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 
udp_sock_create4(struct net * net,struct udp_port_cfg * cfg,struct socket ** sockp)12 int 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 
46 error:
47 	if (sock) {
48 		kernel_sock_shutdown(sock, SHUT_RDWR);
49 		sock_release(sock);
50 	}
51 	*sockp = NULL;
52 	return err;
53 }
54 EXPORT_SYMBOL(udp_sock_create4);
55 
setup_udp_tunnel_sock(struct net * net,struct socket * sock,struct udp_tunnel_sock_cfg * cfg)56 void 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 
73 	udp_tunnel_encap_enable(sock);
74 }
75 EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
76 
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)77 int udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
78 			__be32 src, __be32 dst, __u8 tos, __u8 ttl,
79 			__be16 df, __be16 src_port, __be16 dst_port,
80 			bool xnet, bool nocheck)
81 {
82 	struct udphdr *uh;
83 
84 	__skb_push(skb, sizeof(*uh));
85 	skb_reset_transport_header(skb);
86 	uh = udp_hdr(skb);
87 
88 	uh->dest = dst_port;
89 	uh->source = src_port;
90 	uh->len = htons(skb->len);
91 
92 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
93 
94 	udp_set_csum(nocheck, skb, src, dst, skb->len);
95 
96 	return iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP,
97 			     tos, ttl, df, xnet);
98 }
99 EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
100 
udp_tunnel_sock_release(struct socket * sock)101 void udp_tunnel_sock_release(struct socket *sock)
102 {
103 	rcu_assign_sk_user_data(sock->sk, NULL);
104 	kernel_sock_shutdown(sock, SHUT_RDWR);
105 	sock_release(sock);
106 }
107 EXPORT_SYMBOL_GPL(udp_tunnel_sock_release);
108 
udp_tun_rx_dst(struct sk_buff * skb,unsigned short family,__be16 flags,__be64 tunnel_id,int md_size)109 struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb,  unsigned short family,
110 				    __be16 flags, __be64 tunnel_id, int md_size)
111 {
112 	struct metadata_dst *tun_dst;
113 	struct ip_tunnel_info *info;
114 
115 	if (family == AF_INET)
116 		tun_dst = ip_tun_rx_dst(skb, flags, tunnel_id, md_size);
117 	else
118 		tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id, md_size);
119 	if (!tun_dst)
120 		return NULL;
121 
122 	info = &tun_dst->u.tun_info;
123 	info->key.tp_src = udp_hdr(skb)->source;
124 	info->key.tp_dst = udp_hdr(skb)->dest;
125 	if (udp_hdr(skb)->check)
126 		info->key.tun_flags |= TUNNEL_CSUM;
127 	return tun_dst;
128 }
129 EXPORT_SYMBOL_GPL(udp_tun_rx_dst);
130 
131 MODULE_LICENSE("GPL");
132