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_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
  95
  96 struct vxlan_metadata {
  97         __be32          vni;
  98         u32             gbp;
  99 };
 100
 101 struct vxlan_sock;
 102 typedef void (vxlan_rcv_t)(struct vxlan_sock *vh, struct sk_buff *skb,
 103                            struct vxlan_metadata *md);
 104
 105 /* per UDP socket information */
 106 struct vxlan_sock {
 107         struct hlist_node hlist;
 108         vxlan_rcv_t      *rcv;
 109         void             *data;
 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 #define VXLAN_F_LEARN                   0x01
 120 #define VXLAN_F_PROXY                   0x02
 121 #define VXLAN_F_RSC                     0x04
 122 #define VXLAN_F_L2MISS                  0x08
 123 #define VXLAN_F_L3MISS                  0x10
 124 #define VXLAN_F_IPV6                    0x20
 125 #define VXLAN_F_UDP_CSUM                0x40
 126 #define VXLAN_F_UDP_ZERO_CSUM6_TX       0x80
 127 #define VXLAN_F_UDP_ZERO_CSUM6_RX       0x100
 128 #define VXLAN_F_REMCSUM_TX              0x200
 129 #define VXLAN_F_REMCSUM_RX              0x400
 130 #define VXLAN_F_GBP                     0x800
 131
 132 /* Flags that are used in the receive patch. These flags must match in
 133  * order for a socket to be shareable
 134  */
 135 #define VXLAN_F_RCV_FLAGS               (VXLAN_F_GBP |                  \
 136                                          VXLAN_F_UDP_ZERO_CSUM6_RX |    \
 137                                          VXLAN_F_REMCSUM_RX)
 138
 139 struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
 140                                   vxlan_rcv_t *rcv, void *data,
 141                                   bool no_share, u32 flags);
 142
 143 void vxlan_sock_release(struct vxlan_sock *vs);
 144
 145 int vxlan_xmit_skb(struct rtable *rt, struct sk_buff *skb,
 146                    __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
 147                    __be16 src_port, __be16 dst_port, struct vxlan_metadata *md,
 148                    bool xnet, u32 vxflags);
 149
 150 static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
 151                                                      netdev_features_t features)
 152 {
 153         u8 l4_hdr = 0;
 154
 155         if (!skb->encapsulation)
 156                 return features;
 157
 158         switch (vlan_get_protocol(skb)) {
 159         case htons(ETH_P_IP):
 160                 l4_hdr = ip_hdr(skb)->protocol;
 161                 break;
 162         case htons(ETH_P_IPV6):
 163                 l4_hdr = ipv6_hdr(skb)->nexthdr;
 164                 break;
 165         default:
 166                 return features;;
 167         }
 168
 169         if ((l4_hdr == IPPROTO_UDP) &&
 170             (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
 171              skb->inner_protocol != htons(ETH_P_TEB) ||
 172              (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
 173               sizeof(struct udphdr) + sizeof(struct vxlanhdr))))
 174                 return features & ~(NETIF_F_ALL_CSUM | NETIF_F_GSO_MASK);
 175
 176         return features;
 177 }
 178
 179 /* IP header + UDP + VXLAN + Ethernet header */
 180 #define VXLAN_HEADROOM (20 + 8 + 8 + 14)
 181 /* IPv6 header + UDP + VXLAN + Ethernet header */
 182 #define VXLAN6_HEADROOM (40 + 8 + 8 + 14)
 183
 184 #if IS_ENABLED(CONFIG_VXLAN)
 185 void vxlan_get_rx_port(struct net_device *netdev);
 186 #else
 187 static inline void vxlan_get_rx_port(struct net_device *netdev)
 188 {
 189 }
 190 #endif
 191 #endif