xref: /openbmc/linux/net/ipv4/udp_tunnel_core.c (revision d9679d00)
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 
10 int 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 
50 error:
51 	if (sock) {
52 		kernel_sock_shutdown(sock, SHUT_RDWR);
53 		sock_release(sock);
54 	}
55 	*sockp = NULL;
56 	return err;
57 }
58 EXPORT_SYMBOL(udp_sock_create4);
59 
60 void 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_lookup = cfg->encap_err_lookup;
76 	udp_sk(sk)->encap_destroy = cfg->encap_destroy;
77 	udp_sk(sk)->gro_receive = cfg->gro_receive;
78 	udp_sk(sk)->gro_complete = cfg->gro_complete;
79 
80 	udp_tunnel_encap_enable(sock);
81 }
82 EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
83 
84 void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock,
85 			     unsigned short type)
86 {
87 	struct sock *sk = sock->sk;
88 	struct udp_tunnel_info ti;
89 
90 	ti.type = type;
91 	ti.sa_family = sk->sk_family;
92 	ti.port = inet_sk(sk)->inet_sport;
93 
94 	udp_tunnel_nic_add_port(dev, &ti);
95 }
96 EXPORT_SYMBOL_GPL(udp_tunnel_push_rx_port);
97 
98 void udp_tunnel_drop_rx_port(struct net_device *dev, struct socket *sock,
99 			     unsigned short type)
100 {
101 	struct sock *sk = sock->sk;
102 	struct udp_tunnel_info ti;
103 
104 	ti.type = type;
105 	ti.sa_family = sk->sk_family;
106 	ti.port = inet_sk(sk)->inet_sport;
107 
108 	udp_tunnel_nic_del_port(dev, &ti);
109 }
110 EXPORT_SYMBOL_GPL(udp_tunnel_drop_rx_port);
111 
112 /* Notify netdevs that UDP port started listening */
113 void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type)
114 {
115 	struct sock *sk = sock->sk;
116 	struct net *net = sock_net(sk);
117 	struct udp_tunnel_info ti;
118 	struct net_device *dev;
119 
120 	ti.type = type;
121 	ti.sa_family = sk->sk_family;
122 	ti.port = inet_sk(sk)->inet_sport;
123 
124 	rcu_read_lock();
125 	for_each_netdev_rcu(net, dev) {
126 		udp_tunnel_nic_add_port(dev, &ti);
127 	}
128 	rcu_read_unlock();
129 }
130 EXPORT_SYMBOL_GPL(udp_tunnel_notify_add_rx_port);
131 
132 /* Notify netdevs that UDP port is no more listening */
133 void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type)
134 {
135 	struct sock *sk = sock->sk;
136 	struct net *net = sock_net(sk);
137 	struct udp_tunnel_info ti;
138 	struct net_device *dev;
139 
140 	ti.type = type;
141 	ti.sa_family = sk->sk_family;
142 	ti.port = inet_sk(sk)->inet_sport;
143 
144 	rcu_read_lock();
145 	for_each_netdev_rcu(net, dev) {
146 		udp_tunnel_nic_del_port(dev, &ti);
147 	}
148 	rcu_read_unlock();
149 }
150 EXPORT_SYMBOL_GPL(udp_tunnel_notify_del_rx_port);
151 
152 void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
153 			 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
154 			 __be16 df, __be16 src_port, __be16 dst_port,
155 			 bool xnet, bool nocheck)
156 {
157 	struct udphdr *uh;
158 
159 	__skb_push(skb, sizeof(*uh));
160 	skb_reset_transport_header(skb);
161 	uh = udp_hdr(skb);
162 
163 	uh->dest = dst_port;
164 	uh->source = src_port;
165 	uh->len = htons(skb->len);
166 
167 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
168 
169 	udp_set_csum(nocheck, skb, src, dst, skb->len);
170 
171 	iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet);
172 }
173 EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
174 
175 void udp_tunnel_sock_release(struct socket *sock)
176 {
177 	rcu_assign_sk_user_data(sock->sk, NULL);
178 	kernel_sock_shutdown(sock, SHUT_RDWR);
179 	sock_release(sock);
180 }
181 EXPORT_SYMBOL_GPL(udp_tunnel_sock_release);
182 
183 struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb,  unsigned short family,
184 				    __be16 flags, __be64 tunnel_id, int md_size)
185 {
186 	struct metadata_dst *tun_dst;
187 	struct ip_tunnel_info *info;
188 
189 	if (family == AF_INET)
190 		tun_dst = ip_tun_rx_dst(skb, flags, tunnel_id, md_size);
191 	else
192 		tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id, md_size);
193 	if (!tun_dst)
194 		return NULL;
195 
196 	info = &tun_dst->u.tun_info;
197 	info->key.tp_src = udp_hdr(skb)->source;
198 	info->key.tp_dst = udp_hdr(skb)->dest;
199 	if (udp_hdr(skb)->check)
200 		info->key.tun_flags |= TUNNEL_CSUM;
201 	return tun_dst;
202 }
203 EXPORT_SYMBOL_GPL(udp_tun_rx_dst);
204 
205 MODULE_LICENSE("GPL");
206