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 net_device        *remote_dev;
 201        struct list_head         list;
 202        struct rcu_head          rcu;
 203        struct dst_cache         dst_cache;
 204};
 205
 206struct vxlan_config {
 207        union vxlan_addr        remote_ip;
 208        union vxlan_addr        saddr;
 209        __be32                  vni;
 210        int                     remote_ifindex;
 211        int                     mtu;
 212        __be16                  dst_port;
 213        u16                     port_min;
 214        u16                     port_max;
 215        u8                      tos;
 216        u8                      ttl;
 217        __be32                  label;
 218        u32                     flags;
 219        unsigned long           age_interval;
 220        unsigned int            addrmax;
 221        bool                    no_share;
 222        enum ifla_vxlan_df      df;
 223};
 224
 225struct vxlan_dev_node {
 226        struct hlist_node hlist;
 227        struct vxlan_dev *vxlan;
 228};
 229
 230/* Pseudo network device */
 231struct vxlan_dev {
 232        struct vxlan_dev_node hlist4;   /* vni hash table for IPv4 socket */
 233#if IS_ENABLED(CONFIG_IPV6)
 234        struct vxlan_dev_node hlist6;   /* vni hash table for IPv6 socket */
 235#endif
 236        struct list_head  next;         /* vxlan's per namespace list */
 237        struct vxlan_sock __rcu *vn4_sock;      /* listening socket for IPv4 */
 238#if IS_ENABLED(CONFIG_IPV6)
 239        struct vxlan_sock __rcu *vn6_sock;      /* listening socket for IPv6 */
 240#endif
 241        struct net_device *dev;
 242        struct net        *net;         /* netns for packet i/o */
 243        struct vxlan_rdst default_dst;  /* default destination */
 244
 245        struct timer_list age_timer;
 246        spinlock_t        hash_lock[FDB_HASH_SIZE];
 247        unsigned int      addrcnt;
 248        struct gro_cells  gro_cells;
 249
 250        struct vxlan_config     cfg;
 251
 252        struct hlist_head fdb_head[FDB_HASH_SIZE];
 253};
 254
 255#define VXLAN_F_LEARN                   0x01
 256#define VXLAN_F_PROXY                   0x02
 257#define VXLAN_F_RSC                     0x04
 258#define VXLAN_F_L2MISS                  0x08
 259#define VXLAN_F_L3MISS                  0x10
 260#define VXLAN_F_IPV6                    0x20
 261#define VXLAN_F_UDP_ZERO_CSUM_TX        0x40
 262#define VXLAN_F_UDP_ZERO_CSUM6_TX       0x80
 263#define VXLAN_F_UDP_ZERO_CSUM6_RX       0x100
 264#define VXLAN_F_REMCSUM_TX              0x200
 265#define VXLAN_F_REMCSUM_RX              0x400
 266#define VXLAN_F_GBP                     0x800
 267#define VXLAN_F_REMCSUM_NOPARTIAL       0x1000
 268#define VXLAN_F_COLLECT_METADATA        0x2000
 269#define VXLAN_F_GPE                     0x4000
 270#define VXLAN_F_IPV6_LINKLOCAL          0x8000
 271#define VXLAN_F_TTL_INHERIT             0x10000
 272
 273/* Flags that are used in the receive path. These flags must match in
 274 * order for a socket to be shareable
 275 */
 276#define VXLAN_F_RCV_FLAGS               (VXLAN_F_GBP |                  \
 277                                         VXLAN_F_GPE |                  \
 278                                         VXLAN_F_UDP_ZERO_CSUM6_RX |    \
