vm_sockets.h

  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#ifndef __KERNEL__
 21#include <sys/socket.h>        /* for struct sockaddr and sa_family_t */
 22#endif
 23
 24#include <linux/socket.h>
 25#include <linux/types.h>
 26
 27/* Option name for STREAM socket buffer size.  Use as the option name in
 28 * setsockopt(3) or getsockopt(3) to set or get an unsigned long long that
 29 * specifies the size of the buffer underlying a vSockets STREAM socket.
 30 * Value is clamped to the MIN and MAX.
 31 */
 32
 33#define SO_VM_SOCKETS_BUFFER_SIZE 0
 34
 35/* Option name for STREAM socket minimum buffer size.  Use as the option name
 36 * in setsockopt(3) or getsockopt(3) to set or get an unsigned long long that
 37 * specifies the minimum size allowed for the buffer underlying a vSockets
 38 * STREAM socket.
 39 */
 40
 41#define SO_VM_SOCKETS_BUFFER_MIN_SIZE 1
 42
 43/* Option name for STREAM socket maximum buffer size.  Use as the option name
 44 * in setsockopt(3) or getsockopt(3) to set or get an unsigned long long
 45 * that specifies the maximum size allowed for the buffer underlying a
 46 * vSockets STREAM socket.
 47 */
 48
 49#define SO_VM_SOCKETS_BUFFER_MAX_SIZE 2
 50
 51/* Option name for socket peer's host-specific VM ID.  Use as the option name
 52 * in getsockopt(3) to get a host-specific identifier for the peer endpoint's
 53 * VM.  The identifier is a signed integer.
 54 * Only available for hypervisor endpoints.
 55 */
 56
 57#define SO_VM_SOCKETS_PEER_HOST_VM_ID 3
 58
 59/* Option name for determining if a socket is trusted.  Use as the option name
 60 * in getsockopt(3) to determine if a socket is trusted.  The value is a
 61 * signed integer.
 62 */
 63
 64#define SO_VM_SOCKETS_TRUSTED 5
 65
 66/* Option name for STREAM socket connection timeout.  Use as the option name
 67 * in setsockopt(3) or getsockopt(3) to set or get the connection
 68 * timeout for a STREAM socket.
 69 */
 70
 71#define SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD 6
 72
 73/* Option name for using non-blocking send/receive.  Use as the option name
 74 * for setsockopt(3) or getsockopt(3) to set or get the non-blocking
 75 * transmit/receive flag for a STREAM socket.  This flag determines whether
 76 * send() and recv() can be called in non-blocking contexts for the given
 77 * socket.  The value is a signed integer.
 78 *
 79 * This option is only relevant to kernel endpoints, where descheduling the
 80 * thread of execution is not allowed, for example, while holding a spinlock.
 81 * It is not to be confused with conventional non-blocking socket operations.
 82 *
 83 * Only available for hypervisor endpoints.
 84 */
 85
 86#define SO_VM_SOCKETS_NONBLOCK_TXRX 7
 87
 88#define SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW 8
 89
 90#if !defined(__KERNEL__)
 91#if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__))
 92#define SO_VM_SOCKETS_CONNECT_TIMEOUT SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD
 93#else
 94#define SO_VM_SOCKETS_CONNECT_TIMEOUT \
 95	(sizeof(time_t) == sizeof(__kernel_long_t) ? SO_VM_SOCKETS_CONNECT_TIMEOUT_OLD : SO_VM_SOCKETS_CONNECT_TIMEOUT_NEW)
 96#endif
 97#endif
 98
 99/* The vSocket equivalent of INADDR_ANY.  This works for the svm_cid field of
100 * sockaddr_vm and indicates the context ID of the current endpoint.
101 */
102
103#define VMADDR_CID_ANY -1U
104
105/* Bind to any available port.  Works for the svm_port field of
106 * sockaddr_vm.
107 */
108
109#define VMADDR_PORT_ANY -1U
110
111/* Use this as the destination CID in an address when referring to the
112 * hypervisor.  VMCI relies on it being 0, but this would be useful for other
113 * transports too.
