1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __NET_UDP_TUNNEL_H
3 #define __NET_UDP_TUNNEL_H
4
5 #include <net/ip_tunnels.h>
6 #include <net/udp.h>
7
8 #if IS_ENABLED(CONFIG_IPV6)
9 #include <net/ipv6.h>
10 #include <net/ipv6_stubs.h>
11 #endif
12
13 struct udp_port_cfg {
14 u8 family;
15
16 /* Used only for kernel-created sockets */
17 union {
18 struct in_addr local_ip;
19 #if IS_ENABLED(CONFIG_IPV6)
20 struct in6_addr local_ip6;
21 #endif
22 };
23
24 union {
25 struct in_addr peer_ip;
26 #if IS_ENABLED(CONFIG_IPV6)
27 struct in6_addr peer_ip6;
28 #endif
29 };
30
31 __be16 local_udp_port;
32 __be16 peer_udp_port;
33 int bind_ifindex;
34 unsigned int use_udp_checksums:1,
35 use_udp6_tx_checksums:1,
36 use_udp6_rx_checksums:1,
37 ipv6_v6only:1;
38 };
39
40 int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg,
41 struct socket **sockp);
42
43 #if IS_ENABLED(CONFIG_IPV6)
44 int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg,
45 struct socket **sockp);
46 #else
udp_sock_create6(struct net * net,struct udp_port_cfg * cfg,struct socket ** sockp)47 static inline int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg,
48 struct socket **sockp)
49 {
50 return 0;
51 }
52 #endif
53
udp_sock_create(struct net * net,struct udp_port_cfg * cfg,struct socket ** sockp)54 static inline int udp_sock_create(struct net *net,
55 struct udp_port_cfg *cfg,
56 struct socket **sockp)
57 {
58 if (cfg->family == AF_INET)
59 return udp_sock_create4(net, cfg, sockp);
60
61 if (cfg->family == AF_INET6)
62 return udp_sock_create6(net, cfg, sockp);
63
64 return -EPFNOSUPPORT;
65 }
66
67 typedef int (*udp_tunnel_encap_rcv_t)(struct sock *sk, struct sk_buff *skb);
68 typedef int (*udp_tunnel_encap_err_lookup_t)(struct sock *sk,
69 struct sk_buff *skb);
70 typedef void (*udp_tunnel_encap_destroy_t)(struct sock *sk);
71 typedef struct sk_buff *(*udp_tunnel_gro_receive_t)(struct sock *sk,
72 struct list_head *head,
73 struct sk_buff *skb);
74 typedef int (*udp_tunnel_gro_complete_t)(struct sock *sk, struct sk_buff *skb,
75 int nhoff);
76
77 struct udp_tunnel_sock_cfg {
78 void *sk_user_data; /* user data used by encap_rcv call back */
79 /* Used for setting up udp_sock fields, see udp.h for details */
80 __u8 encap_type;
81 udp_tunnel_encap_rcv_t encap_rcv;
82 udp_tunnel_encap_err_lookup_t encap_err_lookup;
83 udp_tunnel_encap_destroy_t encap_destroy;
84 udp_tunnel_gro_receive_t gro_receive;
85 udp_tunnel_gro_complete_t gro_complete;
86 };
87
88 /* Setup the given (UDP) sock to receive UDP encapsulated packets */
89 void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
90 struct udp_tunnel_sock_cfg *sock_cfg);
91
92 /* -- List of parsable UDP tunnel types --
93 *
94 * Adding to this list will result in serious debate. The main issue is
95 * that this list is essentially a list of workarounds for either poorly
96 * designed tunnels, or poorly designed device offloads.
97 *
98 * The parsing supported via these types should really be used for Rx
99 * traffic only as the network stack will have already inserted offsets for
100 * the location of the headers in the skb. In addition any ports that are
101 * pushed should be kept within the namespace without leaking to other
102 * devices such as VFs or other ports on the same device.
