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/ndisc.h> 41 #include <net/protocol.h> 42 #include <net/transp_v6.h> 43 #include <net/ip6_route.h> 44 #include <net/raw.h> 45 #include <net/tcp_states.h> 46 #include <net/ip6_checksum.h> 47 #include <net/xfrm.h> 48 #include <net/inet6_hashtables.h> 49 #include <net/busy_poll.h> 50 51 #include <linux/proc_fs.h> 52 #include <linux/seq_file.h> 53 #include <trace/events/skb.h> 54 #include "udp_impl.h" 55 56 static u32 udp6_ehashfn(const struct net *net, 57 const struct in6_addr *laddr, 58 const u16 lport, 59 const struct in6_addr *faddr, 60 const __be16 fport) 61 { 62 static u32 udp6_ehash_secret __read_mostly; 63 static u32 udp_ipv6_hash_secret __read_mostly; 64 65 u32 lhash, fhash; 66 67 net_get_random_once(&udp6_ehash_secret, 68 sizeof(udp6_ehash_secret)); 69 net_get_random_once(&udp_ipv6_hash_secret, 70 sizeof(udp_ipv6_hash_secret)); 71 72 lhash = (__force u32)laddr->s6_addr32[3]; 73 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret); 74 75 return __inet6_ehashfn(lhash, lport, fhash, fport, 76 udp_ipv6_hash_secret + net_hash_mix(net)); 77 } 78 79 int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2) 80 { 81 const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2); 82 int sk2_ipv6only = inet_v6_ipv6only(sk2); 83 int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr); 84 int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED; 85 86 /* if both are mapped, treat as IPv4 */ 87 if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED) 88 return (!sk2_ipv6only && 89 (!sk->sk_rcv_saddr || !sk2->sk_rcv_saddr || 90 sk->sk_rcv_saddr == sk2->sk_rcv_saddr)); 91 92 if (addr_type2 == IPV6_ADDR_ANY && 93 !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED)) 94 return 1; 95 96 if (addr_type == IPV6_ADDR_ANY && 97 !(ipv6_only_sock(sk) && addr_type2 == IPV6_ADDR_MAPPED)) 98 return 1; 99 100 if (sk2_rcv_saddr6 && 101 ipv6_addr_equal(&sk->sk_v6_rcv_saddr, sk2_rcv_saddr6)) 102 return 1; 103 104 return 0; 105 } 106 107 static u32 udp6_portaddr_hash(const struct net *net, 108 const struct in6_addr *addr6, 109 unsigned int port) 110 { 111 unsigned int hash, mix = net_hash_mix(net); 112 113 if (ipv6_addr_any(addr6)) 114 hash = jhash_1word(0, mix); 115 else if (ipv6_addr_v4mapped(addr6)) 116 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix); 117 else 118 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix); 119 120 return hash ^ port; 121 } 122 123 int udp_v6_get_port(struct sock *sk, unsigned short snum) 124 { 125 unsigned int hash2_nulladdr = 126 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum); 127 unsigned int hash2_partial = 128 udp6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0); 129 130 /* precompute partial secondary hash */ 131 udp_sk(sk)->udp_portaddr_hash = hash2_partial; 132 return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr); 133 } 134 135 static void udp_v6_rehash(struct sock *sk) 136 { 137 u16 new_hash = udp6_portaddr_hash(sock_net(sk), 138 &sk->sk_v6_rcv_saddr, 139 inet_sk(sk)->inet_num); 140 141 udp_lib_rehash(sk, new_hash); 142 } 143 144 static inline int compute_score(struct sock *sk, struct net *net, 145 unsigned short hnum, 146 const struct in6_addr *saddr, __be16 sport, 147 const struct in6_addr *daddr, __be16 dport, 148 int dif) 149 { 150 int score; 151 struct inet_sock *inet; 152 153 if (!net_eq(sock_net(sk), net) || 154 udp_sk(sk)->udp_port_hash != hnum || 155 sk->sk_family != PF_INET6) 156 return -1; 157 158 score = 0; 159 inet = inet_sk(sk); 160 161 if (inet->inet_dport) { 162 if (inet->inet_dport != sport) 163 return -1; 164 score++; 165 } 166 167 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) { 168 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr)) 169 return -1; 170 score++; 171 } 172 173 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 174 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr)) 175 return -1; 176 score++; 177 } 178 179 if (sk->sk_bound_dev_if) { 180 if (sk->sk_bound_dev_if != dif) 181 return -1; 182 score++; 183 } 184 185 return score; 186 } 187 188 #define SCORE2_MAX (1 + 1 + 1) 189 static inline int compute_score2(struct sock *sk, struct net *net, 190 const struct in6_addr *saddr, __be16 sport, 191 const struct in6_addr *daddr, 192 unsigned short hnum, int dif) 193 { 194 int score; 195 struct inet_sock *inet; 196 197 if (!net_eq(sock_net(sk), net) || 198 udp_sk(sk)->udp_port_hash != hnum || 199 sk->sk_family != PF_INET6) 200 return -1; 201 202 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr)) 203 return -1; 204 205 score = 0; 206 inet = inet_sk(sk); 207 208 if (inet->inet_dport) { 209 if (inet->inet_dport != sport) 210 return -1; 211 score++; 212 } 213 214 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 215 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr)) 216 return -1; 217 score++; 218 } 219 220 if (sk->sk_bound_dev_if) { 221 if (sk->sk_bound_dev_if != dif) 222 return -1; 223 score++; 224 } 225 226 return score; 227 } 228 229 /* called with read_rcu_lock() */ 230 static struct sock *udp6_lib_lookup2(struct net *net, 231 const struct in6_addr *saddr, __be16 sport, 232 const struct in6_addr *daddr, unsigned int hnum, int dif, 233 struct udp_hslot *hslot2, unsigned int