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 && !atomic_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 = skb->len; 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_lib_checksum_complete(skb); 383 if (!checksum_valid) 384 goto csum_copy_err; 385 } 386 387 if (checksum_valid || skb_csum_unnecessary(skb)) 388 err = skb_copy_datagram_msg(skb, off, msg, copied); 389 else { 390 err = skb_copy_and_csum_datagram_msg(skb, off, msg); 391 if (err == -EINVAL) 392 goto csum_copy_err; 393 } 394 if (unlikely(err)) { 395 if (!peeked) { 396 atomic_inc(&sk->sk_drops); 397 if (is_udp4) 398 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, 399 is_udplite); 400 else 401 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, 402 is_udplite); 403 } 404 kfree_skb(skb); 405 return err; 406 } 407 if (!peeked) { 408 if (is_udp4) 409 UDP_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS, 410 is_udplite); 411 else 412 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INDATAGRAMS, 413 is_udplite); 414 } 415 416 sock_recv_ts_and_drops(msg, sk, skb); 417 418 /* Copy the address. */ 419 if (msg->msg_name) { 420 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 421 sin6->sin6_family = AF_INET6; 422 sin6->sin6_port = udp_hdr(skb)->source; 423 sin6->sin6_flowinfo = 0; 424 425 if (is_udp4) { 426 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 427 &sin6->sin6_addr); 428 sin6->sin6_scope_id = 0; 429 } else { 430 sin6->sin6_addr = ipv6_hdr(skb)->saddr; 431 sin6->sin6_scope_id = 432 ipv6_iface_scope_id(&sin6->sin6_addr, 433 inet6_iif(skb)); 434 } 435 *addr_len = sizeof(*sin6); 436 } 437 438 if (np->rxopt.all) 439 ip6_datagram_recv_common_ctl(sk, msg, skb); 440 441 if (is_udp4) { 442 if (inet->cmsg_flags) 443 ip_cmsg_recv_offset(msg, sk, skb, 444 sizeof(struct udphdr), off); 445 } else { 446 if (np->rxopt.all) 447 ip6_datagram_recv_specific_ctl(sk, msg, skb); 448 } 449 450 err = copied; 451 if (flags & MSG_TRUNC) 452 err = ulen; 453 454 skb_consume_udp(sk, skb, peeking ? -err : err); 455 return err; 456 457 csum_copy_err: 458 if (!__sk_queue_drop_skb(sk, skb, flags, udp_skb_destructor)) { 459 if (is_udp4) { 460 UDP_INC_STATS(sock_net(sk), 461 UDP_MIB_CSUMERRORS, is_udplite); 462 UDP_INC_STATS(sock_net(sk), 463 UDP_MIB_INERRORS, is_udplite); 464 } else { 465 UDP6_INC_STATS(sock_net(sk), 466 UDP_MIB_CSUMERRORS, is_udplite); 467 UDP6_INC_STATS(sock_net(sk), 468 UDP_MIB_INERRORS, is_udplite); 469 } 470 } 471 kfree_skb(skb); 472 473 /* starting over for a new packet, but check if we need to yield */ 474 cond_resched(); 475 msg->msg_flags &= ~MSG_TRUNC; 476 goto try_again; 477 } 478 479 void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 480 u8 type, u8 code, int offset, __be32 info, 481 struct udp_table *udptable) 482 { 483 struct ipv6_pinfo *np; 484 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; 485 const struct in6_addr *saddr = &hdr->saddr; 486 const struct in6_addr *daddr = &hdr->daddr; 487 struct udphdr *uh = (struct udphdr *)(skb->data+offset); 488 struct sock *sk; 489 int harderr; 490 int err; 491 struct net *net = dev_net(skb->dev); 492 493 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source, 494 inet6_iif(skb), udptable, skb); 495 if (!sk) { 496 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), 497 ICMP6_MIB_INERRORS); 498 return; 499 } 500 501 harderr = icmpv6_err_convert(type, code, &err); 502 np = inet6_sk(sk); 503 504 if (type == ICMPV6_PKT_TOOBIG) { 505 if (!ip6_sk_accept_pmtu(sk)) 506 goto out; 507 ip6_sk_update_pmtu(skb, sk, info); 508 if (np->pmtudisc != IPV6_PMTUDISC_DONT) 509 harderr = 1; 510 } 511 if (type == NDISC_REDIRECT) { 512 ip6_sk_redirect(skb, sk); 513 goto out; 514 } 515 516 if (!np->recverr) { 517 if (!harderr || sk->sk_state != TCP_ESTABLISHED) 518 goto out; 519 } else { 520 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1)); 521 } 522 523 sk->sk_err = err; 524 sk->sk_error_report(sk); 525 out: 526 return; 527 } 528 529 static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 530 { 531 int rc; 532 533 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 