1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2013 Nicira, Inc. 4 */ 5 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/types.h> 9 #include <linux/kernel.h> 10 #include <linux/skbuff.h> 11 #include <linux/netdevice.h> 12 #include <linux/in.h> 13 #include <linux/if_arp.h> 14 #include <linux/init.h> 15 #include <linux/in6.h> 16 #include <linux/inetdevice.h> 17 #include <linux/netfilter_ipv4.h> 18 #include <linux/etherdevice.h> 19 #include <linux/if_ether.h> 20 #include <linux/if_vlan.h> 21 #include <linux/static_key.h> 22 23 #include <net/ip.h> 24 #include <net/icmp.h> 25 #include <net/protocol.h> 26 #include <net/ip_tunnels.h> 27 #include <net/ip6_tunnel.h> 28 #include <net/ip6_checksum.h> 29 #include <net/arp.h> 30 #include <net/checksum.h> 31 #include <net/dsfield.h> 32 #include <net/inet_ecn.h> 33 #include <net/xfrm.h> 34 #include <net/net_namespace.h> 35 #include <net/netns/generic.h> 36 #include <net/rtnetlink.h> 37 #include <net/dst_metadata.h> 38 #include <net/geneve.h> 39 #include <net/vxlan.h> 40 #include <net/erspan.h> 41 42 const struct ip_tunnel_encap_ops __rcu * 43 iptun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; 44 EXPORT_SYMBOL(iptun_encaps); 45 46 const struct ip6_tnl_encap_ops __rcu * 47 ip6tun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; 48 EXPORT_SYMBOL(ip6tun_encaps); 49 50 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, 51 __be32 src, __be32 dst, __u8 proto, 52 __u8 tos, __u8 ttl, __be16 df, bool xnet) 53 { 54 int pkt_len = skb->len - skb_inner_network_offset(skb); 55 struct net *net = dev_net(rt->dst.dev); 56 struct net_device *dev = skb->dev; 57 struct iphdr *iph; 58 int err; 59 60 skb_scrub_packet(skb, xnet); 61 62 skb_clear_hash_if_not_l4(skb); 63 skb_dst_set(skb, &rt->dst); 64 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 65 66 /* Push down and install the IP header. */ 67 skb_push(skb, sizeof(struct iphdr)); 68 skb_reset_network_header(skb); 69 70 iph = ip_hdr(skb); 71 72 iph->version = 4; 73 iph->ihl = sizeof(struct iphdr) >> 2; 74 iph->frag_off = ip_mtu_locked(&rt->dst) ? 0 : df; 75 iph->protocol = proto; 76 iph->tos = tos; 77 iph->daddr = dst; 78 iph->saddr = src; 79 iph->ttl = ttl; 80 __ip_select_ident(net, iph, skb_shinfo(skb)->gso_segs ?: 1); 81 82 err = ip_local_out(net, sk, skb); 83 84 if (dev) { 85 if (unlikely(net_xmit_eval(err))) 86 pkt_len = 0; 87 iptunnel_xmit_stats(dev, pkt_len); 88 } 89 } 90 EXPORT_SYMBOL_GPL(iptunnel_xmit); 91 92 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len, 93 __be16 inner_proto, bool raw_proto, bool xnet) 94 { 95 if (unlikely(!pskb_may_pull(skb, hdr_len))) 96 return -ENOMEM; 97 98 skb_pull_rcsum(skb, hdr_len); 99 100 if (!raw_proto && inner_proto == htons(ETH_P_TEB)) { 101 struct ethhdr *eh; 102 103 if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) 104 return -ENOMEM; 105 106 eh = (struct ethhdr *)skb->data; 107 if (likely(eth_proto_is_802_3(eh->h_proto))) 108 skb->protocol = eh->h_proto; 109 else 110 skb->protocol = htons(ETH_P_802_2); 111 112 } else { 113 skb->protocol = inner_proto; 114 } 115 116 skb_clear_hash_if_not_l4(skb); 117 __vlan_hwaccel_clear_tag(skb); 118 skb_set_queue_mapping(skb, 0); 119 skb_scrub_packet(skb, xnet); 120 121 return iptunnel_pull_offloads(skb); 122 } 123 EXPORT_SYMBOL_GPL(__iptunnel_pull_header); 124 125 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md, 126 gfp_t flags) 127 { 128 struct metadata_dst *res; 129 struct ip_tunnel_info *dst, *src; 130 131 if (!md || md->type != METADATA_IP_TUNNEL || 132 md->u.tun_info.mode & IP_TUNNEL_INFO_TX) 133 return NULL; 134 135 src = &md->u.tun_info; 136 res = metadata_dst_alloc(src->options_len, METADATA_IP_TUNNEL, flags); 137 if (!res) 138 return NULL; 139 140 dst = &res->u.tun_info; 141 dst->key.tun_id = src->key.tun_id; 142 if (src->mode & IP_TUNNEL_INFO_IPV6) 143 memcpy(&dst->key.u.ipv6.dst, &src->key.u.ipv6.src, 144 sizeof(struct in6_addr)); 145 else 146 dst->key.u.ipv4.dst = src->key.u.ipv4.src; 147 dst->key.tun_flags = src->key.tun_flags; 148 dst->mode = src->mode | IP_TUNNEL_INFO_TX; 149 ip_tunnel_info_opts_set(dst, ip_tunnel_info_opts(src), 150 src->options_len, 0); 151 152 return res; 153 } 154 EXPORT_SYMBOL_GPL(iptunnel_metadata_reply); 155 156 int iptunnel_handle_offloads(struct sk_buff *skb, 157 int gso_type_mask) 158 { 159 int err; 160 161 if (likely(!skb->encapsulation)) { 162 skb_reset_inner_headers(skb); 163 skb->encapsulation = 1; 164 } 165 166 if (skb_is_gso(skb)) { 167 err = skb_header_unclone(skb, GFP_ATOMIC); 168 if (unlikely(err)) 169 return err; 170 skb_shinfo(skb)->gso_type |= gso_type_mask; 171 return 0; 172 } 173 174 if (skb->ip_summed != CHECKSUM_PARTIAL) { 175 skb->ip_summed = CHECKSUM_NONE; 176 /* We clear encapsulation here to prevent badly-written 177 * drivers potentially deciding to offload an inner checksum 178 * if we set CHECKSUM_PARTIAL on the outer header. 179 * This should go away when the drivers are all fixed. 180 */ 181 skb->encapsulation = 0; 182 } 183 184 return 0; 185 } 186 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); 187 188 /** 189 * iptunnel_pmtud_build_icmp() - Build ICMP error message for PMTUD 190 * @skb: Original packet with L2 header 191 * @mtu: MTU value for ICMP error 192 * 193 * Return: length on success, negative error code if message couldn't be built. 194 */ 195 static int iptunnel_pmtud_build_icmp(struct sk_buff *skb, int mtu) 196 { 197 const struct iphdr *iph = ip_hdr(skb); 198 struct icmphdr *icmph; 199 struct iphdr *niph; 200 struct ethhdr eh; 201 int len, err; 202 203 if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct iphdr))) 204 return -EINVAL; 205 206 skb_copy_bits(skb, skb_mac_offset(skb), &eh, ETH_HLEN); 207 pskb_pull(skb, ETH_HLEN); 208 skb_reset_network_header(skb); 209 210 err = pskb_trim(skb, 576 - sizeof(*niph) - sizeof(*icmph)); 211 if (err) 212 return err; 213 214 len = skb->len + sizeof(*icmph); 215 err = skb_cow(skb, sizeof(*niph) + sizeof(*icmph) + ETH_HLEN); 216 if (err) 217 return err; 218 219 icmph = skb_push(skb, sizeof(*icmph)); 220 *icmph = (struct icmphdr) { 221 .type = ICMP_DEST_UNREACH, 222 .code = ICMP_FRAG_NEEDED, 223 .checksum = 0, 224 .un.frag.__unused = 0, 225 .un.frag.mtu = ntohs(mtu), 226 }; 227 icmph->checksum = ip_compute_csum(icmph, len); 228 skb_reset_transport_header(skb); 229 230 niph = skb_push(skb, sizeof(*niph)); 231 *niph = (struct iphdr) { 232 .ihl = sizeof(*niph) / 4u, 233 .version = 4, 234 .tos = 0, 235 .tot_len = htons(len + sizeof(*niph)), 236 .id = 0, 237 .frag_off = htons(IP_DF), 238 .ttl = iph->ttl, 239 .protocol = IPPROTO_ICMP, 240 .saddr = iph->daddr, 241 .daddr = iph->saddr, 242 }; 243 ip_send_check(niph); 244 skb_reset_network_header(skb); 245 246 skb->ip_summed = CHECKSUM_NONE; 247 248 eth_header(skb, skb->dev, htons(eh.h_proto), eh.h_source, eh.h_dest, 0); 249 skb_reset_mac_header(skb); 250 251 return skb->len; 252 } 253 254 /** 255 * iptunnel_pmtud_check_icmp() - Trigger ICMP reply if needed and allowed 256 * @skb: Buffer being sent by encapsulation, L2 headers expected 257 * @mtu: Network MTU for path 258 * 259 * Return: 0 for no ICMP reply, length if built, negative value on error. 260 */ 261 static int iptunnel_pmtud_check_icmp(struct sk_buff *skb, int mtu) 262 { 263 const struct icmphdr *icmph = icmp_hdr(skb); 264 const struct iphdr *iph = ip_hdr(skb); 265 266 if (mtu < 576 || iph->frag_off != htons(IP_DF)) 267 return 0; 268 269 if (ipv4_is_lbcast(iph->daddr) || ipv4_is_multicast(iph->daddr) || 270 ipv4_is_zeronet(iph->saddr) || ipv4_is_loopback(iph->saddr) || 271 ipv4_is_lbcast(iph->saddr) || ipv4_is_multicast(iph->saddr)) 272 return 0; 273 274 if (iph->protocol == IPPROTO_ICMP && icmp_is_err(icmph->type)) 275 return 0; 276 277 return iptunnel_pmtud_build_icmp(skb, mtu); 278 } 279 280 #if IS_ENABLED(CONFIG_IPV6) 281 /** 282 * iptunnel_pmtud_build_icmpv6() - Build ICMPv6 error message for PMTUD 283 * @skb: Original packet with L2 header 284 * @mtu: MTU value for ICMPv6 error 285 * 286 * Return: length on success, negative error code if message couldn't be built. 