slot2) 234 { 235 struct sock *sk, *result; 236 struct hlist_nulls_node *node; 237 int score, badness, matches = 0, reuseport = 0; 238 u32 hash = 0; 239 240 begin: 241 result = NULL; 242 badness = -1; 243 udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) { 244 score = compute_score2(sk, net, saddr, sport, 245 daddr, hnum, dif); 246 if (score > badness) { 247 result = sk; 248 badness = score; 249 reuseport = sk->sk_reuseport; 250 if (reuseport) { 251 hash = udp6_ehashfn(net, daddr, hnum, 252 saddr, sport); 253 matches = 1; 254 } else if (score == SCORE2_MAX) 255 goto exact_match; 256 } else if (score == badness && reuseport) { 257 matches++; 258 if (reciprocal_scale(hash, matches) == 0) 259 result = sk; 260 hash = next_pseudo_random32(hash); 261 } 262 } 263 /* 264 * if the nulls value we got at the end of this lookup is 265 * not the expected one, we must restart lookup. 266 * We probably met an item that was moved to another chain. 267 */ 268 if (get_nulls_value(node) != slot2) 269 goto begin; 270 271 if (result) { 272 exact_match: 273 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2))) 274 result = NULL; 275 else if (unlikely(compute_score2(result, net, saddr, sport, 276 daddr, hnum, dif) < badness)) { 277 sock_put(result); 278 goto begin; 279 } 280 } 281 return result; 282 } 283 284 struct sock *__udp6_lib_lookup(struct net *net, 285 const struct in6_addr *saddr, __be16 sport, 286 const struct in6_addr *daddr, __be16 dport, 287 int dif, struct udp_table *udptable) 288 { 289 struct sock *sk, *result; 290 struct hlist_nulls_node *node; 291 unsigned short hnum = ntohs(dport); 292 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask); 293 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot]; 294 int score, badness, matches = 0, reuseport = 0; 295 u32 hash = 0; 296 297 rcu_read_lock(); 298 if (hslot->count > 10) { 299 hash2 = udp6_portaddr_hash(net, daddr, hnum); 300 slot2 = hash2 & udptable->mask; 301 hslot2 = &udptable->hash2[slot2]; 302 if (hslot->count < hslot2->count) 303 goto begin; 304 305 result = udp6_lib_lookup2(net, saddr, sport, 306 daddr, hnum, dif, 307 hslot2, slot2); 308 if (!result) { 309 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum); 310 slot2 = hash2 & udptable->mask; 311 hslot2 = &udptable->hash2[slot2]; 312 if (hslot->count < hslot2->count) 313 goto begin; 314 315 result = udp6_lib_lookup2(net, saddr, sport, 316 &in6addr_any, hnum, dif, 317 hslot2, slot2); 318 } 319 rcu_read_unlock(); 320 return result; 321 } 322 begin: 323 result = NULL; 324 badness = -1; 325 sk_nulls_for_each_rcu(sk, node, &hslot->head) { 326 score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif); 327 if (score > badness) { 328 result = sk; 329 badness = score; 330 reuseport = sk->sk_reuseport; 331 if (reuseport) { 332 hash = udp6_ehashfn(net, daddr, hnum, 333 saddr, sport); 334 matches = 1; 335 } 336 } else if (score == badness && reuseport) { 337 matches++; 338 if (reciprocal_scale(hash, matches) == 0) 339 result = sk; 340 hash = next_pseudo_random32(hash); 341 } 342 } 343 /* 344 * if the nulls value we got at the end of this lookup is 345 * not the expected one, we must restart lookup. 346 * We probably met an item that was moved to another chain. 347 */ 348 if (get_nulls_value(node) != slot) 349 goto begin; 350 351 if (result) { 352 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2))) 353 result = NULL; 354 else if (unlikely(compute_score(result, net, hnum, saddr, sport, 355 daddr, dport, dif) < badness)) { 356 sock_put(result); 357 goto begin; 358 } 359 } 360 rcu_read_unlock(); 361 return result; 362 } 363 EXPORT_SYMBOL_GPL(__udp6_lib_lookup); 364 365 static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb, 366 __be16 sport, __be16 dport, 367 struct udp_table *udptable) 368 { 369 struct sock *sk; 370 const struct ipv6hdr *iph = ipv6_hdr(skb); 371 372 sk = skb_steal_sock(skb); 373 if (unlikely(sk)) 374 return sk; 375 return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport, 376 &iph->daddr, dport, inet6_iif(skb), 377 udptable); 378 } 379 380 struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport, 381 const struct in6_addr *daddr, __be16 dport, int dif) 382 { 383 return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table); 384 } 385 EXPORT_SYMBOL_GPL(udp6_lib_lookup); 386 387 /* 388 * This should be easy, if there is something there we 389 * return it, otherwise we block. 390 */ 391 392 int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 393 int noblock, int flags, int *addr_len) 394 { 395 struct ipv6_pinfo *np = inet6_sk(sk); 396 struct inet_sock *inet = inet_sk(sk); 397 struct sk_buff *skb; 398 unsigned int ulen, copied; 399 int peeked, off = 0; 400 int err; 401 int is_udplite = IS_UDPLITE(sk); 402 int is_udp4; 403 bool slow; 404 405 if (flags & MSG_ERRQUEUE) 406 return ipv6_recv_error(sk, msg, len, addr_len); 407 408 if (np->rxpmtu && np->rxopt.bits.rxpmtu) 409 return ipv6_recv_rxpmtu(sk, msg, len, addr_len); 410 411 try_again: 412 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), 413 &peeked, &off, &err); 414 if (!skb) 415 goto out; 416 417 ulen = skb->len - sizeof(struct udphdr); 418 copied = len; 419 if (copied > ulen) 420 copied = ulen; 421 else if (copied < ulen) 422 msg->msg_flags |= MSG_TRUNC; 423 424 is_udp4 = (skb->protocol == htons(ETH_P_IP)); 425 426 /* 427 * If checksum is needed at all, try to do it while copying the 428 * data. If the data is truncated, or if we only want a partial 429 * coverage checksum (UDP-Lite), do it before the copy. 430 */ 431 432 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) { 433 if (udp_lib_checksum_complete(skb)) 434 goto csum_copy_err; 435 } 436 437 if (skb_csum_unnecessary(skb)) 438 err = skb_copy_datagram_msg(skb, sizeof(struct udphdr), 439 msg, copied); 440 else { 441 err = skb_copy_and_csum_datagram_msg(skb, sizeof(struct udphdr), msg); 442 if (err == -EINVAL) 443 goto csum_copy_err; 444 } 445 if (unlikely(err)) { 446 trace_kfree_skb(skb, udpv6_recvmsg); 447 if (!peeked) { 448 atomic_inc(&sk->sk_drops); 449 if (is_udp4) 450 UDP_INC_STATS_USER(sock_net(sk), 451 UDP_MIB_INERRORS, 452 is_udplite); 453 else 454 UDP6_INC_STATS_USER(sock_net(sk), 455 UDP_MIB_INERRORS, 456 is_udplite); 457 } 458 goto out_free; 459 } 460 if (!peeked) { 461 if (is_udp4) 462 UDP_INC_STATS_USER(sock_net(sk), 463 UDP_MIB_INDATAGRAMS, is_udplite); 464 else 465 UDP6_INC_STATS_USER(sock_net(sk), 466 UDP_MIB_INDATAGRAMS, is_udplite); 467 } 468 469 sock_recv_ts_and_drops(msg, sk, skb); 470 471 /* Copy the address. */ 472 if (msg->msg_name) { 473 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 474 sin6->sin6_family = AF_INET6; 475 sin6->sin6_port = udp_hdr(skb)->source; 476 sin6->sin6_flowinfo = 0; 477 478 if (is_udp4) { 479 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 480 &sin6->sin6_addr); 481 sin6->sin6_scope_id = 0; 482 } else { 483 sin6->sin6_addr = ipv6_hdr(skb)->saddr; 484 sin6->sin6_scope_id = 485 ipv6_iface_scope_id(&sin6->sin6_addr, 486 inet6_iif(skb)); 487 } 488 *addr_len = sizeof(*sin6); 489 } 490 491 if (np->rxopt.all) 492 ip6_datagram_recv_common_ctl(sk, msg, skb); 493 494 if (is_udp4) { 495 if (inet->cmsg_flags) 496 ip_cmsg_recv(msg, skb); 497 } else { 498 if (np->rxopt.all) 499 ip6_datagram_recv_specific_ctl(sk, msg, skb); 500 } 501 502 err = copied; 503 if (flags & MSG_TRUNC) 504 err = ulen; 505 506 out_free: 507 skb_free_datagram_locked(sk, skb); 508 out: 509 return err; 510 511 csum_copy_err: 512 slow = lock_sock_fast(sk); 513 if (!skb_kill_datagram(sk, skb, flags)) { 514 if (is_udp4) { 515 UDP_INC_STATS_USER(sock_net(sk), 516 UDP_MIB_CSUMERRORS, is_udplite); 517 UDP_INC_STATS_USER(sock_net(sk), 518 UDP_MIB_INERRORS, is_udplite); 519 } else { 520 UDP6_INC_STATS_USER(sock_net(sk), 521 UDP_MIB_CSUMERRORS, is_udplite); 522 UDP6_INC_STATS_USER(sock_net(sk), 523 UDP_MIB_INERRORS, is_udplite); 524 } 525 } 526 unlock_sock_fast(sk, slow); 527 528 if (noblock) 529 return -EAGAIN; 530 531 /* starting over for a new packet */ 532 msg->msg_flags &= ~MSG_TRUNC; 533 goto try_again; 534 } 535 536 void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 537 u8 type, u8 code, int offset, __be32 info, 538 struct udp_table *udptable) 539 { 540 struct ipv6_pinfo *np; 541 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; 542 const struct in6_addr *saddr = &hdr->saddr; 543 const struct in6_addr *daddr = &hdr->daddr; 544 struct udphdr *uh = (struct udphdr *)(skb->data+offset); 545 struct sock *sk; 546 int err; 547 struct net *net = dev_net(skb->dev); 548 549 sk = __udp6_lib_lookup(net, daddr, uh->dest, 550 saddr, uh->source, inet6_iif(skb), udptable); 551 if (!sk) { 552 ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev), 553 ICMP6_MIB_INERRORS); 554 return; 555 } 556 557 if (type == ICMPV6_PKT_TOOBIG) { 558 if (!ip6_sk_accept_pmtu(sk)) 559 goto out; 560 ip6_sk_update_pmtu(skb, sk, info); 561 } 562 if (type == NDISC_REDIRECT) { 563 ip6_sk_redirect(skb, sk); 564 goto out; 565 } 566 567 np = inet6_sk(sk); 568 569 if (!icmpv6_err_convert(type, code, &err) && !np->recverr) 570 goto out; 571 572 if (sk->sk_state != TCP_ESTABLISHED && !np->recverr) 573 goto out; 574 575 if (np->recverr) 576 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1)); 577 578 sk->sk_err = err; 579 sk->sk_error_report(sk); 580 out: 581 sock_put(sk); 582 } 583 584 static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 585 { 586 int rc; 587 588 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 589 sock_rps_save_rxhash(sk, skb); 590 sk_mark_napi_id(sk, skb); 591 sk_incoming_cpu_update(sk); 592 } 593 594 rc = sock_queue_rcv_skb(sk, skb); 595 if (rc < 0) { 596 int is_udplite = IS_UDPLITE(sk); 597 598 /* Note that an ENOMEM error is charged twice */ 599 if (rc == -ENOMEM) 600 UDP6_INC_STATS_BH(sock_net(sk), 601 UDP_MIB_RCVBUFERRORS, is_udplite); 602 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 603 kfree_skb(skb); 604 return -1; 605 } 606 return 0; 607 } 608 609 static __inline__ void udpv6_err(struct sk_buff *skb, 610 struct inet6_skb_parm *opt, u8 type, 611 u8 code, int offset, __be32 info) 612 { 613 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table); 614 } 615 616 static struct static_key udpv6_encap_needed __read_mostly; 617 void udpv6_encap_enable(void) 618 { 619 if (!static_key_enabled(&udpv6_encap_needed)) 620 static_key_slow_inc(&udpv6_encap_needed); 621 } 622 EXPORT_SYMBOL(udpv6_encap_enable); 623 624 int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 625 { 626 struct udp_sock *up = udp_sk(sk); 627 int rc; 628 int is_udplite = IS_UDPLITE(sk); 629 630 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 631 goto drop; 632 633 if (static_key_false(&udpv6_encap_needed) && up->encap_type) { 634 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); 635 636 /* 637 * This is an encapsulation socket so pass the skb to 638 * the socket's udp_encap_rcv() hook. Otherwise, just 639 * fall through and pass this up the UDP socket. 