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 <asm/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 u32 udp6_ehashfn(const struct net *net, 59 const struct in6_addr *laddr, 60 const u16 lport, 61 const struct in6_addr *faddr, 62 const __be16 fport) 63 { 64 static u32 udp6_ehash_secret __read_mostly; 65 static u32 udp_ipv6_hash_secret __read_mostly; 66 67 u32 lhash, fhash; 68 69 net_get_random_once(&udp6_ehash_secret, 70 sizeof(udp6_ehash_secret)); 71 net_get_random_once(&udp_ipv6_hash_secret, 72 sizeof(udp_ipv6_hash_secret)); 73 74 lhash = (__force u32)laddr->s6_addr32[3]; 75 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret); 76 77 return __inet6_ehashfn(lhash, lport, fhash, fport, 78 udp_ipv6_hash_secret + net_hash_mix(net)); 79 } 80 81 static u32 udp6_portaddr_hash(const struct net *net, 82 const struct in6_addr *addr6, 83 unsigned int port) 84 { 85 unsigned int hash, mix = net_hash_mix(net); 86 87 if (ipv6_addr_any(addr6)) 88 hash = jhash_1word(0, mix); 89 else if (ipv6_addr_v4mapped(addr6)) 90 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix); 91 else 92 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix); 93 94 return hash ^ port; 95 } 96 97 int udp_v6_get_port(struct sock *sk, unsigned short snum) 98 { 99 unsigned int hash2_nulladdr = 100 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum); 101 unsigned int hash2_partial = 102 udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0); 103 104 /* precompute partial secondary hash */ 105 udp_sk(sk)->udp_portaddr_hash = hash2_partial; 106 return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr); 107 } 108 109 static void udp_v6_rehash(struct sock *sk) 110 { 111 u16 new_hash = udp6_portaddr_hash(sock_net(sk), 112 &sk->sk_v6_rcv_saddr, 113 inet_sk(sk)->inet_num); 114 115 udp_lib_rehash(sk, new_hash); 116 } 117 118 static inline int compute_score(struct sock *sk, struct net *net, 119 unsigned short hnum, 120 const struct in6_addr *saddr, __be16 sport, 121 const struct in6_addr *daddr, __be16 dport, 122 int dif) 123 { 124 int score; 125 struct inet_sock *inet; 126 127 if (!net_eq(sock_net(sk), net) || 128 udp_sk(sk)->udp_port_hash != hnum || 129 sk->sk_family != PF_INET6) 130 return -1; 131 132 score = 0; 133 inet = inet_sk(sk); 134 135 if (inet->inet_dport) { 136 if (inet->inet_dport != sport) 137 return -1; 138 score++; 139 } 140 141 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) { 142 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr)) 143 return -1; 144 score++; 145 } 146 147 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 148 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr)) 149 return -1; 150 score++; 151 } 152 153 if (sk->sk_bound_dev_if) { 154 if (sk->sk_bound_dev_if != dif) 155 return -1; 156 score++; 157 } 158 159 if (sk->sk_incoming_cpu == raw_smp_processor_id()) 160 score++; 161 162 return score; 163 } 164 165 static inline int compute_score2(struct sock *sk, struct net *net, 166 const struct in6_addr *saddr, __be16 sport, 167 const struct in6_addr *daddr, 168 unsigned short hnum, int dif) 169 { 170 int score; 171 struct inet_sock *inet; 172 173 if (!net_eq(sock_net(sk), net) || 174 udp_sk(sk)->udp_port_hash != hnum || 175 sk->sk_family != PF_INET6) 176 return -1; 177 178 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr)) 179 return -1; 180 181 score = 0; 182 inet = inet_sk(sk); 183 184 if (inet->inet_dport) { 185 if (inet->inet_dport != sport) 186 return -1; 187 score++; 188 } 189 190 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 191 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr)) 192 return -1; 193 score++; 194 } 195 196 if (sk->sk_bound_dev_if) { 197 if (sk->sk_bound_dev_if != dif) 198 return -1; 199 score++; 200 } 201 202 if (sk->sk_incoming_cpu == raw_smp_processor_id()) 203 score++; 204 205 return score; 206 } 207 208 /* called with read_rcu_lock() */ 209 static struct sock *udp6_lib_lookup2(struct net *net, 210 const struct in6_addr *saddr, __be16 sport, 211 const struct in6_addr *daddr, unsigned int hnum, int dif, 212 struct udp_hslot *hslot2, unsigned int slot2, 213 struct sk_buff *skb) 214 { 215 struct sock *sk, *result; 216 struct hlist_nulls_node *node; 217 int score, badness, matches = 0, reuseport = 0; 218 bool select_ok = true; 219 u32 hash = 0; 220 221 begin: 222 result = NULL; 223 badness = -1; 224 udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) { 225 score = compute_score2(sk, net, saddr, sport, 226 daddr, hnum, dif); 227 if (score > badness) { 228 result = sk; 229 badness = score; 230 reuseport = sk->sk_reuseport; 231 if (reuseport) { 232 hash = udp6_ehashfn(net, daddr, hnum, 233 saddr, sport); 234 if (select_ok) { 235 struct sock *sk2; 236 237 sk2 = reuseport_select_sock(sk, hash, skb, 238 sizeof(struct udphdr)); 239 if (sk2) { 240 result = sk2; 241 select_ok = false; 242 goto found; 243 } 244 } 245 matches = 1; 246 } 247 } else if (score == badness && reuseport) { 248 matches++; 249 if (reciprocal_scale(hash, matches) == 0) 250 result = sk; 251 hash = next_pseudo_random32(hash); 252 } 253 } 254 /* 255 * if the nulls value we got at the end of this lookup is 256 * not the expected one, we must restart lookup. 257 * We probably met an item that was moved to another chain. 