aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/hv/hv_kvp.h
blob: 9b765d7df83808b855630f26183fbb5ba527c103 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/*
 * An implementation of HyperV key value pair (KVP) functionality for Linux.
 *
 *
 * Copyright (C) 2010, Novell, Inc.
 * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 * NON INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 */
#ifndef	_KVP_H
#define	_KVP_H_

/*
 * Maximum value size - used for both key names and value data, and includes
 * any applicable NULL terminators.
 *
 * Note:  This limit is somewhat arbitrary, but falls easily within what is
 * supported for all native guests (back to Win 2000) and what is reasonable
 * for the IC KVP exchange functionality.  Note that Windows Me/98/95 are
 * limited to 255 character key names.
 *
 * MSDN recommends not storing data values larger than 2048 bytes in the
 * registry.
 *
 * Note:  This value is used in defining the KVP exchange message - this value
 * cannot be modified without affecting the message size and compatibility.
 */

/*
 * bytes, including any null terminators
 */
#define HV_KVP_EXCHANGE_MAX_VALUE_SIZE          (2048)


/*
 * Maximum key size - the registry limit for the length of an entry name
 * is 256 characters, including the null terminator
 */

#define HV_KVP_EXCHANGE_MAX_KEY_SIZE            (512)

/*
 * In Linux, we implement the KVP functionality in two components:
 * 1) The kernel component which is packaged as part of the hv_utils driver
 * is responsible for communicating with the host and responsible for
 * implementing the host/guest protocol. 2) A user level daemon that is
 * responsible for data gathering.
 *
 * Host/Guest Protocol: The host iterates over an index and expects the guest
 * to assign a key name to the index and also return the value corresponding to
 * the key. The host will have atmost one KVP transaction outstanding at any
 * given point in time. The host side iteration stops when the guest returns
 * an error. Microsoft has specified the following mapping of key names to
 * host specified index:
 *
 *	Index		Key Name
 *	0		FullyQualifiedDomainName
 *	1		IntegrationServicesVersion
 *	2		NetworkAddressIPv4
 *	3		NetworkAddressIPv6
 *	4		OSBuildNumber
 *	5		OSName
 *	6		OSMajorVersion
 *	7		OSMinorVersion
 *	8		OSVersion
 *	9		ProcessorArchitecture
 *
 * The Windows host expects the Key Name and Key Value to be encoded in utf16.
 *
 * Guest Kernel/KVP Daemon Protocol: As noted earlier, we implement all of the
 * data gathering functionality in a user mode daemon. The user level daemon
 * is also responsible for binding the key name to the index as well. The
 * kernel and user-level daemon communicate using a connector channel.
 *
 * The user mode component first registers with the
 * the kernel component. Subsequently, the kernel component requests, data
 * for the specified keys. In response to this message the user mode component
 * fills in the value corresponding to the specified key. We overload the
 * sequence field in the cn_msg header to define our KVP message types.
 *
 *
 * The kernel component simply acts as a conduit for communication between the
 * Windows host and the user-level daemon. The kernel component passes up the
 * index received from the Host to the user-level daemon. If the index is
 * valid (supported), the corresponding key as well as its
 * value (both are strings) is returned. If the index is invalid
 * (not supported), a NULL key string is returned.
 */

/*
 *
 * The following definitions are shared with the user-mode component; do not
 * change any of this without making the corresponding changes in
 * the KVP user-mode component.
 */

#define CN_KVP_VAL             0x1 /* This supports queries from the kernel */
#define CN_KVP_USER_VAL       0x2 /* This supports queries from the user */

enum hv_ku_op {
	KVP_REGISTER = 0, /* Register the user mode component */
	KVP_KERNEL_GET, /* Kernel is requesting the value */
	KVP_KERNEL_SET, /* Kernel is providing the value */
	KVP_USER_GET,  /* User is requesting the value */
	KVP_USER_SET  /* User is providing the value */
};

struct hv_ku_msg {
	__u32 kvp_index; /* Key index */
	__u8  kvp_key[HV_KVP_EXCHANGE_MAX_KEY_SIZE]; /* Key name */
	__u8  kvp_value[HV_KVP_EXCHANGE_MAX_VALUE_SIZE]; /* Key  value */
};




#ifdef __KERNEL__

/*
 * Registry value types.
 */

#define REG_SZ 1

enum hv_kvp_exchg_op {
	KVP_OP_GET = 0,
	KVP_OP_SET,
	KVP_OP_DELETE,
	KVP_OP_ENUMERATE,
	KVP_OP_COUNT /* Number of operations, must be last. */
};

enum hv_kvp_exchg_pool {
	KVP_POOL_EXTERNAL = 0,
	KVP_POOL_GUEST,
	KVP_POOL_AUTO,
	KVP_POOL_AUTO_EXTERNAL,
	KVP_POOL_AUTO_INTERNAL,
	KVP_POOL_COUNT /* Number of pools, must be last. */
};

struct hv_kvp_hdr {
	u8 operation;
	u8 pool;
};

struct hv_kvp_exchg_msg_value {
	u32 value_type;
	u32 key_size;
	u32 value_size;
	u8 key[HV_KVP_EXCHANGE_MAX_KEY_SIZE];
	u8 value[HV_KVP_EXCHANGE_MAX_VALUE_SIZE];
};

struct hv_kvp_msg_enumerate {
	u32 index;
	struct hv_kvp_exchg_msg_value data;
};

struct hv_kvp_msg {
	struct hv_kvp_hdr	kvp_hdr;
	struct hv_kvp_msg_enumerate	kvp_data;
};

int hv_kvp_init(struct hv_util_service *);
void hv_kvp_deinit(void);
void hv_kvp_onchannelcallback(void *);

#endif /* __KERNEL__ */
#endif	/* _KVP_H */