LXR linux/include/net/vxlan.h

   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#include <net/rtnetlink.h>
   9#include <net/switchdev.h>
  10
  11#define IANA_VXLAN_UDP_PORT     4789
  12
  13/* VXLAN protocol (RFC 7348) header:
  14 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  15 * |R|R|R|R|I|R|R|R|               Reserved                        |
  16 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  17 * |                VXLAN Network Identifier (VNI) |   Reserved    |
  18 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  19 *
  20 * I = VXLAN Network Identifier (VNI) present.
  21 */
  22struct vxlanhdr {
  23        __be32 vx_flags;
  24        __be32 vx_vni;
  25};
  26
  27/* VXLAN header flags. */
  28#define VXLAN_HF_VNI    cpu_to_be32(BIT(27))
  29
  30#define VXLAN_N_VID     (1u << 24)
  31#define VXLAN_VID_MASK  (VXLAN_N_VID - 1)
  32#define VXLAN_VNI_MASK  cpu_to_be32(VXLAN_VID_MASK << 8)
  33#define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
  34
  35#define VNI_HASH_BITS   10
  36#define VNI_HASH_SIZE   (1<<VNI_HASH_BITS)
  37#define FDB_HASH_BITS   8
  38#define FDB_HASH_SIZE   (1<<FDB_HASH_BITS)
  39
  40/* Remote checksum offload for VXLAN (VXLAN_F_REMCSUM_[RT]X):
  41 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  42 * |R|R|R|R|I|R|R|R|R|R|C|              Reserved                   |
  43 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  44 * |           VXLAN Network Identifier (VNI)      |O| Csum start  |
  45 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  46 *
  47 * C = Remote checksum offload bit. When set indicates that the
  48 *     remote checksum offload data is present.
  49 *
  50 * O = Offset bit. Indicates the checksum offset relative to
  51 *     checksum start.
  52 *
  53 * Csum start = Checksum start divided by two.
  54 *
  55 * http://tools.ietf.org/html/draft-herbert-vxlan-rco
  56 */
  57
  58/* VXLAN-RCO header flags. */
  59#define VXLAN_HF_RCO    cpu_to_be32(BIT(21))
  60
  61/* Remote checksum offload header option */
  62#define VXLAN_RCO_MASK  cpu_to_be32(0x7f)  /* Last byte of vni field */
  63#define VXLAN_RCO_UDP   cpu_to_be32(0x80)  /* Indicate UDP RCO (TCP when not set *) */
  64#define VXLAN_RCO_SHIFT 1                  /* Left shift of start */
  65#define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1)
  66#define VXLAN_MAX_REMCSUM_START (0x7f << VXLAN_RCO_SHIFT)
  67
  68/*
  69 * VXLAN Group Based Policy Extension (VXLAN_F_GBP):
  70 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  71 * |G|R|R|R|I|R|R|R|R|D|R|R|A|R|R|R|        Group Policy ID        |
  72 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  73 * |                VXLAN Network Identifier (VNI) |   Reserved    |
  74 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  75 *
  76 * G = Group Policy ID present.
  77 *
  78 * D = Don't Learn bit. When set, this bit indicates that the egress
  79 *     VTEP MUST NOT learn the source address of the encapsulated frame.
  80 *
  81 * A = Indicates that the group policy has already been applied to
  82 *     this packet. Policies MUST NOT be applied by devices when the
  83 *     A bit is set.
