1 #ifndef __NET_IP_TUNNELS_H 2 #define __NET_IP_TUNNELS_H 1 3 4 #include <linux/if_tunnel.h> 5 #include <linux/netdevice.h> 6 #include <linux/skbuff.h> 7 #include <linux/socket.h> 8 #include <linux/types.h> 9 #include <linux/u64_stats_sync.h> 10 #include <linux/bitops.h> 11 12 #include <net/dsfield.h> 13 #include <net/gro_cells.h> 14 #include <net/inet_ecn.h> 15 #include <net/netns/generic.h> 16 #include <net/rtnetlink.h> 17 #include <net/lwtunnel.h> 18 #include <net/dst_cache.h> 19 20 #if IS_ENABLED(CONFIG_IPV6) 21 #include <net/ipv6.h> 22 #include <net/ip6_fib.h> 23 #include <net/ip6_route.h> 24 #endif 25 26 /* Keep error state on tunnel for 30 sec */ 27 #define IPTUNNEL_ERR_TIMEO (30*HZ) 28 29 /* Used to memset ip_tunnel padding. */ 30 #define IP_TUNNEL_KEY_SIZE offsetofend(struct ip_tunnel_key, tp_dst) 31 32 /* Used to memset ipv4 address padding. */ 33 #define IP_TUNNEL_KEY_IPV4_PAD offsetofend(struct ip_tunnel_key, u.ipv4.dst) 34 #define IP_TUNNEL_KEY_IPV4_PAD_LEN \ 35 (FIELD_SIZEOF(struct ip_tunnel_key, u) - \ 36 FIELD_SIZEOF(struct ip_tunnel_key, u.ipv4)) 37 38 struct ip_tunnel_key { 39 __be64 tun_id; 40 union { 41 struct { 42 __be32 src; 43 __be32 dst; 44 } ipv4; 45 struct { 46 struct in6_addr src; 47 struct in6_addr dst; 48 } ipv6; 49 } u; 50 __be16 tun_flags; 51 u8 tos; /* TOS for IPv4, TC for IPv6 */ 52 u8 ttl; /* TTL for IPv4, HL for IPv6 */ 53 __be32 label; /* Flow Label for IPv6 */ 54 __be16 tp_src; 55 __be16 tp_dst; 56 }; 57 58 /* Flags for ip_tunnel_info mode. */ 59 #define IP_TUNNEL_INFO_TX 0x01 /* represents tx tunnel parameters */ 60 #define IP_TUNNEL_INFO_IPV6 0x02 /* key contains IPv6 addresses */ 61 62 /* Maximum tunnel options length. */ 63 #define IP_TUNNEL_OPTS_MAX \ 64 GENMASK((FIELD_SIZEOF(struct ip_tunnel_info, \ 65 options_len) * BITS_PER_BYTE) - 1, 0) 66 67 struct ip_tunnel_info { 68 struct ip_tunnel_key key; 69 #ifdef CONFIG_DST_CACHE 70 struct dst_cache dst_cache; 71 #endif 72 u8 options_len; 73 u8 mode; 74 }; 75 76 /* 6rd prefix/relay information */ 77 #ifdef CONFIG_IPV6_SIT_6RD 78 struct ip_tunnel_6rd_parm { 79 struct in6_addr prefix; 80 __be32 relay_prefix; 81 u16 prefixlen; 82 u16 relay_prefixlen; 83 }; 84 #endif 85 86 struct ip_tunnel_encap { 87 u16 type; 88 u16 flags; 89 __be16 sport; 90 __be16 dport; 91 }; 92 93 struct ip_tunnel_prl_entry { 94 struct ip_tunnel_prl_entry __rcu *next; 95 __be32 addr; 96 u16 flags; 97 struct rcu_head rcu_head; 98 }; 99 100 struct metadata_dst; 101 102 struct ip_tunnel { 103 struct ip_tunnel __rcu *next; 104 struct hlist_node hash_node; 105 struct net_device *dev; 106 struct net *net; /* netns for packet i/o */ 107 108 unsigned long err_time; /* Time when the last ICMP error 109 * arrived */ 110 int err_count; /* Number of arrived ICMP errors */ 111 112 /* These four fields used only by GRE */ 113 u32 i_seqno; /* The last seen seqno */ 114 u32 o_seqno; /* The last output seqno */ 115 int tun_hlen; /* Precalculated header length */ 116 117 struct dst_cache dst_cache; 118 119 struct ip_tunnel_parm parms; 120 121 int mlink; 122 int encap_hlen; /* Encap header length (FOU,GUE) */ 123 int hlen; /* tun_hlen + encap_hlen */ 124 struct ip_tunnel_encap encap; 125 126 /* for SIT */ 127 #ifdef CONFIG_IPV6_SIT_6RD 128 struct ip_tunnel_6rd_parm ip6rd; 129 #endif 130 struct ip_tunnel_prl_entry __rcu *prl; /* potential router list */ 