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 49 #include <linux/proc_fs.h> 50 #include <linux/seq_file.h> 51 #include "udp_impl.h" 52 53 int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2) 54 { 55 const struct in6_addr *sk_rcv_saddr6 = &inet6_sk(sk)->rcv_saddr; 56 const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2); 57 __be32 sk1_rcv_saddr = sk_rcv_saddr(sk); 58 __be32 sk2_rcv_saddr = sk_rcv_saddr(sk2); 59 int sk_ipv6only = ipv6_only_sock(sk); 60 int sk2_ipv6only = inet_v6_ipv6only(sk2); 61 int addr_type = ipv6_addr_type(sk_rcv_saddr6); 62 int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED; 63 64 /* if both are mapped, treat as IPv4 */ 65 if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED) 66 return (!sk2_ipv6only && 67 (!sk1_rcv_saddr || !sk2_rcv_saddr || 68 sk1_rcv_saddr == sk2_rcv_saddr)); 69 70 if (addr_type2 == IPV6_ADDR_ANY && 71 !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED)) 72 return 1; 73 74 if (addr_type == IPV6_ADDR_ANY && 75 !(sk_ipv6only && addr_type2 == IPV6_ADDR_MAPPED)) 76 return 1; 77 78 if (sk2_rcv_saddr6 && 79 ipv6_addr_equal(sk_rcv_saddr6, sk2_rcv_saddr6)) 80 return 1; 81 82 return 0; 83 } 84 85 static unsigned int udp6_portaddr_hash(struct net *net, 86 const struct in6_addr *addr6, 87 unsigned int port) 88 { 89 unsigned int hash, mix = net_hash_mix(net); 90 91 if (ipv6_addr_any(addr6)) 92 hash = jhash_1word(0, mix); 93 else if (ipv6_addr_v4mapped(addr6)) 94 hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix); 95 else 96 hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix); 97 98 return hash ^ port; 99 } 100 101 102 int udp_v6_get_port(struct sock *sk, unsigned short snum) 103 { 104 unsigned int hash2_nulladdr = 105 udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum); 106 unsigned int hash2_partial = 107 udp6_portaddr_hash(sock_net(sk), &inet6_sk(sk)->rcv_saddr, 0); 108 109 /* precompute partial secondary hash */ 110 udp_sk(sk)->udp_portaddr_hash = hash2_partial; 111 return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr); 112 } 113 114 static void udp_v6_rehash(struct sock *sk) 115 { 116 u16 new_hash = udp6_portaddr_hash(sock_net(sk), 117 &inet6_sk(sk)->rcv_saddr, 118 inet_sk(sk)->inet_num); 119 120 udp_lib_rehash(sk, new_hash); 121 } 122 123 static inline int compute_score(struct sock *sk, struct net *net, 124 unsigned short hnum, 125 const struct in6_addr *saddr, __be16 sport, 126 const struct in6_addr *daddr, __be16 dport, 127 int dif) 128 { 129 int score = -1; 130 131 if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum && 132 sk->sk_family == PF_INET6) { 133 struct ipv6_pinfo *np = inet6_sk(sk); 134 struct inet_sock *inet = inet_sk(sk); 135 136 score = 0; 137 if (inet->inet_dport) { 138 if (inet->inet_dport != sport) 139 return -1; 140 score++; 141 } 142 if (!ipv6_addr_any(&np->rcv_saddr)) { 143 if (!ipv6_addr_equal(&np->rcv_saddr, daddr)) 144 return -1; 145 score++; 146 } 147 if (!ipv6_addr_any(&np->daddr)) { 148 if (!ipv6_addr_equal(&np->daddr, saddr)) 149 return -1; 150 score++; 151 } 152 if (sk->sk_bound_dev_if) { 153 if (sk->sk_bound_dev_if != dif) 154 return -1; 155 score++; 156 } 157 } 158 return score; 159 } 160 161 #define SCORE2_MAX (1 + 1 + 1) 162 static inline int compute_score2(struct sock *sk, struct net *net, 163 const struct in6_addr *saddr, __be16 sport, 164 const struct in6_addr *daddr, unsigned short hnum, 165 int dif) 166 { 167 int score = -1; 168 169 if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum && 170 sk->sk_family == PF_INET6) { 171 struct ipv6_pinfo *np = inet6_sk(sk); 172 struct inet_sock *inet = inet_sk(sk); 173 174 if (!ipv6_addr_equal(&np->rcv_saddr, daddr)) 175 return -1; 176 score = 0; 177 if (inet->inet_dport) { 178 if (inet->inet_dport != sport) 179 return -1; 180 score++; 181 } 182 if (!ipv6_addr_any(&np->daddr)) { 183 if (!ipv6_addr_equal(&np->daddr, saddr)) 184 return -1; 185 score++; 186 } 187 if (sk->sk_bound_dev_if) { 188 if (sk->sk_bound_dev_if != dif) 189 return -1; 190 score++; 191 } 192 } 193 return score; 194 } 195 196 197 /* called with read_rcu_lock() */ 198 static struct sock *udp6_lib_lookup2(struct net *net, 199 const struct in6_addr *saddr, __be16 sport, 200 const struct in6_addr *daddr, unsigned int hnum, int dif, 201 struct udp_hslot *hslot2, unsigned int slot2) 202 { 203 struct sock *sk, *result; 204 struct hlist_nulls_node *node; 205 int score, badness; 206 207 begin: 208 result = NULL; 209 badness = -1; 210 udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) { 211 score = compute_score2(sk, net, saddr, sport, 212 daddr, hnum, dif); 213 if (score > badness) { 214 result = sk; 215 badness = score; 216 if (score == SCORE2_MAX) 217 goto exact_match; 218 } 219 } 220 /* 221 * if the nulls value we got at the end of this lookup is 222 * not the expected one, we must restart lookup. 223 * We probably met an item that was moved to another chain. 