artabro/wire/core/WireRandom.php
2024-08-27 11:35:37 +02:00

942 lines
30 KiB
PHP
Raw Permalink Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<?php namespace ProcessWire;
/**
* Random generators for ProcessWire
*
* Includes methods for random strings, numbers, arrays and passwords.
*
* ProcessWire 3.x, Copyright 2023 by Ryan Cramer
* https://processwire.com
*
* @since 3.0.111
*
* Usage example
* ~~~~~
* $random = new WireRandom();
* $s = $random->alphanumeric(10);
* $i = $random->integer(0, 10);
* ~~~~~
*
*/
class WireRandom extends Wire {
/**
* Return random alphanumeric, alpha or numeric string
*
* This method uses cryptographically secure random generation unless you specify `true` for
* the `fast` option, in which case it will use cryptographically secure method only if PHP is
* version 7+ or the mcrypt library is available.
*
* **Note about the `allow` option:**
* If this option is used, it overrides the `alpha` and `numeric` options and creates a
* string that has only the given characters. If given characters are not ASCII alpha or
* numeric, then the `fast` option is always used, as the crypto-secure option does not
* support non-alphanumeric characters. When the `allow` option is used, the `strict`
* option does not apply.
*
* @param int $length Required length of string, or 0 for random length
* @param array $options Options to modify default behavior:
* - `alpha` (bool): Allow ASCII alphabetic characters? (default=true)
* - `upper` (bool): Allow uppercase ASCII alphabetic characters? (default=true)
* - `lower` (bool): Allow lowercase ASCII alphabetic characters? (default=true)
* - `numeric` (bool): Allow numeric characters 0123456789? (default=true)
* - `strict` (bool): Require that at least 1 character representing each true option above is present? (default=false)
* - `allow` (array|string): Only allow these ASCII alpha or digit characters, see notes. (default='')
* - `disallow` (array|string): Do not allow these characters. (default='')
* - `require` (array|string): Require that these character(s) are present. (default='')
* - `extras` (array|string): Also allow these non-alphanumeric extra characters. (default='')
* - `minLength` (int): If $length argument is 0, minimum length of returned string. (default=10)
* - `maxLength` (int): If $length argument is 0, maximum length of returned string. (default=40)
* - `noRepeat` (bool): Prevent same character from appearing more than once in sequence? (default=false)
* - `noStart` (string|array): Do not start string with these characters. (default='')
* - 'noEnd` (string|array): Do not end string with these characters. (default='')
* - `fast` (bool): Use faster method? (default=true if PHP7 or mcrypt available, false if not)
* @return string
* @throws WireException
* @since 3.0.111
*
*/
public function alphanumeric($length = 0, array $options = array()) {
$defaults = array(
'alpha' => true,
'upper' => true,
'lower' => true,
'numeric' => true,
'strict' => false,
'allow' => '',
'disallow' => array(),
'extras' => array(),
'require' => array(),
'minLength' => 10,
'maxLength' => 40,
'noRepeat' => false,
'noStart' => array(),
'noEnd' => array(),
'fast' => $this->cryptoSecure(),
);
$alphaUpperChars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
$alphaLowerChars = 'abcdefghijklmnopqrstuvwxyz';
$numericChars = '0123456789';
$options = array_merge($defaults, $options);
$allowed = '';
if($length < 1) {
$length = $this->integer($options['minLength'], $options['maxLength']);
}
// some options can be specified as strings, but we want them as arrays
foreach(array('disallow', 'extras', 'require', 'noStart', 'noEnd') as $name) {
$val = $options[$name];
if(is_array($val)) continue;
if(strlen($val)) {
$options[$name] = str_split($val);
} else {
$options[$name] = array();
}
}
// some options can be specified as arrays, but we want them as strings
foreach(array('allow', 'noStart', 'noEnd') as $name) {
if(is_array($options[$name])) $options[$name] = implode('', $options[$name]);
}
if(strlen($options['allow'])) {
// only fast option supports non-alphanumeric characters specified in allow option
if(!ctype_alnum($options['allow'])) $options['fast'] = true;
$allowed = $options['allow'];
} else {
if($options['alpha']) {
if($options['upper']) $allowed .= $alphaUpperChars;
if($options['lower']) $allowed .= $alphaLowerChars;
}
if($options['numeric']) {
$allowed .= $numericChars;
}
}
if(count($options['extras'])) {
$allowed .= implode('', $options['extras']);
}
if(count($options['disallow'])) {
$allowed = str_replace($options['disallow'], '', $allowed);
