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Diffstat (limited to 'include/net/vxlan.h')
-rw-r--r-- | include/net/vxlan.h | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/include/net/vxlan.h b/include/net/vxlan.h new file mode 100644 index 000000000..b99a02ae3 --- /dev/null +++ b/include/net/vxlan.h @@ -0,0 +1,374 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __NET_VXLAN_H +#define __NET_VXLAN_H 1 + +#include <linux/if_vlan.h> +#include <net/udp_tunnel.h> +#include <net/dst_metadata.h> +#include <net/udp_tunnel.h> + +/* VXLAN protocol (RFC 7348) header: + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |R|R|R|R|I|R|R|R| Reserved | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | VXLAN Network Identifier (VNI) | Reserved | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + * I = VXLAN Network Identifier (VNI) present. + */ +struct vxlanhdr { + __be32 vx_flags; + __be32 vx_vni; +}; + +/* VXLAN header flags. */ +#define VXLAN_HF_VNI cpu_to_be32(BIT(27)) + +#define VXLAN_N_VID (1u << 24) +#define VXLAN_VID_MASK (VXLAN_N_VID - 1) +#define VXLAN_VNI_MASK cpu_to_be32(VXLAN_VID_MASK << 8) +#define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr)) + +#define VNI_HASH_BITS 10 +#define VNI_HASH_SIZE (1<<VNI_HASH_BITS) +#define FDB_HASH_BITS 8 +#define FDB_HASH_SIZE (1<<FDB_HASH_BITS) + +/* Remote checksum offload for VXLAN (VXLAN_F_REMCSUM_[RT]X): + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |R|R|R|R|I|R|R|R|R|R|C| Reserved | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | VXLAN Network Identifier (VNI) |O| Csum start | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + * C = Remote checksum offload bit. When set indicates that the + * remote checksum offload data is present. + * + * O = Offset bit. Indicates the checksum offset relative to + * checksum start. + * + * Csum start = Checksum start divided by two. + * + * http://tools.ietf.org/html/draft-herbert-vxlan-rco + */ + +/* VXLAN-RCO header flags. */ +#define VXLAN_HF_RCO cpu_to_be32(BIT(21)) + +/* Remote checksum offload header option */ +#define VXLAN_RCO_MASK cpu_to_be32(0x7f) /* Last byte of vni field */ +#define VXLAN_RCO_UDP cpu_to_be32(0x80) /* Indicate UDP RCO (TCP when not set *) */ +#define VXLAN_RCO_SHIFT 1 /* Left shift of start */ +#define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1) +#define VXLAN_MAX_REMCSUM_START (0x7f << VXLAN_RCO_SHIFT) + +/* + * VXLAN Group Based Policy Extension (VXLAN_F_GBP): + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |G|R|R|R|I|R|R|R|R|D|R|R|A|R|R|R| Group Policy ID | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | VXLAN Network Identifier (VNI) | Reserved | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + * G = Group Policy ID present. + * + * D = Don't Learn bit. When set, this bit indicates that the egress + * VTEP MUST NOT learn the source address of the encapsulated frame. + * + * A = Indicates that the group policy has already been applied to + * this packet. Policies MUST NOT be applied by devices when the + * A bit is set. + * + * https://tools.ietf.org/html/draft-smith-vxlan-group-policy + */ +struct vxlanhdr_gbp { + u8 vx_flags; +#ifdef __LITTLE_ENDIAN_BITFIELD + u8 reserved_flags1:3, + policy_applied:1, + reserved_flags2:2, + dont_learn:1, + reserved_flags3:1; +#elif defined(__BIG_ENDIAN_BITFIELD) + u8 reserved_flags1:1, + dont_learn:1, + reserved_flags2:2, + policy_applied:1, + reserved_flags3:3; +#else +#error "Please fix <asm/byteorder.h>" +#endif + __be16 policy_id; + __be32 vx_vni; +}; + +/* VXLAN-GBP header