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 /* This field used only by ERSPAN */ 120 u32 index; /* ERSPAN type II index */ 121 122 struct dst_cache dst_cache; 123 124 struct ip_tunnel_parm parms; 125 126 int mlink; 127 int encap_hlen; /* Encap header length (FOU,GUE) */ 128 int hlen; /* tun_hlen + encap_hlen */ 129 struct ip_tunnel_encap encap; 130 131 /* for SIT */ 132 #ifdef CONFIG_IPV6_SIT_6RD 133 struct ip_tunnel_6rd_parm ip6rd; 134 #endif 135 struct ip_tunnel_prl_entry __rcu *prl; /* potential router list */ 136 unsigned int prl_count; /* # of entries in PRL */ 137 unsigned int ip_tnl_net_id; 138 struct gro_cells gro_cells; 139 __u32 fwmark; 140 bool collect_md; 141 bool ignore_df; 142 }; 143 144 #define TUNNEL_CSUM __cpu_to_be16(0x01) 145 #define TUNNEL_ROUTING __cpu_to_be16(0x02) 146 #define TUNNEL_KEY __cpu_to_be16(0x04) 147 #define TUNNEL_SEQ __cpu_to_be16(0x08) 148 #define TUNNEL_STRICT __cpu_to_be16(0x10) 149 #define TUNNEL_REC __cpu_to_be16(0x20) 150 #define TUNNEL_VERSION __cpu_to_be16(0x40) 151 #define TUNNEL_NO_KEY __cpu_to_be16(0x80) 152 #define TUNNEL_DONT_FRAGMENT __cpu_to_be16(0x0100) 153 #define TUNNEL_OAM __cpu_to_be16(0x0200) 154 #define TUNNEL_CRIT_OPT __cpu_to_be16(0x0400) 155 #define TUNNEL_GENEVE_OPT __cpu_to_be16(0x0800) 156 #define TUNNEL_VXLAN_OPT __cpu_to_be16(0x1000) 157 #define TUNNEL_NOCACHE __cpu_to_be16(0x2000) 158 #define TUNNEL_ERSPAN_OPT __cpu_to_be16(0x4000) 159 160 #define TUNNEL_OPTIONS_PRESENT \ 161 (TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT | TUNNEL_ERSPAN_OPT) 162 163 struct tnl_ptk_info { 164 __be16 flags; 165 __be16 proto; 166 __be32 key; 167 __be32 seq; 168 int hdr_len; 169 }; 170 171 #define PACKET_RCVD 0 172 #define PACKET_REJECT 1 173 #define PACKET_NEXT 2 174 175 #define IP_TNL_HASH_BITS 7 176 #define IP_TNL_HASH_SIZE (1 << IP_TNL_HASH_BITS) 177 178 struct ip_tunnel_net { 179 struct net_device *fb_tunnel_dev; 180 struct hlist_head tunnels[IP_TNL_HASH_SIZE]; 181 struct ip_tunnel __rcu *collect_md_tun; 182 }; 183 184 static inline void ip_tunnel_key_init(struct ip_tunnel_key *key, 185 __be32 saddr, __be32 daddr, 186 u8 tos, u8 ttl, __be32 label, 187 __be16 tp_src, __be16 tp_dst, 188 __be64 tun_id, __be16 tun_flags) 189 { 190 key->tun_id = tun_id; 191 key->u.ipv4.src = saddr; 192 key->u.ipv4.dst = daddr; 193 memset((unsigned char *)key + IP_TUNNEL_KEY_IPV4_PAD, 194 0, IP_TUNNEL_KEY_IPV4_PAD_LEN); 195 key->tos = tos; 196 key->ttl = ttl; 197 key->label = label; 198 key->tun_flags = tun_flags; 199 200 /* For the tunnel types on the top of IPsec, the tp_src and tp_dst of 201 * the upper tunnel are used. 202 * E.g: GRE over IPSEC, the tp_src and tp_port are zero. 203 */ 204 key->tp_src = tp_src; 205 key->tp_dst = tp_dst; 206 207 /* Clear struct padding. */ 208 if (sizeof(*key) != IP_TUNNEL_KEY_SIZE) 209 memset((unsigned char *)key + IP_TUNNEL_KEY_SIZE, 210 0, sizeof(*key) - IP_TUNNEL_KEY_SIZE); 211 } 212 213 static inline bool 214 ip_tunnel_dst_cache_usable(const struct sk_buff *skb, 215 const struct ip_tunnel_info *info) 216 { 217 if (skb->mark) 218 return false; 219 if (!info) 220 return true; 221 if (info->key.tun_flags & TUNNEL_NOCACHE) 222 return false; 223 224 return true; 225 } 226 227 static inline unsigned short ip_tunnel_info_af(const struct ip_tunnel_info 228 *tun_info) 229 { 230 return tun_info->mode & IP_TUNNEL_INFO_IPV6 ? AF_INET6 : AF_INET; 231 } 232 233 static inline __be64 key32_to_tunnel_id(__be32 key) 234 { 235 #ifdef __BIG_ENDIAN 236 return (__force __be64)key; 237 #else 238 return (__force __be64)((__force u64)key << 32); 239 #endif 240 } 241 242 /* Returns the least-significant 32 bits of a __be64. */ 243 static inline __be32 tunnel_id_to_key32(__be64 tun_id) 244 { 245 #ifdef __BIG_ENDIAN 246 return (__force __be32)tun_id; 247 #else 248 return (__force __be32)((__force u64)tun_id >> 32); 249 #endif 250 } 251 252 #ifdef CONFIG_INET 253 254 int ip_tunnel_init(struct net_device *dev); 255 void ip_tunnel_uninit(struct net_device *dev); 256 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head); 257 struct net *ip_tunnel_get_link_net(const struct net_device *dev); 258 int ip_tunnel_get_iflink(const struct net_device *dev); 259 int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id, 260 struct rtnl_link_ops *ops, char *devname); 261 262 void ip_tunnel_delete_nets(struct list_head *list_net, unsigned int id, 263 struct rtnl_link_ops *ops); 264 265 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 266 const struct iphdr *tnl_params, const u8 protocol); 267 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, 268 const u8 proto); 269 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd); 270 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict); 271 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu); 272 273 void ip_tunnel_get_stats64(struct net_device *dev, 274 struct rtnl_link_stats64 *tot); 275 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn, 276 int link, __be16 flags, 277 __be32 remote, __be32 local, 278 __be32 key); 279 280 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb, 281 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst, 282 bool log_ecn_error); 283 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[], 284 struct ip_tunnel_parm *p, __u32 fwmark); 285 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], 286 struct ip_tunnel_parm *p, __u32 fwmark); 287 void ip_tunnel_setup(struct net_device *dev, unsigned int net_id); 288 289 struct ip_tunnel_encap_ops { 290 size_t (*encap_hlen)(struct ip_tunnel_encap *e); 291 int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e, 292 u8 *protocol, struct flowi4 *fl4); 293 }; 294 295 #define MAX_IPTUN_ENCAP_OPS 8 296 297 extern const struct ip_tunnel_encap_ops __rcu * 298 iptun_encaps[MAX_IPTUN_ENCAP_OPS]; 299 300 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op, 301 unsigned int num); 302 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op, 303 unsigned int num); 304 305 int ip_tunnel_encap_setup(struct ip_tunnel *t, 306 struct ip_tunnel_encap *ipencap); 307 308 static inline int ip_encap_hlen(struct ip_tunnel_encap *e) 309 { 310 const struct ip_tunnel_encap_ops *ops; 311 int hlen = -EINVAL; 312 313 if (e->type == TUNNEL_ENCAP_NONE) 314 return 0; 315 316 if (e->type >= MAX_IPTUN_ENCAP_OPS) 317 return -EINVAL; 318 319 rcu_read_lock(); 320 ops = rcu_dereference(iptun_encaps[e->type]); 321 if (likely(ops && ops->encap_hlen)) 322 hlen = ops->encap_hlen(e); 323 rcu_read_unlock(); 324 325 return hlen; 326 } 327 328 static inline int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t, 329 u8 *protocol, struct flowi4 *fl4) 330 { 331 const struct ip_tunnel_encap_ops *ops; 332 int ret = -EINVAL; 333 334 if (t->encap.type == TUNNEL_ENCAP_NONE) 335 return 0; 336 337 if (t->encap.type >= MAX_IPTUN_ENCAP_OPS) 338 return -EINVAL; 339 340 rcu_read_lock(); 341 ops = rcu_dereference(iptun_encaps[t->encap.type]); 342 if (likely(ops && ops->build_header)) 343 ret = ops->build_header(skb, &t->encap, protocol, fl4); 344 rcu_read_unlock(); 345 346 return ret; 347 } 348 349 /* Extract dsfield from inner protocol */ 350 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph, 