103 *
104 * It is strongly encouraged to use CHECKSUM_COMPLETE for Rx to avoid the
105 * need to use this for Rx checksum offload. It should not be necessary to
106 * call this function to perform Tx offloads on outgoing traffic.
107 */
108 enum udp_parsable_tunnel_type {
109 UDP_TUNNEL_TYPE_VXLAN = BIT(0), /* RFC 7348 */
110 UDP_TUNNEL_TYPE_GENEVE = BIT(1), /* draft-ietf-nvo3-geneve */
111 UDP_TUNNEL_TYPE_VXLAN_GPE = BIT(2), /* draft-ietf-nvo3-vxlan-gpe */
112 };
113
114 struct udp_tunnel_info {
115 unsigned short type;
116 sa_family_t sa_family;
117 __be16 port;
118 u8 hw_priv;
119 };
120
121 /* Notify network devices of offloadable types */
122 void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock,
123 unsigned short type);
124 void udp_tunnel_drop_rx_port(struct net_device *dev, struct socket *sock,
125 unsigned short type);
126 void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type);
127 void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type);
128
udp_tunnel_get_rx_info(struct net_device * dev)129 static inline void udp_tunnel_get_rx_info(struct net_device *dev)
130 {
131 ASSERT_RTNL();
132 call_netdevice_notifiers(NETDEV_UDP_TUNNEL_PUSH_INFO, dev);
133 }
134
udp_tunnel_drop_rx_info(struct net_device * dev)135 static inline void udp_tunnel_drop_rx_info(struct net_device *dev)
136 {
137 ASSERT_RTNL();
138 call_netdevice_notifiers(NETDEV_UDP_TUNNEL_DROP_INFO, dev);
139 }
140
141 /* Transmit the skb using UDP encapsulation. */
142 void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
143 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
144 __be16 df, __be16 src_port, __be16 dst_port,
145 bool xnet, bool nocheck);
146
147 int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
148 struct sk_buff *skb,
149 struct net_device *dev, struct in6_addr *saddr,
150 struct in6_addr *daddr,
151 __u8 prio, __u8 ttl, __be32 label,
152 __be16 src_port, __be16 dst_port, bool nocheck);
153
154 void udp_tunnel_sock_release(struct socket *sock);
155
156 struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb, unsigned short family,
157 __be16 flags, __be64 tunnel_id,
158 int md_size);
159
160 #ifdef CONFIG_INET
udp_tunnel_handle_offloads(struct sk_buff * skb,bool udp_csum)161 static inline int udp_tunnel_handle_offloads(struct sk_buff *skb, bool udp_csum)
162 {
163 int type = udp_csum ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL;
164
165 return iptunnel_handle_offloads(skb, type);
166 }
167 #endif
168
udp_tunnel_encap_enable(struct socket * sock)169 static inline void udp_tunnel_encap_enable(struct socket *sock)
170 {
171 struct udp_sock *up = udp_sk(sock->sk);
172
173 if (up->encap_enabled)
174 return;
175
176 up->encap_enabled = 1;
177 #if IS_ENABLED(CONFIG_IPV6)
178 if (sock->sk->sk_family == PF_INET6)
179 ipv6_stub->udpv6_encap_enable();
180 #endif
181 udp_encap_enable();
182 }
183
184 #define UDP_TUNNEL_NIC_MAX_TABLES 4
185
186 enum udp_tunnel_nic_info_flags {
187 /* Device callbacks may sleep */
188 UDP_TUNNEL_NIC_INFO_MAY_SLEEP = BIT(0),
189 /* Device only supports offloads when it's open, all ports
190 * will be removed before close and re-added after open.
191 */
192 UDP_TUNNEL_NIC_INFO_OPEN_ONLY = BIT(1),
193 /* Device supports only IPv4 tunnels */
194 UDP_TUNNEL_NIC_INFO_IPV4_ONLY = BIT(2),
195 /* Device has hard-coded the IANA VXLAN port (4789) as VXLAN.
196 * This port must not be counted towards n_entries of any table.