534 sock_rps_save_rxhash(sk, skb); 535 sk_mark_napi_id(sk, skb); 536 sk_incoming_cpu_update(sk); 537 } else { 538 sk_mark_napi_id_once(sk, skb); 539 } 540 541 rc = __udp_enqueue_schedule_skb(sk, skb); 542 if (rc < 0) { 543 int is_udplite = IS_UDPLITE(sk); 544 545 /* Note that an ENOMEM error is charged twice */ 546 if (rc == -ENOMEM) 547 UDP6_INC_STATS(sock_net(sk), 548 UDP_MIB_RCVBUFERRORS, is_udplite); 549 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 550 kfree_skb(skb); 551 return -1; 552 } 553 554 return 0; 555 } 556 557 static __inline__ void udpv6_err(struct sk_buff *skb, 558 struct inet6_skb_parm *opt, u8 type, 559 u8 code, int offset, __be32 info) 560 { 561 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table); 562 } 563 564 static struct static_key udpv6_encap_needed __read_mostly; 565 void udpv6_encap_enable(void) 566 { 567 if (!static_key_enabled(&udpv6_encap_needed)) 568 static_key_slow_inc(&udpv6_encap_needed); 569 } 570 EXPORT_SYMBOL(udpv6_encap_enable); 571 572 static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 573 { 574 struct udp_sock *up = udp_sk(sk); 575 int is_udplite = IS_UDPLITE(sk); 576 577 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 578 goto drop; 579 580 if (static_key_false(&udpv6_encap_needed) && up->encap_type) { 581 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); 582 583 /* 584 * This is an encapsulation socket so pass the skb to 585 * the socket's udp_encap_rcv() hook. Otherwise, just 586 * fall through and pass this up the UDP socket. 587 * up->encap_rcv() returns the following value: 588 * =0 if skb was successfully passed to the encap 589 * handler or was discarded by it. 590 * >0 if skb should be passed on to UDP. 591 * <0 if skb should be resubmitted as proto -N 592 */ 593 594 /* if we're overly short, let UDP handle it */ 595 encap_rcv = ACCESS_ONCE(up->encap_rcv); 596 if (encap_rcv) { 597 int ret; 598 599 /* Verify checksum before giving to encap */ 600 if (udp_lib_checksum_complete(skb)) 601 goto csum_error; 602 603 ret = encap_rcv(sk, skb); 604 if (ret <= 0) { 605 __UDP_INC_STATS(sock_net(sk), 606 UDP_MIB_INDATAGRAMS, 607 is_udplite); 608 return -ret; 609 } 610 } 611 612 /* FALLTHROUGH -- it's a UDP Packet */ 613 } 614 615 /* 616 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c). 617 */ 618 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { 619 620 if (up->pcrlen == 0) { /* full coverage was set */ 621 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n", 622 UDP_SKB_CB(skb)->cscov, skb->len); 623 goto drop; 624 } 625 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { 626 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n", 627 UDP_SKB_CB(skb)->cscov, up->pcrlen); 628 goto drop; 629 } 630 } 631 632 if (rcu_access_pointer(sk->sk_filter) && 633 udp_lib_checksum_complete(skb)) 634 goto csum_error; 635 636 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) 637 goto drop; 638 639 udp_csum_pull_header(skb); 640 641 skb_dst_drop(skb); 642 643 return __udpv6_queue_rcv_skb(sk, skb); 644 645 csum_error: 646 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); 647 drop: 648 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 649 atomic_inc(&sk->sk_drops); 650 kfree_skb(skb); 651 return -1; 652 } 653 654 static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk, 655 __be16 loc_port, const struct in6_addr *loc_addr, 656 __be16 rmt_port, const struct in6_addr *rmt_addr, 657 int dif, unsigned short hnum) 658 { 659 struct inet_sock *inet = inet_sk(sk); 660 661 if (!net_eq(sock_net(sk), net)) 662 return false; 663 664 if (udp_sk(sk)->udp_port_hash != hnum || 665 sk->sk_family != PF_INET6 || 666 (inet->inet_dport && inet->inet_dport != rmt_port) || 667 (!ipv6_addr_any(&sk->sk_v6_daddr) && 668 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) || 669 (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) || 670 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) && 671 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))) 672 return false; 673 if (!inet6_mc_check(sk, loc_addr, rmt_addr)) 674 return false; 675 return true; 676 } 677 678 static void udp6_csum_zero_error(struct sk_buff *skb) 679 { 680 /* RFC 2460 section 8.1 says that we SHOULD log 681 * this error. Well, it is reasonable. 