1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * UDP over IPv6 4 * Linux INET6 implementation 5 * 6 * Authors: 7 * Pedro Roque <roque@di.fc.ul.pt> 8 * 9 * Based on linux/ipv4/udp.c 10 * 11 * Fixes: 12 * Hideaki YOSHIFUJI : sin6_scope_id support 13 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which 14 * Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind 15 * a single port at the same time. 16 * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data 17 * YOSHIFUJI Hideaki @USAGI: convert /proc/net/udp6 to seq_file. 18 */ 19 20 #include <linux/bpf-cgroup.h> 21 #include <linux/errno.h> 22 #include <linux/types.h> 23 #include <linux/socket.h> 24 #include <linux/sockios.h> 25 #include <linux/net.h> 26 #include <linux/in6.h> 27 #include <linux/netdevice.h> 28 #include <linux/if_arp.h> 29 #include <linux/ipv6.h> 30 #include <linux/icmpv6.h> 31 #include <linux/init.h> 32 #include <linux/module.h> 33 #include <linux/skbuff.h> 34 #include <linux/slab.h> 35 #include <linux/uaccess.h> 36 #include <linux/indirect_call_wrapper.h> 37 #include <trace/events/udp.h> 38 39 #include <net/addrconf.h> 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/seg6.h> 46 #include <net/tcp_states.h> 47 #include <net/ip6_checksum.h> 48 #include <net/ip6_tunnel.h> 49 #include <net/xfrm.h> 50 #include <net/inet_hashtables.h> 51 #include <net/inet6_hashtables.h> 52 #include <net/busy_poll.h> 53 #include <net/sock_reuseport.h> 54 #include <net/gro.h> 55 56 #include <linux/proc_fs.h> 57 #include <linux/seq_file.h> 58 #include <trace/events/skb.h> 59 #include "udp_impl.h" 60 61 static void udpv6_destruct_sock(struct sock *sk) 62 { 63 udp_destruct_common(sk); 64 inet6_sock_destruct(sk); 65 } 66 67 int udpv6_init_sock(struct sock *sk) 68 { 69 udp_lib_init_sock(sk); 70 sk->sk_destruct = udpv6_destruct_sock; 71 set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); 72 return 0; 73 } 74 75 INDIRECT_CALLABLE_SCOPE 76 u32 udp6_ehashfn(const struct net *net, 77 const struct in6_addr *laddr, 78 const u16 lport, 79 const struct in6_addr *faddr, 80 const __be16 fport) 81 { 82 u32 lhash, fhash; 83 84 net_get_random_once(&udp6_ehash_secret, 85 sizeof(udp6_ehash_secret)); 86 net_get_random_once(&udp_ipv6_hash_secret, 87 sizeof(udp_ipv6_hash_secret)); 88 89 lhash = (__force u32)laddr->s6_addr32[3]; 90 fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret); 91 92 return __inet6_ehashfn(lhash, lport, fhash, fport, 93 udp6_ehash_secret + net_hash_mix(net)); 94 } 95 96 int udp_v6_get_port(struct sock *sk, unsigned short snum) 97 { 98 unsigned int hash2_nulladdr = 99 ipv6_portaddr_hash(sock_net(sk), &in6addr_any, snum); 100 unsigned int hash2_partial = 101 ipv6_portaddr_hash(sock_net(sk), &sk->sk_v6_rcv_saddr, 0); 102 103 /* precompute partial secondary hash */ 104 udp_sk(sk)->udp_portaddr_hash = hash2_partial; 105 return udp_lib_get_port(sk, snum, hash2_nulladdr); 106 } 107 108 void udp_v6_rehash(struct sock *sk) 109 { 110 u16 new_hash = ipv6_portaddr_hash(sock_net(sk), 111 &sk->sk_v6_rcv_saddr, 112 inet_sk(sk)->inet_num); 113 u16 new_hash4; 114 115 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) { 116 new_hash4 = udp_ehashfn(sock_net(sk), 117 sk->sk_rcv_saddr, sk->sk_num, 118 sk->sk_daddr, sk->sk_dport); 119 } else { 120 new_hash4 = udp6_ehashfn(sock_net(sk), 121 &sk->sk_v6_rcv_saddr, sk->sk_num, 122 &sk->sk_v6_daddr, sk->sk_dport); 123 } 124 125 udp_lib_rehash(sk, new_hash, new_hash4); 126 } 127 128 static int compute_score(struct sock *sk, const struct net *net, 129 const struct in6_addr *saddr, __be16 sport, 130 const struct in6_addr *daddr, unsigned short hnum, 131 int dif, int sdif) 132 { 133 int bound_dev_if, score; 134 struct inet_sock *inet; 135 bool dev_match; 136 137 if (!net_eq(sock_net(sk), net) || 138 udp_sk(sk)->udp_port_hash != hnum || 139 sk->sk_family != PF_INET6) 140 return -1; 141 142 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr)) 143 return -1; 144 145 score = 0; 146 inet = inet_sk(sk); 147 148 if (inet->inet_dport) { 149 if (inet->inet_dport != sport) 150 return -1; 151 score++; 152 } 153 154 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 155 if (!ipv6_addr_equal(&sk->sk_v6_daddr, saddr)) 156 return -1; 157 score++; 158 } 159 160 bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 161 dev_match = udp_sk_bound_dev_eq(net, bound_dev_if, dif, sdif); 162 if (!dev_match) 163 return -1; 164 if (bound_dev_if) 165 score++; 166 167 if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id()) 168 score++; 169 170 return score; 171 } 172 173 /* called with rcu_read_lock() */ 174 static struct sock *udp6_lib_lookup2(const struct net *net, 175 const struct in6_addr *saddr, __be16 sport, 176 const struct in6_addr *daddr, unsigned int hnum, 177 int dif, int sdif, struct udp_hslot *hslot2, 178 struct sk_buff *skb) 179 { 180 struct sock *sk, *result; 181 int score, badness; 182 bool need_rescore; 183 184 result = NULL; 185 badness = -1; 186 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { 187 need_rescore = false; 188 rescore: 189 score = compute_score(need_rescore ? result : sk, net, saddr, 190 sport, daddr, hnum, dif, sdif); 191 if (score > badness) { 192 badness = score; 193 194 if (need_rescore) 195 continue; 196 197 if (sk->sk_state == TCP_ESTABLISHED) { 198 result = sk; 199 continue; 200 } 201 202 result = inet6_lookup_reuseport(net, sk, skb, sizeof(struct udphdr), 203 saddr, sport, daddr, hnum, udp6_ehashfn); 204 if (!result) { 205 result = sk; 206 continue; 207 } 208 209 /* Fall back to scoring if group has connections */ 210 if (!reuseport_has_conns(sk)) 211 return result; 212 213 /* Reuseport logic returned an error, keep original score. */ 214 if (IS_ERR(result)) 215 continue; 216 217 /* compute_score is too long of a function to be 218 * inlined, and calling it again here yields 219 * measureable overhead for some 220 * workloads. Work around it by jumping 221 * backwards to rescore 'result'. 222 */ 223 need_rescore = true; 224 goto rescore; 225 } 226 } 227 return result; 228 } 229 230 #if IS_ENABLED(CONFIG_BASE_SMALL) 231 static struct sock *udp6_lib_lookup4(const struct net *net, 232 const struct in6_addr *saddr, __be16 sport, 233 const struct in6_addr *daddr, 234 unsigned int hnum, int dif, int sdif, 235 struct udp_table *udptable) 236 { 237 return NULL; 238 } 239 240 static void udp6_hash4(struct sock *sk) 241 { 242 } 243 #else /* !CONFIG_BASE_SMALL */ 244 static struct sock *udp6_lib_lookup4(const struct net *net, 245 const struct in6_addr *saddr, __be16 sport, 246 const struct in6_addr *daddr, 247 unsigned int hnum, int dif, int sdif, 248 struct udp_table *udptable) 249 { 250 const __portpair ports = INET_COMBINED_PORTS(sport, hnum); 251 const struct hlist_nulls_node *node; 252 struct udp_hslot *hslot4; 253 unsigned int hash4, slot; 254 struct udp_sock *up; 255 struct sock *sk; 256 257 hash4 = udp6_ehashfn(net, daddr, hnum, saddr, sport); 258 slot = hash4 & udptable->mask; 259 hslot4 = &udptable->hash4[slot]; 260 261 begin: 262 udp_lrpa_for_each_entry_rcu(up, node, &hslot4->nulls_head) { 263 sk = (struct sock *)up; 264 if (inet6_match(net, sk, saddr, daddr, ports, dif, sdif)) 265 return sk; 266 } 267 268 /* if the nulls value we got at the end of this lookup is not the 269 * expected one, we must restart lookup. We probably met an item that 270 * was moved to another chain due to rehash. 