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/arp.h> 41 #include <net/checksum.h> 42 #include <net/dsfield.h> 43 #include <net/inet_ecn.h> 44 #include <net/xfrm.h> 45 #include <net/net_namespace.h> 46 #include <net/netns/generic.h> 47 #include <net/rtnetlink.h> 48 #include <net/dst_metadata.h> 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(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 = 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 if (unlikely(net_xmit_eval(err))) 84 pkt_len = 0; 85 iptunnel_xmit_stats(dev, pkt_len); 86 } 87 EXPORT_SYMBOL_GPL(iptunnel_xmit); 88 89 int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto, 90 bool xnet) 91 { 92 if (unlikely(!pskb_may_pull(skb, hdr_len))) 93 return -ENOMEM; 94 95 skb_pull_rcsum(skb, hdr_len); 96 97 if (inner_proto == htons(ETH_P_TEB)) { 98 struct ethhdr *eh; 99 100 if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) 101 return -ENOMEM; 102 103 eh = (struct ethhdr *)skb->data; 104 if (likely(eth_proto_is_802_3(eh->h_proto))) 105 skb->protocol = eh->h_proto; 106 else 107 skb->protocol = htons(ETH_P_802_2); 108 109 } else { 110 skb->protocol = inner_proto; 111 } 112 113 skb_clear_hash_if_not_l4(skb); 114 skb->vlan_tci = 0; 115 skb_set_queue_mapping(skb, 0); 116 skb_scrub_packet(skb, xnet); 117 118 return iptunnel_pull_offloads(skb); 119 } 120 EXPORT_SYMBOL_GPL(iptunnel_pull_header); 121 122 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md, 123 gfp_t flags) 124 { 125 struct metadata_dst *res; 126 struct ip_tunnel_info *dst, *src; 127 128 if (!md || md->u.tun_info.mode & IP_TUNNEL_INFO_TX) 129 return NULL; 130 131 res = metadata_dst_alloc(0, flags); 132 if (!res) 133 return NULL; 134 135 dst = &res->u.tun_info; 136 src = &md->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->mode = src->mode | IP_TUNNEL_INFO_TX; 144 145 return res; 146 } 147 EXPORT_SYMBOL_GPL(iptunnel_metadata_reply); 148 149 struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb, 150 int gso_type_mask) 151 { 152 int err; 153 154 if (likely(!skb->encapsulation)) { 155 skb_reset_inner_headers(skb); 156 skb->encapsulation = 1; 157 } 158 159 if (skb_is_gso(skb)) { 160 err = skb_unclone(skb, GFP_ATOMIC); 161 if (unlikely(err)) 162 goto error; 163 skb_shinfo(skb)->gso_type |= gso_type_mask; 164 return skb; 165 } 166 167 if (skb->ip_summed != CHECKSUM_PARTIAL) { 168 skb->ip_summed = CHECKSUM_NONE; 169 /* We clear encapsulation here to prevent badly-written 170 * drivers potentially deciding to offload an inner checksum 171 * if we set CHECKSUM_PARTIAL on the outer header. 172 * This should go away when the drivers are all fixed. 173 */ 174 skb->encapsulation = 0; 175 } 176 177 return skb; 178 error: 179 kfree_skb(skb); 180 return ERR_PTR(err); 181 } 182 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); 183 184 /* Often modified stats are per cpu, other are shared (netdev->stats) */ 185 struct rtnl_link_stats64 *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 return tot; 213 } 214 EXPORT_SYMBOL_GPL(ip_tunnel_get_stats64); 215 216 static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = { 217 [LWTUNNEL_IP_ID] = { .type = NLA_U64 }, 218 [LWTUNNEL_IP_DST] = { .type = NLA_U32 }, 219 [LWTUNNEL_IP_SRC] = { .type = NLA_U32 }, 220 [LWTUNNEL_IP_TTL] = { .type = NLA_U8 }, 221 [LWTUNNEL_IP_TOS] = { .type = NLA_U8 }, 222 [LWTUNNEL_IP_FLAGS] = { .type = NLA_U16 }, 223 }; 224 225 static int ip_tun_build_state(struct net_device *dev, struct nlattr *attr, 226 unsigned int family, const void *cfg, 227 struct lwtunnel_state **ts) 228 { 229 struct ip_tunnel_info *tun_info; 230 struct lwtunnel_state *new_state; 231 struct nlattr *tb[LWTUNNEL_IP_MAX + 1]; 232 int err; 233 234 err = nla_parse_nested(tb, LWTUNNEL_IP_MAX, attr, ip_tun_policy); 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 if (tb[LWTUNNEL_IP_ID]) 247 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP_ID]); 248 249 if (tb[LWTUNNEL_IP_DST]) 250 tun_info->key.u.ipv4.dst = nla_get_be32(tb[LWTUNNEL_IP_DST]); 251 252 if (tb[LWTUNNEL_IP_SRC]) 253 tun_info->key.u.ipv4.src = nla_get_be32(tb[LWTUNNEL_IP_SRC]); 254 255 if (tb[LWTUNNEL_IP_TTL]) 256 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]); 257 258 if (tb[LWTUNNEL_IP_TOS]) 259 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]); 260 261 if (tb[LWTUNNEL_IP_FLAGS]) 262 tun_info->key.tun_flags = nla_get_be16(tb[LWTUNNEL_IP_FLAGS]); 263 264 tun_info->mode = IP_TUNNEL_INFO_TX; 265 tun_info->options_len = 0; 266 267 *ts = new_state; 268 269 return 0; 270 } 271 272 static int ip_tun_fill_encap_info(struct sk_buff *skb, 273 struct lwtunnel_state *lwtstate) 274 { 275 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 276 277 if (nla_put_be64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id) || 278 nla_put_be32(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) || 279 nla_put_be32(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) || 280 nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) || 281 nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) || 282 nla_put_be16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags)) 283 return -ENOMEM; 284 285 return 0; 286 } 287 288 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 289 { 290 return nla_total_size(8) /* LWTUNNEL_IP_ID */ 291 + nla_total_size(4) /* LWTUNNEL_IP_DST */ 292 + nla_total_size(4) /* LWTUNNEL_IP_SRC */ 293 + nla_total_size(1) /* LWTUNNEL_IP_TOS */ 294 + nla_total_size(1) /* LWTUNNEL_IP_TTL */ 295 + nla_total_size(2); /* LWTUNNEL_IP_FLAGS */ 296 } 297 298 static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b) 299 { 300 return memcmp(lwt_tun_info(a), lwt_tun_info(b), 301 sizeof(struct ip_tunnel_info)); 302 } 303 304 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = { 305 .build_state = ip_tun_build_state, 306 .fill_encap = ip_tun_fill_encap_info, 307 .get_encap_size = ip_tun_encap_nlsize, 308 .cmp_encap = ip_tun_cmp_encap, 309 }; 310 311 static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = { 312 [LWTUNNEL_IP6_ID] = { .type = NLA_U64 }, 313 [LWTUNNEL_IP6_DST] = { .len = sizeof(struct in6_addr) }, 314 [LWTUNNEL_IP6_SRC] = { .len = sizeof(struct in6_addr) }, 315 [LWTUNNEL_IP6_HOPLIMIT] = { .type = NLA_U8 }, 316 [LWTUNNEL_IP6_TC] = { .type = NLA_U8 }, 317 [LWTUNNEL_IP6_FLAGS] = { .type = NLA_U16 }, 318 }; 319 320 static int ip6_tun_build_state(struct net_device *dev, struct nlattr *attr, 321 unsigned int family, const void *cfg, 322 struct lwtunnel_state **ts) 323 { 324 struct ip_tunnel_info *tun_info; 325 struct