131 unsigned int prl_count; /* # of entries in PRL */ 132 unsigned int ip_tnl_net_id; 133 struct gro_cells gro_cells; 134 bool collect_md; 135 bool ignore_df; 136 }; 137 138 #define TUNNEL_CSUM __cpu_to_be16(0x01) 139 #define TUNNEL_ROUTING __cpu_to_be16(0x02) 140 #define TUNNEL_KEY __cpu_to_be16(0x04) 141 #define TUNNEL_SEQ __cpu_to_be16(0x08) 142 #define TUNNEL_STRICT __cpu_to_be16(0x10) 143 #define TUNNEL_REC __cpu_to_be16(0x20) 144 #define TUNNEL_VERSION __cpu_to_be16(0x40) 145 #define TUNNEL_NO_KEY __cpu_to_be16(0x80) 146 #define TUNNEL_DONT_FRAGMENT __cpu_to_be16(0x0100) 147 #define TUNNEL_OAM __cpu_to_be16(0x0200) 148 #define TUNNEL_CRIT_OPT __cpu_to_be16(0x0400) 149 #define TUNNEL_GENEVE_OPT __cpu_to_be16(0x0800) 150 #define TUNNEL_VXLAN_OPT __cpu_to_be16(0x1000) 151 #define TUNNEL_NOCACHE __cpu_to_be16(0x2000) 152 153 #define TUNNEL_OPTIONS_PRESENT (TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT) 154 155 struct tnl_ptk_info { 156 __be16 flags; 157 __be16 proto; 158 __be32 key; 159 __be32 seq; 160 int hdr_len; 161 }; 162 163 #define PACKET_RCVD 0 164 #define PACKET_REJECT 1 165 #define PACKET_NEXT 2 166 167 #define IP_TNL_HASH_BITS 7 168 #define IP_TNL_HASH_SIZE (1 << IP_TNL_HASH_BITS) 169 170 struct ip_tunnel_net { 171 struct net_device *fb_tunnel_dev; 172 struct hlist_head tunnels[IP_TNL_HASH_SIZE]; 173 struct ip_tunnel __rcu *collect_md_tun; 174 }; 175 176 static inline void ip_tunnel_key_init(struct ip_tunnel_key *key, 177 __be32 saddr, __be32 daddr, 178 u8 tos, u8 ttl, __be32 label, 179 __be16 tp_src, __be16 tp_dst, 180 __be64 tun_id, __be16 tun_flags) 181 { 182 key->tun_id = tun_id; 183 key->u.ipv4.src = saddr; 184 key->u.ipv4.dst = daddr; 185 memset((unsigned char *)key + IP_TUNNEL_KEY_IPV4_PAD, 186 0, IP_TUNNEL_KEY_IPV4_PAD_LEN); 187 key->tos = tos; 188 key->ttl = ttl; 189 key->label = label; 190 key->tun_flags = tun_flags; 191 192 /* For the tunnel types on the top of IPsec, the tp_src and tp_dst of 193 * the upper tunnel are used. 194 * E.g: GRE over IPSEC, the tp_src and tp_port are zero. 195 */ 196 key->tp_src = tp_src; 197 key->tp_dst = tp_dst; 198 199 /* Clear struct padding. */ 200 if (sizeof(*key) != IP_TUNNEL_KEY_SIZE) 201 memset((unsigned char *)key + IP_TUNNEL_KEY_SIZE, 202 0, sizeof(*key) - IP_TUNNEL_KEY_SIZE); 203 } 204 205 static inline bool 206 ip_tunnel_dst_cache_usable(const struct sk_buff *skb, 207 const struct ip_tunnel_info *info) 208 { 209 if (skb->mark) 210 return false; 211 if (!info) 212 return true; 213 if (info->key.tun_flags & TUNNEL_NOCACHE) 214 return false; 215 216 return true; 217 } 218 219 static inline unsigned short ip_tunnel_info_af(const struct ip_tunnel_info 220 *tun_info) 221 { 222 return tun_info->mode & IP_TUNNEL_INFO_IPV6 ? AF_INET6 : AF_INET; 223 } 224 225 static inline __be64 key32_to_tunnel_id(__be32 key) 226 { 227 #ifdef __BIG_ENDIAN 228 return (__force __be64)key; 229 #else 230 return (__force __be64)((__force u64)key << 32); 231 #endif 232 } 233 234 /* Returns the least-significant 32 bits of a __be64. */ 235 static inline __be32 tunnel_id_to_key32(__be64 tun_id) 236 { 237 #ifdef __BIG_ENDIAN 238 return (__force __be32)tun_id; 239 #else 240 return (__force __be32)((__force u64)tun_id >> 32); 241 #endif 242 } 243 244 #ifdef CONFIG_INET 245 246 int ip_tunnel_init(struct net_device *dev); 247 void ip_tunnel_uninit(struct