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 int 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 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(net, iph, skb_shinfo(skb)->gso_segs ?: 1); 80 81 err = ip_local_out(net, sk, skb); 82 if (unlikely(net_xmit_eval(err))) 83 pkt_len = 0; 84 return pkt_len; 85 } 86 EXPORT_SYMBOL_GPL(iptunnel_xmit); 87 88 int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto) 89 { 90 if (unlikely(!pskb_may_pull(skb, hdr_len))) 91 return -ENOMEM; 92 93 skb_pull_rcsum(skb, hdr_len); 94 95 if (inner_proto == htons(ETH_P_TEB)) { 96 struct ethhdr *eh; 97 98 if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) 99 return -ENOMEM; 100 101 eh = (struct ethhdr *)skb->data; 102 if (likely(eth_proto_is_802_3(eh->h_proto))) 103 skb->protocol = eh->h_proto; 104 else 105 skb->protocol = htons(ETH_P_802_2); 106 107 } else { 108 skb->protocol = inner_proto; 109 } 110 111 nf_reset(skb); 112 secpath_reset(skb); 113 skb_clear_hash_if_not_l4(skb); 114 skb_dst_drop(skb); 115 skb->vlan_tci = 0; 116 skb_set_queue_mapping(skb, 0); 117 skb->pkt_type = PACKET_HOST; 118 return 0; 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 bool csum_help, 151 int gso_type_mask) 152 { 153 int err; 154 155 if (likely(!skb->encapsulation)) { 156 skb_reset_inner_headers(skb); 157 skb->encapsulation = 1; 158 } 159 160 if (skb_is_gso(skb)) { 161 err = skb_unclone(skb, GFP_ATOMIC); 162 if (unlikely(err)) 163 goto error; 164 skb_shinfo(skb)->gso_type |= gso_type_mask; 165 return skb; 166 } 167 168 /* If packet is not gso and we are resolving any partial checksum, 169 * clear encapsulation flag. This allows setting CHECKSUM_PARTIAL 170 * on the outer header without confusing devices that implement 171 * NETIF_F_IP_CSUM with encapsulation. 172 */ 173 if (csum_help) 174 skb->encapsulation = 0; 175 176 if (skb->ip_summed == CHECKSUM_PARTIAL && csum_help) { 177 err = skb_checksum_help(skb); 178 if (unlikely(err)) 179 goto error; 180 } else if (skb->ip_summed != CHECKSUM_PARTIAL) 181 skb->ip_summed = CHECKSUM_NONE; 182 183 return skb; 184 error: 185 kfree_skb(skb); 186 return ERR_PTR(err); 187 } 188 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); 189 190 /* Often modified stats are per cpu, other are shared (netdev->stats) */ 191 struct rtnl_link_stats64 *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 return tot; 219 } 220 EXPORT_SYMBOL_GPL(ip_tunnel_get_stats64); 221 222 static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = { 223 [LWTUNNEL_IP_ID] = { .type = NLA_U64 }, 224 [LWTUNNEL_IP_DST] = { .type = NLA_U32 }, 225 [LWTUNNEL_IP_SRC] = { .type = NLA_U32 }, 226 [LWTUNNEL_IP_TTL] = { .type = NLA_U8 }, 227 [LWTUNNEL_IP_TOS] = { .type = NLA_U8 }, 228 [LWTUNNEL_IP_FLAGS] = { .type = NLA_U16 }, 229 }; 230 231 static int ip_tun_build_state(struct net_device *dev, struct nlattr *attr, 232 unsigned int family, const void *cfg, 233 struct lwtunnel_state **ts) 234 { 235 struct ip_tunnel_info *tun_info; 236 struct lwtunnel_state *new_state; 237 struct nlattr *tb[LWTUNNEL_IP_MAX + 1]; 238 int err; 239 240 err = nla_parse_nested(tb, LWTUNNEL_IP_MAX, attr, ip_tun_policy); 241 if (err < 0) 242 return err; 243 244 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 245 if (!new_state) 246 return -ENOMEM; 247 248 new_state->type = LWTUNNEL_ENCAP_IP; 249 250 tun_info = lwt_tun_info(new_state); 251 252 if (tb[LWTUNNEL_IP_ID]) 253 tun_info->key.tun_id = nla_get_u64(tb[LWTUNNEL_IP_ID]); 254 255 if (tb[LWTUNNEL_IP_DST]) 256 tun_info->key.u.ipv4.dst = nla_get_be32(tb[LWTUNNEL_IP_DST]); 257 258 if (tb[LWTUNNEL_IP_SRC]) 259 tun_info->key.u.ipv4.src = nla_get_be32(tb[LWTUNNEL_IP_SRC]); 260 261 if (tb[LWTUNNEL_IP_TTL]) 262 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]); 263 264 if (tb[LWTUNNEL_IP_TOS]) 265 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]); 266 267 if (tb[LWTUNNEL_IP_FLAGS]) 268 