271 */ 272 if (get_nulls_value(node) != slot) 273 goto begin; 274 275 return NULL; 276 } 277 278 static void udp6_hash4(struct sock *sk) 279 { 280 struct net *net = sock_net(sk); 281 unsigned int hash; 282 283 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) { 284 udp4_hash4(sk); 285 return; 286 } 287 288 if (sk_unhashed(sk) || ipv6_addr_any(&sk->sk_v6_rcv_saddr)) 289 return; 290 291 hash = udp6_ehashfn(net, &sk->sk_v6_rcv_saddr, sk->sk_num, 292 &sk->sk_v6_daddr, sk->sk_dport); 293 294 udp_lib_hash4(sk, hash); 295 } 296 #endif /* CONFIG_BASE_SMALL */ 297 298 /* rcu_read_lock() must be held */ 299 struct sock *__udp6_lib_lookup(const struct net *net, 300 const struct in6_addr *saddr, __be16 sport, 301 const struct in6_addr *daddr, __be16 dport, 302 int dif, int sdif, struct udp_table *udptable, 303 struct sk_buff *skb) 304 { 305 unsigned short hnum = ntohs(dport); 306 struct udp_hslot *hslot2; 307 struct sock *result, *sk; 308 unsigned int hash2; 309 310 hash2 = ipv6_portaddr_hash(net, daddr, hnum); 311 hslot2 = udp_hashslot2(udptable, hash2); 312 313 if (udp_has_hash4(hslot2)) { 314 result = udp6_lib_lookup4(net, saddr, sport, daddr, hnum, 315 dif, sdif, udptable); 316 if (result) /* udp6_lib_lookup4 return sk or NULL */ 317 return result; 318 } 319 320 /* Lookup connected or non-wildcard sockets */ 321 result = udp6_lib_lookup2(net, saddr, sport, 322 daddr, hnum, dif, sdif, 323 hslot2, skb); 324 if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED) 325 goto done; 326 327 /* Lookup redirect from BPF */ 328 if (static_branch_unlikely(&bpf_sk_lookup_enabled) && 329 udptable == net->ipv4.udp_table) { 330 sk = inet6_lookup_run_sk_lookup(net, IPPROTO_UDP, skb, sizeof(struct udphdr), 331 saddr, sport, daddr, hnum, dif, 332 udp6_ehashfn); 333 if (sk) { 334 result = sk; 335 goto done; 336 } 337 } 338 339 /* Got non-wildcard socket or error on first lookup */ 340 if (result) 341 goto done; 342 343 /* Lookup wildcard sockets */ 344 hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum); 345 hslot2 = udp_hashslot2(udptable, hash2); 346 347 result = udp6_lib_lookup2(net, saddr, sport, 348 &in6addr_any, hnum, dif, sdif, 349 hslot2, skb); 350 done: 351 if (IS_ERR(result)) 352 return NULL; 353 return result; 354 } 355 EXPORT_SYMBOL_GPL(__udp6_lib_lookup); 356 357 static struct sock *__udp6_lib_lookup_skb(struct sk_buff *skb, 358 __be16 sport, __be16 dport, 359 struct udp_table *udptable) 360 { 361 const struct ipv6hdr *iph = ipv6_hdr(skb); 362 363 return __udp6_lib_lookup(dev_net(skb->dev), &iph->saddr, sport, 364 &iph->daddr, dport, inet6_iif(skb), 365 inet6_sdif(skb), udptable, skb); 366 } 367 368 struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb, 369 __be16 sport, __be16 dport) 370 { 371 const u16 offset = NAPI_GRO_CB(skb)->network_offsets[skb->encapsulation]; 372 const struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + offset); 373 struct net *net = dev_net(skb->dev); 374 int iif, sdif; 375 376 inet6_get_iif_sdif(skb, &iif, &sdif); 377 378 return __udp6_lib_lookup(net, &iph->saddr, sport, 379 &iph->daddr, dport, iif, 380 sdif, net->ipv4.udp_table, NULL); 381 } 382 383 /* Must be called under rcu_read_lock(). 384 * Does increment socket refcount. 385 */ 386 #if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6) 387 struct sock *udp6_lib_lookup(const struct net *net, const struct in6_addr *saddr, __be16 sport, 388 const struct in6_addr *daddr, __be16 dport, int dif) 389 { 390 struct sock *sk; 391 392 sk = __udp6_lib_lookup(net, saddr, sport, daddr, dport, 393 dif, 0, net->ipv4.udp_table, NULL); 394 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt)) 395 sk = NULL; 396 return sk; 397 } 398 EXPORT_SYMBOL_GPL(udp6_lib_lookup); 399 #endif 400 401 /* do not use the scratch area len for jumbogram: their length execeeds the 402 * scratch area space; note that the IP6CB flags is still in the first 403 * cacheline, so checking for jumbograms is cheap 404 */ 405 static int udp6_skb_len(struct sk_buff *skb) 406 { 407 return unlikely(inet6_is_jumbogram(skb)) ? skb->len : udp_skb_len(skb); 408 } 409 410 /* 411 * This should be easy, if there is something there we 412 * return it, otherwise we block. 413 */ 414 415 int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 416 int flags, int *addr_len) 417 { 418 struct ipv6_pinfo *np = inet6_sk(sk); 419 struct inet_sock *inet = inet_sk(sk); 420 struct sk_buff *skb; 421 unsigned int ulen, copied; 422 int off, err, peeking = flags & MSG_PEEK; 423 int is_udplite = IS_UDPLITE(sk); 424 struct udp_mib __percpu *mib; 425 bool checksum_valid = false; 426 int is_udp4; 427 428 if (flags & MSG_ERRQUEUE) 429 return ipv6_recv_error(sk, msg, len, addr_len); 430 431 if (np->rxpmtu && np->rxopt.bits.rxpmtu) 432 return ipv6_recv_rxpmtu(sk, msg, len, addr_len); 433 434 try_again: 435 off = sk_peek_offset(sk, flags); 436 skb = __skb_recv_udp(sk, flags, &off, &err); 437 if (!skb) 438 return err; 439 440 ulen = udp6_skb_len(skb); 441 copied = len; 442 if (copied > ulen - off) 443 copied = ulen - off; 444 else if (copied < ulen) 445 msg->msg_flags |= MSG_TRUNC; 446 447 is_udp4 = (skb->protocol == htons(ETH_P_IP)); 448 mib = __UDPX_MIB(sk, is_udp4); 449 450 /* 451 * If checksum is needed at all, try to do it while copying the 452 * data. If the data is truncated, or if we only want a partial 453 * coverage checksum (UDP-Lite), do it before the copy. 454 */ 455 456 if (copied < ulen || peeking || 457 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) { 458 checksum_valid = udp_skb_csum_unnecessary(skb) || 459 !