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