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