__udp_lib_checksum_complete(skb); 460 if (!checksum_valid) 461 goto csum_copy_err; 462 } 463 464 if (checksum_valid || udp_skb_csum_unnecessary(skb)) { 465 if (udp_skb_is_linear(skb)) 466 err = copy_linear_skb(skb, copied, off, &msg->msg_iter); 467 else 468 err = skb_copy_datagram_msg(skb, off, msg, copied); 469 } else { 470 err = skb_copy_and_csum_datagram_msg(skb, off, msg); 471 if (err == -EINVAL) 472 goto csum_copy_err; 473 } 474 if (unlikely(err)) { 475 if (!peeking) { 476 atomic_inc(&sk->sk_drops); 477 SNMP_INC_STATS(mib, UDP_MIB_INERRORS); 478 } 479 kfree_skb(skb); 480 return err; 481 } 482 if (!peeking) 483 SNMP_INC_STATS(mib, UDP_MIB_INDATAGRAMS); 484 485 sock_recv_cmsgs(msg, sk, skb); 486 487 /* Copy the address. */ 488 if (msg->msg_name) { 489 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 490 sin6->sin6_family = AF_INET6; 491 sin6->sin6_port = udp_hdr(skb)->source; 492 sin6->sin6_flowinfo = 0; 493 494 if (is_udp4) { 495 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 496 &sin6->sin6_addr); 497 sin6->sin6_scope_id = 0; 498 } else { 499 sin6->sin6_addr = ipv6_hdr(skb)->saddr; 500 sin6->sin6_scope_id = 501 ipv6_iface_scope_id(&sin6->sin6_addr, 502 inet6_iif(skb)); 503 } 504 *addr_len = sizeof(*sin6); 505 506 BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, 507 (struct sockaddr *)sin6, 508 addr_len); 509 } 510 511 if (udp_test_bit(GRO_ENABLED, sk)) 512 udp_cmsg_recv(msg, sk, skb); 513 514 if (np->rxopt.all) 515 ip6_datagram_recv_common_ctl(sk, msg, skb); 516 517 if (is_udp4) { 518 if (inet_cmsg_flags(inet)) 519 ip_cmsg_recv_offset(msg, sk, skb, 520 sizeof(struct udphdr), off); 521 } else { 522 if (np->rxopt.all) 523 ip6_datagram_recv_specific_ctl(sk, msg, skb); 524 } 525 526 err = copied; 527 if (flags & MSG_TRUNC) 528 err = ulen; 529 530 skb_consume_udp(sk, skb, peeking ? -err : err); 531 return err; 532 533 csum_copy_err: 534 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags, 535 udp_skb_destructor)) { 536 SNMP_INC_STATS(mib, UDP_MIB_CSUMERRORS); 537 SNMP_INC_STATS(mib, UDP_MIB_INERRORS); 538 } 539 kfree_skb(skb); 540 541 /* starting over for a new packet, but check if we need to yield */ 542 cond_resched(); 543 msg->msg_flags &= ~MSG_TRUNC; 544 goto try_again; 545 } 546 547 DECLARE_STATIC_KEY_FALSE(udpv6_encap_needed_key); 548 void udpv6_encap_enable(void) 549 { 550 static_branch_inc(&udpv6_encap_needed_key); 551 } 552 EXPORT_SYMBOL(udpv6_encap_enable); 553 554 /* Handler for tunnels with arbitrary destination ports: no socket lookup, go 555 * through error handlers in encapsulations looking for a match. 556 */ 557 static int __udp6_lib_err_encap_no_sk(struct sk_buff *skb, 558 struct inet6_skb_parm *opt, 559 u8 type, u8 code, int offset, __be32 info) 560 { 561 int i; 562 563 for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) { 564 int (*handler)(struct sk_buff *skb, struct inet6_skb_parm *opt, 565 u8 type, u8 code, int offset, __be32 info); 566 const struct ip6_tnl_encap_ops *encap; 567 568 encap = rcu_dereference(ip6tun_encaps[i]); 569 if (!encap) 570 continue; 571 handler = encap->err_handler; 572 if (handler && !handler(skb, opt, type, code, offset, info)) 573 return 0; 574 } 575 576 return -ENOENT; 577 } 578 579 /* Try to match ICMP errors to UDP tunnels by looking up a socket without 580 * reversing source and destination port: this will match tunnels that force the 581 * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that 582 * lwtunnels might actually break this assumption by being configured with 583 * different destination ports on endpoints, in this case we won't be able to 584 * trace ICMP messages back to them. 585 * 586 * If this doesn't match any socket, probe tunnels with arbitrary destination 587 * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port 588 * we've sent packets to won't necessarily match the local destination port. 589 * 590 * Then ask the tunnel implementation to match the error against a valid 591 * association. 592 * 593 * Return an error if we can't find a match, the socket if we need further 594 * processing, zero otherwise. 595 */ 596 static struct sock *__udp6_lib_err_encap(struct net *net, 597 const struct ipv6hdr *hdr, int offset, 598 struct udphdr *uh, 599 struct udp_table *udptable, 600 struct sock *sk, 601 struct sk_buff *skb, 602 struct inet6_skb_parm *opt, 603 u8 type, u8 code, __be32 info) 604 { 605 int (*lookup)(struct sock *sk, struct sk_buff *skb); 606 int network_offset, transport_offset; 607 struct udp_sock *up; 608 609 network_offset = skb_network_offset(skb); 610 transport_offset = skb_transport_offset(skb); 611 612 /* Network header needs to point to the outer IPv6 header inside ICMP */ 613 skb_reset_network_header(skb); 614 615 /* Transport header needs to point to the UDP header */ 616 skb_set_transport_header(skb, offset); 617 618 if (sk) { 619 up = udp_sk(sk); 620 621 lookup = READ_ONCE(up->encap_err_lookup); 622 if (lookup && lookup(sk, skb)) 623 sk = NULL; 624 625 goto out; 626 } 627 628 sk = __udp6_lib_lookup(net, &hdr->daddr, uh->source, 629 &hdr->saddr, uh->dest, 630 inet6_iif(skb), 0, udptable, skb); 631 if (sk) { 632 up = udp_sk(sk); 633 634 lookup = READ_ONCE(up->encap_err_lookup); 635 if (!lookup || lookup(sk, skb)) 636 sk = NULL; 637 } 638 639 out: 640 if (!sk) { 641 sk = ERR_PTR(__udp6_lib_err_encap_no_sk(skb, opt, type, code, 642 offset, info)); 643 } 644 645 skb_set_transport_header(skb, transport_offset); 646 skb_set_network_header(skb, network_offset); 647 648 return sk; 649 } 650 651 int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 652 u8 type, u8 code, int offset, __be32 info, 653 struct udp_table *udptable) 654 { 655 struct ipv6_pinfo *np; 656 const struct ipv6hdr *hdr = (const struct ipv6hdr *)skb->data; 657 const struct in6_addr *saddr = &hdr->saddr; 658 const struct in6_addr *daddr = seg6_get_daddr(skb, opt) ? : &hdr->daddr; 659 struct udphdr *uh = (struct udphdr *)(skb->data+offset); 660 bool tunnel = false; 661 struct sock *sk; 662 int harderr; 663 int err; 664 struct net *net = dev_net(skb->dev); 665 666 sk = __udp6_lib_lookup(net, daddr, uh->dest, saddr, uh->source, 667 inet6_iif(skb), inet6_sdif(skb), udptable, NULL); 668 669 if (!sk || READ_ONCE(udp_sk(sk)->encap_type)) { 670 /* No socket for error: try tunnels before discarding */ 671 if (static_branch_unlikely(&udpv6_encap_needed_key)) { 672 sk = __udp6_lib_err_encap(net, hdr, offset, uh, 673 udptable, sk, skb, 674 opt, type, code, info); 675 if (!sk) 676 return 0; 677 } else 678 sk = ERR_PTR(-ENOENT); 679 680 if (IS_ERR(sk)) { 681 __ICMP6_INC_STATS(net, __in6_dev_get(skb->dev), 682 ICMP6_MIB_INERRORS); 683 return PTR_ERR(sk); 684 } 685 686 tunnel = true; 687 } 688 689 harderr = icmpv6_err_convert(type, code, &err); 690 np = inet6_sk(sk); 691 692 if (type == ICMPV6_PKT_TOOBIG) { 693 if (!ip6_sk_accept_pmtu(sk)) 694 goto out; 695 ip6_sk_update_pmtu(skb, sk, info); 696 if (READ_ONCE(np->pmtudisc) != IPV6_PMTUDISC_DONT) 697 harderr = 1; 698 } 699 if (type == NDISC_REDIRECT) { 700 if (tunnel) { 701 ip6_redirect(skb, sock_net(sk), inet6_iif(skb), 702 READ_ONCE(sk->sk_mark), sk->sk_uid); 703 } else { 704 ip6_sk_redirect(skb, sk); 705 } 706 goto out; 707 } 708 709 /* Tunnels don't have an application socket: don't pass errors back */ 710 if (tunnel) { 711 if (udp_sk(sk)->encap_err_rcv) 712 udp_sk(sk)->encap_err_rcv(sk, skb, err, uh->dest, 713 ntohl(info), (u8 *)(uh+1)); 714 goto out; 715 } 716 717 if (!inet6_test_bit(RECVERR6, sk)) { 718 if (!harderr || sk->sk_state != TCP_ESTABLISHED) 719 goto out; 720 } else { 721 ipv6_icmp_error(sk, skb, err, uh->dest, ntohl(info), (u8 *)(uh+1)); 722 } 723 724 sk->sk_err = err; 725 sk_error_report(sk); 726 out: 727 return 0; 728 } 729 730 static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 731 { 732 int rc; 733 734 if (!ipv6_addr_any(&sk->sk_v6_daddr)) { 735 sock_rps_save_rxhash(sk, skb); 736 sk_mark_napi_id(sk, skb); 737 sk_incoming_cpu_update(sk); 738 } else { 739 sk_mark_napi_id_once(sk, skb); 740 } 741 742 rc = __udp_enqueue_schedule_skb(sk, skb); 743 if (rc < 0) { 744 int is_udplite = IS_UDPLITE(sk); 745 enum skb_drop_reason drop_reason; 746 747 /* Note that an ENOMEM error is charged twice */ 748 if (rc == -ENOMEM) { 749 UDP6_INC_STATS(sock_net(sk), 750 UDP_MIB_RCVBUFERRORS, is_udplite); 751 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF; 752 } else { 753 UDP6_INC_STATS(sock_net(sk), 754 UDP_MIB_MEMERRORS, is_udplite); 755 drop_reason = SKB_DROP_REASON_PROTO_MEM; 756 } 757 UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 758 trace_udp_fail_queue_rcv_skb(rc, sk, skb); 759 sk_skb_reason_drop(sk, skb, drop_reason); 760 return -1; 761 } 762 763 return 0; 764 } 765 766 static __inline__ int udpv6_err(struct sk_buff *skb, 767 struct inet6_skb_parm *opt, u8 type, 768 u8 code, int offset, __be32 info) 769 { 770 return __udp6_lib_err(skb, opt, type, code, offset, info, 771 dev_net(skb->dev)->ipv4.udp_table); 772 } 773 774 static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb) 775 { 776 enum skb_drop_reason drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; 777 struct udp_sock *up = udp_sk(sk); 778 int is_udplite = IS_UDPLITE(sk); 779 780 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) { 781 drop_reason = SKB_DROP_REASON_XFRM_POLICY; 782 goto drop; 783 } 784 nf_reset_ct(skb); 785 786 if (static_branch_unlikely(&udpv6_encap_needed_key) && 787 READ_ONCE(up->encap_type)) { 788 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); 789 790 /* 791 * This is an encapsulation socket so pass the skb to 792 * the socket's udp_encap_rcv() hook. Otherwise, just 793 * fall through and pass this up the UDP socket. 794 * up->encap_rcv() returns the following value: 795 * =0 if skb was successfully passed to the encap 796 * handler or was discarded by it. 797 * >0 if skb should be passed on to UDP. 798 * <0 if skb should be resubmitted as proto -N 799 */ 800 801 /* if we're overly short, let UDP handle it */ 802 encap_rcv = READ_ONCE(up->encap_rcv); 803 if (encap_rcv) { 804 int ret; 805 806 /* Verify checksum before giving to encap */ 807 if (udp_lib_checksum_complete(skb)) 808 goto csum_error; 809 810 ret = encap_rcv(sk, skb); 811 if (ret <= 0) { 812 __UDP6_INC_STATS(sock_net(sk), 813 UDP_MIB_INDATAGRAMS, 814 is_udplite); 815 return -ret; 816 } 817 } 818 819 /* FALLTHROUGH -- it's a UDP Packet */ 820 } 821 822 /* 823 * UDP-Lite specific tests, ignored on UDP sockets (see net/ipv4/udp.c). 824 */ 825 if (udp_test_bit(UDPLITE_RECV_CC, sk) && UDP_SKB_CB(skb)->partial_cov) { 826 u16 pcrlen = READ_ONCE(up->pcrlen); 827 828 if (pcrlen == 0) { /* full coverage was set */ 829 net_dbg_ratelimited("UDPLITE6: partial coverage %d while full coverage %d requested\n", 830 UDP_SKB_CB(skb)->cscov, skb->len); 831 goto drop; 832 } 833 if (UDP_SKB_CB(skb)->cscov < pcrlen) { 834 net_dbg_ratelimited("UDPLITE6: coverage %d too small, need min %d\n", 835 UDP_SKB_CB(skb)->cscov, pcrlen); 836 goto drop; 837 } 838 } 839 840 prefetch(&sk->sk_rmem_alloc); 841 if (rcu_access_pointer(sk->sk_filter) && 842 udp_lib_checksum_complete(skb)) 843 goto csum_error; 844 845 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) { 846 drop_reason = SKB_DROP_REASON_SOCKET_FILTER; 847 goto drop; 848 } 849 850 udp_csum_pull_header(skb); 851 852 skb_dst_drop(skb); 853 854 return __udpv6_queue_rcv_skb(sk, skb); 855 856 csum_error: 857 drop_reason = SKB_DROP_REASON_UDP_CSUM; 858 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite); 859 drop: 860 __UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite); 861 atomic_inc(&sk->sk_drops); 862 sk_skb_reason_drop(sk, skb, drop_reason); 863 return -1; 864 } 865 866 static int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 867 { 868 struct sk_buff *next, *segs; 869 int ret; 870 871 if (likely(!udp_unexpected_gso(sk, skb))) 872 return udpv6_queue_rcv_one_skb(sk, skb); 873 874 __skb_push(skb, -skb_mac_offset(skb)); 875 segs = udp_rcv_segment(sk, skb, false); 876 skb_list_walk_safe(segs, skb, next) { 877 __skb_pull(skb, skb_transport_offset(skb)); 878 879 udp_post_segment_fix_csum(skb); 880 ret = udpv6_queue_rcv_one_skb(sk, skb); 881 if (ret > 0) 882 ip6_protocol_deliver_rcu(dev_net(skb->dev), skb, ret, 883 true); 884 } 885 return 0; 886 } 887 888 static bool __udp_v6_is_mcast_sock(struct net *net, const struct sock *sk, 889 __be16 loc_port, const struct in6_addr *loc_addr, 890 __be16 rmt_port, const struct in6_addr *rmt_addr, 891 int dif, int sdif, unsigned short hnum) 892 { 893 const struct inet_sock *inet = inet_sk(sk); 894 895 if (!net_eq(sock_net(sk), net)) 896 return false; 897 898 if (udp_sk(sk)->udp_port_hash != hnum || 899 sk->sk_family != PF_INET6 || 900 (inet->inet_dport && inet->inet_dport != rmt_port) || 901 (!ipv6_addr_any(&sk->sk_v6_daddr) && 902 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) || 903 !udp_sk_bound_dev_eq(net, READ_ONCE(sk->sk_bound_dev_if), dif, sdif) || 904 (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) && 905 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr))) 906 return false; 907 if (!inet6_mc_check(sk, loc_addr, rmt_addr)) 908 return false; 909 return true; 910 } 911 912 static void udp6_csum_zero_error(struct sk_buff *skb) 913 { 914 /* RFC 2460 section 8.1 says that we SHOULD log 915 * this error. Well, it is reasonable. 916 */ 917 net_dbg_ratelimited("IPv6: udp checksum is 0 for [%pI6c]:%u->[%pI6c]:%u\n", 918 &ipv6_hdr(skb)->saddr, ntohs(udp_hdr(skb)->source), 919 &ipv6_hdr(skb)->daddr, ntohs(udp_hdr(skb)->dest)); 920 } 921 922 /* 923 * Note: called only from the BH handler context, 924 * so we don't need to lock the hashes. 925 */ 926 static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb, 927 const struct in6_addr *saddr, const struct in6_addr *daddr, 928 struct udp_table *udptable, int proto) 929 { 930 struct sock *sk, *first = NULL; 931 const struct udphdr *uh = udp_hdr(skb); 932 unsigned short hnum = ntohs(uh->dest); 933 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum); 934 unsigned int offset = offsetof(typeof(*sk), sk_node); 935 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10); 936 int dif = inet6_iif(skb); 937 int sdif = inet6_sdif(skb); 938 struct hlist_node *node; 939 struct sk_buff *nskb; 940 941 if (use_hash2) { 942 hash2_any = ipv6_portaddr_hash(net, &in6addr_any, hnum) & 943 udptable->mask; 944 hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask; 945 start_lookup: 946 hslot = &udptable->hash2[hash2].hslot; 947 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node); 948 } 949 950 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) { 951 if (!