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
  11 #define VNI_HASH_BITS   10
  12 #define VNI_HASH_SIZE   (1<<VNI_HASH_BITS)
  13
  14 /*
  15  * VXLAN Group Based Policy Extension:
  16  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  17  * |1|-|-|-|1|-|-|-|R|D|R|R|A|R|R|R|        Group Policy ID        |
  18  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  19  * |                VXLAN Network Identifier (VNI) |   Reserved    |
  20  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  21  *
  22  * D = Don't Learn bit. When set, this bit indicates that the egress
  23  *     VTEP MUST NOT learn the source address of the encapsulated frame.
  24  *
  25  * A = Indicates that the group policy has already been applied to
  26  *     this packet. Policies MUST NOT be applied by devices when the
  27  *     A bit is set.
  28  *
  29  * [0] https://tools.ietf.org/html/draft-smith-vxlan-group-policy
  30  */
  31 struct vxlanhdr_gbp {
  32         __u8    vx_flags;
  33 #ifdef __LITTLE_ENDIAN_BITFIELD
  34         __u8    reserved_flags1:3,
  35                 policy_applied:1,
  36                 reserved_flags2:2,
  37                 dont_learn:1,
  38                 reserved_flags3:1;
  39 #elif defined(__BIG_ENDIAN_BITFIELD)
  40         __u8    reserved_flags1:1,
  41                 dont_learn:1,
  42                 reserved_flags2:2,
  43                 policy_applied:1,
  44                 reserved_flags3:3;
  45 #else
  46 #error  "Please fix <asm/byteorder.h>"
  47 #endif
  48         __be16  policy_id;
  49         __be32  vx_vni;
  50 };
  51
  52 #define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | 0xFFFFFF)
  53
  54 /* skb->mark mapping
  55  *
  56  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  57  * |R|R|R|R|R|R|R|R|R|D|R|R|A|R|R|R|        Group Policy ID        |
  58  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  59  */
  60 #define VXLAN_GBP_DONT_LEARN            (BIT(6) << 16)
  61 #define VXLAN_GBP_POLICY_APPLIED        (BIT(3) << 16)
  62 #define VXLAN_GBP_ID_MASK               (0xFFFF)
  63
  64 /* VXLAN protocol header:
  65  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  66  * |G|R|R|R|I|R|R|C|               Reserved                        |
  67  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  68  * |                VXLAN Network Identifier (VNI) |   Reserved    |
  69  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  70  *
  71  * G = 1        Group Policy (VXLAN-GBP)
  72  * I = 1        VXLAN Network Identifier (VNI) present
  73  * C = 1        Remote checksum offload (RCO)
  74  */
  75 struct vxlanhdr {
  76         __be32 vx_flags;
  77         __be32 vx_vni;
  78 };
  79
  80 /* VXLAN header flags. */
  81 #define VXLAN_HF_RCO BIT(24)
  82 #define VXLAN_HF_VNI BIT(27)
  83 #define VXLAN_HF_GBP BIT(31)
  84
  85 /* Remote checksum offload header option */
  86 #define VXLAN_RCO_MASK  0x7f    /* Last byte of vni field */
  87 #define VXLAN_RCO_UDP   0x80    /* Indicate UDP RCO (TCP when not set *) */
  88 #define VXLAN_RCO_SHIFT 1       /* Left shift of start */
  89 #define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1)
  90 #define VXLAN_MAX_REMCSUM_START (VXLAN_RCO_MASK << VXLAN_RCO_SHIFT)
  91
  92 #define VXLAN_N_VID     (1u << 24)
  93 #define VXLAN_VID_MASK  (VXLAN_N_VID - 1)
  94 #define VXLAN_VNI_MASK  (VXLAN_VID_MASK << 8)
  95 #define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
  96
  97 struct vxlan_metadata {
  98         __be32          vni;
  99         u32             gbp;
 100 };
 101
 102 struct vxlan_sock;
 103 typedef void (vxlan_rcv_t)(struct vxlan_sock *vh, struct sk_buff *skb,