258 */ 259 if (get_nulls_value(node) != slot2) 260 goto begin; 261 262 if (result) { 263 found: 264 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2))) 265 result = NULL; 266 else if (unlikely(compute_score2(result, net, saddr, sport, 267 daddr, hnum, dif) < badness)) { 268 sock_put(result); 269 goto begin; 270 } 271 } 272 return result; 273 } 274 275 struct sock *__udp6_lib_lookup(struct net *net, 276 const struct in6_addr *saddr, __be16 sport, 277 const struct in6_addr *daddr, __be16 dport, 278 int dif, struct udp_table *udptable, 279 struct sk_buff *skb) 280 { 281 struct sock *sk, *result; 282 struct hlist_nulls_node *node; 283 unsigned short hnum = ntohs(dport); 284 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask); 285 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot]; 286 int score, badness, matches = 0, reuseport = 0; 287 bool select_ok = true; 288 u32 hash = 0; 289 290 rcu_read_lock(); 291 if (hslot->count > 10) { 292 hash2 = udp6_portaddr_hash(net, daddr, hnum); 293 slot2 = hash2 & udptable->mask; 294 hslot2 = &udptable->hash2[slot2]; 295 if (hslot->count < hslot2->count) 296 goto begin; 297 298 result = udp6_lib_lookup2(net, saddr, sport, 299 daddr, hnum, dif, 300 hslot2, slot2, skb); 301 if (!result) { 302 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum); 303 slot2 = hash2 & udptable->mask; 304 hslot2 = &udptable->hash2[slot2]; 305 if (hslot->count < hslot2->count) 306 goto begin; 307 308 result = udp6_lib_lookup2(net, saddr, sport, 309 &in6addr_any, hnum, dif, 310 hslot2, slot2, skb); 311 } 312 rcu_read_unlock(); 313 return result; 314 } 315 begin: 316 result = NULL; 317 badness = -1; 318 sk_nulls_for_each_rcu(sk, node, &hslot->head) { 319 score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif); 320 if (score > badness) { 321 result = sk; 322 badness = score; 323 reuseport = sk->sk_reuseport; 324 if (reuseport) { 325 hash = udp6_ehashfn(net, daddr, hnum, 326 saddr, sport); 327 if (select_ok) { 328 struct sock *sk2; 329 330 sk2 = reuseport_select_sock(sk, hash, skb, 331 sizeof(struct udphdr)); 332 if (sk2) { 333 result = sk2; 334 select_ok = false; 335 goto found; 336 } 337 } 338 matches = 1; 339 } 340 } else if (score == badness && reuseport) { 341 matches++; 342 if (reciprocal_scale(hash, matches) == 0) 343 result = sk; 344 hash = next_pseudo_random32(hash); 345 } 346 } 347 /* 348 * if the nulls value we got at the end of this lookup is 349 * not the expected one, we must restart lookup. 350 * We probably met an item that was moved to another chain. 351 */ 352 if (get_nulls_value(node) != slot) 353 goto begin; 354 355 if (result) { 356 found: 357 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2))) 358 result = NULL; 359 else if (unlikely(compute_score(result, net, hnum, saddr, sport, 360 daddr, dport, dif) < badness)) { 361 sock_put(result); 362 goto begin; 363 } 364 } 365 rcu_read_unlock(); 366 return result; 367 } 368 EXPORT_SYMBOL_GPL(__udp6_lib_lookup); 369 370 static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb, 371 __be16 sport, __be16 dport, 372 struct udp_table *udptable) 373 { 374 struct sock *sk; 375 const struct ipv6hdr *iph = ipv6_hdr(skb); 376 377 sk = skb_steal_sock(skb); 378 if (unlikely(sk)) 379 return sk; 380 return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport, 381 &iph->daddr, dport, inet6_iif(skb), 382 udptable, skb); 383 } 384 385 struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport, 386 const struct in6_addr *daddr, __be16 dport, int dif) 387 { 388 return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table, NULL); 389 } 390 EXPORT_SYMBOL_GPL(udp6_lib_lookup); 391 392 /* 393 * This should be easy, if there is something there we 394 * return it, otherwise we block. 395 */ 396 397 int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 398 int noblock, int flags, int *addr_len) 399 { 400 struct ipv6_pinfo *np = inet6_sk(sk); 401 struct inet_sock *inet = inet_sk(sk); 402 struct sk_buff *skb; 403 unsigned int ulen, copied; 404 int peeked, off = 0; 405 int err; 406 int is_udplite = IS_UDPLITE(sk); 407 bool checksum_valid = false; 408 int is_udp4; 409 bool slow; 410 411 if (flags & MSG_ERRQUEUE) 412 return ipv6_recv_error(sk, msg, len, addr_len); 413 414 if (np->rxpmtu && np->rxopt.bits.rxpmtu) 415 return ipv6_recv_rxpmtu(sk, msg, len, addr_len); 416 417 try_again: 418 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), 419 &peeked, &off, &err); 420 if (!skb) 421 goto out; 422 423 ulen = skb->len - sizeof(struct udphdr); 424 copied = len; 425 if (copied > ulen) 426 copied = ulen; 427 else if (copied < ulen) 428 msg->msg_flags |= MSG_TRUNC; 429 430 is_udp4 = (skb->protocol == htons(ETH_P_IP)); 431 432 /* 433 * If checksum is needed at all, try to do it while copying the 434 * data. If the data is truncated, or if we only want a partial 435 * coverage checksum (UDP-Lite), do it before the copy. 436 */ 437 438 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) { 439 checksum_valid = !udp_lib_checksum_complete(skb); 440 if (!checksum_valid) 441 goto csum_copy_err; 442 } 443 444 if (checksum_valid || skb_csum_unnecessary(skb)) 445 err = skb_copy_datagram_msg(skb, sizeof(struct udphdr), 446 msg, copied); 447 else { 448 err = skb_copy_and_csum_datagram_msg(skb, sizeof(struct udphdr), msg); 449 if (err == -EINVAL) 450 goto csum_copy_err; 451 } 452 if (unlikely(err)) { 453 trace_kfree_skb(skb, udpv6_recvmsg); 454 if (!peeked) { 455 atomic_inc(&sk->sk_drops); 456 if (is_udp4) 457 UDP_INC_STATS_USER(sock_net(sk), 458 UDP_MIB_INERRORS, 459 is_udplite); 460 else 461 UDP6_INC_STATS_USER(sock_net(sk), 462 UDP_MIB_INERRORS, 463 is_udplite); 464 } 465 goto out_free; 466 } 467 if (!peeked) { 468 if (is_udp4) 469 UDP_INC_STATS_USER(sock_net(sk), 470 UDP_MIB_INDATAGRAMS, is_udplite); 471 else 472 UDP6_INC_STATS_USER(sock_net(sk), 473 UDP_MIB_INDATAGRAMS, is_udplite); 474 } 475 476 sock_recv_ts_and_drops(msg, sk, skb); 477 478 /* Copy the address. */ 479 if (msg->msg_name) { 480 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 481 sin6->sin6_family = AF_INET6; 482 sin6->sin6_port = udp_hdr(skb)->source; 483 sin6->sin6_flowinfo = 0; 484 485 if (is_udp4) { 486 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 487 &sin6->sin6_addr); 488 sin6->sin6_scope_id = 0; 489 } else { 490 sin6->sin6_addr = ipv6_hdr(skb)->saddr; 491 sin6->sin6_scope_id = 492 ipv6_iface_scope_id(&sin6->sin6_addr, 493 inet6_iif(skb)); 494 } 495 *addr_len = sizeof(*sin6); 496 } 497 498 if (np->rxopt.all) 499 ip6_datagram_recv_common_ctl(sk, msg, skb); 500 501 if (is_udp4) { 502 if (inet->cmsg_flags) 503 ip_cmsg_recv(msg, skb); 504 } else { 505 if (np->rxopt.all) 506 ip6_datagram_recv_specific_ctl(sk, msg, skb); 507 } 508 509 err = copied; 510 if (flags & MSG_TRUNC) 511 err = ulen; 512 513 out_free: 514 skb_free_datagram_locked(sk, skb); 515 out: 516 return err; 517 518 csum_copy_err: 519 slow = lock_sock_fast(sk); 520 if (!skb_kill_datagram(sk, skb, flags)) { 521 if (is_udp4) { 522 UDP_INC_STATS_USER(sock_net(sk), 523 UDP_MIB_CSUMERRORS, is_udplite); 524 UDP_INC_STATS_USER(sock_net(sk), 525 UDP_MIB_INERRORS, is_udplite); 526 } else { 527 UDP6_INC_STATS_USER(sock_net(sk), 528 UDP_MIB_CSUMERRORS, is_udplite); 529 UDP6_INC_STATS_USER(sock_net(sk), 530 UDP_MIB_INERRORS, is_udplite); 531 } 532 } 533 unlock_sock_fast(sk, slow); 534 535 /* starting over for a new packet, but check if we need to yield */ 536 cond_resched(); 537 msg->msg_flags &= ~MSG_TRUNC; 538 goto try_again; 539 } 540 541 void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 542 u8 type, u8 code, int offset, __be32 info, 543 struct udp_table *udptable) 544 { 545 struct ipv6_pinfo *np; 546 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; 547 const struct in6_addr *saddr = &hdr->saddr; 548 const struct in6_addr *daddr = &hdr->daddr; 549 struct udphdr *uh = (struct udphdr *)(skb->data+offset); 550 struct sock *sk; 551 int harderr; 552 int err; 553 struct net *net = dev_net(skb->dev); 554 555 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source, 556 inet6_iif(skb), udptable, skb); 557 if (!sk) { 558 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), 559 ICMP6_MIB_INERRORS); 560 return; 561 } 562 563 harderr = icmpv6_err_convert(type, code, &err); 564 np = inet6_sk(sk); 565 566 if (type == ICMPV6_PKT_TOOBIG) { 567 if (!ip6_sk_accept_pmtu(sk)) 568 goto out; 569 ip6_sk_update_pmtu(skb, sk, info); 570 if (np->pmtudisc != IPV6_PMTUDISC_DONT) 571 harderr = 1; 572 } 573 if (type == NDISC_REDIRECT) { 574 ip6_sk_redirect(skb, sk); 575 goto out; 576 } 577 578 if (!np->recverr) { 579 if (!harderr || sk->sk_state != TCP_ESTABLISHED) 580 goto out; 581 } else { 582 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1)); 583 } 584 585 sk->sk_err = err; 586 sk->sk_error_report(sk); 587 out: 588 sock_put(sk); 589 } 590 591 static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 592 { 593 int rc; 594 595 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 596 sock_rps_save_rxhash(sk, skb); 597 sk_mark_napi_id(sk, skb); 598 sk_incoming_cpu_update(sk); 599 } 600 601 rc = sock_queue_rcv_skb(sk, skb); 602 if (rc < 0) { 603 int is_udplite = IS_UDPLITE(sk); 604 605 /* Note that an ENOMEM error is charged twice */ 606 if (rc == -ENOMEM) 607 UDP6_INC_STATS_BH(sock_net(sk), 608 UDP_MIB_RCVBUFERRORS, is_udplite); 609 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 610 kfree_skb(skb); 611 return -1; 612 } 613 return 0; 614 } 615 616 static __inline__ void udpv6_err(struct sk_buff *skb, 617 struct inet6_skb_parm *opt, u8 type, 618 u8 code, int offset, __be32 info) 619 { 620 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table); 621 } 622 623 static struct static_key udpv6_encap_needed __read_mostly; 624 void udpv6_encap_enable(void) 625 { 626 if (!static_key_enabled(&udpv6_encap_needed)) 627 static_key_slow_inc(&udpv6_encap_needed); 628 } 629 EXPORT_SYMBOL(udpv6_encap_enable); 630 631 int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 632 { 633 struct udp_sock *up = udp_sk(sk); 634 int rc; 635 int is_udplite = IS_UDPLITE(sk); 636 637 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 638 goto drop; 639 640 if (static_key_false(&udpv6_encap_needed) && up->encap_type) { 641 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); 642 643 /* 644 * This is an encapsulation socket so pass the skb to 645 * the socket's udp_encap_rcv() hook. Otherwise, just 646 * fall through and pass this up the UDP socket. 