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
13struct 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
40int udp_sock_create4(struct net *net, struct udp_port_cfg *cfg,
41 struct socket **sockp);
42
43#if IS_ENABLED(CONFIG_IPV6)
44int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg,
45 struct socket **sockp);
46#else
47static 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
54static 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
67typedef int (*udp_tunnel_encap_rcv_t)(struct sock *sk, struct sk_buff *skb);
68typedef int (*udp_tunnel_encap_err_lookup_t)(struct sock *sk,
69 struct sk_buff *skb);
70typedef void (*udp_tunnel_encap_destroy_t)(struct sock *sk);
71typedef struct sk_buff *(*udp_tunnel_gro_receive_t)(struct sock *sk,
72 struct list_head *head,
73 struct sk_buff *skb);
74typedef int (*udp_tunnel_gro_complete_t)(struct sock *sk, struct sk_buff *skb,
75 int nhoff);
76
77struct 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 */
89void 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 */
108enum 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
114struct 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 */
122void udp_tunnel_push_rx_port(struct net_device *dev, struct socket *sock,
123 unsigned short type);
124void udp_tunnel_drop_rx_port(struct net_device *dev, struct socket *sock,
125 unsigned short type);
126void udp_tunnel_notify_add_rx_port(struct socket *sock, unsigned short type);
127void udp_tunnel_notify_del_rx_port(struct socket *sock, unsigned short type);
128
129static inline void udp_tunnel_get_rx_info(struct net_device *dev)
130{
131 ASSERT_RTNL();
132 if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
133 return;
134 call_netdevice_notifiers(NETDEV_UDP_TUNNEL_PUSH_INFO, dev);
135}
136
137static inline void udp_tunnel_drop_rx_info(struct net_device *dev)
138{
139 ASSERT_RTNL();
140 if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
141 return;
142 call_netdevice_notifiers(NETDEV_UDP_TUNNEL_DROP_INFO, dev);
143}
144
145/* Transmit the skb using UDP encapsulation. */
146void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
147 __be32 src, __be32 dst, __u8 tos, __u8 ttl,
148 __be16 df, __be16 src_port, __be16 dst_port,
149 bool xnet, bool nocheck);
150
151int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
152 struct sk_buff *skb,
153 struct net_device *dev, struct in6_addr *saddr,
154 struct in6_addr *daddr,
155 __u8 prio, __u8 ttl, __be32 label,
156 __be16 src_port, __be16 dst_port, bool nocheck);
157
158void udp_tunnel_sock_release(struct socket *sock);
159
160struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb, unsigned short family,
161 __be16 flags, __be64 tunnel_id,
162 int md_size);
163
164#ifdef CONFIG_INET
165static inline int udp_tunnel_handle_offloads(struct sk_buff *skb, bool udp_csum)
166{
167 int type = udp_csum ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL;
168
169 return iptunnel_handle_offloads(skb, type);
170}
171#endif
172
173static inline void udp_tunnel_encap_enable(struct socket *sock)
174{
175 struct udp_sock *up = udp_sk(sock->sk);
176
177 if (up->encap_enabled)
178 return;
179
180 up->encap_enabled = 1;
181#if IS_ENABLED(CONFIG_IPV6)
182 if (sock->sk->sk_family == PF_INET6)
183 ipv6_stub->udpv6_encap_enable();
184#endif
185 udp_encap_enable();
186}
187
188#define UDP_TUNNEL_NIC_MAX_TABLES 4
189
190enum udp_tunnel_nic_info_flags {
191 /* Device callbacks may sleep */
192 UDP_TUNNEL_NIC_INFO_MAY_SLEEP = BIT(0),
193 /* Device only supports offloads when it's open, all ports
194 * will be removed before close and re-added after open.
195 */
196 UDP_TUNNEL_NIC_INFO_OPEN_ONLY = BIT(1),
197 /* Device supports only IPv4 tunnels */
198 UDP_TUNNEL_NIC_INFO_IPV4_ONLY = BIT(2),
199 /* Device has hard-coded the IANA VXLAN port (4789) as VXLAN.
200 * This port must not be counted towards n_entries of any table.
201 * Driver will not receive any callback associated with port 4789.
202 */
203 UDP_TUNNEL_NIC_INFO_STATIC_IANA_VXLAN = BIT(3),
204};
205
206struct udp_tunnel_nic;
207
208#define UDP_TUNNEL_NIC_MAX_SHARING_DEVICES (U16_MAX / 2)
209
210struct udp_tunnel_nic_shared {
211 struct udp_tunnel_nic *udp_tunnel_nic_info;
212
213 struct list_head devices;
214};
215
216struct udp_tunnel_nic_shared_node {
217 struct net_device *dev;
218 struct list_head list;
219};
220
221/**
222 * struct udp_tunnel_nic_info - driver UDP tunnel offload information
223 * @set_port: callback for adding a new port
224 * @unset_port: callback for removing a port
225 * @sync_table: callback for syncing the entire port table at once
226 * @shared: reference to device global state (optional)
227 * @flags: device flags from enum udp_tunnel_nic_info_flags
228 * @tables: UDP port tables this device has
229 * @tables.n_entries: number of entries in this table
230 * @tables.tunnel_types: types of tunnels this table accepts
231 *
232 * Drivers are expected to provide either @set_port and @unset_port callbacks
233 * or the @sync_table callback. Callbacks are invoked with rtnl lock held.
234 *
235 * Devices which (misguidedly) share the UDP tunnel port table across multiple
236 * netdevs should allocate an instance of struct udp_tunnel_nic_shared and
237 * point @shared at it.
238 * There must never be more than %UDP_TUNNEL_NIC_MAX_SHARING_DEVICES devices
239 * sharing a table.