  84 *
  85 * https://tools.ietf.org/html/draft-smith-vxlan-group-policy
  86 */
  87struct vxlanhdr_gbp {
  88        u8      vx_flags;
  89#ifdef __LITTLE_ENDIAN_BITFIELD
  90        u8      reserved_flags1:3,
  91                policy_applied:1,
  92                reserved_flags2:2,
  93                dont_learn:1,
  94                reserved_flags3:1;
  95#elif defined(__BIG_ENDIAN_BITFIELD)
  96        u8      reserved_flags1:1,
  97                dont_learn:1,
  98                reserved_flags2:2,
  99                policy_applied:1,
 100                reserved_flags3:3;
 101#else
 102#error  "Please fix <asm/byteorder.h>"
 103#endif
 104        __be16  policy_id;
 105        __be32  vx_vni;
 106};
 107
 108/* VXLAN-GBP header flags. */
 109#define VXLAN_HF_GBP    cpu_to_be32(BIT(31))
 110
 111#define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | cpu_to_be32(0xFFFFFF))
 112
 113/* skb->mark mapping
 114 *
 115 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 116 * |R|R|R|R|R|R|R|R|R|D|R|R|A|R|R|R|        Group Policy ID        |
 117 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 118 */
 119#define VXLAN_GBP_DONT_LEARN            (BIT(6) << 16)
 120#define VXLAN_GBP_POLICY_APPLIED        (BIT(3) << 16)
 121#define VXLAN_GBP_ID_MASK               (0xFFFF)
 122
 123/*
 124 * VXLAN Generic Protocol Extension (VXLAN_F_GPE):
 125 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 126 * |R|R|Ver|I|P|R|O|       Reserved                |Next Protocol  |
 127 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 128 * |                VXLAN Network Identifier (VNI) |   Reserved    |
 129 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 130 *
 131 * Ver = Version. Indicates VXLAN GPE protocol version.
 132 *
 133 * P = Next Protocol Bit. The P bit is set to indicate that the
 134 *     Next Protocol field is present.
 135 *
 136 * O = OAM Flag Bit. The O bit is set to indicate that the packet
 137 *     is an OAM packet.
 138 *
 139 * Next Protocol = This 8 bit field indicates the protocol header
 140 * immediately following the VXLAN GPE header.
 141 *
 142 * https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-01
 143 */
 144
 145struct vxlanhdr_gpe {
 146#if defined(__LITTLE_ENDIAN_BITFIELD)
 147        u8      oam_flag:1,
 148                reserved_flags1:1,
 149                np_applied:1,
 150                instance_applied:1,
 151                version:2,
 152                reserved_flags2:2;
 153#elif defined(__BIG_ENDIAN_BITFIELD)
 154        u8      reserved_flags2:2,
 155                version:2,
 156                instance_applied:1,
 157                np_applied:1,
 158                reserved_flags1:1,
 159                oam_flag:1;
 160#endif
 161        u8      reserved_flags3;
 162        u8      reserved_flags4;
 163        u8      next_protocol;
 164        __be32  vx_vni;
 165};
 166
 167/* VXLAN-GPE header flags. */
 168#define VXLAN_HF_VER    cpu_to_be32(BIT(29) | BIT(28))
 169#define VXLAN_HF_NP     cpu_to_be32(BIT(26))
 170#define VXLAN_HF_OAM    cpu_to_be32(BIT(24))
 171
 172#define VXLAN_GPE_USED_BITS (VXLAN_HF_VER | VXLAN_HF_NP | VXLAN_HF_OAM | \
 173                             cpu_to_be32(0xff))
 174
 175struct vxlan_metadata {
 176        u32             gbp;
 177};
 178
 179/* per UDP socket information */
 180struct vxlan_sock {
 181        struct hlist_node hlist;
 182        struct socket    *sock;
 183        struct hlist_head vni_list[VNI_HASH_SIZE];
 184        refcount_t        refcnt;
 185        u32               flags;
 186};
 187
 188union vxlan_addr {
 189        struct sockaddr_in sin;
 190        struct sockaddr_in6 sin6;
 191        struct sockaddr sa;
 192};
