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/arp.h> 29 #include <net/checksum.h> 30 #include <net/dsfield.h> 31 #include <net/inet_ecn.h> 32 #include <net/xfrm.h> 33 #include <net/net_namespace.h> 34 #include <net/netns/generic.h> 35 #include <net/rtnetlink.h> 36 #include <net/dst_metadata.h> 37 38 const struct ip_tunnel_encap_ops __rcu * 39 iptun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; 40 EXPORT_SYMBOL(iptun_encaps); 41 42 const struct ip6_tnl_encap_ops __rcu * 43 ip6tun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; 44 EXPORT_SYMBOL(ip6tun_encaps); 45 46 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, 47 __be32 src, __be32 dst, __u8 proto, 48 __u8 tos, __u8 ttl, __be16 df, bool xnet) 49 { 50 int pkt_len = skb->len - skb_inner_network_offset(skb); 51 struct net *net = dev_net(rt->dst.dev); 52 struct net_device *dev = skb->dev; 53 struct iphdr *iph; 54 int err; 55 56 skb_scrub_packet(skb, xnet); 57 58 skb_clear_hash_if_not_l4(skb); 59 skb_dst_set(skb, &rt->dst); 60 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 61 62 /* Push down and install the IP header. */ 63 skb_push(skb, sizeof(struct iphdr)); 64 skb_reset_network_header(skb); 65 66 iph = ip_hdr(skb); 67 68 iph->version = 4; 69 iph->ihl = sizeof(struct iphdr) >> 2; 70 iph->frag_off = ip_mtu_locked(&rt->dst) ? 0 : df; 71 iph->protocol = proto; 72 iph->tos = tos; 73 iph->daddr = dst; 74 iph->saddr = src; 75 iph->ttl = ttl; 76 __ip_select_ident(net, iph, skb_shinfo(skb)->gso_segs ?: 1); 77 78 err = ip_local_out(net, sk, skb); 79 80 if (dev) { 81 if (unlikely(net_xmit_eval(err))) 82 pkt_len = 0; 83 iptunnel_xmit_stats(dev, pkt_len); 84 } 85 } 86 EXPORT_SYMBOL_GPL(iptunnel_xmit); 87 88 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len, 89 __be16 inner_proto, bool raw_proto, bool xnet) 90 { 91 if (unlikely(!pskb_may_pull(skb, hdr_len))) 92 return -ENOMEM; 93 94 skb_pull_rcsum(skb, hdr_len); 95 96 if (!raw_proto && inner_proto == htons(ETH_P_TEB)) { 97 struct ethhdr *eh; 98 99 if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) 100 return -ENOMEM; 101 102 eh = (struct ethhdr *)skb->data; 103 if (likely(eth_proto_is_802_3(eh->h_proto))) 104 skb->protocol = eh->h_proto; 105 else 106 skb->protocol = htons(ETH_P_802_2); 107 108 } else { 109 skb->protocol = inner_proto; 110 } 111 112 skb_clear_hash_if_not_l4(skb); 113 __vlan_hwaccel_clear_tag(skb); 114 skb_set_queue_mapping(skb, 0); 115 skb_scrub_packet(skb, xnet); 116 117 return iptunnel_pull_offloads(skb); 118 } 119 EXPORT_SYMBOL_GPL(__iptunnel_pull_header); 120 121 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md, 122 gfp_t flags) 123 { 124 struct metadata_dst *res; 125 struct ip_tunnel_info *dst, *src; 126 127 if (!md || md->type != METADATA_IP_TUNNEL || 128 md->u.tun_info.mode & IP_TUNNEL_INFO_TX) 129 return NULL; 130 131 src = &md->u.tun_info; 132 res = metadata_dst_alloc(src->options_len, METADATA_IP_TUNNEL, flags); 133 if (!res) 134 return NULL; 135 136 dst = &res->u.tun_info; 137 dst->key.tun_id = src->key.tun_id; 138 if (src->mode & IP_TUNNEL_INFO_IPV6) 139 memcpy(&dst->key.u.ipv6.dst, &src->key.u.ipv6.src, 140 sizeof(struct in6_addr)); 141 else 142 dst->key.u.ipv4.dst = src->key.u.ipv4.src; 143 dst->key.tun_flags = src->key.tun_flags; 144 dst->mode = src->mode | IP_TUNNEL_INFO_TX; 145 ip_tunnel_info_opts_set(dst, ip_tunnel_info_opts(src), 146 src->options_len, 0); 147 148 return res; 149 } 150 EXPORT_SYMBOL_GPL(iptunnel_metadata_reply); 151 152 int iptunnel_handle_offloads(struct sk_buff *skb, 153 int gso_type_mask) 154 { 155 int err; 156 157 if (likely(!skb->encapsulation)) { 158 skb_reset_inner_headers(skb); 159 skb->encapsulation = 1; 160 } 161 162 if (skb_is_gso(skb)) { 163 err = skb_header_unclone(skb, GFP_ATOMIC); 164 if (unlikely(err)) 165 return err; 166 skb_shinfo(skb)->gso_type |= gso_type_mask; 167 return 0; 168 } 169 170 if (skb->ip_summed != CHECKSUM_PARTIAL) { 171 skb->ip_summed = CHECKSUM_NONE; 172 /* We clear encapsulation here to prevent badly-written 173 * drivers potentially deciding to offload an inner checksum 174 * if we set CHECKSUM_PARTIAL on the outer header. 175 * This should go away when the drivers are all fixed. 176 */ 177 skb->encapsulation = 0; 178 } 179 180 return 0; 181 } 182 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); 183 184 /* Often modified stats are per cpu, other are shared (netdev->stats) */ 185 void ip_tunnel_get_stats64(struct net_device *dev, 186 struct rtnl_link_stats64 *tot) 187 { 188 int i; 189 190 netdev_stats_to_stats64(tot, &dev->stats); 191 192 for_each_possible_cpu(i) { 193 const struct pcpu_sw_netstats *tstats = 194 per_cpu_ptr(dev->tstats, i); 195 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 196 unsigned int start; 197 198 do { 199 start = u64_stats_fetch_begin_irq(&tstats->syncp); 200 rx_packets = tstats->rx_packets; 201 tx_packets = tstats->tx_packets; 202 rx_bytes = tstats->rx_bytes; 203 tx_bytes = tstats->tx_bytes; 204 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); 205 206 tot->rx_packets += rx_packets; 207 tot->tx_packets += tx_packets; 208 tot->rx_bytes += rx_bytes; 209 tot->tx_bytes += tx_bytes; 210 } 211 } 212 EXPORT_SYMBOL_GPL(ip_tunnel_get_stats64); 213 214 static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = { 215 [LWTUNNEL_IP_ID] = { .type = NLA_U64 }, 216 [LWTUNNEL_IP_DST] = { .type = NLA_U32 }, 217 [LWTUNNEL_IP_SRC] = { .type = NLA_U32 }, 218 [LWTUNNEL_IP_TTL] = { .type = NLA_U8 }, 219 [LWTUNNEL_IP_TOS] = { .type = NLA_U8 }, 220 [LWTUNNEL_IP_FLAGS] = { .type = NLA_U16 }, 221 }; 222 223 static int ip_tun_build_state(struct nlattr *attr, 224 unsigned int family, const void *cfg, 225 struct lwtunnel_state **ts, 226 struct netlink_ext_ack *extack) 227 { 228 struct ip_tunnel_info *tun_info; 229 struct lwtunnel_state *new_state; 230 struct nlattr *tb[LWTUNNEL_IP_MAX + 1]; 231 int err; 232 233 err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_MAX, attr, 234 ip_tun_policy, extack); 235 if (err < 0) 236 return err; 237 238 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 239 if (!new_state) 240 return -ENOMEM; 241 242 new_state->type = LWTUNNEL_ENCAP_IP; 243 244 tun_info = lwt_tun_info(new_state); 245 246 #ifdef CONFIG_DST_CACHE 247 err = dst_cache_init(&tun_info->dst_cache, GFP_KERNEL); 248 if (err) { 249 lwtstate_free(new_state); 250 return err; 251 } 252 #endif 253 254 if (tb[LWTUNNEL_IP_ID]) 255 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP_ID]); 256 257 if (tb[LWTUNNEL_IP_DST]) 258 tun_info->key.u.ipv4.dst = nla_get_in_addr(tb[LWTUNNEL_IP_DST]); 259 260 if (tb[LWTUNNEL_IP_SRC]) 261 tun_info->key.u.ipv4.src = nla_get_in_addr(tb[LWTUNNEL_IP_SRC]); 262 263 if (tb[LWTUNNEL_IP_TTL]) 264 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]); 265 266 if (tb[LWTUNNEL_IP_TOS]) 267 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]); 268 269 if (tb[LWTUNNEL_IP_FLAGS]) 270 tun_info->key.tun_flags = nla_get_be16(tb[LWTUNNEL_IP_FLAGS]); 271 272 tun_info->mode = IP_TUNNEL_INFO_TX; 273 tun_info->options_len = 0; 274 275 *ts = new_state; 276 277 return 0; 278 } 279 280 static void ip_tun_destroy_state(struct lwtunnel_state *lwtstate) 281 { 282 #ifdef CONFIG_DST_CACHE 283 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 284 285 dst_cache_destroy(&tun_info->dst_cache); 286 #endif 287 } 288 289 static int ip_tun_fill_encap_info(struct sk_buff *skb, 290 struct lwtunnel_state *lwtstate) 291 { 292 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 293 294 if (nla_put_be64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id, 295 LWTUNNEL_IP_PAD) || 296 nla_put_in_addr(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) || 297 nla_put_in_addr(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) || 298 nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) || 299 nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) || 300 nla_put_be16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags)) 301 return -ENOMEM; 302 303 return 0; 304 } 305 306 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 307 { 308 return nla_total_size_64bit(8) /* LWTUNNEL_IP_ID */ 309 + nla_total_size(4) /* LWTUNNEL_IP_DST */ 310 + nla_total_size(4) /* LWTUNNEL_IP_SRC */ 311 + nla_total_size(1) /* LWTUNNEL_IP_TOS */ 312 + nla_total_size(1) /* LWTUNNEL_IP_TTL */ 313 + nla_total_size(2); /* LWTUNNEL_IP_FLAGS */ 314 } 315 316 static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b) 317 { 318 return memcmp(lwt_tun_info(a), lwt_tun_info(b), 319 sizeof(struct ip_tunnel_info)); 320 } 321 322 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = { 323 .build_state = ip_tun_build_state, 324 .destroy_state = ip_tun_destroy_state, 325 .fill_encap = ip_tun_fill_encap_info, 326 .get_encap_size = ip_tun_encap_nlsize, 327 .cmp_encap = ip_tun_cmp_encap, 328 .owner = THIS_MODULE, 329 }; 330 331 static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = { 332 [LWTUNNEL_IP6_ID] = { .type = NLA_U64 }, 333 [LWTUNNEL_IP6_DST] = { .len = sizeof(struct in6_addr) }, 334 [LWTUNNEL_IP6_SRC] = { .len = sizeof(struct in6_addr) }, 335 [LWTUNNEL_IP6_HOPLIMIT] = { .type = NLA_U8 }, 336 [LWTUNNEL_IP6_TC] = { .type = NLA_U8 }, 337 [LWTUNNEL_IP6_FLAGS] = { .type = NLA_U16 }, 338 }; 339 340 static int ip6_tun_build_state(struct nlattr *attr, 341 unsigned int family, const void *cfg, 342 struct lwtunnel_state **ts, 343 struct netlink_ext_ack *extack) 344 { 345 struct ip_tunnel_info *tun_info; 346 struct lwtunnel_state *new_state; 347 struct nlattr *tb[LWTUNNEL_IP6_MAX + 1]; 348 int err; 349 350 err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP6_MAX, attr, 