682 */ 683 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n", 684 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source), 685 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest)); 686 } 687 688 /* 689 * Note: called only from the BH handler context, 690 * so we don't need to lock the hashes. 691 */ 692 static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, 693 const struct in6_addr *saddr, const struct in6_addr *daddr, 694 struct udp_table *udptable, int proto) 695 { 696 struct sock *sk, *first = NULL; 697 const struct udphdr *uh = udp_hdr(skb); 698 unsigned short hnum = ntohs(uh->dest); 699 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum); 700 unsigned int offset = offsetof(typeof(*sk), sk_node); 701 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10); 702 int dif = inet6_iif(skb); 703 struct hlist_node *node; 704 struct sk_buff *nskb; 705 706 if (use_hash2) { 707 hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) & 708 udptable->mask; 709 hash2 = udp6_portaddr_hash(net, daddr, hnum) & udptable->mask; 710 start_lookup: 711 hslot = &udptable->hash2[hash2]; 712 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node); 713 } 714 715 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) { 716 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr, 717 uh->source, saddr, dif, hnum)) 718 continue; 719 /* If zero checksum and no_check is not on for 720 * the socket then skip it. 721 */ 722 if (!uh->check && !udp_sk(sk)->no_check6_rx) 723 continue; 724 if (!first) { 725 first = sk; 726 continue; 727 } 728 nskb = skb_clone(skb, GFP_ATOMIC); 729 if (unlikely(!nskb)) { 730 atomic_inc(&sk->sk_drops); 731 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS, 732 IS_UDPLITE(sk)); 733 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, 734 IS_UDPLITE(sk)); 735 continue; 736 } 737 738 if (udpv6_queue_rcv_skb(sk, nskb) > 0) 739 consume_skb(nskb); 740 } 741 742 /* Also lookup *:port if we are using hash2 and haven't done so yet. */ 743 if (use_hash2 && hash2 != hash2_any) { 744 hash2 = hash2_any; 745 goto start_lookup; 746 } 747 748 if (first) { 749 if (udpv6_queue_rcv_skb(first, skb) > 0) 750 consume_skb(skb); 751 } else { 752 kfree_skb(skb); 753 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI, 754 proto == IPPROTO_UDPLITE); 755 } 756 return 0; 757 } 758 759 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, 760 int proto) 761 { 762 const struct in6_addr *saddr, *daddr; 763 struct net *net = dev_net(skb->dev); 764 struct udphdr *uh; 765 struct sock *sk; 766 u32 ulen = 0; 767 768 if (!pskb_may_pull(skb, sizeof(struct udphdr))) 769 goto discard; 770 771 saddr = &ipv6_hdr(skb)->saddr; 772 daddr = &ipv6_hdr(skb)->daddr; 773 uh = udp_hdr(skb); 774 775 ulen = ntohs(uh->len); 776 if (ulen > skb->len) 777 goto short_packet; 778 779 if (proto == IPPROTO_UDP) { 780 /* UDP validates ulen. */ 781 782 /* Check for jumbo payload */ 783 if (ulen == 0) 784 ulen = skb->len; 785 786 if (ulen < sizeof(*uh)) 787 goto short_packet; 788 789 if (ulen < skb->len) { 790 if (pskb_trim_rcsum(skb, ulen)) 791 goto short_packet; 792 saddr = &ipv6_hdr(skb)->saddr; 793 daddr = &ipv6_hdr(skb)->daddr; 794 uh = udp_hdr(skb); 795 } 796 } 797 798 if (udp6_csum_init(skb, uh, proto)) 799 goto csum_error; 800 801 /* 802 * Multicast receive code 803 */ 804 if (ipv6_addr_is_multicast(daddr)) 805 return __udp6_lib_mcast_deliver(net, skb, 806 saddr, daddr, udptable, proto); 807 808 /* Unicast */ 809 810 /* 811 * check socket cache ... must talk to Alan about his plans 812 * for sock caches... i'll skip this for now. 813 */ 814 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable); 815 if (sk) { 816 int ret; 817 818 if (!uh->check && !udp_sk(sk)->no_check6_rx) { 819 udp6_csum_zero_error(skb); 820 goto csum_error; 821 } 822 823 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk)) 824 skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check, 