640 * up->encap_rcv() returns the following value: 641 * =0 if skb was successfully passed to the encap 642 * handler or was discarded by it. 643 * >0 if skb should be passed on to UDP. 644 * <0 if skb should be resubmitted as proto -N 645 */ 646 647 /* if we're overly short, let UDP handle it */ 648 encap_rcv = ACCESS_ONCE(up->encap_rcv); 649 if (skb->len > sizeof(struct udphdr) && encap_rcv) { 650 int ret; 651 652 /* Verify checksum before giving to encap */ 653 if (udp_lib_checksum_complete(skb)) 654 goto csum_error; 655 656 ret = encap_rcv(sk, skb); 657 if (ret <= 0) { 658 UDP_INC_STATS_BH(sock_net(sk), 659 UDP_MIB_INDATAGRAMS, 660 is_udplite); 661 return -ret; 662 } 663 } 664 665 /* FALLTHROUGH -- it's a UDP Packet */ 666 } 667 668 /* 669 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c). 670 */ 671 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { 672 673 if (up->pcrlen == 0) { /* full coverage was set */ 674 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n", 675 UDP_SKB_CB(skb)->cscov, skb->len); 676 goto drop; 677 } 678 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { 679 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n", 680 UDP_SKB_CB(skb)->cscov, up->pcrlen); 681 goto drop; 682 } 683 } 684 685 if (rcu_access_pointer(sk->sk_filter)) { 686 if (udp_lib_checksum_complete(skb)) 687 goto csum_error; 688 } 689 690 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 691 UDP6_INC_STATS_BH(sock_net(sk), 692 UDP_MIB_RCVBUFERRORS, is_udplite); 693 goto drop; 694 } 695 696 skb_dst_drop(skb); 697 698 bh_lock_sock(sk); 699 rc = 0; 700 if (!sock_owned_by_user(sk)) 701 rc = __udpv6_queue_rcv_skb(sk, skb); 702 else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 703 bh_unlock_sock(sk); 704 goto drop; 705 } 706 bh_unlock_sock(sk); 707 708 return rc; 709 710 csum_error: 711 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); 712 drop: 713 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 714 atomic_inc(&sk->sk_drops); 715 kfree_skb(skb); 716 return -1; 717 } 718 719 static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk, 720 __be16 loc_port, const struct in6_addr *loc_addr, 721 __be16 rmt_port, const struct in6_addr *rmt_addr, 722 int dif, unsigned short hnum) 723 { 724 struct inet_sock *inet = inet_sk(sk); 725 726 if (!net_eq(sock_net(sk), net)) 727 return false; 728 729 if (udp_sk(sk)->udp_port_hash != hnum || 730 sk->sk_family != PF_INET6 || 731 (inet->inet_dport && inet->inet_dport != rmt_port) || 732 (!ipv6_addr_any(&sk->sk_v6_daddr) && 733 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) || 734 (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) || 735 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) && 736 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))) 737 return false; 738 if (!inet6_mc_check(sk, loc_addr, rmt_addr)) 739 return false; 740 return true; 741 } 742 743 static void flush_stack(struct sock **stack, unsigned int count, 744 struct sk_buff *skb, unsigned int final) 745 { 746 struct sk_buff *skb1 = NULL; 747 struct sock *sk; 748 unsigned int i; 749 750 for (i = 0; i < count; i++) { 751 sk = stack[i]; 752 if (likely(!skb1)) 753 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC); 754 if (!skb1) { 755 atomic_inc(&sk->sk_drops); 756 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS, 757 IS_UDPLITE(sk)); 758 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, 759 IS_UDPLITE(sk)); 760 } 761 762 if (skb1 && udpv6_queue_rcv_skb(sk, skb1) <= 0) 763 skb1 = NULL; 764 sock_put(sk); 765 } 766 if (unlikely(skb1)) 767 kfree_skb(skb1); 768 } 769 770 static void udp6_csum_zero_error(struct sk_buff *skb) 771 { 772 /* RFC 2460 section 8.1 says that we SHOULD log 773 * this error. Well, it is reasonable. 774 */ 775 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n", 776 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source), 777 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest)); 778 } 779 780 /* 781 * Note: called only from the BH handler context, 782 * so we don't need to lock the hashes. 