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 <asm/uaccess.h> 38 39 #include <net/ndisc.h> 40 #include <net/protocol.h> 41 #include <net/transp_v6.h> 42 #include <net/ip6_route.h> 43 #include <net/raw.h> 44 #include <net/tcp_states.h> 45 #include <net/ip6_checksum.h> 46 #include <net/xfrm.h> 47 48 #include <linux/proc_fs.h> 49 #include <linux/seq_file.h> 50 #include "udp_impl.h" 51 52 int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2) 53 { 54 const struct in6_addr *sk_rcv_saddr6 = &inet6_sk(sk)->rcv_saddr; 55 const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2); 56 __be32 sk_rcv_saddr = inet_sk(sk)->rcv_saddr; 57 __be32 sk2_rcv_saddr = inet_rcv_saddr(sk2); 58 int sk_ipv6only = ipv6_only_sock(sk); 59 int sk2_ipv6only = inet_v6_ipv6only(sk2); 60 int addr_type = ipv6_addr_type(sk_rcv_saddr6); 61 int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED; 62 63 /* if both are mapped, treat as IPv4 */ 64 if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED) 65 return (!sk2_ipv6only && 66 (!sk_rcv_saddr || !sk2_rcv_saddr || 67 sk_rcv_saddr == sk2_rcv_saddr)); 68 69 if (addr_type2 == IPV6_ADDR_ANY && 70 !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED)) 71 return 1; 72 73 if (addr_type == IPV6_ADDR_ANY && 74 !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED)) 75 return 1; 76 77 if (sk2_rcv_saddr6 && 78 ipv6_addr_equal(sk_rcv_saddr6, sk2_rcv_saddr6)) 79 return 1; 80 81 return 0; 82 } 83 84 int udp_v6_get_port(struct sock *sk, unsigned short snum) 85 { 86 return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal); 87 } 88 89 static inline int compute_score(struct sock *sk, struct net *net, 90 unsigned short hnum, 91 struct in6_addr *saddr, __be16 sport, 92 struct in6_addr *daddr, __be16 dport, 93 int dif) 94 { 95 int score = -1; 96 97 if (net_eq(sock_net(sk), net) && sk->sk_hash == hnum && 98 sk->sk_family == PF_INET6) { 99 struct ipv6_pinfo *np = inet6_sk(sk); 100 struct inet_sock *inet = inet_sk(sk); 101 102 score = 0; 103 if (inet->dport) { 104 if (inet->dport != sport) 105 return -1; 106 score++; 107 } 108 if (!ipv6_addr_any(&np->rcv_saddr)) { 109 if (!ipv6_addr_equal(&np->rcv_saddr, daddr)) 110 return -1; 111 score++; 112 } 113 if (!ipv6_addr_any(&np->daddr)) { 114 if (!ipv6_addr_equal(&np->daddr, saddr)) 115 return -1; 116 score++; 117 } 118 if (sk->sk_bound_dev_if) { 119 if (sk->sk_bound_dev_if != dif) 120 return -1; 121 score++; 122 } 123 } 124 return score; 125 } 126 127 static struct sock *__udp6_lib_lookup(struct net *net, 128 struct in6_addr *saddr, __be16 sport, 129 struct in6_addr *daddr, __be16 dport, 130 int dif, struct udp_table *udptable) 131 { 132 struct sock *sk, *result; 133 struct hlist_nulls_node *node; 134 unsigned short hnum = ntohs(dport); 135 unsigned int hash = udp_hashfn(net, hnum); 136 struct udp_hslot *hslot = &udptable->hash[hash]; 137 int score, badness; 138 139 rcu_read_lock(); 140 begin: 141 result = NULL; 142 badness = -1; 143 sk_nulls_for_each_rcu(sk, node, &hslot->head) { 144 score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif); 145 if (score > badness) { 146 result = sk; 147 badness = score; 148 } 149 } 150 /* 151 * if the nulls value we got at the end of this lookup is 152 * not the expected one, we must restart lookup. 153 * We probably met an item that was moved to another chain. 