825 ip6_compute_pseudo); 826 827 ret = udpv6_queue_rcv_skb(sk, skb); 828 829 /* a return value > 0 means to resubmit the input */ 830 if (ret > 0) 831 return ret; 832 833 return 0; 834 } 835 836 if (!uh->check) { 837 udp6_csum_zero_error(skb); 838 goto csum_error; 839 } 840 841 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 842 goto discard; 843 844 if (udp_lib_checksum_complete(skb)) 845 goto csum_error; 846 847 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE); 848 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 849 850 kfree_skb(skb); 851 return 0; 852 853 short_packet: 854 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n", 855 proto == IPPROTO_UDPLITE ? "-Lite" : "", 856 saddr, ntohs(uh->source), 857 ulen, skb->len, 858 daddr, ntohs(uh->dest)); 859 goto discard; 860 csum_error: 861 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE); 862 discard: 863 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); 864 kfree_skb(skb); 865 return 0; 866 } 867 868 869 static struct sock *__udp6_lib_demux_lookup(struct net *net, 870 __be16 loc_port, const struct in6_addr *loc_addr, 871 __be16 rmt_port, const struct in6_addr *rmt_addr, 872 int dif) 873 { 874 unsigned short hnum = ntohs(loc_port); 875 unsigned int hash2 = udp6_portaddr_hash(net, loc_addr, hnum); 876 unsigned int slot2 = hash2 & udp_table.mask; 877 struct udp_hslot *hslot2 = &udp_table.hash2[slot2]; 878 const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum); 879 struct sock *sk; 880 881 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { 882 if (sk->sk_state == TCP_ESTABLISHED && 883 INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif)) 884 return sk; 885 /* Only check first socket in chain */ 886 break; 887 } 888 return NULL; 889 } 890 891 static void udp_v6_early_demux(struct sk_buff *skb) 892 { 893 struct net *net = dev_net(skb->dev); 894 const struct udphdr *uh; 895 struct sock *sk; 896 struct dst_entry *dst; 897 int dif = skb->dev->ifindex; 898 899 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 900 sizeof(struct udphdr))) 901 return; 902 903 uh = udp_hdr(skb); 904 905 if (skb->pkt_type == PACKET_HOST) 906 sk = __udp6_lib_demux_lookup(net, uh->dest, 907 &ipv6_hdr(skb)->daddr, 908 uh->source, &ipv6_hdr(skb)->saddr, 909 dif); 910 else 911 return; 912 913 if (!sk || !atomic_inc_not_zero_hint(&sk->sk_refcnt, 2)) 914 return; 915 916 skb->sk = sk; 917 skb->destructor = sock_efree; 918 dst = READ_ONCE(sk->sk_rx_dst); 919 920 if (dst) 921 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); 922 if (dst) { 923 if (dst->flags & DST_NOCACHE) { 924 if (likely(atomic_inc_not_zero(&dst->__refcnt))) 925 skb_dst_set(skb, dst); 926 } else { 927 skb_dst_set_noref(skb, dst); 928 } 929 } 930 } 931 932 static __inline__ int udpv6_rcv(struct sk_buff *skb) 933 { 934 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP); 935 } 936 937 /* 938 * Throw away all pending data and cancel the corking. Socket is locked. 939 */ 940 static void udp_v6_flush_pending_frames(struct sock *sk) 941 { 942 struct udp_sock *up = udp_sk(sk); 943 944 if (up->pending == AF_INET) 945 udp_flush_pending_frames(sk); 946 else if (up->pending) { 947 up->len = 0; 948 up->pending = 0; 949 ip6_flush_pending_frames(sk); 950 } 951 } 952 953 /** 954 * udp6_hwcsum_outgoing - handle outgoing HW checksumming 955 * @sk: socket we are sending on 956 * @skb: sk_buff containing the filled-in UDP header 957 * (checksum field must be zeroed out) 958 */ 959 static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, 960 const struct in6_addr *saddr, 961 const struct in6_addr *daddr, int len) 962 { 963 unsigned int offset; 964 struct udphdr *uh = udp_hdr(skb); 965 struct sk_buff *frags = skb_shinfo(skb)->frag_list; 966 __wsum csum = 0; 967 968 if (!frags) { 969 /* Only one fragment on the socket. */ 970 skb->csum_start = skb_transport_header(skb) - skb->head; 971 skb->csum_offset = offsetof(struct udphdr, check); 972 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0); 973 } else { 974 /* 975 * HW-checksum won't work as there are two or more 976 * fragments on the