351 const struct sk_buff *skb) 352 { 353 if (skb->protocol == htons(ETH_P_IP)) 354 return iph->tos; 355 else if (skb->protocol == htons(ETH_P_IPV6)) 356 return ipv6_get_dsfield((const struct ipv6hdr *)iph); 357 else 358 return 0; 359 } 360 361 /* Propogate ECN bits out */ 362 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph, 363 const struct sk_buff *skb) 364 { 365 u8 inner = ip_tunnel_get_dsfield(iph, skb); 366 367 return INET_ECN_encapsulate(tos, inner); 368 } 369 370 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len, 371 __be16 inner_proto, bool raw_proto, bool xnet); 372 373 static inline int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, 374 __be16 inner_proto, bool xnet) 375 { 376 return __iptunnel_pull_header(skb, hdr_len, inner_proto, false, xnet); 377 } 378 379 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, 380 __be32 src, __be32 dst, u8 proto, 381 u8 tos, u8 ttl, __be16 df, bool xnet); 382 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md, 383 gfp_t flags); 384 385 int iptunnel_handle_offloads(struct sk_buff *skb, int gso_type_mask); 386 387 static inline int iptunnel_pull_offloads(struct sk_buff *skb) 388 { 389 if (skb_is_gso(skb)) { 390 int err; 391 392 err = skb_unclone(skb, GFP_ATOMIC); 393 if (unlikely(err)) 394 return err; 395 skb_shinfo(skb)->gso_type &= ~(NETIF_F_GSO_ENCAP_ALL >> 396 NETIF_F_GSO_SHIFT); 397 } 398 399 skb->encapsulation = 0; 400 return 0; 401 } 402 403 static inline void iptunnel_xmit_stats(struct net_device *dev, int pkt_len) 404 { 405 if (pkt_len > 0) { 406 struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats); 407 408 u64_stats_update_begin(&tstats->syncp); 409 tstats->tx_bytes += pkt_len; 410 tstats->tx_packets++; 411 u64_stats_update_end(&tstats->syncp); 412 put_cpu_ptr(tstats); 413 } else { 414 struct net_device_stats *err_stats = &dev->stats; 415 416 if (pkt_len < 0) { 417 err_stats->tx_errors++; 418 err_stats->tx_aborted_errors++; 419 } else { 420 err_stats->tx_dropped++; 421 } 422 } 423 } 424 425 static inline void *ip_tunnel_info_opts(struct ip_tunnel_info *info) 426 { 427 return info + 1; 428 } 429 430 static inline void ip_tunnel_info_opts_get(void *to, 431 const struct ip_tunnel_info *info) 432 { 433 memcpy(to, info + 1, info->options_len); 434 } 435 436 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info, 437 const void *from, int len) 438 { 439 memcpy(ip_tunnel_info_opts(info), from, len); 440 info->options_len = len; 441 } 442 443 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate) 444 { 445 return (struct ip_tunnel_info *)lwtstate->data; 446 } 447 448 extern struct static_key ip_tunnel_metadata_cnt; 449 450 /* Returns > 0 if metadata should be collected */ 451 static inline int ip_tunnel_collect_metadata(void) 452 { 453 return static_key_false(&ip_tunnel_metadata_cnt); 454 } 455 456 void __init ip_tunnel_core_init(void); 457 458 void ip_tunnel_need_metadata(void); 459 void ip_tunnel_unneed_metadata(void); 460 461 #else /* CONFIG_INET */ 462 463 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate) 464 { 465 return NULL; 466 } 467 468 static inline void ip_tunnel_need_metadata(void) 469 { 470 } 471 472 static inline void ip_tunnel_unneed_metadata(void) 473 { 474 } 475 476 static inline void ip_tunnel_info_opts_get(void *to, 477 const struct ip_tunnel_info *info) 478 { 479 } 480 481 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info, 482 const void *from, int len) 483 { 484 info->options_len = 0; 485 } 486 487 #endif /* CONFIG_INET */ 488 489 #endif /* __NET_IP_TUNNELS_H */ 490