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/udp.h>
  6#include <linux/types.h>
  7#include <linux/kernel.h>
  8#include <net/dst_metadata.h>
  9#include <net/net_namespace.h>
 10#include <net/udp.h>
 11#include <net/udp_tunnel.h>
 12
 13int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg,
 14		     struct socket **sockp)
 15{
 16	int err;
 17	struct socket *sock = NULL;
 18	struct sockaddr_in udp_addr;
 19
 20	err = sock_create_kern(net, AF_INET, SOCK_DGRAM, 0, &sock);
 21	if (err < 0)
 22		goto error;
 23
 24	if (cfg->bind_ifindex) {
 25		err = sock_bindtoindex(sock->sk, cfg->bind_ifindex, true);
 26		if (err < 0)
 27			goto error;
 28	}
 29
 30	udp_addr.sin_family = AF_INET;
 31	udp_addr.sin_addr = cfg->local_ip;
 32	udp_addr.sin_port = cfg->local_udp_port;
 33	err = kernel_bind(sock, (struct sockaddr *)&udp_addr,
 34			  sizeof(udp_addr));
 35	if (err < 0)
 36		goto error;
 37
 38	if (cfg->peer_udp_port) {
 39		udp_addr.sin_family = AF_INET;
 40		udp_addr.sin_addr = cfg->peer_ip;
 41		udp_addr.sin_port = cfg->peer_udp_port;
 42		err = kernel_connect(sock, (struct sockaddr *)&udp_addr,
 43				     sizeof(udp_addr), 0);
 44		if (err < 0)
 45			goto error;
 46	}
 47
 48	sock->sk->sk_no_check_tx = !cfg->use_udp_checksums;
 49
 50	*sockp = sock;
 51	return 0;
 52
 53error:
 54	if (sock) {
 55		kernel_sock_shutdown(sock, SHUT_RDWR);
 56		sock_release(sock);
 57	}
 58	*sockp = NULL;
 59	return err;
 60}
 61EXPORT_SYMBOL(udp_sock_create4);
 62
 63void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
 64			   struct udp_tunnel_sock_cfg *cfg)
 65{
 66	struct sock *sk = sock->sk;
 67
 68	/* Disable multicast loopback */
 69	inet_sk(sk)->mc_loop = 0;
 70
 71	/* Enable CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion */
 72	inet_inc_convert_csum(sk);
 73
 74	rcu_assign_sk_user_data(sk, cfg->sk_user_data);
 75
 76	udp_sk(sk)->encap_type = cfg->encap_type;
 77	udp_sk(sk)->encap_rcv = cfg->encap_rcv;
 78	udp_sk(sk)->encap_err_lookup = cfg->encap_err_lookup;
 79	udp_sk(sk)->encap_destroy = cfg->encap_destroy;
 80	udp_sk(sk)->gro_receive = cfg->gro_receive;
 81	udp_sk(sk)->gro_complete = cfg->gro_complete;
 82
 83	udp_tunnel_encap_enable(sock);
 84}
 85EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
 86
 87void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock,
 88			     unsigned short type)
 89{
 90	struct sock *sk = sock->sk;
 91	struct udp_tunnel_info ti;
 92
 93	if (!dev->netdev_ops->ndo_udp_tunnel_add ||
 94	    !(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
 95		return;
 96
 97	ti.type = type;
 98	ti.sa_family = sk->sk_family;
 99	ti.port = inet_sk(sk)->inet_sport;
100
101	dev->netdev_ops->ndo_udp_tunnel_add(dev, &ti);
102}
103EXPORT_SYMBOL_GPL(udp_tunnel_push_rx_port);
104
105void udp_tunnel_drop_rx_port(struct net_device *dev, struct socket *sock,
106			     unsigned short type)
107{
108	struct sock *sk = sock->sk;
109	struct udp_tunnel_info ti;
110
111	if (!dev->netdev_ops->ndo_udp_tunnel_del ||
112	    !(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
113		return;
114
115	ti.type = type;
116	ti.sa_family = sk->sk_family;
117	ti.port = inet_sk(sk)->inet_sport;
118
119	dev->netdev_ops->ndo_udp_tunnel_del(dev, &ti);
120}
121EXPORT_SYMBOL_GPL(udp_tunnel_drop_rx_port);
122
123/* Notify netdevs that UDP port started listening */
124void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type)
125{
126	struct sock *sk = sock->sk;
127	struct net *net = sock_net(sk);
128	struct udp_tunnel_info ti;
129	struct net_device *dev;
130
131	ti.type = type;
132	ti.sa_family = sk->sk_family;
133	ti.port = inet_sk(sk)->inet_sport;
134
135	rcu_read_lock();
136	for_each_netdev_rcu(net, dev) {
137		if (!dev->netdev_ops->ndo_udp_tunnel_add)
138			continue;
139		if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
140			continue;
141		dev->netdev_ops->ndo_udp_tunnel_add(dev, &ti);
142	}
143	rcu_read_unlock();
144}
145EXPORT_SYMBOL_GPL(udp_tunnel_notify_add_rx_port);
146
147/* Notify netdevs that UDP port is no more listening */
148void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type)
149{
150	struct sock *sk = sock->sk;
151	struct net *net = sock_net(sk);
152	struct udp_tunnel_info ti;
153	struct net_device *dev;
154
155	ti.type = type;
156	ti.sa_family = sk->sk_family;
157	ti.port = inet_sk(sk)->inet_sport;
158
159	rcu_read_lock();
160	for_each_netdev_rcu(net, dev) {
161		if (!dev->netdev_ops->ndo_udp_tunnel_del)
162			continue;
163		if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
164			continue;
165		dev->netdev_ops->ndo_udp_tunnel_del(dev, &ti);
166	}
167	rcu_read_unlock();
168}
169EXPORT_SYMBOL_GPL(udp_tunnel_notify_del_rx_port);
170
171void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
172			 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
173			 __be16 df, __be16 src_port, __be16 dst_port,
174			 bool xnet, bool nocheck)
175{
176	struct udphdr *uh;
177
178	__skb_push(skb, sizeof(*uh));
179	skb_reset_transport_header(skb);
180	uh = udp_hdr(skb);
181
182	uh->dest = dst_port;
183	uh->source = src_port;
184	uh->len = htons(skb->len);
185
186	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
187
188	udp_set_csum(nocheck, skb, src, dst, skb->len);
189
190	iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet);
191}
192EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
193
194void udp_tunnel_sock_release(struct socket *sock)
195{
196	rcu_assign_sk_user_data(sock->sk, NULL);
197	kernel_sock_shutdown(sock, SHUT_RDWR);
198	sock_release(sock);
199}
200EXPORT_SYMBOL_GPL(udp_tunnel_sock_release);
201
202struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb,  unsigned short family,
203				    __be16 flags, __be64 tunnel_id, int md_size)
204{
205	struct metadata_dst *tun_dst;
206	struct ip_tunnel_info *info;
207
208	if (family == AF_INET)
209		tun_dst = ip_tun_rx_dst(skb, flags, tunnel_id, md_size);
210	else
211		tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id, md_size);
212	if (!tun_dst)
213		return NULL;
214
215	info = &tun_dst->u.tun_info;
216	info->key.tp_src = udp_hdr(skb)->source;
217	info->key.tp_dst = udp_hdr(skb)->dest;
218	if (udp_hdr(skb)->check)
219		info->key.tun_flags |= TUNNEL_CSUM;
220	return tun_dst;
221}
222EXPORT_SYMBOL_GPL(udp_tun_rx_dst);
223
224MODULE_LICENSE("GPL");