flags. */ +#define VXLAN_HF_GBP cpu_to_be32(BIT(31)) + +#define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | cpu_to_be32(0xFFFFFF)) + +/* skb->mark mapping + * + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |R|R|R|R|R|R|R|R|R|D|R|R|A|R|R|R| Group Policy ID | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ +#define VXLAN_GBP_DONT_LEARN (BIT(6) << 16) +#define VXLAN_GBP_POLICY_APPLIED (BIT(3) << 16) +#define VXLAN_GBP_ID_MASK (0xFFFF) + +/* + * VXLAN Generic Protocol Extension (VXLAN_F_GPE): + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |R|R|Ver|I|P|R|O| Reserved |Next Protocol | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * | VXLAN Network Identifier (VNI) | Reserved | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * + * Ver = Version. Indicates VXLAN GPE protocol version. + * + * P = Next Protocol Bit. The P bit is set to indicate that the + * Next Protocol field is present. + * + * O = OAM Flag Bit. The O bit is set to indicate that the packet + * is an OAM packet. + * + * Next Protocol = This 8 bit field indicates the protocol header + * immediately following the VXLAN GPE header. + * + * https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-01 + */ + +struct vxlanhdr_gpe { +#if defined(__LITTLE_ENDIAN_BITFIELD) + u8 oam_flag:1, + reserved_flags1:1, + np_applied:1, + instance_applied:1, + version:2, + reserved_flags2:2; +#elif defined(__BIG_ENDIAN_BITFIELD) + u8 reserved_flags2:2, + version:2, + instance_applied:1, + np_applied:1, + reserved_flags1:1, + oam_flag:1; +#endif + u8 reserved_flags3; + u8 reserved_flags4; + u8 next_protocol; + __be32 vx_vni; +}; + +/* VXLAN-GPE header flags. */ +#define VXLAN_HF_VER cpu_to_be32(BIT(29) | BIT(28)) +#define VXLAN_HF_NP cpu_to_be32(BIT(26)) +#define VXLAN_HF_OAM cpu_to_be32(BIT(24)) + +#define VXLAN_GPE_USED_BITS (VXLAN_HF_VER | VXLAN_HF_NP | VXLAN_HF_OAM | \ + cpu_to_be32(0xff)) + +struct vxlan_metadata { + u32 gbp; +}; + +/* per UDP socket information */ +struct vxlan_sock { + struct hlist_node hlist; + struct socket *sock; + struct hlist_head vni_list[VNI_HASH_SIZE]; + refcount_t refcnt; + u32 flags; +}; + +union vxlan_addr { + struct sockaddr_in sin; + struct sockaddr_in6 sin6; + struct sockaddr sa; +}; + +struct vxlan_rdst { + union vxlan_addr remote_ip; + __be16 remote_port; + __be32 remote_vni; + u32 remote_ifindex; + struct list_head list; + struct rcu_head rcu; + struct dst_cache dst_cache; +}; + +struct vxlan_config { + union vxlan_addr remote_ip; + union vxlan_addr saddr; + __be32 vni; + int remote_ifindex; + int mtu; + __be16 dst_port; + u16 port_min; + u16 port_max; + u8 tos; + u8 ttl; + __be32 label; + u32 flags; + unsigned long age_interval; + unsigned int addrmax; + bool no_share; +}; + +struct vxlan_dev_node { + struct hlist_node hlist; + struct vxlan_dev *vxlan; +}; + +/* Pseudo network device */ +struct vxlan_dev { + struct vxlan_dev_node hlist4; /* vni hash table for IPv4 socket */ +#if IS_ENABLED(CONFIG_IPV6) + struct vxlan_dev_node hlist6; /* vni hash table for IPv6 socket */ +#endif + struct list_head next; /* vxlan's per namespace list */ + struct vxlan_sock __rcu *vn4_sock; /* listening socket for IPv4 */ +#if IS_ENABLED(CONFIG_IPV6) + struct vxlan_sock __rcu *vn6_sock; /* listening socket for IPv6 */ +#endif + struct net_device *dev; + struct net *net; /* netns for packet i/o */ + struct vxlan_rdst default_dst; /* default destination */ + + struct timer_list age_timer; + spinlock_t hash_lock; + unsigned int addrcnt; + struct gro_cells gro_cells; + + struct vxlan_config cfg; + + struct