1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __NET_IP_TUNNELS_H 3 #define __NET_IP_TUNNELS_H 1 4 5 #include <linux/if_tunnel.h> 6 #include <linux/netdevice.h> 7 #include <linux/skbuff.h> 8 #include <linux/socket.h> 9 #include <linux/types.h> 10 #include <linux/u64_stats_sync.h> 11 #include <linux/bitops.h> 12 13 #include <net/dsfield.h> 14 #include <net/gro_cells.h> 15 #include <net/inet_ecn.h> 16 #include <net/netns/generic.h> 17 #include <net/rtnetlink.h> 18 #include <net/lwtunnel.h> 19 #include <net/dst_cache.h> 20 21 #if IS_ENABLED(CONFIG_IPV6) 22 #include <net/ipv6.h> 23 #include <net/ip6_fib.h> 24 #include <net/ip6_route.h> 25 #endif 26 27 /* Keep error state on tunnel for 30 sec */ 28 #define IPTUNNEL_ERR_TIMEO (30*HZ) 29 30 /* Used to memset ip_tunnel padding. */ 31 #define IP_TUNNEL_KEY_SIZE offsetofend(struct ip_tunnel_key, tp_dst) 32 33 /* Used to memset ipv4 address padding. */ 34 #define IP_TUNNEL_KEY_IPV4_PAD offsetofend(struct ip_tunnel_key, u.ipv4.dst) 35 #define IP_TUNNEL_KEY_IPV4_PAD_LEN \ 36 (FIELD_SIZEOF(struct ip_tunnel_key, u) - \ 37 FIELD_SIZEOF(struct ip_tunnel_key, u.ipv4)) 38 39 struct ip_tunnel_key { 40 __be64 tun_id; 41 union { 42 struct { 43 __be32 src; 44 __be32 dst; 45 } ipv4; 46 struct { 47 struct in6_addr src; 48 struct in6_addr dst; 49 } ipv6; 50 } u; 51 __be16 tun_flags; 52 u8 tos; /* TOS for IPv4, TC for IPv6 */ 53 u8 ttl; /* TTL for IPv4, HL for IPv6 */ 54 __be32 label; /* Flow Label for IPv6 */ 55 __be16 tp_src; 56 __be16 tp_dst; 57 }; 58 59 /* Flags for ip_tunnel_info mode. */ 60 #define IP_TUNNEL_INFO_TX 0x01 /* represents tx tunnel parameters */ 61 #define IP_TUNNEL_INFO_IPV6 0x02 /* key contains IPv6 addresses */ 62 #define IP_TUNNEL_INFO_BRIDGE 0x04 /* represents a bridged tunnel id */ 63 64 /* Maximum tunnel options length. */ 65 #define IP_TUNNEL_OPTS_MAX \ 66 GENMASK((FIELD_SIZEOF(struct ip_tunnel_info, \ 67 options_len) * BITS_PER_BYTE) - 1, 0) 68 69 struct ip_tunnel_info { 70 struct ip_tunnel_key key; 71 #ifdef CONFIG_DST_CACHE 72 struct dst_cache dst_cache; 73 #endif 74 u8 options_len; 75 u8 mode; 76 }; 77 78 /* 6rd prefix/relay information */ 79 #ifdef CONFIG_IPV6_SIT_6RD 80 struct ip_tunnel_6rd_parm { 81 struct in6_addr prefix; 82 __be32 relay_prefix; 83 u16 prefixlen; 84 u16 relay_prefixlen; 85 }; 86 #endif 87 88 struct ip_tunnel_encap { 89 u16 type; 90 u16 flags; 91 __be16 sport; 92 __be16 dport; 93 }; 94 95 struct ip_tunnel_prl_entry { 96 struct ip_tunnel_prl_entry __rcu *next; 97 __be32 addr; 98 u16 flags; 99 struct rcu_head rcu_head; 100 }; 101 102 struct metadata_dst; 103 104 struct ip_tunnel { 105 struct ip_tunnel __rcu *next; 106 struct hlist_node hash_node; 107 struct net_device *dev; 108 struct net *net; /* netns for packet i/o */ 109 110 unsigned long err_time; /* Time when the last ICMP error 111 * arrived */ 112 int err_count; /* Number of arrived ICMP errors */ 113 114 /* These four fields used only by GRE */ 115 u32 i_seqno; /* The last seen seqno */ 116 u32 o_seqno; /* The last output seqno */ 117 int tun_hlen; /* Precalculated header length */ 118 119 /* These four fields used only by ERSPAN */ 120 u32 index; /* ERSPAN type II index */ 121 u8 erspan_ver; /* ERSPAN version */ 122 u8 dir; /* ERSPAN direction */ 123 u16 hwid; /* ERSPAN hardware ID */ 124 125 struct dst_cache dst_cache; 126 127 struct ip_tunnel_parm parms; 128 129 int mlink; 130 int encap_hlen; /* Encap header length (FOU,GUE) */ 131 int hlen; /* tun_hlen + encap_hlen */ 132 struct ip_tunnel_encap encap; 133 134 /* for SIT */ 135 #ifdef CONFIG_IPV6_SIT_6RD 136 struct ip_tunnel_6rd_parm ip6rd; 137 #endif 138 struct ip_tunnel_prl_entry __rcu *prl; /* potential router list */ 139 unsigned int prl_count; /* # of entries in PRL */ 140 unsigned int ip_tnl_net_id; 141 struct gro_cells gro_cells; 142 __u32 fwmark; 143 bool collect_md; 144 bool ignore_df; 145 }; 146 147 #define TUNNEL_CSUM __cpu_to_be16(0x01) 148 #define TUNNEL_ROUTING __cpu_to_be16(0x02) 149 #define TUNNEL_KEY __cpu_to_be16(0x04) 150 #define TUNNEL_SEQ __cpu_to_be16(0x08) 151 #define TUNNEL_STRICT __cpu_to_be16(0x10) 152 #define TUNNEL_REC __cpu_to_be16(0x20) 153 #define TUNNEL_VERSION __cpu_to_be16(0x40) 154 #define TUNNEL_NO_KEY __cpu_to_be16(0x80) 155 #define TUNNEL_DONT_FRAGMENT __cpu_to_be16(0x0100) 156 #define TUNNEL_OAM __cpu_to_be16(0x0200) 157 #define TUNNEL_CRIT_OPT __cpu_to_be16(0x0400) 158 #define TUNNEL_GENEVE_OPT __cpu_to_be16(0x0800) 159 #define TUNNEL_VXLAN_OPT __cpu_to_be16(0x1000) 160 #define TUNNEL_NOCACHE __cpu_to_be16(0x2000) 161 #define TUNNEL_ERSPAN_OPT __cpu_to_be16(0x4000) 162 163 #define TUNNEL_OPTIONS_PRESENT \ 164 (TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT | TUNNEL_ERSPAN_OPT) 165 166 struct tnl_ptk_info { 167 __be16 flags; 168 __be16 proto; 169 __be32 key; 170 __be32 seq; 171 int hdr_len; 172 }; 173 174 #define PACKET_RCVD 0 175 #define PACKET_REJECT 1 176 #define PACKET_NEXT 2 177 178 #define IP_TNL_HASH_BITS 7 179 #define IP_TNL_HASH_SIZE (1 << IP_TNL_HASH_BITS) 180 181 struct ip_tunnel_net { 182 struct net_device *fb_tunnel_dev; 183 struct hlist_head tunnels[IP_TNL_HASH_SIZE]; 184 struct ip_tunnel __rcu *collect_md_tun; 185 }; 186 187 static inline void ip_tunnel_key_init(struct ip_tunnel_key *key, 188 __be32 saddr, __be32 daddr, 189 u8 tos, u8 ttl, __be32 label, 190 __be16 tp_src, __be16 tp_dst, 191 __be64 tun_id, __be16 tun_flags) 192 { 193 key->tun_id = tun_id; 194 key->u.ipv4.src = saddr; 195 key->u.ipv4.dst = daddr; 196 memset((unsigned char *)key + IP_TUNNEL_KEY_IPV4_PAD, 197 0, IP_TUNNEL_KEY_IPV4_PAD_LEN); 198 key->tos = tos; 199 key->ttl = ttl; 200 key->label = label; 201 key->tun_flags = tun_flags; 202 203 /* For the tunnel types on the top of IPsec, the tp_src and tp_dst of 204 * the upper tunnel are used. 205 * E.g: GRE over IPSEC, the tp_src and tp_port are zero. 206 */ 207 key->tp_src = tp_src; 208 key->tp_dst = tp_dst; 209 210 /* Clear struct padding. */ 211 if (sizeof(*key) != IP_TUNNEL_KEY_SIZE) 212 memset((unsigned char *)key + IP_TUNNEL_KEY_SIZE, 213 0, sizeof(*key) - IP_TUNNEL_KEY_SIZE); 214 } 215 216 static inline bool 217 ip_tunnel_dst_cache_usable(const struct sk_buff *skb, 218 const struct ip_tunnel_info *info) 219 { 220 if (skb->mark) 221 return false; 222 if (!info) 223 return true; 224 if (info->key.tun_flags & TUNNEL_NOCACHE) 225 return false; 226 227 return true; 228 } 229 230 static inline unsigned short ip_tunnel_info_af(const struct ip_tunnel_info 231 *tun_info) 232 { 233 return tun_info->mode & IP_TUNNEL_INFO_IPV6 ? AF_INET6 : AF_INET; 234 } 235 236 static inline __be64 key32_to_tunnel_id(__be32 key) 237 { 238 #ifdef __BIG_ENDIAN 239 return (__force __be64)key; 240 #else 241 return (__force __be64)((__force u64)key << 32); 242 #endif 243 } 244 245 /* Returns the least-significant 32 bits of a __be64. */ 246 static inline __be32 tunnel_id_to_key32(__be64 tun_id) 247 { 248 #ifdef __BIG_ENDIAN 249 return (__force __be32)tun_id; 250 #else 251 return (__force __be32)((__force u64)tun_id >> 32); 252 #endif 253 } 254 255 #ifdef CONFIG_INET 256 257 int ip_tunnel_init(struct net_device *dev); 258 void ip_tunnel_uninit(struct net_device *dev); 259 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head); 260 struct net *ip_tunnel_get_link_net(const struct net_device *dev); 261 int ip_tunnel_get_iflink(const struct net_device *dev); 262 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id, 263 struct rtnl_link_ops *ops, char *devname); 264 265 void ip_tunnel_delete_nets(struct list_head *list_net, unsigned int id, 266 struct rtnl_link_ops *ops); 267 268 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 269 const struct iphdr *tnl_params, const u8 protocol); 270 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 271 const u8 proto); 272 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd); 273 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict); 274 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu); 275 276 void ip_tunnel_get_stats64(struct net_device *dev, 277 struct rtnl_link_stats64 *tot); 278 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn, 279 int link, __be16 flags, 280 __be32 remote, __be32 local, 281 __be32 key); 282 283 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb, 284 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst, 285 bool log_ecn_error); 286 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[], 287 struct ip_tunnel_parm *p, __u32 fwmark); 288 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], 289 struct ip_tunnel_parm *p, __u32 fwmark); 290 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id); 291 292 struct ip_tunnel_encap_ops { 293 size_t (*encap_hlen)(struct ip_tunnel_encap *e); 294 int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e, 295 u8 *protocol, struct flowi4 *fl4); 296 }; 297 298 #define MAX_IPTUN_ENCAP_OPS 8 299 300 extern const struct ip_tunnel_encap_ops __rcu * 301 iptun_encaps[MAX_IPTUN_ENCAP_OPS]; 302 303 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op, 304 unsigned int num); 305 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op, 306 unsigned int num); 307 308 int ip_tunnel_encap_setup(struct ip_tunnel *t, 309 struct ip_tunnel_encap *ipencap); 310 311 static inline int ip_encap_hlen(struct ip_tunnel_encap *e) 312 { 313 const struct ip_tunnel_encap_ops *ops; 314 int hlen = -EINVAL; 315 316 if (e->type == TUNNEL_ENCAP_NONE) 317 return 0; 318 319 if (e->type >= MAX_IPTUN_ENCAP_OPS) 320 return -EINVAL; 321 322 rcu_read_lock(); 323 ops = rcu_dereference(iptun_encaps[e->type]); 324 if (likely(ops && ops->encap_hlen)) 325 hlen = ops->encap_hlen(e); 326 rcu_read_unlock(); 327 328 return hlen; 329 } 330 331 static inline int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t, 332 u8 *protocol, struct flowi4 *fl4) 333 { 334 const struct ip_tunnel_encap_ops *ops; 335 int ret = -EINVAL; 336 337 if (t->encap.type == TUNNEL_ENCAP_NONE) 338 return 0; 339 340 if (t->encap.type >= MAX_IPTUN_ENCAP_OPS) 341 return -EINVAL; 342 343 rcu_read_lock(); 344 ops = rcu_dereference(iptun_encaps[t->encap.type]); 345 if (likely(ops && ops->build_header)) 346 ret = ops->build_header(skb, &t->encap, protocol, fl4); 347 rcu_read_unlock(); 348 349 return ret; 350 } 351 352 /* Extract dsfield from inner protocol */ 353 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph, 354 const struct sk_buff *skb) 355 { 356 if (skb->protocol == htons(ETH_P_IP)) 357 return