Util.php
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<?php
if (class_exists('ParagonIE_Sodium_Core_Util', false)) {
return;
}
/**
* Class ParagonIE_Sodium_Core_Util
*/
abstract class ParagonIE_Sodium_Core_Util
{
/**
* @param int $integer
* @param int $size (16, 32, 64)
* @return int
*/
public static function abs($integer, $size = 0)
{
/** @var int $realSize */
$realSize = (PHP_INT_SIZE << 3) - 1;
if ($size) {
--$size;
} else {
/** @var int $size */
$size = $realSize;
}
$negative = -(($integer >> $size) & 1);
return (int) (
($integer ^ $negative)
+
(($negative >> $realSize) & 1)
);
}
/**
* Convert a binary string into a hexadecimal string without cache-timing
* leaks
*
* @internal You should not use this directly from another application
*
* @param string $binaryString (raw binary)
* @return string
* @throws TypeError
*/
public static function bin2hex($binaryString)
{
/* Type checks: */
if (!is_string($binaryString)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($binaryString) . ' given.');
}
$hex = '';
$len = self::strlen($binaryString);
for ($i = 0; $i < $len; ++$i) {
/** @var array<int, int> $chunk */
$chunk = unpack('C', $binaryString[$i]);
/** @var int $c */
$c = $chunk[1] & 0xf;
/** @var int $b */
$b = $chunk[1] >> 4;
$hex .= pack(
'CC',
(87 + $b + ((($b - 10) >> 8) & ~38)),
(87 + $c + ((($c - 10) >> 8) & ~38))
);
}
return $hex;
}
/**
* Convert a binary string into a hexadecimal string without cache-timing
* leaks, returning uppercase letters (as per RFC 4648)
*
* @internal You should not use this directly from another application
*
* @param string $bin_string (raw binary)
* @return string
* @throws TypeError
*/
public static function bin2hexUpper($bin_string)
{
$hex = '';
$len = self::strlen($bin_string);
for ($i = 0; $i < $len; ++$i) {
/** @var array<int, int> $chunk */
$chunk = unpack('C', $bin_string[$i]);
/**
* Lower 16 bits
*
* @var int $c
*/
$c = $chunk[1] & 0xf;
/**
* Upper 16 bits
* @var int $b
*/
$b = $chunk[1] >> 4;
/**
* Use pack() and binary operators to turn the two integers
* into hexadecimal characters. We don't use chr() here, because
* it uses a lookup table internally and we want to avoid
* cache-timing side-channels.
*/
$hex .= pack(
'CC',
(55 + $b + ((($b - 10) >> 8) & ~6)),
(55 + $c + ((($c - 10) >> 8) & ~6))
);
}
return $hex;
}
/**
* Cache-timing-safe variant of ord()
*
* @internal You should not use this directly from another application
*
* @param string $chr
* @return int
* @throws SodiumException
* @throws TypeError
*/
public static function chrToInt($chr)
{
/* Type checks: */
if (!is_string($chr)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($chr) . ' given.');
}
if (self::strlen($chr) !== 1) {
throw new SodiumException('chrToInt() expects a string that is exactly 1 character long');
}
/** @var array<int, int> $chunk */
$chunk = unpack('C', $chr);
return (int) ($chunk[1]);
}
/**
* Compares two strings.
*
* @internal You should not use this directly from another application
*
* @param string $left
* @param string $right
* @param int $len
* @return int
* @throws SodiumException
* @throws TypeError
*/
public static function compare($left, $right, $len = null)
{
$leftLen = self::strlen($left);
$rightLen = self::strlen($right);
if ($len === null) {
$len = max($leftLen, $rightLen);
$left = str_pad($left, $len, "\x00", STR_PAD_RIGHT);
$right = str_pad($right, $len, "\x00", STR_PAD_RIGHT);
}
$gt = 0;
$eq = 1;
$i = $len;
while ($i !== 0) {
--$i;
$gt |= ((self::chrToInt($right[$i]) - self::chrToInt($left[$i])) >> 8) & $eq;
$eq &= ((self::chrToInt($right[$i]) ^ self::chrToInt($left[$i])) - 1) >> 8;
}
return ($gt + $gt + $eq) - 1;
}
/**
* If a variable does not match a given type, throw a TypeError.