783 */ 784 static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, 785 const struct in6_addr *saddr, const struct in6_addr *daddr, 786 struct udp_table *udptable, int proto) 787 { 788 struct sock *sk, *stack[256 / sizeof(struct sock *)]; 789 const struct udphdr *uh = udp_hdr(skb); 790 struct hlist_nulls_node *node; 791 unsigned short hnum = ntohs(uh->dest); 792 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum); 793 int dif = inet6_iif(skb); 794 unsigned int count = 0, offset = offsetof(typeof(*sk), sk_nulls_node); 795 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10); 796 bool inner_flushed = false; 797 798 if (use_hash2) { 799 hash2_any = udp6_portaddr_hash(net, &in6addr_any, hnum) & 800 udp_table.mask; 801 hash2 = udp6_portaddr_hash(net, daddr, hnum) & udp_table.mask; 802 start_lookup: 803 hslot = &udp_table.hash2[hash2]; 804 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node); 805 } 806 807 spin_lock(&hslot->lock); 808 sk_nulls_for_each_entry_offset(sk, node, &hslot->head, offset) { 809 if (__udp_v6_is_mcast_sock(net, sk, 810 uh->dest, daddr, 811 uh->source, saddr, 812 dif, hnum) && 813 /* If zero checksum and no_check is not on for 814 * the socket then skip it. 815 */ 816 (uh->check || udp_sk(sk)->no_check6_rx)) { 817 if (unlikely(count == ARRAY_SIZE(stack))) { 818 flush_stack(stack, count, skb, ~0); 819 inner_flushed = true; 820 count = 0; 821 } 822 stack[count++] = sk; 823 sock_hold(sk); 824 } 825 } 826 827 spin_unlock(&hslot->lock); 828 829 /* Also lookup *:port if we are using hash2 and haven't done so yet. */ 830 if (use_hash2 && hash2 != hash2_any) { 831 hash2 = hash2_any; 832 goto start_lookup; 833 } 834 835 if (count) { 836 flush_stack(stack, count, skb, count - 1); 837 } else { 838 if (!inner_flushed) 839 UDP_INC_STATS_BH(net, UDP_MIB_IGNOREDMULTI, 840 proto == IPPROTO_UDPLITE); 841 consume_skb(skb); 842 } 843 return 0; 844 } 845 846 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, 847 int proto) 848 { 849 struct net *net = dev_net(skb->dev); 850 struct sock *sk; 851 struct udphdr *uh; 852 const struct in6_addr *saddr, *daddr; 853 u32 ulen = 0; 854 855 if (!pskb_may_pull(skb, sizeof(struct udphdr))) 856 goto discard; 857 858 saddr = &ipv6_hdr(skb)->saddr; 859 daddr = &ipv6_hdr(skb)->daddr; 860 uh = udp_hdr(skb); 861 862 ulen = ntohs(uh->len); 863 if (ulen > skb->len) 864 goto short_packet; 865 866 if (proto == IPPROTO_UDP) { 867 /* UDP validates ulen. */ 868 869 /* Check for jumbo payload */ 870 if (ulen == 0) 871 ulen = skb->len; 872 873 if (ulen < sizeof(*uh)) 874 goto short_packet; 875 876 if (ulen < skb->len) { 877 if (pskb_trim_rcsum(skb, ulen)) 878 goto short_packet; 879 saddr = &ipv6_hdr(skb)->saddr; 880 daddr = &ipv6_hdr(skb)->daddr; 881 uh = udp_hdr(skb); 882 } 883 } 884 885 if (udp6_csum_init(skb, uh, proto)) 886 goto csum_error; 887 888 /* 889 * Multicast receive code 890 */ 891 if (ipv6_addr_is_multicast(daddr)) 892 return __udp6_lib_mcast_deliver(net, skb, 893 saddr, daddr, udptable, proto); 894 895 /* Unicast */ 896 897 /* 898 * check socket cache ... must talk to Alan about his plans 899 * for sock caches... i'll skip this for now. 900 */ 901 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable); 902 if (sk) { 903 int ret; 904 905 if (!uh->check && !udp_sk(sk)->no_check6_rx) { 906 sock_put(sk); 907 udp6_csum_zero_error(skb); 908 goto csum_error; 909 } 910 911 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk)) 912 skb_checksum_try_convert(skb, IPPROTO_UDP, uh->check, 913 ip6_compute_pseudo); 914 915 ret = udpv6_queue_rcv_skb(sk, skb); 916 sock_put(sk); 917 918 /* a return value > 0 means to resubmit the input, but 919 * it wants the return to be -protocol, or 0 920 */ 921 if (ret > 0) 922 return -ret; 923 924 return 0; 925 } 926 927 if (!uh->check) { 928 udp6_csum_zero_error(skb); 929 goto csum_error; 930 } 931 932 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 933 goto discard; 934 935 if (udp_lib_checksum_complete(skb)) 936 goto csum_error; 937 938 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE); 939 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 940 941 kfree_skb(skb); 942 return 0; 943 944 short_packet: 945 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n", 946 proto == IPPROTO_UDPLITE ? "-Lite" : "", 947 saddr, ntohs(uh->source), 948 ulen, skb->len, 949 daddr, ntohs(uh->dest)); 950 goto discard; 951 csum_error: 952 UDP6_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE); 953 discard: 954 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); 955 kfree_skb(skb); 956 return 0; 957 } 958 959 static __inline__ int udpv6_rcv(struct sk_buff *skb) 960 { 961 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP); 962 } 963 964 /* 965 * Throw away all pending data and cancel the corking. Socket is locked. 966 */ 967 static void udp_v6_flush_pending_frames(struct sock *sk) 968 { 969 struct udp_sock *up = udp_sk(sk); 970 971 if (up->pending == AF_INET) 972 udp_flush_pending_frames(sk); 973 else if (up->pending) { 974 up->len = 0; 975 up->pending = 0; 976 ip6_flush_pending_frames(sk); 977 } 978 } 979 980 /** 981 * udp6_hwcsum_outgoing - handle outgoing HW checksumming 982 * @sk: socket we are sending on 983 * @skb: sk_buff containing the filled-in UDP header 984 * (checksum field must be zeroed out) 985 */ 986 static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, 987 const struct in6_addr *saddr, 988 const struct in6_addr *daddr, int len) 989 { 990 unsigned int offset; 991 struct udphdr *uh = udp_hdr(skb); 992 struct sk_buff *frags = skb_shinfo(skb)->frag_list; 993 __wsum csum = 0; 994 995 if (!frags) { 996 /* Only one fragment on the socket. */ 997 skb->csum_start = skb_transport_header(skb) - skb->head; 998 skb->csum_offset = offsetof(struct udphdr, check); 999 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0); 1000 } else { 1001 /* 1002 * HW-checksum won't work as there are two or more 1003 * fragments on the socket so that all csums of sk_buffs 1004 * should be