iph->tos; 358 else if (skb->protocol == htons(ETH_P_IPV6)) 359 return ipv6_get_dsfield((const struct ipv6hdr *)iph); 360 else 361 return 0; 362 } 363 364 /* Propogate ECN bits out */ 365 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph, 366 const struct sk_buff *skb) 367 { 368 u8 inner = ip_tunnel_get_dsfield(iph, skb); 369 370 return INET_ECN_encapsulate(tos, inner); 371 } 372 373 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len, 374 __be16 inner_proto, bool raw_proto, bool xnet); 375 376 static inline int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, 377 __be16 inner_proto, bool xnet) 378 { 379 return __iptunnel_pull_header(skb, hdr_len, inner_proto, false, xnet); 380 } 381 382 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, 383 __be32 src, __be32 dst, u8 proto, 384 u8 tos, u8 ttl, __be16 df, bool xnet); 385 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md, 386 gfp_t flags); 387 388 int iptunnel_handle_offloads(struct sk_buff *skb, int gso_type_mask); 389 390 static inline int iptunnel_pull_offloads(struct sk_buff *skb) 391 { 392 if (skb_is_gso(skb)) { 393 int err; 394 395 err = skb_unclone(skb, GFP_ATOMIC); 396 if (unlikely(err)) 397 return err; 398 skb_shinfo(skb)->gso_type &= ~(NETIF_F_GSO_ENCAP_ALL >> 399 NETIF_F_GSO_SHIFT); 400 } 401 402 skb->encapsulation = 0; 403 return 0; 404 } 405 406 static inline void iptunnel_xmit_stats(struct net_device *dev, int pkt_len) 407 { 408 if (pkt_len > 0) { 409 struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats); 410 411 u64_stats_update_begin(&tstats->syncp); 412 tstats->tx_bytes += pkt_len; 413 tstats->tx_packets++; 414 u64_stats_update_end(&tstats->syncp); 415 put_cpu_ptr(tstats); 416 } else { 417 struct net_device_stats *err_stats = &dev->stats; 418 419 if (pkt_len < 0) { 420 err_stats->tx_errors++; 421 err_stats->tx_aborted_errors++; 422 } else { 423 err_stats->tx_dropped++; 424 } 425 } 426 } 427 428 static inline void *ip_tunnel_info_opts(struct ip_tunnel_info *info) 429 { 430 return info + 1; 431 } 432 433 static inline void ip_tunnel_info_opts_get(void *to, 434 const struct ip_tunnel_info *info) 435 { 436 memcpy(to, info + 1, info->options_len); 437 } 438 439 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info, 440 const void *from, int len) 441 { 442 memcpy(ip_tunnel_info_opts(info), from, len); 443 info->options_len = len; 444 } 445 446 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate) 447 { 448 return (struct ip_tunnel_info *)lwtstate->data; 449 } 450 451 extern struct static_key ip_tunnel_metadata_cnt; 452 453 /* Returns > 0 if metadata should be collected */ 454 static inline int ip_tunnel_collect_metadata(void) 455 { 456 return static_key_false(&ip_tunnel_metadata_cnt); 457 } 458 459 void __init ip_tunnel_core_init(void); 460 461 void ip_tunnel_need_metadata(void); 462 void ip_tunnel_unneed_metadata(void); 463 464 #else /* CONFIG_INET */ 465 466 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate) 467 { 468 return NULL; 469 } 470 471 static inline void ip_tunnel_need_metadata(void) 472 { 473 } 474 475 static inline void ip_tunnel_unneed_metadata(void) 476 { 477 } 478 479 static inline void ip_tunnel_info_opts_get(void *to, 480 const struct ip_tunnel_info *info) 481 { 482 } 483 484 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info, 485 const void *from, int len) 486 { 487 info->options_len = 0; 488 } 489 490 #endif /* CONFIG_INET */ 491 492 #endif /* __NET_IP_TUNNELS_H */ 493