 104                            struct vxlan_metadata *md);
 105
 106 /* per UDP socket information */
 107 struct vxlan_sock {
 108         struct hlist_node hlist;
 109         vxlan_rcv_t      *rcv;
 110         void             *data;
 111         struct work_struct del_work;
 112         struct socket    *sock;
 113         struct rcu_head   rcu;
 114         struct hlist_head vni_list[VNI_HASH_SIZE];
 115         atomic_t          refcnt;
 116         struct udp_offload udp_offloads;
 117         u32               flags;
 118 };
 119
 120 #define VXLAN_F_LEARN                   0x01
 121 #define VXLAN_F_PROXY                   0x02
 122 #define VXLAN_F_RSC                     0x04
 123 #define VXLAN_F_L2MISS                  0x08
 124 #define VXLAN_F_L3MISS                  0x10
 125 #define VXLAN_F_IPV6                    0x20
 126 #define VXLAN_F_UDP_CSUM                0x40
 127 #define VXLAN_F_UDP_ZERO_CSUM6_TX       0x80
 128 #define VXLAN_F_UDP_ZERO_CSUM6_RX       0x100
 129 #define VXLAN_F_REMCSUM_TX              0x200
 130 #define VXLAN_F_REMCSUM_RX              0x400
 131 #define VXLAN_F_GBP                     0x800
 132 #define VXLAN_F_REMCSUM_NOPARTIAL       0x1000
 133
 134 /* Flags that are used in the receive path. These flags must match in
 135  * order for a socket to be shareable
 136  */
 137 #define VXLAN_F_RCV_FLAGS               (VXLAN_F_GBP |                  \
 138                                          VXLAN_F_UDP_ZERO_CSUM6_RX |    \
 139                                          VXLAN_F_REMCSUM_RX |           \
 140                                          VXLAN_F_REMCSUM_NOPARTIAL)
 141
 142 struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
 143                                   vxlan_rcv_t *rcv, void *data,
 144                                   bool no_share, u32 flags);
 145
 146 void vxlan_sock_release(struct vxlan_sock *vs);
 147
 148 int vxlan_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
 149                    __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
 150                    __be16 src_port, __be16 dst_port, struct vxlan_metadata *md,
 151                    bool xnet, u32 vxflags);
 152
 153 static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
 154                                                      netdev_features_t features)
 155 {
 156         u8 l4_hdr = 0;
 157
 158         if (!skb->encapsulation)
 159                 return features;
 160
 161         switch (vlan_get_protocol(skb)) {
 162         case htons(ETH_P_IP):
 163                 l4_hdr = ip_hdr(skb)->protocol;
 164                 break;
 165         case htons(ETH_P_IPV6):
 166                 l4_hdr = ipv6_hdr(skb)->nexthdr;
 167                 break;
 168         default:
 169                 return features;;
 170         }
 171
 172         if ((l4_hdr == IPPROTO_UDP) &&
 173             (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
 174              skb->inner_protocol != htons(ETH_P_TEB) ||
 175              (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
 176               sizeof(struct udphdr) + sizeof(struct vxlanhdr))))
 177                 return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK);
 178
 179         return features;
 180 }
 181
 182 /* IP header + UDP + VXLAN + Ethernet header */
 183 #define VXLAN_HEADROOM (20 + 8 + 8 + 14)
 184 /* IPv6 header + UDP + VXLAN + Ethernet header */
 185 #define VXLAN6_HEADROOM (40 + 8 + 8 + 14)
 186
 187 #if IS_ENABLED(CONFIG_VXLAN)
 188 void vxlan_get_rx_port(struct net_device *netdev);
 189 #else
 190 static inline void vxlan_get_rx_port(struct net_device *netdev)
 191 {
 192 }
 193 #endif
 194 #endif