}
foreach($options['require'] as $c) {
if(strpos($allowed, $c) === false) $allowed = '';
}
if(!strlen($allowed)) {
throw new WireException("Specified options prevent any alphanumeric string from being created");
}
do {
if($options['fast']) {
$value = $this->string1($length, $allowed, $options);
} else {
$value = $this->string2($length, $allowed, $options);
}
// check that all required characters are present
if(count($options['require'])) {
$n = 0;
foreach($options['require'] as $c) {
if(strpos($value, $c) === false) $n++;
}
if($n) continue;
}
// enforce returned value having at least one of each requested type (alpha, upper, lower, numeric)
if($options['strict'] && !strlen($options['allow'])) {
if($options['alpha'] && $options['upper'] && !preg_match('/[A-Z]/', $value)) continue;
if($options['alpha'] && $options['lower'] && !preg_match('/[a-z]/', $value)) continue;
if($options['numeric'] && !preg_match('/[0-9]/', $value)) continue;
}
if(strlen($value) > $length) $value = substr($value, 0, $length);
if(strlen($options['noStart'])) $value = ltrim($value, $options['noStart']);
if(strlen($options['noEnd'])) $value = rtrim($value, $options['noEnd']);
} while(strlen($value) < $length);
return $value;
}
/**
* Generate a random string using faster method
*
* @param int $length Required length
* @param string $allowed Characters allowed
* @param array $options
* - `noRepeat` (bool): True if two of the same character may not be repeated in sequence.
* @return string
*
*/
protected function string1($length, $allowed, array $options) {
$defaults = array(
'noRepeat' => false,
);
$options = array_merge($defaults, $options);
$value = '';
$lastChar = '';
for($x = 0; $x < $length; $x++) {
$n = $this->integer(0, strlen($allowed) - 1);
$c = $allowed[$n];
if($options['noRepeat'] && $c === $lastChar) {
$x--;
continue;
}
$value .= $c;
$lastChar = $c;
}
return $value;
}
/**
* Generate random string using method that pulls from the base64 method
*
* @param int $length Required length
* @param string $allowed Allowed characters
* @param array $options See options for alphanumeric() method
*
* @return string
*
*/
protected function string2($length, $allowed, array $options) {
$defaults = array(
'extras' => array(),
'alpha' => true,
'lower' => true,
'upper' => true,
'noRepeat' => false,
);
$options = array_merge($defaults, $options);
$qty = 0;
$value = '';
$numExtras = count($options['extras']);
$base64Extras = array('slash' => '/', 'period' => '.');
do {
$baseLen = strlen($allowed) < 50 ? $length * 3 : $length * 2;
$baseStr = $this->base64($baseLen);
if($numExtras && !ctype_alnum($baseStr)) {
// base64 string includes "/" or "." characters and we have substitutions (extras)
$r = 0; // non-zero if we need to perform replacements at the ed
foreach($base64Extras as $name => $c) {
while(strpos($baseStr, $c) !== false) {
list($a, $b) = explode($c, $baseStr, 2);
$n = $numExtras > 1 ? $this->integer(0, $numExtras-1) : 0;
$x = $options['extras'][$n];
if(in_array($x, $base64Extras)) {
$x = $name;
$r++;
}
$baseStr = $a . $x . $b;
}
}
if($r) {
// replacements necessary
$baseStr = str_replace(array_keys($base64Extras), array_values($base64Extras), $baseStr);
}
unset($a, $b, $c, $r, $x);
}
if($options['alpha']) {
if($options['lower'] && !$options['upper']) {
$baseStr = strtolower($baseStr);
} else if($options['upper'] && !$options['lower']) {
$baseStr = strtoupper($baseStr);
}
}
$lastChar = '';
for($n = 0; $n < strlen($baseStr); $n++) {
$c = $baseStr[$n];
if(strpos($allowed, $c) === false) continue;
if($options['noRepeat'] && $c === $lastChar) continue;
$value .= $c;
$lastChar = $c;
if(++$qty >= $length) break;
}
} while($qty < $length);
return $value;
}
/**
* Return string of random ASCII alphabetical letters
*
* @param int $length Required length of string or 0 for random length
* @param array $options See options for alphanumeric() method
* @return string
* @since 3.0.111
*
*/
public function alpha($length = 0, array $options = array()) {
if(!isset($options['numeric'])) $options['numeric'] = false;
return $this->alphanumeric($length, $options);
}
/**
* Return string of random numbers/digits
*
* @param int $length Required length of string or 0 for random length
* @param array $options See options for alphanumeric() method
* @return string
* @since 3.0.111
*
*/
public function numeric($length = 0, array $options = array()) {
$options['alpha'] = false;
return $this->alphanumeric($length, $options);
}
/**
* Get a random integer
*
* @param int $min Minimum allowed value (default=0).
