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, type: SOCK_DGRAM, proto: 0, res: &sock); |
18 | if (err < 0) |
19 | goto error; |
20 | |
21 | if (cfg->bind_ifindex) { |
22 | err = sock_bindtoindex(sk: sock->sk, ifindex: cfg->bind_ifindex, lock_sk: 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, addr: (struct sockaddr *)&udp_addr, |
31 | addrlen: 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, addr: (struct sockaddr *)&udp_addr, |
40 | addrlen: sizeof(udp_addr), flags: 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, how: 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_clear_bit(MC_LOOP, sk); |
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(sk); |
82 | } |
83 | EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock); |
84 | |
85 | void 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: &ti); |
96 | } |
97 | EXPORT_SYMBOL_GPL(udp_tunnel_push_rx_port); |
98 | |
99 | void 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: &ti); |
110 | } |
111 | EXPORT_SYMBOL_GPL(udp_tunnel_drop_rx_port); |
112 | |
113 | /* Notify netdevs that UDP port started listening */ |
114 | void 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: &ti); |
128 | } |
129 | rcu_read_unlock(); |
130 | } |
131 | EXPORT_SYMBOL_GPL(udp_tunnel_notify_add_rx_port); |
132 | |
133 | /* Notify netdevs that UDP port is no more listening */ |
134 | void 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: &ti); |
148 | } |
149 | rcu_read_unlock(); |
150 | } |
151 | EXPORT_SYMBOL_GPL(udp_tunnel_notify_del_rx_port); |
152 | |
153 | void 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, len: 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, saddr: src, daddr: dst, len: skb->len); |
171 | |
172 | iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP, tos, ttl, df, xnet); |
173 | } |
174 | EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb); |
175 | |
176 | void 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, how: SHUT_RDWR); |
181 | sock_release(sock); |
182 | } |
183 | EXPORT_SYMBOL_GPL(udp_tunnel_sock_release); |
184 | |
185 | struct 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 | } |
205 | EXPORT_SYMBOL_GPL(udp_tun_rx_dst); |
206 | |
207 | struct rtable *udp_tunnel_dst_lookup(struct sk_buff *skb, |
208 | struct net_device *dev, |
209 | struct net *net, int oif, |
210 | __be32 *saddr, |
211 | const struct ip_tunnel_key *key, |
212 | __be16 sport, __be16 dport, u8 tos, |
213 | struct dst_cache *dst_cache) |
214 | { |
215 | struct rtable *rt = NULL; |
216 | struct flowi4 fl4; |
217 | |
218 | #ifdef CONFIG_DST_CACHE |
219 | if (dst_cache) { |
220 | rt = dst_cache_get_ip4(dst_cache, saddr); |
221 | if (rt) |
222 | return rt; |
223 | } |
224 | #endif |
225 | |
226 | memset(&fl4, 0, sizeof(fl4)); |
227 | fl4.flowi4_mark = skb->mark; |
228 | fl4.flowi4_proto = IPPROTO_UDP; |
229 | fl4.flowi4_oif = oif; |
230 | fl4.daddr = key->u.ipv4.dst; |
231 | fl4.saddr = key->u.ipv4.src; |
232 | fl4.fl4_dport = dport; |
233 | fl4.fl4_sport = sport; |
234 | fl4.flowi4_tos = RT_TOS(tos); |
235 | fl4.flowi4_flags = key->flow_flags; |
236 | |
237 | rt = ip_route_output_key(net, flp: &fl4); |
238 | if (IS_ERR(ptr: rt)) { |
239 | netdev_dbg(dev, "no route to %pI4\n" , &fl4.daddr); |
240 | return ERR_PTR(error: -ENETUNREACH); |
241 | } |
242 | if (rt->dst.dev == dev) { /* is this necessary? */ |
243 | netdev_dbg(dev, "circular route to %pI4\n" , &fl4.daddr); |
244 | ip_rt_put(rt); |
245 | return ERR_PTR(error: -ELOOP); |
246 | } |
247 | #ifdef CONFIG_DST_CACHE |
248 | if (dst_cache) |
249 | dst_cache_set_ip4(dst_cache, dst: &rt->dst, saddr: fl4.saddr); |
250 | #endif |
251 | *saddr = fl4.saddr; |
252 | return rt; |
253 | } |
254 | EXPORT_SYMBOL_GPL(udp_tunnel_dst_lookup); |
255 | |
256 | MODULE_DESCRIPTION("IPv4 Foo over UDP tunnel driver" ); |
257 | MODULE_LICENSE("GPL" ); |
258 | |