1<?php
2/**
3 * Portable PHP password hashing framework.
4 * @package phpass
5 * @since 2.5.0
6 * @version 0.5 / WordPress
7 * @link https://www.openwall.com/phpass/
8 */
9
10#
11# Portable PHP password hashing framework.
12#
13# Version 0.5.4 / WordPress.
14#
15# Written by Solar Designer <solar at openwall.com> in 2004-2006 and placed in
16# the public domain.  Revised in subsequent years, still public domain.
17#
18# There's absolutely no warranty.
19#
20# The homepage URL for this framework is:
21#
22#	http://www.openwall.com/phpass/
23#
24# Please be sure to update the Version line if you edit this file in any way.
25# It is suggested that you leave the main version number intact, but indicate
26# your project name (after the slash) and add your own revision information.
27#
28# Please do not change the "private" password hashing method implemented in
29# here, thereby making your hashes incompatible.  However, if you must, please
30# change the hash type identifier (the "$P$") to something different.
31#
32# Obviously, since this code is in the public domain, the above are not
33# requirements (there can be none), but merely suggestions.
34#
35
36/**
37 * Portable PHP password hashing framework.
38 *
39 * @package phpass
40 * @version 0.5 / WordPress
41 * @link https://www.openwall.com/phpass/
42 * @since 2.5.0
43 */
44class PasswordHash {
45    var $itoa64;
46    var $iteration_count_log2;
47    var $portable_hashes;
48    var $random_state;
49
50    function __construct($iteration_count_log2, $portable_hashes)
51    {
52        $this->itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
53
54        if ($iteration_count_log2 < 4 || $iteration_count_log2 > 31) {
55            $iteration_count_log2 = 8;
56        }
57        $this->iteration_count_log2 = $iteration_count_log2;
58
59        $this->portable_hashes = $portable_hashes;
60
61        $this->random_state = microtime();
62        if (function_exists('getmypid')) {
63            $this->random_state .= getmypid();
64        }
65    }
66
67    function PasswordHash($iteration_count_log2, $portable_hashes)
68    {
69        self::__construct($iteration_count_log2, $portable_hashes);
70    }
71
72    function get_random_bytes($count)
73    {
74        $output = '';
75        if (@is_readable('/dev/urandom') &&
76            ($fh = @fopen('/dev/urandom', 'rb'))) {
77            $output = fread($fh, $count);
78            fclose($fh);
79        }
80
81        if (strlen($output) < $count) {
82            $output = '';
83            for ($i = 0; $i < $count; $i += 16) {
84                $this->random_state =
85                    md5(microtime() . $this->random_state);
86                $output .= md5($this->random_state, TRUE);
87            }
88            $output = substr($output, 0, $count);
89        }
90
91        return $output;
92    }
93
94    function encode64($input, $count)
95    {
96        $output = '';
97        $i = 0;
98        do {
99            $value = ord($input[$i++]);
100            $output .= $this->itoa64[$value & 0x3f];
101            if ($i < $count) {
102                $value |= ord($input[$i]) << 8;
103            }
104            $output .= $this->itoa64[($value >> 6) & 0x3f];
105            if ($i++ >= $count) {
106                break;
107            }
108            if ($i < $count) {
109                $value |= ord($input[$i]) << 16;
110            }
111            $output .= $this->itoa64[($value >> 12) & 0x3f];
112            if ($i++ >= $count) {
113                break;
114            }
115            $output .= $this->itoa64[($value >> 18) & 0x3f];
116        } while ($i < $count);
117
118        return $output;
119    }
120
121    function gensalt_private($input)
122    {
123        $output = '$P$';
124        $output .= $this->itoa64[min($this->iteration_count_log2 + 5,
125            30)];
126        $output .= $this->encode64($input, 6);
127
128        return $output;
129    }
130
131    function crypt_private($password, $setting)
132    {
133        $output = '*0';
134        if (substr($setting, 0, 2) === $output) {
135            $output = '*1';
136        }
137
138        $id = substr($setting, 0, 3);
139        # We use "$P$", phpBB3 uses "$H$" for the same thing
140        if ($id !== '$P$' && $id !== '$H$') {
141            return $output;
142        }
143
144        $count_log2 = strpos($this->itoa64, $setting[3]);
145        if ($count_log2 < 7 || $count_log2 > 30) {
146            return $output;
147        }
148
149        $count = 1 << $count_log2;
150
151        $salt = substr($setting, 4, 8);
152        if (strlen($salt) !== 8) {
153            return $output;
154        }
155
156        # We were kind of forced to use MD5 here since it's the only
157        # cryptographic primitive that was available in all versions
158        # of PHP in use.  To implement our own low-level crypto in PHP
159        # would have resulted in much worse performance and
160        # consequently in lower iteration counts and hashes that are
161        # quicker to crack (by non-PHP code).