* @param int $max Maximum allowed value (default=PHP_INT_MAX).
* @param array $options
* - `info` (bool): Return array of [value, type] indicating what type of random generator was used? (default=false).
* - `cryptoSecure` (bool): Throw WireException if cryptographically secure type not available (default=false).
* @return int|array Returns integer, or will return array if $info option specified.
* @throws WireException
*
*/
public function integer($min = 0, $max = PHP_INT_MAX, array $options = array()) {
$defaults = array(
'info' => false,
'cryptoSecure' => false,
);
if(is_array($min)) {
$options = $min;
$min = isset($options['min']) ? (int) $options['min'] : 0;
} else if(is_array($max)) {
$options = $max;
$max = isset($options['max']) ? (int) $options['max'] : PHP_INT_MAX;
}
$options = array_merge($defaults, $options);
if($max == $min) return $max;
if($max < $min) throw new WireException('Max may not be less than min');
if(function_exists('random_int')) {
// PHP 7 has random_int, previous versions do not
$value = random_int($min, $max);
$type = 'random_int';
} else if(function_exists('mcrypt_create_iv')) {
// via user contributed notes at: http://php.net/manual/en/function.random-int.php
$range = $counter = $max - $min;
$bits = 1;
while($counter >>= 1) ++$bits;
$bytes = (int) max(ceil($bits / 8), 1);
$bitmask = pow(2, $bits) - 1;
if($bitmask >= PHP_INT_MAX) $bitmask = PHP_INT_MAX;
do {
$result = hexdec(bin2hex(mcrypt_create_iv($bytes, MCRYPT_DEV_URANDOM))) & $bitmask;
} while($result > $range);
$value = $result + $min;
$type = 'mcrypt';
} else if($options['cryptoSecure']) {
throw new WireException('cryptoSecure required and neither PHP7 random_int() or mcrypt available');
} else {
// mt_rand (not cryptographically secure)
$value = mt_rand($min, $max);
$type = 'mt_rand';
}
if($options['info']) return array($value, $type);
return $value;
}
/**
* Get a random item (or items, key or keys) from the given array
*
* - Given array may be regular or associative.
*
* - If given a `qty` other than 1 (default) then the `getArray` option is assumed true, unless a
* different value for the `getArray` option was manually specified.
*
* - When using the `getArray` option, returned array will have keys retained, except when `qty`
* option exceeds the number of items in given array `$a`, then keys will not be retained.
*
* @param array $a Array to get random item from
* @param array $options Options to modify behavior:
* - `qty` (int): Return this quantity of item(s) (default=1).
* - `getKey` (bool): Return item key(s) rather than values.
* - `getArray` (bool): Return array (with original keys) rather than value (default=false if qty==1, true if not).