240 *
241 * Known limitations:
242 * - UDP tunnel port notifications are fundamentally best-effort -
243 * it is likely the driver will both see skbs which use a UDP tunnel port,
244 * while not being a tunneled skb, and tunnel skbs from other ports -
245 * drivers should only use these ports for non-critical RX-side offloads,
246 * e.g. the checksum offload;
247 * - none of the devices care about the socket family at present, so we don't
248 * track it. Please extend this code if you care.
249 */
250struct udp_tunnel_nic_info {
251 /* one-by-one */
252 int (*set_port)(struct net_device *dev,
253 unsigned int table, unsigned int entry,
254 struct udp_tunnel_info *ti);
255 int (*unset_port)(struct net_device *dev,
256 unsigned int table, unsigned int entry,
257 struct udp_tunnel_info *ti);
258
259 /* all at once */
260 int (*sync_table)(struct net_device *dev, unsigned int table);
261
262 struct udp_tunnel_nic_shared *shared;
263
264 unsigned int flags;
265
266 struct udp_tunnel_nic_table_info {
267 unsigned int n_entries;
268 unsigned int tunnel_types;
269 } tables[UDP_TUNNEL_NIC_MAX_TABLES];
270};
271
272/* UDP tunnel module dependencies
273 *
274 * Tunnel drivers are expected to have a hard dependency on the udp_tunnel
275 * module. NIC drivers are not, they just attach their
276 * struct udp_tunnel_nic_info to the netdev and wait for callbacks to come.
277 * Loading a tunnel driver will cause the udp_tunnel module to be loaded
278 * and only then will all the required state structures be allocated.
279 * Since we want a weak dependency from the drivers and the core to udp_tunnel
280 * we call things through the following stubs.
281 */
282struct udp_tunnel_nic_ops {
283 void (*get_port)(struct net_device *dev, unsigned int table,
284 unsigned int idx, struct udp_tunnel_info *ti);
285 void (*set_port_priv)(struct net_device *dev, unsigned int table,
286 unsigned int idx, u8 priv);
287 void (*add_port)(struct net_device *dev, struct udp_tunnel_info *ti);
288 void (*del_port)(struct net_device *dev, struct udp_tunnel_info *ti);
289 void (*reset_ntf)(struct net_device *dev);
290
291 size_t (*dump_size)(struct net_device *dev, unsigned int table);
292 int (*dump_write)(struct net_device *dev, unsigned int table,
293 struct sk_buff *skb);
294};
295
296#ifdef CONFIG_INET
297extern const struct udp_tunnel_nic_ops *udp_tunnel_nic_ops;
298#else
299#define udp_tunnel_nic_ops ((struct udp_tunnel_nic_ops *)NULL)
300#endif
301
302static inline void
303udp_tunnel_nic_get_port(struct net_device *dev, unsigned int table,
304 unsigned int idx, struct udp_tunnel_info *ti)
305{
306 /* This helper is used from .sync_table, we indicate empty entries
307 * by zero'ed @ti. Drivers which need to know the details of a port
308 * when it gets deleted should use the .set_port / .unset_port
309 * callbacks.
310 * Zero out here, otherwise !CONFIG_INET causes uninitilized warnings.
311 */
312 memset(ti, 0, sizeof(*ti));
313
314 if (udp_tunnel_nic_ops)
315 udp_tunnel_nic_ops->get_port(dev, table, idx, ti);
316}
317
318static inline void
319udp_tunnel_nic_set_port_priv(struct net_device *dev, unsigned int table,
320 unsigned int idx, u8 priv)
321{
322 if (udp_tunnel_nic_ops)
323 udp_tunnel_nic_ops->set_port_priv(dev, table, idx, priv);
324}
325
326static inline void
327udp_tunnel_nic_add_port(struct net_device *dev, struct udp_tunnel_info *ti)
328{
329 if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
330 return;
331 if (udp_tunnel_nic_ops)
332 udp_tunnel_nic_ops->add_port(dev, ti);
333}
334
335static inline void
336udp_tunnel_nic_del_port(struct net_device *dev, struct udp_tunnel_info *ti)
337{
338 if (!(dev->features & NETIF_F_RX_UDP_TUNNEL_PORT))
339 return;
340 if (udp_tunnel_nic_ops)
341 udp_tunnel_nic_ops->del_port(dev, ti);
342}
343
344/**
345 * udp_tunnel_nic_reset_ntf() - device-originating reset notification
346 * @dev: network interface device structure
347 *
348 * Called by the driver to inform the core that the entire UDP tunnel port
349 * state has been lost, usually due to device reset. Core will assume device
350 * forgot all the ports and issue .set_port and .sync_table callbacks as
351 * necessary.
352 *
353 * This function must be called with rtnl lock held, and will issue all
354 * the callbacks before returning.
355 */
356static inline void udp_tunnel_nic_reset_ntf(struct net_device *dev)
357{
358 if (udp_tunnel_nic_ops)
359 udp_tunnel_nic_ops->reset_ntf(dev);
360}
361
362static inline size_t
363udp_tunnel_nic_dump_size(struct net_device *dev, unsigned int table)
364{
365 if (!udp_tunnel_nic_ops)
366 return 0;
367 return udp_tunnel_nic_ops->dump_size(dev, table);
368}
369
370static inline int
371udp_tunnel_nic_dump_write(struct net_device *dev, unsigned int table,
372 struct sk_buff *skb)
373{
374 if (!udp_tunnel_nic_ops)
375 return 0;
376 return udp_tunnel_nic_ops->dump_write(dev, table, skb);
377}
378#endif
379

source code of linux/include/net/udp_tunnel.h