1// SPDX-License-Identifier: GPL-2.0-only
  2#include <linux/module.h>
  3#include <linux/errno.h>
  4#include <linux/socket.h>
  5#include <linux/kernel.h>
  6#include <net/dst_metadata.h>
  7#include <net/udp.h>
  8#include <net/udp_tunnel.h>
  9
 10int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg,
 11		     struct socket **sockp)
 12{
 13	int err;
 14	struct socket *sock = NULL;
 15	struct sockaddr_in udp_addr;
 16
 17	err = sock_create_kern(net, AF_INET, SOCK_DGRAM, 0, &sock);
 18	if (err < 0)
 19		goto error;
 20
 21	if (cfg->bind_ifindex) {
 22		err = sock_bindtoindex(sock->sk, cfg->bind_ifindex, true);
 23		if (err < 0)
 24			goto error;
 25	}
 26
 27	udp_addr.sin_family = AF_INET;
 28	udp_addr.sin_addr = cfg->local_ip;
 29	udp_addr.sin_port = cfg->local_udp_port;
 30	err = kernel_bind(sock, (struct sockaddr *)&udp_addr,
 31			  sizeof(udp_addr));
 32	if (err < 0)
 33		goto error;
 34
 35	if (cfg->peer_udp_port) {
 36		udp_addr.sin_family = AF_INET;
 37		udp_addr.sin_addr = cfg->peer_ip;
 38		udp_addr.sin_port = cfg->peer_udp_port;
 39		err = kernel_connect(sock, (struct sockaddr *)&udp_addr,
 40				     sizeof(udp_addr), 0);
 41		if (err < 0)
 42			goto error;
 43	}
 44
 45	sock->sk->sk_no_check_tx = !cfg->use_udp_checksums;
 46
 47	*sockp = sock;
 48	return 0;
 49
 50error:
 51	if (sock) {
 52		kernel_sock_shutdown(sock, SHUT_RDWR);
 53		sock_release(sock);
 54	}
 55	*sockp = NULL;
 56	return err;
 57}
 58EXPORT_SYMBOL(udp_sock_create4);
 59
 60void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
 61			   struct udp_tunnel_sock_cfg *cfg)
 62{
 63	struct sock *sk = sock->sk;
 64
 65	/* Disable multicast loopback */
 66	inet_sk(sk)->mc_loop = 0;
 67
 68	/* Enable CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion */
 69	inet_inc_convert_csum(sk);
 70
 71	rcu_assign_sk_user_data(sk, cfg->sk_user_data);
 72
 73	udp_sk(sk)->encap_type = cfg->encap_type;
 74	udp_sk(sk)->encap_rcv = cfg->encap_rcv;
 75	udp_sk(sk)->encap_err_rcv = cfg->encap_err_rcv;
 76	udp_sk(sk)->encap_err_lookup = cfg->encap_err_lookup;
 77	udp_sk(sk)->encap_destroy = cfg->encap_destroy;
 78	udp_sk(sk)->gro_receive = cfg->gro_receive;
 79	udp_sk(sk)->gro_complete = cfg->gro_complete;
 80
 81	udp_tunnel_encap_enable(sock);
 82}
 83EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
 84
 85void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock,
 86			     unsigned short type)
 87{
 88	struct sock *sk = sock->sk;
 89	struct udp_tunnel_info ti;
 90
 91	ti.type = type;
 92	ti.sa_family = sk->sk_family;
 93	ti.port = inet_sk(sk)->inet_sport;
 94
 95	udp_tunnel_nic_add_port(dev, &ti);
 96}
 97EXPORT_SYMBOL_GPL(udp_tunnel_push_rx_port);
 98
 99void udp_tunnel_drop_rx_port(struct net_device *dev, struct socket *sock,
100			     unsigned short type)
101{
102	struct sock *sk = sock->sk;
103	struct udp_tunnel_info ti;
104
105	ti.type = type;
106	ti.sa_family = sk->sk_family;
107	ti.port = inet_sk(sk)->inet_sport;
108
109	udp_tunnel_nic_del_port(dev, &ti);
110}
111EXPORT_SYMBOL_GPL(udp_tunnel_drop_rx_port);
112
113/* Notify netdevs that UDP port started listening */
114void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type)
115{
116	struct sock *sk = sock->sk;
117	struct net *net = sock_net(sk);
118	struct udp_tunnel_info ti;
119	struct net_device *dev;
120
121	ti.type = type;
122	ti.sa_family = sk->sk_family;
123	ti.port = inet_sk(sk)->inet_sport;
124
125	rcu_read_lock();
126	for_each_netdev_rcu(net, dev) {
127		udp_tunnel_nic_add_port(dev, &ti);
128	}
129	rcu_read_unlock();
130}
131EXPORT_SYMBOL_GPL(udp_tunnel_notify_add_rx_port);
132
133/* Notify netdevs that UDP port is no more listening */
134void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type)
135{
136	struct sock *sk = sock->sk;
137	struct net *net = sock_net(sk);
138	struct udp_tunnel_info ti;
139	struct net_device *dev;
140
141	ti.type = type;
142	ti.sa_family = sk->sk_family;
143	ti.port = inet_sk(sk)->inet_sport;
144
145	rcu_read_lock();
146	for_each_netdev_rcu(net, dev) {
147		udp_tunnel_nic_del_port(dev, &ti);
148	}
149	rcu_read_unlock();
150}
151EXPORT_SYMBOL_GPL(udp_tunnel_notify_del_rx_port);
152
153void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
154			 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
155			 __be16 df, __be16 src_port, __be16 dst_port,
156			 bool xnet, bool nocheck)
157{
158	struct udphdr *uh;
159
160	__skb_push(skb, sizeof(*uh));
161	skb_reset_transport_header(skb);
162	uh = udp_hdr(skb);
163
164	uh->dest = dst_port;
165	uh->source = src_port;
166	uh->len = htons(skb->len);
167
168	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
169
170	udp_set_csum(nocheck, skb, src, dst, skb->len);
171
172	iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet);
173}
174EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
175
176void udp_tunnel_sock_release(struct socket *sock)
177{
178	rcu_assign_sk_user_data(sock->sk, NULL);
179	synchronize_rcu();
180	kernel_sock_shutdown(sock, SHUT_RDWR);
181	sock_release(sock);
182}
183EXPORT_SYMBOL_GPL(udp_tunnel_sock_release);
184
185struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb,  unsigned short family,
186				    __be16 flags, __be64 tunnel_id, int md_size)
187{
188	struct metadata_dst *tun_dst;
189	struct ip_tunnel_info *info;
190
191	if (family == AF_INET)
192		tun_dst = ip_tun_rx_dst(skb, flags, tunnel_id, md_size);
193	else
194		tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id, md_size);
195	if (!tun_dst)
196		return NULL;
197
198	info = &tun_dst->u.tun_info;
199	info->key.tp_src = udp_hdr(skb)->source;
200	info->key.tp_dst = udp_hdr(skb)->dest;
201	if (udp_hdr(skb)->check)
202		info->key.tun_flags |= TUNNEL_CSUM;
203	return tun_dst;
204}
205EXPORT_SYMBOL_GPL(udp_tun_rx_dst);
206
207MODULE_LICENSE("GPL");