* @return mixed|array|null
*
*/
protected function arrayItem(array $a, array $options = array()) {
$defaults = array(
'qty' => 1,
'getKey' => false,
'getArray' => null, // null=not specified
);
$options = array_merge($defaults, $options);
$count = count($a);
$keys = array_keys($a);
$items = array();
$keepKeys = true;
// if getArray option not specified, auto determine from qty
if($options['getArray'] === null) {
$options['getArray'] = $options['qty'] === 1 ? false : true;
}
// if given an empty array, return an empty value
if(!$count) return $options['getArray'] ? array() : null;
// if impossible qty requested, adjust according to what is present
if($options['qty'] < 1) $options['qty'] = $count;
do {
$keysIndex = $this->integer(0, count($keys) - 1);
$key = $keys[$keysIndex];
$item = $options['getKey'] ? $key : $a[$key];
if($keepKeys) {
// if getting more than one item, ensure its not the same one we already got
if(array_key_exists($key, $items)) continue;
$items[$key] = $item;
} else {
// they are requesting a quantity larger than whats in the array, so disregard keys or duplicates
$items[] = $item;
}
// if more items requested than in original array, and weve got all of them, stop keeping track of keys
if($options['qty'] > $count && count($items) === $count) {
$keepKeys = false;
$items = array_values($items);
}
} while(count($items) < $options['qty']);
if($options['getArray']) {
// if requesting a qty greater than whats in array, the first $count items will be unique
// so run them through a shuffle() to prevent that predictable behavior
if($options['qty'] > $count) shuffle($items);
return $items;
} else {
return $item;
}
}
/**
* Get a random value from given array
*
* @param array $a Array to get random value from
* @return mixed|null
*
*/
public function arrayValue(array $a) {
return $this->arrayItem($a);
}
/**
* Return a random version of given array or a quantity of random items
*
* Array keys are retained in return value, unless requested $qty exceeds
* the quantity of items in given array.
*
* @param array $a Array to get random items from.
* @param int $qty Quantity of items, or 0 to return all (default=0).
* @return array
*
*/
public function arrayValues(array $a, $qty = 0) {
return $this->arrayItem($a, array('getArray' => true, 'qty' => $qty));
}
/**
* Get a random key from given array
*
* @param array $a
* @return string|int
*
*/
public function arrayKey(array $a) {
return $this->arrayItem($a, array('getKey' => true));
}
/**
* Get a random version of all keys in given array (or a specified quantity of them)
*
* @param array $a Array to get random keys from.
* @param int $qty Quantity of unique keys to return or 0 for all (default=0)
* @return array
*
*/
public function arrayKeys(array $a, $qty = 0) {
return $this->arrayItem($a, array('getKey' => true, 'getArray' => true, 'qty' => $qty));
}
/**
* Shuffle a string or an array
*
* Unlike PHPs shuffle() function, this method:
*
* - Accepts strings or arrays and returns the same type.
* - Maintains array keys, if given an array.
* - Returns a copy of the value rather than modifying the given value directly.
* - Is cryptographically secure if PHP7 or mcrypt available.
*
* @param string|array $value
* @return string|array
*
*/
public function shuffle($value) {
$isArray = is_array($value);
if(!$isArray) {
if(function_exists('mb_substr')) {
$a = array();
for($n = 0; $n < mb_strlen($value); $n++) {
$c = mb_substr($value, $n, 1);
$a[] = $c;
}
$value = $a;
} else {
$value = str_split((string) $value);
}
}
$value = $this->arrayValues($value);
if(!$isArray) $value = implode('', $value);
return $value;
}
/**
* Generate and return a random password
*
* Default settings of this method are to generate a random but readable password without characters that
* tend to have readability issues, and using only ASCII characters (for broadest keyboard compatibility).
*
* @param array $options Specify any of the following options (all optional):
* - `minLength` (int): Minimum lenth of returned value (default=7).
* - `maxLength` (int): Maximum lenth of returned value, will be exceeded if needed to meet other options (default=15).
* - `minLower` (int): Minimum number of lowercase characters required (default=1).
* - `minUpper` (int): Minimum number of uppercase characters required (default=1).
* - `maxUpper` (int): Maximum number of uppercase characters allowed (0=any, -1=none, default=3).
* - `minDigits` (int): Minimum number of digits required (default=1).
* - `maxDigits` (int): Maximum number of digits allowed (0=any, -1=none, default=0).
* - `minSymbols` (int): Minimum number of non-alpha, non-digit symbols required (default=0).
* - `maxSymbols` (int): Maximum number of non-alpha, non-digit symbols to allow (0=any, -1=none, default=3).