224 */ 225 if (get_nulls_value(node) != slot2) 226 goto begin; 227 228 if (result) { 229 exact_match: 230 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2))) 231 result = NULL; 232 else if (unlikely(compute_score2(result, net, saddr, sport, 233 daddr, hnum, dif) < badness)) { 234 sock_put(result); 235 goto begin; 236 } 237 } 238 return result; 239 } 240 241 struct sock *__udp6_lib_lookup(struct net *net, 242 const struct in6_addr *saddr, __be16 sport, 243 const struct in6_addr *daddr, __be16 dport, 244 int dif, struct udp_table *udptable) 245 { 246 struct sock *sk, *result; 247 struct hlist_nulls_node *node; 248 unsigned short hnum = ntohs(dport); 249 unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask); 250 struct udp_hslot *hslot2, *hslot = &udptable->hash[slot]; 251 int score, badness; 252 253 rcu_read_lock(); 254 if (hslot->count > 10) { 255 hash2 = udp6_portaddr_hash(net, daddr, hnum); 256 slot2 = hash2 & udptable->mask; 257 hslot2 = &udptable->hash2[slot2]; 258 if (hslot->count < hslot2->count) 259 goto begin; 260 261 result = udp6_lib_lookup2(net, saddr, sport, 262 daddr, hnum, dif, 263 hslot2, slot2); 264 if (!result) { 265 hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum); 266 slot2 = hash2 & udptable->mask; 267 hslot2 = &udptable->hash2[slot2]; 268 if (hslot->count < hslot2->count) 269 goto begin; 270 271 result = udp6_lib_lookup2(net, saddr, sport, 272 &in6addr_any, hnum, dif, 273 hslot2, slot2); 274 } 275 rcu_read_unlock(); 276 return result; 277 } 278 begin: 279 result = NULL; 280 badness = -1; 281 sk_nulls_for_each_rcu(sk, node, &hslot->head) { 282 score = compute_score(sk, net, hnum, saddr, sport, daddr, dport, dif); 283 if (score > badness) { 284 result = sk; 285 badness = score; 286 } 287 } 288 /* 289 * if the nulls value we got at the end of this lookup is 290 * not the expected one, we must restart lookup. 291 * We probably met an item that was moved to another chain. 292 */ 293 if (get_nulls_value(node) != slot) 294 goto begin; 295 296 if (result) { 297 if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2))) 298 result = NULL; 299 else if (unlikely(compute_score(result, net, hnum, saddr, sport, 300 daddr, dport, dif) < badness)) { 301 sock_put(result); 302 goto begin; 303 } 304 } 305 rcu_read_unlock(); 306 return result; 307 } 308 EXPORT_SYMBOL_GPL(__udp6_lib_lookup); 309 310 static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb, 311 __be16 sport, __be16 dport, 312 struct udp_table *udptable) 313 { 314 struct sock *sk; 315 const struct ipv6hdr *iph = ipv6_hdr(skb); 316 317 if (unlikely(sk = skb_steal_sock(skb))) 318 return sk; 319 return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport, 320 &iph->daddr, dport, inet6_iif(skb), 321 udptable); 322 } 323 324 struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport, 325 const struct in6_addr *daddr, __be16 dport, int dif) 326 { 327 return __udp6_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table); 328 } 329 EXPORT_SYMBOL_GPL(udp6_lib_lookup); 330 331 332 /* 333 * This should be easy, if there is something there we 334 * return it, otherwise we block. 335 */ 336 337 int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk, 338 struct msghdr *msg, size_t len, 339 int noblock, int flags, int *addr_len) 340 { 341 struct ipv6_pinfo *np = inet6_sk(sk); 342 struct inet_sock *inet = inet_sk(sk); 343 struct sk_buff *skb; 344 unsigned int ulen, copied; 345 int peeked, off = 0; 346 int err; 347 int is_udplite = IS_UDPLITE(sk); 348 int is_udp4; 349 bool slow; 350 351 if (addr_len) 352 *addr_len=sizeof(struct sockaddr_in6); 353 354 if (flags & MSG_ERRQUEUE) 355 return ipv6_recv_error(sk, msg, len); 356 357 if (np->rxpmtu && np->rxopt.bits.rxpmtu) 358 return ipv6_recv_rxpmtu(sk, msg, len); 359 360 try_again: 361 skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0), 362 &peeked, &off, &err); 363 if (!skb) 364 goto out; 365 366 ulen = skb->len - sizeof(struct udphdr); 367 copied = len; 368 if (copied > ulen) 369 copied = ulen; 370 else if (copied < ulen) 371 msg->msg_flags |= MSG_TRUNC; 372 373 is_udp4 = (skb->protocol == htons(ETH_P_IP)); 374 375 /* 376 * If checksum is needed at all, try to do it while copying the 377 * data. If the data is truncated, or if we only want a partial 378 * coverage checksum (UDP-Lite), do it before the copy. 379 */ 380 381 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) { 382 if (udp_lib_checksum_complete(skb)) 383 goto csum_copy_err; 384 } 385 386 if (skb_csum_unnecessary(skb)) 387 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), 388 msg->msg_iov, copied ); 389 else { 390 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov); 391 if (err == -EINVAL) 392 goto csum_copy_err; 393 } 394 if (err) 395 goto out_free; 396 397 if (!peeked) { 398 if (is_udp4) 399 UDP_INC_STATS_USER(sock_net(sk), 400 UDP_MIB_INDATAGRAMS, is_udplite); 401 else 402 UDP6_INC_STATS_USER(sock_net(sk), 403 UDP_MIB_INDATAGRAMS, is_udplite); 404 } 405 406 sock_recv_ts_and_drops(msg, sk, skb); 407 408 /* Copy the address. */ 409 if (msg->msg_name) { 410 struct sockaddr_in6 *sin6; 411 412 sin6 = (struct sockaddr_in6 *) msg->msg_name; 413 sin6->sin6_family = AF_INET6; 414 sin6->sin6_port = udp_hdr(skb)->source; 415 sin6->sin6_flowinfo = 0; 416 sin6->sin6_scope_id = 0; 417 418 if (is_udp4) 419 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 420 &sin6->sin6_addr); 421 else { 422 sin6->sin6_addr = ipv6_hdr(skb)->saddr; 423 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) 424 sin6->sin6_scope_id = IP6CB(skb)->iif; 425 } 426 427 } 428 if (is_udp4) { 429 if (inet->cmsg_flags) 430 ip_cmsg_recv(msg, skb); 431 } else { 432 if (np->rxopt.all) 433 datagram_recv_ctl(sk, msg, skb); 434 } 435 436 err = copied; 437 if (flags & MSG_TRUNC) 438 err = ulen; 439 440 out_free: 441 skb_free_datagram_locked(sk, skb); 442 out: 443 return err; 444 445 csum_copy_err: 446 slow = lock_sock_fast(sk); 447 if (!skb_kill_datagram(sk, skb, flags)) { 448 if (is_udp4) 449 UDP_INC_STATS_USER(sock_net(sk), 450 UDP_MIB_INERRORS, is_udplite); 451 else 452 UDP6_INC_STATS_USER(sock_net(sk), 453 UDP_MIB_INERRORS, is_udplite); 454 } 455 unlock_sock_fast(sk, slow); 456 457 if (noblock) 458 return -EAGAIN; 459 460 /* starting over for a new packet */ 461 msg->msg_flags &= ~MSG_TRUNC; 462 goto try_again; 463 } 464 465 void __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 466 u8 type, u8 code, int offset, __be32 info, 467 struct udp_table *udptable) 468 { 469 struct ipv6_pinfo *np; 470 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; 471 const struct in6_addr *saddr = &hdr->saddr; 472 const struct in6_addr *daddr = &hdr->daddr; 473 struct udphdr *uh = (struct udphdr*)(skb->data+offset); 474 struct sock *sk; 475 int err; 476 477 sk = __udp6_lib_lookup(dev_net(skb->dev), daddr, uh->dest, 478 saddr, uh->source, inet6_iif(skb), udptable); 479 if (sk == NULL) 480 return; 481 482 np = inet6_sk(sk); 483 484 if (!icmpv6_err_convert(type, code, &err) && !np->recverr) 485 goto out; 486 487 if (sk->sk_state != TCP_ESTABLISHED && !np->recverr) 488 goto out; 489 490 if (np->recverr) 491 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1)); 492 493 sk->sk_err = err; 494 sk->sk_error_report(sk); 495 out: 496 sock_put(sk); 497 } 498 499 static __inline__ void udpv6_err(struct sk_buff *skb, 500 struct inet6_skb_parm *opt, u8 type, 501 u8 code, int offset, __be32 info ) 502 { 503 __udp6_lib_err(skb, opt, type, code, offset, info, &udp_table); 504 } 505 506 int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) 507 { 508 struct udp_sock *up = udp_sk(sk); 509 int rc; 510 int is_udplite = IS_UDPLITE(sk); 511 512 if (!ipv6_addr_any(&inet6_sk(sk)->daddr)) 513 sock_rps_save_rxhash(sk, skb); 514 515 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) 516 goto drop; 517 518 /* 519 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c). 520 */ 521 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { 522 523 if (up->pcrlen == 0) { /* full coverage was set */ 524 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: partial coverage" 525 " %d while full coverage %d requested\n", 526 UDP_SKB_CB(skb)->cscov, skb->len); 527 goto drop; 528 } 529 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { 530 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE6: coverage %d " 531 "too small, need min %d\n", 532 UDP_SKB_CB(skb)->cscov, up->pcrlen); 533 goto drop; 534 } 535 } 536 537 if (rcu_access_pointer(sk->sk_filter)) { 538 if (udp_lib_checksum_complete(skb)) 539 goto drop; 540 } 541 542 skb_dst_drop(skb); 543 rc = sock_queue_rcv_skb(sk, skb); 544 if (rc < 0) { 545 /* Note that an ENOMEM error is charged twice */ 546 if (rc == -ENOMEM) 547 UDP6_INC_STATS_BH(sock_net(sk), 548 UDP_MIB_RCVBUFERRORS, is_udplite); 549 goto drop_no_sk_drops_inc; 550 } 551 552 return 0; 553 drop: 554 atomic_inc(&sk->sk_drops); 555 drop_no_sk_drops_inc: 556 UDP6_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 557 kfree_skb(skb); 558 return -1; 559 } 560 561 static struct sock *udp_v6_mcast_next(struct net *net, struct sock *sk, 562 __be16 loc_port, const struct in6_addr *loc_addr, 563 __be16 rmt_port, const struct in6_addr *rmt_addr, 564 int dif) 565 { 566 struct hlist_nulls_node *node; 567 struct sock *s = sk; 568 unsigned short num = ntohs(loc_port); 569 570 sk_nulls_for_each_from(s, node) { 571 struct inet_sock *inet = inet_sk(s); 572 573 if (!net_eq(sock_net(s), net)) 574 continue; 575 576 if (udp_sk(s)->udp_port_hash == num && 577 s->sk_family == PF_INET6) { 578 struct ipv6_pinfo *np = inet6_sk(s); 579 if (inet->inet_dport) { 580 if (inet->inet_dport != rmt_port) 581 continue; 582 } 583 if (!ipv6_addr_any(&np->daddr) && 584 !ipv6_addr_equal(&np->daddr, rmt_addr)) 585 continue; 586 587 if (s->sk_bound_dev_if && s->sk_bound_dev_if != dif) 588 continue; 589 590 if (!ipv6_addr_any(&np->rcv_saddr)) { 591 if (!ipv6_addr_equal(&np->rcv_saddr, loc_addr)) 592 continue; 593 } 594 if (!inet6_mc_check(s, loc_addr, rmt_addr)) 595 continue; 596 return s; 597 } 598 } 599 return NULL; 600 } 601 602 static void flush_stack(struct sock **stack, unsigned int count, 603 struct sk_buff *skb, unsigned int final) 604 { 605 unsigned int i; 606 struct sock *sk; 607 struct sk_buff *skb1; 608 609 for (i = 0; i < count; i++) { 610 skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC); 611 612 sk = stack[i]; 613 if (skb1) { 614 if (sk_rcvqueues_full(sk, skb1)) { 615 kfree_skb(skb1); 616 goto drop; 617 } 618 bh_lock_sock(sk); 619 if (!sock_owned_by_user(sk)) 620 udpv6_queue_rcv_skb(sk, skb1); 621 else if (sk_add_backlog(sk, skb1)) { 622 kfree_skb(skb1); 623 bh_unlock_sock(sk); 624 goto drop; 625 } 626 bh_unlock_sock(sk); 627 continue; 628 } 629 drop: 630 atomic_inc(&sk->sk_drops); 631 UDP6_INC_STATS_BH(sock_net(sk), 632 UDP_MIB_RCVBUFERRORS, IS_UDPLITE(sk)); 633 UDP6_INC_STATS_BH(sock_net(sk), 634 UDP_MIB_INERRORS, IS_UDPLITE(sk)); 635 } 636 } 637 /* 638 * Note: called only from the BH handler context, 639 * so we don't need to lock the hashes. 