287 */ 288 static int iptunnel_pmtud_build_icmpv6(struct sk_buff *skb, int mtu) 289 { 290 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 291 struct icmp6hdr *icmp6h; 292 struct ipv6hdr *nip6h; 293 struct ethhdr eh; 294 int len, err; 295 __wsum csum; 296 297 if (!pskb_may_pull(skb, ETH_HLEN + sizeof(struct ipv6hdr))) 298 return -EINVAL; 299 300 skb_copy_bits(skb, skb_mac_offset(skb), &eh, ETH_HLEN); 301 pskb_pull(skb, ETH_HLEN); 302 skb_reset_network_header(skb); 303 304 err = pskb_trim(skb, IPV6_MIN_MTU - sizeof(*nip6h) - sizeof(*icmp6h)); 305 if (err) 306 return err; 307 308 len = skb->len + sizeof(*icmp6h); 309 err = skb_cow(skb, sizeof(*nip6h) + sizeof(*icmp6h) + ETH_HLEN); 310 if (err) 311 return err; 312 313 icmp6h = skb_push(skb, sizeof(*icmp6h)); 314 *icmp6h = (struct icmp6hdr) { 315 .icmp6_type = ICMPV6_PKT_TOOBIG, 316 .icmp6_code = 0, 317 .icmp6_cksum = 0, 318 .icmp6_mtu = htonl(mtu), 319 }; 320 skb_reset_transport_header(skb); 321 322 nip6h = skb_push(skb, sizeof(*nip6h)); 323 *nip6h = (struct ipv6hdr) { 324 .priority = 0, 325 .version = 6, 326 .flow_lbl = { 0 }, 327 .payload_len = htons(len), 328 .nexthdr = IPPROTO_ICMPV6, 329 .hop_limit = ip6h->hop_limit, 330 .saddr = ip6h->daddr, 331 .daddr = ip6h->saddr, 332 }; 333 skb_reset_network_header(skb); 334 335 csum = csum_partial(icmp6h, len, 0); 336 icmp6h->icmp6_cksum = csum_ipv6_magic(&nip6h->saddr, &nip6h->daddr, len, 337 IPPROTO_ICMPV6, csum); 338 339 skb->ip_summed = CHECKSUM_NONE; 340 341 eth_header(skb, skb->dev, htons(eh.h_proto), eh.h_source, eh.h_dest, 0); 342 skb_reset_mac_header(skb); 343 344 return skb->len; 345 } 346 347 /** 348 * iptunnel_pmtud_check_icmpv6() - Trigger ICMPv6 reply if needed and allowed 349 * @skb: Buffer being sent by encapsulation, L2 headers expected 350 * @mtu: Network MTU for path 351 * 352 * Return: 0 for no ICMPv6 reply, length if built, negative value on error. 353 */ 354 static int iptunnel_pmtud_check_icmpv6(struct sk_buff *skb, int mtu) 355 { 356 const struct ipv6hdr *ip6h = ipv6_hdr(skb); 357 int stype = ipv6_addr_type(&ip6h->saddr); 358 u8 proto = ip6h->nexthdr; 359 __be16 frag_off; 360 int offset; 361 362 if (mtu < IPV6_MIN_MTU) 363 return 0; 364 365 if (stype == IPV6_ADDR_ANY || stype == IPV6_ADDR_MULTICAST || 366 stype == IPV6_ADDR_LOOPBACK) 367 return 0; 368 369 offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &proto, 370 &frag_off); 371 if (offset < 0 || (frag_off & htons(~0x7))) 372 return 0; 373 374 if (proto == IPPROTO_ICMPV6) { 375 struct icmp6hdr *icmp6h; 376 377 if (!pskb_may_pull(skb, skb_network_header(skb) + 378 offset + 1 - skb->data)) 379 return 0; 380 381 icmp6h = (struct icmp6hdr *)(skb_network_header(skb) + offset); 382 if (icmpv6_is_err(icmp6h->icmp6_type) || 383 icmp6h->icmp6_type == NDISC_REDIRECT) 384 return 0; 385 } 386 387 return iptunnel_pmtud_build_icmpv6(skb, mtu); 388 } 389 #endif /* IS_ENABLED(CONFIG_IPV6) */ 390 391 /** 392 * skb_tunnel_check_pmtu() - Check, update PMTU and trigger ICMP reply as needed 393 * @skb: Buffer being sent by encapsulation, L2 headers expected 394 * @encap_dst: Destination for tunnel encapsulation (outer IP) 395 * @headroom: Encapsulation header size, bytes 396 * @reply: Build matching ICMP or ICMPv6 message as a result 397 * 398 * L2 tunnel implementations that can carry IP and can be directly bridged 399 * (currently UDP tunnels) can't always rely on IP forwarding paths to handle 400 * PMTU discovery. In the bridged case, ICMP or ICMPv6 messages need to be built 401 * based on payload and sent back by the encapsulation itself. 402 * 403 * For routable interfaces, we just need to update the PMTU for the destination. 