include/net/vxlan.h

   1 #ifndef __NET_VXLAN_H
   2 #define __NET_VXLAN_H 1
   3
   4 #include <linux/ip.h>
   5 #include <linux/ipv6.h>
   6 #include <linux/if_vlan.h>
   7 #include <linux/skbuff.h>
   8 #include <linux/netdevice.h>
   9 #include <linux/udp.h>
  10 #include <net/dst_metadata.h>
  11
  12 #define VNI_HASH_BITS   10
  13 #define VNI_HASH_SIZE   (1<<VNI_HASH_BITS)
  14
  15 /*
  16  * VXLAN Group Based Policy Extension:
  17  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  18  * |1|-|-|-|1|-|-|-|R|D|R|R|A|R|R|R|        Group Policy ID        |
  19  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  20  * |                VXLAN Network Identifier (VNI) |   Reserved    |
  21  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  22  *
  23  * D = Don't Learn bit. When set, this bit indicates that the egress
  24  *     VTEP MUST NOT learn the source address of the encapsulated frame.
  25  *
  26  * A = Indicates that the group policy has already been applied to
  27  *     this packet. Policies MUST NOT be applied by devices when the
  28  *     A bit is set.
  29  *
  30  * [0] https://tools.ietf.org/html/draft-smith-vxlan-group-policy
  31  */
  32 struct vxlanhdr_gbp {
  33         __u8    vx_flags;
  34 #ifdef __LITTLE_ENDIAN_BITFIELD
  35         __u8    reserved_flags1:3,
  36                 policy_applied:1,
  37                 reserved_flags2:2,
  38                 dont_learn:1,
  39                 reserved_flags3:1;
  40 #elif defined(__BIG_ENDIAN_BITFIELD)
  41         __u8    reserved_flags1:1,
  42                 dont_learn:1,
  43                 reserved_flags2:2,
  44                 policy_applied:1,
  45                 reserved_flags3:3;
  46 #else
  47 #error  "Please fix <asm/byteorder.h>"
  48 #endif
  49         __be16  policy_id;
  50         __be32  vx_vni;
  51 };
  52
  53 #define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | 0xFFFFFF)
  54
  55 /* skb->mark mapping
  56  *
  57  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  58  * |R|R|R|R|R|R|R|R|R|D|R|R|A|R|R|R|        Group Policy ID        |
  59  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  60  */
  61 #define VXLAN_GBP_DONT_LEARN            (BIT(6) << 16)
  62 #define VXLAN_GBP_POLICY_APPLIED        (BIT(3) << 16)
  63 #define VXLAN_GBP_ID_MASK               (0xFFFF)
  64
  65 /* VXLAN protocol header:
  66  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  67  * |G|R|R|R|I|R|R|C|               Reserved                        |
  68  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  69  * |                VXLAN Network Identifier (VNI) |   Reserved    |
  70  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  71  *
  72  * G = 1        Group Policy (VXLAN-GBP)
  73  * I = 1        VXLAN Network Identifier (VNI) present
  74  * C = 1        Remote checksum offload (RCO)
  75  */
  76 struct vxlanhdr {
  77         __be32 vx_flags;
  78         __be32 vx_vni;
  79 };
  80
  81 /* VXLAN header flags. */
  82 #define VXLAN_HF_RCO BIT(24)
  83 #define VXLAN_HF_VNI BIT(27)
  84 #define VXLAN_HF_GBP BIT(31)
  85
  86 /* Remote checksum offload header option */
  87 #define VXLAN_RCO_MASK  0x7f    /* Last byte of vni field */
  88 #define VXLAN_RCO_UDP   0x80    /* Indicate UDP RCO (TCP when not set *) */
  89 #define VXLAN_RCO_SHIFT 1       /* Left shift of start */
  90 #define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1)
  91 #define VXLAN_MAX_REMCSUM_START (VXLAN_RCO_MASK << VXLAN_RCO_SHIFT)
  92
  93 #define VXLAN_N_VID     (1u << 24)
  94 #define VXLAN_VID_MASK  (VXLAN_N_VID - 1)
  95 #define VXLAN_VNI_MASK  (VXLAN_VID_MASK << 8)
  96 #define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
  97
  98 #define VNI_HASH_BITS   10
  99 #define VNI_HASH_SIZE   (1<<VNI_HASH_BITS)
 100 #define FDB_HASH_BITS   8
 101 #define FDB_HASH_SIZE   (1<<FDB_HASH_BITS)
 102
 103 struct vxlan_metadata {
 104         u32             gbp;
 105 };
 106
 107 /* per UDP socket information */
 108 struct vxlan_sock {
 109         struct hlist_node hlist;
 110         struct work_struct del_work;
 111         struct socket    *sock;
 112         struct rcu_head   rcu;
 113         struct hlist_head vni_list[VNI_HASH_SIZE];
 114         atomic_t          refcnt;
 115         struct udp_offload udp_offloads;
 116         u32               flags;
 117 };
 118
 119 union vxlan_addr {
 120         struct sockaddr_in sin;
 121         struct sockaddr_in6 sin6;
 122         struct sockaddr sa;
 123 };
 124
 125 struct vxlan_rdst {
 126         union vxlan_addr         remote_ip;
 127         __be16                   remote_port;
 128         u32                      remote_vni;
 129         u32                      remote_ifindex;
 130         struct list_head         list;
 131         struct rcu_head          rcu;
 132 };
 133
 134 struct vxlan_config {
 135         union vxlan_addr        remote_ip;