socket so that all csums of sk_buffs 977 * should be together 978 */ 979 offset = skb_transport_offset(skb); 980 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); 981 982 skb->ip_summed = CHECKSUM_NONE; 983 984 do { 985 csum = csum_add(csum, frags->csum); 986 } while ((frags = frags->next)); 987 988 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 989 csum); 990 if (uh->check == 0) 991 uh->check = CSUM_MANGLED_0; 992 } 993 } 994 995 /* 996 * Sending 997 */ 998 999 static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6) 1000 { 1001 struct sock *sk = skb->sk; 1002 struct udphdr *uh; 1003 int err = 0; 1004 int is_udplite = IS_UDPLITE(sk); 1005 __wsum csum = 0; 1006 int offset = skb_transport_offset(skb); 1007 int len = skb->len - offset; 1008 1009 /* 1010 * Create a UDP header 1011 */ 1012 uh = udp_hdr(skb); 1013 uh->source = fl6->fl6_sport; 1014 uh->dest = fl6->fl6_dport; 1015 uh->len = htons(len); 1016 uh->check = 0; 1017 1018 if (is_udplite) 1019 csum = udplite_csum(skb); 1020 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */ 1021 skb->ip_summed = CHECKSUM_NONE; 1022 goto send; 1023 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ 1024 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len); 1025 goto send; 1026 } else 1027 csum = udp_csum(skb); 1028 1029 /* add protocol-dependent pseudo-header */ 1030 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr, 1031 len, fl6->flowi6_proto, csum); 1032 if (uh->check == 0) 1033 uh->check = CSUM_MANGLED_0; 1034 1035 send: 1036 err = ip6_send_skb(skb); 1037 if (err) { 1038 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) { 1039 UDP6_INC_STATS(sock_net(sk), 1040 UDP_MIB_SNDBUFERRORS, is_udplite); 1041 err = 0; 1042 } 1043 } else { 1044 UDP6_INC_STATS(sock_net(sk), 1045 UDP_MIB_OUTDATAGRAMS, is_udplite); 1046 } 1047 return err; 1048 } 1049 1050 static int udp_v6_push_pending_frames(struct sock *sk) 1051 { 1052 struct sk_buff *skb; 1053 struct udp_sock *up = udp_sk(sk); 1054 struct flowi6 fl6; 1055 int err = 0; 1056 1057 if (up->pending == AF_INET) 1058 return udp_push_pending_frames(sk); 1059 1060 /* ip6_finish_skb will release the cork, so make a copy of 1061 * fl6 here. 1062 */ 1063 fl6 = inet_sk(sk)->cork.fl.u.ip6; 1064 1065 skb = ip6_finish_skb(sk); 1066 if (!skb) 1067 goto out; 1068 1069 err = udp_v6_send_skb(skb, &fl6); 1070 1071 out: 1072 up->len = 0; 1073 up->pending = 0; 1074 return err; 1075 } 1076 1077 int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 1078 { 1079 struct ipv6_txoptions opt_space; 1080 struct udp_sock *up = udp_sk(sk); 1081 struct inet_sock *inet = inet_sk(sk); 1082 struct ipv6_pinfo *np = inet6_sk(sk); 1083 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 1084 struct in6_addr *daddr, *final_p, final; 1085 struct ipv6_txoptions *opt = NULL; 1086 struct ipv6_txoptions *opt_to_free = NULL; 1087 struct ip6_flowlabel *flowlabel = NULL; 1088 struct flowi6 fl6; 1089 struct dst_entry *dst; 1090 struct ipcm6_cookie ipc6; 1091 int addr_len = msg->msg_namelen; 1092 int ulen = len; 1093 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; 1094 int err; 1095 int connected = 0; 1096 int is_udplite = IS_UDPLITE(sk); 1097 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); 1098 struct sockcm_cookie sockc; 1099 1100 ipc6.hlimit = -1; 1101 ipc6.tclass = -1; 1102 ipc6.dontfrag = -1; 1103 sockc.tsflags = sk->sk_tsflags; 1104 1105 /* destination address check */ 1106 if (sin6) { 1107 if (addr_len < offsetof(struct sockaddr, sa_data)) 1108 return -EINVAL; 1109 1110 switch (sin6->sin6_family) { 1111 case AF_INET6: 1112 if (addr_len < SIN6_LEN_RFC2133) 1113 return -EINVAL; 1114 daddr = &sin6->sin6_addr; 1115 if (ipv6_addr_any(daddr) && 1116 ipv6_addr_v4mapped(&np->saddr)) 1117 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK), 1118 daddr); 1119 break; 1120 case AF_INET: 1121 goto do_udp_sendmsg; 1122 case AF_UNSPEC: 1123 msg->msg_name = sin6 = NULL; 1124 msg->msg_namelen = addr_len = 0; 1125 daddr = NULL; 1126 break; 1127 default: 1128 return -EINVAL; 1129 } 1130 } else if (!up->pending) { 1131 if (sk->sk_state != TCP_ESTABLISHED) 1132 return -EDESTADDRREQ; 1133 daddr = &sk->sk_v6_daddr; 1134 } else 1135 daddr = NULL; 1136 1137 if (daddr) { 1138 if (ipv6_addr_v4mapped(daddr)) { 1139 struct sockaddr_in sin; 1140 sin.sin_family = AF_INET; 1141 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport; 1142 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 1143 msg->msg_name = &sin; 1144 msg->msg_namelen = sizeof(sin); 1145 do_udp_sendmsg: 1146 if (__ipv6_only_sock(sk)) 1147 return -ENETUNREACH; 1148 return udp_sendmsg(sk, msg, len); 1149 } 1150 } 1151 1152 if (up->pending == AF_INET) 1153 return udp_sendmsg(sk, msg, len); 1154 1155 /* Rough check on arithmetic overflow, 1156 better check is made in ip6_append_data(). 1157 */ 1158 if (len > INT_MAX - sizeof(struct udphdr)) 1159 return -EMSGSIZE; 1160 1161 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; 1162 if (up->pending) { 1163 /* 1164 * There are pending frames. 1165 * The socket lock must be held while it's corked. 1166 */ 1167 lock_sock(sk); 1168 if (likely(up->pending)) { 1169 if (unlikely(up->pending != AF_INET6)) { 1170 release_sock(sk); 1171 return -EAFNOSUPPORT; 1172 } 1173 dst = NULL; 1174 goto do_append_data; 1175 } 1176 release_sock(sk); 1177 } 1178 ulen += sizeof(struct udphdr); 1179 1180 memset(&fl6, 0, sizeof(fl6)); 1181 1182 if (sin6) { 1183 if (sin6->sin6_port == 0) 1184 return -EINVAL; 1185 1186 fl6.fl6_dport = sin6->sin6_port; 1187 daddr = &sin6->sin6_addr; 1188 1189 if (np->sndflow) { 1190 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK; 1191 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 1192 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1193 if (!flowlabel) 1194 return -EINVAL; 1195 } 1196 } 1197 1198 /* 1199 * Otherwise it will be difficult to maintain 1200 * sk->sk_dst_cache. 1201 */ 1202 if (sk->sk_state == TCP_ESTABLISHED && 1203 ipv6_addr_equal(daddr, &sk->sk_v6_daddr)) 1204 daddr = &sk->sk_v6_daddr; 1205 1206 if (addr_len >= sizeof(struct sockaddr_in6) && 1207 sin6->sin6_scope_id && 1208 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr))) 1209 fl6.flowi6_oif = sin6->sin6_scope_id; 1210 } else { 1211 if (sk->sk_state != TCP_ESTABLISHED) 1212 return -EDESTADDRREQ; 1213 1214 fl6.fl6_dport = inet->inet_dport; 1215 daddr = &sk->sk_v6_daddr; 1216 fl6.flowlabel = np->flow_label; 1217 connected = 1; 1218 } 1219 1220 if (!fl6.flowi6_oif) 1221 fl6.flowi6_oif = sk->sk_bound_dev_if; 1222 1223 if (!fl6.flowi6_oif) 1224 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; 1225 1226 fl6.flowi6_mark = sk->sk_mark; 1227 fl6.flowi6_uid = sk->sk_uid; 1228 1229 if (msg->msg_controllen) { 1230 opt = &opt_space; 1231 memset(opt, 0, sizeof(struct ipv6_txoptions)); 1232 opt->tot_len = sizeof(*opt); 1233 ipc6.opt = opt; 1234 1235 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6, &sockc); 1236 if (err < 0) { 1237 fl6_sock_release(flowlabel); 1238 return err; 1239 } 1240 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) { 1241 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1242 if (!flowlabel) 1243 return -EINVAL; 1244 } 1245 if (!(opt->opt_nflen|opt->opt_flen)) 1246 opt = NULL; 1247 connected = 0; 1248 } 1249 if (!opt) { 1250 opt = txopt_get(np); 1251 opt_to_free = opt; 1252 } 1253 if (flowlabel) 1254 opt = fl6_merge_options(&opt_space, flowlabel, opt); 1255 opt = ipv6_fixup_options(&opt_space, opt); 1256 ipc6.opt = opt; 1257 1258 fl6.flowi6_proto = sk->sk_protocol; 1259 if (!ipv6_addr_any(daddr)) 1260 fl6.daddr = *daddr; 1261 else 1262 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */ 1263 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr)) 1264 fl6.saddr = np->saddr; 1265 fl6.fl6_sport = inet->inet_sport; 1266 1267 final_p = fl6_update_dst(&fl6, opt, &final); 1268 if (final_p) 1269 connected = 0; 1270 1271 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) { 1272 fl6.flowi6_oif = np->mcast_oif; 1273 connected = 0; 1274 } else if (!fl6.flowi6_oif) 1275 fl6.flowi6_oif = np->ucast_oif; 1276 1277 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); 1278 1279 if (ipc6.tclass < 0) 1280 ipc6.tclass = np->tclass; 1281 