xref: /linux/include/net/af_vsock.h (revision 6e7fd890f1d6ac83805409e9c346240de2705584)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * VMware vSockets Driver
4  *
5  * Copyright (C) 2007-2013 VMware, Inc. All rights reserved.
6  */
7 
8 #ifndef __AF_VSOCK_H__
9 #define __AF_VSOCK_H__
10 
11 #include <linux/kernel.h>
12 #include <linux/workqueue.h>
13 #include <net/sock.h>
14 #include <uapi/linux/vm_sockets.h>
15 
16 #include "vsock_addr.h"
17 
18 #define LAST_RESERVED_PORT 1023
19 
20 #define VSOCK_HASH_SIZE         251
21 extern struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1];
22 extern struct list_head vsock_connected_table[VSOCK_HASH_SIZE];
23 extern spinlock_t vsock_table_lock;
24 
25 #define vsock_sk(__sk)    ((struct vsock_sock *)__sk)
26 #define sk_vsock(__vsk)   (&(__vsk)->sk)
27 
28 struct vsock_sock {
29 	/* sk must be the first member. */
30 	struct sock sk;
31 	const struct vsock_transport *transport;
32 	struct sockaddr_vm local_addr;
33 	struct sockaddr_vm remote_addr;
34 	/* Links for the global tables of bound and connected sockets. */
35 	struct list_head bound_table;
36 	struct list_head connected_table;
37 	/* Accessed without the socket lock held. This means it can never be
38 	 * modified outsided of socket create or destruct.
39 	 */
40 	bool trusted;
41 	bool cached_peer_allow_dgram;	/* Dgram communication allowed to
42 					 * cached peer?
43 					 */
44 	u32 cached_peer;  /* Context ID of last dgram destination check. */
45 	const struct cred *owner;
46 	/* Rest are SOCK_STREAM only. */
47 	long connect_timeout;
48 	/* Listening socket that this came from. */
49 	struct sock *listener;
50 	/* Used for pending list and accept queue during connection handshake.
51 	 * The listening socket is the head for both lists.  Sockets created
52 	 * for connection requests are placed in the pending list until they
53 	 * are connected, at which point they are put in the accept queue list
54 	 * so they can be accepted in accept().  If accept() cannot accept the
55 	 * connection, it is marked as rejected so the cleanup function knows
56 	 * to clean up the socket.
57 	 */
58 	struct list_head pending_links;
59 	struct list_head accept_queue;
60 	bool rejected;
61 	struct delayed_work connect_work;
62 	struct delayed_work pending_work;
63 	struct delayed_work close_work;
64 	bool close_work_scheduled;
65 	u32 peer_shutdown;
66 	bool sent_request;
67 	bool ignore_connecting_rst;
68 
69 	/* Protected by lock_sock(sk) */
70 	u64 buffer_size;
71 	u64 buffer_min_size;
72 	u64 buffer_max_size;
73 
74 	/* Private to transport. */
75 	void *trans;
76 };
77 
78 s64 vsock_connectible_has_data(struct vsock_sock *vsk);
79 s64 vsock_stream_has_data(struct vsock_sock *vsk);
80 s64 vsock_stream_has_space(struct vsock_sock *vsk);
81 struct sock *vsock_create_connected(struct sock *parent);
82 void vsock_data_ready(struct sock *sk);
83 
84 /**** TRANSPORT ****/
85 
86 struct vsock_transport_recv_notify_data {
87 	u64 data1; /* Transport-defined. */
88 	u64 data2; /* Transport-defined. */
89 	bool notify_on_block;
90 };
91 
92 struct vsock_transport_send_notify_data {
93 	u64 data1; /* Transport-defined. */
94 	u64 data2; /* Transport-defined. */
95 };
96 
97 /* Transport features flags */
98 /* Transport provides host->guest communication */
99 #define VSOCK_TRANSPORT_F_H2G		0x00000001
100 /* Transport provides guest->host communication */
101 #define VSOCK_TRANSPORT_F_G2H		0x00000002
102 /* Transport provides DGRAM communication */
103 #define VSOCK_TRANSPORT_F_DGRAM		0x00000004
104 /* Transport provides local (loopback) communication */
105 #define VSOCK_TRANSPORT_F_LOCAL		0x00000008
106 
107 struct vsock_transport {
108 	struct module *module;
109 
110 	/* Initialize/tear-down socket. */
111 	int (*init)(struct vsock_sock *, struct vsock_sock *);
112 	void (*destruct)(struct vsock_sock *);
113 	void (*release)(struct vsock_sock *);
114 
115 	/* Cancel all pending packets sent on vsock. */
116 	int (*cancel_pkt)(struct vsock_sock *vsk);
117 
118 	/* Connections. */
119 	int (*connect)(struct vsock_sock *);
120 
121 	/* DGRAM. */
122 	int (*dgram_bind)(struct vsock_sock *, struct sockaddr_vm *);
123 	int (*dgram_dequeue)(struct vsock_sock *vsk, struct msghdr *msg,
124 			     size_t len, int flags);
125 	int (*dgram_enqueue)(struct vsock_sock *, struct sockaddr_vm *,
126 			     struct msghdr *, size_t len);
127 	bool (*dgram_allow)(u32 cid, u32 port);
128 
129 	/* STREAM. */
130 	/* TODO: stream_bind() */
131 	ssize_t (*stream_dequeue)(struct vsock_sock *, struct msghdr *,
132 				  size_t len, int flags);
133 	ssize_t (*stream_enqueue)(struct vsock_sock *, struct msghdr *,
134 				  size_t len);
135 	s64 (*stream_has_data)(struct vsock_sock *);