404 * 405 * Return: 0 if ICMP error not needed, length if built, negative value on error 406 */ 407 int skb_tunnel_check_pmtu(struct sk_buff *skb, struct dst_entry *encap_dst, 408 int headroom, bool reply) 409 { 410 u32 mtu = dst_mtu(encap_dst) - headroom; 411 412 if ((skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu)) || 413 (!skb_is_gso(skb) && (skb->len - skb_mac_header_len(skb)) <= mtu)) 414 return 0; 415 416 skb_dst_update_pmtu_no_confirm(skb, mtu); 417 418 if (!reply || skb->pkt_type == PACKET_HOST) 419 return 0; 420 421 if (skb->protocol == htons(ETH_P_IP)) 422 return iptunnel_pmtud_check_icmp(skb, mtu); 423 424 #if IS_ENABLED(CONFIG_IPV6) 425 if (skb->protocol == htons(ETH_P_IPV6)) 426 return iptunnel_pmtud_check_icmpv6(skb, mtu); 427 #endif 428 return 0; 429 } 430 EXPORT_SYMBOL(skb_tunnel_check_pmtu); 431 432 static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = { 433 [LWTUNNEL_IP_UNSPEC] = { .strict_start_type = LWTUNNEL_IP_OPTS }, 434 [LWTUNNEL_IP_ID] = { .type = NLA_U64 }, 435 [LWTUNNEL_IP_DST] = { .type = NLA_U32 }, 436 [LWTUNNEL_IP_SRC] = { .type = NLA_U32 }, 437 [LWTUNNEL_IP_TTL] = { .type = NLA_U8 }, 438 [LWTUNNEL_IP_TOS] = { .type = NLA_U8 }, 439 [LWTUNNEL_IP_FLAGS] = { .type = NLA_U16 }, 440 [LWTUNNEL_IP_OPTS] = { .type = NLA_NESTED }, 441 }; 442 443 static const struct nla_policy ip_opts_policy[LWTUNNEL_IP_OPTS_MAX + 1] = { 444 [LWTUNNEL_IP_OPTS_GENEVE] = { .type = NLA_NESTED }, 445 [LWTUNNEL_IP_OPTS_VXLAN] = { .type = NLA_NESTED }, 446 [LWTUNNEL_IP_OPTS_ERSPAN] = { .type = NLA_NESTED }, 447 }; 448 449 static const struct nla_policy 450 geneve_opt_policy[LWTUNNEL_IP_OPT_GENEVE_MAX + 1] = { 451 [LWTUNNEL_IP_OPT_GENEVE_CLASS] = { .type = NLA_U16 }, 452 [LWTUNNEL_IP_OPT_GENEVE_TYPE] = { .type = NLA_U8 }, 453 [LWTUNNEL_IP_OPT_GENEVE_DATA] = { .type = NLA_BINARY, .len = 128 }, 454 }; 455 456 static const struct nla_policy 457 vxlan_opt_policy[LWTUNNEL_IP_OPT_VXLAN_MAX + 1] = { 458 [LWTUNNEL_IP_OPT_VXLAN_GBP] = { .type = NLA_U32 }, 459 }; 460 461 static const struct nla_policy 462 erspan_opt_policy[LWTUNNEL_IP_OPT_ERSPAN_MAX + 1] = { 463 [LWTUNNEL_IP_OPT_ERSPAN_VER] = { .type = NLA_U8 }, 464 [LWTUNNEL_IP_OPT_ERSPAN_INDEX] = { .type = NLA_U32 }, 465 [LWTUNNEL_IP_OPT_ERSPAN_DIR] = { .type = NLA_U8 }, 466 [LWTUNNEL_IP_OPT_ERSPAN_HWID] = { .type = NLA_U8 }, 467 }; 468 469 static int ip_tun_parse_opts_geneve(struct nlattr *attr, 470 struct ip_tunnel_info *info, int opts_len, 471 struct netlink_ext_ack *extack) 472 { 473 struct nlattr *tb[LWTUNNEL_IP_OPT_GENEVE_MAX + 1]; 474 int data_len, err; 475 476 err = nla_parse_nested(tb, LWTUNNEL_IP_OPT_GENEVE_MAX, attr, 477 geneve_opt_policy, extack); 478 if (err) 479 return err; 480 481 if (!tb[LWTUNNEL_IP_OPT_GENEVE_CLASS] || 482 !tb[LWTUNNEL_IP_OPT_GENEVE_TYPE] || 483 !tb[LWTUNNEL_IP_OPT_GENEVE_DATA]) 484 return -EINVAL; 485 486 attr = tb[LWTUNNEL_IP_OPT_GENEVE_DATA]; 487 data_len = nla_len(attr); 488 if (data_len % 4) 489 return -EINVAL; 490 491 if (info) { 492 struct geneve_opt *opt = ip_tunnel_info_opts(info) + opts_len; 493 494 memcpy(opt->opt_data, nla_data(attr), data_len); 495 opt->length = data_len / 4; 496 attr = tb[LWTUNNEL_IP_OPT_GENEVE_CLASS]; 497 opt->opt_class = nla_get_be16(attr); 498 attr = tb[LWTUNNEL_IP_OPT_GENEVE_TYPE]; 499 opt->type = nla_get_u8(attr); 500 info->key.tun_flags |= TUNNEL_GENEVE_OPT; 501 } 502 503 return sizeof(struct geneve_opt) + data_len; 504 } 505 506 static int ip_tun_parse_opts_vxlan(struct nlattr *attr, 507 struct ip_tunnel_info *info, int opts_len, 508 struct netlink_ext_ack *extack) 509 { 510 struct nlattr *tb[LWTUNNEL_IP_OPT_VXLAN_MAX + 1]; 511 int err; 512 513 err = nla_parse_nested(tb, LWTUNNEL_IP_OPT_VXLAN_MAX, attr, 514 vxlan_opt_policy, extack); 515 if (err) 516 return err; 517 518 if (!tb[LWTUNNEL_IP_OPT_VXLAN_GBP]) 519 return -EINVAL; 520 521 if (info) { 522 struct vxlan_metadata *md = 523 ip_tunnel_info_opts(info) + opts_len; 524 525 attr = tb[LWTUNNEL_IP_OPT_VXLAN_GBP]; 526 md->gbp = nla_get_u32(attr); 527 md->gbp &= VXLAN_GBP_MASK; 528 info->key.tun_flags |= TUNNEL_VXLAN_OPT; 529 } 530 531 return sizeof(struct vxlan_metadata); 532 } 533 534 static int ip_tun_parse_opts_erspan(struct nlattr *attr, 535 struct ip_tunnel_info *info, int opts_len, 536 struct netlink_ext_ack *extack) 537 { 538 struct nlattr *tb[LWTUNNEL_IP_OPT_ERSPAN_MAX + 1]; 539 int err; 540 u8 ver; 541 542 err = nla_parse_nested(tb, LWTUNNEL_IP_OPT_ERSPAN_MAX, attr, 543 erspan_opt_policy, extack); 544 if (err) 