647 * up->encap_rcv() returns the following value: 648 * =0 if skb was successfully passed to the encap 649 * handler or was discarded by it. 650 * >0 if skb should be passed on to UDP. 651 * <0 if skb should be resubmitted as proto -N 652 */ 653 654 /* if we're overly short, let UDP handle it */ 655 encap_rcv = ACCESS_ONCE(up->encap_rcv); 656 if (skb->len > sizeof(struct udphdr) && encap_rcv) { 657 int ret; 658 659 /* Verify checksum before giving to encap */ 660 if (udp_lib_checksum_complete(skb)) 661 goto csum_error; 662 663 ret = encap_rcv(sk, skb); 664 if (ret <= 0) { 665 UDP_INC_STATS_BH(sock_net(sk), 666 UDP_MIB_INDATAGRAMS, 667 is_udplite); 668 return -ret; 669 } 670 } 671 672 /* FALLTHROUGH -- it's a UDP Packet */ 673 } 674 675 /* 676 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c). 677 */ 678 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { 679 680 if (up->pcrlen == 0) { /* full coverage was set */ 681 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n", 682 UDP_SKB_CB(skb)->cscov, skb->len); 683 goto drop; 684 } 685 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { 686 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n", 687 UDP_SKB_CB(skb)->cscov, up->pcrlen); 688 goto drop; 689 } 690 } 691 692 if (rcu_access_pointer(sk->sk_filter)) { 693 if (udp_lib_checksum_complete(skb)) 694 goto csum_error; 695 } 696 697 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 698 UDP6_INC_STATS_BH(sock_net(sk), 699 UDP_MIB_RCVBUFERRORS, is_udplite); 700 goto drop; 701 } 702 703 skb_dst_drop(skb); 704 705 bh_lock_sock(sk); 706 rc = 0; 707 if (!sock_owned_by_user(sk)) 708 rc = __udpv6_queue_rcv_skb(sk, skb); 709 else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 710 bh_unlock_sock(sk); 711 goto drop; 712 } 713 bh_unlock_sock(sk); 714 715 return rc; 716 717 csum_error: 718 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); 719 drop: 720 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 721 atomic_inc(&sk->sk_drops); 722 kfree_skb(skb); 723 return -1; 724 } 725 726 static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk, 727 __be16 loc_port, const struct in6_addr *loc_addr, 728 __be16 rmt_port, const struct in6_addr *rmt_addr, 729 int dif, unsigned short hnum) 730 { 731 struct inet_sock *inet = inet_sk(sk); 732 733 if (!net_eq(sock_net(sk), net)) 734 return false; 735 736 if (udp_sk(sk)->udp_port_hash != hnum || 737 sk->sk_family != PF_INET6 || 738 (inet->inet_dport && inet->inet_dport != rmt_port) || 739 (!ipv6_addr_any(&sk->sk_v6_daddr) && 740 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) || 741 (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) || 742 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) && 743 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))) 744 return false; 745 if (!inet6_mc_check(sk, loc_addr, rmt_addr)) 746 return false; 747 return true; 748 } 749 750 static void flush_stack(struct sock **stack, unsigned int count, 751 struct sk_buff *skb, unsigned int final) 752 { 753 struct sk_buff *skb1 = NULL; 754 struct sock *sk; 755 unsigned int i; 756 757 for (i = 0; i < count; i++) { 758 sk = stack[i]; 759 if (likely(!skb1)) 760 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC); 761 if (!skb1) { 762 atomic_inc(&sk->sk_drops); 763 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS, 764 IS_UDPLITE(sk)); 765 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, 766 IS_UDPLITE(sk)); 767 } 768 769 if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0) 770 skb1 = NULL; 771 sock_put(sk); 772 } 773 if (unlikely(skb1)) 774 kfree_skb(skb1); 775 } 776 777 static void udp6_csum_zero_error(struct sk_buff *skb) 778 { 779 /* RFC 2460 section 8.1 says that we SHOULD log 780 * this error. Well, it is reasonable. 781 */ 782 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n", 783 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source), 784 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest)); 785 } 786 787 /* 788 * Note: called only from the BH handler context, 789 * so we don't need to lock the hashes. 790 */ 791 static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, 792 const struct in6_addr *saddr, const struct in6_addr *daddr, 793 struct udp_table *udptable, int proto) 794 { 795 struct sock *sk, *stack[256 / sizeof(struct sock *)]; 796 const struct udphdr *uh = udp_hdr(skb); 797 struct hlist_nulls_node *node; 798 unsigned short hnum = ntohs(uh->dest); 799 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum); 800 int dif = inet6_iif(skb); 801 unsigned int count = 0, offset = offsetof(typeof(*sk), sk_nulls_node); 802 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10); 803 bool inner_flushed = false; 804 805 if (use_hash2) { 806 hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) & 807 udp_table.mask; 808 hash2 = udp6_portaddr_hash(net, daddr, hnum) & udp_table.mask; 809 start_lookup: 810 hslot = &udp_table.hash2[hash2]; 811 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node); 812 } 813 814 spin_lock(&hslot->lock); 815 sk_nulls_for_each_entry_offset(sk, node, &hslot->head, offset) { 816 if (__udp_v6_is_mcast_sock(net, sk, 817 uh->dest, daddr, 818 uh->source, saddr, 819 dif, hnum) && 820 /* If zero checksum and no_check is not on for 821 * the socket then skip it. 822 */ 823 (uh->check || udp_sk(sk)->no_check6_rx)) { 824 if (unlikely(count == ARRAY_SIZE(stack))) { 825 flush_stack(stack, count, skb, ~0); 826 inner_flushed = true; 827 count = 0; 828 } 829 stack[count++] = sk; 830 sock_hold(sk); 831 } 832 } 833 834 spin_unlock(&hslot->lock); 835 836 /* Also lookup *:port if we are using hash2 and haven't done so yet. */ 837 if (use_hash2 && hash2 != hash2_any) { 838 hash2 = hash2_any; 839 goto start_lookup; 840 } 841 842 if (count) { 843 flush_stack(stack, count, skb, count - 1); 844 } else { 845 if (!inner_flushed) 846 UDP6_INC_STATS_BH(net, UDP_MIB_IGNOREDMULTI, 847 proto == IPPROTO_UDPLITE); 848 consume_skb(skb); 849 } 850 return 0; 851 } 852 853 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, 854 int proto) 855 { 856 struct net *net = dev_net(skb->dev); 857 struct sock *sk; 858 struct udphdr *uh; 859 const struct in6_addr *saddr, *daddr; 860 u32 ulen = 0; 861 862 if (!pskb_may_pull(skb, sizeof(struct udphdr))) 863 goto discard; 864 865 saddr = &ipv6_hdr(skb)->saddr; 866 daddr = &ipv6_hdr(skb)->daddr; 867 uh = udp_hdr(skb); 868 869 ulen = ntohs(uh->len); 870 if (ulen > skb->len) 871 goto short_packet; 872 873 if (proto == IPPROTO_UDP) { 874 /* UDP validates ulen. */ 875 876 /* Check for jumbo payload */ 877 if (ulen == 0) 878 ulen = skb->len; 879 880 if (ulen < sizeof(*uh)) 881 goto short_packet; 882 883 if (ulen < skb->len) { 884 if (pskb_trim_rcsum(skb, ulen)) 885 goto short_packet; 886 saddr = &ipv6_hdr(skb)->saddr; 887 daddr = &ipv6_hdr(skb)->daddr; 888 uh = udp_hdr(skb); 889 } 890 } 891 892 if (udp6_csum_init(skb, uh, proto)) 893 goto csum_error; 894 895 /* 896 * Multicast receive code 897 */ 898 if (ipv6_addr_is_multicast(daddr)) 899 return __udp6_lib_mcast_deliver(net, skb, 900 saddr, daddr, udptable, proto); 901 902 /* Unicast */ 903 904 /* 905 * check socket cache ... must talk to Alan about his plans 906 * for sock caches... i'll skip this for now. 907 */ 908 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable); 909 if (sk) { 910 int ret; 911 912 if (!uh->check && !udp_sk(sk)->no_check6_rx) { 913 sock_put(sk); 914 udp6_csum_zero_error(skb); 915 goto csum_error; 916 } 917 918 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk)) 919 skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check, 920 ip6_compute_pseudo); 921 922 ret = udpv6_queue_rcv_skb(sk, skb); 923 sock_put(sk); 924 925 /* a return value > 0 means to resubmit the input */ 926 if (ret > 0) 927 return ret; 928 929 return 0; 930 } 931 932 if (!uh->check) { 933 udp6_csum_zero_error(skb); 934 goto csum_error; 935 } 936 937 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 938 goto discard; 939 940 if (udp_lib_checksum_complete(skb)) 941 goto csum_error; 942 943 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE); 944 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 945 946 kfree_skb(skb); 947 return 0; 948 949 short_packet: 950 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n", 951 proto == IPPROTO_UDPLITE ? "-Lite" : "", 952 saddr, ntohs(uh->source), 953 ulen, skb->len, 954 daddr, ntohs(uh->dest)); 955 goto discard; 956 csum_error: 957 UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE); 958 discard: 959 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); 960 kfree_skb(skb); 961 return 0; 962 } 963 964 static __inline__ int udpv6_rcv(struct sk_buff *skb) 965 { 966 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP); 967 } 968 969 /* 970 * Throw away all pending data and cancel the corking. Socket is locked. 971 */ 972 static void udp_v6_flush_pending_frames(struct sock *sk) 973 { 974 struct udp_sock *up = udp_sk(sk); 975 976 if (up->pending == AF_INET) 977 udp_flush_pending_frames(sk); 978 else if (up->pending) { 979 up->len = 0; 980 up->pending = 0; 981 ip6_flush_pending_frames(sk); 982 } 983 } 984 985 /** 986 * udp6_hwcsum_outgoing - handle outgoing HW checksumming 987 * @sk: socket we are sending on 988 * @skb: sk_buff containing the filled-in UDP header 989 * (checksum field must be zeroed out) 990 */ 991 static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, 992 const struct in6_addr *saddr, 993 const struct in6_addr *daddr, int len) 994 { 995 unsigned int offset; 996 struct udphdr *uh = udp_hdr(skb); 997 struct sk_buff *frags = skb_shinfo(skb)->frag_list; 998 __wsum csum = 0; 999 1000 if (!frags) { 1001 /* Only one fragment on the socket. */ 1002 skb->csum_start = skb_transport_header(skb) - skb->head; 1003 skb->csum_offset = offsetof(struct udphdr, check); 1004 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0); 1005 } else { 1006 /* 1007 * HW-checksum won't work as there are two or more 1008 * fragments on the socket so that all csums of sk_buffs 1009 * should be together 1010 */ 1011 offset = skb_transport_offset(skb); 1012 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); 1013 1014 skb->ip_summed = CHECKSUM_NONE; 1015 1016 do { 1017 csum = csum_add(csum, frags->csum); 1018 } while ((frags = frags->next)); 1019 1020 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 1021 csum); 1022 if (uh->check == 0) 1023 uh->check = CSUM_MANGLED_0; 1024 } 1025 } 1026 1027 /* 1028 * Sending 1029 */ 1030 1031 static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6) 1032 { 1033 struct sock *sk = skb->sk; 1034 struct udphdr *uh; 1035 int err = 0; 1036 int is_udplite = IS_UDPLITE(sk); 1037 __wsum csum = 0; 1038 int offset = skb_transport_offset(skb); 1039 int len = skb->len - offset; 1040 1041 /* 1042 * Create a UDP header 1043 */ 1044 uh = udp_hdr(skb); 1045 uh->source = fl6->fl6_sport; 1046 uh->dest = fl6->fl6_dport; 1047 uh->len = htons(len); 1048 uh->check = 0; 1049 1050 if (is_udplite) 1051 csum = udplite_csum(skb); 1052 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */ 1053 skb->ip_summed = CHECKSUM_NONE; 1054 goto send; 1055 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ 1056 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len); 1057 goto send; 1058 } else 1059 csum = udp_csum(skb); 1060 1061 /* add protocol-dependent pseudo-header */ 1062 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr, 1063 len, fl6->flowi6_proto, csum); 1064 if (uh->check == 0) 1065 uh->check = CSUM_MANGLED_0; 1066 1067 send: 1068 err = ip6_send_skb(skb); 1069 if (err) { 1070 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) { 1071 UDP6_INC_STATS_USER(sock_net(sk), 1072 UDP_MIB_SNDBUFERRORS, is_udplite); 1073 err = 0; 1074 } 1075 } else 1076 UDP6_INC_STATS_USER(sock_net(sk), 1077 UDP_MIB_OUTDATAGRAMS, is_udplite); 1078 return err; 1079 } 1080 1081 static int udp_v6_push_pending_frames(struct sock *sk) 1082 { 1083 struct sk_buff *skb; 1084 struct udp_sock *up = udp_sk(sk); 1085 struct flowi6 fl6; 1086 int err = 0; 1087 1088 if (up->pending == AF_INET) 1089 return udp_push_pending_frames(sk); 1090 1091 /* ip6_finish_skb will release the cork, so make a copy of 1092 * fl6 here. 1093 */ 1094 fl6 = inet_sk(sk)->cork.fl.u.ip6; 1095 1096 skb = ip6_finish_skb(sk); 1097 if (!skb) 1098 goto out; 1099 1100 err = udp_v6_send_skb(skb, &fl6); 1101 1102 out: 1103 up->len = 0; 1104 up->pending = 0; 1105 return err; 1106 } 1107 1108 int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 1109 { 1110 struct ipv6_txoptions opt_space; 1111 struct udp_sock *up = udp_sk(sk); 1112 struct inet_sock *inet = inet_sk(sk); 1113 struct ipv6_pinfo *np = inet6_sk(sk); 1114 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 1115 struct in6_addr *daddr, *final_p, final; 1116 struct ipv6_txoptions *opt = NULL; 1117 struct ipv6_txoptions *opt_to_free = NULL; 1118 struct ip6_flowlabel *flowlabel = NULL; 1119 struct flowi6 fl6; 1120 struct dst_entry *dst; 1121 int addr_len = msg->msg_namelen; 1122 int ulen = len; 1123 int hlimit = -1; 1124 int tclass = -1; 1125 int dontfrag = -1; 1126 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; 1127 int err; 1128 int connected = 0; 1129 int is_udplite = IS_UDPLITE(sk); 1130 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); 1131 1132 /* destination address check */ 1133 if (sin6) { 1134 if (addr_len < offsetof(struct sockaddr, sa_data)) 1135 return -EINVAL; 1136 1137 switch (sin6->sin6_family) { 1138 case AF_INET6: 1139 if (addr_len < SIN6_LEN_RFC2133) 1140 return -EINVAL; 1141 daddr = &sin6->sin6_addr; 1142 break; 1143 case AF_INET: 1144 goto do_udp_sendmsg; 1145 case AF_UNSPEC: 1146 msg->msg_name = sin6 = NULL; 1147 msg->msg_namelen = addr_len = 0; 1148 daddr = NULL; 1149 break; 1150 default: 1151 return -EINVAL; 1152 } 1153 } else if (!up->pending) { 1154 if (sk->sk_state != TCP_ESTABLISHED) 1155 return -EDESTADDRREQ; 1156 daddr = &sk->sk_v6_daddr; 1157 } else 1158 daddr = NULL; 1159 1160 if (daddr) { 1161 if (ipv6_addr_v4mapped(daddr)) { 1162 struct sockaddr_in sin; 1163 sin.sin_family = AF_INET; 1164 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport; 1165 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 1166 msg->msg_name = &sin; 1167 msg->msg_namelen = sizeof(sin); 1168 do_udp_sendmsg: 1169 if (__ipv6_only_sock(sk)) 1170 return -ENETUNREACH; 1171 return udp_sendmsg(sk, msg, len); 1172 } 1173 } 1174 1175 if (up->pending == AF_INET) 1176 return udp_sendmsg(sk, msg, len); 1177 1178 /* Rough check on arithmetic overflow, 1179 better check is made in ip6_append_data(). 1180 */ 1181 if (len > INT_MAX - sizeof(struct udphdr)) 1182 return -EMSGSIZE; 1183 1184 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; 1185 if (up->pending) { 1186 /* 1187 * There are pending frames. 1188 * The socket lock must be held while it's corked. 1189 */ 1190 lock_sock(sk); 1191 if (likely(up->pending)) { 1192 if (unlikely(up->pending != AF_INET6)) { 1193 release_sock(sk); 1194 return -EAFNOSUPPORT; 1195 } 1196 dst = NULL; 1197 goto do_append_data; 1198 } 1199 release_sock(sk); 1200 } 1201 ulen += sizeof(struct udphdr); 1202 1203 memset(&fl6, 0, sizeof(fl6)); 1204 1205 if (sin6) { 1206 if (sin6->sin6_port == 0) 1207 return -EINVAL; 1208 1209 fl6.fl6_dport = sin6->sin6_port; 1210 daddr = &sin6->sin6_addr; 1211 1212 if (np->sndflow) { 1213 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK; 1214 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 1215 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1216 if (!flowlabel) 1217 return -EINVAL; 1218 } 1219 } 1220 1221 /* 1222 * Otherwise it will be difficult to maintain 1223 * sk->sk_dst_cache. 