* - `useSymbols` (array): Array of characters to use as "symbols" in returned value (see method for default).
* - `disallow` (array): Disallowed characters that may be confused with others (default=O,0,I,1,l).
*
* @return string
*
*/
public function pass(array $options = array()) {
$defaults = array(
'minLength' => 7,
'maxLength' => 15,
'minUpper' => 1,
'maxUpper' => 3,
'minLower' => 1,
'minDigits' => 1,
'maxDigits' => 0,
'minSymbols' => 0,
'maxSymbols' => 3,
'useSymbols' => array('@', '#', '$', '%', '^', '*', '_', '-', '+', '?', '(', ')', '!', '.', '=', '/'),
'disallow' => array('O', '0', 'I', '1', 'l'),
);
$options = array_merge($defaults, $options);
// check if we need to increase maxLength to accommodate given options
$minLength = $options['minUpper'] + $options['minLower'] + $options['minDigits'] + $options['minSymbols'];
if($minLength > $options['maxLength']) $options['maxLength'] = $minLength;
$value = $this->passCreate($options);
if(strlen($value) > $options['maxLength']) $value = $this->passTrunc($value, $options);
return $value;
}
/**
* Create a password (for password method)
*
* @param array $options
* @return string
*
*/
protected function passCreate(array $options) {
$length = $this->integer($options['minLength'], $options['maxLength']);
$base64Symbols = array('/' , '.');
$disallow = $options['disallow'];
$disallowCase = array(); // with both upper and lower versions
foreach($disallow as $c) {
$c = strtolower($c);
$disallowCase[$c] = $c;
$c = strtoupper($c);
$disallowCase[$c] = $c;
}
// build foundation of password using base64 string
do {
$value = $this->base64($length);
$valid = preg_match('/[A-Z]/i', $value) && preg_match('/[0-9]/', $value);
} while(!$valid);
// limit amount of characters that are too common in base64 string
foreach($base64Symbols as $char) {
do {
$pos = strpos($value, $char);
if($pos === false) break;
$value[$pos] = $this->alphanumeric(1, array('disallow' => $disallow));
} while(1);
}
// manage quantity of symbols
if($options['maxSymbols'] > -1) {
// ensure there are a certain quantity of symbols present
if($options['maxSymbols'] === 0) {
$numSymbols = $this->integer($options['minSymbols'], floor(strlen($value) / 2));
} else {
$numSymbols = $this->integer($options['minSymbols'], $options['maxSymbols']);
}
$symbols = $options['useSymbols'];
shuffle($symbols);
for($n = 0; $n < $numSymbols; $n++) {
$symbol = array_shift($symbols);
$value .= $symbol;
}
} else {
// no symbols, remove those commonly added in base64 string
foreach($base64Symbols as $char) {
$disallow[] = $char;
$disallowCase[$char] = $char;
}
}
// manage quantity of uppercase characters
if($options['maxUpper'] > 0 || ($options['minUpper'] > 0 && $options['maxUpper'] > -1)) {
// limit or establish the number of uppercase characters
if(!$options['maxUpper']) $options['maxUpper'] = floor(strlen($value) / 2);
$numUpper = $this->integer($options['minUpper'], $options['maxUpper']);
if($numUpper) {
$value = strtolower($value);
$test = $this->wire()->sanitizer->alpha($value);
if(strlen($test) < $numUpper) {
// there aren't enough characters present to meet requirements, so add some
$value .= $this->alpha($numUpper - strlen($test), array('disallow' => $disallow));
}
for($i = 0; $i < strlen($value); $i++) {
$c = strtoupper($value[$i]);
if(in_array($c, $disallow)) continue;
if($c !== $value[$i]) $value[$i] = $c;
if($c >= 'A' && $c <= 'Z') $numUpper--;
if(!$numUpper) break;
}
// still need more? append new characters as needed
if($numUpper) $value .= strtoupper($this->alpha($numUpper, array('disallow' => $disallowCase)));
}
} else if($options['maxUpper'] < 0) {
// disallow upper
$value = strtolower($value);