together 1005 */ 1006 offset = skb_transport_offset(skb); 1007 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); 1008 1009 skb->ip_summed = CHECKSUM_NONE; 1010 1011 do { 1012 csum = csum_add(csum, frags->csum); 1013 } while ((frags = frags->next)); 1014 1015 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 1016 csum); 1017 if (uh->check == 0) 1018 uh->check = CSUM_MANGLED_0; 1019 } 1020 } 1021 1022 /* 1023 * Sending 1024 */ 1025 1026 static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6) 1027 { 1028 struct sock *sk = skb->sk; 1029 struct udphdr *uh; 1030 int err = 0; 1031 int is_udplite = IS_UDPLITE(sk); 1032 __wsum csum = 0; 1033 int offset = skb_transport_offset(skb); 1034 int len = skb->len - offset; 1035 1036 /* 1037 * Create a UDP header 1038 */ 1039 uh = udp_hdr(skb); 1040 uh->source = fl6->fl6_sport; 1041 uh->dest = fl6->fl6_dport; 1042 uh->len = htons(len); 1043 uh->check = 0; 1044 1045 if (is_udplite) 1046 csum = udplite_csum(skb); 1047 else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */ 1048 skb->ip_summed = CHECKSUM_NONE; 1049 goto send; 1050 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ 1051 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len); 1052 goto send; 1053 } else 1054 csum = udp_csum(skb); 1055 1056 /* add protocol-dependent pseudo-header */ 1057 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr, 1058 len, fl6->flowi6_proto, csum); 1059 if (uh->check == 0) 1060 uh->check = CSUM_MANGLED_0; 1061 1062 send: 1063 err = ip6_send_skb(skb); 1064 if (err) { 1065 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) { 1066 UDP6_INC_STATS_USER(sock_net(sk), 1067 UDP_MIB_SNDBUFERRORS, is_udplite); 1068 err = 0; 1069 } 1070 } else 1071 UDP6_INC_STATS_USER(sock_net(sk), 1072 UDP_MIB_OUTDATAGRAMS, is_udplite); 1073 return err; 1074 } 1075 1076 static int udp_v6_push_pending_frames(struct sock *sk) 1077 { 1078 struct sk_buff *skb; 1079 struct udp_sock *up = udp_sk(sk); 1080 struct flowi6 fl6; 1081 int err = 0; 1082 1083 if (up->pending == AF_INET) 1084 return udp_push_pending_frames(sk); 1085 1086 /* ip6_finish_skb will release the cork, so make a copy of 1087 * fl6 here. 1088 */ 1089 fl6 = inet_sk(sk)->cork.fl.u.ip6; 1090 1091 skb = ip6_finish_skb(sk); 1092 if (!skb) 1093 goto out; 1094 1095 err = udp_v6_send_skb(skb, &fl6); 1096 1097 out: 1098 up->len = 0; 1099 up->pending = 0; 1100 return err; 1101 } 1102 1103 int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 1104 { 1105 struct ipv6_txoptions opt_space; 1106 struct udp_sock *up = udp_sk(sk); 1107 struct inet_sock *inet = inet_sk(sk); 1108 struct ipv6_pinfo *np = inet6_sk(sk); 1109 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 1110 struct in6_addr *daddr, *final_p, final; 1111 struct ipv6_txoptions *opt = NULL; 1112 struct ip6_flowlabel *flowlabel = NULL; 1113 struct flowi6 fl6; 1114 struct dst_entry *dst; 1115 int addr_len = msg->msg_namelen; 1116 int ulen = len; 1117 int hlimit = -1; 1118 int tclass = -1; 1119 int dontfrag = -1; 1120 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; 1121 int err; 1122 int connected = 0; 1123 int is_udplite = IS_UDPLITE(sk); 1124 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); 1125 1126 /* destination address check */ 1127 if (sin6) { 1128 if (addr_len < offsetof(struct sockaddr, sa_data)) 1129 return -EINVAL; 1130 1131 switch (sin6->sin6_family) { 1132 case AF_INET6: 1133 if (addr_len < SIN6_LEN_RFC2133) 1134 return -EINVAL; 1135 daddr = &sin6->sin6_addr; 1136 break; 1137 case AF_INET: 1138 goto do_udp_sendmsg; 1139 case AF_UNSPEC: 1140 msg->msg_name = sin6 = NULL; 1141 msg->msg_namelen = addr_len = 0; 1142 daddr = NULL; 1143 break; 1144 default: 1145 return -EINVAL; 1146 } 1147 } else if (!up->pending) { 1148 if (sk->sk_state != TCP_ESTABLISHED) 1149 return -EDESTADDRREQ; 1150 daddr = &sk->sk_v6_daddr; 1151 } else 1152 daddr = NULL; 1153 1154 if (daddr) { 1155 if (ipv6_addr_v4mapped(daddr)) { 1156 struct sockaddr_in sin; 1157 sin.sin_family = AF_INET; 1158 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport; 1159 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 1160 msg->msg_name = &sin; 1161 msg->msg_namelen = sizeof(sin); 1162 do_udp_sendmsg: 1163 if (__ipv6_only_sock(sk)) 1164 return -ENETUNREACH; 1165 return udp_sendmsg(sk, msg, len); 1166 } 1167 } 1168 1169 if (up->pending == AF_INET) 1170 return udp_sendmsg(sk, msg, len); 1171 1172 /* Rough check on arithmetic overflow, 1173 better check is made in ip6_append_data(). 1174 */ 1175 if (len > INT_MAX - sizeof(struct udphdr)) 1176 return -EMSGSIZE; 1177 1178 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; 1179 if (up->pending) { 1180 /* 1181 * There are pending frames. 1182 * The socket lock must be held while it's corked. 1183 */ 1184 lock_sock(sk); 1185 if (likely(up->pending)) { 1186 if (unlikely(up->pending != AF_INET6)) { 1187 release_sock(sk); 1188 return -EAFNOSUPPORT; 1189 } 1190 dst = NULL; 1191 goto do_append_data; 1192 } 1193 release_sock(sk); 1194 } 1195 ulen += sizeof(struct udphdr); 1196 1197 memset(&fl6, 0, sizeof(fl6)); 1198 1199 if (sin6) { 1200 if (sin6->sin6_port == 0) 1201 return -EINVAL; 1202 1203 fl6.fl6_dport = sin6->sin6_port; 1204 daddr = &sin6->sin6_addr; 1205 1206 if (np->sndflow) { 1207 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK; 1208 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 1209 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1210 if (!flowlabel) 1211 return -EINVAL; 1212 } 1213 } 1214 1215 /* 1216 * Otherwise it will be difficult to maintain 1217 * sk->sk_dst_cache. 