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