 136         union vxlan_addr        saddr;
 137         u32                     vni;
 138         int                     remote_ifindex;
 139         int                     mtu;
 140         __be16                  dst_port;
 141         __u16                   port_min;
 142         __u16                   port_max;
 143         __u8                    tos;
 144         __u8                    ttl;
 145         u32                     flags;
 146         unsigned long           age_interval;
 147         unsigned int            addrmax;
 148         bool                    no_share;
 149 };
 150
 151 /* Pseudo network device */
 152 struct vxlan_dev {
 153         struct hlist_node hlist;        /* vni hash table */
 154         struct list_head  next;         /* vxlan's per namespace list */
 155         struct vxlan_sock *vn4_sock;    /* listening socket for IPv4 */
 156 #if IS_ENABLED(CONFIG_IPV6)
 157         struct vxlan_sock *vn6_sock;    /* listening socket for IPv6 */
 158 #endif
 159         struct net_device *dev;
 160         struct net        *net;         /* netns for packet i/o */
 161         struct vxlan_rdst default_dst;  /* default destination */
 162         u32               flags;        /* VXLAN_F_* in vxlan.h */
 163
 164         struct timer_list age_timer;
 165         spinlock_t        hash_lock;
 166         unsigned int      addrcnt;
 167         struct gro_cells  gro_cells;
 168
 169         struct vxlan_config     cfg;
 170
 171         struct hlist_head fdb_head[FDB_HASH_SIZE];
 172 };
 173
 174 #define VXLAN_F_LEARN                   0x01
 175 #define VXLAN_F_PROXY                   0x02
 176 #define VXLAN_F_RSC                     0x04
 177 #define VXLAN_F_L2MISS                  0x08
 178 #define VXLAN_F_L3MISS                  0x10
 179 #define VXLAN_F_IPV6                    0x20
 180 #define VXLAN_F_UDP_CSUM                0x40
 181 #define VXLAN_F_UDP_ZERO_CSUM6_TX       0x80
 182 #define VXLAN_F_UDP_ZERO_CSUM6_RX       0x100
 183 #define VXLAN_F_REMCSUM_TX              0x200
 184 #define VXLAN_F_REMCSUM_RX              0x400
 185 #define VXLAN_F_GBP                     0x800
 186 #define VXLAN_F_REMCSUM_NOPARTIAL       0x1000
 187 #define VXLAN_F_COLLECT_METADATA        0x2000
 188
 189 /* Flags that are used in the receive path. These flags must match in
 190  * order for a socket to be shareable
 191  */
 192 #define VXLAN_F_RCV_FLAGS               (VXLAN_F_GBP |                  \
 193                                          VXLAN_F_UDP_ZERO_CSUM6_RX |    \
 194                                          VXLAN_F_REMCSUM_RX |           \
 195                                          VXLAN_F_REMCSUM_NOPARTIAL |    \
 196                                          VXLAN_F_COLLECT_METADATA)
 197
 198 struct net_device *vxlan_dev_create(struct net *net, const char *name,
 199                                     u8 name_assign_type, struct vxlan_config *conf);
 200
 201 static inline __be16 vxlan_dev_dst_port(struct vxlan_dev *vxlan,
 202                                         unsigned short family)
 203 {
 204 #if IS_ENABLED(CONFIG_IPV6)
 205         if (family == AF_INET6)
 206                 return inet_sk(vxlan->vn6_sock->sock->sk)->inet_sport;
 207 #endif
 208         return inet_sk(vxlan->vn4_sock->sock->sk)->inet_sport;
 209 }
 210
 211 static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
 212                                                      netdev_features_t features)
 213 {
 214         u8 l4_hdr = 0;
 215
 216         if (!skb->encapsulation)
 217                 return features;
 218
 219         switch (vlan_get_protocol(skb)) {
 220         case htons(ETH_P_IP):
 221                 l4_hdr = ip_hdr(skb)->protocol;
 222                 break;
 223         case htons(ETH_P_IPV6):
 224                 l4_hdr = ipv6_hdr(skb)->nexthdr;
 225                 break;
 226         default:
 227                 return features;;
 228         }
 229
 230         if ((l4_hdr == IPPROTO_UDP) &&
 231             (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
 232              skb->inner_protocol != htons(ETH_P_TEB) ||
 233              (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
 234               sizeof(struct udphdr) + sizeof(struct vxlanhdr))))
 235                 return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK);
 236
 237         return features;
 238 }
 239
 240 /* IP header + UDP + VXLAN + Ethernet header */
 241 #define VXLAN_HEADROOM (20 + 8 + 8 + 14)
 242 /* IPv6 header + UDP + VXLAN + Ethernet header */
 243 #define VXLAN6_HEADROOM (40 + 8 + 8 + 14)
 244
 245 #if IS_ENABLED(CONFIG_VXLAN)
 246 void vxlan_get_rx_port(struct net_device *netdev);
 247 #else
 248 static inline void vxlan_get_rx_port(struct net_device *netdev)
 249 {
 250 }
 251 #endif
 252
 253 static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs)
 254 {
 255         return vs->sock->sk->sk_family;
 256 }
 257
 258 #endif