net_device *dev); 248 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head); 249 struct net *ip_tunnel_get_link_net(const struct net_device *dev); 250 int ip_tunnel_get_iflink(const struct net_device *dev); 251 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id, 252 struct rtnl_link_ops *ops, char *devname); 253 254 void ip_tunnel_delete_net(struct ip_tunnel_net *itn, struct rtnl_link_ops *ops); 255 256 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 257 const struct iphdr *tnl_params, const u8 protocol); 258 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 259 const u8 proto); 260 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd); 261 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict); 262 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu); 263 264 struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev, 265 struct rtnl_link_stats64 *tot); 266 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn, 267 int link, __be16 flags, 268 __be32 remote, __be32 local, 269 __be32 key); 270 271 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb, 272 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst, 273 bool log_ecn_error); 274 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[], 275 struct ip_tunnel_parm *p); 276 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], 277 struct ip_tunnel_parm *p); 278 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id); 279 280 struct ip_tunnel_encap_ops { 281 size_t (*encap_hlen)(struct ip_tunnel_encap *e); 282 int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e, 283 u8 *protocol, struct flowi4 *fl4); 284 }; 285 286 #define MAX_IPTUN_ENCAP_OPS 8 287 288 extern const struct ip_tunnel_encap_ops __rcu * 289 iptun_encaps[MAX_IPTUN_ENCAP_OPS]; 290 291 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op, 292 unsigned int num); 293 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op, 294 unsigned int num); 295 296 int ip_tunnel_encap_setup(struct ip_tunnel *t, 297 struct ip_tunnel_encap *ipencap); 298 299 static inline int ip_encap_hlen(struct ip_tunnel_encap *e) 300 { 301 const struct ip_tunnel_encap_ops *ops; 302 int hlen = -EINVAL; 303 304 if (e->type == TUNNEL_ENCAP_NONE) 305 return 0; 306 307 if (e->type >= MAX_IPTUN_ENCAP_OPS) 308 return -EINVAL; 309 310 rcu_read_lock(); 311 ops = rcu_dereference(iptun_encaps[e->type]); 312 if (likely(ops && ops->encap_hlen)) 313 hlen = ops->encap_hlen(e); 314 rcu_read_unlock(); 315 316 return hlen; 317 } 318 319 static inline int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t, 320 u8 *protocol, struct flowi4 *fl4) 321 { 322 const struct ip_tunnel_encap_ops *ops; 323 int ret = -EINVAL; 324 325 if (t->encap.type == TUNNEL_ENCAP_NONE) 326 return 0; 327 328 if (t->encap.type >= MAX_IPTUN_ENCAP_OPS) 329 return -EINVAL; 330 331 rcu_read_lock(); 332 ops = rcu_dereference(iptun_encaps[t->encap.type]); 333 if (likely(ops && ops->build_header)) 334 ret = ops->build_header(skb, &t->encap, protocol, fl4); 335 rcu_read_unlock(); 336 337 return ret; 338 } 339 340 /* Extract dsfield from inner protocol */ 341 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph, 342 const struct sk_buff *skb) 343 { 344 if (skb->protocol == htons(ETH_P_IP)) 345 return iph->tos; 346 else if (skb->protocol == htons(ETH_P_IPV6)) 347 return ipv6_get_dsfield((const struct ipv6hdr *)iph); 