inet->inet_sport; 1271 1272 final_p = fl6_update_dst(&fl6, opt, &final); 1273 if (final_p) 1274 connected = 0; 1275 1276 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) { 1277 fl6.flowi6_oif = np->mcast_oif; 1278 connected = 0; 1279 } else if (!fl6.flowi6_oif) 1280 fl6.flowi6_oif = np->ucast_oif; 1281 1282 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); 1283 1284 if (ipc6.tclass < 0) 1285 ipc6.tclass = np->tclass; 1286 1287 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel); 1288 1289 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p); 1290 if (IS_ERR(dst)) { 1291 err = PTR_ERR(dst); 1292 dst = NULL; 1293 goto out; 1294 } 1295 1296 if (ipc6.hlimit < 0) 1297 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst); 1298 1299 if (msg->msg_flags&MSG_CONFIRM) 1300 goto do_confirm; 1301 back_from_confirm: 1302 1303 /* Lockless fast path for the non-corking case */ 1304 if (!corkreq) { 1305 struct sk_buff *skb; 1306 1307 skb = ip6_make_skb(sk, getfrag, msg, ulen, 1308 sizeof(struct udphdr), &ipc6, 1309 &fl6, (struct rt6_info *)dst, 1310 msg->msg_flags, &sockc); 1311 err = PTR_ERR(skb); 1312 if (!IS_ERR_OR_NULL(skb)) 1313 err = udp_v6_send_skb(skb, &fl6); 1314 goto release_dst; 1315 } 1316 1317 lock_sock(sk); 1318 if (unlikely(up->pending)) { 1319 /* The socket is already corked while preparing it. */ 1320 /* ... which is an evident application bug. --ANK */ 1321 release_sock(sk); 1322 1323 net_dbg_ratelimited("udp cork app bug 2\n"); 1324 err = -EINVAL; 1325 goto out; 1326 } 1327 1328 up->pending = AF_INET6; 1329 1330 do_append_data: 1331 if (ipc6.dontfrag < 0) 1332 ipc6.dontfrag = np->dontfrag; 1333 up->len += ulen; 1334 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr), 1335 &ipc6, &fl6, (struct rt6_info *)dst, 1336 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, &sockc); 1337 if (err) 1338 udp_v6_flush_pending_frames(sk); 1339 else if (!corkreq) 1340 err = udp_v6_push_pending_frames(sk); 1341 else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) 1342 up->pending = 0; 1343 1344 if (err > 0) 1345 err = np->recverr ? net_xmit_errno(err) : 0; 1346 release_sock(sk); 1347 1348 release_dst: 1349 if (dst) { 1350 if (connected) { 1351 ip6_dst_store(sk, dst, 1352 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ? 1353 &sk->sk_v6_daddr : NULL, 1354 #ifdef CONFIG_IPV6_SUBTREES 1355 ipv6_addr_equal(&fl6.saddr, &np->saddr) ? 1356 &np->saddr : 1357 #endif 1358 NULL); 1359 } else { 1360 dst_release(dst); 1361 } 1362 dst = NULL; 1363 } 1364 1365 out: 1366 dst_release(dst); 1367 fl6_sock_release(flowlabel); 1368 txopt_put(opt_to_free); 1369 if (!err) 1370 return len; 1371 /* 1372 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting 1373 * ENOBUFS might not be good (it's not tunable per se), but otherwise 1374 * we don't have a good statistic (IpOutDiscards but it can be too many 1375 * things). We could add another new stat but at least for now that 1376 * seems like overkill. 1377 */ 1378 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { 1379 UDP6_INC_STATS(sock_net(sk), 1380 UDP_MIB_SNDBUFERRORS, is_udplite); 1381 } 1382 return err; 1383 1384 do_confirm: 1385 if (msg->msg_flags & MSG_PROBE) 1386 dst_confirm_neigh(dst, &fl6.daddr); 1387 if (!(msg->msg_flags&MSG_PROBE) || len) 1388 goto back_from_confirm; 1389 err = 0; 1390 goto out; 1391 } 1392 1393 void udpv6_destroy_sock(struct sock *sk) 1394 { 1395 struct udp_sock *up = udp_sk(sk); 1396 lock_sock(sk); 1397 udp_v6_flush_pending_frames(sk); 1398 release_sock(sk); 1399 1400 if (static_key_false(&udpv6_encap_needed) && up->encap_type) { 1401 void (*encap_destroy)(struct sock *sk); 1402 encap_destroy = ACCESS_ONCE(up->encap_destroy); 1403 if (encap_destroy) 1404 encap_destroy(sk); 1405 } 1406 1407 inet6_destroy_sock(sk); 1408 } 1409 1410 /* 1411 * Socket option code for UDP 1412 */ 1413 int udpv6_setsockopt(struct sock *sk, int level, int optname, 1414 char __user *optval, unsigned int optlen) 1415 { 1416 if (level == SOL_UDP || level == SOL_UDPLITE) 1417 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1418 udp_v6_push_pending_frames); 1419 return ipv6_setsockopt(sk, level, optname, optval, optlen); 1420 } 1421 1422 #ifdef CONFIG_COMPAT 1423 int compat_udpv6_setsockopt(struct sock *sk, int level, int optname, 1424 char __user *optval, unsigned