xref: /linux/include/uapi/linux/vm_sockets.h (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
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_OLD 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 #define SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW 8
85 
86 #if !defined(__KERNEL__)
87 #if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__))
88 #define SO_VM_SOCKETS_CONNECT_TIMEOUT SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD
89 #else
90 #define SO_VM_SOCKETS_CONNECT_TIMEOUT \
91 	(sizeof(time_t) == sizeof(__kernel_long_t) ? SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD : SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW)
92 #endif
93 #endif
94 
95 /* The vSocket equivalent of INADDR_ANY.  This works for the svm_cid field of
96  * sockaddr_vm and indicates the context ID of the current endpoint.
97  */
98 
99 #define VMADDR_CID_ANY -1U
100 
101 /* Bind to any available port.  Works for the svm_port field of
102  * sockaddr_vm.
103  */
104 
105 #define VMADDR_PORT_ANY -1U
106 
107 /* Use this as the destination CID in an address when referring to the
108  * hypervisor.  VMCI relies on it being 0, but this would be useful for other
109  * transports too.
110  */
111 
112 #define VMADDR_CID_HYPERVISOR 0
113 
114 /* Use this as the destination CID in an address when referring to the
115  * local communication (loopback).
116  * (This was VMADDR_CID_RESERVED, but even VMCI doesn't use it anymore,
117  * it was a legacy value from an older release).
118  */
119 
120 #define VMADDR_CID_LOCAL 1
121 
122 /* Use this as the destination CID in an address when referring to the host
123  * (any process other than the hypervisor).  VMCI relies on it being 2, but
124  * this would be useful for other transports too.
125  */
126 
127 #define VMADDR_CID_HOST 2
128 
129 /* The current default use case for the vsock channel is the following:
130  * local vsock communication between guest and host and nested VMs setup.
131  * In addition to this, implicitly, the vsock packets are forwarded to the host
132  * if no host->guest vsock transport is set.
133  *
134  * Set this flag value in the sockaddr_vm corresponding field if the vsock
135  * packets need to be always forwarded to the host. Using this behavior,
136  * vsock communication between sibling VMs can be setup.
137  *
138  * This way can explicitly distinguish between vsock channels created for
139  * different use cases, such as nested VMs (or local communication between
140  * guest and host) and sibling VMs.
141  *
142  * The flag can be set in the connect logic in the user space application flow.
143  * In the listen logic (from kernel space) the flag is set on the remote peer
144  * address. This happens for an incoming connection when it is routed from the
145  * host and comes from the guest (local CID and remote CID > VMADDR_CID_HOST).
146  */
147 #define VMADDR_FLAG_TO_HOST 0x01
148 
149 /* Invalid vSockets version. */
150 
151 #define VM_SOCKETS_INVALID_VERSION -1U
152 
153 /* The epoch (first) component of the vSockets version.  A single byte
154  * representing the epoch component of the vSockets version.
155  */
156 
157 #define VM_SOCKETS_VERSION_EPOCH(_v) (((_v) & 0xFF000000) >> 24)
158 
159 /* The major (second) component of the vSockets version.   A single byte
160  * representing the major component of the vSockets version.  Typically
161  * changes for every major release of a product.
162  */
163 
164 #define VM_SOCKETS_VERSION_MAJOR(_v) (((_v) & 0x00FF0000) >> 16)
165 
166 /* The minor (third) component of the vSockets version.  Two bytes representing
167  * the minor component of the vSockets version.
168  */
169 
170 #define VM_SOCKETS_VERSION_MINOR(_v) (((_v) & 0x0000FFFF))
171 
172 /* Address structure for vSockets.   The address family should be set to
173  * AF_VSOCK.  The structure members should all align on their natural
174  * boundaries without resorting to compiler packing directives.  The total size
175  * of this structure should be exactly the same as that of struct sockaddr.
176  */
177 
178 struct sockaddr_vm {
179 	__kernel_sa_family_t svm_family;
180 	unsigned short svm_reserved1;
181 	unsigned int svm_port;
182 	unsigned int svm_cid;
183 	__u8 svm_flags;
184 	unsigned char svm_zero[sizeof(struct sockaddr) -
185 			       sizeof(sa_family_t) -
186 			       sizeof(unsigned short) -
187 			       sizeof(unsigned int) -
188 			       sizeof(unsigned int) -
189 			       sizeof(__u8)];
190 };
191 
192 #define IOCTL_VM_SOCKETS_GET_LOCAL_CID		_IO(7, 0xb9)
193 
194 #endif /* _UAPI_VM_SOCKETS_H */
195