__udp_v6_is_mcast_sock(net, sk, uh->dest, daddr, 952 uh->source, saddr, dif, sdif, 953 hnum)) 954 continue; 955 /* If zero checksum and no_check is not on for 956 * the socket then skip it. 957 */ 958 if (!uh->check && !udp_get_no_check6_rx(sk)) 959 continue; 960 if (!first) { 961 first = sk; 962 continue; 963 } 964 nskb = skb_clone(skb, GFP_ATOMIC); 965 if (unlikely(!nskb)) { 966 atomic_inc(&sk->sk_drops); 967 __UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS, 968 IS_UDPLITE(sk)); 969 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, 970 IS_UDPLITE(sk)); 971 continue; 972 } 973 974 if (udpv6_queue_rcv_skb(sk, nskb) > 0) 975 consume_skb(nskb); 976 } 977 978 /* Also lookup *:port if we are using hash2 and haven't done so yet. */ 979 if (use_hash2 && hash2 != hash2_any) { 980 hash2 = hash2_any; 981 goto start_lookup; 982 } 983 984 if (first) { 985 if (udpv6_queue_rcv_skb(first, skb) > 0) 986 consume_skb(skb); 987 } else { 988 kfree_skb(skb); 989 __UDP6_INC_STATS(net, UDP_MIB_IGNOREDMULTI, 990 proto == IPPROTO_UDPLITE); 991 } 992 return 0; 993 } 994 995 static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst) 996 { 997 if (udp_sk_rx_dst_set(sk, dst)) 998 sk->sk_rx_dst_cookie = rt6_get_cookie(dst_rt6_info(dst)); 999 } 1000 1001 /* wrapper for udp_queue_rcv_skb tacking care of csum conversion and 1002 * return code conversion for ip layer consumption 1003 */ 1004 static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb, 1005 struct udphdr *uh) 1006 { 1007 int ret; 1008 1009 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk)) 1010 skb_checksum_try_convert(skb, IPPROTO_UDP, ip6_compute_pseudo); 1011 1012 ret = udpv6_queue_rcv_skb(sk, skb); 1013 1014 /* a return value > 0 means to resubmit the input */ 1015 if (ret > 0) 1016 return ret; 1017 return 0; 1018 } 1019 1020 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, 1021 int proto) 1022 { 1023 enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED; 1024 const struct in6_addr *saddr, *daddr; 1025 struct net *net = dev_net(skb->dev); 1026 struct sock *sk = NULL; 1027 struct udphdr *uh; 1028 bool refcounted; 1029 u32 ulen = 0; 1030 1031 if (!pskb_may_pull(skb, sizeof(struct udphdr))) 1032 goto discard; 1033 1034 saddr = &ipv6_hdr(skb)->saddr; 1035 daddr = &ipv6_hdr(skb)->daddr; 1036 uh = udp_hdr(skb); 1037 1038 ulen = ntohs(uh->len); 1039 if (ulen > skb->len) 1040 goto short_packet; 1041 1042 if (proto == IPPROTO_UDP) { 1043 /* UDP validates ulen. */ 1044 1045 /* Check for jumbo payload */ 1046 if (ulen == 0) 1047 ulen = skb->len; 1048 1049 if (ulen < sizeof(*uh)) 1050 goto short_packet; 1051 1052 if (ulen < skb->len) { 1053 if (pskb_trim_rcsum(skb, ulen)) 1054 goto short_packet; 1055 saddr = &ipv6_hdr(skb)->saddr; 1056 daddr = &ipv6_hdr(skb)->daddr; 1057 uh = udp_hdr(skb); 1058 } 1059 } 1060 1061 if (udp6_csum_init(skb, uh, proto)) 1062 goto csum_error; 1063 1064 /* Check if the socket is already available, e.g. due to early demux */ 1065 sk = inet6_steal_sock(net, skb, sizeof(struct udphdr), saddr, uh->source, daddr, uh->dest, 1066 &refcounted, udp6_ehashfn); 1067 if (IS_ERR(sk)) 1068 goto no_sk; 1069 1070 if (sk) { 1071 struct dst_entry *dst = skb_dst(skb); 1072 int ret; 1073 1074 if (unlikely(rcu_dereference(sk->sk_rx_dst) != dst)) 1075 udp6_sk_rx_dst_set(sk, dst); 1076 1077 if (!uh->check && !udp_get_no_check6_rx(sk)) { 1078 if (refcounted) 1079 sock_put(sk); 1080 goto report_csum_error; 1081 } 1082 1083 ret = udp6_unicast_rcv_skb(sk, skb, uh); 1084 if (refcounted) 1085 sock_put(sk); 1086 return ret; 1087 } 1088 1089 /* 1090 * Multicast receive code 1091 */ 1092 if (ipv6_addr_is_multicast(daddr)) 1093 return __udp6_lib_mcast_deliver(net, skb, 1094 saddr, daddr, udptable, proto); 1095 1096 /* Unicast */ 1097 sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable); 1098 if (sk) { 1099 if (!uh->check && !udp_get_no_check6_rx(sk)) 1100 goto report_csum_error; 1101 return udp6_unicast_rcv_skb(sk, skb, uh); 1102 } 1103 no_sk: 1104 reason = SKB_DROP_REASON_NO_SOCKET; 1105 1106 if (!uh->check) 1107 goto report_csum_error; 1108 1109 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) 1110 goto discard; 1111 nf_reset_ct(skb); 1112 1113 if (udp_lib_checksum_complete(skb)) 1114 goto csum_error; 1115 1116 __UDP6_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE); 1117 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); 1118 1119 sk_skb_reason_drop(sk, skb, reason); 1120 return 0; 1121 1122 short_packet: 1123 if (reason == SKB_DROP_REASON_NOT_SPECIFIED) 1124 reason = SKB_DROP_REASON_PKT_TOO_SMALL; 1125 net_dbg_ratelimited("UDP%sv6: short packet: From [%pI6c]:%u %d/%d to [%pI6c]:%u\n", 1126 proto == IPPROTO_UDPLITE ? "-Lite" : "", 1127 saddr, ntohs(uh->source), 1128 ulen, skb->len, 1129 daddr, ntohs(uh->dest)); 1130 goto discard; 1131 1132 report_csum_error: 1133 udp6_csum_zero_error(skb); 1134 csum_error: 1135 if (reason == SKB_DROP_REASON_NOT_SPECIFIED) 1136 reason = SKB_DROP_REASON_UDP_CSUM; 1137 __UDP6_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE); 1138 discard: 1139 __UDP6_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); 1140 sk_skb_reason_drop(sk, skb, reason); 1141 return 0; 1142 } 1143 1144 1145 static struct sock *__udp6_lib_demux_lookup(struct net *net, 1146 __be16 loc_port, const struct in6_addr *loc_addr, 1147 __be16 rmt_port, const struct in6_addr *rmt_addr, 1148 int dif, int sdif) 1149 { 1150 struct udp_table *udptable = net->ipv4.udp_table; 1151 unsigned short hnum = ntohs(loc_port); 1152 struct udp_hslot *hslot2; 1153 unsigned int hash2; 1154 __portpair ports; 1155 struct sock *sk; 1156 1157 hash2 = ipv6_portaddr_hash(net, loc_addr, hnum); 1158 hslot2 = udp_hashslot2(udptable, hash2); 1159 ports = INET_COMBINED_PORTS(rmt_port, hnum); 1160 1161 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) { 1162 if (sk->sk_state == TCP_ESTABLISHED && 1163 inet6_match(net, sk, rmt_addr, loc_addr, ports, dif, sdif)) 1164 return sk; 1165 /* Only check first socket in chain */ 1166 break; 1167 } 1168 return NULL; 1169 } 1170 1171 void udp_v6_early_demux(struct sk_buff *skb) 1172 { 1173 struct net *net = dev_net(skb->dev); 1174 const struct udphdr *uh; 1175 struct sock *sk; 1176 struct dst_entry *dst; 1177 int dif = skb->dev->ifindex; 1178 int sdif = inet6_sdif(skb); 1179 1180 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 1181 sizeof(struct udphdr))) 1182 return; 1183 1184 uh = udp_hdr(skb); 1185 1186 if (skb->pkt_type == PACKET_HOST) 1187 sk = __udp6_lib_demux_lookup(net, uh->dest, 1188 &ipv6_hdr(skb)->daddr, 1189 uh->source, &ipv6_hdr(skb)->saddr, 1190 dif, sdif); 1191 else 1192 return; 1193 1194 if (!sk) 1195 return; 1196 1197 skb->sk = sk; 1198 DEBUG_NET_WARN_ON_ONCE(sk_is_refcounted(sk)); 1199 skb->destructor = sock_pfree; 1200 dst = rcu_dereference(sk->sk_rx_dst); 1201 1202 if (dst) 1203 dst = dst_check(dst, sk->sk_rx_dst_cookie); 1204 if (dst) { 1205 /* set noref for now. 1206 * any place which wants to hold dst has to call 1207 * dst_hold_safe() 1208 */ 1209 skb_dst_set_noref(skb, dst); 1210 } 1211 } 1212 1213 INDIRECT_CALLABLE_SCOPE int udpv6_rcv(struct sk_buff *skb) 1214 { 1215 return __udp6_lib_rcv(skb, dev_net(skb->dev)->ipv4.udp_table, IPPROTO_UDP); 1216 } 1217 1218 /* 1219 * Throw away all pending data and cancel the corking. Socket is locked. 