1 /* 2 * Copyright (c) 2013 Nicira, Inc. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of version 2 of the GNU General Public 6 * License as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program; if not, write to the Free Software 15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 16 * 02110-1301, USA 17 */ 18 19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 20 21 #include <linux/types.h> 22 #include <linux/kernel.h> 23 #include <linux/skbuff.h> 24 #include <linux/netdevice.h> 25 #include <linux/in.h> 26 #include <linux/if_arp.h> 27 #include <linux/init.h> 28 #include <linux/in6.h> 29 #include <linux/inetdevice.h> 30 #include <linux/netfilter_ipv4.h> 31 #include <linux/etherdevice.h> 32 #include <linux/if_ether.h> 33 #include <linux/if_vlan.h> 34 #include <linux/static_key.h> 35 36 #include <net/ip.h> 37 #include <net/icmp.h> 38 #include <net/protocol.h> 39 #include <net/ip_tunnels.h> 40 #include <net/ip6_tunnel.h> 41 #include <net/arp.h> 42 #include <net/checksum.h> 43 #include <net/dsfield.h> 44 #include <net/inet_ecn.h> 45 #include <net/xfrm.h> 46 #include <net/net_namespace.h> 47 #include <net/netns/generic.h> 48 #include <net/rtnetlink.h> 49 #include <net/dst_metadata.h> 50 51 const struct ip_tunnel_encap_ops __rcu * 52 iptun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; 53 EXPORT_SYMBOL(iptun_encaps); 54 55 const struct ip6_tnl_encap_ops __rcu * 56 ip6tun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; 57 EXPORT_SYMBOL(ip6tun_encaps); 58 59 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, 60 __be32 src, __be32 dst, __u8 proto, 61 __u8 tos, __u8 ttl, __be16 df, bool xnet) 62 { 63 int pkt_len = skb->len - skb_inner_network_offset(skb); 64 struct net *net = dev_net(rt->dst.dev); 65 struct net_device *dev = skb->dev; 66 struct iphdr *iph; 67 int err; 68 69 skb_scrub_packet(skb, xnet); 70 71 skb_clear_hash_if_not_l4(skb); 72 skb_dst_set(skb, &rt->dst); 73 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 74 75 /* Push down and install the IP header. */ 76 skb_push(skb, sizeof(struct iphdr)); 77 skb_reset_network_header(skb); 78 79 iph = ip_hdr(skb); 80 81 iph->version = 4; 82 iph->ihl = sizeof(struct iphdr) >> 2; 83 iph->frag_off = ip_mtu_locked(&rt->dst) ? 0 : df; 84 iph->protocol = proto; 85 iph->tos = tos; 86 iph->daddr = dst; 87 iph->saddr = src; 88 iph->ttl = ttl; 89 __ip_select_ident(net, iph, skb_shinfo(skb)->gso_segs ?: 1); 90 91 err = ip_local_out(net, sk, skb); 92 if (unlikely(net_xmit_eval(err))) 93 pkt_len = 0; 94 iptunnel_xmit_stats(dev, pkt_len); 95 } 96 EXPORT_SYMBOL_GPL(iptunnel_xmit); 97 98 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len, 99 __be16 inner_proto, bool raw_proto, bool xnet) 100 { 101 if (unlikely(!pskb_may_pull(skb, hdr_len))) 102 return -ENOMEM; 103 104 skb_pull_rcsum(skb, hdr_len); 105 106 if (!raw_proto && inner_proto == htons(ETH_P_TEB)) { 107 struct ethhdr *eh; 108 109 if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) 110 return -ENOMEM; 111 112 eh = (struct ethhdr *)skb->data; 113 if (likely(eth_proto_is_802_3(eh->h_proto))) 114 skb->protocol = eh->h_proto; 115 else 116 skb->protocol = htons(ETH_P_802_2); 117 118 } else { 119 skb->protocol = inner_proto; 120 } 121 122 skb_clear_hash_if_not_l4(skb); 123 __vlan_hwaccel_clear_tag(skb); 124 skb_set_queue_mapping(skb, 0); 125 skb_scrub_packet(skb, xnet); 126 127 return