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/flow.h>
8 #include <net/udp.h>
9 #include <net/udp_tunnel.h>
10 #include <net/inet_dscp.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 if (cfg->bind_ifindex) {
24 err = sock_bindtoindex(sock->sk, cfg->bind_ifindex, true);
25 if (err < 0)
26 goto error;
27 }
28
29 udp_addr.sin_family = AF_INET;
30 udp_addr.sin_addr = cfg->local_ip;
31 udp_addr.sin_port = cfg->local_udp_port;
32 err = kernel_bind(sock, (struct sockaddr_unsized *)&udp_addr,
33 sizeof(udp_addr));
34 if (err < 0)
35 goto error;
36
37 if (cfg->peer_udp_port) {
38 udp_addr.sin_family = AF_INET;
39 udp_addr.sin_addr = cfg->peer_ip;
40 udp_addr.sin_port = cfg->peer_udp_port;
41 err = kernel_connect(sock, (struct sockaddr_unsized *)&udp_addr,
42 sizeof(udp_addr), 0);
43 if (err < 0)
44 goto error;
45 }
46
47 sock->sk->sk_no_check_tx = !cfg->use_udp_checksums;
48
49 *sockp = sock;
50 return 0;
51
52 error:
53 if (sock) {
54 kernel_sock_shutdown(sock, SHUT_RDWR);
55 sock_release(sock);
56 }
57 *sockp = NULL;
58 return err;
59 }
60 EXPORT_SYMBOL(udp_sock_create4);
61
sk_saddr_any(struct sock * sk)62 static bool sk_saddr_any(struct sock *sk)
63 {
64 #if IS_ENABLED(CONFIG_IPV6)
65 return ipv6_addr_any(&sk->sk_v6_rcv_saddr);
66 #else
67 return !sk->sk_rcv_saddr;
68 #endif
69 }
70
setup_udp_tunnel_sock(struct net * net,struct sock * sk,struct udp_tunnel_sock_cfg * cfg)71 void setup_udp_tunnel_sock(struct net *net, struct sock *sk,
72 struct udp_tunnel_sock_cfg *cfg)
73 {
74 /* Disable multicast loopback */
75 inet_clear_bit(MC_LOOP, sk);
76
77 /* Enable CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE conversion */
78 inet_inc_convert_csum(sk);
79
80 rcu_assign_sk_user_data(sk, cfg->sk_user_data);
81
82 udp_sk(sk)->encap_type = cfg->encap_type;
83 udp_sk(sk)->encap_rcv = cfg->encap_rcv;
84 udp_sk(sk)->encap_err_rcv = cfg->encap_err_rcv;
85 udp_sk(sk)->encap_err_lookup = cfg->encap_err_lookup;
86 udp_sk(sk)->encap_destroy = cfg->encap_destroy;
87 udp_sk(sk)->gro_receive = cfg->gro_receive;
88 udp_sk(sk)->gro_complete = cfg->gro_complete;
89
90 udp_tunnel_encap_enable(sk);
91
92 udp_tunnel_update_gro_rcv(sk, true);
93
94 if (!sk->sk_dport && !sk->sk_bound_dev_if && sk_saddr_any(sk) &&
95 sk->sk_kern_sock)
96 udp_tunnel_update_gro_lookup(net, sk, true);
97 }
98 EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
99
udp_tunnel_push_rx_port(struct net_device * dev,struct sock * sk,unsigned short type)100 void udp_tunnel_push_rx_port(struct net_device *dev, struct sock *sk,
101 unsigned short type)
102 {
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_add_port(dev, &ti);
110 }
111 EXPORT_SYMBOL_GPL(udp_tunnel_push_rx_port);
112
udp_tunnel_drop_rx_port(struct net_device * dev,struct sock * sk,unsigned short type)113 void udp_tunnel_drop_rx_port(struct net_device *dev, struct sock *sk,
114 unsigned short type)
115 {
116 struct udp_tunnel_info ti;
117
118 ti.type = type;
119 ti.sa_family = sk->sk_family;
120 ti.port = inet_sk(sk)->inet_sport;
121
122 udp_tunnel_nic_del_port(dev, &ti);
123 }
124 EXPORT_SYMBOL_GPL(udp_tunnel_drop_rx_port);
125
126 /* Notify netdevs that UDP port started listening */
udp_tunnel_notify_add_rx_port(struct sock * sk,unsigned short type)127 void udp_tunnel_notify_add_rx_port(struct sock *sk, unsigned short type)
128 {
129 struct net *net = sock_net(sk);
130 struct udp_tunnel_info ti;
131 struct net_device *dev;
132
133 ASSERT_RTNL();
134
135 ti.type = type;
136 ti.sa_family = sk->sk_family;
137 ti.port = inet_sk(sk)->inet_sport;
138
139 for_each_netdev(net, dev) {
140 udp_tunnel_nic_lock(dev);
141 udp_tunnel_nic_add_port(dev, &ti);
142 udp_tunnel_nic_unlock(dev);
143 }
144 }
145 EXPORT_SYMBOL_GPL(udp_tunnel_notify_add_rx_port);
146
147 /* Notify netdevs that UDP port is no more listening */
udp_tunnel_notify_del_rx_port(struct sock * sk,unsigned short type)148 void udp_tunnel_notify_del_rx_port(struct sock *sk, unsigned short type)