1220 */ 1221 static void udp_v6_flush_pending_frames(struct sock *sk) 1222 { 1223 struct udp_sock *up = udp_sk(sk); 1224 1225 if (up->pending == AF_INET) 1226 udp_flush_pending_frames(sk); 1227 else if (up->pending) { 1228 up->len = 0; 1229 WRITE_ONCE(up->pending, 0); 1230 ip6_flush_pending_frames(sk); 1231 } 1232 } 1233 1234 static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr, 1235 int addr_len) 1236 { 1237 if (addr_len < offsetofend(struct sockaddr, sa_family)) 1238 return -EINVAL; 1239 /* The following checks are replicated from __ip6_datagram_connect() 1240 * and intended to prevent BPF program called below from accessing 1241 * bytes that are out of the bound specified by user in addr_len. 1242 */ 1243 if (uaddr->sa_family == AF_INET) { 1244 if (ipv6_only_sock(sk)) 1245 return -EAFNOSUPPORT; 1246 return udp_pre_connect(sk, uaddr, addr_len); 1247 } 1248 1249 if (addr_len < SIN6_LEN_RFC2133) 1250 return -EINVAL; 1251 1252 return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr, &addr_len); 1253 } 1254 1255 static int udpv6_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) 1256 { 1257 int res; 1258 1259 lock_sock(sk); 1260 res = __ip6_datagram_connect(sk, uaddr, addr_len); 1261 if (!res) 1262 udp6_hash4(sk); 1263 release_sock(sk); 1264 return res; 1265 } 1266 1267 /** 1268 * udp6_hwcsum_outgoing - handle outgoing HW checksumming 1269 * @sk: socket we are sending on 1270 * @skb: sk_buff containing the filled-in UDP header 1271 * (checksum field must be zeroed out) 1272 * @saddr: source address 1273 * @daddr: destination address 1274 * @len: length of packet 1275 */ 1276 static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, 1277 const struct in6_addr *saddr, 1278 const struct in6_addr *daddr, int len) 1279 { 1280 unsigned int offset; 1281 struct udphdr *uh = udp_hdr(skb); 1282 struct sk_buff *frags = skb_shinfo(skb)->frag_list; 1283 __wsum csum = 0; 1284 1285 if (!frags) { 1286 /* Only one fragment on the socket. */ 1287 skb->csum_start = skb_transport_header(skb) - skb->head; 1288 skb->csum_offset = offsetof(struct udphdr, check); 1289 uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0); 1290 } else { 1291 /* 1292 * HW-checksum won't work as there are two or more 1293 * fragments on the socket so that all csums of sk_buffs 1294 * should be together 1295 */ 1296 offset = skb_transport_offset(skb); 1297 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); 1298 csum = skb->csum; 1299 1300 skb->ip_summed = CHECKSUM_NONE; 1301 1302 do { 1303 csum = csum_add(csum, frags->csum); 1304 } while ((frags = frags->next)); 1305 1306 uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 1307 csum); 1308 if (uh->check == 0) 1309 uh->check = CSUM_MANGLED_0; 1310 } 1311 } 1312 1313 /* 1314 * Sending 1315 */ 1316 1317 static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6, 1318 struct inet_cork *cork) 1319 { 1320 struct sock *sk = skb->sk; 1321 struct udphdr *uh; 1322 int err = 0; 1323 int is_udplite = IS_UDPLITE(sk); 1324 __wsum csum = 0; 1325 int offset = skb_transport_offset(skb); 1326 int len = skb->len - offset; 1327 int datalen = len - sizeof(*uh); 1328 1329 /* 1330 * Create a UDP header 1331 */ 1332 uh = udp_hdr(skb); 1333 uh->source = fl6->fl6_sport; 1334 uh->dest = fl6->fl6_dport; 1335 uh->len = htons(len); 1336 uh->check = 0; 1337 1338 if (cork->gso_size) { 1339 const int hlen = skb_network_header_len(skb) + 1340 sizeof(struct udphdr); 1341 1342 if (hlen + cork->gso_size > cork->fragsize) { 1343 kfree_skb(skb); 1344 return -EINVAL; 1345 } 1346 if (datalen > cork->gso_size * UDP_MAX_SEGMENTS) { 1347 kfree_skb(skb); 1348 return -EINVAL; 1349 } 1350 if (udp_get_no_check6_tx(sk)) { 1351 kfree_skb(skb); 1352 return -EINVAL; 1353 } 1354 if (is_udplite || dst_xfrm(skb_dst(skb))) { 1355 kfree_skb(skb); 1356 return -EIO; 1357 } 1358 1359 if (datalen > cork->gso_size) { 1360 skb_shinfo(skb)->gso_size = cork->gso_size; 1361 skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4; 1362 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen, 1363 cork->gso_size); 1364 1365 /* Don't checksum the payload, skb will get segmented */ 1366 goto csum_partial; 1367 } 1368 } 1369 1370 if (is_udplite) 1371 csum = udplite_csum(skb); 1372 else if (udp_get_no_check6_tx(sk)) { /* UDP csum disabled */ 1373 skb->ip_summed = CHECKSUM_NONE; 1374 goto send; 1375 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ 1376 csum_partial: 1377 udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len); 1378 goto send; 1379 } else 1380 csum = udp_csum(skb); 1381 1382 /* add protocol-dependent pseudo-header */ 1383 uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr, 1384 len, fl6->flowi6_proto, csum); 1385 if (uh->check == 0) 1386 uh->check = CSUM_MANGLED_0; 1387 1388 send: 1389 err = ip6_send_skb(skb); 1390 if (err) { 1391 if (err == -ENOBUFS && !inet6_test_bit(RECVERR6, sk)) { 1392 UDP6_INC_STATS(sock_net(sk), 1393 UDP_MIB_SNDBUFERRORS, is_udplite); 1394 err = 0; 1395 } 1396 } else { 1397 UDP6_INC_STATS(sock_net(sk), 1398 UDP_MIB_OUTDATAGRAMS, is_udplite); 1399 } 1400 return err; 1401 } 1402 1403 static int udp_v6_push_pending_frames(struct sock *sk) 1404 { 1405 struct sk_buff *skb; 1406 struct udp_sock *up = udp_sk(sk); 1407 int err = 0; 1408 1409 if (up->pending == AF_INET) 1410 return udp_push_pending_frames(sk); 1411 1412 skb = ip6_finish_skb(sk); 1413 if (!skb) 1414 goto out; 1415 1416 err = udp_v6_send_skb(skb, &inet_sk(sk)->cork.fl.u.ip6, 1417 &inet_sk(sk)->cork.base); 1418 out: 1419 up->len = 0; 1420 WRITE_ONCE(up->pending, 0); 1421 return err; 1422 } 1423 1424 int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 1425 { 1426 struct ipv6_txoptions opt_space; 1427 struct udp_sock *up = udp_sk(sk); 1428 struct inet_sock *inet = inet_sk(sk); 1429 struct ipv6_pinfo *np = inet6_sk(sk); 1430 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 1431 struct in6_addr *daddr, *final_p, final; 1432 struct ipv6_txoptions *opt = NULL; 1433 struct ipv6_txoptions *opt_to_free = NULL; 1434 struct ip6_flowlabel *flowlabel = NULL; 1435 struct inet_cork_full cork; 1436 struct flowi6 *fl6 = &cork.fl.u.ip6; 1437 struct dst_entry *dst; 1438 struct ipcm6_cookie ipc6; 1439 int addr_len = msg->msg_namelen; 1440 bool connected = false; 1441 int ulen = len; 1442 int corkreq = udp_test_bit(CORK, sk) || msg->msg_flags & MSG_MORE; 1443 int err; 1444 int is_udplite = IS_UDPLITE(sk); 1445 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); 1446 1447 ipcm6_init(&ipc6); 1448 ipc6.gso_size = READ_ONCE(up->gso_size); 1449 ipc6.sockc.tsflags = READ_ONCE(sk->sk_tsflags); 1450 ipc6.sockc.mark = READ_ONCE(sk->sk_mark); 1451 1452 /* destination