640 */ 641 static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, 642 const struct in6_addr *saddr, const struct in6_addr *daddr, 643 struct udp_table *udptable) 644 { 645 struct sock *sk, *stack[256 / sizeof(struct sock *)]; 646 const struct udphdr *uh = udp_hdr(skb); 647 struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest)); 648 int dif; 649 unsigned int i, count = 0; 650 651 spin_lock(&hslot->lock); 652 sk = sk_nulls_head(&hslot->head); 653 dif = inet6_iif(skb); 654 sk = udp_v6_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif); 655 while (sk) { 656 stack[count++] = sk; 657 sk = udp_v6_mcast_next(net, sk_nulls_next(sk), uh->dest, daddr, 658 uh->source, saddr, dif); 659 if (unlikely(count == ARRAY_SIZE(stack))) { 660 if (!sk) 661 break; 662 flush_stack(stack, count, skb, ~0); 663 count = 0; 664 } 665 } 666 /* 667 * before releasing the lock, we must take reference on sockets 668 */ 669 for (i = 0; i < count; i++) 670 sock_hold(stack[i]); 671 672 spin_unlock(&hslot->lock); 673 674 if (count) { 675 flush_stack(stack, count, skb, count - 1); 676 677 for (i = 0; i < count; i++) 678 sock_put(stack[i]); 679 } else { 680 kfree_skb(skb); 681 } 682 return 0; 683 } 684 685 static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, 686 int proto) 687 { 688 int err; 689 690 UDP_SKB_CB(skb)->partial_cov = 0; 691 UDP_SKB_CB(skb)->cscov = skb->len; 692 693 if (proto == IPPROTO_UDPLITE) { 694 err = udplite_checksum_init(skb, uh); 695 if (err) 696 return err; 697 } 698 699 if (uh->check == 0) { 700 /* RFC 2460 section 8.1 says that we SHOULD log 701 this error. Well, it is reasonable. 702 */ 703 LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n"); 704 return 1; 705 } 706 if (skb->ip_summed == CHECKSUM_COMPLETE && 707 !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr, 708 skb->len, proto, skb->csum)) 709 skb->ip_summed = CHECKSUM_UNNECESSARY; 710 711 if (!skb_csum_unnecessary(skb)) 712 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr, 713 &ipv6_hdr(skb)->daddr, 714 skb->len, proto, 0)); 715 716 return 0; 717 } 718 719 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, 720 int proto) 721 { 722 struct net *net = dev_net(skb->dev); 723 struct sock *sk; 724 struct udphdr *uh; 725 const struct in6_addr *saddr, *daddr; 726 u32 ulen = 0; 727 728 if (!pskb_may_pull(skb, sizeof(struct udphdr))) 729 goto discard; 730 731 saddr = &ipv6_hdr(skb)->saddr; 732 daddr = &ipv6_hdr(skb)->daddr; 733 uh = udp_hdr(skb); 734 735 ulen = ntohs(uh->len); 736 if (ulen > skb->len) 737 goto short_packet; 738 739 if (proto == IPPROTO_UDP) { 740 /* UDP validates ulen. */ 741 742 /* Check for jumbo payload */ 743 if (ulen == 0) 744 ulen = skb->len; 745 746 if (ulen < sizeof(*uh)) 747 goto short_packet; 748 749 if (ulen < skb->len) { 750 if (pskb_trim_rcsum(skb, ulen)) 751 goto short_packet; 752 saddr = &ipv6_hdr(skb)->saddr; 753 daddr = &ipv6_hdr(skb)->daddr; 754 uh = udp_hdr(skb); 755 } 756 } 757 758 if (udp6_csum_init(skb, uh, proto)) 759 goto discard; 760 761 /* 762 * Multicast receive code 763 */ 764 if (ipv6_addr_is_multicast(daddr)) 765 return __udp6_lib_mcast_deliver(net, skb, 766 saddr, daddr, udptable); 767 768 /* Unicast */ 769 770 /* 771 * check socket cache ... must talk to Alan about his plans 772 * for sock caches... i'll skip this for now. 773 */ 774 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable); 775 776 if (sk == NULL) { 777 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 778 goto discard; 779 780 if (udp_lib_checksum_complete(skb)) 781 goto discard; 782 UDP6_INC_STATS_BH(net, UDP_MIB_NOPORTS, 783 proto == IPPROTO_UDPLITE); 784 785 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 786 787 kfree_skb(skb); 788 return 0; 789 } 790 791 /* deliver */ 792 793 if (sk_rcvqueues_full(sk, skb)) { 794 sock_put(sk); 795 goto discard; 796 } 797 bh_lock_sock(sk); 798 if (!sock_owned_by_user(sk)) 799 udpv6_queue_rcv_skb(sk, skb); 800 else if (sk_add_backlog(sk, skb)) { 801 atomic_inc(&sk->sk_drops); 802 bh_unlock_sock(sk); 803 sock_put(sk); 804 goto discard; 805 } 806 bh_unlock_sock(sk); 807 sock_put(sk); 808 return 0; 809 810 short_packet: 811 LIMIT_NETDEBUG(KERN_DEBUG "UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n", 812 proto == IPPROTO_UDPLITE ? "-Lite" : "", 813 saddr, 814 ntohs(uh->source), 815 ulen, 816 skb->len, 817 daddr, 818 ntohs(uh->dest)); 819 820 discard: 821 UDP6_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); 822 kfree_skb(skb); 823 return 0; 824 } 825 826 static __inline__ int udpv6_rcv(struct sk_buff *skb) 827 { 828 return __udp6_lib_rcv(skb, &udp_table, IPPROTO_UDP); 829 } 830 831 /* 832 * Throw away all pending data and cancel the corking. Socket is locked. 