149 {
150 struct net *net = sock_net(sk);
151 struct udp_tunnel_info ti;
152 struct net_device *dev;
153
154 ASSERT_RTNL();
155
156 ti.type = type;
157 ti.sa_family = sk->sk_family;
158 ti.port = inet_sk(sk)->inet_sport;
159
160 for_each_netdev(net, dev) {
161 udp_tunnel_nic_lock(dev);
162 udp_tunnel_nic_del_port(dev, &ti);
163 udp_tunnel_nic_unlock(dev);
164 }
165 }
166 EXPORT_SYMBOL_GPL(udp_tunnel_notify_del_rx_port);
167
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,u16 ipcb_flags)168 void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
169 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
170 __be16 df, __be16 src_port, __be16 dst_port,
171 bool xnet, bool nocheck, u16 ipcb_flags)
172 {
173 struct udphdr *uh;
174
175 __skb_push(skb, sizeof(*uh));
176 skb_reset_transport_header(skb);
177 uh = udp_hdr(skb);
178
179 uh->dest = dst_port;
180 uh->source = src_port;
181 udp_set_len(uh, skb->len);
182
183 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
184
185 udp_set_csum(nocheck, skb, src, dst, skb->len);
186
187 iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet,
188 ipcb_flags);
189 }
190 EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
191
udp_tunnel_sock_release(struct sock * sk)192 void udp_tunnel_sock_release(struct sock *sk)
193 {
194 struct socket *sock = sk->sk_socket;
195
196 rcu_assign_sk_user_data(sk, NULL);
197 kernel_sock_shutdown(sock, SHUT_RDWR);
198 sock_release(sock);
199 }
200 EXPORT_SYMBOL_GPL(udp_tunnel_sock_release);
201
udp_tun_rx_dst(struct sk_buff * skb,unsigned short family,const unsigned long * flags,__be64 tunnel_id,int md_size)202 struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb, unsigned short family,
203 const unsigned long *flags,
204 __be64 tunnel_id, int md_size)
205 {
206 struct metadata_dst *tun_dst;
207 struct ip_tunnel_info *info;
208
209 if (family == AF_INET)
210 tun_dst = ip_tun_rx_dst(skb, flags, tunnel_id, md_size);
211 else
212 tun_dst = ipv6_tun_rx_dst(skb, flags, tunnel_id, md_size);
213 if (!tun_dst)
214 return NULL;
215
216 info = &tun_dst->u.tun_info;
217 info->key.tp_src = udp_hdr(skb)->source;
218 info->key.tp_dst = udp_hdr(skb)->dest;
219 if (udp_hdr(skb)->check)
220 __set_bit(IP_TUNNEL_CSUM_BIT, info->key.tun_flags);
221 return tun_dst;
222 }
223 EXPORT_SYMBOL_GPL(udp_tun_rx_dst);
224
udp_tunnel_dst_lookup(struct sk_buff * skb,struct net_device * dev,struct net * net,int oif,__be32 * saddr,const struct ip_tunnel_key * key,__be16 sport,__be16 dport,u8 tos,struct dst_cache * dst_cache)225 struct rtable *udp_tunnel_dst_lookup(struct sk_buff *skb,
226 struct net_device *dev,
227 struct net *net, int oif,
228 __be32 *saddr,
229 const struct ip_tunnel_key *key,
230 __be16 sport, __be16 dport, u8 tos,
231 struct dst_cache *dst_cache)
232 {
233 struct rtable *rt = NULL;
234 struct flowi4 fl4;
235
236 #ifdef CONFIG_DST_CACHE
237 if (dst_cache) {
238 rt = dst_cache_get_ip4(dst_cache, saddr);
239 if (rt)
240 return rt;
241 }
242 #endif
243
244 memset(&fl4, 0, sizeof(fl4));
245 fl4.flowi4_mark = skb->mark;
246 fl4.flowi4_proto = IPPROTO_UDP;
247 fl4.flowi4_oif = oif;
248 fl4.daddr = key->u.ipv4.dst;
249 fl4.saddr = key->u.ipv4.src;
250 fl4.fl4_dport = dport;
251 fl4.fl4_sport = sport;
252 fl4.flowi4_dscp = inet_dsfield_to_dscp(tos);
253 fl4.flowi4_flags = key->flow_flags;
254
255 rt = ip_route_output_key(net, &fl4);
256 if (IS_ERR(rt)) {
257 netdev_dbg(dev, "no route to %pI4\n", &fl4.daddr);
258 return ERR_PTR(-ENETUNREACH);
259 }
260 if (rt->dst.dev == dev) { /* is this necessary? */
261 netdev_dbg(dev, "circular route to %pI4\n", &fl4.daddr);
262 ip_rt_put(rt);
263 return ERR_PTR(-ELOOP);
264 }
265 #ifdef CONFIG_DST_CACHE
266 if (dst_cache)
267 dst_cache_set_ip4(dst_cache, &rt->dst, fl4.saddr);
268 #endif
269 *saddr = fl4.saddr;
270 return rt;
271 }
272 EXPORT_SYMBOL_GPL(udp_tunnel_dst_lookup);
273
274 MODULE_DESCRIPTION("IPv4 Foo over UDP tunnel driver");
275 MODULE_LICENSE("GPL");
276