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