 279                                         VXLAN_F_REMCSUM_RX |           \
 280                                         VXLAN_F_REMCSUM_NOPARTIAL |    \
 281                                         VXLAN_F_COLLECT_METADATA)
 282
 283/* Flags that can be set together with VXLAN_F_GPE. */
 284#define VXLAN_F_ALLOWED_GPE             (VXLAN_F_GPE |                  \
 285                                         VXLAN_F_IPV6 |                 \
 286                                         VXLAN_F_IPV6_LINKLOCAL |       \
 287                                         VXLAN_F_UDP_ZERO_CSUM_TX |     \
 288                                         VXLAN_F_UDP_ZERO_CSUM6_TX |    \
 289                                         VXLAN_F_UDP_ZERO_CSUM6_RX |    \
 290                                         VXLAN_F_COLLECT_METADATA)
 291
 292struct net_device *vxlan_dev_create(struct net *net, const char *name,
 293                                    u8 name_assign_type, struct vxlan_config *conf);
 294
 295static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
 296                                                     netdev_features_t features)
 297{
 298        u8 l4_hdr = 0;
 299
 300        if (!skb->encapsulation)
 301                return features;
 302
 303        switch (vlan_get_protocol(skb)) {
 304        case htons(ETH_P_IP):
 305                l4_hdr = ip_hdr(skb)->protocol;
 306                break;
 307        case htons(ETH_P_IPV6):
 308                l4_hdr = ipv6_hdr(skb)->nexthdr;
 309                break;
 310        default:
 311                return features;
 312        }
 313
 314        if ((l4_hdr == IPPROTO_UDP) &&
 315            (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
 316             skb->inner_protocol != htons(ETH_P_TEB) ||
 317             (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
 318              sizeof(struct udphdr) + sizeof(struct vxlanhdr)) ||
 319             (skb->ip_summed != CHECKSUM_NONE &&
 320              !can_checksum_protocol(features, inner_eth_hdr(skb)->h_proto))))
 321                return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
 322
 323        return features;
 324}
 325
 326/* IP header + UDP + VXLAN + Ethernet header */
 327#define VXLAN_HEADROOM (20 + 8 + 8 + 14)
 328/* IPv6 header + UDP + VXLAN + Ethernet header */
 329#define VXLAN6_HEADROOM (40 + 8 + 8 + 14)
 330
 331static inline struct vxlanhdr *vxlan_hdr(struct sk_buff *skb)
 332{
 333        return (struct vxlanhdr *)(udp_hdr(skb) + 1);
 334}
 335
 336static inline __be32 vxlan_vni(__be32 vni_field)
 337{
 338#if defined(__BIG_ENDIAN)
 339        return (__force __be32)((__force u32)vni_field >> 8);
 340#else
 341        return (__force __be32)((__force u32)(vni_field & VXLAN_VNI_MASK) << 8);
 342#endif
 343}
 344
 345static inline __be32 vxlan_vni_field(__be32 vni)
 346{
 347#if defined(__BIG_ENDIAN)
 348        return (__force __be32)((__force u32)vni << 8);
 349#else
 350        return (__force __be32)((__force u32)vni >> 8);
 351#endif
 352}
 353
 354static inline size_t vxlan_rco_start(__be32 vni_field)
 355{
 356        return be32_to_cpu(vni_field & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT;
 357}
 358
 359static inline size_t vxlan_rco_offset(__be32 vni_field)
 360{
 361        return (vni_field & VXLAN_RCO_UDP) ?