iptunnel_pull_offloads(skb); 128 } 129 EXPORT_SYMBOL_GPL(__iptunnel_pull_header); 130 131 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md, 132 gfp_t flags) 133 { 134 struct metadata_dst *res; 135 struct ip_tunnel_info *dst, *src; 136 137 if (!md || md->type != METADATA_IP_TUNNEL || 138 md->u.tun_info.mode & IP_TUNNEL_INFO_TX) 139 140 return NULL; 141 142 res = metadata_dst_alloc(0, METADATA_IP_TUNNEL, flags); 143 if (!res) 144 return NULL; 145 146 dst = &res->u.tun_info; 147 src = &md->u.tun_info; 148 dst->key.tun_id = src->key.tun_id; 149 if (src->mode & IP_TUNNEL_INFO_IPV6) 150 memcpy(&dst->key.u.ipv6.dst, &src->key.u.ipv6.src, 151 sizeof(struct in6_addr)); 152 else 153 dst->key.u.ipv4.dst = src->key.u.ipv4.src; 154 dst->key.tun_flags = src->key.tun_flags; 155 dst->mode = src->mode | IP_TUNNEL_INFO_TX; 156 157 return res; 158 } 159 EXPORT_SYMBOL_GPL(iptunnel_metadata_reply); 160 161 int iptunnel_handle_offloads(struct sk_buff *skb, 162 int gso_type_mask) 163 { 164 int err; 165 166 if (likely(!skb->encapsulation)) { 167 skb_reset_inner_headers(skb); 168 skb->encapsulation = 1; 169 } 170 171 if (skb_is_gso(skb)) { 172 err = skb_header_unclone(skb, GFP_ATOMIC); 173 if (unlikely(err)) 174 return err; 175 skb_shinfo(skb)->gso_type |= gso_type_mask; 176 return 0; 177 } 178 179 if (skb->ip_summed != CHECKSUM_PARTIAL) { 180 skb->ip_summed = CHECKSUM_NONE; 181 /* We clear encapsulation here to prevent badly-written 182 * drivers potentially deciding to offload an inner checksum 183 * if we set CHECKSUM_PARTIAL on the outer header. 184 * This should go away when the drivers are all fixed. 185 */ 186 skb->encapsulation = 0; 187 } 188 189 return 0; 190 } 191 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); 192 193 /* Often modified stats are per cpu, other are shared (netdev->stats) */ 194 void ip_tunnel_get_stats64(struct net_device *dev, 195 struct rtnl_link_stats64 *tot) 196 { 197 int i; 198 199 netdev_stats_to_stats64(tot, &dev->stats); 200 201 for_each_possible_cpu(i) { 202 const struct pcpu_sw_netstats *tstats = 203 per_cpu_ptr(dev->tstats, i); 204 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 205 unsigned int start; 206 207 do { 208 start = u64_stats_fetch_begin_irq(&tstats->syncp); 209 rx_packets = tstats->rx_packets; 210 tx_packets = tstats->tx_packets; 211 rx_bytes = tstats->rx_bytes; 212 tx_bytes = tstats->tx_bytes; 213 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); 214 215 tot->rx_packets += rx_packets; 216 tot->tx_packets += tx_packets; 217 tot->rx_bytes += rx_bytes; 218 tot->tx_bytes += tx_bytes; 219 } 220 } 221 EXPORT_SYMBOL_GPL(ip_tunnel_get_stats64); 222 223 static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = { 224 [LWTUNNEL_IP_ID] = { .type = NLA_U64 }, 225 [LWTUNNEL_IP_DST] = { .type = NLA_U32 }, 226 [LWTUNNEL_IP_SRC] = { .type = NLA_U32 }, 227 [LWTUNNEL_IP_TTL] = { .type = NLA_U8 }, 228 [LWTUNNEL_IP_TOS] = { .type = NLA_U8 }, 229 [LWTUNNEL_IP_FLAGS] = { .type = NLA_U16 }, 230 }; 231 232 static int ip_tun_build_state(struct nlattr *attr, 233 unsigned int family, const void *cfg, 234 struct lwtunnel_state **ts, 235 struct netlink_ext_ack *extack) 236 { 237 struct ip_tunnel_info *tun_info; 238 struct lwtunnel_state *new_state; 239 struct nlattr *tb[LWTUNNEL_IP_MAX + 1]; 240 int err; 241 242 err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP_MAX, attr, 243 ip_tun_policy, extack); 244 