1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __NET_VXLAN_H 3 #define __NET_VXLAN_H 1 4 5 #include <linux/if_vlan.h> 6 #include <net/udp_tunnel.h> 7 #include <net/dst_metadata.h> 8 9 /* VXLAN protocol (RFC 7348) header: 10 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 11 * |R|R|R|R|I|R|R|R| Reserved | 12 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 13 * | VXLAN Network Identifier (VNI) | Reserved | 14 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 15 * 16 * I = VXLAN Network Identifier (VNI) present. 17 */ 18 struct vxlanhdr { 19 __be32 vx_flags; 20 __be32 vx_vni; 21 }; 22 23 /* VXLAN header flags. */ 24 #define VXLAN_HF_VNI cpu_to_be32(BIT(27)) 25 26 #define VXLAN_N_VID (1u << 24) 27 #define VXLAN_VID_MASK (VXLAN_N_VID - 1) 28 #define VXLAN_VNI_MASK cpu_to_be32(VXLAN_VID_MASK << 8) 29 #define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr)) 30 31 #define VNI_HASH_BITS 10 32 #define VNI_HASH_SIZE (1<<VNI_HASH_BITS) 33 #define FDB_HASH_BITS 8 34 #define FDB_HASH_SIZE (1<<FDB_HASH_BITS) 35 36 /* Remote checksum offload for VXLAN (VXLAN_F_REMCSUM_[RT]X): 37 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 38 * |R|R|R|R|I|R|R|R|R|R|C| Reserved | 39 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 40 * | VXLAN Network Identifier (VNI) |O| Csum start | 41 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 42 * 43 * C = Remote checksum offload bit. When set indicates that the 44 * remote checksum offload data is present. 45 * 46 * O = Offset bit. Indicates the checksum offset relative to 47 * checksum start. 48 * 49 * Csum start = Checksum start divided by two. 50 * 51 * http://tools.ietf.org/html/draft-herbert-vxlan-rco 52 */ 53 54 /* VXLAN-RCO header flags. */ 55 #define VXLAN_HF_RCO cpu_to_be32(BIT(21)) 56 57 /* Remote checksum offload header option */ 58 #define VXLAN_RCO_MASK cpu_to_be32(0x7f) /* Last byte of vni field */ 59 #define VXLAN_RCO_UDP cpu_to_be32(0x80) /* Indicate UDP RCO (TCP when not set *) */ 60 #define VXLAN_RCO_SHIFT 1 /* Left shift of start */ 61 #define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1) 62 #define VXLAN_MAX_REMCSUM_START (0x7f << VXLAN_RCO_SHIFT) 63 64 /* 65 * VXLAN Group Based Policy Extension (VXLAN_F_GBP): 66 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 67 * |G|R|R|R|I|R|R|R|R|D|R|R|A|R|R|R| Group Policy ID | 68 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 69 * | VXLAN Network Identifier (VNI) | Reserved | 70 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 71 * 72 * G = Group Policy ID present. 73 * 74 * D = Don't Learn bit. When set, this bit indicates that the egress 75 * VTEP MUST NOT learn the source address of the encapsulated frame. 76 * 77 * A = Indicates that the group policy has already been applied to 78 * this packet. Policies MUST NOT be applied by devices when the 79 * A bit is set. 80 * 81 * https://tools.ietf.org/html/draft-smith-vxlan-group-policy 82 */ 83 struct vxlanhdr_gbp { 84 u8 vx_flags; 85 #ifdef __LITTLE_ENDIAN_BITFIELD 86 u8 reserved_flags1:3, 87 policy_applied:1, 88 reserved_flags2:2, 89 dont_learn:1, 90 reserved_flags3:1; 91 #elif defined(__BIG_ENDIAN_BITFIELD) 92 u8 reserved_flags1:1, 93 dont_learn:1, 94 reserved_flags2:2, 95 policy_applied:1, 96 reserved_flags3:3; 97 #else 98 #error "Please fix <asm/byteorder.h>" 99 #endif 100 __be16 policy_id; 101 __be32 vx_vni; 102 }; 103 104 /* VXLAN-GBP header flags. */ 105 #define VXLAN_HF_GBP cpu_to_be32(BIT(31)) 106 107 #define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | cpu_to_be32(0xFFFFFF)) 108 109 /* skb->mark mapping 110 * 111 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 112 * |R|R|R|R|R|R|R|R|R|D|R|R|A|R|R|R| Group Policy ID | 113 