 362                offsetof(struct udphdr, check) :
 363                offsetof(struct tcphdr, check);
 364}
 365
 366static inline __be32 vxlan_compute_rco(unsigned int start, unsigned int offset)
 367{
 368        __be32 vni_field = cpu_to_be32(start >> VXLAN_RCO_SHIFT);
 369
 370        if (offset == offsetof(struct udphdr, check))
 371                vni_field |= VXLAN_RCO_UDP;
 372        return vni_field;
 373}
 374
 375static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs)
 376{
 377        return vs->sock->sk->sk_family;
 378}
 379
 380#if IS_ENABLED(CONFIG_IPV6)
 381
 382static inline bool vxlan_addr_any(const union vxlan_addr *ipa)
 383{
 384        if (ipa->sa.sa_family == AF_INET6)
 385                return ipv6_addr_any(&ipa->sin6.sin6_addr);
 386        else
 387                return ipa->sin.sin_addr.s_addr == htonl(INADDR_ANY);
 388}
 389
 390static inline bool vxlan_addr_multicast(const union vxlan_addr *ipa)
 391{
 392        if (ipa->sa.sa_family == AF_INET6)
 393                return ipv6_addr_is_multicast(&ipa->sin6.sin6_addr);
 394        else
 395                return ipv4_is_multicast(ipa->sin.sin_addr.s_addr);
 396}
 397
 398#else /* !IS_ENABLED(CONFIG_IPV6) */
 399
 400static inline bool vxlan_addr_any(const union vxlan_addr *ipa)
 401{
 402        return ipa->sin.sin_addr.s_addr == htonl(INADDR_ANY);
 403}
 404
 405static inline bool vxlan_addr_multicast(const union vxlan_addr *ipa)
 406{
 407        return ipv4_is_multicast(ipa->sin.sin_addr.s_addr);
 408}
 409
 410#endif /* IS_ENABLED(CONFIG_IPV6) */
 411
 412static inline bool netif_is_vxlan(const struct net_device *dev)
 413{
 414        return dev->rtnl_link_ops &&
 415               !strcmp(dev->rtnl_link_ops->kind, "vxlan");
 416}
 417
 418struct switchdev_notifier_vxlan_fdb_info {
 419        struct switchdev_notifier_info info; /* must be first */
 420        union vxlan_addr remote_ip;
 421        __be16 remote_port;
 422        __be32 remote_vni;
 423        u32 remote_ifindex;
 424        u8 eth_addr[ETH_ALEN];
 425        __be32 vni;
 426        bool offloaded;
 427        bool added_by_user;
 428};
 429
 430#if IS_ENABLED(CONFIG_VXLAN)
 431int vxlan_fdb_find_uc(struct net_device *dev, const u8 *mac, __be32 vni,
 432                      struct switchdev_notifier_vxlan_fdb_info *fdb_info);
 433int vxlan_fdb_replay(const struct net_device *dev, __be32 vni,
 434                     struct notifier_block *nb,
 435                     struct netlink_ext_ack *extack);
 436void vxlan_fdb_clear_offload(const struct net_device *dev, __be32 vni);
 437
 438#else
 439static inline int
 440vxlan_fdb_find_uc(struct net_device *dev, const u8 *mac, __be32 vni,
 441                  struct switchdev_notifier_vxlan_fdb_info *fdb_info)
 442{
 443        return -ENOENT;
 444}
 445
 446static inline int vxlan_fdb_replay(const struct net_device *dev, __be32 vni,
 447                                   struct notifier_block *nb,
 448                                   struct netlink_ext_ack *extack)
 449{
 450        return -EOPNOTSUPP;
 451}
 452
 453static inline void
 454vxlan_fdb_clear_offload(const struct net_device *dev, __be32 vni)
 455{
 456}
 457#endif
 458
 459static inline void vxlan_flag_attr_error(int attrtype,
 460                                         struct netlink_ext_ack *extack)
 461{
 462#define VXLAN_FLAG(flg) \
 463        case IFLA_VXLAN_##flg: \
 464                NL_SET_ERR_MSG_MOD(extack, \
 465                                   "cannot change " #flg " flag"); \
 466                break
 467        switch (attrtype) {
 468        VXLAN_FLAG(TTL_INHERIT);
 469        VXLAN_FLAG(LEARNING);
 470        VXLAN_FLAG(PROXY);
 471        VXLAN_FLAG(RSC);
 472        VXLAN_FLAG(L2MISS);
 473        VXLAN_FLAG(L3MISS);
 474        VXLAN_FLAG(COLLECT_METADATA);
 475        VXLAN_FLAG(UDP_ZERO_CSUM6_TX);
 476        VXLAN_FLAG(UDP_ZERO_CSUM6_RX);
 477        VXLAN_FLAG(REMCSUM_TX);
 478        VXLAN_FLAG(REMCSUM_RX);
 479        VXLAN_FLAG(GBP);
 480        VXLAN_FLAG(GPE);
 481        VXLAN_FLAG(REMCSUM_NOPARTIAL);
 482        default:
 483                NL_SET_ERR_MSG_MOD(extack, \
 484                                   "cannot change flag");
 485                break;
 486        }
 487#undef VXLAN_FLAG
 488}
 489
 490#endif
 491