 193
 194struct vxlan_rdst {
 195        union vxlan_addr         remote_ip;
 196        __be16                   remote_port;
 197        u8                       offloaded:1;
 198        __be32                   remote_vni;
 199        u32                      remote_ifindex;
 200        struct list_head         list;
 201        struct rcu_head          rcu;
 202        struct dst_cache         dst_cache;
 203};
 204
 205struct vxlan_config {
 206        union vxlan_addr        remote_ip;
 207        union vxlan_addr        saddr;
 208        __be32                  vni;
 209        int                     remote_ifindex;
 210        int                     mtu;
 211        __be16                  dst_port;
 212        u16                     port_min;
 213        u16                     port_max;
 214        u8                      tos;
 215        u8                      ttl;
 216        __be32                  label;
 217        u32                     flags;
 218        unsigned long           age_interval;
 219        unsigned int            addrmax;
 220        bool                    no_share;
 221        enum ifla_vxlan_df      df;
 222};
 223
 224struct vxlan_dev_node {
 225        struct hlist_node hlist;
 226        struct vxlan_dev *vxlan;
 227};
 228
 229/* Pseudo network device */
 230struct vxlan_dev {
 231        struct vxlan_dev_node hlist4;   /* vni hash table for IPv4 socket */
 232#if IS_ENABLED(CONFIG_IPV6)
 233        struct vxlan_dev_node hlist6;   /* vni hash table for IPv6 socket */
 234#endif
 235        struct list_head  next;         /* vxlan's per namespace list */
 236        struct vxlan_sock __rcu *vn4_sock;      /* listening socket for IPv4 */
 237#if IS_ENABLED(CONFIG_IPV6)
 238        struct vxlan_sock __rcu *vn6_sock;      /* listening socket for IPv6 */
 239#endif
 240        struct net_device *dev;
 241        struct net        *net;         /* netns for packet i/o */
 242        struct vxlan_rdst default_dst;  /* default destination */
 243
 244        struct timer_list age_timer;
 245        spinlock_t        hash_lock;
 246        unsigned int      addrcnt;
 247        struct gro_cells  gro_cells;
 248
 249        struct vxlan_config     cfg;
 250
 251        struct hlist_head fdb_head[FDB_HASH_SIZE];
 252};
 253
 254#define VXLAN_F_LEARN                   0x01
 255#define VXLAN_F_PROXY                   0x02
 256#define VXLAN_F_RSC                     0x04
 257#define VXLAN_F_L2MISS                  0x08
 258#define VXLAN_F_L3MISS                  0x10
 259#define VXLAN_F_IPV6                    0x20
 260#define VXLAN_F_UDP_ZERO_CSUM_TX        0x40
 261#define VXLAN_F_UDP_ZERO_CSUM6_TX       0x80
 262#define VXLAN_F_UDP_ZERO_CSUM6_RX       0x100
 263#define VXLAN_F_REMCSUM_TX              0x200
 264#define VXLAN_F_REMCSUM_RX              0x400
 265#define VXLAN_F_GBP                     0x800
 266#define VXLAN_F_REMCSUM_NOPARTIAL       0x1000
 267#define VXLAN_F_COLLECT_METADATA        0x2000
 268#define VXLAN_F_GPE                     0x4000
 269#define VXLAN_F_IPV6_LINKLOCAL          0x8000
 270#define VXLAN_F_TTL_INHERIT             0x10000
 271
 272/* Flags that are used in the receive path. These flags must match in
 273 * order for a socket to be shareable
 274 */
 275#define VXLAN_F_RCV_FLAGS               (VXLAN_F_GBP |                  \
 276                                         VXLAN_F_GPE |                  \
 277                                         VXLAN_F_UDP_ZERO_CSUM6_RX |    \
 278                                         VXLAN_F_REMCSUM_RX |           \
 279                                         VXLAN_F_REMCSUM_NOPARTIAL |    \
 280                                         VXLAN_F_COLLECT_METADATA)
