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
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
package org.openslx.util.vm;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.Arrays;
import org.apache.log4j.Logger;
import org.openslx.bwlp.thrift.iface.Virtualizer;
import org.openslx.thrifthelper.TConst;
import org.openslx.util.Util;
public class DiskImage
{
private static final Logger LOGGER = Logger.getLogger( DiskImage.class );
/**
* Big endian representation of the 4 bytes 'KDMV'
*/
private static final int VMDK_MAGIC = 0x4b444d56;
private static final int VDI_MAGIC = 0x7f10dabe;
/**
* Big endian representation of the 4 bytes 'QFI\xFB'
*/
private static final int QEMU_MAGIC = 0x514649fb;
public enum ImageFormat
{
VMDK( "vmdk" ), QCOW2( "qcow2" ), VDI( "vdi" );
public final String extension;
private ImageFormat( String extension )
{
this.extension = extension;
}
public static ImageFormat defaultForVirtualizer( Virtualizer virt )
{
if ( virt == null )
return null;
return defaultForVirtualizer( virt.virtId );
}
public static ImageFormat defaultForVirtualizer( String virtId )
{
if ( virtId == null )
return null;
if ( virtId.equals( TConst.VIRT_VMWARE ) )
return VMDK;
if ( virtId.equals( TConst.VIRT_VIRTUALBOX ) )
return VDI;
if ( virtId.equals( TConst.VIRT_QEMU ) )
return QCOW2;
return null;
}
}
public final boolean isStandalone;
public final boolean isCompressed;
public final boolean isSnapshot;
public final ImageFormat format;
public final String subFormat;
public final int hwVersion;
public final String diskDescription;
public ImageFormat getImageFormat()
{
return format;
}
public DiskImage( File disk ) throws FileNotFoundException, IOException, UnknownImageFormatException
{
LOGGER.debug( "Validating disk file: " + disk.getAbsolutePath() );
try ( RandomAccessFile file = new RandomAccessFile( disk, "r" ) ) {
// vmdk
boolean isVmdkMagic = ( file.readInt() == VMDK_MAGIC );
if ( isVmdkMagic || file.length() < 4096 ) {
if ( isVmdkMagic ) {
file.seek( 512 );
} else {
file.seek( 0 );
}
byte[] buffer = new byte[ (int)Math.min( 2048, file.length() ) ];
file.readFully( buffer );
VmwareConfig config;
try {
config = new VmwareConfig( buffer, findNull( buffer ) );
} catch ( UnsupportedVirtualizerFormatException e ) {
config = null;
}
if ( config != null ) {
String sf = config.get( "createType" );
String parent = config.get( "parentCID" );
if ( sf != null || parent != null ) {
subFormat = sf;
this.isStandalone = isStandaloneCreateType( subFormat, parent );
this.isCompressed = subFormat != null && subFormat.equalsIgnoreCase( "streamOptimized" );
this.isSnapshot = parent != null && !parent.equalsIgnoreCase( "ffffffff" );
this.format = ImageFormat.VMDK;
String hwv = config.get( "ddb.virtualHWVersion" );
if ( hwv == null ) {
this.hwVersion = 10;
} else {
this.hwVersion = Util.parseInt( hwv, 10 );
}
this.diskDescription = null;
return;
}
}
}
// Format spec from: https://forums.virtualbox.org/viewtopic.php?t=8046
// First 64 bytes are the opening tag: <<< .... >>>
// which we don't care about, then comes the VDI signature
file.seek( 64 );
if ( file.readInt() == VDI_MAGIC ) {
// skip the next 4 ints as they don't interest us:
// - VDI version
// - size of header, strangely irrelevant?
// - image type, 1 for dynamic allocated storage, 2 for fixed size
// - image flags, seem to be always 00 00 00 00
file.skipBytes( 4 * 4 );
// next 256 bytes are image description
byte[] imageDesc = new byte[ 256 ];
file.readFully( imageDesc );
// next sections are irrelevant (int if not specified):
// - offset blocks
// - offset data
// - cylinders
// - heads
// - sectors
// - sector size
// - <unused>
// - disk size (long = 8 bytes)
// - block size
// - block extra data
// - blocks in hdd
// - blocks allocated
file.skipBytes( 4 * 13 );
// now it gets interesting, UUID of VDI
byte[] diskUuid = new byte[ 16 ];
file.readFully( diskUuid );
// last snapshot uuid, mostly uninteresting since we don't support snapshots -> skip 16 bytes
// TODO: meaning of "uuid link"? for now, skip 16
file.skipBytes( 32 );
// parent uuid, indicator if this VDI is a snapshot or not
byte[] parentUuid = new byte[ 16 ];
file.readFully( parentUuid );
byte[] zeroUuid = new byte[ 16 ];
Arrays.fill( zeroUuid, (byte)0 );
this.isSnapshot = !Arrays.equals( parentUuid, zeroUuid );
// VDI does not seem to support split VDI files so always standalone
this.isStandalone = true;
// compression is done by sparsifying the disk files, there is no flag for it
this.isCompressed = false;
this.format = ImageFormat.VDI;
this.subFormat = null;
this.diskDescription = new String( imageDesc );
this.hwVersion = 0;
return;
}
// TODO: qcow
file.seek( 0 );
if ( file.readInt() == QEMU_MAGIC ) {
// dummy values
this.isStandalone = true;
this.isCompressed = false;
this.isSnapshot = false;
this.format = ImageFormat.QCOW2;
this.subFormat = null;
this.diskDescription = null;
this.hwVersion = 0;
return;
}
}
throw new UnknownImageFormatException();
}
private int findNull( byte[] buffer )
{
for ( int i = 0; i < buffer.length; ++i ) {
if ( buffer[i] == 0 )
return i;
}
return buffer.length;
}
private boolean isStandaloneCreateType( String type, String parent )
{
if ( type == null )
return false;
if ( parent != null && !parent.equalsIgnoreCase( "ffffffff" ) )
return false;
return type.equalsIgnoreCase( "streamOptimized" ) || type.equalsIgnoreCase( "monolithicSparse" );
}
public static class UnknownImageFormatException extends Exception
{
private static final long serialVersionUID = -6647935235475007171L;
}
}
|