hlist_head fdb_head[FDB_HASH_SIZE]; +}; + +#define VXLAN_F_LEARN 0x01 +#define VXLAN_F_PROXY 0x02 +#define VXLAN_F_RSC 0x04 +#define VXLAN_F_L2MISS 0x08 +#define VXLAN_F_L3MISS 0x10 +#define VXLAN_F_IPV6 0x20 +#define VXLAN_F_UDP_ZERO_CSUM_TX 0x40 +#define VXLAN_F_UDP_ZERO_CSUM6_TX 0x80 +#define VXLAN_F_UDP_ZERO_CSUM6_RX 0x100 +#define VXLAN_F_REMCSUM_TX 0x200 +#define VXLAN_F_REMCSUM_RX 0x400 +#define VXLAN_F_GBP 0x800 +#define VXLAN_F_REMCSUM_NOPARTIAL 0x1000 +#define VXLAN_F_COLLECT_METADATA 0x2000 +#define VXLAN_F_GPE 0x4000 +#define VXLAN_F_IPV6_LINKLOCAL 0x8000 +#define VXLAN_F_TTL_INHERIT 0x10000 + +/* Flags that are used in the receive path. These flags must match in + * order for a socket to be shareable + */ +#define VXLAN_F_RCV_FLAGS (VXLAN_F_GBP | \ + VXLAN_F_GPE | \ + VXLAN_F_UDP_ZERO_CSUM6_RX | \ + VXLAN_F_REMCSUM_RX | \ + VXLAN_F_REMCSUM_NOPARTIAL | \ + VXLAN_F_COLLECT_METADATA) + +/* Flags that can be set together with VXLAN_F_GPE. */ +#define VXLAN_F_ALLOWED_GPE (VXLAN_F_GPE | \ + VXLAN_F_IPV6 | \ + VXLAN_F_IPV6_LINKLOCAL | \ + VXLAN_F_UDP_ZERO_CSUM_TX | \ + VXLAN_F_UDP_ZERO_CSUM6_TX | \ + VXLAN_F_UDP_ZERO_CSUM6_RX | \ + VXLAN_F_COLLECT_METADATA) + +struct net_device *vxlan_dev_create(struct net *net, const char *name, + u8 name_assign_type, struct vxlan_config *conf); + +static inline netdev_features_t vxlan_features_check(struct sk_buff *skb, + netdev_features_t features) +{ + u8 l4_hdr = 0; + + if (!skb->encapsulation) + return features; + + switch (vlan_get_protocol(skb)) { + case htons(ETH_P_IP): + l4_hdr = ip_hdr(skb)->protocol; + break; + case htons(ETH_P_IPV6): + l4_hdr = ipv6_hdr(skb)->nexthdr; + break; + default: + return features; + } + + if ((l4_hdr == IPPROTO_UDP) && + (skb->inner_protocol_type != ENCAP_TYPE_ETHER || + skb->inner_protocol != htons(ETH_P_TEB) || + (skb_inner_mac_header(skb) - skb_transport_header(skb) != + sizeof(struct udphdr) + sizeof(struct vxlanhdr)) || + (skb->ip_summed != CHECKSUM_NONE && + !can_checksum_protocol(features, inner_eth_hdr(skb)->h_proto)))) + return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); + + return features; +} + +/* IP header + UDP + VXLAN + Ethernet header */ +#define VXLAN_HEADROOM (20 + 8 + 8 + 14) +/* IPv6 header + UDP + VXLAN + Ethernet header */ +#define VXLAN6_HEADROOM (40 + 8 + 8 + 14) + +static inline struct vxlanhdr *vxlan_hdr(struct sk_buff *skb) +{ + return (struct vxlanhdr *)(udp_hdr(skb) + 1); +} + +static inline __be32 vxlan_vni(__be32 vni_field) +{ +#if defined(__BIG_ENDIAN) + return (__force __be32)((__force u32)vni_field >> 8); +#else + return (__force __be32)((__force u32)(vni_field & VXLAN_VNI_MASK) << 8); +#endif +} + +static inline __be32 vxlan_vni_field(__be32 vni) +{ +#if defined(__BIG_ENDIAN) + return (__force __be32)((__force u32)vni << 8); +#else + return (__force __be32)((__force u32)vni >> 8); +#endif +} + +static inline size_t vxlan_rco_start(__be32 vni_field) +{ + return be32_to_cpu(vni_field & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT; +} + +static inline size_t vxlan_rco_offset(__be32 vni_field) +{ + return (vni_field & VXLAN_RCO_UDP) ? + offsetof(struct udphdr, check) : + offsetof(struct tcphdr, check); +} + +static inline __be32 vxlan_compute_rco(unsigned int start, unsigned int offset) +{ + __be32 vni_field = cpu_to_be32(start >> VXLAN_RCO_SHIFT); + + if (offset == offsetof(struct udphdr, check)) + vni_field |= VXLAN_RCO_UDP; + return vni_field; +} + +static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs) +{ + return vs->sock->sk->sk_family; +} + +#endif |