1 files changed, 108 insertions, 0 deletions
diff --git a/net/ipv4/udp_tunnel.c b/net/ipv4/udp_tunnel.c
new file mode 100644
index 000000000..6bb98cc19
--- /dev/null
+++ b/net/ipv4/udp_tunnel.c
@@ -0,0 +1,108 @@
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/socket.h>
+#include <linux/udp.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <net/udp.h>
+#include <net/udp_tunnel.h>
+#include <net/net_namespace.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(AF_INET, SOCK_DGRAM, 0, &sock);
+	if (err < 0)
+		goto error;
+
+	sk_change_net(sock->sk, net);
+
+	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 *)&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 *)&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);
+		sk_release_kernel(sock->sk);
+	}
+	*sockp = NULL;
+	return err;
+}
+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 */
+	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_destroy = cfg->encap_destroy;
+
+	udp_tunnel_encap_enable(sock);
+}
+EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
+
+int 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)
+{
+	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(nocheck, skb, src, dst, skb->len);
+
+	return iptunnel_xmit(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");