1218 */ 1219 if (sk->sk_state == TCP_ESTABLISHED && 1220 ipv6_addr_equal(daddr, &sk->sk_v6_daddr)) 1221 daddr = &sk->sk_v6_daddr; 1222 1223 if (addr_len >= sizeof(struct sockaddr_in6) && 1224 sin6->sin6_scope_id && 1225 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr))) 1226 fl6.flowi6_oif = sin6->sin6_scope_id; 1227 } else { 1228 if (sk->sk_state != TCP_ESTABLISHED) 1229 return -EDESTADDRREQ; 1230 1231 fl6.fl6_dport = inet->inet_dport; 1232 daddr = &sk->sk_v6_daddr; 1233 fl6.flowlabel = np->flow_label; 1234 connected = 1; 1235 } 1236 1237 if (!fl6.flowi6_oif) 1238 fl6.flowi6_oif = sk->sk_bound_dev_if; 1239 1240 if (!fl6.flowi6_oif) 1241 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; 1242 1243 fl6.flowi6_mark = sk->sk_mark; 1244 1245 if (msg->msg_controllen) { 1246 opt = &opt_space; 1247 memset(opt, 0, sizeof(struct ipv6_txoptions)); 1248 opt->tot_len = sizeof(*opt); 1249 1250 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt, 1251 &hlimit, &tclass, &dontfrag); 1252 if (err < 0) { 1253 fl6_sock_release(flowlabel); 1254 return err; 1255 } 1256 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) { 1257 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1258 if (!flowlabel) 1259 return -EINVAL; 1260 } 1261 if (!(opt->opt_nflen|opt->opt_flen)) 1262 opt = NULL; 1263 connected = 0; 1264 } 1265 if (!opt) 1266 opt = np->opt; 1267 if (flowlabel) 1268 opt = fl6_merge_options(&opt_space, flowlabel, opt); 1269 opt = ipv6_fixup_options(&opt_space, opt); 1270 1271 fl6.flowi6_proto = sk->sk_protocol; 1272 if (!ipv6_addr_any(daddr)) 1273 fl6.daddr = *daddr; 1274 else 1275 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */ 1276 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr)) 1277 fl6.saddr = np->saddr; 1278 fl6.fl6_sport = inet->inet_sport; 1279 1280 final_p = fl6_update_dst(&fl6, opt, &final); 1281 if (final_p) 1282 connected = 0; 1283 1284 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) { 1285 fl6.flowi6_oif = np->mcast_oif; 1286 connected = 0; 1287 } else if (!fl6.flowi6_oif) 1288 fl6.flowi6_oif = np->ucast_oif; 1289 1290 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); 1291 1292 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p); 1293 if (IS_ERR(dst)) { 1294 err = PTR_ERR(dst); 1295 dst = NULL; 1296 goto out; 1297 } 1298 1299 if (hlimit < 0) 1300 hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst); 1301 1302 if (tclass < 0) 1303 tclass = np->tclass; 1304 1305 if (msg->msg_flags&MSG_CONFIRM) 1306 goto do_confirm; 1307 back_from_confirm: 1308 1309 /* Lockless fast path for the non-corking case */ 1310 if (!corkreq) { 1311 struct sk_buff *skb; 1312 1313 skb = ip6_make_skb(sk, getfrag, msg, ulen, 1314 sizeof(struct udphdr), hlimit, tclass, opt, 1315 &fl6, (struct rt6_info *)dst, 1316 msg->msg_flags, dontfrag); 1317 err = PTR_ERR(skb); 1318 if (!IS_ERR_OR_NULL(skb)) 1319 err = udp_v6_send_skb(skb, &fl6); 1320 goto release_dst; 1321 } 1322 1323 lock_sock(sk); 1324 if (unlikely(up->pending)) { 1325 /* The socket is already corked while preparing it. */ 1326 /* ... which is an evident application bug. --ANK */ 1327 release_sock(sk); 1328 1329 net_dbg_ratelimited("udp cork app bug 2\n"); 1330 err = -EINVAL; 1331 goto out; 1332 } 1333 1334 up->pending = AF_INET6; 1335 1336 do_append_data: 1337 if (dontfrag < 0) 1338 dontfrag = np->dontfrag; 1339 up->len += ulen; 1340 err = ip6_append_data(sk, getfrag, msg, ulen, 1341 sizeof(struct udphdr), hlimit, tclass, opt, &fl6, 1342 (struct rt6_info *)dst, 1343 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag); 1344 if (err) 1345 udp_v6_flush_pending_frames(sk); 1346 else if (!corkreq) 1347 err = udp_v6_push_pending_frames(sk); 1348 else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) 1349 up->pending = 0; 1350 1351 if (err > 0) 1352 err = np->recverr ? net_xmit_errno(err) : 0; 1353 release_sock(sk); 1354 1355 release_dst: 1356 if (dst) { 1357 if (connected) { 1358 ip6_dst_store(sk, dst, 1359 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ? 1360 &sk->sk_v6_daddr : NULL, 1361 #ifdef CONFIG_IPV6_SUBTREES 1362 ipv6_addr_equal(&fl6.saddr, &np->saddr) ? 1363 &np->saddr : 1364 #endif 1365 NULL); 1366 } else { 1367 dst_release(dst); 1368 } 1369 dst = NULL; 1370 } 1371 1372 out: 1373 dst_release(dst); 1374 fl6_sock_release(flowlabel); 1375 if (!err) 1376 return len; 1377 /* 1378 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting 1379 * ENOBUFS might not be good (it's not tunable per se), but otherwise 1380 * we don't have a good statistic (IpOutDiscards but it can be too many 1381 * things). We could add another new stat but at least for now that 1382 * seems like overkill. 1383 */ 1384 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { 1385 UDP6_INC_STATS_USER(sock_net(sk), 1386 UDP_MIB_SNDBUFERRORS, is_udplite); 1387 } 1388 return err; 1389 1390 do_confirm: 1391 dst_confirm(dst); 1392 if (!