545 return err; 546 547 if (!tb[LWTUNNEL_IP_OPT_ERSPAN_VER]) 548 return -EINVAL; 549 550 ver = nla_get_u8(tb[LWTUNNEL_IP_OPT_ERSPAN_VER]); 551 if (ver == 1) { 552 if (!tb[LWTUNNEL_IP_OPT_ERSPAN_INDEX]) 553 return -EINVAL; 554 } else if (ver == 2) { 555 if (!tb[LWTUNNEL_IP_OPT_ERSPAN_DIR] || 556 !tb[LWTUNNEL_IP_OPT_ERSPAN_HWID]) 557 return -EINVAL; 558 } else { 559 return -EINVAL; 560 } 561 562 if (info) { 563 struct erspan_metadata *md = 564 ip_tunnel_info_opts(info) + opts_len; 565 566 md->version = ver; 567 if (ver == 1) { 568 attr = tb[LWTUNNEL_IP_OPT_ERSPAN_INDEX]; 569 md->u.index = nla_get_be32(attr); 570 } else { 571 attr = tb[LWTUNNEL_IP_OPT_ERSPAN_DIR]; 572 md->u.md2.dir = nla_get_u8(attr); 573 attr = tb[LWTUNNEL_IP_OPT_ERSPAN_HWID]; 574 set_hwid(&md->u.md2, nla_get_u8(attr)); 575 } 576 577 info->key.tun_flags |= TUNNEL_ERSPAN_OPT; 578 } 579 580 return sizeof(struct erspan_metadata); 581 } 582 583 static int ip_tun_parse_opts(struct nlattr *attr, struct ip_tunnel_info *info, 584 struct netlink_ext_ack *extack) 585 { 586 int err, rem, opt_len, opts_len = 0, type = 0; 587 struct nlattr *nla; 588 589 if (!attr) 590 return 0; 591 592 err = nla_validate(nla_data(attr), nla_len(attr), LWTUNNEL_IP_OPTS_MAX, 593 ip_opts_policy, extack); 594 if (err) 595 return err; 596 597 nla_for_each_attr(nla, nla_data(attr), nla_len(attr), rem) { 598 switch (nla_type(nla)) { 599 case LWTUNNEL_IP_OPTS_GENEVE: 600 if (type && type != TUNNEL_GENEVE_OPT) 601 return -EINVAL; 602 opt_len = ip_tun_parse_opts_geneve(nla, info, opts_len, 603 extack); 604 if (opt_len < 0) 605 return opt_len; 606 opts_len += opt_len; 607 if (opts_len > IP_TUNNEL_OPTS_MAX) 608 return -EINVAL; 609 type = TUNNEL_GENEVE_OPT; 610 break; 611 case LWTUNNEL_IP_OPTS_VXLAN: 612 if (type) 613 return -EINVAL; 614 opt_len = ip_tun_parse_opts_vxlan(nla, info, opts_len, 615 extack); 616 if (opt_len < 0) 617 return opt_len; 618 opts_len += opt_len; 619 type = TUNNEL_VXLAN_OPT; 620 break; 621 case LWTUNNEL_IP_OPTS_ERSPAN: 622 if (type) 623 return -EINVAL; 624 opt_len = ip_tun_parse_opts_erspan(nla, info, opts_len, 625 extack); 626 if (opt_len < 0) 627 return opt_len; 628 opts_len += opt_len; 629 type = TUNNEL_ERSPAN_OPT; 630 break; 631 default: 632 return -EINVAL; 633 } 634 } 635 636 return opts_len; 637 } 638 639 static int ip_tun_get_optlen(struct nlattr *attr, 640 struct netlink_ext_ack *extack) 641 { 642 return ip_tun_parse_opts(attr, NULL, extack); 643 } 644 645 static int ip_tun_set_opts(struct nlattr *attr, struct ip_tunnel_info *info, 646 struct netlink_ext_ack *extack) 647 { 648 return ip_tun_parse_opts(attr, info, extack); 649 } 650 651 static int ip_tun_build_state(struct net *net, struct nlattr *attr, 652 unsigned int family, const void *cfg, 653 struct lwtunnel_state **ts, 654 struct netlink_ext_ack *extack) 655 { 656 struct nlattr *tb[LWTUNNEL_IP_MAX + 1]; 657 struct lwtunnel_state *new_state; 658 struct ip_tunnel_info *tun_info; 659 int err, opt_len; 660 661 err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_MAX, attr, 662 ip_tun_policy, extack); 663 if (err < 0) 664 return err; 665 666 opt_len = ip_tun_get_optlen(tb[LWTUNNEL_IP_OPTS], extack); 667 if (opt_len < 0) 668 return opt_len; 669 670 new_state = lwtunnel_state_alloc(sizeof(*tun_info) + opt_len); 671 if (!new_state) 672 return -ENOMEM; 673 674 new_state->type = LWTUNNEL_ENCAP_IP; 675 676 tun_info = lwt_tun_info(new_state); 677 678 err = ip_tun_set_opts(tb[LWTUNNEL_IP_OPTS], tun_info, extack); 679 if (err < 0) { 680 lwtstate_free(new_state); 681 return err; 682 } 683 684 #ifdef CONFIG_DST_CACHE 685 err = dst_cache_init(&tun_info->dst_cache, GFP_KERNEL); 686 if (err) { 687 lwtstate_free(new_state); 688 return err; 689 } 690 #endif 691 692 if (tb[LWTUNNEL_IP_ID]) 693 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP_ID]); 694 695 if (tb[LWTUNNEL_IP_DST]) 696 tun_info->key.u.ipv4.dst = nla_get_in_addr(tb[LWTUNNEL_IP_DST]); 697 698 if (tb[LWTUNNEL_IP_SRC]) 699 tun_info->key.u.ipv4.src = nla_get_in_addr(tb[LWTUNNEL_IP_SRC]); 700 701 if (tb[LWTUNNEL_IP_TTL]) 