address check */ 1453 if (sin6) { 1454 if (addr_len < offsetof(struct sockaddr, sa_data)) 1455 return -EINVAL; 1456 1457 switch (sin6->sin6_family) { 1458 case AF_INET6: 1459 if (addr_len < SIN6_LEN_RFC2133) 1460 return -EINVAL; 1461 daddr = &sin6->sin6_addr; 1462 if (ipv6_addr_any(daddr) && 1463 ipv6_addr_v4mapped(&np->saddr)) 1464 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK), 1465 daddr); 1466 break; 1467 case AF_INET: 1468 goto do_udp_sendmsg; 1469 case AF_UNSPEC: 1470 msg->msg_name = sin6 = NULL; 1471 msg->msg_namelen = addr_len = 0; 1472 daddr = NULL; 1473 break; 1474 default: 1475 return -EINVAL; 1476 } 1477 } else if (!READ_ONCE(up->pending)) { 1478 if (sk->sk_state != TCP_ESTABLISHED) 1479 return -EDESTADDRREQ; 1480 daddr = &sk->sk_v6_daddr; 1481 } else 1482 daddr = NULL; 1483 1484 if (daddr) { 1485 if (ipv6_addr_v4mapped(daddr)) { 1486 struct sockaddr_in sin; 1487 sin.sin_family = AF_INET; 1488 sin.sin_port = sin6 ? sin6->sin6_port : inet->inet_dport; 1489 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 1490 msg->msg_name = &sin; 1491 msg->msg_namelen = sizeof(sin); 1492 do_udp_sendmsg: 1493 err = ipv6_only_sock(sk) ? 1494 -ENETUNREACH : udp_sendmsg(sk, msg, len); 1495 msg->msg_name = sin6; 1496 msg->msg_namelen = addr_len; 1497 return err; 1498 } 1499 } 1500 1501 /* Rough check on arithmetic overflow, 1502 better check is made in ip6_append_data(). 1503 */ 1504 if (len > INT_MAX - sizeof(struct udphdr)) 1505 return -EMSGSIZE; 1506 1507 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; 1508 if (READ_ONCE(up->pending)) { 1509 if (READ_ONCE(up->pending) == AF_INET) 1510 return udp_sendmsg(sk, msg, len); 1511 /* 1512 * There are pending frames. 1513 * The socket lock must be held while it's corked. 1514 */ 1515 lock_sock(sk); 1516 if (likely(up->pending)) { 1517 if (unlikely(up->pending != AF_INET6)) { 1518 release_sock(sk); 1519 return -EAFNOSUPPORT; 1520 } 1521 dst = NULL; 1522 goto do_append_data; 1523 } 1524 release_sock(sk); 1525 } 1526 ulen += sizeof(struct udphdr); 1527 1528 memset(fl6, 0, sizeof(*fl6)); 1529 1530 if (sin6) { 1531 if (sin6->sin6_port == 0) 1532 return -EINVAL; 1533 1534 fl6->fl6_dport = sin6->sin6_port; 1535 daddr = &sin6->sin6_addr; 1536 1537 if (inet6_test_bit(SNDFLOW, sk)) { 1538 fl6->flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK; 1539 if (fl6->flowlabel & IPV6_FLOWLABEL_MASK) { 1540 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel); 1541 if (IS_ERR(flowlabel)) 1542 return -EINVAL; 1543 } 1544 } 1545 1546 /* 1547 * Otherwise it will be difficult to maintain 1548 * sk->sk_dst_cache. 1549 */ 1550 if (sk->sk_state == TCP_ESTABLISHED && 1551 ipv6_addr_equal(daddr, &sk->sk_v6_daddr)) 1552 daddr = &sk->sk_v6_daddr; 1553 1554 if (addr_len >= sizeof(struct sockaddr_in6) && 1555 sin6->sin6_scope_id && 1556 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr))) 1557 fl6->flowi6_oif = sin6->sin6_scope_id; 1558 } else { 1559 if (sk->sk_state != TCP_ESTABLISHED) 1560 return -EDESTADDRREQ; 1561 1562 fl6->fl6_dport = inet->inet_dport; 1563 daddr = &sk->sk_v6_daddr; 1564 fl6->flowlabel = np->flow_label; 1565 connected = true; 1566 } 1567 1568 if (!fl6->flowi6_oif) 1569 fl6->flowi6_oif = READ_ONCE(sk->sk_bound_dev_if); 1570 1571 if (!fl6->flowi6_oif) 1572 fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; 1573 1574 fl6->flowi6_uid = sk->sk_uid; 1575 1576 if (msg->msg_controllen) { 1577 opt = &opt_space; 1578 memset(opt, 0, sizeof(struct ipv6_txoptions)); 1579 opt->tot_len = sizeof(*opt); 1580 ipc6.opt = opt; 1581 1582 err = udp_cmsg_send(sk, msg, &ipc6.gso_size); 1583 if (err > 0) { 1584 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, fl6, 1585 &ipc6); 1586 connected = false; 1587 } 1588 if (err < 0) { 1589 fl6_sock_release(flowlabel); 1590 return err; 1591 } 1592 if ((fl6->flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) { 1593 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel); 1594 if (IS_ERR(flowlabel)) 1595 return -EINVAL; 1596 } 1597 if (!(opt->opt_nflen|opt->opt_flen)) 1598 opt = NULL; 1599 } 1600 if (!opt) { 1601 opt = txopt_get(np); 1602 opt_to_free = opt; 1603 } 1604 if (flowlabel) 1605 opt = fl6_merge_options(&opt_space, flowlabel, opt); 1606 opt = ipv6_fixup_options(&opt_space, opt); 1607 ipc6.opt = opt; 1608 1609 fl6->flowi6_proto = sk->sk_protocol; 1610 fl6->flowi6_mark = ipc6.sockc.mark; 1611 fl6->daddr = *daddr; 1612 if (ipv6_addr_any(&fl6->saddr) && !ipv6_addr_any(&np->saddr)) 1613 fl6->saddr = np->saddr; 1614 fl6->fl6_sport = inet->inet_sport; 1615 1616 if (cgroup_bpf_enabled(CGROUP_UDP6_SENDMSG) && !connected) { 1617 err = BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, 1618 (struct sockaddr *)sin6, 1619 &addr_len, 1620 &fl6->saddr); 1621 if (err) 1622 goto out_no_dst; 1623 if (sin6) { 1624 if (ipv6_addr_v4mapped(&sin6->sin6_addr)) { 1625 /* BPF program rewrote IPv6-only by IPv4-mapped 1626 * IPv6. It's currently unsupported. 1627 */ 1628 err = -ENOTSUPP; 1629 goto out_no_dst; 1630 } 1631 if (sin6->sin6_port == 0) { 1632 /* BPF program set invalid port. Reject it. */ 1633 err = -EINVAL; 1634 goto out_no_dst; 1635 } 1636 fl6->fl6_dport = sin6->sin6_port; 1637 fl6->daddr = sin6->sin6_addr; 1638 } 1639 } 1640 1641 if (ipv6_addr_any(&fl6->daddr)) 1642 fl6->daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */ 1643 1644 final_p = fl6_update_dst(fl6, opt, &final); 1645 if (final_p) 1646 connected = false; 1647 1648 if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr)) { 1649 fl6->flowi6_oif = READ_ONCE(np->mcast_oif); 1650 connected = false; 1651 } else if (!fl6->flowi6_oif) 1652 fl6->flowi6_oif = READ_ONCE(np->ucast_oif); 1653 1654 security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6)); 1655 1656 if (ipc6.tclass < 0) 1657 ipc6.tclass = np->tclass; 1658 1659 fl6->flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6->flowlabel); 1660 1661 dst = ip6_sk_dst_lookup_flow(sk, fl6, final_p, connected); 1662 if (IS_ERR(dst)) { 1663 err = PTR_ERR(dst); 1664 dst = NULL; 1665 goto out; 1666 } 1667 1668 if (ipc6.hlimit < 0) 1669 ipc6.hlimit = ip6_sk_dst_hoplimit(np, fl6, dst); 1670 1671 if (msg->msg_flags&MSG_CONFIRM) 1672 goto do_confirm; 1673 back_from_confirm: 1674 1675 /* Lockless fast path for the non-corking case */ 1676 if (!corkreq) { 1677 struct sk_buff *skb; 1678 1679 skb = ip6_make_skb(sk, getfrag, msg, ulen, 1680 sizeof(struct udphdr), &ipc6, 1681 dst_rt6_info(dst), 1682 msg->msg_flags, &cork); 1683 err = PTR_ERR(skb); 1684 if (!IS_ERR_OR_NULL(skb)) 1685 err = udp_v6_send_skb(skb, fl6, &cork.base); 1686 /* ip6_make_skb steals dst reference */ 1687 goto out_no_dst; 1688 } 1689 1690 lock_sock(sk); 1691 if (unlikely(up->pending)) { 1692 /* The socket is already corked while preparing it. */ 1693 /* ... which is an evident application bug. --ANK */ 1694 release_sock(sk); 1695 1696 net_dbg_ratelimited("udp cork app bug 2\n"); 1697 err = -EINVAL; 