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
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
<?php
namespace PhpZip\Crypto;
use PhpZip\Exception\ZipAuthenticationException;
use PhpZip\Exception\ZipCryptoException;
use PhpZip\Model\ZipEntry;
use PhpZip\Util\CryptoUtil;
use PhpZip\Util\PackUtil;
/**
* Traditional PKWARE Encryption Engine.
*
* @see https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT .ZIP File Format Specification
* @author Ne-Lexa alexey@nelexa.ru
* @license MIT
*/
class TraditionalPkwareEncryptionEngine implements ZipEncryptionEngine
{
/**
* Encryption header size
*/
const STD_DEC_HDR_SIZE = 12;
/**
* Crc table
*
* @var array
*/
private static $CRC_TABLE = [
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
];
/**
* Encryption keys
*
* @var array
*/
private $keys = [];
/**
* @var ZipEntry
*/
private $entry;
/**
* ZipCryptoEngine constructor.
*
* @param ZipEntry $entry
*/
public function __construct(ZipEntry $entry)
{
$this->entry = $entry;
}
/**
* Initial keys
*
* @param string $password
*/
private function initKeys($password)
{
$this->keys[0] = 305419896;
$this->keys[1] = 591751049;
$this->keys[2] = 878082192;
foreach (unpack('C*', $password) as $b) {
$this->updateKeys($b);
}
}
/**
* Update keys.
*
* @param string $charAt
*/
private function updateKeys($charAt)
{
$this->keys[0] = self::crc32($this->keys[0], $charAt);
$this->keys[1] = $this->keys[1] + ($this->keys[0] & 0xff);
$this->keys[1] = PackUtil::toSignedInt32($this->keys[1] * 134775813 + 1);
$this->keys[2] = PackUtil::toSignedInt32(self::crc32($this->keys[2], ($this->keys[1] >> 24) & 0xff));
}
/**
* Update crc.
*
* @param int $oldCrc
* @param string $charAt
* @return int
*/
private function crc32($oldCrc, $charAt)
{
return (($oldCrc >> 8) & 0xffffff) ^ self::$CRC_TABLE[($oldCrc ^ $charAt) & 0xff];
}
/**
* @param string $content
* @return string
* @throws ZipAuthenticationException
*/
public function decrypt($content)
{
$password = $this->entry->getPassword();
$this->initKeys($password);
$headerBytes = array_values(unpack('C*', substr($content, 0, self::STD_DEC_HDR_SIZE)));
$byte = 0;
foreach ($headerBytes as &$byte) {
$byte = ($byte ^ $this->decryptByte()) & 0xff;
$this->updateKeys($byte);
}
if ($this->entry->getGeneralPurposeBitFlag(ZipEntry::GPBF_DATA_DESCRIPTOR)) {
// compare against the file type from extended local headers
$checkByte = ($this->entry->getDosTime() >> 8) & 0xff;
} else {
// compare against the CRC otherwise
$checkByte = ($this->entry->getCrc() >> 24) & 0xff;
}
if ($byte !== $checkByte) {
throw new ZipAuthenticationException("Bad password for entry " . $this->entry->getName());
}
$outputContent = "";
foreach (unpack('C*', substr($content, self::STD_DEC_HDR_SIZE)) as $val) {
$val = ($val ^ $this->decryptByte()) & 0xff;
$this->updateKeys($val);
$outputContent .= pack('c', $val);
}
return $outputContent;
}
/**
* Decrypt byte.
*
* @return int
*/
private function decryptByte()
{
$temp = $this->keys[2] | 2;
return (($temp * ($temp ^ 1)) >> 8) & 0xffffff;
}
/**
* Encryption data
*
* @param string $data
* @return string
*/
public function encrypt($data)
{
$crc = $this->entry->isDataDescriptorRequired() ?
($this->entry->getDosTime() & 0x0000ffff) << 16 :
$this->entry->getCrc();
$headerBytes = CryptoUtil::randomBytes(self::STD_DEC_HDR_SIZE);
// Initialize again since the generated bytes were encrypted.
$password = $this->entry->getPassword();
$this->initKeys($password);
$headerBytes[self::STD_DEC_HDR_SIZE - 1] = pack('c', ($crc >> 24) & 0xff);
$headerBytes[self::STD_DEC_HDR_SIZE - 2] = pack('c', ($crc >> 16) & 0xff);
$headerBytes = $this->encryptData($headerBytes);
return $headerBytes . $this->encryptData($data);
}
/**
* @param string $content
* @return string
* @throws ZipCryptoException
*/
private function encryptData($content)
{
if (null === $content) {
throw new ZipCryptoException('content is null');
}
$buff = '';
foreach (unpack('C*', $content) as $val) {
$buff .= pack('c', $this->encryptByte($val));
}
return $buff;
}
/**
* @param int $byte
* @return int
*/
private function encryptByte($byte)
{
$tempVal = $byte ^ $this->decryptByte() & 0xff;
$this->updateKeys($byte);
return $tempVal;
}
}
|