702 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]); 703 704 if (tb[LWTUNNEL_IP_TOS]) 705 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]); 706 707 if (tb[LWTUNNEL_IP_FLAGS]) 708 tun_info->key.tun_flags |= 709 (nla_get_be16(tb[LWTUNNEL_IP_FLAGS]) & 710 ~TUNNEL_OPTIONS_PRESENT); 711 712 tun_info->mode = IP_TUNNEL_INFO_TX; 713 tun_info->options_len = opt_len; 714 715 *ts = new_state; 716 717 return 0; 718 } 719 720 static void ip_tun_destroy_state(struct lwtunnel_state *lwtstate) 721 { 722 #ifdef CONFIG_DST_CACHE 723 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 724 725 dst_cache_destroy(&tun_info->dst_cache); 726 #endif 727 } 728 729 static int ip_tun_fill_encap_opts_geneve(struct sk_buff *skb, 730 struct ip_tunnel_info *tun_info) 731 { 732 struct geneve_opt *opt; 733 struct nlattr *nest; 734 int offset = 0; 735 736 nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_GENEVE); 737 if (!nest) 738 return -ENOMEM; 739 740 while (tun_info->options_len > offset) { 741 opt = ip_tunnel_info_opts(tun_info) + offset; 742 if (nla_put_be16(skb, LWTUNNEL_IP_OPT_GENEVE_CLASS, 743 opt->opt_class) || 744 nla_put_u8(skb, LWTUNNEL_IP_OPT_GENEVE_TYPE, opt->type) || 745 nla_put(skb, LWTUNNEL_IP_OPT_GENEVE_DATA, opt->length * 4, 746 opt->opt_data)) { 747 nla_nest_cancel(skb, nest); 748 return -ENOMEM; 749 } 750 offset += sizeof(*opt) + opt->length * 4; 751 } 752 753 nla_nest_end(skb, nest); 754 return 0; 755 } 756 757 static int ip_tun_fill_encap_opts_vxlan(struct sk_buff *skb, 758 struct ip_tunnel_info *tun_info) 759 { 760 struct vxlan_metadata *md; 761 struct nlattr *nest; 762 763 nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_VXLAN); 764 if (!nest) 765 return -ENOMEM; 766 767 md = ip_tunnel_info_opts(tun_info); 768 if (nla_put_u32(skb, LWTUNNEL_IP_OPT_VXLAN_GBP, md->gbp)) { 769 nla_nest_cancel(skb, nest); 770 return -ENOMEM; 771 } 772 773 nla_nest_end(skb, nest); 774 return 0; 775 } 776 777 static int ip_tun_fill_encap_opts_erspan(struct sk_buff *skb, 778 struct ip_tunnel_info *tun_info) 779 { 780 struct erspan_metadata *md; 781 struct nlattr *nest; 782 783 nest = nla_nest_start_noflag(skb, LWTUNNEL_IP_OPTS_ERSPAN); 784 if (!nest) 785 return -ENOMEM; 786 787 md = ip_tunnel_info_opts(tun_info); 788 if (nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_VER, md->version)) 789 goto err; 790 791 if (md->version == 1 && 792 nla_put_be32(skb, LWTUNNEL_IP_OPT_ERSPAN_INDEX, md->u.index)) 793 goto err; 794 795 if (md->version == 2 && 796 (nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_DIR, md->u.md2.dir) || 797 nla_put_u8(skb, LWTUNNEL_IP_OPT_ERSPAN_HWID, 798 get_hwid(&md->u.md2)))) 799 goto err; 800 801 nla_nest_end(skb, nest); 802 return 0; 803 err: 804 nla_nest_cancel(skb, nest); 805 return -ENOMEM; 806 } 807 808 static int ip_tun_fill_encap_opts(struct sk_buff *skb, int type, 809 struct ip_tunnel_info *tun_info) 810 { 811 struct nlattr *nest; 812 int err = 0; 813 814 if (!(tun_info->key.tun_flags & TUNNEL_OPTIONS_PRESENT)) 815 return 0; 816 817 nest = nla_nest_start_noflag(skb, type); 818 if (!nest) 819 return -ENOMEM; 820 821 if (tun_info->key.tun_flags & TUNNEL_GENEVE_OPT) 822 err = ip_tun_fill_encap_opts_geneve(skb, tun_info); 823 else if (tun_info->key.tun_flags & TUNNEL_VXLAN_OPT) 824 err = ip_tun_fill_encap_opts_vxlan(skb, tun_info); 825 else if (tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT) 826 err = ip_tun_fill_encap_opts_erspan(skb, tun_info); 827 828 if (err) { 829 nla_nest_cancel(skb, nest); 830 return err; 831 } 832 833 nla_nest_end(skb, nest); 834 return 0; 835 } 836 837 static int ip_tun_fill_encap_info(struct sk_buff *skb, 838 struct lwtunnel_state *lwtstate) 839 { 840 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 841 842 if (nla_put_be64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id, 843 LWTUNNEL_IP_PAD) || 844 nla_put_in_addr(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) || 845 nla_put_in_addr(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) || 846 nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) || 847 nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) || 848 nla_put_be16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags) || 849 ip_tun_fill_encap_opts(skb, LWTUNNEL_IP_OPTS, tun_info)) 850 return -ENOMEM; 851 852 return 0; 853 } 854 855 static int ip_tun_opts_nlsize(struct ip_tunnel_info *info) 856 { 857 int opt_len; 858 859 if (!