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 114 */ 115 #define VXLAN_GBP_DONT_LEARN (BIT(6) << 16) 116 #define VXLAN_GBP_POLICY_APPLIED (BIT(3) << 16) 117 #define VXLAN_GBP_ID_MASK (0xFFFF) 118 119 /* 120 * VXLAN Generic Protocol Extension (VXLAN_F_GPE): 121 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 122 * |R|R|Ver|I|P|R|O| Reserved |Next Protocol | 123 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 124 * | VXLAN Network Identifier (VNI) | Reserved | 125 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 126 * 127 * Ver = Version. Indicates VXLAN GPE protocol version. 128 * 129 * P = Next Protocol Bit. The P bit is set to indicate that the 130 * Next Protocol field is present. 131 * 132 * O = OAM Flag Bit. The O bit is set to indicate that the packet 133 * is an OAM packet. 134 * 135 * Next Protocol = This 8 bit field indicates the protocol header 136 * immediately following the VXLAN GPE header. 137 * 138 * https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-01 139 */ 140 141 struct vxlanhdr_gpe { 142 #if defined(__LITTLE_ENDIAN_BITFIELD) 143 u8 oam_flag:1, 144 reserved_flags1:1, 145 np_applied:1, 146 instance_applied:1, 147 version:2, 148 reserved_flags2:2; 149 #elif defined(__BIG_ENDIAN_BITFIELD) 150 u8 reserved_flags2:2, 151 version:2, 152 instance_applied:1, 153 np_applied:1, 154 reserved_flags1:1, 155 oam_flag:1; 156 #endif 157 u8 reserved_flags3; 158 u8 reserved_flags4; 159 u8 next_protocol; 160 __be32 vx_vni; 161 }; 162 163 /* VXLAN-GPE header flags. */ 164 #define VXLAN_HF_VER cpu_to_be32(BIT(29) | BIT(28)) 165 #define VXLAN_HF_NP cpu_to_be32(BIT(26)) 166 #define VXLAN_HF_OAM cpu_to_be32(BIT(24)) 167 168 #define VXLAN_GPE_USED_BITS (VXLAN_HF_VER | VXLAN_HF_NP | VXLAN_HF_OAM | \ 169 cpu_to_be32(0xff)) 170 171 struct vxlan_metadata { 172 u32 gbp; 173 }; 174 175 /* per UDP socket information */ 176 struct vxlan_sock { 177 struct hlist_node hlist; 178 struct socket *sock; 179 struct hlist_head vni_list[VNI_HASH_SIZE]; 180 refcount_t refcnt; 181 u32 flags; 182 }; 183 184 union vxlan_addr { 185 struct sockaddr_in sin; 186 struct sockaddr_in6 sin6; 187 struct sockaddr sa; 188 }; 189 190 struct vxlan_rdst { 191 union vxlan_addr remote_ip; 192 __be16 remote_port; 193 __be32 remote_vni; 194 u32 remote_ifindex; 195 struct list_head list; 196 struct rcu_head rcu; 197 struct dst_cache dst_cache; 198 }; 199 200 struct vxlan_config { 201 union vxlan_addr remote_ip; 202 union vxlan_addr saddr; 203 __be32 vni; 204 int remote_ifindex; 205 int mtu; 206 __be16 dst_port; 207 u16 port_min; 208 u16 port_max; 209 u8 tos; 210 u8 ttl; 211 __be32 label; 212 u32 flags; 213 unsigned long age_interval; 214 unsigned int addrmax; 215 bool no_share; 216 }; 217 218 struct vxlan_dev_node { 219 struct hlist_node hlist; 220 struct vxlan_dev *vxlan; 221 }; 222 223 /* Pseudo network device */ 224 struct vxlan_dev { 225 struct vxlan_dev_node hlist4; /* vni hash table for IPv4 socket */ 226 #if IS_ENABLED(CONFIG_IPV6) 227 struct vxlan_dev_node hlist6; /* vni hash table for IPv6 socket */ 228 #endif 229 struct list_head next; /* vxlan's per namespace list */ 230 struct vxlan_sock __rcu *vn4_sock; /* listening socket for IPv4 */ 231 #if IS_ENABLED(CONFIG_IPV6) 232 struct vxlan_sock __rcu *vn6_sock; /* listening socket for IPv6 */ 233 #endif 234 struct net_device *dev; 235 struct net *net; /* netns for packet i/o */ 236 struct vxlan_rdst default_dst; /* default destination */ 237 238 struct timer_list age_timer; 239 spinlock_t hash_lock; 240 unsigned int addrcnt; 241 struct gro_cells gro_cells; 242 243 struct vxlan_config cfg; 244 245 struct hlist_head fdb_head[FDB_HASH_SIZE]; 246 }; 247 248 #define VXLAN_F_LEARN 0x01 249 #define VXLAN_F_PROXY 0x02 250 #define VXLAN_F_RSC 0x04 251 #define VXLAN_F_L2MISS 0x08 252 #define VXLAN_F_L3MISS 0x10 253 #define VXLAN_F_IPV6 0x20 254 #define VXLAN_F_UDP_ZERO_CSUM_TX 0x40 255 #define VXLAN_F_UDP_ZERO_CSUM6_TX 0x80 256 #define VXLAN_F_UDP_ZERO_CSUM6_RX 0x100 257 #define VXLAN_F_REMCSUM_TX 0x200 258 #define VXLAN_F_REMCSUM_RX 0x400 259 #define VXLAN_F_GBP 0x800 260 #define VXLAN_F_REMCSUM_NOPARTIAL 0x1000 261 #define VXLAN_F_COLLECT_METADATA 0x2000 262 #define VXLAN_F_GPE 0x4000 263 #define VXLAN_F_IPV6_LINKLOCAL 0x8000 264 #define VXLAN_F_TTL_INHERIT 0x10000 265 266 /* Flags that are used in the receive path. These flags must match in 267 * order for a socket to be shareable 268 */ 269 #define VXLAN_F_RCV_FLAGS (VXLAN_F_GBP | \ 270 VXLAN_F_GPE | \ 271 VXLAN_F_UDP_ZERO_CSUM6_RX | \ 272 VXLAN_F_REMCSUM_RX | \ 273 VXLAN_F_REMCSUM_NOPARTIAL | \ 274 VXLAN_F_COLLECT_METADATA) 275 276 /* Flags that can be set together with VXLAN_F_GPE. */ 277 #define VXLAN_F_ALLOWED_GPE (VXLAN_F_GPE | \ 278 VXLAN_F_IPV6 | \ 279 VXLAN_F_IPV6_LINKLOCAL | \ 280 VXLAN_F_UDP_ZERO_CSUM_TX | \ 281 VXLAN_F_UDP_ZERO_CSUM6_TX | \ 282 VXLAN_F_UDP_ZERO_CSUM6_RX | \ 283 VXLAN_F_COLLECT_METADATA) 284 285 struct net_device *vxlan_dev_create(struct net *net, const char *name, 286 u8 name_assign_type, struct vxlan_config *conf); 287 288 static inline netdev_features_t vxlan_features_check(struct sk_buff *skb, 289 netdev_features_t features) 290 { 291 u8 l4_hdr = 0; 292 293 if (!skb->encapsulation) 294 return features; 295 296 switch (vlan_get_protocol(skb)) { 297 case htons(ETH_P_IP): 298 l4_hdr = ip_hdr(skb)->protocol; 299 break; 300 case htons(ETH_P_IPV6): 301 l4_hdr = ipv6_hdr(skb)->nexthdr; 302 break; 303 default: 304 return features; 305 } 306 307 if ((l4_hdr == IPPROTO_UDP) && 308 (skb->inner_protocol_type != ENCAP_TYPE_ETHER || 309 skb->inner_protocol != htons(ETH_P_TEB) || 310 (skb_inner_mac_header(skb) - skb_transport_header(skb) != 311 sizeof(struct udphdr) + sizeof(struct vxlanhdr)) || 312 (skb->ip_summed != CHECKSUM_NONE && 313 !can_checksum_protocol(features, inner_eth_hdr(skb)->h_proto)))) 314 return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); 315 316 return features; 317 } 318 319 /* IP header + UDP + VXLAN + Ethernet header */ 320 #define VXLAN_HEADROOM (20 + 8 + 8 + 14) 321 /* IPv6 header + UDP + VXLAN + Ethernet header */ 322 #define VXLAN6_HEADROOM (40 + 8 + 8 + 14) 323 324 static inline struct vxlanhdr *vxlan_hdr(struct sk_buff *skb) 325 { 326 return (struct vxlanhdr *)(udp_hdr(skb) + 1); 327 } 328 329 static inline __be32 vxlan_vni(__be32 vni_field) 330 { 331 #if defined(__BIG_ENDIAN) 332 return (__force __be32)((__force u32)vni_field >> 8); 333 #else 334 return (__force __be32)((__force u32)(vni_field & VXLAN_VNI_MASK) << 8); 335 #endif 336 } 337 338 static inline __be32 vxlan_vni_field(__be32 vni) 339 { 340 #if defined(__BIG_ENDIAN) 341 return (__force __be32)((__force u32)vni << 8); 342 #else 343 return (__force __be32)((__force u32)vni >> 8); 344 #endif 345 } 346 347 static inline size_t vxlan_rco_start(__be32 vni_field) 348 { 349 return be32_to_cpu(vni_field & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT; 350 } 351 352 static inline size_t vxlan_rco_offset(__be32 vni_field) 353 { 354 return (vni_field & VXLAN_RCO_UDP) ? 355 offsetof(struct udphdr, check) : 356 offsetof(struct tcphdr, check); 357 } 358 359 static inline __be32 vxlan_compute_rco(unsigned int start, unsigned int offset) 360 { 361 __be32 vni_field = cpu_to_be32(start >> VXLAN_RCO_SHIFT); 362 363 if (offset == offsetof(struct udphdr, check)) 364 vni_field |= VXLAN_RCO_UDP; 365 return vni_field; 366 } 367 368 static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs) 369 { 370 return vs->sock->sk->sk_family; 371 } 372 373 #endif 374