1282 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel); 1283 1284 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p); 1285 if (IS_ERR(dst)) { 1286 err = PTR_ERR(dst); 1287 dst = NULL; 1288 goto out; 1289 } 1290 1291 if (ipc6.hlimit < 0) 1292 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst); 1293 1294 if (msg->msg_flags&MSG_CONFIRM) 1295 goto do_confirm; 1296 back_from_confirm: 1297 1298 /* Lockless fast path for the non-corking case */ 1299 if (!corkreq) { 1300 struct sk_buff *skb; 1301 1302 skb = ip6_make_skb(sk, getfrag, msg, ulen, 1303 sizeof(struct udphdr), &ipc6, 1304 &fl6, (struct rt6_info *)dst, 1305 msg->msg_flags, &sockc); 1306 err = PTR_ERR(skb); 1307 if (!IS_ERR_OR_NULL(skb)) 1308 err = udp_v6_send_skb(skb, &fl6); 1309 goto release_dst; 1310 } 1311 1312 lock_sock(sk); 1313 if (unlikely(up->pending)) { 1314 /* The socket is already corked while preparing it. */ 1315 /* ... which is an evident application bug. --ANK */ 1316 release_sock(sk); 1317 1318 net_dbg_ratelimited("udp cork app bug 2\n"); 1319 err = -EINVAL; 1320 goto out; 1321 } 1322 1323 up->pending = AF_INET6; 1324 1325 do_append_data: 1326 if (ipc6.dontfrag < 0) 1327 ipc6.dontfrag = np->dontfrag; 1328 up->len += ulen; 1329 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr), 1330 &ipc6, &fl6, (struct rt6_info *)dst, 1331 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, &sockc); 1332 if (err) 1333 udp_v6_flush_pending_frames(sk); 1334 else if (!corkreq) 1335 err = udp_v6_push_pending_frames(sk); 1336 else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) 1337 up->pending = 0; 1338 1339 if (err > 0) 1340 err = np->recverr ? net_xmit_errno(err) : 0; 1341 release_sock(sk); 1342 1343 release_dst: 1344 if (dst) { 1345 if (connected) { 1346 ip6_dst_store(sk, dst, 1347 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ? 1348 &sk->sk_v6_daddr : NULL, 1349 #ifdef CONFIG_IPV6_SUBTREES 1350 ipv6_addr_equal(&fl6.saddr, &np->saddr) ? 1351 &np->saddr : 1352 #endif 1353 NULL); 1354 } else { 1355 dst_release(dst); 1356 } 1357 dst = NULL; 1358 } 1359 1360 out: 1361 dst_release(dst); 1362 fl6_sock_release(flowlabel); 1363 txopt_put(opt_to_free); 1364 if (!err) 1365 return len; 1366 /* 1367 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting 1368 * ENOBUFS might not be good (it's not tunable per se), but otherwise 1369 * we don't have a good statistic (IpOutDiscards but it can be too many 1370 * things). We could add another new stat but at least for now that 1371 * seems like overkill. 1372 */ 1373 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { 1374 UDP6_INC_STATS(sock_net(sk), 1375 UDP_MIB_SNDBUFERRORS, is_udplite); 1376 } 1377 return err; 1378 1379 do_confirm: 1380 if (msg->msg_flags & MSG_PROBE) 1381 dst_confirm_neigh(dst, &fl6.daddr); 1382 if (!(msg->msg_flags&MSG_PROBE) || len) 1383 goto back_from_confirm; 1384 err = 0; 1385 goto out; 1386 } 1387 1388 void udpv6_destroy_sock(struct sock *sk) 1389 { 1390 struct udp_sock *up = udp_sk(sk); 1391 lock_sock(sk); 1392 udp_v6_flush_pending_frames(sk); 1393 release_sock(sk); 1394 1395 if (static_key_false(&udpv6_encap_needed) && up->encap_type) { 1396 void (*encap_destroy)(struct sock *sk); 1397 encap_destroy = ACCESS_ONCE(up->encap_destroy); 1398 if (encap_destroy) 1399 encap_destroy(sk); 1400 } 1401 1402 inet6_destroy_sock(sk); 1403 } 1404 1405 /* 1406 * Socket option code for UDP 1407 */ 1408 int udpv6_setsockopt(struct sock *sk, int level, int optname, 1409 char __user *optval, unsigned int optlen) 1410 { 1411 if (level == SOL_UDP || level == SOL_UDPLITE) 1412 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1413 udp_v6_push_pending_frames); 1414 return ipv6_setsockopt(sk, level, optname, optval, optlen); 1415 } 1416 1417 #ifdef CONFIG_COMPAT 1418 int compat_udpv6_setsockopt(struct sock *sk, int level, int optname, 1419 char __user *optval, unsigned int optlen) 1420 { 1421 if (level == SOL_UDP || level == SOL_UDPLITE) 1422 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1423 udp_v6_push_pending_frames); 1424 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen); 