tun_info->key.tun_flags = nla_get_u16(tb[LWTUNNEL_IP_FLAGS]); 269 270 tun_info->mode = IP_TUNNEL_INFO_TX; 271 tun_info->options_len = 0; 272 273 *ts = new_state; 274 275 return 0; 276 } 277 278 static int ip_tun_fill_encap_info(struct sk_buff *skb, 279 struct lwtunnel_state *lwtstate) 280 { 281 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 282 283 if (nla_put_u64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id) || 284 nla_put_be32(skb, LWTUNNEL_IP_DST, tun_info->key.u.ipv4.dst) || 285 nla_put_be32(skb, LWTUNNEL_IP_SRC, tun_info->key.u.ipv4.src) || 286 nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.tos) || 287 nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ttl) || 288 nla_put_u16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags)) 289 return -ENOMEM; 290 291 return 0; 292 } 293 294 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 295 { 296 return nla_total_size(8) /* LWTUNNEL_IP_ID */ 297 + nla_total_size(4) /* LWTUNNEL_IP_DST */ 298 + nla_total_size(4) /* LWTUNNEL_IP_SRC */ 299 + nla_total_size(1) /* LWTUNNEL_IP_TOS */ 300 + nla_total_size(1) /* LWTUNNEL_IP_TTL */ 301 + nla_total_size(2); /* LWTUNNEL_IP_FLAGS */ 302 } 303 304 static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b) 305 { 306 return memcmp(lwt_tun_info(a), lwt_tun_info(b), 307 sizeof(struct ip_tunnel_info)); 308 } 309 310 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = { 311 .build_state = ip_tun_build_state, 312 .fill_encap = ip_tun_fill_encap_info, 313 .get_encap_size = ip_tun_encap_nlsize, 314 .cmp_encap = ip_tun_cmp_encap, 315 }; 316 317 static const struct nla_policy ip6_tun_policy[LWTUNNEL_IP6_MAX + 1] = { 318 [LWTUNNEL_IP6_ID] = { .type = NLA_U64 }, 319 [LWTUNNEL_IP6_DST] = { .len = sizeof(struct in6_addr) }, 320 [LWTUNNEL_IP6_SRC] = { .len = sizeof(struct in6_addr) }, 321 [LWTUNNEL_IP6_HOPLIMIT] = { .type = NLA_U8 }, 322 [LWTUNNEL_IP6_TC] = { .type = NLA_U8 }, 323 [LWTUNNEL_IP6_FLAGS] = { .type = NLA_U16 }, 324 }; 325 326 static int ip6_tun_build_state(struct net_device *dev, struct nlattr *attr, 327 unsigned int family, const void *cfg, 328 struct lwtunnel_state **ts) 329 { 330 struct ip_tunnel_info *tun_info; 331 struct lwtunnel_state *new_state; 332 struct nlattr *tb[LWTUNNEL_IP6_MAX + 1]; 333 int err; 334 335 err = nla_parse_nested(tb, LWTUNNEL_IP6_MAX, attr, ip6_tun_policy); 336 if (err < 0) 337 return err; 338 339 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 340 if (!new_state) 341 return -ENOMEM; 342 343 new_state->type = LWTUNNEL_ENCAP_IP6; 344 345 tun_info = lwt_tun_info(new_state); 346 347 if (tb[LWTUNNEL_IP6_ID]) 348 tun_info->key.tun_id = nla_get_u64(tb[LWTUNNEL_IP6_ID]); 349 350 if (tb[LWTUNNEL_IP6_DST]) 351 tun_info->key.u.ipv6.dst = nla_get_in6_addr(tb[LWTUNNEL_IP6_DST]); 352 353 if (tb[LWTUNNEL_IP6_SRC]) 354 tun_info->key.u.ipv6.src = nla_get_in6_addr(tb[LWTUNNEL_IP6_SRC]); 355 356 if (tb[LWTUNNEL_IP6_HOPLIMIT]) 357 tun_info->key.ttl = nla_get_u8(tb[LWTUNNEL_IP6_HOPLIMIT]); 358 359 if (tb[LWTUNNEL_IP6_TC]) 360 tun_info->key.tos = nla_get_u8(tb[LWTUNNEL_IP6_TC]); 361 362 if (tb[LWTUNNEL_IP6_FLAGS]) 363 tun_info->key.tun_flags = nla_get_u16(tb[LWTUNNEL_IP6_FLAGS]); 364 365 tun_info->mode = IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6; 366 tun_info->options_len = 0; 367 368 *ts = new_state; 369 370 return 0; 371 } 372 373 static int ip6_tun_fill_encap_info(struct sk_buff *skb, 374 struct lwtunnel_state *lwtstate) 375 { 376 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 377 378 if (nla_put_u64(skb, LWTUNNEL_IP6_ID, tun_info->key.tun_id) || 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_HOPLIMIT, tun_info->key.tos) || 382 nla_put_u8(skb, LWTUNNEL_IP6_TC, tun_info->key.ttl) || 383 nla_put_u16(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(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 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