197 * Driver will not receive any callback associated with port 4789.
198 */
199 UDP_TUNNEL_NIC_INFO_STATIC_IANA_VXLAN = BIT(3),
200 };
201
202 struct udp_tunnel_nic;
203
204 #define UDP_TUNNEL_NIC_MAX_SHARING_DEVICES (U16_MAX / 2)
205
206 struct udp_tunnel_nic_shared {
207 struct udp_tunnel_nic *udp_tunnel_nic_info;
208
209 struct list_head devices;
210 };
211
212 struct udp_tunnel_nic_shared_node {
213 struct net_device *dev;
214 struct list_head list;
215 };
216
217 /**
218 * struct udp_tunnel_nic_info - driver UDP tunnel offload information
219 * @set_port: callback for adding a new port
220 * @unset_port: callback for removing a port
221 * @sync_table: callback for syncing the entire port table at once
222 * @shared: reference to device global state (optional)
223 * @flags: device flags from enum udp_tunnel_nic_info_flags
224 * @tables: UDP port tables this device has
225 * @tables.n_entries: number of entries in this table
226 * @tables.tunnel_types: types of tunnels this table accepts
227 *
228 * Drivers are expected to provide either @set_port and @unset_port callbacks
229 * or the @sync_table callback. Callbacks are invoked with rtnl lock held.
230 *
231 * Devices which (misguidedly) share the UDP tunnel port table across multiple
232 * netdevs should allocate an instance of struct udp_tunnel_nic_shared and
233 * point @shared at it.
234 * There must never be more than %UDP_TUNNEL_NIC_MAX_SHARING_DEVICES devices
235 * sharing a table.
236 *
237 * Known limitations:
238 * - UDP tunnel port notifications are fundamentally best-effort -
239 * it is likely the driver will both see skbs which use a UDP tunnel port,
240 * while not being a tunneled skb, and tunnel skbs from other ports -
241 * drivers should only use these ports for non-critical RX-side offloads,
242 * e.g. the checksum offload;
243 * - none of the devices care about the socket family at present, so we don't
244 * track it. Please extend this code if you care.
245 */
246 struct udp_tunnel_nic_info {
247 /* one-by-one */
248 int (*set_port)(struct net_device *dev,
249 unsigned int table, unsigned int entry,
250 struct udp_tunnel_info *ti);
251 int (*unset_port)(struct net_device *dev,
252 unsigned int table, unsigned int entry,
253 struct udp_tunnel_info *ti);
254
255 /* all at once */
256 int (*sync_table)(struct net_device *dev, unsigned int table);
257
258 struct udp_tunnel_nic_shared *shared;
259
260 unsigned int flags;
261
262 struct udp_tunnel_nic_table_info {
263 unsigned int n_entries;
264 unsigned int tunnel_types;
265 } tables[UDP_TUNNEL_NIC_MAX_TABLES];
266 };
267
268 /* UDP tunnel module dependencies
269 *
270 * Tunnel drivers are expected to have a hard dependency on the udp_tunnel
271 * module. NIC drivers are not, they just attach their
272 * struct udp_tunnel_nic_info to the netdev and wait for callbacks to come.
273 * Loading a tunnel driver will cause the udp_tunnel module to be loaded
274 * and only then will all the required state structures be allocated.
275 * Since we want a weak dependency from the drivers and the core to udp_tunnel
276 * we call things through the following stubs.