348 else 349 return 0; 350 } 351 352 /* Propogate ECN bits out */ 353 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph, 354 const struct sk_buff *skb) 355 { 356 u8 inner = ip_tunnel_get_dsfield(iph, skb); 357 358 return INET_ECN_encapsulate(tos, inner); 359 } 360 361 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len, 362 __be16 inner_proto, bool raw_proto, bool xnet); 363 364 static inline int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, 365 __be16 inner_proto, bool xnet) 366 { 367 return __iptunnel_pull_header(skb, hdr_len, inner_proto, false, xnet); 368 } 369 370 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, 371 __be32 src, __be32 dst, u8 proto, 372 u8 tos, u8 ttl, __be16 df, bool xnet); 373 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md, 374 gfp_t flags); 375 376 int iptunnel_handle_offloads(struct sk_buff *skb, int gso_type_mask); 377 378 static inline int iptunnel_pull_offloads(struct sk_buff *skb) 379 { 380 if (skb_is_gso(skb)) { 381 int err; 382 383 err = skb_unclone(skb, GFP_ATOMIC); 384 if (unlikely(err)) 385 return err; 386 skb_shinfo(skb)->gso_type &= ~(NETIF_F_GSO_ENCAP_ALL >> 387 NETIF_F_GSO_SHIFT); 388 } 389 390 skb->encapsulation = 0; 391 return 0; 392 } 393 394 static inline void iptunnel_xmit_stats(struct net_device *dev, int pkt_len) 395 { 396 if (pkt_len > 0) { 397 struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats); 398 399 u64_stats_update_begin(&tstats->syncp); 400 tstats->tx_bytes += pkt_len; 401 tstats->tx_packets++; 402 u64_stats_update_end(&tstats->syncp); 403 put_cpu_ptr(tstats); 404 } else { 405 struct net_device_stats *err_stats = &dev->stats; 406 407 if (pkt_len < 0) { 408 err_stats->tx_errors++; 409 err_stats->tx_aborted_errors++; 410 } else { 411 err_stats->tx_dropped++; 412 } 413 } 414 } 415 416 static inline void *ip_tunnel_info_opts(struct ip_tunnel_info *info) 417 { 418 return info + 1; 419 } 420 421 static inline void ip_tunnel_info_opts_get(void *to, 422 const struct ip_tunnel_info *info) 423 { 424 memcpy(to, info + 1, info->options_len); 425 } 426 427 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info, 428 const void *from, int len) 429 { 430 memcpy(ip_tunnel_info_opts(info), from, len); 431 info->options_len = len; 432 } 433 434 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate) 435 { 436 return (struct ip_tunnel_info *)lwtstate->data; 437 } 438 439 extern struct static_key ip_tunnel_metadata_cnt; 440 441 /* Returns > 0 if metadata should be collected */ 442 static inline int ip_tunnel_collect_metadata(void) 443 { 444 return static_key_false(&ip_tunnel_metadata_cnt); 445 } 446 447 void __init ip_tunnel_core_init(void); 448 449 void ip_tunnel_need_metadata(void); 450 void ip_tunnel_unneed_metadata(void); 451 452 #else /* CONFIG_INET */ 453 454 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate) 455 { 456 return NULL; 457 } 458 459 static inline void ip_tunnel_need_metadata(void) 460 { 461 } 462 463 static inline void ip_tunnel_unneed_metadata(void) 464 { 465 } 466 467 static inline void ip_tunnel_info_opts_get(void *to, 468 const struct ip_tunnel_info *info) 469 { 470 } 471 472 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info, 473 const void *from, int len) 474 { 475 info->options_len = 0; 476 } 477 478 #endif /* CONFIG_INET */ 479 480 #endif /* __NET_IP_TUNNELS_H */ 481