3 * A cryptographic random generator class used for generating secret keys
5 * This is based in part on Drupal code as well as what we used in our own code
6 * prior to introduction of this class.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 * http://www.gnu.org/copyleft/gpl.html
23 * @author Daniel Friesen
27 use MediaWiki\MediaWikiServices
;
31 * @deprecated since 1.32
34 protected static function singleton() {
35 wfDeprecated( __METHOD__
, '1.32' );
36 return MediaWikiServices
::getInstance()->getCryptRand();
40 * Return a boolean indicating whether or not the source used for cryptographic
41 * random bytes generation in the previously run generate* call
42 * was cryptographically strong.
44 * @deprecated since 1.32, always returns true
46 * @return bool Always true
48 public static function wasStrong() {
49 wfDeprecated( __METHOD__
, '1.32' );
54 * Generate a run of cryptographically random data and return
55 * it in raw binary form.
57 * @deprecated since 1.32, use random_bytes()
59 * @param int $bytes The number of bytes of random data to generate
60 * @return string Raw binary random data
62 public static function generate( $bytes ) {
63 wfDeprecated( __METHOD__
, '1.32' );
64 return random_bytes( floor( $bytes ) );
68 * Generate a run of cryptographically random data and return
69 * it in hexadecimal string format.
71 * @param int $chars The number of hex chars of random data to generate
72 * @return string Hexadecimal random data
74 public static function generateHex( $chars ) {
75 // hex strings are 2x the length of raw binary so we divide the length in half
76 // odd numbers will result in a .5 that leads the generate() being 1 character
77 // short, so we use ceil() to ensure that we always have enough bytes
78 $bytes = ceil( $chars / 2 );
79 // Generate the data and then convert it to a hex string
80 $hex = bin2hex( random_bytes( $bytes ) );
82 // A bit of paranoia here, the caller asked for a specific length of string
83 // here, and it's possible (eg when given an odd number) that we may actually
84 // have at least 1 char more than they asked for. Just in case they made this
85 // call intending to insert it into a database that does truncation we don't
86 // want to give them too much and end up with their database and their live
87 // code having two different values because part of what we gave them is truncated
88 // hence, we strip out any run of characters longer than what we were asked for.
89 return substr( $hex, 0, $chars );