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