162        $hash = md5($salt . $password, TRUE);
163        do {
164            $hash = md5($hash . $password, TRUE);
165        } while (--$count);
166
167        $output = substr($setting, 0, 12);
168        $output .= $this->encode64($hash, 16);
169
170        return $output;
171    }
172
173    function gensalt_blowfish($input)
174    {
175        # This one needs to use a different order of characters and a
176        # different encoding scheme from the one in encode64() above.
177        # We care because the last character in our encoded string will
178        # only represent 2 bits.  While two known implementations of
179        # bcrypt will happily accept and correct a salt string which
180        # has the 4 unused bits set to non-zero, we do not want to take
181        # chances and we also do not want to waste an additional byte
182        # of entropy.
183        $itoa64 = './ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
184
185        $output = '$2a$';
186        $output .= chr((int)(ord('0') + $this->iteration_count_log2 / 10));
187        $output .= chr(ord('0') + $this->iteration_count_log2 % 10);
188        $output .= '$';
189
190        $i = 0;
191        do {
192            $c1 = ord($input[$i++]);
193            $output .= $itoa64[$c1 >> 2];
194            $c1 = ($c1 & 0x03) << 4;
195            if ($i >= 16) {
196                $output .= $itoa64[$c1];
197                break;
198            }
199
200            $c2 = ord($input[$i++]);
201            $c1 |= $c2 >> 4;
202            $output .= $itoa64[$c1];
203            $c1 = ($c2 & 0x0f) << 2;
204
205            $c2 = ord($input[$i++]);
206            $c1 |= $c2 >> 6;
207            $output .= $itoa64[$c1];
208            $output .= $itoa64[$c2 & 0x3f];
209        } while (1);
210
211        return $output;
212    }
213
214    function HashPassword($password)
215    {
216        if ( strlen( $password ) > 4096 ) {
217            return '*';
218        }
219
220        $random = '';
221
222        if (CRYPT_BLOWFISH === 1 && !$this->portable_hashes) {
223            $random = $this->get_random_bytes(16);
224            $hash =
225                crypt($password, $this->gensalt_blowfish($random));
226            if (strlen($hash) === 60) {
227                return $hash;
228            }
229        }
230
231        if (strlen($random) < 6) {
232            $random = $this->get_random_bytes(6);
233        }
234        $hash =
235            $this->crypt_private($password,
236                $this->gensalt_private($random));
237        if (strlen($hash) === 34) {
238            return $hash;
239        }
240
241        # Returning '*' on error is safe here, but would _not_ be safe
242        # in a crypt(3)-like function used _both_ for generating new
243        # hashes and for validating passwords against existing hashes.
244        return '*';
245    }
246
247    function CheckPassword($password, $stored_hash)
248    {
249        if ( strlen( $password ) > 4096 ) {
250            return false;
251        }
252
253        $hash = $this->crypt_private($password, $stored_hash);
254        if ($hash[0] === '*') {
255            $hash = crypt($password, $stored_hash);
256        }
257
258        # This is not constant-time.  In order to keep the code simple,
259        # for timing safety we currently rely on the salts being
260        # unpredictable, which they are at least in the non-fallback
261        # cases (that is, when we use /dev/urandom and bcrypt).
262        return $hash === $stored_hash;
263    }
264}
265