#include <linux/module.h>
#include <linux/errno.h>
#include <linux/socket.h>
#include <linux/kernel.h>
#include <net/dst_metadata.h>
#include <net/flow.h>
#include <net/udp.h>
#include <net/udp_tunnel.h>
#include <net/inet_dscp.h>
int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg,
struct socket **sockp)
{
int err;
struct socket *sock = NULL;
struct sockaddr_in udp_addr;
err = sock_create_kern(net, AF_INET, SOCK_DGRAM, 0, &sock);
if (err < 0)
goto error;
if (cfg->bind_ifindex) {
err = sock_bindtoindex(sock->sk, cfg->bind_ifindex, true);
if (err < 0)
goto error;
}
udp_addr.sin_family = AF_INET;
udp_addr.sin_addr = cfg->local_ip;
udp_addr.sin_port = cfg->local_udp_port;
err = kernel_bind(sock, (struct sockaddr_unsized *)&udp_addr,
sizeof(udp_addr));
if (err < 0)
goto error;
if (cfg->peer_udp_port) {
udp_addr.sin_family = AF_INET;
udp_addr.sin_addr = cfg->peer_ip;
udp_addr.sin_port = cfg->peer_udp_port;
err = kernel_connect(sock, (struct sockaddr_unsized *)&udp_addr,
sizeof(udp_addr), 0);
if (err < 0)
goto error;
}
sock->sk->sk_no_check_tx = !cfg->use_udp_checksums;
*sockp = sock;
return 0;
error:
if (sock) {
kernel_sock_shutdown(sock, SHUT_RDWR);
sock_release(sock);
}
*sockp = NULL;
return err;
}
EXPORT_SYMBOL(udp_sock_create4);
static bool sk_saddr_any(struct sock *sk)
{
#if IS_ENABLED(CONFIG_IPV6)
return ipv6_addr_any(&sk->sk_v6_rcv_saddr);
#else
return !sk->sk_rcv_saddr;
#endif
}
void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
struct udp_tunnel_sock_cfg *cfg)
{
struct sock *sk = sock->sk;
inet_clear_bit(MC_LOOP, sk);
inet_inc_convert_csum(sk);
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_err_rcv = cfg->encap_err_rcv;
udp_sk(sk)->encap_err_lookup = cfg->encap_err_lookup;
udp_sk(sk)->encap_destroy = cfg->encap_destroy;
udp_sk(sk)->gro_receive = cfg->gro_receive;
udp_sk(sk)->gro_complete = cfg->gro_complete;
udp_tunnel_encap_enable(sk);
udp_tunnel_update_gro_rcv(sk, true);
if (!sk->sk_dport && !sk->sk_bound_dev_if && sk_saddr_any(sk) &&
sk->sk_kern_sock)
udp_tunnel_update_gro_lookup(net, sk, true);
}
EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock,
unsigned short type)
{
struct sock *sk = sock->sk;
struct udp_tunnel_info ti;
ti.type = type;
ti.sa_family = sk->sk_family;
ti.port = inet_sk(sk)->inet_sport;
udp_tunnel_nic_add_port(dev, &ti);
}
EXPORT_SYMBOL_GPL(udp_tunnel_push_rx_port);
void udp_tunnel_drop_rx_port(struct net_device *dev, struct socket *sock,
unsigned short type)
{
struct sock *sk = sock->sk;
struct udp_tunnel_info ti;
ti.type = type;
ti.sa_family = sk->sk_family;
ti.port = inet_sk(sk)->inet_sport;
udp_tunnel_nic_del_port(dev, &ti);
}
EXPORT_SYMBOL_GPL(udp_tunnel_drop_rx_port);
void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type)
{
struct sock *sk = sock->sk;
struct net *net = sock_net(sk);
struct udp_tunnel_info ti;
struct net_device *dev;
ASSERT_RTNL();
ti.type = type;
ti.sa_family = sk->sk_family;
ti.port = inet_sk(sk)->inet_sport;
for_each_netdev(net, dev) {
udp_tunnel_nic_lock(dev);
udp_tunnel_nic_add_port(dev, &ti);