(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT)) 860 return 0; 861 862 opt_len = nla_total_size(0); /* LWTUNNEL_IP_OPTS */ 863 if (info->key.tun_flags & TUNNEL_GENEVE_OPT) { 864 struct geneve_opt *opt; 865 int offset = 0; 866 867 opt_len += nla_total_size(0); /* LWTUNNEL_IP_OPTS_GENEVE */ 868 while (info->options_len > offset) { 869 opt = ip_tunnel_info_opts(info) + offset; 870 opt_len += nla_total_size(2) /* OPT_GENEVE_CLASS */ 871 + nla_total_size(1) /* OPT_GENEVE_TYPE */ 872 + nla_total_size(opt->length * 4); 873 /* OPT_GENEVE_DATA */ 874 offset += sizeof(*opt) + opt->length * 4; 875 } 876 } else if (info->key.tun_flags & TUNNEL_VXLAN_OPT) { 877 opt_len += nla_total_size(0) /* LWTUNNEL_IP_OPTS_VXLAN */ 878 + nla_total_size(4); /* OPT_VXLAN_GBP */ 879 } else if (info->key.tun_flags & TUNNEL_ERSPAN_OPT) { 880 struct erspan_metadata *md = ip_tunnel_info_opts(info); 881 882 opt_len += nla_total_size(0) /* LWTUNNEL_IP_OPTS_ERSPAN */ 883 + nla_total_size(1) /* OPT_ERSPAN_VER */ 884 + (md->version == 1 ? nla_total_size(4) 885 /* OPT_ERSPAN_INDEX (v1) */ 886 : nla_total_size(1) + 887 nla_total_size(1)); 888 /* OPT_ERSPAN_DIR + HWID (v2) */ 889 } 890 891 return opt_len; 892 } 893 894 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 895 { 896 return nla_total_size_64bit(8) /* LWTUNNEL_IP_ID */ 897 + nla_total_size(4) /* LWTUNNEL_IP_DST */ 898 + nla_total_size(4) /* LWTUNNEL_IP_SRC */ 899 + nla_total_size(1) /* LWTUNNEL_IP_TOS */ 900 + nla_total_size(1) /* LWTUNNEL_IP_TTL */ 901 + nla_total_size(2) /* LWTUNNEL_IP_FLAGS */ 902 + ip_tun_opts_nlsize(lwt_tun_info(lwtstate)); 903 /* LWTUNNEL_IP_OPTS */ 904 } 905 906 static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b) 907 { 908 struct ip_tunnel_info *info_a = lwt_tun_info(a); 909 struct ip_tunnel_info *info_b = lwt_tun_info(b); 910 911 return memcmp(info_a, info_b, sizeof(info_a->key)) || 912 info_a->mode != info_b->mode || 913 info_a->options_len != info_b->options_len || 914 memcmp(ip_tunnel_info_opts(info_a), 915 ip_tunnel_info_opts(info_b), info_a->options_len); 916 } 917 918 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = { 919 .build_state = ip_tun_build_state, 920 .destroy_state = ip_tun_destroy_state, 921 .fill_encap = ip_tun_fill_encap_info, 922 .get_encap_size = ip_tun_encap_nlsize, 923 .cmp_encap = ip_tun_cmp_encap, 924 .owner = THIS_MODULE, 925 }; 926 927 static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = { 928 [LWTUNNEL_IP6_UNSPEC] = { .strict_start_type = LWTUNNEL_IP6_OPTS }, 929 [LWTUNNEL_IP6_ID] = { .type = NLA_U64 }, 930 [LWTUNNEL_IP6_DST] = { .len = sizeof(struct in6_addr) }, 931 [LWTUNNEL_IP6_SRC] = { .len = sizeof(struct in6_addr) }, 932 [LWTUNNEL_IP6_HOPLIMIT] = { .type = NLA_U8 }, 933 [LWTUNNEL_IP6_TC] = { .type = NLA_U8 }, 934 [LWTUNNEL_IP6_FLAGS] = { .type = NLA_U16 }, 935 [LWTUNNEL_IP6_OPTS] = { .type = NLA_NESTED }, 936 }; 937 938 static int ip6_tun_build_state(struct net *net, struct nlattr *attr, 939 unsigned int family, const void *cfg, 940 struct lwtunnel_state **ts, 941 struct netlink_ext_ack *extack) 942 { 943 struct nlattr *tb[LWTUNNEL_IP6_MAX + 1]; 944 struct lwtunnel_state *new_state; 945 struct ip_tunnel_info *tun_info; 946 int err, opt_len; 947 948 err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP6_MAX, attr, 949 ip6_tun_policy, extack); 950 if (err < 0) 951 return err; 952 953 opt_len = ip_tun_get_optlen(tb[LWTUNNEL_IP6_OPTS], extack); 954 if (opt_len < 0) 955 return opt_len; 956 957 new_state = lwtunnel_state_alloc(sizeof(*tun_info) + opt_len); 958 if (!new_state) 959 return -ENOMEM; 960 961 new_state->type = LWTUNNEL_ENCAP_IP6; 962 963 tun_info = lwt_tun_info(new_state); 964 965 err = ip_tun_set_opts(tb[LWTUNNEL_IP6_OPTS], tun_info, extack); 966 if (err < 0) { 967 lwtstate_free(new_state); 968 return err; 969 } 970 971 if (tb[LWTUNNEL_IP6_ID]) 972 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP6_ID]); 973 974 if (tb[LWTUNNEL_IP6_DST]) 975 tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]); 976 977 if (tb[LWTUNNEL_IP6_SRC]) 978 tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]); 979 980 if (tb[LWTUNNEL_IP6_HOPLIMIT]) 981 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]); 982 983 if (tb[LWTUNNEL_IP6_TC]) 984 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]); 985 986 if (tb[LWTUNNEL_IP6_FLAGS]) 987 tun_info->key.tun_flags |= 988 (nla_get_be16(tb[LWTUNNEL_IP6_FLAGS]) & 989 ~TUNNEL_OPTIONS_PRESENT); 990 991 tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6; 992 tun_info->options_len = opt_len; 993 994 *ts = new_state; 995 996 return 0; 997 } 998 999 static int ip6_tun_fill_encap_info(struct sk_buff *skb, 1000 struct lwtunnel_state *lwtstate) 1001 { 1002 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 1003 1004 if (nla_put_be64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id, 1005 LWTUNNEL_IP6_PAD) || 1006 nla_put_in6_addr(skb, LWTUNNEL_IP6_DST, &tun_info->key.u.ipv6.dst) || 1007 nla_put_in6_addr(skb, LWTUNNEL_IP6_SRC, &tun_info->key.u.ipv6.src) || 1008 nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.tos) || 1009 nla_put_u8(skb, LWTUNNEL_IP6_HOPLIMIT, tun_info->key.ttl) || 1010 nla_put_be16(skb, LWTUNNEL_IP6_FLAGS, tun_info->key.tun_flags) || 1011 ip_tun_fill_encap_opts(skb, LWTUNNEL_IP6_OPTS, tun_info)) 1012 return -ENOMEM; 1013 1014 return 0; 1015 } 1016 1017 static int ip6_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 1018 { 1019 return nla_total_size_64bit(8) /* LWTUNNEL_IP6_ID */ 1020 + nla_total_size(16) /* LWTUNNEL_IP6_DST */ 1021 + nla_total_size(16) /* LWTUNNEL_IP6_SRC */ 1022 + nla_total_size(1) /* LWTUNNEL_IP6_HOPLIMIT */ 1023 + nla_total_size(1) /* LWTUNNEL_IP6_TC */ 1024 + nla_total_size(2) /* LWTUNNEL_IP6_FLAGS */ 1025 + ip_tun_opts_nlsize(lwt_tun_info(lwtstate)); 1026 /* LWTUNNEL_IP6_OPTS */ 1027 } 1028 1029 static const struct lwtunnel_encap_ops ip6_tun_lwt_ops = { 1030 .build_state = ip6_tun_build_state, 1031 .fill_encap = ip6_tun_fill_encap_info, 1032 .get_encap_size = ip6_tun_encap_nlsize, 1033 .cmp_encap = ip_tun_cmp_encap, 1034 .owner = THIS_MODULE, 1035 }; 1036 1037 void __init ip_tunnel_core_init(void) 1038 { 1039 /* If you land here, make sure whether increasing ip_tunnel_info's 1040 * options_len is a reasonable choice with its usage in front ends 1041 * (f.e., it's part of flow keys, etc). 1042 */ 1043 BUILD_BUG_ON(IP_TUNNEL_OPTS_MAX != 255); 1044 1045 lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP); 1046 lwtunnel_encap_add_ops(&ip6_tun_lwt_ops, LWTUNNEL_ENCAP_IP6); 1047 } 1048 1049 DEFINE_STATIC_KEY_FALSE(ip_tunnel_metadata_cnt); 1050 EXPORT_SYMBOL(ip_tunnel_metadata_cnt); 1051 1052 void ip_tunnel_need_metadata(void) 1053 { 1054 static_branch_inc(&ip_tunnel_metadata_cnt); 1055 } 1056 EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata); 1057 1058 void ip_tunnel_unneed_metadata(void) 1059 { 1060 static_branch_dec(&ip_tunnel_metadata_cnt); 1061 } 1062 EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata); 1063 1064 /* Returns either the correct skb->protocol value, or 0 if invalid. */ 1065 __be16 ip_tunnel_parse_protocol(const struct sk_buff *skb) 1066 { 1067 if (skb_network_header(skb) >= skb->head && 1068 (skb_network_header(skb) + sizeof(struct iphdr)) <= skb_tail_pointer(skb) && 1069 ip_hdr(skb)->version == 4) 1070 return htons(ETH_P_IP); 1071 if (skb_network_header(skb) >= skb->head && 1072 (skb_network_header(skb) + sizeof(struct ipv6hdr)) <= skb_tail_pointer(skb) && 1073 ipv6_hdr(skb)->version == 6) 1074 return htons(ETH_P_IPV6); 1075 return 0; 1076 } 1077 EXPORT_SYMBOL(ip_tunnel_parse_protocol); 1078 1079 const struct header_ops ip_tunnel_header_ops = { .parse_protocol = ip_tunnel_parse_protocol }; 1080 EXPORT_SYMBOL(ip_tunnel_header_ops); 1081