833 */ 834 static void udp_v6_flush_pending_frames(struct sock *sk) 835 { 836 struct udp_sock *up = udp_sk(sk); 837 838 if (up->pending == AF_INET) 839 udp_flush_pending_frames(sk); 840 else if (up->pending) { 841 up->len = 0; 842 up->pending = 0; 843 ip6_flush_pending_frames(sk); 844 } 845 } 846 847 /** 848 * udp6_hwcsum_outgoing - handle outgoing HW checksumming 849 * @sk: socket we are sending on 850 * @skb: sk_buff containing the filled-in UDP header 851 * (checksum field must be zeroed out) 852 */ 853 static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, 854 const struct in6_addr *saddr, 855 const struct in6_addr *daddr, int len) 856 { 857 unsigned int offset; 858 struct udphdr *uh = udp_hdr(skb); 859 __wsum csum = 0; 860 861 if (skb_queue_len(&sk->sk_write_queue) == 1) { 862 /* Only one fragment on the socket. */ 863 skb->csum_start = skb_transport_header(skb) - skb->head; 864 skb->csum_offset = offsetof(struct udphdr, check); 865 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0); 866 } else { 867 /* 868 * HW-checksum won't work as there are two or more 869 * fragments on the socket so that all csums of sk_buffs 870 * should be together 871 */ 872 offset = skb_transport_offset(skb); 873 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); 874 875 skb->ip_summed = CHECKSUM_NONE; 876 877 skb_queue_walk(&sk->sk_write_queue, skb) { 878 csum = csum_add(csum, skb->csum); 879 } 880 881 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 882 csum); 883 if (uh->check == 0) 884 uh->check = CSUM_MANGLED_0; 885 } 886 } 887 888 /* 889 * Sending 890 */ 891 892 static int udp_v6_push_pending_frames(struct sock *sk) 893 { 894 struct sk_buff *skb; 895 struct udphdr *uh; 896 struct udp_sock *up = udp_sk(sk); 897 struct inet_sock *inet = inet_sk(sk); 898 struct flowi6 *fl6 = &inet->cork.fl.u.ip6; 899 int err = 0; 900 int is_udplite = IS_UDPLITE(sk); 901 __wsum csum = 0; 902 903 /* Grab the skbuff where UDP header space exists. */ 904 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL) 905 goto out; 906 907 /* 908 * Create a UDP header 909 */ 910 uh = udp_hdr(skb); 911 uh->source = fl6->fl6_sport; 912 uh->dest = fl6->fl6_dport; 913 uh->len = htons(up->len); 914 uh->check = 0; 915 916 if (is_udplite) 917 csum = udplite_csum_outgoing(sk, skb); 918 else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ 919 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, 920 up->len); 921 goto send; 922 } else 923 csum = udp_csum_outgoing(sk, skb); 924 925 /* add protocol-dependent pseudo-header */ 926 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr, 927 up->len, fl6->flowi6_proto, csum); 928 if (uh->check == 0) 929 uh->check = CSUM_MANGLED_0; 930 931 send: 932 err = ip6_push_pending_frames(sk); 933 if (err) { 934 if (err == -ENOBUFS && !inet6_sk(sk)->recverr) { 935 UDP6_INC_STATS_USER(sock_net(sk), 936 UDP_MIB_SNDBUFERRORS, is_udplite); 937 err = 0; 938 } 939 } else 940 UDP6_INC_STATS_USER(sock_net(sk), 941 UDP_MIB_OUTDATAGRAMS, is_udplite); 942 out: 943 up->len = 0; 944 up->pending = 0; 945 return err; 946 } 947 948 int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk, 949 struct msghdr *msg, size_t len) 950 { 951 struct ipv6_txoptions opt_space; 952 struct udp_sock *up = udp_sk(sk); 953 struct inet_sock *inet = inet_sk(sk); 954 struct ipv6_pinfo *np = inet6_sk(sk); 955 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name; 956 struct in6_addr *daddr, *final_p, final; 957 struct ipv6_txoptions *opt = NULL; 958 struct ip6_flowlabel *flowlabel = NULL; 959 struct flowi6 fl6; 960 struct dst_entry *dst; 961 int addr_len = msg->msg_namelen; 962 int ulen = len; 963 int hlimit = -1; 964 int tclass = -1; 965 int dontfrag = -1; 966 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; 967 int err; 968 int connected = 0; 969 int is_udplite = IS_UDPLITE(sk); 970 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); 971 972 /* destination address check */ 973 if (sin6) { 974 if (addr_len < offsetof(struct sockaddr, sa_data)) 975 return -EINVAL; 976 977 switch (sin6->sin6_family) { 978 case AF_INET6: 979 if (addr_len < SIN6_LEN_RFC2133) 980 return -EINVAL; 981 daddr = &sin6->sin6_addr; 982 break; 983 case AF_INET: 984 goto do_udp_sendmsg; 985 case AF_UNSPEC: 986 msg->msg_name = sin6 = NULL; 987 msg->msg_namelen = addr_len = 0; 988 daddr = NULL; 989 break; 990 default: 991 return -EINVAL; 992 } 993 } else if (!up->pending) { 994 if (sk->sk_state != TCP_ESTABLISHED) 995 return -EDESTADDRREQ; 996 daddr = &np->daddr; 997 } else 998 daddr = NULL; 999 1000 if (daddr) { 1001 if (ipv6_addr_v4mapped(daddr)) { 1002 struct sockaddr_in sin; 1003 sin.sin_family = AF_INET; 1004 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport; 1005 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 1006 msg->msg_name = &sin; 1007 msg->msg_namelen = sizeof(sin); 1008 do_udp_sendmsg: 1009 if (__ipv6_only_sock(sk)) 1010 return -ENETUNREACH; 1011 return udp_sendmsg(iocb, sk, msg, len); 1012 } 1013 } 1014 1015 if (up->pending == AF_INET) 1016 return udp_sendmsg(iocb, sk, msg, len); 1017 1018 /* Rough check on arithmetic overflow, 1019 better check is made in ip6_append_data(). 