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 = kernel_setsockopt(sock, SOL_SOCKET, SO_BINDTOIFINDEX,
 26					(void *)&cfg->bind_ifindex,
 27					sizeof(cfg->bind_ifindex));
 28		if (err < 0)
 29			goto error;
 30	}
 31
 32	udp_addr.sin_family = AF_INET;
 33	udp_addr.sin_addr = cfg->local_ip;
 34	udp_addr.sin_port = cfg->local_udp_port;
 35	err = kernel_bind(sock, (struct sockaddr *)&udp_addr,
 36			  sizeof(udp_addr));
 37	if (err < 0)
 38		goto error;
 39
 40	if (cfg->peer_udp_port) {
 41		udp_addr.sin_family = AF_INET;
 42		udp_addr.sin_addr = cfg->peer_ip;
 43		udp_addr.sin_port = cfg->peer_udp_port;
 44		err = kernel_connect(sock, (struct sockaddr *)&udp_addr,
 45				     sizeof(udp_addr), 0);
 46		if (err < 0)
 47			goto error;
 48	}
 49
 50	sock->sk->sk_no_check_tx = !cfg->use_udp_checksums;
 51
 52	*sockp = sock;
 53	return 0;
 54
 55error:
 56	if (sock) {
 57		kernel_sock_shutdown(sock, SHUT_RDWR);
 58		sock_release(sock);
 59	}
 60	*sockp = NULL;
 61	return err;
 62}
 63EXPORT_SYMBOL(udp_sock_create4);
 64
 65void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
 66			   struct udp_tunnel_sock_cfg *cfg)
 67{
 68	struct sock *sk = sock->sk;
 69
 70	/* Disable multicast loopback */
 71	inet_sk(sk)->mc_loop = 0;
 72
 73	/* Enable CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion */
 74	inet_inc_convert_csum(sk);
 75
 76	rcu_assign_sk_user_data(sk, cfg->sk_user_data);
 77
 78	udp_sk(sk)->encap_type = cfg->encap_type;
 79	udp_sk(sk)->encap_rcv = cfg->encap_rcv;
 80	udp_sk(sk)->encap_err_lookup = cfg->encap_err_lookup;
 81	udp_sk(sk)->encap_destroy = cfg->encap_destroy;
 82	udp_sk(sk)->gro_receive = cfg->gro_receive;
 83	udp_sk(sk)->gro_complete = cfg->gro_complete;
 84
 85	udp_tunnel_encap_enable(sock);
 86}
 87EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
 88
 89void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock,
 90			     unsigned short type)
 91{
 92	struct sock *sk = sock->sk;
 93	struct udp_tunnel_info ti;
 94
 95	if (!dev->netdev_ops->ndo_udp_tunnel_add ||
 96	    !(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
 97		return;
 98
 99	ti.type = type;
100	ti.sa_family = sk->sk_family;
101	ti.port = inet_sk(sk)->inet_sport;
102
103	dev->netdev_ops->ndo_udp_tunnel_add(dev, &ti);
104}
105EXPORT_SYMBOL_GPL(udp_tunnel_push_rx_port);
106
107void udp_tunnel_drop_rx_port(struct net_device *dev, struct socket *sock,
108			     unsigned short type)
109{
110	struct sock *sk = sock->sk;
111	struct udp_tunnel_info ti;
112
113	if (!dev->netdev_ops->ndo_udp_tunnel_del ||
114	    !(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
115		return;
116
117	ti.type = type;
118	ti.sa_family = sk->sk_family;
119	ti.port = inet_sk(sk)->inet_sport;
120
121	dev->netdev_ops->ndo_udp_tunnel_del(dev, &ti);
122}
123EXPORT_SYMBOL_GPL(udp_tunnel_drop_rx_port);
124
125/* Notify netdevs that UDP port started listening */
126void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type)
127{
128	struct sock *sk = sock->sk;
129	struct net *net = sock_net(sk);
130	struct udp_tunnel_info ti;
131	struct net_device *dev;
132
133	ti.type = type;
134	ti.sa_family = sk->sk_family;
135	ti.port = inet_sk(sk)->inet_sport;
136
137	rcu_read_lock();
138	for_each_netdev_rcu(net, dev) {
139		if (!dev->netdev_ops->ndo_udp_tunnel_add)
140			continue;
141		if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
142			continue;
143		dev->netdev_ops->ndo_udp_tunnel_add(dev, &ti);
144	}
145	rcu_read_unlock();
146}
147EXPORT_SYMBOL_GPL(udp_tunnel_notify_add_rx_port);
148
149/* Notify netdevs that UDP port is no more listening */
150void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type)
151{
152	struct sock *sk = sock->sk;
153	struct net *net = sock_net(sk);
154	struct udp_tunnel_info ti;
155	struct net_device *dev;
156
157	ti.type = type;
158	ti.sa_family = sk->sk_family;
159	ti.port = inet_sk(sk)->inet_sport;
160
161	rcu_read_lock();
162	for_each_netdev_rcu(net, dev) {
163		if (!dev->netdev_ops->ndo_udp_tunnel_del)
164			continue;
165		if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
166			continue;
167		dev->netdev_ops->ndo_udp_tunnel_del(dev, &ti);
168	}
169	rcu_read_unlock();
170}
171EXPORT_SYMBOL_GPL(udp_tunnel_notify_del_rx_port);
172
173void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
174			 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
175			 __be16 df, __be16 src_port, __be16 dst_port,
176			 bool xnet, bool nocheck)
177{
178	struct udphdr *uh;
179
180	__skb_push(skb, sizeof(*uh));
181	skb_reset_transport_header(skb);
182	uh = udp_hdr(skb);
183
184	uh->dest = dst_port;
185	uh->source = src_port;
186	uh->len = htons(skb->len);
187
188	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
189
190	udp_set_csum(nocheck, skb, src, dst, skb->len);
191
192	iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet);
193}
194EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
195
196void udp_tunnel_sock_release(struct socket *sock)
197{
198	rcu_assign_sk_user_data(sock->sk, NULL);
199	kernel_sock_shutdown(sock, SHUT_RDWR);
200	sock_release(sock);
201}
202EXPORT_SYMBOL_GPL(udp_tunnel_sock_release);
203
204struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb,  unsigned short family,
205				    __be16 flags, __be64 tunnel_id, int md_size)
206{
207	struct metadata_dst *tun_dst;
208	struct ip_tunnel_info *info;
209
210	if (family == AF_INET)
211		tun_dst = ip_tun_rx_dst(skb, flags, tunnel_id, md_size);
212	else
213		tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id, md_size);
214	if (!tun_dst)
215		return NULL;
216
217	info = &tun_dst->u.tun_info;
218	info->key.tp_src = udp_hdr(skb)->source;
219	info->key.tp_dst = udp_hdr(skb)->dest;
220	if (udp_hdr(skb)->check)
221		info->key.tun_flags |= TUNNEL_CSUM;
222	return tun_dst;
223}
224EXPORT_SYMBOL_GPL(udp_tun_rx_dst);
225
226MODULE_LICENSE("GPL");