From 6a93cc9052748c6355ec9d5b6c38b77f85f1cb0d Mon Sep 17 00:00:00 2001 From: Andy Zhou Date: Tue, 16 Sep 2014 17:31:17 -0700 Subject: [PATCH] udp-tunnel: Add a few more UDP tunnel APIs Added a few more UDP tunnel APIs that can be shared by UDP based tunnel protocol implementation. The main ones are highlighted below. setup_udp_tunnel_sock() configures UDP listener socket for receiving UDP encapsulated packets. udp_tunnel_xmit_skb() and upd_tunnel6_xmit_skb() transmit skb using UDP encapsulation. udp_tunnel_sock_release() closes the UDP tunnel listener socket. Signed-off-by: Andy Zhou Signed-off-by: David S. Miller --- include/net/udp_tunnel.h | 57 +++++++++++++++++++++++++++++++++++++++ net/ipv4/udp_tunnel.c | 53 +++++++++++++++++++++++++++++++++++- net/ipv6/ip6_udp_tunnel.c | 42 +++++++++++++++++++++++++++++ 3 files changed, 151 insertions(+), 1 deletion(-) diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h index 0b9e017c9038..a47790bcaa38 100644 --- a/include/net/udp_tunnel.h +++ b/include/net/udp_tunnel.h @@ -1,6 +1,14 @@ #ifndef __NET_UDP_TUNNEL_H #define __NET_UDP_TUNNEL_H +#include +#include + +#if IS_ENABLED(CONFIG_IPV6) +#include +#include +#endif + struct udp_port_cfg { u8 family; @@ -53,4 +61,53 @@ static inline int udp_sock_create(struct net *net, return -EPFNOSUPPORT; } +typedef int (*udp_tunnel_encap_rcv_t)(struct sock *sk, struct sk_buff *skb); +typedef void (*udp_tunnel_encap_destroy_t)(struct sock *sk); + +struct udp_tunnel_sock_cfg { + void *sk_user_data; /* user data used by encap_rcv call back */ + /* Used for setting up udp_sock fields, see udp.h for details */ + __u8 encap_type; + udp_tunnel_encap_rcv_t encap_rcv; + udp_tunnel_encap_destroy_t encap_destroy; +}; + +/* Setup the given (UDP) sock to receive UDP encapsulated packets */ +void setup_udp_tunnel_sock(struct net *net, struct socket *sock, + struct udp_tunnel_sock_cfg *sock_cfg); + +/* Transmit the skb using UDP encapsulation. */ +int udp_tunnel_xmit_skb(struct socket *sock, struct rtable *rt, + struct sk_buff *skb, __be32 src, __be32 dst, + __u8 tos, __u8 ttl, __be16 df, __be16 src_port, + __be16 dst_port, bool xnet); + +#if IS_ENABLED(CONFIG_IPV6) +int udp_tunnel6_xmit_skb(struct socket *sock, struct dst_entry *dst, + struct sk_buff *skb, struct net_device *dev, + struct in6_addr *saddr, struct in6_addr *daddr, + __u8 prio, __u8 ttl, __be16 src_port, + __be16 dst_port); +#endif + +void udp_tunnel_sock_release(struct socket *sock); + +static inline struct sk_buff *udp_tunnel_handle_offloads(struct sk_buff *skb, + bool udp_csum) +{ + int type = udp_csum ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL; + + return iptunnel_handle_offloads(skb, udp_csum, type); +} + +static inline void udp_tunnel_encap_enable(struct socket *sock) +{ +#if IS_ENABLED(CONFIG_IPV6) + if (sock->sk->sk_family == PF_INET6) + ipv6_stub->udpv6_encap_enable(); + else +#endif + udp_encap_enable(); +} + #endif diff --git a/net/ipv4/udp_tunnel.c b/net/ipv4/udp_tunnel.c index 7fccf6c3417a..1671263e5fa0 100644 --- a/net/ipv4/udp_tunnel.c +++ b/net/ipv4/udp_tunnel.c @@ -11,7 +11,7 @@ int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg, struct socket **sockp) { - int err = -EINVAL; + int err; struct socket *sock = NULL; struct sockaddr_in udp_addr; @@ -54,4 +54,55 @@ int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg, } EXPORT_SYMBOL(udp_sock_create4); +void setup_udp_tunnel_sock(struct net *net, struct socket *sock, + struct udp_tunnel_sock_cfg *cfg) +{ + struct sock *sk = sock->sk; + + /* Disable multicast loopback */ + inet_sk(sk)->mc_loop = 0; + + /* Enable CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion */ + udp_set_convert_csum(sk, true); + + rcu_assign_sk_user_data(sk, cfg->sk_user_data); + + udp_sk(sk)->encap_type = cfg->encap_type; + udp_sk(sk)->encap_rcv = cfg->encap_rcv; + udp_sk(sk)->encap_destroy = cfg->encap_destroy; + + udp_tunnel_encap_enable(sock); +} +EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock); + +int udp_tunnel_xmit_skb(struct socket *sock, struct rtable *rt, + struct sk_buff *skb, __be32 src, __be32 dst, + __u8 tos, __u8 ttl, __be16 df, __be16 src_port, + __be16 dst_port, bool xnet) +{ + struct udphdr *uh; + + __skb_push(skb, sizeof(*uh)); + skb_reset_transport_header(skb); + uh = udp_hdr(skb); + + uh->dest = dst_port; + uh->source = src_port; + uh->len = htons(skb->len); + + udp_set_csum(sock->sk->sk_no_check_tx, skb, src, dst, skb->len); + + return iptunnel_xmit(sock->sk, rt, skb, src, dst, IPPROTO_UDP, + tos, ttl, df, xnet); +} +EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb); + +void udp_tunnel_sock_release(struct socket *sock) +{ + rcu_assign_sk_user_data(sock->sk, NULL); + kernel_sock_shutdown(sock, SHUT_RDWR); + sk_release_kernel(sock->sk); +} +EXPORT_SYMBOL_GPL(udp_tunnel_sock_release); + MODULE_LICENSE("GPL"); diff --git a/net/ipv6/ip6_udp_tunnel.c b/net/ipv6/ip6_udp_tunnel.c index bcfbb4b496fc..cbc990712cc1 100644 --- a/net/ipv6/ip6_udp_tunnel.c +++ b/net/ipv6/ip6_udp_tunnel.c @@ -61,3 +61,45 @@ int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg, return err; } EXPORT_SYMBOL_GPL(udp_sock_create6); + +int udp_tunnel6_xmit_skb(struct socket *sock, struct dst_entry *dst, + struct sk_buff *skb, struct net_device *dev, + struct in6_addr *saddr, struct in6_addr *daddr, + __u8 prio, __u8 ttl, __be16 src_port, __be16 dst_port) +{ + struct udphdr *uh; + struct ipv6hdr *ip6h; + struct sock *sk = sock->sk; + + __skb_push(skb, sizeof(*uh)); + skb_reset_transport_header(skb); + uh = udp_hdr(skb); + + uh->dest = dst_port; + uh->source = src_port; + + uh->len = htons(skb->len); + uh->check = 0; + + memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); + IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED + | IPSKB_REROUTED); + skb_dst_set(skb, dst); + + udp6_set_csum(udp_get_no_check6_tx(sk), skb, &inet6_sk(sk)->saddr, + &sk->sk_v6_daddr, skb->len); + + __skb_push(skb, sizeof(*ip6h)); + skb_reset_network_header(skb); + ip6h = ipv6_hdr(skb); + ip6_flow_hdr(ip6h, prio, htonl(0)); + ip6h->payload_len = htons(skb->len); + ip6h->nexthdr = IPPROTO_UDP; + ip6h->hop_limit = ttl; + ip6h->daddr = *daddr; + ip6h->saddr = *saddr; + + ip6tunnel_xmit(skb, dev); + return 0; +} +EXPORT_SYMBOL_GPL(udp_tunnel6_xmit_skb);