if (err < 0) 245 return err; 246 247 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 248 if (!new_state) 249 return -ENOMEM; 250 251 new_state->type = LWTUNNEL_ENCAP_IP; 252 253 tun_info = lwt_tun_info(new_state); 254 255 #ifdef CONFIG_DST_CACHE 256 err = dst_cache_init(&tun_info->dst_cache, GFP_KERNEL); 257 if (err) { 258 lwtstate_free(new_state); 259 return err; 260 } 261 #endif 262 263 if (tb[LWTUNNEL_IP_ID]) 264 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP_ID]); 265 266 if (tb[LWTUNNEL_IP_DST]) 267 tun_info->key.u.ipv4.dst = nla_get_in_addr(tb[LWTUNNEL_IP_DST]); 268 269 if (tb[LWTUNNEL_IP_SRC]) 270 tun_info->key.u.ipv4.src = nla_get_in_addr(tb[LWTUNNEL_IP_SRC]); 271 272 if (tb[LWTUNNEL_IP_TTL]) 273 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]); 274 275 if (tb[LWTUNNEL_IP_TOS]) 276 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]); 277 278 if (tb[LWTUNNEL_IP_FLAGS]) 279 tun_info->key.tun_flags = nla_get_be16(tb[LWTUNNEL_IP_FLAGS]); 280 281 tun_info->mode = IP_TUNNEL_INFO_TX; 282 tun_info->options_len = 0; 283 284 *ts = new_state; 285 286 return 0; 287 } 288 289 static void ip_tun_destroy_state(struct lwtunnel_state *lwtstate) 290 { 291 #ifdef CONFIG_DST_CACHE 292 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 293 294 dst_cache_destroy(&tun_info->dst_cache); 295 #endif 296 } 297 298 static int ip_tun_fill_encap_info(struct sk_buff *skb, 299 struct lwtunnel_state *lwtstate) 300 { 301 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 302 303 if (nla_put_be64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id, 304 LWTUNNEL_IP_PAD) || 305 nla_put_in_addr(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) || 306 nla_put_in_addr(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) || 307 nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) || 308 nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) || 309 nla_put_be16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags)) 310 return -ENOMEM; 311 312 return 0; 313 } 314 315 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 316 { 317 return nla_total_size_64bit(8) /* LWTUNNEL_IP_ID */ 318 + nla_total_size(4) /* LWTUNNEL_IP_DST */ 319 + nla_total_size(4) /* LWTUNNEL_IP_SRC */ 320 + nla_total_size(1) /* LWTUNNEL_IP_TOS */ 321 + nla_total_size(1) /* LWTUNNEL_IP_TTL */ 322 + nla_total_size(2); /* LWTUNNEL_IP_FLAGS */ 323 } 324 325 static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b) 326 { 327 return memcmp(lwt_tun_info(a), lwt_tun_info(b), 328 sizeof(struct ip_tunnel_info)); 329 } 330 331 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = { 332 .build_state = ip_tun_build_state, 333 .destroy_state = ip_tun_destroy_state, 334 .fill_encap = ip_tun_fill_encap_info, 335 .get_encap_size = ip_tun_encap_nlsize, 336 .cmp_encap = ip_tun_cmp_encap, 337 .owner = THIS_MODULE, 338 }; 339 340 static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = { 341 [LWTUNNEL_IP6_ID] = { .type = NLA_U64 }, 342 [LWTUNNEL_IP6_DST] = { .len = sizeof(struct in6_addr) }, 343 [LWTUNNEL_IP6_SRC] = { .len = sizeof(struct in6_addr) }, 344 [LWTUNNEL_IP6_HOPLIMIT] = { .type = NLA_U8 }, 345 [LWTUNNEL_IP6_TC] = { .type = NLA_U8 }, 346 [LWTUNNEL_IP6_FLAGS] = { .type = NLA_U16 }, 347 }; 348 349 static int ip6_tun_build_state(struct nlattr *attr, 350 unsigned int family, const void *cfg, 351 struct lwtunnel_state **ts, 352 struct netlink_ext_ack *extack) 353 { 354 struct ip_tunnel_info *tun_info; 355 struct lwtunnel_state *new_state; 356 struct nlattr *tb[LWTUNNEL_IP6_MAX + 1]; 357 int err; 358 359 err = nla_parse_nested_deprecated(tb, LWTUNNEL_IP6_MAX, attr, 360 ip6_tun_policy, extack); 361 if (err < 0) 362 return err; 363 364 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 365 if (!new_state) 366 return -ENOMEM; 367 368 new_state->type = LWTUNNEL_ENCAP_IP6; 369 370 tun_info = lwt_tun_info(new_state); 371 372 if (tb[LWTUNNEL_IP6_ID]) 373 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP6_ID]); 374 375 if (tb[LWTUNNEL_IP6_DST]) 376 tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]); 377 378 if (tb[LWTUNNEL_IP6_SRC]) 379 tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]); 380 381 if (tb[LWTUNNEL_IP6_HOPLIMIT]) 382 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]); 383 384 if (tb[LWTUNNEL_IP6_TC]) 385 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]); 386 387 if (tb[LWTUNNEL_IP6_FLAGS]) 388 tun_info->key.tun_flags = nla_get_be16(tb[LWTUNNEL_IP6_FLAGS]); 389 390 tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6; 391 tun_info->options_len = 0; 392 393 *ts = new_state; 394 395 return 0; 396 } 397 398 static int ip6_tun_fill_encap_info(struct sk_buff *skb, 399 struct lwtunnel_state *lwtstate) 400 { 401 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 402 403 if (nla_put_be64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id, 404 LWTUNNEL_IP6_PAD) || 405 nla_put_in6_addr(skb, LWTUNNEL_IP6_DST, &tun_info->key.u.ipv6.dst) || 406 nla_put_in6_addr(skb, LWTUNNEL_IP6_SRC, &tun_info->key.u.ipv6.src) || 407 nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.tos) || 408 nla_put_u8(skb, LWTUNNEL_IP6_HOPLIMIT, tun_info->key.ttl) || 409 nla_put_be16(skb, LWTUNNEL_IP6_FLAGS, tun_info->key.tun_flags)) 410 return -ENOMEM; 411 412 return 0; 413 } 414 415 static int ip6_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 416 { 417 return nla_total_size_64bit(8) /* LWTUNNEL_IP6_ID */ 418 + nla_total_size(16) /* LWTUNNEL_IP6_DST */ 419 + nla_total_size(16) /* LWTUNNEL_IP6_SRC */ 420 + nla_total_size(1) /* LWTUNNEL_IP6_HOPLIMIT */ 421 + nla_total_size(1) /* LWTUNNEL_IP6_TC */ 422 + nla_total_size(2); /* LWTUNNEL_IP6_FLAGS */ 423 } 424 425 static const struct lwtunnel_encap_ops ip6_tun_lwt_ops = { 426 .build_state = ip6_tun_build_state, 427 .fill_encap = ip6_tun_fill_encap_info, 428 .get_encap_size = ip6_tun_encap_nlsize, 429 .cmp_encap = ip_tun_cmp_encap, 430 .owner = THIS_MODULE, 431 }; 432 433 void __init ip_tunnel_core_init(void) 434 { 435 /* If you land here, make sure whether increasing ip_tunnel_info's 436 * options_len is a reasonable choice with its usage in front ends 437 * (f.e., it's part of flow keys, etc). 438 */ 439 BUILD_BUG_ON(IP_TUNNEL_OPTS_MAX != 255); 440 441 lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP); 442 lwtunnel_encap_add_ops(&ip6_tun_lwt_ops, LWTUNNEL_ENCAP_IP6); 443 } 444 445 DEFINE_STATIC_KEY_FALSE(ip_tunnel_metadata_cnt); 446 EXPORT_SYMBOL(ip_tunnel_metadata_cnt); 447 448 void ip_tunnel_need_metadata(void) 449 { 450 static_branch_inc(&ip_tunnel_metadata_cnt); 451 } 452 EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata); 453 454 void ip_tunnel_unneed_metadata(void) 455 { 456 static_branch_dec(&ip_tunnel_metadata_cnt); 457 } 458 EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata); 459