udp_tunnel_nic_unlock(dev);
}
}
EXPORT_SYMBOL_GPL(udp_tunnel_notify_add_rx_port);
void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type)
{
struct sock *sk = sock->sk;
struct net *net = sock_net(sk);
struct udp_tunnel_info ti;
struct net_device *dev;
ASSERT_RTNL();
ti.type = type;
ti.sa_family = sk->sk_family;
ti.port = inet_sk(sk)->inet_sport;
for_each_netdev(net, dev) {
udp_tunnel_nic_lock(dev);
udp_tunnel_nic_del_port(dev, &ti);
udp_tunnel_nic_unlock(dev);
}
}
EXPORT_SYMBOL_GPL(udp_tunnel_notify_del_rx_port);
void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
__be32 src, __be32 dst, __u8 tos, __u8 ttl,
__be16 df, __be16 src_port, __be16 dst_port,
bool xnet, bool nocheck, u16 ipcb_flags)
{
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);
memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
udp_set_csum(nocheck, skb, src, dst, skb->len);
iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet,
ipcb_flags);
}
EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
void udp_tunnel_sock_release(struct socket *sock)
{
rcu_assign_sk_user_data(sock->sk, NULL);
synchronize_rcu();
kernel_sock_shutdown(sock, SHUT_RDWR);
sock_release(sock);
}
EXPORT_SYMBOL_GPL(udp_tunnel_sock_release);
struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb, unsigned short family,
const unsigned long *flags,
__be64 tunnel_id, int md_size)
{
struct metadata_dst *tun_dst;
struct ip_tunnel_info *info;
if (family == AF_INET)
tun_dst = ip_tun_rx_dst(skb, flags, tunnel_id, md_size);
else
tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id, md_size);
if (!tun_dst)
return NULL;
info = &tun_dst->u.tun_info;
info->key.tp_src = udp_hdr(skb)->source;
info->key.tp_dst = udp_hdr(skb)->dest;
if (udp_hdr(skb)->check)
__set_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags);
return tun_dst;
}
EXPORT_SYMBOL_GPL(udp_tun_rx_dst);
struct rtable *udp_tunnel_dst_lookup(struct sk_buff *skb,
struct net_device *dev,
struct net *net, int oif,
__be32 *saddr,
const struct ip_tunnel_key *key,
__be16 sport, __be16 dport, u8 tos,
struct dst_cache *dst_cache)
{
struct rtable *rt = NULL;
struct flowi4 fl4;
#ifdef CONFIG_DST_CACHE
if (dst_cache) {
rt = dst_cache_get_ip4(dst_cache, saddr);
if (rt)
return rt;
}
#endif
memset(&fl4, 0, sizeof(fl4));
fl4.flowi4_mark = skb->mark;
fl4.flowi4_proto = IPPROTO_UDP;
fl4.flowi4_oif = oif;
fl4.daddr = key->u.ipv4.dst;
fl4.saddr = key->u.ipv4.src;
fl4.fl4_dport = dport;
fl4.fl4_sport = sport;
fl4.flowi4_dscp = inet_dsfield_to_dscp(tos);
fl4.flowi4_flags = key->flow_flags;
rt = ip_route_output_key(net, &fl4);
if (IS_ERR(rt)) {
netdev_dbg(dev, "no route to %pI4\n", &fl4.daddr);
return ERR_PTR(-ENETUNREACH);
}
if (rt->dst.dev == dev) {
netdev_dbg(dev, "circular route to %pI4\n", &fl4.daddr);
ip_rt_put(rt);
return ERR_PTR(-ELOOP);
}
#ifdef CONFIG_DST_CACHE
if (dst_cache)
dst_cache_set_ip4(dst_cache, &rt->dst, fl4.saddr);
#endif
*saddr = fl4.saddr;
return rt;
}
EXPORT_SYMBOL_GPL(udp_tunnel_dst_lookup);
MODULE_DESCRIPTION("IPv4 Foo over UDP tunnel driver");
MODULE_LICENSE("GPL");