1020 */ 1021 if (len > INT_MAX - sizeof(struct udphdr)) 1022 return -EMSGSIZE; 1023 1024 if (up->pending) { 1025 /* 1026 * There are pending frames. 1027 * The socket lock must be held while it's corked. 1028 */ 1029 lock_sock(sk); 1030 if (likely(up->pending)) { 1031 if (unlikely(up->pending != AF_INET6)) { 1032 release_sock(sk); 1033 return -EAFNOSUPPORT; 1034 } 1035 dst = NULL; 1036 goto do_append_data; 1037 } 1038 release_sock(sk); 1039 } 1040 ulen += sizeof(struct udphdr); 1041 1042 memset(&fl6, 0, sizeof(fl6)); 1043 1044 if (sin6) { 1045 if (sin6->sin6_port == 0) 1046 return -EINVAL; 1047 1048 fl6.fl6_dport = sin6->sin6_port; 1049 daddr = &sin6->sin6_addr; 1050 1051 if (np->sndflow) { 1052 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK; 1053 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 1054 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1055 if (flowlabel == NULL) 1056 return -EINVAL; 1057 daddr = &flowlabel->dst; 1058 } 1059 } 1060 1061 /* 1062 * Otherwise it will be difficult to maintain 1063 * sk->sk_dst_cache. 1064 */ 1065 if (sk->sk_state == TCP_ESTABLISHED && 1066 ipv6_addr_equal(daddr, &np->daddr)) 1067 daddr = &np->daddr; 1068 1069 if (addr_len >= sizeof(struct sockaddr_in6) && 1070 sin6->sin6_scope_id && 1071 ipv6_addr_type(daddr)&IPV6_ADDR_LINKLOCAL) 1072 fl6.flowi6_oif = sin6->sin6_scope_id; 1073 } else { 1074 if (sk->sk_state != TCP_ESTABLISHED) 1075 return -EDESTADDRREQ; 1076 1077 fl6.fl6_dport = inet->inet_dport; 1078 daddr = &np->daddr; 1079 fl6.flowlabel = np->flow_label; 1080 connected = 1; 1081 } 1082 1083 if (!fl6.flowi6_oif) 1084 fl6.flowi6_oif = sk->sk_bound_dev_if; 1085 1086 if (!fl6.flowi6_oif) 1087 fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; 1088 1089 fl6.flowi6_mark = sk->sk_mark; 1090 1091 if (msg->msg_controllen) { 1092 opt = &opt_space; 1093 memset(opt, 0, sizeof(struct ipv6_txoptions)); 1094 opt->tot_len = sizeof(*opt); 1095 1096 err = datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt, 1097 &hlimit, &tclass, &dontfrag); 1098 if (err < 0) { 1099 fl6_sock_release(flowlabel); 1100 return err; 1101 } 1102 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) { 1103 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 1104 if (flowlabel == NULL) 1105 return -EINVAL; 1106 } 1107 if (!(opt->opt_nflen|opt->opt_flen)) 1108 opt = NULL; 1109 connected = 0; 1110 } 1111 if (opt == NULL) 1112 opt = np->opt; 1113 if (flowlabel) 1114 opt = fl6_merge_options(&opt_space, flowlabel, opt); 1115 opt = ipv6_fixup_options(&opt_space, opt); 1116 1117 fl6.flowi6_proto = sk->sk_protocol; 1118 if (!ipv6_addr_any(daddr)) 1119 fl6.daddr = *daddr; 1120 else 1121 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */ 1122 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr)) 1123 fl6.saddr = np->saddr; 1124 fl6.fl6_sport = inet->inet_sport; 1125 1126 final_p = fl6_update_dst(&fl6, opt, &final); 1127 if (final_p) 1128 connected = 0; 1129 1130 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) { 1131 fl6.flowi6_oif = np->mcast_oif; 1132 connected = 0; 1133 } else if (!fl6.flowi6_oif) 1134 fl6.flowi6_oif = np->ucast_oif; 1135 1136 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); 1137 1138 dst = ip6_sk_dst_lookup_flow(sk, &fl6, final_p, true); 1139 if (IS_ERR(dst)) { 1140 err = PTR_ERR(dst); 1141 dst = NULL; 1142 goto out; 1143 } 1144 1145 if (hlimit < 0) { 1146 if (ipv6_addr_is_multicast(&fl6.daddr)) 1147 hlimit = np->mcast_hops; 1148 else 1149 hlimit = np->hop_limit; 1150 if (hlimit < 0) 1151 hlimit = ip6_dst_hoplimit(dst); 1152 } 1153 1154 if (tclass < 0) 1155 tclass = np->tclass; 1156 1157 if (dontfrag < 0) 1158 dontfrag = np->dontfrag; 1159 1160 if (msg->msg_flags&MSG_CONFIRM) 1161 goto do_confirm; 1162 back_from_confirm: 1163 1164 lock_sock(sk); 1165 if (unlikely(up->pending)) { 1166 /* The socket is already corked while preparing it. */ 1167 /* ... which is an evident application bug. --ANK */ 1168 release_sock(sk); 1169 1170 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n"); 1171 err = -EINVAL; 1172 goto out; 1173 } 1174 1175 up->pending = AF_INET6; 1176 1177 do_append_data: 1178 up->len += ulen; 1179 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; 1180 err = ip6_append_data(sk, getfrag, msg->msg_iov, ulen, 1181 sizeof(struct udphdr), hlimit, tclass, opt, &fl6, 1182 (struct rt6_info*)dst, 1183 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags, dontfrag); 1184 if (err) 1185 udp_v6_flush_pending_frames(sk); 1186 else if (!corkreq) 1187 err = udp_v6_push_pending_frames(sk); 1188 else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) 1189 up->pending = 0; 1190 1191 if (dst) { 1192 if (connected) { 1193 ip6_dst_store(sk, dst, 1194 ipv6_addr_equal(&fl6.daddr, &np->daddr) ? 