154 */ 155 if (get_nulls_value(node) != hash) 156 goto begin; 157 158 if (result) { 159 if (unlikely(!atomic_inc_not_zero(&result->sk_refcnt))) 160 result = NULL; 161 else if (unlikely(compute_score(result, net, hnum, saddr, sport, 162 daddr, dport, dif) < badness)) { 163 sock_put(result); 164 goto begin; 165 } 166 } 167 rcu_read_unlock(); 168 return result; 169 } 170 171 static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb, 172 __be16 sport, __be16 dport, 173 struct udp_table *udptable) 174 { 175 struct sock *sk; 176 struct ipv6hdr *iph = ipv6_hdr(skb); 177 178 if (unlikely(sk = skb_steal_sock(skb))) 179 return sk; 180 return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport, 181 &iph->daddr, dport, inet6_iif(skb), 182 udptable); 183 } 184 185 /* 186 * This should be easy, if there is something there we 187 * return it, otherwise we block. 188 */ 189 190 int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk, 191 struct msghdr *msg, size_t len, 192 int noblock, int flags, int *addr_len) 193 { 194 struct ipv6_pinfo *np = inet6_sk(sk); 195 struct inet_sock *inet = inet_sk(sk); 196 struct sk_buff *skb; 197 unsigned int ulen, copied; 198 int peeked; 199 int err; 200 int is_udplite = IS_UDPLITE(sk); 201 int is_udp4; 202 203 if (addr_len) 204 *addr_len=sizeof(struct sockaddr_in6); 205 206 if (flags & MSG_ERRQUEUE) 207 return ipv6_recv_error(sk, msg, len); 208 209 try_again: 210 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), 211 &peeked, &err); 212 if (!skb) 213 goto out; 214 215 ulen = skb->len - sizeof(struct udphdr); 216 copied = len; 217 if (copied > ulen) 218 copied = ulen; 219 else if (copied < ulen) 220 msg->msg_flags |= MSG_TRUNC; 221 222 is_udp4 = (skb->protocol == htons(ETH_P_IP)); 223 224 /* 225 * If checksum is needed at all, try to do it while copying the 226 * data. If the data is truncated, or if we only want a partial 227 * coverage checksum (UDP-Lite), do it before the copy. 228 */ 229 230 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) { 231 if (udp_lib_checksum_complete(skb)) 232 goto csum_copy_err; 233 } 234 235 if (skb_csum_unnecessary(skb)) 236 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), 237 msg->msg_iov, copied ); 238 else { 239 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov); 240 if (err == -EINVAL) 241 goto csum_copy_err; 242 } 243 if (err) 244 goto out_free; 245 246 if (!peeked) { 247 if (is_udp4) 248 UDP_INC_STATS_USER(sock_net(sk), 249 UDP_MIB_INDATAGRAMS, is_udplite); 250 else 251 UDP6_INC_STATS_USER(sock_net(sk), 252 UDP_MIB_INDATAGRAMS, is_udplite); 253 } 254 255 sock_recv_timestamp(msg, sk, skb); 256 257 /* Copy the address. */ 258 if (msg->msg_name) { 259 struct sockaddr_in6 *sin6; 260 261 sin6 = (struct sockaddr_in6 *) msg->msg_name; 262 sin6->sin6_family = AF_INET6; 263 sin6->sin6_port = udp_hdr(skb)->source; 264 sin6->sin6_flowinfo = 0; 265 sin6->sin6_scope_id = 0; 266 267 if (is_udp4) 268 ipv6_addr_set(&sin6->sin6_addr, 0, 0, 269 htonl(0xffff), ip_hdr(skb)->saddr); 270 else { 271 ipv6_addr_copy(&sin6->sin6_addr, 272 &ipv6_hdr(skb)->saddr); 273 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) 274 sin6->sin6_scope_id = IP6CB(skb)->iif; 275 } 276 277 } 278 if (is_udp4) { 279 if (inet->cmsg_flags) 280 ip_cmsg_recv(msg, skb); 281 } else { 282 if (np->rxopt.all) 283 datagram_recv_ctl(sk, msg, skb); 284 } 285 286 err = copied; 287 if (flags & MSG_TRUNC) 288 err = ulen; 289 290 out_free: 291 lock_sock(sk); 292 skb_free_datagram(sk, skb); 293 release_sock(sk); 294 out: 295 return err; 296 297 csum_copy_err: 298 lock_sock(sk); 299 if (!skb_kill_datagram(sk, skb, flags)) { 300 if (is_udp4) 301 UDP_INC_STATS_USER(sock_net(sk), 302 UDP_MIB_INERRORS, is_udplite); 303 else 304 UDP6_INC_STATS_USER(sock_net(sk), 305 UDP_MIB_INERRORS, is_udplite); 306 } 307 release_sock(sk); 308 309 if (flags & MSG_DONTWAIT) 310 return -EAGAIN; 311 goto try_again; 312 } 313 314 void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 315 u8 type, u8 code, int offset, __be32 info, 316 struct udp_table *udptable) 317 { 318 struct ipv6_pinfo *np; 319 struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data; 320 struct in6_addr *saddr = &hdr->saddr; 321 