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