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 = 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 skb->vlan_tci = 0; 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->u.tun_info.mode & IP_TUNNEL_INFO_TX) 138 return NULL; 139 140 res = metadata_dst_alloc(0, flags); 141 if (!res) 142 return NULL; 143 144 dst = &res->u.tun_info; 145 src = &md->u.tun_info; 146 dst->key.tun_id = src->key.tun_id; 147 if (src->mode & IP_TUNNEL_INFO_IPV6) 148 memcpy(&dst->key.u.ipv6.dst, &src->key.u.ipv6.src, 149 sizeof(struct in6_addr)); 150 else 151 dst->key.u.ipv4.dst = src->key.u.ipv4.src; 152 dst->mode = src->mode | IP_TUNNEL_INFO_TX; 153 154 return res; 155 } 156 EXPORT_SYMBOL_GPL(iptunnel_metadata_reply); 157 158 int iptunnel_handle_offloads(struct sk_buff *skb, 159 int gso_type_mask) 160 { 161 int err; 162 163 if (likely(!skb->encapsulation)) { 164 skb_reset_inner_headers(skb); 165 skb->encapsulation = 1; 166 } 167 168 if (skb_is_gso(skb)) { 169 err = skb_header_unclone(skb, GFP_ATOMIC); 170 if (unlikely(err)) 171 return err; 172 skb_shinfo(skb)->gso_type |= gso_type_mask; 173 return 0; 174 } 175 176 if (skb->ip_summed != CHECKSUM_PARTIAL) { 177 skb->ip_summed = CHECKSUM_NONE; 178 /* We clear encapsulation here to prevent badly-written 179 * drivers potentially deciding to offload an inner checksum 180 * if we set CHECKSUM_PARTIAL on the outer header. 181 * This should go away when the drivers are all fixed. 182 */ 183 skb->encapsulation = 0; 184 } 185 186 return 0; 187 } 188 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); 189 190 /* Often modified stats are per cpu, other are shared (netdev->stats) */ 191 void ip_tunnel_get_stats64(struct net_device *dev, 192 struct rtnl_link_stats64 *tot) 193 { 194 int i; 195 196 netdev_stats_to_stats64(tot, &dev->stats); 197 198 for_each_possible_cpu(i) { 199 const struct pcpu_sw_netstats *tstats = 200 per_cpu_ptr(dev->tstats, i); 201 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 202 unsigned int start; 203 204 do { 205 start = u64_stats_fetch_begin_irq(&tstats->syncp); 206 rx_packets = tstats->rx_packets; 207 tx_packets = tstats->tx_packets; 208 rx_bytes = tstats->rx_bytes; 209 tx_bytes = tstats->tx_bytes; 210 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); 211 212 tot->rx_packets += rx_packets; 213 tot->tx_packets += tx_packets; 214 tot->rx_bytes += rx_bytes; 215 tot->tx_bytes += tx_bytes; 216 } 217 } 218 EXPORT_SYMBOL_GPL(ip_tunnel_get_stats64); 219 220 static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = { 221 [LWTUNNEL_IP_ID] = { .type = NLA_U64 }, 222 [LWTUNNEL_IP_DST] = { .type = NLA_U32 }, 223 [LWTUNNEL_IP_SRC] = { .type = NLA_U32 }, 224 [LWTUNNEL_IP_TTL] = { .type = NLA_U8 }, 225 [LWTUNNEL_IP_TOS] = { .type = NLA_U8 }, 226 [LWTUNNEL_IP_FLAGS] = { .type = NLA_U16 }, 227 }; 228 229 static int ip_tun_build_state(struct net_device *dev, struct nlattr *attr, 230 unsigned int family, const void *cfg, 231 struct lwtunnel_state **ts) 232 { 233 struct ip_tunnel_info *tun_info; 234 struct lwtunnel_state *new_state; 235 struct nlattr *tb[LWTUNNEL_IP_MAX + 1]; 236 int err; 237 238 err = nla_parse_nested(tb, LWTUNNEL_IP_MAX, attr, ip_tun_policy); 239 if (err < 0) 240 return err; 241 242 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 243 if (!new_state) 244 return -ENOMEM; 245 246 new_state->type = LWTUNNEL_ENCAP_IP; 247 248 tun_info = lwt_tun_info(new_state); 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 int ip_tun_fill_encap_info(struct sk_buff *skb, 277 struct lwtunnel_state *lwtstate) 278 { 279 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 280 281 if (nla_put_be64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id, 282 LWTUNNEL_IP_PAD) || 283 nla_put_in_addr(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) || 284 nla_put_in_addr(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) || 285 nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) || 286 nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) || 287 nla_put_be16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags)) 288 return -ENOMEM; 289 290 return 0; 291 } 292 293 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 294 { 295 return nla_total_size_64bit(8) /* LWTUNNEL_IP_ID */ 296 + nla_total_size(4) /* LWTUNNEL_IP_DST */ 297 + nla_total_size(4) /* LWTUNNEL_IP_SRC */ 298 + nla_total_size(1) /* LWTUNNEL_IP_TOS */ 299 + nla_total_size(1) /* LWTUNNEL_IP_TTL */ 300 + nla_total_size(2); /* LWTUNNEL_IP_FLAGS */ 301 } 302 303 static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b) 304 { 305 return memcmp(lwt_tun_info(a), lwt_tun_info(b), 306 sizeof(struct ip_tunnel_info)); 307 } 308 309 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = { 310 .build_state = ip_tun_build_state, 311 .fill_encap = ip_tun_fill_encap_info, 312 .get_encap_size = ip_tun_encap_nlsize, 313 .cmp_encap = ip_tun_cmp_encap, 314 }; 315 316 static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = { 317 [LWTUNNEL_IP6_ID] = { .type = NLA_U64 }, 318 [LWTUNNEL_IP6_DST] = { .len = sizeof(struct in6_addr) }, 319 [LWTUNNEL_IP6_SRC] = { .len = sizeof(struct in6_addr) }, 320 [LWTUNNEL_IP6_HOPLIMIT] = { .type = NLA_U8 }, 321 [LWTUNNEL_IP6_TC] = { .type = NLA_U8 }, 322 [LWTUNNEL_IP6_FLAGS] = { .type = NLA_U16 }, 323 }; 324 325 static int ip6_tun_build_state(struct net_device *dev, struct nlattr *attr, 326 unsigned int family, const void *cfg, 327 struct lwtunnel_state **ts) 328 { 329 struct ip_tunnel_info *tun_info; 330 struct lwtunnel_state *new_state; 331 struct nlattr *tb[LWTUNNEL_IP6_MAX + 1]; 332 int err; 333 334 err = nla_parse_nested(tb, LWTUNNEL_IP6_MAX, attr, ip6_tun_policy); 335 if (err < 0) 336 return err; 337 338 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 339 if (!new_state) 340 return -ENOMEM; 341 342 new_state->type = LWTUNNEL_ENCAP_IP6; 343 344 tun_info = lwt_tun_info(new_state); 345 346 if (tb[LWTUNNEL_IP6_ID]) 347 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP6_ID]); 348 349 if (tb[LWTUNNEL_IP6_DST]) 350 tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]); 351 352 if (tb[LWTUNNEL_IP6_SRC]) 353 tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]); 354 355 if (tb[LWTUNNEL_IP6_HOPLIMIT]) 356 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]); 357 358 if (tb[LWTUNNEL_IP6_TC]) 359 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]); 360 361 if (tb[LWTUNNEL_IP6_FLAGS]) 362 tun_info->key.tun_flags = nla_get_be16(tb[LWTUNNEL_IP6_FLAGS]); 363 364 tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6; 365 tun_info->options_len = 0; 366 367 *ts = new_state; 368 369 return 0; 370 } 371 372 static int ip6_tun_fill_encap_info(struct sk_buff *skb, 373 struct lwtunnel_state *lwtstate) 374 { 375 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 376 377 if (nla_put_be64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id, 378 LWTUNNEL_IP6_PAD) || 379 nla_put_in6_addr(skb, LWTUNNEL_IP6_DST, &tun_info->key.u.ipv6.dst) || 380 nla_put_in6_addr(skb, LWTUNNEL_IP6_SRC, &tun_info->key.u.ipv6.src) || 381 nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.tos) || 382 nla_put_u8(skb, LWTUNNEL_IP6_HOPLIMIT, tun_info->key.ttl) || 383 nla_put_be16(skb, LWTUNNEL_IP6_FLAGS, tun_info->key.tun_flags)) 384 return -ENOMEM; 385 386 return 0; 387 } 388 389 static int ip6_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 390 { 391 return nla_total_size_64bit(8) /* LWTUNNEL_IP6_ID */ 392 + nla_total_size(16) /* LWTUNNEL_IP6_DST */ 393 + nla_total_size(16) /* LWTUNNEL_IP6_SRC */ 394 + nla_total_size(1) /* LWTUNNEL_IP6_HOPLIMIT */ 395 + nla_total_size(1) /* LWTUNNEL_IP6_TC */ 396 + nla_total_size(2); /* LWTUNNEL_IP6_FLAGS */ 397 } 398 399 static const struct lwtunnel_encap_ops ip6_tun_lwt_ops = { 400 .build_state = ip6_tun_build_state, 401 .fill_encap = ip6_tun_fill_encap_info, 402 .get_encap_size = ip6_tun_encap_nlsize, 403 .cmp_encap = ip_tun_cmp_encap, 404 }; 405 406 void __init ip_tunnel_core_init(void) 407 { 408 /* If you land here, make sure whether increasing ip_tunnel_info's 409 * options_len is a reasonable choice with its usage in front ends 410 * (f.e., it's part of flow keys, etc). 411 */ 412 BUILD_BUG_ON(IP_TUNNEL_OPTS_MAX != 255); 413 414 lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP); 415 lwtunnel_encap_add_ops(&ip6_tun_lwt_ops, LWTUNNEL_ENCAP_IP6); 416 } 417 418 struct static_key ip_tunnel_metadata_cnt = STATIC_KEY_INIT_FALSE; 419 EXPORT_SYMBOL(ip_tunnel_metadata_cnt); 420 421 void ip_tunnel_need_metadata(void) 422 { 423 static_key_slow_inc(&ip_tunnel_metadata_cnt); 424 } 425 EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata); 426 427 void ip_tunnel_unneed_metadata(void) 428 { 429 static_key_slow_dec(&ip_tunnel_metadata_cnt); 430 } 431 EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata); 432