struct in6_addr *daddr = &hdr->daddr; 322 struct udphdr *uh = (struct udphdr*)(skb->data+offset); 323 struct sock *sk; 324 int err; 325 326 sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest, 327 saddr, uh->source, inet6_iif(skb), udptable); 328 if (sk == NULL) 329 return; 330 331 np = inet6_sk(sk); 332 333 if (!icmpv6_err_convert(type, code, &err) && !np->recverr) 334 goto out; 335 336 if (sk->sk_state != TCP_ESTABLISHED && !np->recverr) 337 goto out; 338 339 if (np->recverr) 340 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1)); 341 342 sk->sk_err = err; 343 sk->sk_error_report(sk); 344 out: 345 sock_put(sk); 346 } 347 348 static __inline__ void udpv6_err(struct sk_buff *skb, 349 struct inet6_skb_parm *opt, u8 type, 350 u8 code, int offset, __be32 info ) 351 { 352 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table); 353 } 354 355 int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) 356 { 357 struct udp_sock *up = udp_sk(sk); 358 int rc; 359 int is_udplite = IS_UDPLITE(sk); 360 361 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 362 goto drop; 363 364 /* 365 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c). 366 */ 367 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { 368 369 if (up->pcrlen == 0) { /* full coverage was set */ 370 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage" 371 " %d while full coverage %d requested\n", 372 UDP_SKB_CB(skb)->cscov, skb->len); 373 goto drop; 374 } 375 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { 376 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d " 377 "too small, need min %d\n", 378 UDP_SKB_CB(skb)->cscov, up->pcrlen); 379 goto drop; 380 } 381 } 382 383 if (sk->sk_filter) { 384 if (udp_lib_checksum_complete(skb)) 385 goto drop; 386 } 387 388 if ((rc = sock_queue_rcv_skb(sk,skb)) < 0) { 389 /* Note that an ENOMEM error is charged twice */ 390 if (rc == -ENOMEM) { 391 UDP6_INC_STATS_BH(sock_net(sk), 392 UDP_MIB_RCVBUFERRORS, is_udplite); 393 atomic_inc(&sk->sk_drops); 394 } 395 goto drop; 396 } 397 398 return 0; 399 drop: 400 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 401 kfree_skb(skb); 402 return -1; 403 } 404 405 static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk, 406 __be16 loc_port, struct in6_addr *loc_addr, 407 __be16 rmt_port, struct in6_addr *rmt_addr, 408 int dif) 409 { 410 struct hlist_nulls_node *node; 411 struct sock *s = sk; 412 unsigned short num = ntohs(loc_port); 413 414 sk_nulls_for_each_from(s, node) { 415 struct inet_sock *inet = inet_sk(s); 416 417 if (!net_eq(sock_net(s), net)) 418 continue; 419 420 if (s->sk_hash == num && s->sk_family == PF_INET6) { 421 struct ipv6_pinfo *np = inet6_sk(s); 422 if (inet->dport) { 423 if (inet->dport != rmt_port) 424 continue; 425 } 426 if (!ipv6_addr_any(&np->daddr) && 427 !ipv6_addr_equal(&np->daddr, rmt_addr)) 428 continue; 429 430 if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif) 431 continue; 432 433 if (!ipv6_addr_any(&np->rcv_saddr)) { 434 if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr)) 435 continue; 436 } 437 if (!inet6_mc_check(s, loc_addr, rmt_addr)) 438 continue; 439 return s; 440 } 441 } 442 return NULL; 443 } 444 445 /* 446 * Note: called only from the BH handler context, 447 * so we don't need to lock the hashes. 