1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3  * VMware vSockets Driver
4  *
5  * Copyright (C) 2007-2013 VMware, Inc. All rights reserved.
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the Free
9  * Software Foundation version 2 and no later version.
10  *
11  * This program is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  */
16 
17 #ifndef _UAPI_VM_SOCKETS_H
18 #define _UAPI_VM_SOCKETS_H
19 
20 #include <linux/socket.h>
21 #include <linux/types.h>
22 
23 /* Option name for STREAM socket buffer size.  Use as the option name in
24  * setsockopt(3) or getsockopt(3) to set or get an unsigned long long that
25  * specifies the size of the buffer underlying a vSockets STREAM socket.
26  * Value is clamped to the MIN and MAX.
27  */
28 
29 #define SO_VM_SOCKETS_BUFFER_SIZE 0
30 
31 /* Option name for STREAM socket minimum buffer size.  Use as the option name
32  * in setsockopt(3) or getsockopt(3) to set or get an unsigned long long that
33  * specifies the minimum size allowed for the buffer underlying a vSockets
34  * STREAM socket.
35  */
36 
37 #define SO_VM_SOCKETS_BUFFER_MIN_SIZE 1
38 
39 /* Option name for STREAM socket maximum buffer size.  Use as the option name
40  * in setsockopt(3) or getsockopt(3) to set or get an unsigned long long
41  * that specifies the maximum size allowed for the buffer underlying a
42  * vSockets STREAM socket.
43  */
44 
45 #define SO_VM_SOCKETS_BUFFER_MAX_SIZE 2
46 
47 /* Option name for socket peer's host-specific VM ID.  Use as the option name
48  * in getsockopt(3) to get a host-specific identifier for the peer endpoint's
49  * VM.  The identifier is a signed integer.
50  * Only available for hypervisor endpoints.
51  */
52 
53 #define SO_VM_SOCKETS_PEER_HOST_VM_ID 3
54 
55 /* Option name for determining if a socket is trusted.  Use as the option name
56  * in getsockopt(3) to determine if a socket is trusted.  The value is a
57  * signed integer.
58  */
59 
60 #define SO_VM_SOCKETS_TRUSTED 5
61 
62 /* Option name for STREAM socket connection timeout.  Use as the option name
63  * in setsockopt(3) or getsockopt(3) to set or get the connection
64  * timeout for a STREAM socket.
65  */
66 
67 #define SO_VM_SOCKETS_CONNECT_TIMEOUT 6
68 
69 /* Option name for using non-blocking send/receive.  Use as the option name
70  * for setsockopt(3) or getsockopt(3) to set or get the non-blocking
71  * transmit/receive flag for a STREAM socket.  This flag determines whether
72  * send() and recv() can be called in non-blocking contexts for the given
73  * socket.  The value is a signed integer.
74  *
75  * This option is only relevant to kernel endpoints, where descheduling the
76  * thread of execution is not allowed, for example, while holding a spinlock.
77  * It is not to be confused with conventional non-blocking socket operations.
78  *
79  * Only available for hypervisor endpoints.
80  */
81 
82 #define SO_VM_SOCKETS_NONBLOCK_TXRX 7
83 
84 /* The vSocket equivalent of INADDR_ANY.  This works for the svm_cid field of
85  * sockaddr_vm and indicates the context ID of the current endpoint.
86  */
87 
88 #define VMADDR_CID_ANY -1U
89 
90 /* Bind to any available port.  Works for the svm_port field of
91  * sockaddr_vm.
92  */
93 
94 #define VMADDR_PORT_ANY -1U
95 
96 /* Use this as the destination CID in an address when referring to the
97  * hypervisor.  VMCI relies on it being 0, but this would be useful for other
98  * transports too.
99  */
100 
101 #define VMADDR_CID_HYPERVISOR 0
102 
103 /* Use this as the destination CID in an address when referring to the
104  * local communication (loopback).
105  * (This was VMADDR_CID_RESERVED, but even VMCI doesn't use it anymore,
106  * it was a legacy value from an older release).
107  */
108 
109 #define VMADDR_CID_LOCAL 1
110 
111 /* Use this as the destination CID in an address when referring to the host
112  * (any process other than the hypervisor).  VMCI relies on it being 2, but
113  * this would be useful for other transports too.
114  */
115 
116 #define VMADDR_CID_HOST 2
117 
118 /* The current default use case for the vsock channel is the following:
119  * local vsock communication between guest and host and nested VMs setup.
120  * In addition to this, implicitly, the vsock packets are forwarded to the host
121  * if no host->guest vsock transport is set.
122  *
123  * Set this flag value in the sockaddr_vm corresponding field if the vsock
124  * packets need to be always forwarded to the host. Using this behavior,
125  * vsock communication between sibling VMs can be setup.
126  *
127  * This way can explicitly distinguish between vsock channels created for
128  * different use cases, such as nested VMs (or local communication between
129  * guest and host) and sibling VMs.
130  *
131  * The flag can be set in the connect logic in the user space application flow.
132  * In the listen logic (from kernel space) the flag is set on the remote peer
133  * address. This happens for an incoming connection when it is routed from the
134  * host and comes from the guest (local CID and remote CID > VMADDR_CID_HOST).
135  */
136 #define VMADDR_FLAG_TO_HOST 0x01
137 
138 /* Invalid vSockets version. */
139 
140 #define VM_SOCKETS_INVALID_VERSION -1U
141 
142 /* The epoch (first) component of the vSockets version.  A single byte
143  * representing the epoch component of the vSockets version.
144  */
145 
146 #define VM_SOCKETS_VERSION_EPOCH(_v) (((_v) & 0xFF000000) >> 24)
147 
148 /* The major (second) component of the vSockets version.   A single byte
149  * representing the major component of the vSockets version.  Typically
150  * changes for every major release of a product.
151  */
152 
153 #define VM_SOCKETS_VERSION_MAJOR(_v) (((_v) & 0x00FF0000) >> 16)
154 
155 /* The minor (third) component of the vSockets version.  Two bytes representing
156  * the minor component of the vSockets version.
157  */
158 
159 #define VM_SOCKETS_VERSION_MINOR(_v) (((_v) & 0x0000FFFF))
160 
161 /* Address structure for vSockets.   The address family should be set to
162  * AF_VSOCK.  The structure members should all align on their natural
163  * boundaries without resorting to compiler packing directives.  The total size
164  * of this structure should be exactly the same as that of struct sockaddr.
165  */
166 
167 struct sockaddr_vm {
168 	__kernel_sa_family_t svm_family;
169 	unsigned short svm_reserved1;
170 	unsigned int svm_port;
171 	unsigned int svm_cid;
172 	__u8 svm_flags;
173 	unsigned char svm_zero[sizeof(struct sockaddr) -
174 			       sizeof(sa_family_t) -
175 			       sizeof(unsigned short) -
176 			       sizeof(unsigned int) -
177 			       sizeof(unsigned int) -
178 			       sizeof(__u8)];
179 };
180 
181 #define IOCTL_VM_SOCKETS_GET_LOCAL_CID		_IO(7, 0xb9)
182 
183 #endif /* _UAPI_VM_SOCKETS_H */
184