114 */
115
116#define VMADDR_CID_HYPERVISOR 0
117
118/* Use this as the destination CID in an address when referring to the
119 * local communication (loopback).
120 * (This was VMADDR_CID_RESERVED, but even VMCI doesn't use it anymore,
121 * it was a legacy value from an older release).
122 */
123
124#define VMADDR_CID_LOCAL 1
125
126/* Use this as the destination CID in an address when referring to the host
127 * (any process other than the hypervisor).  VMCI relies on it being 2, but
128 * this would be useful for other transports too.
129 */
130
131#define VMADDR_CID_HOST 2
132
133/* The current default use case for the vsock channel is the following:
134 * local vsock communication between guest and host and nested VMs setup.
135 * In addition to this, implicitly, the vsock packets are forwarded to the host
136 * if no host->guest vsock transport is set.
137 *
138 * Set this flag value in the sockaddr_vm corresponding field if the vsock
139 * packets need to be always forwarded to the host. Using this behavior,
140 * vsock communication between sibling VMs can be setup.
141 *
142 * This way can explicitly distinguish between vsock channels created for
143 * different use cases, such as nested VMs (or local communication between
144 * guest and host) and sibling VMs.
145 *
146 * The flag can be set in the connect logic in the user space application flow.
147 * In the listen logic (from kernel space) the flag is set on the remote peer
148 * address. This happens for an incoming connection when it is routed from the
149 * host and comes from the guest (local CID and remote CID > VMADDR_CID_HOST).
150 */
151#define VMADDR_FLAG_TO_HOST 0x01
152
153/* Invalid vSockets version. */
154
155#define VM_SOCKETS_INVALID_VERSION -1U
156
157/* The epoch (first) component of the vSockets version.  A single byte
158 * representing the epoch component of the vSockets version.
159 */
160
161#define VM_SOCKETS_VERSION_EPOCH(_v) (((_v) & 0xFF000000) >> 24)
162
163/* The major (second) component of the vSockets version.   A single byte
164 * representing the major component of the vSockets version.  Typically
165 * changes for every major release of a product.
166 */
167
168#define VM_SOCKETS_VERSION_MAJOR(_v) (((_v) & 0x00FF0000) >> 16)
169
170/* The minor (third) component of the vSockets version.  Two bytes representing
171 * the minor component of the vSockets version.
172 */
173
174#define VM_SOCKETS_VERSION_MINOR(_v) (((_v) & 0x0000FFFF))
175
176/* Address structure for vSockets.   The address family should be set to
177 * AF_VSOCK.  The structure members should all align on their natural
178 * boundaries without resorting to compiler packing directives.  The total size
179 * of this structure should be exactly the same as that of struct sockaddr.
180 */
181
182struct sockaddr_vm {
183	__kernel_sa_family_t svm_family;
184	unsigned short svm_reserved1;
185	unsigned int svm_port;
186	unsigned int svm_cid;
187	__u8 svm_flags;
188	unsigned char svm_zero[sizeof(struct sockaddr) -
189			       sizeof(sa_family_t) -
190			       sizeof(unsigned short) -
191			       sizeof(unsigned int) -
192			       sizeof(unsigned int) -
193			       sizeof(__u8)];
194};
195
196#define IOCTL_VM_SOCKETS_GET_LOCAL_CID		_IO(7, 0xb9)
197
198/* MSG_ZEROCOPY notifications are encoded in the standard error format,
199 * sock_extended_err. See Documentation/networking/msg_zerocopy.rst in
200 * kernel source tree for more details.
201 */
202
203/* 'cmsg_level' field value of 'struct cmsghdr' for notification parsing
204 * when MSG_ZEROCOPY flag is used on transmissions.
205 */
206
207#define SOL_VSOCK	287
208
209/* 'cmsg_type' field value of 'struct cmsghdr' for notification parsing
210 * when MSG_ZEROCOPY flag is used on transmissions.
211 */
212
213#define VSOCK_RECVERR	1
214
215#endif /* _UAPI_VM_SOCKETS_H */