lwtunnel_state *new_state; 326 struct nlattr *tb[LWTUNNEL_IP6_MAX + 1]; 327 int err; 328 329 err = nla_parse_nested(tb, LWTUNNEL_IP6_MAX, attr, ip6_tun_policy); 330 if (err < 0) 331 return err; 332 333 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 334 if (!new_state) 335 return -ENOMEM; 336 337 new_state->type = LWTUNNEL_ENCAP_IP6; 338 339 tun_info = lwt_tun_info(new_state); 340 341 if (tb[LWTUNNEL_IP6_ID]) 342 tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP6_ID]); 343 344 if (tb[LWTUNNEL_IP6_DST]) 345 tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]); 346 347 if (tb[LWTUNNEL_IP6_SRC]) 348 tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]); 349 350 if (tb[LWTUNNEL_IP6_HOPLIMIT]) 351 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]); 352 353 if (tb[LWTUNNEL_IP6_TC]) 354 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]); 355 356 if (tb[LWTUNNEL_IP6_FLAGS]) 357 tun_info->key.tun_flags = nla_get_be16(tb[LWTUNNEL_IP6_FLAGS]); 358 359 tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6; 360 tun_info->options_len = 0; 361 362 *ts = new_state; 363 364 return 0; 365 } 366 367 static int ip6_tun_fill_encap_info(struct sk_buff *skb, 368 struct lwtunnel_state *lwtstate) 369 { 370 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 371 372 if (nla_put_be64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id) || 373 nla_put_in6_addr(skb, LWTUNNEL_IP6_DST, &tun_info->key.u.ipv6.dst) || 374 nla_put_in6_addr(skb, LWTUNNEL_IP6_SRC, &tun_info->key.u.ipv6.src) || 375 nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.tos) || 376 nla_put_u8(skb, LWTUNNEL_IP6_HOPLIMIT, tun_info->key.ttl) || 377 nla_put_be16(skb, LWTUNNEL_IP6_FLAGS, tun_info->key.tun_flags)) 378 return -ENOMEM; 379 380 return 0; 381 } 382 383 static int ip6_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 384 { 385 return nla_total_size(8) /* LWTUNNEL_IP6_ID */ 386 + nla_total_size(16) /* LWTUNNEL_IP6_DST */ 387 + nla_total_size(16) /* LWTUNNEL_IP6_SRC */ 388 + nla_total_size(1) /* LWTUNNEL_IP6_HOPLIMIT */ 389 + nla_total_size(1) /* LWTUNNEL_IP6_TC */ 390 + nla_total_size(2); /* LWTUNNEL_IP6_FLAGS */ 391 } 392 393 static const struct lwtunnel_encap_ops ip6_tun_lwt_ops = { 394 .build_state = ip6_tun_build_state, 395 .fill_encap = ip6_tun_fill_encap_info, 396 .get_encap_size = ip6_tun_encap_nlsize, 397 .cmp_encap = ip_tun_cmp_encap, 398 }; 399 400 void __init ip_tunnel_core_init(void) 401 { 402 /* If you land here, make sure whether increasing ip_tunnel_info's 403 * options_len is a reasonable choice with its usage in front ends 404 * (f.e., it's part of flow keys, etc). 405 */ 406 BUILD_BUG_ON(IP_TUNNEL_OPTS_MAX != 255); 407 408 lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP); 409 lwtunnel_encap_add_ops(&ip6_tun_lwt_ops, LWTUNNEL_ENCAP_IP6); 410 } 411 412 struct static_key ip_tunnel_metadata_cnt = STATIC_KEY_INIT_FALSE; 413 EXPORT_SYMBOL(ip_tunnel_metadata_cnt); 414 415 void ip_tunnel_need_metadata(void) 416 { 417 static_key_slow_inc(&ip_tunnel_metadata_cnt); 418 } 419 EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata); 420 421 void ip_tunnel_unneed_metadata(void) 422 { 423 static_key_slow_dec(&ip_tunnel_metadata_cnt); 424 } 425 EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata); 426