1698 goto out; 1699 } 1700 1701 WRITE_ONCE(up->pending, AF_INET6); 1702 1703 do_append_data: 1704 if (ipc6.dontfrag < 0) 1705 ipc6.dontfrag = inet6_test_bit(DONTFRAG, sk); 1706 up->len += ulen; 1707 err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr), 1708 &ipc6, fl6, dst_rt6_info(dst), 1709 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags); 1710 if (err) 1711 udp_v6_flush_pending_frames(sk); 1712 else if (!corkreq) 1713 err = udp_v6_push_pending_frames(sk); 1714 else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) 1715 WRITE_ONCE(up->pending, 0); 1716 1717 if (err > 0) 1718 err = inet6_test_bit(RECVERR6, sk) ? net_xmit_errno(err) : 0; 1719 release_sock(sk); 1720 1721 out: 1722 dst_release(dst); 1723 out_no_dst: 1724 fl6_sock_release(flowlabel); 1725 txopt_put(opt_to_free); 1726 if (!err) 1727 return len; 1728 /* 1729 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting 1730 * ENOBUFS might not be good (it's not tunable per se), but otherwise 1731 * we don't have a good statistic (IpOutDiscards but it can be too many 1732 * things). We could add another new stat but at least for now that 1733 * seems like overkill. 1734 */ 1735 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { 1736 UDP6_INC_STATS(sock_net(sk), 1737 UDP_MIB_SNDBUFERRORS, is_udplite); 1738 } 1739 return err; 1740 1741 do_confirm: 1742 if (msg->msg_flags & MSG_PROBE) 1743 dst_confirm_neigh(dst, &fl6->daddr); 1744 if (!(msg->msg_flags&MSG_PROBE) || len) 1745 goto back_from_confirm; 1746 err = 0; 1747 goto out; 1748 } 1749 EXPORT_SYMBOL(udpv6_sendmsg); 1750 1751 static void udpv6_splice_eof(struct socket *sock) 1752 { 1753 struct sock *sk = sock->sk; 1754 struct udp_sock *up = udp_sk(sk); 1755 1756 if (!READ_ONCE(up->pending) || udp_test_bit(CORK, sk)) 1757 return; 1758 1759 lock_sock(sk); 1760 if (up->pending && !udp_test_bit(CORK, sk)) 1761 udp_v6_push_pending_frames(sk); 1762 release_sock(sk); 1763 } 1764 1765 void udpv6_destroy_sock(struct sock *sk) 1766 { 1767 struct udp_sock *up = udp_sk(sk); 1768 lock_sock(sk); 1769 1770 /* protects from races with udp_abort() */ 1771 sock_set_flag(sk, SOCK_DEAD); 1772 udp_v6_flush_pending_frames(sk); 1773 release_sock(sk); 1774 1775 if (static_branch_unlikely(&udpv6_encap_needed_key)) { 1776 if (up->encap_type) { 1777 void (*encap_destroy)(struct sock *sk); 1778 encap_destroy = READ_ONCE(up->encap_destroy); 1779 if (encap_destroy) 1780 encap_destroy(sk); 1781 } 1782 if (udp_test_bit(ENCAP_ENABLED, sk)) { 1783 static_branch_dec(&udpv6_encap_needed_key); 1784 udp_encap_disable(); 1785 } 1786 } 1787 } 1788 1789 /* 1790 * Socket option code for UDP 1791 */ 1792 int udpv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, 1793 unsigned int optlen) 1794 { 1795 if (level == SOL_UDP || level == SOL_UDPLITE || level == SOL_SOCKET) 1796 return udp_lib_setsockopt(sk, level, optname, 1797 optval, optlen, 1798 udp_v6_push_pending_frames); 1799 return ipv6_setsockopt(sk, level, optname, optval, optlen); 1800 } 1801 1802 int udpv6_getsockopt(struct sock *sk, int level, int optname, 1803 char __user *optval, int __user *optlen) 1804 { 1805 if (level == SOL_UDP || level == SOL_UDPLITE) 1806 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1807 return ipv6_getsockopt(sk, level, optname, optval, optlen); 1808 } 1809 1810 1811 /* ------------------------------------------------------------------------ */ 1812 #ifdef CONFIG_PROC_FS 1813 int udp6_seq_show(struct seq_file *seq, void *v) 1814 { 1815 if (v == SEQ_START_TOKEN) { 1816 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER); 1817 } else { 1818 int bucket = ((struct udp_iter_state *)seq->private)->bucket; 1819 const struct inet_sock *inet = inet_sk((const struct sock *)v); 1820 __u16 srcp = ntohs(inet->inet_sport); 1821 __u16 destp = ntohs(inet->inet_dport); 1822 __ip6_dgram_sock_seq_show(seq, v, srcp, destp, 1823 udp_rqueue_get(v), bucket); 1824 } 1825 return 0; 1826 } 1827 1828 const struct seq_operations udp6_seq_ops = { 1829 .start = udp_seq_start, 1830 .next = udp_seq_next, 1831 .stop = udp_seq_stop, 1832 .show = udp6_seq_show, 1833 }; 1834 EXPORT_SYMBOL(udp6_seq_ops); 1835 1836 static struct udp_seq_afinfo udp6_seq_afinfo = { 1837 .family = AF_INET6, 1838 .udp_table = NULL, 1839 }; 1840 1841 int __net_init udp6_proc_init(struct net *net) 1842 { 1843 if (!proc_create_net_data("udp6", 0444, net->proc_net, &udp6_seq_ops, 1844 sizeof(struct udp_iter_state), &udp6_seq_afinfo)) 1845 return -ENOMEM; 1846 return 0; 1847 } 1848 1849 void udp6_proc_exit(struct net *net) 1850 { 1851 remove_proc_entry("udp6", net->proc_net); 1852 } 1853 #endif /* CONFIG_PROC_FS */ 1854 1855 /* ------------------------------------------------------------------------ */ 1856 1857 struct proto udpv6_prot = { 1858 .name = "UDPv6", 1859 .owner = THIS_MODULE, 1860 .close = udp_lib_close, 1861 .pre_connect = udpv6_pre_connect, 1862 .connect = udpv6_connect, 1863 .disconnect = udp_disconnect, 1864 .ioctl = udp_ioctl, 1865 .init = udpv6_init_sock, 1866 .destroy = udpv6_destroy_sock, 1867 .setsockopt = udpv6_setsockopt, 1868 .getsockopt = udpv6_getsockopt, 1869 .sendmsg = udpv6_sendmsg, 1870 .recvmsg = udpv6_recvmsg, 1871 .splice_eof = udpv6_splice_eof, 1872 .release_cb = ip6_datagram_release_cb, 1873 .hash = udp_lib_hash, 1874 .unhash = udp_lib_unhash, 1875 .rehash = udp_v6_rehash, 1876 .get_port = udp_v6_get_port, 1877 .put_port = udp_lib_unhash, 1878 #ifdef CONFIG_BPF_SYSCALL 1879 .psock_update_sk_prot = udp_bpf_update_proto, 1880 #endif 1881 1882 .memory_allocated = &udp_memory_allocated, 1883 .per_cpu_fw_alloc = &udp_memory_per_cpu_fw_alloc, 1884 1885 .sysctl_mem = sysctl_udp_mem, 1886 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min), 1887 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min), 1888 .obj_size = sizeof(struct udp6_sock), 1889 .ipv6_pinfo_offset = offsetof(struct udp6_sock, inet6), 1890 .h.udp_table = NULL, 1891 .diag_destroy = udp_abort, 1892 }; 1893 1894 static struct inet_protosw udpv6_protosw = { 1895 .type = SOCK_DGRAM, 1896 .protocol = IPPROTO_UDP, 1897 .prot = &udpv6_prot, 1898 .ops = &inet6_dgram_ops, 1899 .flags = INET_PROTOSW_PERMANENT, 1900 }; 1901 1902 int __init udpv6_init(void) 1903 { 1904 int ret; 1905 1906 net_hotdata.udpv6_protocol = (struct inet6_protocol) { 1907 .handler = udpv6_rcv, 1908 .err_handler = udpv6_err, 1909 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, 1910 }; 1911 ret = inet6_add_protocol(&net_hotdata.udpv6_protocol, IPPROTO_UDP); 1912 if (ret) 1913 goto out; 1914 1915 ret = inet6_register_protosw(&udpv6_protosw); 1916 if (ret) 1917 goto out_udpv6_protocol; 1918 out: 1919 return ret; 1920 1921 out_udpv6_protocol: 1922 inet6_del_protocol(&net_hotdata.udpv6_protocol, IPPROTO_UDP); 1923 goto out; 1924 } 1925 1926 void udpv6_exit(void) 1927 { 1928 inet6_unregister_protosw(&udpv6_protosw); 1929 inet6_del_protocol(&net_hotdata.udpv6_protocol, IPPROTO_UDP); 1930 } 1931