1425 } 1426 #endif 1427 1428 int udpv6_getsockopt(struct sock *sk, int level, int optname, 1429 char __user *optval, int __user *optlen) 1430 { 1431 if (level == SOL_UDP || level == SOL_UDPLITE) 1432 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1433 return ipv6_getsockopt(sk, level, optname, optval, optlen); 1434 } 1435 1436 #ifdef CONFIG_COMPAT 1437 int compat_udpv6_getsockopt(struct sock *sk, int level, int optname, 1438 char __user *optval, int __user *optlen) 1439 { 1440 if (level == SOL_UDP || level == SOL_UDPLITE) 1441 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1442 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen); 1443 } 1444 #endif 1445 1446 static struct inet6_protocol udpv6_protocol = { 1447 .early_demux = udp_v6_early_demux, 1448 .early_demux_handler = udp_v6_early_demux, 1449 .handler = udpv6_rcv, 1450 .err_handler = udpv6_err, 1451 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1452 }; 1453 1454 /* ------------------------------------------------------------------------ */ 1455 #ifdef CONFIG_PROC_FS 1456 int udp6_seq_show(struct seq_file *seq, void *v) 1457 { 1458 if (v == SEQ_START_TOKEN) { 1459 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER); 1460 } else { 1461 int bucket = ((struct udp_iter_state *)seq->private)->bucket; 1462 struct inet_sock *inet = inet_sk(v); 1463 __u16 srcp = ntohs(inet->inet_sport); 1464 __u16 destp = ntohs(inet->inet_dport); 1465 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket); 1466 } 1467 return 0; 1468 } 1469 1470 static const struct file_operations udp6_afinfo_seq_fops = { 1471 .owner = THIS_MODULE, 1472 .open = udp_seq_open, 1473 .read = seq_read, 1474 .llseek = seq_lseek, 1475 .release = seq_release_net 1476 }; 1477 1478 static struct udp_seq_afinfo udp6_seq_afinfo = { 1479 .name = "udp6", 1480 .family = AF_INET6, 1481 .udp_table = &udp_table, 1482 .seq_fops = &udp6_afinfo_seq_fops, 1483 .seq_ops = { 1484 .show = udp6_seq_show, 1485 }, 1486 }; 1487 1488 int __net_init udp6_proc_init(struct net *net) 1489 { 1490 return udp_proc_register(net, &udp6_seq_afinfo); 1491 } 1492 1493 void udp6_proc_exit(struct net *net) 1494 { 1495 udp_proc_unregister(net, &udp6_seq_afinfo); 1496 } 1497 #endif /* CONFIG_PROC_FS */ 1498 1499 /* ------------------------------------------------------------------------ */ 1500 1501 struct proto udpv6_prot = { 1502 .name = "UDPv6", 1503 .owner = THIS_MODULE, 1504 .close = udp_lib_close, 1505 .connect = ip6_datagram_connect, 1506 .disconnect = udp_disconnect, 1507 .ioctl = udp_ioctl, 1508 .init = udp_init_sock, 1509 .destroy = udpv6_destroy_sock, 1510 .setsockopt = udpv6_setsockopt, 1511 .getsockopt = udpv6_getsockopt, 1512 .sendmsg = udpv6_sendmsg, 1513 .recvmsg = udpv6_recvmsg, 1514 .release_cb = ip6_datagram_release_cb, 1515 .hash = udp_lib_hash, 1516 .unhash = udp_lib_unhash, 1517 .rehash = udp_v6_rehash, 1518 .get_port = udp_v6_get_port, 1519 .memory_allocated = &udp_memory_allocated, 1520 .sysctl_mem = sysctl_udp_mem, 1521 .sysctl_wmem = &sysctl_udp_wmem_min, 1522 .sysctl_rmem = &sysctl_udp_rmem_min, 1523 .obj_size = sizeof(struct udp6_sock), 1524 .h.udp_table = &udp_table, 1525 #ifdef CONFIG_COMPAT 1526 .compat_setsockopt = compat_udpv6_setsockopt, 1527 .compat_getsockopt = compat_udpv6_getsockopt, 1528 #endif 1529 .diag_destroy = udp_abort, 1530 }; 1531 1532 static struct inet_protosw udpv6_protosw = { 1533 .type = SOCK_DGRAM, 1534 .protocol = IPPROTO_UDP, 1535 .prot = &udpv6_prot, 1536 .ops = &inet6_dgram_ops, 1537 .flags = INET_PROTOSW_PERMANENT, 1538 }; 1539 1540 int __init udpv6_init(void) 1541 { 1542 int ret; 1543 1544 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP); 1545 if (ret) 1546 goto out; 1547 1548 ret = inet6_register_protosw(&udpv6_protosw); 1549 if (ret) 1550 goto out_udpv6_protocol; 1551 out: 1552 return ret; 1553 1554 out_udpv6_protocol: 1555 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1556 goto out; 1557 } 1558 1559 void udpv6_exit(void) 1560 { 1561 inet6_unregister_protosw(&udpv6_protosw); 1562 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1563 } 1564