1#include <linux/module.h>
  2#include <linux/errno.h>
  3#include <linux/socket.h>
  4#include <linux/udp.h>
  5#include <linux/types.h>
  6#include <linux/kernel.h>
  7#include <net/dst_metadata.h>
  8#include <net/net_namespace.h>
  9#include <net/udp.h>
 10#include <net/udp_tunnel.h>
 11
 12int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg,
 13		     struct socket **sockp)
 14{
 15	int err;
 16	struct socket *sock = NULL;
 17	struct sockaddr_in udp_addr;
 18
 19	err = sock_create_kern(net, AF_INET, SOCK_DGRAM, 0, &sock);
 20	if (err < 0)
 21		goto error;
 22
 23	udp_addr.sin_family = AF_INET;
 24	udp_addr.sin_addr = cfg->local_ip;
 25	udp_addr.sin_port = cfg->local_udp_port;
 26	err = kernel_bind(sock, (struct sockaddr *)&udp_addr,
 27			  sizeof(udp_addr));
 28	if (err < 0)
 29		goto error;
 30
 31	if (cfg->peer_udp_port) {
 32		udp_addr.sin_family = AF_INET;
 33		udp_addr.sin_addr = cfg->peer_ip;
 34		udp_addr.sin_port = cfg->peer_udp_port;
 35		err = kernel_connect(sock, (struct sockaddr *)&udp_addr,
 36				     sizeof(udp_addr), 0);
 37		if (err < 0)
 38			goto error;
 39	}
 40
 41	sock->sk->sk_no_check_tx = !cfg->use_udp_checksums;
 42
 43	*sockp = sock;
 44	return 0;
 45
 46error:
 47	if (sock) {
 48		kernel_sock_shutdown(sock, SHUT_RDWR);
 49		sock_release(sock);
 50	}
 51	*sockp = NULL;
 52	return err;
 53}
 54EXPORT_SYMBOL(udp_sock_create4);
 55
 56void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
 57			   struct udp_tunnel_sock_cfg *cfg)
 58{
 59	struct sock *sk = sock->sk;
 60
 61	/* Disable multicast loopback */
 62	inet_sk(sk)->mc_loop = 0;
 63
 64	/* Enable CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion */
 65	inet_inc_convert_csum(sk);
 66
 67	rcu_assign_sk_user_data(sk, cfg->sk_user_data);
 68
 69	udp_sk(sk)->encap_type = cfg->encap_type;
 70	udp_sk(sk)->encap_rcv = cfg->encap_rcv;
 71	udp_sk(sk)->encap_destroy = cfg->encap_destroy;
 72	udp_sk(sk)->gro_receive = cfg->gro_receive;
 73	udp_sk(sk)->gro_complete = cfg->gro_complete;
 74
 75	udp_tunnel_encap_enable(sock);
 76}
 77EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
 78
 79void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock,
 80			     unsigned short type)
 81{
 82	struct sock *sk = sock->sk;
 83	struct udp_tunnel_info ti;
 84
 85	if (!dev->netdev_ops->ndo_udp_tunnel_add)
 86		return;
 87
 88	ti.type = type;
 89	ti.sa_family = sk->sk_family;
 90	ti.port = inet_sk(sk)->inet_sport;
 91
 92	dev->netdev_ops->ndo_udp_tunnel_add(dev, &ti);
 93}
 94EXPORT_SYMBOL_GPL(udp_tunnel_push_rx_port);
 95
 96/* Notify netdevs that UDP port started listening */
 97void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type)
 98{
 99	struct sock *sk = sock->sk;
100	struct net *net = sock_net(sk);
101	struct udp_tunnel_info ti;
102	struct net_device *dev;
103
104	ti.type = type;
105	ti.sa_family = sk->sk_family;
106	ti.port = inet_sk(sk)->inet_sport;
107
108	rcu_read_lock();
109	for_each_netdev_rcu(net, dev) {
110		if (!dev->netdev_ops->ndo_udp_tunnel_add)
111			continue;
112		dev->netdev_ops->ndo_udp_tunnel_add(dev, &ti);
113	}
114	rcu_read_unlock();
115}
116EXPORT_SYMBOL_GPL(udp_tunnel_notify_add_rx_port);
117
118/* Notify netdevs that UDP port is no more listening */
119void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type)
120{
121	struct sock *sk = sock->sk;
122	struct net *net = sock_net(sk);
123	struct udp_tunnel_info ti;
124	struct net_device *dev;
125
126	ti.type = type;
127	ti.sa_family = sk->sk_family;
128	ti.port = inet_sk(sk)->inet_sport;
129
130	rcu_read_lock();
131	for_each_netdev_rcu(net, dev) {
132		if (!dev->netdev_ops->ndo_udp_tunnel_del)
133			continue;
134		dev->netdev_ops->ndo_udp_tunnel_del(dev, &ti);
135	}
136	rcu_read_unlock();
137}
138EXPORT_SYMBOL_GPL(udp_tunnel_notify_del_rx_port);
139
140void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
141			 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
142			 __be16 df, __be16 src_port, __be16 dst_port,
143			 bool xnet, bool nocheck)
144{
145	struct udphdr *uh;
146
147	__skb_push(skb, sizeof(*uh));
148	skb_reset_transport_header(skb);
149	uh = udp_hdr(skb);
150
151	uh->dest = dst_port;
152	uh->source = src_port;
153	uh->len = htons(skb->len);
154
155	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
156
157	udp_set_csum(nocheck, skb, src, dst, skb->len);
158
159	iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet);
160}
161EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
162
163void udp_tunnel_sock_release(struct socket *sock)
164{
165	rcu_assign_sk_user_data(sock->sk, NULL);
166	kernel_sock_shutdown(sock, SHUT_RDWR);
167	sock_release(sock);
168}
169EXPORT_SYMBOL_GPL(udp_tunnel_sock_release);
170
171struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb,  unsigned short family,
172				    __be16 flags, __be64 tunnel_id, int md_size)
173{
174	struct metadata_dst *tun_dst;
175	struct ip_tunnel_info *info;
176
177	if (family == AF_INET)
178		tun_dst = ip_tun_rx_dst(skb, flags, tunnel_id, md_size);
179	else
180		tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id, md_size);
181	if (!tun_dst)
182		return NULL;
183
184	info = &tun_dst->u.tun_info;
185	info->key.tp_src = udp_hdr(skb)->source;
186	info->key.tp_dst = udp_hdr(skb)->dest;
187	if (udp_hdr(skb)->check)
188		info->key.tun_flags |= TUNNEL_CSUM;
189	return tun_dst;
190}
191EXPORT_SYMBOL_GPL(udp_tun_rx_dst);
192
193MODULE_LICENSE("GPL");