summaryrefslogtreecommitdiff
path: root/isohybrid-acritox
blob: 440e7569cff54291757687a22ab5eeeef4976196 (plain)
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
#!/usr/bin/perl
# isohybrid-acritox - written by Andreas Loibl <andreas@andreas-loibl.de>
# 
# Post-process a hybrid-ISO-image generated with isohybrid-bg2
# by injecting an "Apple Partition Map" into the image and appending a HFS+-partiton
# and a FAT-partition to allow "hybrid booting" as CD-ROM (EFI or El Torito) or as
# a hard-drive on Intel-Macs (EFI) and PCs (EFI or MBR).

$bs=0x0200; $block0='45520200eb5f90'; #  512  -  add    (%eax),%al
$bs=0x0400; $block0='45520400eb5f90'; # 1024  -  add    $0x0,%al

# Apple Partition Map entries:
$pm1='504d000000000004000000010000000f4170706c650000000000000000000000000000000000000000000000000000004170706c655f706172746974696f6e5f6d617000000000000000000000000000000000000000000f00000003';
$pm2='504d00000000000400000010000000014d6163696e746f736800000000000000000000000000000000000000000000004170706c655f4472697665725f41544150490000000000000000000000000000000000000000000100000303000000002674b000000000000000000000000000000000000000eaeb0000000000000000000000000000000049534f43';
$pm3='504d00000000000400000400000005006469736b20696d616765000000000000000000000000000000000000000000004170706c655f4846530000000000000000000000000000000000000000000000000000000000040040000033';
$pm4='504d000000000004000009000000001000000000000000000000000000000000000000000000000000000000000000004170706c655f4672656500000000000000000000000000000000000000000000000000000000001000000001';

die "Usage: $0 <isohybrid-bg2.iso> <HFS+-image> <FAT-image>\n" if $#ARGV != 2;

($file, $part, $fat) = @ARGV;
open(FILE, "+< $file\0") or die "$0: cannot open $file: $!\n";
binmode FILE;

open(PART, "< $part\0") or die "$0: cannot open $part: $!\n";
binmode PART;

open(FAT, "< $fat\0") or die "$0: cannot open $fat: $!\n";
binmode FAT;

# Check if image has already been "patched" (i.e. it has the APM signature from $block0)
seek(FILE, 0, SEEK_SET) or die "$0: $file: $!\n";
read(FILE, $test, 2) == 2 or die "$0: $file: read error\n";
die "$file seems to have an APM signature already...\n" if($test eq 'ER');

# Check if image is a isohybrid-bg2 image (i.e. it has GRUB in its MBR)
seek(FILE, 0x180, SEEK_SET) or die "$0: $file: $!\n";
read(FILE, $test, 4) == 4 or die "$0: $file: read error\n";
die "$file seems not to have GRUB in its MBR (is this a isohybrid-bg2 image?)\n" if($test ne 'GRUB');

# Check if partition contains a HFS+ filesystem
seek(PART, 0x400, SEEK_SET) or die "$0: $file: $!\n";
read(PART, $test, 2) == 2 or die "$0: $file: read error\n";
die "$part doesn't seem to contain a HFS+ filesystem\n" if($test ne 'H+');

# Get the total size of the image
(@imgstat = stat(FILE)) or die "$0: $file: $!\n";
$imgsize = $imgstat[7];
if (!$imgsize) {
    die "$0: $file: cannot determine length of file\n";
}
# Target image size: round up to a multiple of $bs*512
$cylsize = $bs*512;
$frac = $imgsize % $cylsize;
$padding = ($frac > 0) ? $cylsize - $frac : 0;
$imgsize += $padding;

# Get the total size of the partiton
(@partstat = stat(PART)) or die "$0: $part: $!\n";
$partsize = $partstat[7];
if (!$partsize) {
    die "$0: $part: cannot determine length of file\n";
}

# Get the total size of the partiton
(@fatstat = stat(FAT)) or die "$0: $part: $!\n";
$fatsize = $fatstat[7];
if (!$fatsize) {
    die "$0: $part: cannot determine length of file\n";
}

seek(FILE, 0, SEEK_SET) or die "$0: $file: $!\n";
print FILE pack('H*',$block0);
seek(FILE, $bs*1, SEEK_SET) or die "$0: $file: $!\n";
print FILE pack('H*',$pm1);
seek(FILE, $bs*2, SEEK_SET) or die "$0: $file: $!\n";
print FILE pack('H*',$pm2);
seek(FILE, $bs*3, SEEK_SET) or die "$0: $file: $!\n";
print FILE pack('H*',$pm3);
seek(FILE, $bs*4, SEEK_SET) or die "$0: $file: $!\n";
print FILE pack('H*',$pm4);

# Pad the image to a fake cylinder boundary
seek(FILE, $imgstat[7], SEEK_SET) or die "$0: $file: $!\n";
if ($padding) {
    print FILE "\0" x $padding;
}

# Append partition to image
seek(PART, 0, SEEK_SET) or die "$0: $file: $!\n";
read PART, $partition, $partsize;
print FILE $partition;

# Pad the partition to a fake cylinder boundary
$frac = $partsize % $cylsize;
$padding = ($frac > 0) ? $cylsize - $frac : 0;
if ($padding) {
    print FILE "\0" x $padding;
}
$partsize += $padding;

# Adjust $pm3 (Apple_HFS)
# "physical block start" and "physical block count" of partition:
seek(FILE, $bs*3+8, SEEK_SET) or die "$0: $file: $!\n";
print FILE pack('NN', $imgsize/$bs, $partsize/$bs);
# "logical block start" and "logical block count" of partition:
seek(FILE, $bs*3+80, SEEK_SET) or die "$0: $file: $!\n";
print FILE pack('NN', 0, $partsize/$bs);
# Adjust $pm4 (Apple_Free)
# "physical block start" of partition:
seek(FILE, $bs*4+8, SEEK_SET) or die "$0: $file: $!\n";
print FILE pack('N', $imgsize/$bs + $partsize/$bs);

$imgsize += $partsize;
seek(FILE, $imgsize, SEEK_SET) or die "$0: $file: $!\n";

# Target image size: round up to a multiple of 1MB
$cylsize = 64*32*512; # 1MB
$frac = $imgsize % $cylsize;
$padding = ($frac > 0) ? $cylsize - $frac : 0;
$imgsize += $padding;
if ($padding) {
    print FILE "\0" x $padding;
}

# Append FAT partition to image
read FAT, $partition, $fatsize;
print FILE $partition;

# Pad the partition to a fake cylinder boundary
$frac = $fatsize % $cylsize;
$padding = ($frac > 0) ? $cylsize - $frac : 0;
if ($padding) {
    print FILE "\0" x $padding;
}
$fatsize += $padding;

# Adjust MBR partition table
$fstype  = 0xEF;
$pentry  = 2;

seek(FILE, 430+16*$pentry, SEEK_SET) or die "$0: $file: $!\n";
print FILE pack("CCCCCCCCVV", 0x80, 0xfe, 0xff, 0xff, $fstype, 0xfe, 0xff, 0xff, $imgsize/512, $fatsize/512);

# Delete ISO9660 partition entry from MBR-partition-table
seek(FILE, 430+16*1, SEEK_SET) or die "$0: $file: $!\n";
print FILE "\0" x 16;

$imgsize += $fatsize;

# Done...
close(PART);
close(FILE);

exit 0;