448 */ 449 static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, 450 struct in6_addr *saddr, struct in6_addr *daddr, 451 struct udp_table *udptable) 452 { 453 struct sock *sk, *sk2; 454 const struct udphdr *uh = udp_hdr(skb); 455 struct udp_hslot *hslot = &udptable->hash[udp_hashfn(net, ntohs(uh->dest))]; 456 int dif; 457 458 spin_lock(&hslot->lock); 459 sk = sk_nulls_head(&hslot->head); 460 dif = inet6_iif(skb); 461 sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif); 462 if (!sk) { 463 kfree_skb(skb); 464 goto out; 465 } 466 467 sk2 = sk; 468 while ((sk2 = udp_v6_mcast_next(net, sk_nulls_next(sk2), uh->dest, daddr, 469 uh->source, saddr, dif))) { 470 struct sk_buff *buff = skb_clone(skb, GFP_ATOMIC); 471 if (buff) { 472 bh_lock_sock(sk2); 473 if (!sock_owned_by_user(sk2)) 474 udpv6_queue_rcv_skb(sk2, buff); 475 else 476 sk_add_backlog(sk2, buff); 477 bh_unlock_sock(sk2); 478 } 479 } 480 bh_lock_sock(sk); 481 if (!sock_owned_by_user(sk)) 482 udpv6_queue_rcv_skb(sk, skb); 483 else 484 sk_add_backlog(sk, skb); 485 bh_unlock_sock(sk); 486 out: 487 spin_unlock(&hslot->lock); 488 return 0; 489 } 490 491 static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, 492 int proto) 493 { 494 int err; 495 496 UDP_SKB_CB(skb)->partial_cov = 0; 497 UDP_SKB_CB(skb)->cscov = skb->len; 498 499 if (proto == IPPROTO_UDPLITE) { 500 err = udplite_checksum_init(skb, uh); 501 if (err) 502 return err; 503 } 504 505 if (uh->check == 0) { 506 /* RFC 2460 section 8.1 says that we SHOULD log 507 this error. Well, it is reasonable. 508 */ 509 LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n"); 510 return 1; 511 } 512 if (skb->ip_summed == CHECKSUM_COMPLETE && 513 !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr, 514 skb->len, proto, skb->csum)) 515 skb->ip_summed = CHECKSUM_UNNECESSARY; 516 517 if (!skb_csum_unnecessary(skb)) 518 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr, 519 &ipv6_hdr(skb)->daddr, 520 skb->len, proto, 0)); 521 522 return 0; 523 } 524 525 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, 526 int proto) 527 { 528 struct sock *sk; 529 struct udphdr *uh; 530 struct net_device *dev = skb->dev; 531 struct in6_addr *saddr, *daddr; 532 u32 ulen = 0; 533 struct net *net = dev_net(skb->dev); 534 535 if (!pskb_may_pull(skb, sizeof(struct udphdr))) 536 goto short_packet; 537 538 saddr = &ipv6_hdr(skb)->saddr; 539 daddr = &ipv6_hdr(skb)->daddr; 540 uh = udp_hdr(skb); 541 542 ulen = ntohs(uh->len); 543 if (ulen > skb->len) 544 goto short_packet; 545 546 if (proto == IPPROTO_UDP) { 547 /* UDP validates ulen. */ 548 549 /* Check for jumbo payload */ 550 if (ulen == 0) 551 ulen = skb->len; 552 553 if (ulen < sizeof(*uh)) 554 goto short_packet; 555 556 if (ulen < skb->len) { 557 if (pskb_trim_rcsum(skb, ulen)) 558 goto short_packet; 559 saddr = &ipv6_hdr(skb)->saddr; 560 daddr = &ipv6_hdr(skb)->daddr; 561 uh = udp_hdr(skb); 562 } 563 } 564 565 if (udp6_csum_init(skb, uh, proto)) 566 goto discard; 567 568 /* 569 * Multicast receive code 570 */ 571 if (ipv6_addr_is_multicast(daddr)) 572 return __udp6_lib_mcast_deliver(net, skb, 573 saddr, daddr, udptable); 574 575 /* Unicast */ 576 577 /* 578 * check socket cache ... must talk to Alan about his plans 579 * for sock caches... i'll skip this for now. 580 */ 581 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable); 582 583 if (sk == NULL) { 584 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 585 goto discard; 586 587 if (udp_lib_checksum_complete(skb)) 588 goto discard; 589 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, 590 proto == IPPROTO_UDPLITE); 591 592 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0, dev); 593 594 kfree_skb(skb); 595 return 0; 596 } 597 598 /* deliver */ 599 600 bh_lock_sock(sk); 601 if (!sock_owned_by_user(sk)) 602 udpv6_queue_rcv_skb(sk, skb); 603 else 604 sk_add_backlog(sk, skb); 605 bh_unlock_sock(sk); 606 sock_put(sk); 607 return 0; 608 609 short_packet: 610 LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: %d/%u\n", 611 proto == IPPROTO_UDPLITE ? "-Lite" : "", 612 ulen, skb->len); 613 614 discard: 615 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); 616 kfree_skb(skb); 617 return 0; 618 } 619 620 static __inline__ int udpv6_rcv(struct sk_buff *skb) 621 { 622 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP); 623 } 624 625 /* 626 * Throw away all pending data and cancel the corking. Socket is locked. 