(msg->msg_flags&MSG_PROBE) || len) 1393 goto back_from_confirm; 1394 err = 0; 1395 goto out; 1396 } 1397 1398 void udpv6_destroy_sock(struct sock *sk) 1399 { 1400 struct udp_sock *up = udp_sk(sk); 1401 lock_sock(sk); 1402 udp_v6_flush_pending_frames(sk); 1403 release_sock(sk); 1404 1405 if (static_key_false(&udpv6_encap_needed) && up->encap_type) { 1406 void (*encap_destroy)(struct sock *sk); 1407 encap_destroy = ACCESS_ONCE(up->encap_destroy); 1408 if (encap_destroy) 1409 encap_destroy(sk); 1410 } 1411 1412 inet6_destroy_sock(sk); 1413 } 1414 1415 /* 1416 * Socket option code for UDP 1417 */ 1418 int 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 ipv6_setsockopt(sk, level, optname, optval, optlen); 1425 } 1426 1427 #ifdef CONFIG_COMPAT 1428 int compat_udpv6_setsockopt(struct sock *sk, int level, int optname, 1429 char __user *optval, unsigned int optlen) 1430 { 1431 if (level == SOL_UDP || level == SOL_UDPLITE) 1432 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1433 udp_v6_push_pending_frames); 1434 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen); 1435 } 1436 #endif 1437 1438 int udpv6_getsockopt(struct sock *sk, int level, int optname, 1439 char __user *optval, int __user *optlen) 1440 { 1441 if (level == SOL_UDP || level == SOL_UDPLITE) 1442 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1443 return ipv6_getsockopt(sk, level, optname, optval, optlen); 1444 } 1445 1446 #ifdef CONFIG_COMPAT 1447 int compat_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 compat_ipv6_getsockopt(sk, level, optname, optval, optlen); 1453 } 1454 #endif 1455 1456 static const struct inet6_protocol udpv6_protocol = { 1457 .handler = udpv6_rcv, 1458 .err_handler = udpv6_err, 1459 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1460 }; 1461 1462 /* ------------------------------------------------------------------------ */ 1463 #ifdef CONFIG_PROC_FS 1464 int udp6_seq_show(struct seq_file *seq, void *v) 1465 { 1466 if (v == SEQ_START_TOKEN) { 1467 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER); 1468 } else { 1469 int bucket = ((struct udp_iter_state *)seq->private)->bucket; 1470 struct inet_sock *inet = inet_sk(v); 1471 __u16 srcp = ntohs(inet->inet_sport); 1472 __u16 destp = ntohs(inet->inet_dport); 1473 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket); 1474 } 1475 return 0; 1476 } 1477 1478 static const struct file_operations udp6_afinfo_seq_fops = { 1479 .owner = THIS_MODULE, 1480 .open = udp_seq_open, 1481 .read = seq_read, 1482 .llseek = seq_lseek, 1483 .release = seq_release_net 1484 }; 1485 1486 static struct udp_seq_afinfo udp6_seq_afinfo = { 1487 .name = "udp6", 1488 .family = AF_INET6, 1489 .udp_table = &udp_table, 1490 .seq_fops = &udp6_afinfo_seq_fops, 1491 .seq_ops = { 1492 .show = udp6_seq_show, 1493 }, 1494 }; 1495 1496 int __net_init udp6_proc_init(struct net *net) 1497 { 1498 return udp_proc_register(net, &udp6_seq_afinfo); 1499 } 1500 1501 void udp6_proc_exit(struct net *net) { 1502 udp_proc_unregister(net, &udp6_seq_afinfo); 1503 } 1504 #endif /* CONFIG_PROC_FS */ 1505 1506 void udp_v6_clear_sk(struct sock *sk, int size) 1507 { 1508 struct inet_sock *inet = inet_sk(sk); 1509 1510 /* we do not want to clear pinet6 field, because of RCU lookups */ 1511 sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6)); 1512 1513 size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6); 1514 memset(&inet->pinet6 + 1, 0, size); 1515 } 1516 1517 /* ------------------------------------------------------------------------ */ 1518 1519 struct proto udpv6_prot = { 1520 .name = "UDPv6", 1521 .owner = THIS_MODULE, 1522 .close = udp_lib_close, 1523 .connect = ip6_datagram_connect, 1524 .disconnect = udp_disconnect, 1525 .ioctl = udp_ioctl, 1526 .destroy = udpv6_destroy_sock, 1527 .setsockopt = udpv6_setsockopt, 1528 .getsockopt = udpv6_getsockopt, 1529 .sendmsg = udpv6_sendmsg, 1530 .recvmsg = udpv6_recvmsg, 1531 .backlog_rcv = __udpv6_queue_rcv_skb, 1532 .hash = udp_lib_hash, 1533 .unhash = udp_lib_unhash, 1534 .rehash = udp_v6_rehash, 1535 .get_port = udp_v6_get_port, 1536 .memory_allocated = &udp_memory_allocated, 1537 .sysctl_mem = sysctl_udp_mem, 1538 .sysctl_wmem = &sysctl_udp_wmem_min, 1539 .sysctl_rmem = &sysctl_udp_rmem_min, 1540 .obj_size = sizeof(struct udp6_sock), 1541 .slab_flags = SLAB_DESTROY_BY_RCU, 1542 .h.udp_table = &udp_table, 1543 #ifdef CONFIG_COMPAT 1544 .compat_setsockopt = compat_udpv6_setsockopt, 1545 .compat_getsockopt = compat_udpv6_getsockopt, 1546 #endif 1547 .clear_sk = udp_v6_clear_sk, 1548 }; 1549 1550 static struct inet_protosw udpv6_protosw = { 1551 .type = SOCK_DGRAM, 1552 .protocol = IPPROTO_UDP, 1553 .prot = &udpv6_prot, 1554 .ops = &inet6_dgram_ops, 1555 .flags = INET_PROTOSW_PERMANENT, 1556 }; 1557 1558 int __init udpv6_init(void) 1559 { 1560 int ret; 1561 1562 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP); 1563 if (ret) 1564 goto out; 1565 1566 ret = inet6_register_protosw(&udpv6_protosw); 1567 if (ret) 1568 goto out_udpv6_protocol; 1569 out: 1570 return ret; 1571 1572 out_udpv6_protocol: 1573 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1574 goto out; 1575 } 1576 1577 void udpv6_exit(void) 1578 { 1579 inet6_unregister_protosw(&udpv6_protosw); 1580 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1581 } 1582