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/mroute.h> 28 #include <linux/init.h> 29 #include <linux/in6.h> 30 #include <linux/inetdevice.h> 31 #include <linux/netfilter_ipv4.h> 32 #include <linux/etherdevice.h> 33 #include <linux/if_ether.h> 34 #include <linux/if_vlan.h> 35 #include <linux/static_key.h> 36 37 #include <net/ip.h> 38 #include <net/icmp.h> 39 #include <net/protocol.h> 40 #include <net/ip_tunnels.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 int iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, 52 __be32 src, __be32 dst, __u8 proto, 53 __u8 tos, __u8 ttl, __be16 df, bool xnet) 54 { 55 int pkt_len = skb->len - skb_inner_network_offset(skb); 56 struct iphdr *iph; 57 int err; 58 59 skb_scrub_packet(skb, xnet); 60 61 skb_clear_hash(skb); 62 skb_dst_set(skb, &rt->dst); 63 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 64 65 /* Push down and install the IP header. */ 66 skb_push(skb, sizeof(struct iphdr)); 67 skb_reset_network_header(skb); 68 69 iph = ip_hdr(skb); 70 71 iph->version = 4; 72 iph->ihl = sizeof(struct iphdr) >> 2; 73 iph->frag_off = df; 74 iph->protocol = proto; 75 iph->tos = tos; 76 iph->daddr = dst; 77 iph->saddr = src; 78 iph->ttl = ttl; 79 __ip_select_ident(dev_net(rt->dst.dev), iph, 80 skb_shinfo(skb)->gso_segs ?: 1); 81 82 err = ip_local_out_sk(sk, skb); 83 if (unlikely(net_xmit_eval(err))) 84 pkt_len = 0; 85 return 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 { 91 if (unlikely(!pskb_may_pull(skb, hdr_len))) 92 return -ENOMEM; 93 94 skb_pull_rcsum(skb, hdr_len); 95 96 if (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 nf_reset(skb); 113 secpath_reset(skb); 114 skb_clear_hash_if_not_l4(skb); 115 skb_dst_drop(skb); 116 skb->vlan_tci = 0; 117 skb_set_queue_mapping(skb, 0); 118 skb->pkt_type = PACKET_HOST; 119 return 0; 120 } 121 EXPORT_SYMBOL_GPL(iptunnel_pull_header); 122 123 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md, 124 gfp_t flags) 125 { 126 struct metadata_dst *res; 127 struct ip_tunnel_info *dst, *src; 128 129 if (!md || md->u.tun_info.mode & IP_TUNNEL_INFO_TX) 130 return NULL; 131 132 res = metadata_dst_alloc(0, flags); 133 if (!res) 134 return NULL; 135 136 dst = &res->u.tun_info; 137 src = &md->u.tun_info; 138 dst->key.tun_id = src->key.tun_id; 139 if (src->mode & IP_TUNNEL_INFO_IPV6) 140 memcpy(&dst->key.u.ipv6.dst, &src->key.u.ipv6.src, 141 sizeof(struct in6_addr)); 142 else 143 dst->key.u.ipv4.dst = src->key.u.ipv4.src; 144 dst->mode = src->mode | IP_TUNNEL_INFO_TX; 145 146 return res; 147 } 148 EXPORT_SYMBOL_GPL(iptunnel_metadata_reply); 149 150 struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb, 151 bool csum_help, 152 int gso_type_mask) 153 { 154 int err; 155 156 if (likely(!skb->encapsulation)) { 157 skb_reset_inner_headers(skb); 158 skb->encapsulation = 1; 159 } 160 161 if (skb_is_gso(skb)) { 162 err = skb_unclone(skb, GFP_ATOMIC); 163 if (unlikely(err)) 164 goto error; 165 skb_shinfo(skb)->gso_type |= gso_type_mask; 166 return skb; 167 } 168 169 /* If packet is not gso and we are resolving any partial checksum, 170 * clear encapsulation flag. This allows setting CHECKSUM_PARTIAL 171 * on the outer header without confusing devices that implement 172 * NETIF_F_IP_CSUM with encapsulation. 