136 	s64 (*stream_has_space)(struct vsock_sock *);
137 	u64 (*stream_rcvhiwat)(struct vsock_sock *);
138 	bool (*stream_is_active)(struct vsock_sock *);
139 	bool (*stream_allow)(u32 cid, u32 port);
140 
141 	/* SEQ_PACKET. */
142 	ssize_t (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg,
143 				     int flags);
144 	int (*seqpacket_enqueue)(struct vsock_sock *vsk, struct msghdr *msg,
145 				 size_t len);
146 	bool (*seqpacket_allow)(u32 remote_cid);
147 	u32 (*seqpacket_has_data)(struct vsock_sock *vsk);
148 
149 	/* Notification. */
150 	int (*notify_poll_in)(struct vsock_sock *, size_t, bool *);
151 	int (*notify_poll_out)(struct vsock_sock *, size_t, bool *);
152 	int (*notify_recv_init)(struct vsock_sock *, size_t,
153 		struct vsock_transport_recv_notify_data *);
154 	int (*notify_recv_pre_block)(struct vsock_sock *, size_t,
155 		struct vsock_transport_recv_notify_data *);
156 	int (*notify_recv_pre_dequeue)(struct vsock_sock *, size_t,
157 		struct vsock_transport_recv_notify_data *);
158 	int (*notify_recv_post_dequeue)(struct vsock_sock *, size_t,
159 		ssize_t, bool, struct vsock_transport_recv_notify_data *);
160 	int (*notify_send_init)(struct vsock_sock *,
161 		struct vsock_transport_send_notify_data *);
162 	int (*notify_send_pre_block)(struct vsock_sock *,
163 		struct vsock_transport_send_notify_data *);
164 	int (*notify_send_pre_enqueue)(struct vsock_sock *,
165 		struct vsock_transport_send_notify_data *);
166 	int (*notify_send_post_enqueue)(struct vsock_sock *, ssize_t,
167 		struct vsock_transport_send_notify_data *);
168 	/* sk_lock held by the caller */
169 	void (*notify_buffer_size)(struct vsock_sock *, u64 *);
170 	int (*notify_set_rcvlowat)(struct vsock_sock *vsk, int val);
171 
172 	/* Shutdown. */
173 	int (*shutdown)(struct vsock_sock *, int);
174 
175 	/* Addressing. */
176 	u32 (*get_local_cid)(void);
177 
178 	/* Read a single skb */
179 	int (*read_skb)(struct vsock_sock *, skb_read_actor_t);
180 
181 	/* Zero-copy. */
182 	bool (*msgzerocopy_allow)(void);
183 };
184 
185 /**** CORE ****/
186 
187 int vsock_core_register(const struct vsock_transport *t, int features);
188 void vsock_core_unregister(const struct vsock_transport *t);
189 
190 /* The transport may downcast this to access transport-specific functions */
191 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk);
192 
193 /**** UTILS ****/
194 
195 /* vsock_table_lock must be held */
196 static inline bool __vsock_in_bound_table(struct vsock_sock *vsk)
197 {
198 	return !list_empty(&vsk->bound_table);
199 }
200 
201 /* vsock_table_lock must be held */
202 static inline bool __vsock_in_connected_table(struct vsock_sock *vsk)
203 {
204 	return !list_empty(&vsk->connected_table);
205 }
206 
207 void vsock_add_pending(struct sock *listener, struct sock *pending);
208 void vsock_remove_pending(struct sock *listener, struct sock *pending);
209 void vsock_enqueue_accept(struct sock *listener, struct sock *connected);
210 void vsock_insert_connected(struct vsock_sock *vsk);
211 void vsock_remove_bound(struct vsock_sock *vsk);
212 void vsock_remove_connected(struct vsock_sock *vsk);
213 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr);
214 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src,
215 					 struct sockaddr_vm *dst);
216 void vsock_remove_sock(struct vsock_sock *vsk);
217 void vsock_for_each_connected_socket(struct vsock_transport *transport,
218 				     void (*fn)(struct sock *sk));
219 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk);
220 bool vsock_find_cid(unsigned int cid);
221 
222 /**** TAP ****/
223 
224 struct vsock_tap {
225 	struct net_device *dev;
226 	struct module *module;
227 	struct list_head list;
228 };
229 
230 int vsock_add_tap(struct vsock_tap *vt);
231 int vsock_remove_tap(struct vsock_tap *vt);
232 void vsock_deliver_tap(struct sk_buff *build_skb(void *opaque), void *opaque);
233 int __vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
234 				int flags);
235 int vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
236 			      int flags);
237 int __vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
238 			  size_t len, int flags);
239 int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
240 			size_t len, int flags);
241 
242 #ifdef CONFIG_BPF_SYSCALL
243 extern struct proto vsock_proto;
244 int vsock_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
245 void __init vsock_bpf_build_proto(void);
246 #else
247 static inline void __init vsock_bpf_build_proto(void)
248 {}
249 #endif
250 
251 static inline bool vsock_msgzerocopy_allow(const struct vsock_transport *t)
252 {
253 	return t->msgzerocopy_allow && t->msgzerocopy_allow();
254 }
255 #endif /* __AF_VSOCK_H__ */
256