1224 */ 1225 if (sk->sk_state == TCP_ESTABLISHED && 1226 ipv6_addr_equal(daddr, &sk->sk_v6_daddr)) 1227 daddr = &sk->sk_v6_daddr; 1228 1229 if (addr_len >= sizeof(struct sockaddr_in6) && 1230 sin6->sin6_scope_id && 1231 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr))) 1232 fl6.flowi6_oif = sin6->sin6_scope_id; 1233 } else { 1234 if (sk->sk_state != TCP_ESTABLISHED) 1235 return -EDESTADDRREQ; 1236 1237 fl6.fl6_dport = inet->inet_dport; 1238 daddr = &sk->sk_v6_daddr; 1239 fl6.flowlabel = np->flow_label; 1240 connected = 1; 1241 } 1242 1243 if (!fl6.flowi6_oif) 1244 fl6.flowi6_oif = sk->sk_bound_dev_if; 1245 1246 if (!fl6.flowi6_oif) 1247 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; 1248 1249 fl6.flowi6_mark = sk->sk_mark; 1250 1251 if (msg->msg_controllen) { 1252 opt = &opt_space; 1253 memset(opt, 0, sizeof(struct ipv6_txoptions)); 1254 opt->tot_len = sizeof(*opt); 1255 1256 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt, 1257 &hlimit, &tclass, &dontfrag); 1258 if (err < 0) { 1259 fl6_sock_release(flowlabel); 1260 return err; 1261 } 1262 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) { 1263 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1264 if (!flowlabel) 1265 return -EINVAL; 1266 } 1267 if (!(opt->opt_nflen|opt->opt_flen)) 1268 opt = NULL; 1269 connected = 0; 1270 } 1271 if (!opt) { 1272 opt = txopt_get(np); 1273 opt_to_free = opt; 1274 } 1275 if (flowlabel) 1276 opt = fl6_merge_options(&opt_space, flowlabel, opt); 1277 opt = ipv6_fixup_options(&opt_space, opt); 1278 1279 fl6.flowi6_proto = sk->sk_protocol; 1280 if (!ipv6_addr_any(daddr)) 1281 fl6.daddr = *daddr; 1282 else 1283 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */ 1284 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr)) 1285 fl6.saddr = np->saddr; 1286 fl6.fl6_sport = inet->inet_sport; 1287 1288 final_p = fl6_update_dst(&fl6, opt, &final); 1289 if (final_p) 1290 connected = 0; 1291 1292 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) { 1293 fl6.flowi6_oif = np->mcast_oif; 1294 connected = 0; 1295 } else if (!fl6.flowi6_oif) 1296 fl6.flowi6_oif = np->ucast_oif; 1297 1298 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); 1299 1300 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p); 1301 if (IS_ERR(dst)) { 1302 err = PTR_ERR(dst); 1303 dst = NULL; 1304 goto out; 1305 } 1306 1307 if (hlimit < 0) 1308 hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst); 1309 1310 if (tclass < 0) 1311 tclass = np->tclass; 1312 1313 if (msg->msg_flags&MSG_CONFIRM) 1314 goto do_confirm; 1315 back_from_confirm: 1316 1317 /* Lockless fast path for the non-corking case */ 1318 if (!corkreq) { 1319 struct sk_buff *skb; 1320 1321 skb = ip6_make_skb(sk, getfrag, msg, ulen, 1322 sizeof(struct udphdr), hlimit, tclass, opt, 1323 &fl6, (struct rt6_info *)dst, 1324 msg->msg_flags, dontfrag); 1325 err = PTR_ERR(skb); 1326 if (!IS_ERR_OR_NULL(skb)) 1327 err = udp_v6_send_skb(skb, &fl6); 1328 goto release_dst; 1329 } 1330 1331 lock_sock(sk); 1332 if (unlikely(up->pending)) { 1333 /* The socket is already corked while preparing it. */ 1334 /* ... which is an evident application bug. --ANK */ 1335 release_sock(sk); 1336 1337 net_dbg_ratelimited("udp cork app bug 2\n"); 1338 err = -EINVAL; 1339 goto out; 1340 } 1341 1342 up->pending = AF_INET6; 1343 1344 do_append_data: 1345 if (dontfrag < 0) 1346 dontfrag = np->dontfrag; 1347 up->len += ulen; 1348 err = ip6_append_data(sk, getfrag, msg, ulen, 1349 sizeof(struct udphdr), hlimit, tclass, opt, &fl6, 1350 (struct rt6_info *)dst, 1351 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag); 1352 if (err) 1353 udp_v6_flush_pending_frames(sk); 1354 else if (!corkreq) 1355 err = udp_v6_push_pending_frames(sk); 1356 else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) 1357 up->pending = 0; 1358 1359 if (err > 0) 1360 err = np->recverr ? net_xmit_errno(err) : 0; 1361 release_sock(sk); 1362 1363 release_dst: 1364 if (dst) { 1365 if (connected) { 1366 ip6_dst_store(sk, dst, 1367 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ? 1368 &sk->sk_v6_daddr : NULL, 1369 #ifdef CONFIG_IPV6_SUBTREES 1370 ipv6_addr_equal(&fl6.saddr, &np->saddr) ? 1371 &np->saddr : 1372 #endif 1373 NULL); 1374 } else { 1375 dst_release(dst); 1376 } 1377 dst = NULL; 1378 } 1379 1380 out: 1381 dst_release(dst); 1382 fl6_sock_release(flowlabel); 1383 txopt_put(opt_to_free); 1384 if (!err) 1385 return len; 1386 /* 1387 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting 1388 * ENOBUFS might not be good (it's not tunable per se), but otherwise 1389 * we don't have a good statistic (IpOutDiscards but it can be too many 1390 * things). We could add another new stat but at least for now that 1391 * seems like overkill. 1392 */ 1393 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { 1394 UDP6_INC_STATS_USER(sock_net(sk), 1395 UDP_MIB_SNDBUFERRORS, is_udplite); 1396 } 1397 return err; 1398 1399 do_confirm: 1400 dst_confirm(dst); 1401 if (!