}
// manage quantity of lowercase characters
if($options['minLower'] > 0) {
$test = preg_replace('/[^a-z]/', '', $value);
if(strlen($test) < $options['minLower']) {
// needs more lowercase
$value .= strtolower($this->alpha($options['minLower'] - strlen($test), array('disallow' => $disallowCase)));
}
}
// manage quantity of required digits
if($options['minDigits'] > 0) {
$test = $this->wire()->sanitizer->digits($value);
$test = str_replace($options['disallow'], '', $test);
$numDigits = $options['minDigits'] - strlen($test);
if($numDigits > 0) {
$value .= $this->numeric($numDigits, array('disallow' => $disallow));
}
}
if($options['maxDigits'] > 0 || $options['maxDigits'] == -1) {
// a maximum number of digits specified
$numDigits = 0;
for($n = 0; $n < strlen($value); $n++) {
$c = $value[$n];
$isDigit = ctype_digit($c);
if($isDigit) $numDigits++;
if($isDigit && $numDigits > $options['maxDigits']) {
// convert digit to alpha
$value[$n] = strtolower($this->alpha(1, array('disallow' => $disallowCase)));
}
}
}
// replace any disallowed characters
foreach($disallow as $char) {
$n = 0;
do {
$pos = strpos($value, $char);
if($pos === false) break;
if(ctype_digit($char)) {
// find a different digit
$c = $this->numeric(1, array('disallow' => $disallow));
} else if(strtoupper($char) === $char) {
// find a different uppercase char
$c = strtoupper($this->alpha(1, array('disallow' => $disallowCase)));
} else {
// find a different lowercase char
$c = strtolower($this->alpha(1, array('disallow' => $disallowCase)));
}
while(in_array($c, $disallow)) {
// insurance fallback, not likely (impossible?) to occur
$c = $this->alphanumeric(1);
}
$value[$pos] = $c;
} while(++$n < 100);
}
// randomize, in case any operations above need it
$value = $this->shuffle($value);
return $value;
}
/**
* Truncate password to requested maxLength without removing required options (for password method)
*
* @param string $value
* @param array $options See options from password() method
* @return string
*
*/
protected function passTrunc($value, array $options) {
$chars = array(
'minLower' => array(),
'minUpper' => array(),
'minDigits' => array(),
'minSymbols' => array(),
);
$value = str_split($value);
for($n = 0; $n < count($value); $n++) {
$c = $value[$n];
if($c >= 'a' && $c <= 'z') {
$chars['minLower'][$n] = $c;
} else if($c >= 'A' && $c <= 'Z') {
$chars['minUpper'][$n] = $c;
} else if($c >= '0' && $c <= '9') {
$chars['minDigits'][$n] = $c;
} else if(in_array($c, $options['useSymbols'])) {
$chars['minSymbols'][$n] = $c;
}
}
$cnt = 0;
$max = 100;
while(count($value) > $options['maxLength'] && ++$cnt <= $max) {
$key = $this->arrayKey($chars);
if(count($chars[$key]) > $options[$key]) {
$n = $this->arrayKey($chars[$key]);
unset($chars[$key][$n]);
unset($value[$n]);
}
}
if($cnt >= $max) {
// impossible to accommodate length request with given options
}
return implode('', $value);
}
/**
* Generate a truly random base64 string of a certain length
*
* This is largely taken from Anthony Ferrara's password_compat library:
* https://github.com/ircmaxell/password_compat/blob/master/lib/password.php
* Modified for camelCase, variable names, and function-based context by Ryan.
*
* @param int $requiredLength Length of string you want returned (default=22)
* @param array|bool $options Specify array of options or boolean to specify only `fast` option.
* - `fast` (bool): Use fastest, not cryptographically secure method (default=false).
* - `test` (bool|array): Return tests in a string (bool true), or specify array(true) to return tests array (default=false).
* Note that if the test option is used, then the fast option is disabled.