int optlen) 1425 { 1426 if (level == SOL_UDP || level == SOL_UDPLITE) 1427 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1428 udp_v6_push_pending_frames); 1429 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen); 1430 } 1431 #endif 1432 1433 int udpv6_getsockopt(struct sock *sk, int level, int optname, 1434 char __user *optval, int __user *optlen) 1435 { 1436 if (level == SOL_UDP || level == SOL_UDPLITE) 1437 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1438 return ipv6_getsockopt(sk, level, optname, optval, optlen); 1439 } 1440 1441 #ifdef CONFIG_COMPAT 1442 int compat_udpv6_getsockopt(struct sock *sk, int level, int optname, 1443 char __user *optval, int __user *optlen) 1444 { 1445 if (level == SOL_UDP || level == SOL_UDPLITE) 1446 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1447 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen); 1448 } 1449 #endif 1450 1451 static struct inet6_protocol udpv6_protocol = { 1452 .early_demux = udp_v6_early_demux, 1453 .early_demux_handler = udp_v6_early_demux, 1454 .handler = udpv6_rcv, 1455 .err_handler = udpv6_err, 1456 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1457 }; 1458 1459 /* ------------------------------------------------------------------------ */ 1460 #ifdef CONFIG_PROC_FS 1461 int udp6_seq_show(struct seq_file *seq, void *v) 1462 { 1463 if (v == SEQ_START_TOKEN) { 1464 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER); 1465 } else { 1466 int bucket = ((struct udp_iter_state *)seq->private)->bucket; 1467 struct inet_sock *inet = inet_sk(v); 1468 __u16 srcp = ntohs(inet->inet_sport); 1469 __u16 destp = ntohs(inet->inet_dport); 1470 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket); 1471 } 1472 return 0; 1473 } 1474 1475 static const struct file_operations udp6_afinfo_seq_fops = { 1476 .owner = THIS_MODULE, 1477 .open = udp_seq_open, 1478 .read = seq_read, 1479 .llseek = seq_lseek, 1480 .release = seq_release_net 1481 }; 1482 1483 static struct udp_seq_afinfo udp6_seq_afinfo = { 1484 .name = "udp6", 1485 .family = AF_INET6, 1486 .udp_table = &udp_table, 1487 .seq_fops = &udp6_afinfo_seq_fops, 1488 .seq_ops = { 1489 .show = udp6_seq_show, 1490 }, 1491 }; 1492 1493 int __net_init udp6_proc_init(struct net *net) 1494 { 1495 return udp_proc_register(net, &udp6_seq_afinfo); 1496 } 1497 1498 void udp6_proc_exit(struct net *net) 1499 { 1500 udp_proc_unregister(net, &udp6_seq_afinfo); 1501 } 1502 #endif /* CONFIG_PROC_FS */ 1503 1504 /* ------------------------------------------------------------------------ */ 1505 1506 struct proto udpv6_prot = { 1507 .name = "UDPv6", 1508 .owner = THIS_MODULE, 1509 .close = udp_lib_close, 1510 .connect = ip6_datagram_connect, 1511 .disconnect = udp_disconnect, 1512 .ioctl = udp_ioctl, 1513 .init = udp_init_sock, 1514 .destroy = udpv6_destroy_sock, 1515 .setsockopt = udpv6_setsockopt, 1516 .getsockopt = udpv6_getsockopt, 1517 .sendmsg = udpv6_sendmsg, 1518 .recvmsg = udpv6_recvmsg, 1519 .release_cb = ip6_datagram_release_cb, 1520 .hash = udp_lib_hash, 1521 .unhash = udp_lib_unhash, 1522 .rehash = udp_v6_rehash, 1523 .get_port = udp_v6_get_port, 1524 .memory_allocated = &udp_memory_allocated, 1525 .sysctl_mem = sysctl_udp_mem, 1526 .sysctl_wmem = &sysctl_udp_wmem_min, 1527 .sysctl_rmem = &sysctl_udp_rmem_min, 1528 .obj_size = sizeof(struct udp6_sock), 1529 .h.udp_table = &udp_table, 1530 #ifdef CONFIG_COMPAT 1531 .compat_setsockopt = compat_udpv6_setsockopt, 1532 .compat_getsockopt = compat_udpv6_getsockopt, 1533 #endif 1534 .diag_destroy = udp_abort, 1535 }; 1536 1537 static struct inet_protosw udpv6_protosw = { 1538 .type = SOCK_DGRAM, 1539 .protocol = IPPROTO_UDP, 1540 .prot = &udpv6_prot, 1541 .ops = &inet6_dgram_ops, 1542 .flags = INET_PROTOSW_PERMANENT, 1543 }; 1544 1545 int __init udpv6_init(void) 1546 { 1547 int ret; 1548 1549 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP); 1550 if (ret) 1551 goto out; 1552 1553 ret = inet6_register_protosw(&udpv6_protosw); 1554 if (ret) 1555 goto out_udpv6_protocol; 1556 out: 1557 return ret; 1558 1559 out_udpv6_protocol: 1560 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1561 goto out; 1562 } 1563 1564 void udpv6_exit(void) 1565 { 1566 inet6_unregister_protosw(&udpv6_protosw); 1567 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1568 } 1569