 281
 282/* Flags that can be set together with VXLAN_F_GPE. */
 283#define VXLAN_F_ALLOWED_GPE             (VXLAN_F_GPE |                  \
 284                                         VXLAN_F_IPV6 |                 \
 285                                         VXLAN_F_IPV6_LINKLOCAL |       \
 286                                         VXLAN_F_UDP_ZERO_CSUM_TX |     \
 287                                         VXLAN_F_UDP_ZERO_CSUM6_TX |    \
 288                                         VXLAN_F_UDP_ZERO_CSUM6_RX |    \
 289                                         VXLAN_F_COLLECT_METADATA)
 290
 291struct net_device *vxlan_dev_create(struct net *net, const char *name,
 292                                    u8 name_assign_type, struct vxlan_config *conf);
 293
 294static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
 295                                                     netdev_features_t features)
 296{
 297        u8 l4_hdr = 0;
 298
 299        if (!skb->encapsulation)
 300                return features;
 301
 302        switch (vlan_get_protocol(skb)) {
 303        case htons(ETH_P_IP):
 304                l4_hdr = ip_hdr(skb)->protocol;
 305                break;
 306        case htons(ETH_P_IPV6):
 307                l4_hdr = ipv6_hdr(skb)->nexthdr;
 308                break;
 309        default:
 310                return features;
 311        }
 312
 313        if ((l4_hdr == IPPROTO_UDP) &&
 314            (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
 315             skb->inner_protocol != htons(ETH_P_TEB) ||
 316             (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
 317              sizeof(struct udphdr) + sizeof(struct vxlanhdr)) ||
 318             (skb->ip_summed != CHECKSUM_NONE &&
 319              !can_checksum_protocol(features, inner_eth_hdr(skb)->h_proto))))
 320                return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
 321
 322        return features;
 323}
 324
 325/* IP header + UDP + VXLAN + Ethernet header */
 326#define VXLAN_HEADROOM (20 + 8 + 8 + 14)
 327/* IPv6 header + UDP + VXLAN + Ethernet header */
 328#define VXLAN6_HEADROOM (40 + 8 + 8 + 14)
 329
 330static inline struct vxlanhdr *vxlan_hdr(struct sk_buff *skb)
 331{
 332        return (struct vxlanhdr *)(udp_hdr(skb) + 1);
 333}
 334
 335static inline __be32 vxlan_vni(__be32 vni_field)
 336{
 337#if defined(__BIG_ENDIAN)
 338        return (__force __be32)((__force u32)vni_field >> 8);
 339#else
 340        return (__force __be32)((__force u32)(vni_field & VXLAN_VNI_MASK) << 8);
 341#endif
 342}
 343
 344static inline __be32 vxlan_vni_field(__be32 vni)
 345{
 346#if defined(__BIG_ENDIAN)
 347        return (__force __be32)((__force u32)vni << 8);
 348#else
 349        return (__force __be32)((__force u32)vni >> 8);
 350#endif
 351}
 352
 353static inline size_t vxlan_rco_start(__be32 vni_field)
 354{
 355        return be32_to_cpu(vni_field & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT;
 356}
 357
 358static inline size_t vxlan_rco_offset(__be32 vni_field)
 359{
 360        return (vni_field & VXLAN_RCO_UDP) ?
 361                offsetof(struct udphdr, check) :
 362                offsetof(struct tcphdr, check);
 363}
 364
 365static inline __be32 vxlan_compute_rco(unsigned int start, unsigned int offset)
 366{
 367        __be32 vni_field = cpu_to_be32(start >> VXLAN_RCO_SHIFT);
 368
 369        if (offset == offsetof(struct udphdr, check))
 370                vni_field |= VXLAN_RCO_UDP;
 371        return vni_field;
 372}
 373
 374static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs)
 375{
 376        return vs->sock->sk->sk_family;
 377}
 378
 379#if IS_ENABLED(CONFIG_IPV6)
 380