627 */ 628 static void udp_v6_flush_pending_frames(struct sock *sk) 629 { 630 struct udp_sock *up = udp_sk(sk); 631 632 if (up->pending == AF_INET) 633 udp_flush_pending_frames(sk); 634 else if (up->pending) { 635 up->len = 0; 636 up->pending = 0; 637 ip6_flush_pending_frames(sk); 638 } 639 } 640 641 /* 642 * Sending 643 */ 644 645 static int udp_v6_push_pending_frames(struct sock *sk) 646 { 647 struct sk_buff *skb; 648 struct udphdr *uh; 649 struct udp_sock *up = udp_sk(sk); 650 struct inet_sock *inet = inet_sk(sk); 651 struct flowi *fl = &inet->cork.fl; 652 int err = 0; 653 int is_udplite = IS_UDPLITE(sk); 654 __wsum csum = 0; 655 656 /* Grab the skbuff where UDP header space exists. */ 657 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL) 658 goto out; 659 660 /* 661 * Create a UDP header 662 */ 663 uh = udp_hdr(skb); 664 uh->source = fl->fl_ip_sport; 665 uh->dest = fl->fl_ip_dport; 666 uh->len = htons(up->len); 667 uh->check = 0; 668 669 if (is_udplite) 670 csum = udplite_csum_outgoing(sk, skb); 671 else 672 csum = udp_csum_outgoing(sk, skb); 673 674 /* add protocol-dependent pseudo-header */ 675 uh->check = csum_ipv6_magic(&fl->fl6_src, &fl->fl6_dst, 676 up->len, fl->proto, csum ); 677 if (uh->check == 0) 678 uh->check = CSUM_MANGLED_0; 679 680 err = ip6_push_pending_frames(sk); 681 out: 682 up->len = 0; 683 up->pending = 0; 684 if (!err) 685 UDP6_INC_STATS_USER(sock_net(sk), 686 UDP_MIB_OUTDATAGRAMS, is_udplite); 687 return err; 688 } 689 690 int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk, 691 struct msghdr *msg, size_t len) 692 { 693 struct ipv6_txoptions opt_space; 694 struct udp_sock *up = udp_sk(sk); 695 struct inet_sock *inet = inet_sk(sk); 696 struct ipv6_pinfo *np = inet6_sk(sk); 697 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name; 698 struct in6_addr *daddr, *final_p = NULL, final; 699 struct ipv6_txoptions *opt = NULL; 700 struct ip6_flowlabel *flowlabel = NULL; 701 struct flowi fl; 702 struct dst_entry *dst; 703 int addr_len = msg->msg_namelen; 704 int ulen = len; 705 int hlimit = -1; 706 int tclass = -1; 707 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; 708 int err; 709 int connected = 0; 710 int is_udplite = IS_UDPLITE(sk); 711 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); 712 713 /* destination address check */ 714 if (sin6) { 715 if (addr_len < offsetof(struct sockaddr, sa_data)) 716 return -EINVAL; 717 718 switch (sin6->sin6_family) { 719 case AF_INET6: 720 if (addr_len < SIN6_LEN_RFC2133) 721 return -EINVAL; 722 daddr = &sin6->sin6_addr; 723 break; 724 case AF_INET: 725 goto do_udp_sendmsg; 726 case AF_UNSPEC: 727 msg->msg_name = sin6 = NULL; 728 msg->msg_namelen = addr_len = 0; 729 daddr = NULL; 730 break; 731 default: 732 return -EINVAL; 733 } 734 } else if (!up->pending) { 735 if (sk->sk_state != TCP_ESTABLISHED) 736 return -EDESTADDRREQ; 737 daddr = &np->daddr; 738 } else 739 daddr = NULL; 740 741 if (daddr) { 742 if (ipv6_addr_v4mapped(daddr)) { 743 struct sockaddr_in sin; 744 sin.sin_family = AF_INET; 745 sin.sin_port = sin6 ? sin6->sin6_port : inet->dport; 746 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 747 msg->msg_name = &sin; 748 msg->msg_namelen = sizeof(sin); 749 do_udp_sendmsg: 750 if (__ipv6_only_sock(sk)) 751 return -ENETUNREACH; 752 return udp_sendmsg(iocb, sk, msg, len); 753 } 754 } 755 756 if (up->pending == AF_INET) 757 return udp_sendmsg(iocb, sk, msg, len); 758 759 /* Rough check on arithmetic overflow, 760 better check is made in ip6_append_data(). 