1195 &np->daddr : NULL, 1196 #ifdef CONFIG_IPV6_SUBTREES 1197 ipv6_addr_equal(&fl6.saddr, &np->saddr) ? 1198 &np->saddr : 1199 #endif 1200 NULL); 1201 } else { 1202 dst_release(dst); 1203 } 1204 dst = NULL; 1205 } 1206 1207 if (err > 0) 1208 err = np->recverr ? net_xmit_errno(err) : 0; 1209 release_sock(sk); 1210 out: 1211 dst_release(dst); 1212 fl6_sock_release(flowlabel); 1213 if (!err) 1214 return len; 1215 /* 1216 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting 1217 * ENOBUFS might not be good (it's not tunable per se), but otherwise 1218 * we don't have a good statistic (IpOutDiscards but it can be too many 1219 * things). We could add another new stat but at least for now that 1220 * seems like overkill. 1221 */ 1222 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { 1223 UDP6_INC_STATS_USER(sock_net(sk), 1224 UDP_MIB_SNDBUFERRORS, is_udplite); 1225 } 1226 return err; 1227 1228 do_confirm: 1229 dst_confirm(dst); 1230 if (!(msg->msg_flags&MSG_PROBE) || len) 1231 goto back_from_confirm; 1232 err = 0; 1233 goto out; 1234 } 1235 1236 void udpv6_destroy_sock(struct sock *sk) 1237 { 1238 lock_sock(sk); 1239 udp_v6_flush_pending_frames(sk); 1240 release_sock(sk); 1241 1242 inet6_destroy_sock(sk); 1243 } 1244 1245 /* 1246 * Socket option code for UDP 1247 */ 1248 int udpv6_setsockopt(struct sock *sk, int level, int optname, 1249 char __user *optval, unsigned int optlen) 1250 { 1251 if (level == SOL_UDP || level == SOL_UDPLITE) 1252 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1253 udp_v6_push_pending_frames); 1254 return ipv6_setsockopt(sk, level, optname, optval, optlen); 1255 } 1256 1257 #ifdef CONFIG_COMPAT 1258 int compat_udpv6_setsockopt(struct sock *sk, int level, int optname, 1259 char __user *optval, unsigned int optlen) 1260 { 1261 if (level == SOL_UDP || level == SOL_UDPLITE) 1262 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1263 udp_v6_push_pending_frames); 1264 return compat_ipv6_setsockopt(sk, level, optname, optval, optlen); 1265 } 1266 #endif 1267 1268 int udpv6_getsockopt(struct sock *sk, int level, int optname, 1269 char __user *optval, int __user *optlen) 1270 { 1271 if (level == SOL_UDP || level == SOL_UDPLITE) 1272 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1273 return ipv6_getsockopt(sk, level, optname, optval, optlen); 1274 } 1275 1276 #ifdef CONFIG_COMPAT 1277 int compat_udpv6_getsockopt(struct sock *sk, int level, int optname, 1278 char __user *optval, int __user *optlen) 1279 { 1280 if (level == SOL_UDP || level == SOL_UDPLITE) 1281 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1282 return compat_ipv6_getsockopt(sk, level, optname, optval, optlen); 1283 } 1284 #endif 1285 1286 static int udp6_ufo_send_check(struct sk_buff *skb) 1287 { 1288 const struct ipv6hdr *ipv6h; 1289 struct udphdr *uh; 1290 1291 if (!pskb_may_pull(skb, sizeof(*uh))) 1292 return -EINVAL; 1293 1294 ipv6h = ipv6_hdr(skb); 1295 uh = udp_hdr(skb); 1296 1297 uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len, 1298 IPPROTO_UDP, 0); 1299 skb->csum_start = skb_transport_header(skb) - skb->head; 1300 skb->csum_offset = offsetof(struct udphdr, check); 1301 skb->ip_summed = CHECKSUM_PARTIAL; 1302 return 0; 1303 } 1304 1305 static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, 1306 netdev_features_t features) 1307 { 1308 struct sk_buff *segs = ERR_PTR(-EINVAL); 1309 unsigned int mss; 1310 unsigned int unfrag_ip6hlen, unfrag_len; 1311 struct frag_hdr *fptr; 1312 u8 *mac_start, *prevhdr; 1313 u8 nexthdr; 1314 u8 frag_hdr_sz = sizeof(struct frag_hdr); 1315 int offset; 1316 __wsum csum; 1317 1318 mss = skb_shinfo(skb)->gso_size; 1319 if (unlikely(skb->len <= mss)) 1320 goto out; 1321 1322 if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) { 1323 /* Packet is from an untrusted source, reset gso_segs. */ 1324 int type = skb_shinfo(skb)->gso_type; 1325 1326 if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) || 1327 !(type & (SKB_GSO_UDP)))) 1328 goto out; 1329 1330 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss); 1331 1332 segs = NULL; 1333 goto out; 1334 } 1335 1336 /* Do software UFO. Complete and fill in the UDP checksum as HW cannot 1337 * do checksum of UDP packets sent as multiple IP fragments. 1338 */ 1339 offset = skb_checksum_start_offset(skb); 1340 csum = skb_checksum(skb, offset, skb->len- offset, 0); 1341 offset += skb->csum_offset; 1342 *(__sum16 *)(skb->data + offset) = csum_fold(csum); 1343 skb->ip_summed = CHECKSUM_NONE; 1344 1345 /* Check if there is enough headroom to insert fragment header. */ 1346 if ((skb_mac_header(skb) < skb->head + frag_hdr_sz) && 1347 pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC)) 1348 goto out; 1349 1350 /* Find the unfragmentable header and shift it left by frag_hdr_sz 1351 * bytes to insert fragment header. 