 381static inline bool vxlan_addr_any(const union vxlan_addr *ipa)
 382{
 383        if (ipa->sa.sa_family == AF_INET6)
 384                return ipv6_addr_any(&ipa->sin6.sin6_addr);
 385        else
 386                return ipa->sin.sin_addr.s_addr == htonl(INADDR_ANY);
 387}
 388
 389static inline bool vxlan_addr_multicast(const union vxlan_addr *ipa)
 390{
 391        if (ipa->sa.sa_family == AF_INET6)
 392                return ipv6_addr_is_multicast(&ipa->sin6.sin6_addr);
 393        else
 394                return IN_MULTICAST(ntohl(ipa->sin.sin_addr.s_addr));
 395}
 396
 397#else /* !IS_ENABLED(CONFIG_IPV6) */
 398
 399static inline bool vxlan_addr_any(const union vxlan_addr *ipa)
 400{
 401        return ipa->sin.sin_addr.s_addr == htonl(INADDR_ANY);
 402}
 403
 404static inline bool vxlan_addr_multicast(const union vxlan_addr *ipa)
 405{
 406        return IN_MULTICAST(ntohl(ipa->sin.sin_addr.s_addr));
 407}
 408
 409#endif /* IS_ENABLED(CONFIG_IPV6) */
 410
 411static inline bool netif_is_vxlan(const struct net_device *dev)
 412{
 413        return dev->rtnl_link_ops &&
 414               !strcmp(dev->rtnl_link_ops->kind, "vxlan");
 415}
 416
 417struct switchdev_notifier_vxlan_fdb_info {
 418        struct switchdev_notifier_info info; /* must be first */
 419        union vxlan_addr remote_ip;
 420        __be16 remote_port;
 421        __be32 remote_vni;
 422        u32 remote_ifindex;
 423        u8 eth_addr[ETH_ALEN];
 424        __be32 vni;
 425        bool offloaded;
 426        bool added_by_user;
 427};
 428
 429#if IS_ENABLED(CONFIG_VXLAN)
 430int vxlan_fdb_find_uc(struct net_device *dev, const u8 *mac, __be32 vni,
 431                      struct switchdev_notifier_vxlan_fdb_info *fdb_info);
 432int vxlan_fdb_replay(const struct net_device *dev, __be32 vni,
 433                     struct notifier_block *nb,
 434                     struct netlink_ext_ack *extack);
 435void vxlan_fdb_clear_offload(const struct net_device *dev, __be32 vni);
 436
 437#else
 438static inline int
 439vxlan_fdb_find_uc(struct net_device *dev, const u8 *mac, __be32 vni,
 440                  struct switchdev_notifier_vxlan_fdb_info *fdb_info)
 441{
 442        return -ENOENT;
 443}
 444
 445static inline int vxlan_fdb_replay(const struct net_device *dev, __be32 vni,
 446                                   struct notifier_block *nb,
 447                                   struct netlink_ext_ack *extack)
 448{
 449        return -EOPNOTSUPP;
 450}
 451
 452static inline void
 453vxlan_fdb_clear_offload(const struct net_device *dev, __be32 vni)
 454{
 455}
 456#endif
 457
 458static inline void vxlan_flag_attr_error(int attrtype,
 459                                         struct netlink_ext_ack *extack)
 460{
 461#define VXLAN_FLAG(flg) \
 462        case IFLA_VXLAN_##flg: \
 463                NL_SET_ERR_MSG_MOD(extack, \
 464                                   "cannot change " #flg " flag"); \
 465                break
 466        switch (attrtype) {
 467        VXLAN_FLAG(TTL_INHERIT);
 468        VXLAN_FLAG(LEARNING);
 469        VXLAN_FLAG(PROXY);
 470        VXLAN_FLAG(RSC);
 471        VXLAN_FLAG(L2MISS);
 472        VXLAN_FLAG(L3MISS);
 473        VXLAN_FLAG(COLLECT_METADATA);
 474        VXLAN_FLAG(UDP_ZERO_CSUM6_TX);
 475        VXLAN_FLAG(UDP_ZERO_CSUM6_RX);
 476        VXLAN_FLAG(REMCSUM_TX);
 477        VXLAN_FLAG(REMCSUM_RX);
 478        VXLAN_FLAG(GBP);
 479        VXLAN_FLAG(GPE);
 480        VXLAN_FLAG(REMCSUM_NOPARTIAL);
 481        default:
 482                NL_SET_ERR_MSG_MOD(extack, \
 483                                   "cannot change flag");
 484                break;
 485        }
 486#undef VXLAN_FLAG
 487}
 488
 489#endif
 490