277 */
278 struct udp_tunnel_nic_ops {
279 void (*get_port)(struct net_device *dev, unsigned int table,
280 unsigned int idx, struct udp_tunnel_info *ti);
281 void (*set_port_priv)(struct net_device *dev, unsigned int table,
282 unsigned int idx, u8 priv);
283 void (*add_port)(struct net_device *dev, struct udp_tunnel_info *ti);
284 void (*del_port)(struct net_device *dev, struct udp_tunnel_info *ti);
285 void (*reset_ntf)(struct net_device *dev);
286
287 size_t (*dump_size)(struct net_device *dev, unsigned int table);
288 int (*dump_write)(struct net_device *dev, unsigned int table,
289 struct sk_buff *skb);
290 };
291
292 #ifdef CONFIG_INET
293 extern const struct udp_tunnel_nic_ops *udp_tunnel_nic_ops;
294 #else
295 #define udp_tunnel_nic_ops ((struct udp_tunnel_nic_ops *)NULL)
296 #endif
297
298 static inline void
udp_tunnel_nic_get_port(struct net_device * dev,unsigned int table,unsigned int idx,struct udp_tunnel_info * ti)299 udp_tunnel_nic_get_port(struct net_device *dev, unsigned int table,
300 unsigned int idx, struct udp_tunnel_info *ti)
301 {
302 /* This helper is used from .sync_table, we indicate empty entries
303 * by zero'ed @ti. Drivers which need to know the details of a port
304 * when it gets deleted should use the .set_port / .unset_port
305 * callbacks.
306 * Zero out here, otherwise !CONFIG_INET causes uninitilized warnings.
307 */
308 memset(ti, 0, sizeof(*ti));
309
310 if (udp_tunnel_nic_ops)
311 udp_tunnel_nic_ops->get_port(dev, table, idx, ti);
312 }
313
314 static inline void
udp_tunnel_nic_set_port_priv(struct net_device * dev,unsigned int table,unsigned int idx,u8 priv)315 udp_tunnel_nic_set_port_priv(struct net_device *dev, unsigned int table,
316 unsigned int idx, u8 priv)
317 {
318 if (udp_tunnel_nic_ops)
319 udp_tunnel_nic_ops->set_port_priv(dev, table, idx, priv);
320 }
321
322 static inline void
udp_tunnel_nic_add_port(struct net_device * dev,struct udp_tunnel_info * ti)323 udp_tunnel_nic_add_port(struct net_device *dev, struct udp_tunnel_info *ti)
324 {
325 if (udp_tunnel_nic_ops)
326 udp_tunnel_nic_ops->add_port(dev, ti);
327 }
328
329 static inline void
udp_tunnel_nic_del_port(struct net_device * dev,struct udp_tunnel_info * ti)330 udp_tunnel_nic_del_port(struct net_device *dev, struct udp_tunnel_info *ti)
331 {
332 if (udp_tunnel_nic_ops)
333 udp_tunnel_nic_ops->del_port(dev, ti);
334 }
335
336 /**
337 * udp_tunnel_nic_reset_ntf() - device-originating reset notification
338 * @dev: network interface device structure
339 *
340 * Called by the driver to inform the core that the entire UDP tunnel port
341 * state has been lost, usually due to device reset. Core will assume device
342 * forgot all the ports and issue .set_port and .sync_table callbacks as
343 * necessary.
344 *
345 * This function must be called with rtnl lock held, and will issue all
346 * the callbacks before returning.
347 */
udp_tunnel_nic_reset_ntf(struct net_device * dev)348 static inline void udp_tunnel_nic_reset_ntf(struct net_device *dev)
349 {
350 if (udp_tunnel_nic_ops)
351 udp_tunnel_nic_ops->reset_ntf(dev);
352 }
353
354 static inline size_t
udp_tunnel_nic_dump_size(struct net_device * dev,unsigned int table)355 udp_tunnel_nic_dump_size(struct net_device *dev, unsigned int table)
356 {
357 if (!udp_tunnel_nic_ops)
358 return 0;
359 return udp_tunnel_nic_ops->dump_size(dev, table);
360 }
361
362 static inline int
udp_tunnel_nic_dump_write(struct net_device * dev,unsigned int table,struct sk_buff * skb)363 udp_tunnel_nic_dump_write(struct net_device *dev, unsigned int table,
364 struct sk_buff *skb)
365 {
366 if (!udp_tunnel_nic_ops)
367 return 0;
368 return udp_tunnel_nic_ops->dump_write(dev, table, skb);
369 }
370 #endif
371