761 */ 762 if (len > INT_MAX - sizeof(struct udphdr)) 763 return -EMSGSIZE; 764 765 if (up->pending) { 766 /* 767 * There are pending frames. 768 * The socket lock must be held while it's corked. 769 */ 770 lock_sock(sk); 771 if (likely(up->pending)) { 772 if (unlikely(up->pending != AF_INET6)) { 773 release_sock(sk); 774 return -EAFNOSUPPORT; 775 } 776 dst = NULL; 777 goto do_append_data; 778 } 779 release_sock(sk); 780 } 781 ulen += sizeof(struct udphdr); 782 783 memset(&fl, 0, sizeof(fl)); 784 785 if (sin6) { 786 if (sin6->sin6_port == 0) 787 return -EINVAL; 788 789 fl.fl_ip_dport = sin6->sin6_port; 790 daddr = &sin6->sin6_addr; 791 792 if (np->sndflow) { 793 fl.fl6_flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK; 794 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) { 795 flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel); 796 if (flowlabel == NULL) 797 return -EINVAL; 798 daddr = &flowlabel->dst; 799 } 800 } 801 802 /* 803 * Otherwise it will be difficult to maintain 804 * sk->sk_dst_cache. 805 */ 806 if (sk->sk_state == TCP_ESTABLISHED && 807 ipv6_addr_equal(daddr, &np->daddr)) 808 daddr = &np->daddr; 809 810 if (addr_len >= sizeof(struct sockaddr_in6) && 811 sin6->sin6_scope_id && 812 ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL) 813 fl.oif = sin6->sin6_scope_id; 814 } else { 815 if (sk->sk_state != TCP_ESTABLISHED) 816 return -EDESTADDRREQ; 817 818 fl.fl_ip_dport = inet->dport; 819 daddr = &np->daddr; 820 fl.fl6_flowlabel = np->flow_label; 821 connected = 1; 822 } 823 824 if (!fl.oif) 825 fl.oif = sk->sk_bound_dev_if; 826 827 if (!fl.oif) 828 fl.oif = np->sticky_pktinfo.ipi6_ifindex; 829 830 if (msg->msg_controllen) { 831 opt = &opt_space; 832 memset(opt, 0, sizeof(struct ipv6_txoptions)); 833 opt->tot_len = sizeof(*opt); 834 835 err = datagram_send_ctl(sock_net(sk), msg, &fl, opt, &hlimit, &tclass); 836 if (err < 0) { 837 fl6_sock_release(flowlabel); 838 return err; 839 } 840 if ((fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) { 841 flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel); 842 if (flowlabel == NULL) 843 return -EINVAL; 844 } 845 if (!(opt->opt_nflen|opt->opt_flen)) 846 opt = NULL; 847 connected = 0; 848 } 849 if (opt == NULL) 850 opt = np->opt; 851 if (flowlabel) 852 opt = fl6_merge_options(&opt_space, flowlabel, opt); 853 opt = ipv6_fixup_options(&opt_space, opt); 854 855 fl.proto = sk->sk_protocol; 856 if (!ipv6_addr_any(daddr)) 857 ipv6_addr_copy(&fl.fl6_dst, daddr); 858 else 859 fl.fl6_dst.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */ 860 if (ipv6_addr_any(&fl.fl6_src) && !ipv6_addr_any(&np->saddr)) 861 ipv6_addr_copy(&fl.fl6_src, &np->saddr); 862 fl.fl_ip_sport = inet->sport; 863 864 /* merge ip6_build_xmit from ip6_output */ 865 if (opt && opt->srcrt) { 866 struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; 867 ipv6_addr_copy(&final, &fl.fl6_dst); 868 ipv6_addr_copy(&fl.fl6_dst, rt0->addr); 869 final_p = &final; 870 connected = 0; 871 } 872 873 if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst)) { 874 fl.oif = np->mcast_oif; 875 connected = 0; 876 } 877 878 security_sk_classify_flow(sk, &fl); 879 880 err = ip6_sk_dst_lookup(sk, &dst, &fl); 881 if (err) 882 goto out; 883 if (final_p) 884 ipv6_addr_copy(&fl.fl6_dst, final_p); 885 886 err = __xfrm_lookup(sock_net(sk), &dst, &fl, sk, XFRM_LOOKUP_WAIT); 887 if (err < 0) { 888 if (err == -EREMOTE) 889 err = ip6_dst_blackhole(sk, &dst, &fl); 890 if (err < 0) 891 goto out; 892 } 893 894 if (hlimit < 0) { 895 if (ipv6_addr_is_multicast(&fl.fl6_dst)) 896 hlimit = np->mcast_hops; 897 else 898 hlimit = np->hop_limit; 899 if (hlimit < 0) 900 hlimit = ip6_dst_hoplimit(dst); 901 } 902 903 if (tclass < 0) { 904 tclass = np->tclass; 905 if (tclass < 0) 906 tclass = 0; 907 } 908 909 if (msg->msg_flags&MSG_CONFIRM) 910 goto