351 ip6_tun_policy, extack); 352 if (err < 0) 353 return err; 354 355 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 356 if (!new_state) 357 return -ENOMEM; 358 359 new_state->type = LWTUNNEL_ENCAP_IP6; 360 361 tun_info = lwt_tun_info(new_state); 362 363 if (tb[LWTUNNEL_IP6_ID]) 364 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP6_ID]); 365 366 if (tb[LWTUNNEL_IP6_DST]) 367 tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]); 368 369 if (tb[LWTUNNEL_IP6_SRC]) 370 tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]); 371 372 if (tb[LWTUNNEL_IP6_HOPLIMIT]) 373 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]); 374 375 if (tb[LWTUNNEL_IP6_TC]) 376 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]); 377 378 if (tb[LWTUNNEL_IP6_FLAGS]) 379 tun_info->key.tun_flags = nla_get_be16(tb[LWTUNNEL_IP6_FLAGS]); 380 381 tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6; 382 tun_info->options_len = 0; 383 384 *ts = new_state; 385 386 return 0; 387 } 388 389 static int ip6_tun_fill_encap_info(struct sk_buff *skb, 390 struct lwtunnel_state *lwtstate) 391 { 392 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 393 394 if (nla_put_be64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id, 395 LWTUNNEL_IP6_PAD) || 396 nla_put_in6_addr(skb, LWTUNNEL_IP6_DST, &tun_info->key.u.ipv6.dst) || 397 nla_put_in6_addr(skb, LWTUNNEL_IP6_SRC, &tun_info->key.u.ipv6.src) || 398 nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.tos) || 399 nla_put_u8(skb, LWTUNNEL_IP6_HOPLIMIT, tun_info->key.ttl) || 400 nla_put_be16(skb, LWTUNNEL_IP6_FLAGS, tun_info->key.tun_flags)) 401 return -ENOMEM; 402 403 return 0; 404 } 405 406 static int ip6_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 407 { 408 return nla_total_size_64bit(8) /* LWTUNNEL_IP6_ID */ 409 + nla_total_size(16) /* LWTUNNEL_IP6_DST */ 410 + nla_total_size(16) /* LWTUNNEL_IP6_SRC */ 411 + nla_total_size(1) /* LWTUNNEL_IP6_HOPLIMIT */ 412 + nla_total_size(1) /* LWTUNNEL_IP6_TC */ 413 + nla_total_size(2); /* LWTUNNEL_IP6_FLAGS */ 414 } 415 416 static const struct lwtunnel_encap_ops ip6_tun_lwt_ops = { 417 .build_state = ip6_tun_build_state, 418 .fill_encap = ip6_tun_fill_encap_info, 419 .get_encap_size = ip6_tun_encap_nlsize, 420 .cmp_encap = ip_tun_cmp_encap, 421 .owner = THIS_MODULE, 422 }; 423 424 void __init ip_tunnel_core_init(void) 425 { 426 /* If you land here, make sure whether increasing ip_tunnel_info's 427 * options_len is a reasonable choice with its usage in front ends 428 * (f.e., it's part of flow keys, etc). 429 */ 430 BUILD_BUG_ON(IP_TUNNEL_OPTS_MAX != 255); 431 432 lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP); 433 lwtunnel_encap_add_ops(&ip6_tun_lwt_ops, LWTUNNEL_ENCAP_IP6); 434 } 435 436 DEFINE_STATIC_KEY_FALSE(ip_tunnel_metadata_cnt); 437 EXPORT_SYMBOL(ip_tunnel_metadata_cnt); 438 439 void ip_tunnel_need_metadata(void) 440 { 441 static_branch_inc(&ip_tunnel_metadata_cnt); 442 } 443 EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata); 444 445 void ip_tunnel_unneed_metadata(void) 446 { 447 static_branch_dec(&ip_tunnel_metadata_cnt); 448 } 449 EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata); 450