173 */ 174 if (csum_help) 175 skb->encapsulation = 0; 176 177 if (skb->ip_summed == CHECKSUM_PARTIAL && csum_help) { 178 err = skb_checksum_help(skb); 179 if (unlikely(err)) 180 goto error; 181 } else if (skb->ip_summed != CHECKSUM_PARTIAL) 182 skb->ip_summed = CHECKSUM_NONE; 183 184 return skb; 185 error: 186 kfree_skb(skb); 187 return ERR_PTR(err); 188 } 189 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); 190 191 /* Often modified stats are per cpu, other are shared (netdev->stats) */ 192 struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev, 193 struct rtnl_link_stats64 *tot) 194 { 195 int i; 196 197 netdev_stats_to_stats64(tot, &dev->stats); 198 199 for_each_possible_cpu(i) { 200 const struct pcpu_sw_netstats *tstats = 201 per_cpu_ptr(dev->tstats, i); 202 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 203 unsigned int start; 204 205 do { 206 start = u64_stats_fetch_begin_irq(&tstats->syncp); 207 rx_packets = tstats->rx_packets; 208 tx_packets = tstats->tx_packets; 209 rx_bytes = tstats->rx_bytes; 210 tx_bytes = tstats->tx_bytes; 211 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); 212 213 tot->rx_packets += rx_packets; 214 tot->tx_packets += tx_packets; 215 tot->rx_bytes += rx_bytes; 216 tot->tx_bytes += tx_bytes; 217 } 218 219 return tot; 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 net_device *dev, struct nlattr *attr, 233 unsigned int family, const void *cfg, 234 struct lwtunnel_state **ts) 235 { 236 struct ip_tunnel_info *tun_info; 237 struct lwtunnel_state *new_state; 238 struct nlattr *tb[LWTUNNEL_IP_MAX + 1]; 239 int err; 240 241 err = nla_parse_nested(tb, LWTUNNEL_IP_MAX, attr, ip_tun_policy); 242 if (err < 0) 243 return err; 244 245 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 246 if (!new_state) 247 return -ENOMEM; 248 249 new_state->type = LWTUNNEL_ENCAP_IP; 250 251 tun_info = lwt_tun_info(new_state); 252 253 if (tb[LWTUNNEL_IP_ID]) 254 tun_info->key.tun_id = nla_get_u64(tb[LWTUNNEL_IP_ID]); 255 256 if (tb[LWTUNNEL_IP_DST]) 257 tun_info->key.u.ipv4.dst = nla_get_be32(tb[LWTUNNEL_IP_DST]); 258 259 if (tb[LWTUNNEL_IP_SRC]) 260 tun_info->key.u.ipv4.src = nla_get_be32(tb[LWTUNNEL_IP_SRC]); 261 262 if (tb[LWTUNNEL_IP_TTL]) 263 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]); 264 265 if (tb[LWTUNNEL_IP_TOS]) 266 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]); 267 268 if (tb[LWTUNNEL_IP_FLAGS]) 269 tun_info->key.tun_flags = nla_get_u16(tb[LWTUNNEL_IP_FLAGS]); 270 271 tun_info->mode = IP_TUNNEL_INFO_TX; 272 tun_info->options_len = 0; 273 274 *ts = new_state; 275 276 return 0; 277 } 278 279 static int ip_tun_fill_encap_info(struct sk_buff *skb, 280 struct lwtunnel_state *lwtstate) 281 { 282 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 283 284 if (nla_put_u64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id) || 285 nla_put_be32(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) || 286 nla_put_be32(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) || 287 nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) || 288 nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) || 289 nla_put_u16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags)) 290 return -ENOMEM; 291 292 return 0; 293 } 294 295 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 296 { 297 return nla_total_size(8) /* LWTUNNEL_IP_ID */ 298 + nla_total_size(4) /* LWTUNNEL_IP_DST */ 299 + nla_total_size(4) /* LWTUNNEL_IP_SRC */ 300 + nla_total_size(1) /* LWTUNNEL_IP_TOS */ 301 + nla_total_size(1) /* LWTUNNEL_IP_TTL */ 302 + nla_total_size(2); /* LWTUNNEL_IP_FLAGS */ 303 } 304 305 static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b) 306 { 307 return memcmp(lwt_tun_info(a), lwt_tun_info(b), 308 sizeof(struct ip_tunnel_info)); 309 } 310 311 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = { 312 .build_state = ip_tun_build_state, 313 .fill_encap = ip_tun_fill_encap_info, 314 .get_encap_size = ip_tun_encap_nlsize, 315 .cmp_encap = ip_tun_cmp_encap, 316 }; 317 318 static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = { 319 [LWTUNNEL_IP6_ID] = { .type = NLA_U64 }, 320 [LWTUNNEL_IP6_DST] = { .len = sizeof(struct in6_addr) }, 321 [LWTUNNEL_IP6_SRC] = { .len = sizeof(struct in6_addr) }, 322 [LWTUNNEL_IP6_HOPLIMIT] = { .type = NLA_U8 }, 323 [LWTUNNEL_IP6_TC] = { .type = NLA_U8 }, 324 [LWTUNNEL_IP6_FLAGS] = { .type = NLA_U16 }, 325 }; 326 327 static int ip6_tun_build_state(struct net_device *dev, struct nlattr *attr, 328 unsigned int family, const void *cfg, 329 struct lwtunnel_state **ts) 330 { 331 struct ip_tunnel_info *tun_info; 332 struct lwtunnel_state *new_state; 333 struct nlattr *tb[LWTUNNEL_IP6_MAX + 1]; 334 int err; 335 336 err = nla_parse_nested(tb, LWTUNNEL_IP6_MAX, attr, ip6_tun_policy); 337 if (err < 0) 338 return err; 339 340 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 341 if (!new_state) 342 return -ENOMEM; 343 344 new_state->type = LWTUNNEL_ENCAP_IP6; 345 346 tun_info = lwt_tun_info(new_state); 347 348 if (tb[LWTUNNEL_IP6_ID]) 349 tun_info->key.tun_id = nla_get_u64(tb[LWTUNNEL_IP6_ID]); 350 351 if (tb[LWTUNNEL_IP6_DST]) 352 tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]); 353 354 if (tb[LWTUNNEL_IP6_SRC]) 355 tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]); 356 357 if (tb[LWTUNNEL_IP6_HOPLIMIT]) 358 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]); 359 360 if (tb[LWTUNNEL_IP6_TC]) 361 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]); 362 363 if (tb[LWTUNNEL_IP6_FLAGS]) 364 tun_info->key.tun_flags = nla_get_u16(tb[LWTUNNEL_IP6_FLAGS]); 365 366 tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6; 367 tun_info->options_len = 0; 368 369 *ts = new_state; 370 371 return 0; 372 } 373 374 static int ip6_tun_fill_encap_info(struct sk_buff *skb, 375 struct lwtunnel_state *lwtstate) 376 { 377 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 378 379 if (nla_put_u64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id) || 380 nla_put_in6_addr(skb, LWTUNNEL_IP6_DST, &tun_info->key.u.ipv6.dst) || 381 nla_put_in6_addr(skb, LWTUNNEL_IP6_SRC, &tun_info->key.u.ipv6.src) || 382 nla_put_u8(skb, LWTUNNEL_IP6_HOPLIMIT, tun_info->key.tos) || 383 nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.ttl) || 384 nla_put_u16(skb, LWTUNNEL_IP6_FLAGS, tun_info->key.tun_flags)) 385 return -ENOMEM; 386 387 return 0; 388 } 389 390 static int ip6_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 391 { 392 return nla_total_size(8) /* LWTUNNEL_IP6_ID */ 393 + nla_total_size(16) /* LWTUNNEL_IP6_DST */ 394 + nla_total_size(16) /* LWTUNNEL_IP6_SRC */ 395 + nla_total_size(1) /* LWTUNNEL_IP6_HOPLIMIT */ 396 + nla_total_size(1) /* LWTUNNEL_IP6_TC */ 397 + nla_total_size(2); /* LWTUNNEL_IP6_FLAGS */ 398 } 399 400 static const struct lwtunnel_encap_ops ip6_tun_lwt_ops = { 401 .build_state = ip6_tun_build_state, 402 .fill_encap = ip6_tun_fill_encap_info, 403 .get_encap_size = ip6_tun_encap_nlsize, 404 .cmp_encap = ip_tun_cmp_encap, 405 }; 406 407 void __init ip_tunnel_core_init(void) 408 { 409 lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP); 410 lwtunnel_encap_add_ops(&ip6_tun_lwt_ops, LWTUNNEL_ENCAP_IP6); 411 } 412 413 struct static_key ip_tunnel_metadata_cnt = STATIC_KEY_INIT_FALSE; 414 EXPORT_SYMBOL(ip_tunnel_metadata_cnt); 415 416 void ip_tunnel_need_metadata(void) 417 { 418 static_key_slow_inc(&ip_tunnel_metadata_cnt); 419 } 420 EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata); 421 422 void ip_tunnel_unneed_metadata(void) 423 { 424 static_key_slow_dec(&ip_tunnel_metadata_cnt); 425 } 426 EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata); 427