1352 */ 1353 unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr); 1354 nexthdr = *prevhdr; 1355 *prevhdr = NEXTHDR_FRAGMENT; 1356 unfrag_len = skb_network_header(skb) - skb_mac_header(skb) + 1357 unfrag_ip6hlen; 1358 mac_start = skb_mac_header(skb); 1359 memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len); 1360 1361 skb->mac_header -= frag_hdr_sz; 1362 skb->network_header -= frag_hdr_sz; 1363 1364 fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen); 1365 fptr->nexthdr = nexthdr; 1366 fptr->reserved = 0; 1367 ipv6_select_ident(fptr, (struct rt6_info *)skb_dst(skb)); 1368 1369 /* Fragment the skb. ipv6 header and the remaining fields of the 1370 * fragment header are updated in ipv6_gso_segment() 1371 */ 1372 segs = skb_segment(skb, features); 1373 1374 out: 1375 return segs; 1376 } 1377 1378 static const struct inet6_protocol udpv6_protocol = { 1379 .handler = udpv6_rcv, 1380 .err_handler = udpv6_err, 1381 .gso_send_check = udp6_ufo_send_check, 1382 .gso_segment = udp6_ufo_fragment, 1383 .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, 1384 }; 1385 1386 /* ------------------------------------------------------------------------ */ 1387 #ifdef CONFIG_PROC_FS 1388 1389 static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket) 1390 { 1391 struct inet_sock *inet = inet_sk(sp); 1392 struct ipv6_pinfo *np = inet6_sk(sp); 1393 const struct in6_addr *dest, *src; 1394 __u16 destp, srcp; 1395 1396 dest = &np->daddr; 1397 src = &np->rcv_saddr; 1398 destp = ntohs(inet->inet_dport); 1399 srcp = ntohs(inet->inet_sport); 1400 seq_printf(seq, 1401 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1402 "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d\n", 1403 bucket, 1404 src->s6_addr32[0], src->s6_addr32[1], 1405 src->s6_addr32[2], src->s6_addr32[3], srcp, 1406 dest->s6_addr32[0], dest->s6_addr32[1], 1407 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1408 sp->sk_state, 1409 sk_wmem_alloc_get(sp), 1410 sk_rmem_alloc_get(sp), 1411 0, 0L, 0, 1412 sock_i_uid(sp), 0, 1413 sock_i_ino(sp), 1414 atomic_read(&sp->sk_refcnt), sp, 1415 atomic_read(&sp->sk_drops)); 1416 } 1417 1418 int udp6_seq_show(struct seq_file *seq, void *v) 1419 { 1420 if (v == SEQ_START_TOKEN) 1421 seq_printf(seq, 1422 " sl " 1423 "local_address " 1424 "remote_address " 1425 "st tx_queue rx_queue tr tm->when retrnsmt" 1426 " uid timeout inode ref pointer drops\n"); 1427 else 1428 udp6_sock_seq_show(seq, v, ((struct udp_iter_state *)seq->private)->bucket); 1429 return 0; 1430 } 1431 1432 static const struct file_operations udp6_afinfo_seq_fops = { 1433 .owner = THIS_MODULE, 1434 .open = udp_seq_open, 1435 .read = seq_read, 1436 .llseek = seq_lseek, 1437 .release = seq_release_net 1438 }; 1439 1440 static struct udp_seq_afinfo udp6_seq_afinfo = { 1441 .name = "udp6", 1442 .family = AF_INET6, 1443 .udp_table = &udp_table, 1444 .seq_fops = &udp6_afinfo_seq_fops, 1445 .seq_ops = { 1446 .show = udp6_seq_show, 1447 }, 1448 }; 1449 1450 int __net_init udp6_proc_init(struct net *net) 1451 { 1452 return udp_proc_register(net, &udp6_seq_afinfo); 1453 } 1454 1455 void udp6_proc_exit(struct net *net) { 1456 udp_proc_unregister(net, &udp6_seq_afinfo); 1457 } 1458 #endif /* CONFIG_PROC_FS */ 1459 1460 /* ------------------------------------------------------------------------ */ 1461 1462 struct proto udpv6_prot = { 1463 .name = "UDPv6", 1464 .owner = THIS_MODULE, 1465 .close = udp_lib_close, 1466 .connect = ip6_datagram_connect, 1467 .disconnect = udp_disconnect, 1468 .ioctl = udp_ioctl, 1469 .destroy = udpv6_destroy_sock, 1470 .setsockopt = udpv6_setsockopt, 1471 .getsockopt = udpv6_getsockopt, 1472 .sendmsg = udpv6_sendmsg, 1473 .recvmsg = udpv6_recvmsg, 1474 .backlog_rcv = udpv6_queue_rcv_skb, 1475 .hash = udp_lib_hash, 1476 .unhash = udp_lib_unhash, 1477 .rehash = udp_v6_rehash, 1478 .get_port = udp_v6_get_port, 1479 .memory_allocated = &udp_memory_allocated, 1480 .sysctl_mem = sysctl_udp_mem, 1481 .sysctl_wmem = &sysctl_udp_wmem_min, 1482 .sysctl_rmem = &sysctl_udp_rmem_min, 1483 .obj_size = sizeof(struct udp6_sock), 1484 .slab_flags = SLAB_DESTROY_BY_RCU, 1485 .h.udp_table = &udp_table, 1486 #ifdef CONFIG_COMPAT 1487 .compat_setsockopt = compat_udpv6_setsockopt, 1488 .compat_getsockopt = compat_udpv6_getsockopt, 1489 #endif 1490 .clear_sk = sk_prot_clear_portaddr_nulls, 1491 }; 1492 1493 static struct inet_protosw udpv6_protosw = { 1494 .type = SOCK_DGRAM, 1495 .protocol = IPPROTO_UDP, 1496 .prot = &udpv6_prot, 1497 .ops = &inet6_dgram_ops, 1498 .no_check = UDP_CSUM_DEFAULT, 1499 .flags = INET_PROTOSW_PERMANENT, 1500 }; 1501 1502 1503 int __init udpv6_init(void) 1504 { 1505 int ret; 1506 1507 ret = inet6_add_protocol(&udpv6_protocol, IPPROTO_UDP); 1508 if (ret) 1509 goto out; 1510 1511 ret = inet6_register_protosw(&udpv6_protosw); 1512 if (ret) 1513 goto out_udpv6_protocol; 1514 out: 1515 return ret; 1516 1517 out_udpv6_protocol: 1518 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1519 goto out; 1520 } 1521 1522 void udpv6_exit(void) 1523 { 1524 inet6_unregister_protosw(&udpv6_protosw); 1525 inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP); 1526 } 1527