* @return string|array Returns only array if you specify array for $test argument, otherwise returns string
*
*/
public function base64($requiredLength = 22, $options = array()) {
$defaults = array(
'fast' => false,
'test' => false,
);
if(is_array($options)) {
$options = array_merge($defaults, $options);
} else {
if(is_bool($options)) $defaults['fast'] = $options;
$options = $defaults;
}
$buffer = '';
$valid = false;
$tests = array();
$test = $options['test'];
if($options['fast'] && !$test) {
// fast mode for non-password use, uses only mt_rand() generated characters
$rawLength = $requiredLength;
} else {
// for password use, slower
$rawLength = (int) ($requiredLength * 3 / 4 + 1);
// PHP7 random_bytes
if((!$valid || $test) && function_exists('random_bytes')) {
try {
$buffer = random_bytes($rawLength);
if($buffer) $valid = true;
} catch(\Exception $e) {
$valid = false;
}
if($test) $tests['random_bytes'] = $buffer;
} else if($test) {
$tests['random_bytes'] = '';
}
// mcrypt_create_iv
if((!$valid || $test) && function_exists('mcrypt_create_iv') && !defined('PHALANGER')) {
// @operator added for PHP 7.1 which throws deprecated notice on this function call
$buffer = @mcrypt_create_iv($rawLength, MCRYPT_DEV_URANDOM);
if($buffer) $valid = true;
if($test) $tests['mcrypt_create_iv'] = $buffer;
} else if($test) {
$tests['mcrypt_create_iv'] = '';
}
// openssl_random_pseudo_bytes
if((!$valid || $test) && function_exists('openssl_random_pseudo_bytes')) {
$good = false;
$buffer = openssl_random_pseudo_bytes($rawLength, $good);
if($test) $tests['openssl_random_pseudo_bytes'] = $buffer . "\tNOTE=" . ($good ? 'strong' : 'NOT strong');
if(!$good) $buffer = '';
if($buffer) $valid = true;
} else if($test) {
$tests['openssl_random_pseudo_bytes'] = '';
}
// read from /dev/urandom
if((!$valid || $test) && @is_readable('/dev/urandom')) {
$f = fopen('/dev/urandom', 'r');
$readLength = 0;
if($test) $buffer = '';
while($readLength < $rawLength) {
$buffer .= fread($f, $rawLength - $readLength);
$readLength = $this->_strlen($buffer);
}
fclose($f);
if($readLength >= $rawLength) $valid = true;
if($test) $tests['/dev/urandom'] = $buffer;
} else if($test) {
$tests['/dev/urandom'] = '';
}
}
$bufferLength = $this->_strlen($buffer);
// randomInteger or mt_rand() fast
if(!$valid || $test || $bufferLength < $rawLength) {
for($i = 0; $i < $rawLength; $i++) {
if($i < $bufferLength) {
$buffer[$i] = $buffer[$i] ^ chr($this->integer(0, 255));
} else {
$buffer .= chr($this->integer(0, 255));
}
}
if($test) $tests['randomInteger'] = $buffer;
}
if($test) {
// test mode
$salt = '';
foreach($tests as $name => $value) {
$note = '';
if(strpos($value, "\tNOTE=")) list($value, $note) = explode("\tNOTE=", $value);
$value = empty($value) ? 'N/A' : $this->randomBufferToSalt($value, $requiredLength);
$_name = str_pad($name, 28, ' ', STR_PAD_LEFT);
$tests[$name] = $value;
$salt .= "\n$_name: $value $note";
}
$salt = is_array($test) ? $tests : ltrim($salt, "\n");
} else {
// regular random string mode
$salt = $this->randomBufferToSalt($buffer, $requiredLength);
}
return $salt;
}
/**
* Given random buffer string of bytes return base64 encoded salt
*
* @param string $buffer
* @param int $requiredLength
* @return string
*
*/
protected function randomBufferToSalt($buffer, $requiredLength) {
$c1 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'; // base64
$c2 = './ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'; // bcrypt64
$salt = rtrim(base64_encode($buffer), '=');
$salt = strtr($salt, $c1, $c2);
$salt = substr($salt, 0, $requiredLength);
return $salt;
}
/**
* Is a crypto secure method of generating numbers available?
*
* @return bool
*
*/
public function cryptoSecure() {
return function_exists('random_int') || function_exists('mcrypt_create_iv');
}
/**
* Return string length, using mb_strlen() when available, or strlen() when not
*
* @param string $s
* @return int
*
*/
protected function _strlen($s) {
return function_exists('mb_strlen') ? mb_strlen($s, '8bit') : strlen($s);
}
}