do_confirm; 911 back_from_confirm: 912 913 lock_sock(sk); 914 if (unlikely(up->pending)) { 915 /* The socket is already corked while preparing it. */ 916 /* ... which is an evident application bug. --ANK */ 917 release_sock(sk); 918 919 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n"); 920 err = -EINVAL; 921 goto out; 922 } 923 924 up->pending = AF_INET6; 925 926 do_append_data: 927 up->len += ulen; 928 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; 929 err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen, 930 sizeof(struct udphdr), hlimit, tclass, opt, &fl, 931 (struct rt6_info*)dst, 932 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags); 933 if (err) 934 udp_v6_flush_pending_frames(sk); 935 else if (!corkreq) 936 err = udp_v6_push_pending_frames(sk); 937 else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) 938 up->pending = 0; 939 940 if (dst) { 941 if (connected) { 942 ip6_dst_store(sk, dst, 943 ipv6_addr_equal(&fl.fl6_dst, &np->daddr) ? 944 &np->daddr : NULL, 945 #ifdef CONFIG_IPV6_SUBTREES 946 ipv6_addr_equal(&fl.fl6_src, &np->saddr) ? 947 &np->saddr : 948 #endif 949 NULL); 950 } else { 951 dst_release(dst); 952 } 953 dst = NULL; 954 } 955 956 if (err > 0) 957 err = np->recverr ? net_xmit_errno(err) : 0; 958 release_sock(sk); 959 out: 960 dst_release(dst); 961 fl6_sock_release(flowlabel); 962 if (!err) 963 return len; 964 /* 965 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting 966 * ENOBUFS might not be good (it's not tunable per se), but otherwise 967 * we don't have a good statistic (IpOutDiscards but it can be too many 968 * things). We could add another new stat but at least for now that 969 * seems like overkill. 970 */ 971 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { 972 UDP6_INC_STATS_USER(sock_net(sk), 973 UDP_MIB_SNDBUFERRORS, is_udplite); 974 } 975 return err; 976 977 do_confirm: 978 dst_confirm(dst); 979 if (!(msg->msg_flags&MSG_PROBE) || len) 980 goto back_from_confirm; 981 err = 0; 982 goto out; 983 } 984 985 void udpv6_destroy_sock(struct sock *sk) 986 { 987 lock_sock(sk); 988 udp_v6_flush_pending_frames(sk); 989 release_sock(sk); 990 991 inet6_destroy_sock(sk); 992 } 993 994 /* 995 * Socket option code for UDP 996 */ 997 int udpv6_setsockopt(struct sock *sk, int level, int optname, 998 char __user *optval, int optlen) 999 { 1000 if (level == SOL_UDP || level == SOL_UDPLITE) 1001 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1002 udp_v6_push_pending_frames); 1003 return ipv6_setsockopt(sk, level, optname, optval, optlen); 1004 } 1005 1006 #ifdef CONFIG_COMPAT 1007 int compat_udpv6_setsockopt(struct sock *sk, int level, int optname, 1008 char __user *optval, int optlen) 1009 { 1010 if (level == SOL_UDP || level == SOL_UDPLITE) 1011 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1012 udp_v6_push_pending_frames); 1013 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen); 1014 } 1015 #endif 1016 1017 int udpv6_getsockopt(struct sock *sk, int level, int optname, 1018 char __user *optval, int __user *optlen) 1019 { 1020 if (level == SOL_UDP || level == SOL_UDPLITE) 1021 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1022 return ipv6_getsockopt(sk, level, optname, optval, optlen); 1023 } 1024 1025 #ifdef CONFIG_COMPAT 1026 int compat_udpv6_getsockopt(struct sock *sk, int level, int optname, 1027 char __user *optval, int __user *optlen) 1028 { 1029 if (level == SOL_UDP || level == SOL_UDPLITE) 1030 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1031 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen); 1032 } 1033 #endif 1034 1035 static struct inet6_protocol udpv6_protocol = { 1036 .handler = udpv6_rcv, 1037 .err_handler = udpv6_err, 1038 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1039 }; 