(msg->msg_flags&MSG_PROBE) || len) 1402 goto back_from_confirm; 1403 err = 0; 1404 goto out; 1405 } 1406 1407 void udpv6_destroy_sock(struct sock *sk) 1408 { 1409 struct udp_sock *up = udp_sk(sk); 1410 lock_sock(sk); 1411 udp_v6_flush_pending_frames(sk); 1412 release_sock(sk); 1413 1414 if (static_key_false(&udpv6_encap_needed) && up->encap_type) { 1415 void (*encap_destroy)(struct sock *sk); 1416 encap_destroy = ACCESS_ONCE(up->encap_destroy); 1417 if (encap_destroy) 1418 encap_destroy(sk); 1419 } 1420 1421 inet6_destroy_sock(sk); 1422 } 1423 1424 /* 1425 * Socket option code for UDP 1426 */ 1427 int udpv6_setsockopt(struct sock *sk, int level, int optname, 1428 char __user *optval, unsigned int optlen) 1429 { 1430 if (level == SOL_UDP || level == SOL_UDPLITE) 1431 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1432 udp_v6_push_pending_frames); 1433 return ipv6_setsockopt(sk, level, optname, optval, optlen); 1434 } 1435 1436 #ifdef CONFIG_COMPAT 1437 int compat_udpv6_setsockopt(struct sock *sk, int level, int optname, 1438 char __user *optval, unsigned int optlen) 1439 { 1440 if (level == SOL_UDP || level == SOL_UDPLITE) 1441 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1442 udp_v6_push_pending_frames); 1443 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen); 1444 } 1445 #endif 1446 1447 int udpv6_getsockopt(struct sock *sk, int level, int optname, 1448 char __user *optval, int __user *optlen) 1449 { 1450 if (level == SOL_UDP || level == SOL_UDPLITE) 1451 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1452 return ipv6_getsockopt(sk, level, optname, optval, optlen); 1453 } 1454 1455 #ifdef CONFIG_COMPAT 1456 int compat_udpv6_getsockopt(struct sock *sk, int level, int optname, 1457 char __user *optval, int __user *optlen) 1458 { 1459 if (level == SOL_UDP || level == SOL_UDPLITE) 1460 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1461 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen); 1462 } 1463 #endif 1464 1465 static const struct inet6_protocol udpv6_protocol = { 1466 .handler = udpv6_rcv, 1467 .err_handler = udpv6_err, 1468 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1469 }; 1470 1471 /* ------------------------------------------------------------------------ */ 1472 #ifdef CONFIG_PROC_FS 1473 int udp6_seq_show(struct seq_file *seq, void *v) 1474 { 1475 if (v == SEQ_START_TOKEN) { 1476 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER); 1477 } else { 1478 int bucket = ((struct udp_iter_state *)seq->private)->bucket; 1479 struct inet_sock *inet = inet_sk(v); 1480 __u16 srcp = ntohs(inet->inet_sport); 1481 __u16 destp = ntohs(inet->inet_dport); 1482 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket); 1483 } 1484 return 0; 1485 } 1486 1487 static const struct file_operations udp6_afinfo_seq_fops = { 1488 .owner = THIS_MODULE, 1489 .open = udp_seq_open, 1490 .read = seq_read, 1491 .llseek = seq_lseek, 1492 .release = seq_release_net 1493 }; 1494 1495 static struct udp_seq_afinfo udp6_seq_afinfo = { 1496 .name = "udp6", 1497 .family = AF_INET6, 1498 .udp_table = &udp_table, 1499 .seq_fops = &udp6_afinfo_seq_fops, 1500 .seq_ops = { 1501 .show = udp6_seq_show, 1502 }, 1503 }; 1504 1505 int __net_init udp6_proc_init(struct net *net) 1506 { 1507 return udp_proc_register(net, &udp6_seq_afinfo); 1508 } 1509 1510 void udp6_proc_exit(struct net *net) 1511 { 1512 udp_proc_unregister(net, &udp6_seq_afinfo); 1513 } 1514 #endif /* CONFIG_PROC_FS */ 1515 1516 void udp_v6_clear_sk(struct sock *sk, int size) 1517 { 1518 struct inet_sock *inet = inet_sk(sk); 1519 1520 /* we do not want to clear pinet6 field, because of RCU lookups */ 1521 sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6)); 1522 1523 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6); 1524 memset(&inet->pinet6 + 1, 0, size); 1525 } 1526 1527 /* ------------------------------------------------------------------------ */ 1528 1529 struct proto udpv6_prot = { 1530 .name = "UDPv6", 1531 .owner = THIS_MODULE, 1532 .close = udp_lib_close, 1533 .connect = ip6_datagram_connect, 1534 .disconnect = udp_disconnect, 1535 .ioctl = udp_ioctl, 1536 .destroy = udpv6_destroy_sock, 1537 .setsockopt = udpv6_setsockopt, 1538 .getsockopt = udpv6_getsockopt, 1539 .sendmsg = udpv6_sendmsg, 1540 .recvmsg = udpv6_recvmsg, 1541 .backlog_rcv = __udpv6_queue_rcv_skb, 1542 .release_cb = ip6_datagram_release_cb, 1543 .hash = udp_lib_hash, 1544 .unhash = udp_lib_unhash, 1545 .rehash = udp_v6_rehash, 1546 .get_port = udp_v6_get_port, 1547 .memory_allocated = &udp_memory_allocated, 1548 .sysctl_mem = sysctl_udp_mem, 1549 .sysctl_wmem = &sysctl_udp_wmem_min, 1550 .sysctl_rmem = &sysctl_udp_rmem_min, 1551 .obj_size = sizeof(struct udp6_sock), 1552 .slab_flags = SLAB_DESTROY_BY_RCU, 1553 .h.udp_table = &udp_table, 1554 #ifdef CONFIG_COMPAT 1555 .compat_setsockopt = compat_udpv6_setsockopt, 1556 .compat_getsockopt = compat_udpv6_getsockopt, 1557 #endif 1558 .clear_sk = udp_v6_clear_sk, 1559 }; 1560 1561 static struct inet_protosw udpv6_protosw = { 1562 .type = SOCK_DGRAM, 1563 .protocol = IPPROTO_UDP, 1564 .prot = &udpv6_prot, 1565 .ops = &inet6_dgram_ops, 1566 .flags = INET_PROTOSW_PERMANENT, 1567 }; 1568 1569 int __init udpv6_init(void) 1570 { 1571 int ret; 1572 1573 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP); 1574 if (ret) 1575 goto out; 1576 1577 ret = inet6_register_protosw(&udpv6_protosw); 1578 if (ret) 1579 goto out_udpv6_protocol; 1580 out: 1581 return ret; 1582 1583 out_udpv6_protocol: 1584 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1585 goto out; 1586 } 1587 1588 void udpv6_exit(void) 1589 { 1590 inet6_unregister_protosw(&udpv6_protosw); 1591 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1592 } 1593