1040 1041 /* ------------------------------------------------------------------------ */ 1042 #ifdef CONFIG_PROC_FS 1043 1044 static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket) 1045 { 1046 struct inet_sock *inet = inet_sk(sp); 1047 struct ipv6_pinfo *np = inet6_sk(sp); 1048 struct in6_addr *dest, *src; 1049 __u16 destp, srcp; 1050 1051 dest = &np->daddr; 1052 src = &np->rcv_saddr; 1053 destp = ntohs(inet->dport); 1054 srcp = ntohs(inet->sport); 1055 seq_printf(seq, 1056 "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1057 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %d\n", 1058 bucket, 1059 src->s6_addr32[0], src->s6_addr32[1], 1060 src->s6_addr32[2], src->s6_addr32[3], srcp, 1061 dest->s6_addr32[0], dest->s6_addr32[1], 1062 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1063 sp->sk_state, 1064 sk_wmem_alloc_get(sp), 1065 sk_rmem_alloc_get(sp), 1066 0, 0L, 0, 1067 sock_i_uid(sp), 0, 1068 sock_i_ino(sp), 1069 atomic_read(&sp->sk_refcnt), sp, 1070 atomic_read(&sp->sk_drops)); 1071 } 1072 1073 int udp6_seq_show(struct seq_file *seq, void *v) 1074 { 1075 if (v == SEQ_START_TOKEN) 1076 seq_printf(seq, 1077 " sl " 1078 "local_address " 1079 "remote_address " 1080 "st tx_queue rx_queue tr tm->when retrnsmt" 1081 " uid timeout inode ref pointer drops\n"); 1082 else 1083 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket); 1084 return 0; 1085 } 1086 1087 static struct udp_seq_afinfo udp6_seq_afinfo = { 1088 .name = "udp6", 1089 .family = AF_INET6, 1090 .udp_table = &udp_table, 1091 .seq_fops = { 1092 .owner = THIS_MODULE, 1093 }, 1094 .seq_ops = { 1095 .show = udp6_seq_show, 1096 }, 1097 }; 1098 1099 int udp6_proc_init(struct net *net) 1100 { 1101 return udp_proc_register(net, &udp6_seq_afinfo); 1102 } 1103 1104 void udp6_proc_exit(struct net *net) { 1105 udp_proc_unregister(net, &udp6_seq_afinfo); 1106 } 1107 #endif /* CONFIG_PROC_FS */ 1108 1109 /* ------------------------------------------------------------------------ */ 1110 1111 struct proto udpv6_prot = { 1112 .name = "UDPv6", 1113 .owner = THIS_MODULE, 1114 .close = udp_lib_close, 1115 .connect = ip6_datagram_connect, 1116 .disconnect = udp_disconnect, 1117 .ioctl = udp_ioctl, 1118 .destroy = udpv6_destroy_sock, 1119 .setsockopt = udpv6_setsockopt, 1120 .getsockopt = udpv6_getsockopt, 1121 .sendmsg = udpv6_sendmsg, 1122 .recvmsg = udpv6_recvmsg, 1123 .backlog_rcv = udpv6_queue_rcv_skb, 1124 .hash = udp_lib_hash, 1125 .unhash = udp_lib_unhash, 1126 .get_port = udp_v6_get_port, 1127 .memory_allocated = &udp_memory_allocated, 1128 .sysctl_mem = sysctl_udp_mem, 1129 .sysctl_wmem = &sysctl_udp_wmem_min, 1130 .sysctl_rmem = &sysctl_udp_rmem_min, 1131 .obj_size = sizeof(struct udp6_sock), 1132 .slab_flags = SLAB_DESTROY_BY_RCU, 1133 .h.udp_table = &udp_table, 1134 #ifdef CONFIG_COMPAT 1135 .compat_setsockopt = compat_udpv6_setsockopt, 1136 .compat_getsockopt = compat_udpv6_getsockopt, 1137 #endif 1138 }; 1139 1140 static struct inet_protosw udpv6_protosw = { 1141 .type = SOCK_DGRAM, 1142 .protocol = IPPROTO_UDP, 1143 .prot = &udpv6_prot, 1144 .ops = &inet6_dgram_ops, 1145 .capability =-1, 1146 .no_check = UDP_CSUM_DEFAULT, 1147 .flags = INET_PROTOSW_PERMANENT, 1148 }; 1149 1150 1151 int __init udpv6_init(void) 1152 { 1153 int ret; 1154 1155 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP); 1156 if (ret) 1157 goto out; 1158 1159 ret = inet6_register_protosw(&udpv6_protosw); 1160 if (ret) 1161 goto out_udpv6_protocol; 1162 out: 1163 return ret; 1164 1165 out_udpv6_protocol: 1166 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1167 goto out; 1168 } 1169 1170 void udpv6_exit(void) 1171 { 1172 inet6_unregister_protosw(&udpv6_protosw); 1173 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1174 } 1175