*
* @param mixed $mixedVar
* @param string $type
* @param int $argumentIndex
* @throws TypeError
* @throws SodiumException
* @return void
*/
public static function declareScalarType(&$mixedVar = null, $type = 'void', $argumentIndex = 0)
{
if (func_num_args() === 0) {
/* Tautology, by default */
return;
}
if (func_num_args() === 1) {
throw new TypeError('Declared void, but passed a variable');
}
$realType = strtolower(gettype($mixedVar));
$type = strtolower($type);
switch ($type) {
case 'null':
if ($mixedVar !== null) {
throw new TypeError('Argument ' . $argumentIndex . ' must be null, ' . $realType . ' given.');
}
break;
case 'integer':
case 'int':
$allow = array('int', 'integer');
if (!in_array($type, $allow)) {
throw new TypeError('Argument ' . $argumentIndex . ' must be an integer, ' . $realType . ' given.');
}
$mixedVar = (int) $mixedVar;
break;
case 'boolean':
case 'bool':
$allow = array('bool', 'boolean');
if (!in_array($type, $allow)) {
throw new TypeError('Argument ' . $argumentIndex . ' must be a boolean, ' . $realType . ' given.');
}
$mixedVar = (bool) $mixedVar;
break;
case 'string':
if (!is_string($mixedVar)) {
throw new TypeError('Argument ' . $argumentIndex . ' must be a string, ' . $realType . ' given.');
}
$mixedVar = (string) $mixedVar;
break;
case 'decimal':
case 'double':
case 'float':
$allow = array('decimal', 'double', 'float');
if (!in_array($type, $allow)) {
throw new TypeError('Argument ' . $argumentIndex . ' must be a float, ' . $realType . ' given.');
}
$mixedVar = (float) $mixedVar;
break;
case 'object':
if (!is_object($mixedVar)) {
throw new TypeError('Argument ' . $argumentIndex . ' must be an object, ' . $realType . ' given.');
}
break;
case 'array':
if (!is_array($mixedVar)) {
if (is_object($mixedVar)) {
if ($mixedVar instanceof ArrayAccess) {
return;
}
}
throw new TypeError('Argument ' . $argumentIndex . ' must be an array, ' . $realType . ' given.');
}
break;
default:
throw new SodiumException('Unknown type (' . $realType .') does not match expect type (' . $type . ')');
}
}
/**
* Evaluate whether or not two strings are equal (in constant-time)
*
* @param string $left
* @param string $right
* @return bool
* @throws SodiumException
* @throws TypeError
*/
public static function hashEquals($left, $right)
{
/* Type checks: */
if (!is_string($left)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($left) . ' given.');
}
if (!is_string($right)) {
throw new TypeError('Argument 2 must be a string, ' . gettype($right) . ' given.');
}
if (is_callable('hash_equals')) {
return hash_equals($left, $right);
}
$d = 0;
/** @var int $len */
$len = self::strlen($left);
if ($len !== self::strlen($right)) {
return false;
}
for ($i = 0; $i < $len; ++$i) {
$d |= self::chrToInt($left[$i]) ^ self::chrToInt($right[$i]);
}
if ($d !== 0) {
return false;
}
return $left === $right;
}
/**
* Catch hash_update() failures and throw instead of silently proceeding
*
* @param HashContext|resource &$hs
* @param string $data
* @return void
* @throws SodiumException
* @psalm-suppress PossiblyInvalidArgument
*/
protected static function hash_update(&$hs, $data)
{
if (!hash_update($hs, $data)) {
throw new SodiumException('hash_update() failed');
}
}
/**
* Convert a hexadecimal string into a binary string without cache-timing
* leaks
*
* @internal You should not use this directly from another application
*
* @param string $hexString
* @param bool $strictPadding
* @return string (raw binary)
* @throws RangeException
* @throws TypeError
*/
public static function hex2bin($hexString, $strictPadding = false)
{
/* Type checks: */
if (!is_string($hexString)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($hexString) . ' given.');
}
/** @var int $hex_pos */
$hex_pos = 0;
/** @var string $bin */
$bin = '';
/** @var int $c_acc */
$c_acc = 0;
/** @var int $hex_len */
$hex_len = self::strlen($hexString);
/** @var int $state */
$state = 0;
if (($hex_len & 1) !== 0) {
if ($strictPadding) {
throw new RangeException(
'Expected an even number of hexadecimal characters'
);
} else {
$hexString = '0' . $hexString;
++$hex_len;
}
}
$chunk = unpack('C*', $hexString);
while ($hex_pos < $hex_len) {
++$hex_pos;
/** @var int $c */
$c = $chunk[$hex_pos];
/** @var int $c_num */
$c_num = $c ^ 48;
/** @var int $c_num0 */
$c_num0 = ($c_num - 10) >> 8;
/** @var int $c_alpha */
$c_alpha = ($c & ~32) - 55;
/** @var int $c_alpha0 */
$c_alpha0 = (($c_alpha - 10) ^ ($c_alpha - 16)) >> 8;
if (($c_num0 | $c_alpha0) === 0) {
throw new RangeException(
'hex2bin() only expects hexadecimal characters'
);
}
/** @var int $c_val */
$c_val = ($c_num0 & $c_num) | ($c_alpha & $c_alpha0);
if ($state === 0) {
$c_acc = $c_val * 16;
} else {
$bin .= pack('C', $c_acc | $c_val);
}
$state ^= 1;
}
return $bin;
}
/**
* Turn an array of integers into a string
*
* @internal You should not use this directly from another application
*
* @param array<int, int> $ints
* @return string
*/
public static function intArrayToString(array $ints)
{
/** @var array<int, int> $args */
$args = $ints;
foreach ($args as $i => $v) {
$args[$i] = (int) ($v & 0xff);
}
array_unshift($args, str_repeat('C', count($ints)));
return (string) (call_user_func_array('pack', $args));
}
/**
* Cache-timing-safe variant of ord()
*
* @internal You should not use this directly from another application
*
* @param int $int
* @return string
* @throws TypeError
*/
public static function intToChr($int)
{
return pack('C', $int);
}
/**
* Load a 3 character substring into an integer
*
* @internal You should not use this directly from another application
*
* @param string $string
* @return int
* @throws RangeException
* @throws TypeError
*/
public static function load_3($string)
{
/* Type checks: */
if (!is_string($string)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($string) . ' given.');
}
/* Input validation: */
if (self::strlen($string) < 3) {
throw new RangeException(
'String must be 3 bytes or more; ' . self::strlen($string) . ' given.'
);
}
/** @var array<int, int> $unpacked */
$unpacked = unpack('V', $string . "\0");
return (int) ($unpacked[1] & 0xffffff);
}
/**
* Load a 4 character substring into an integer
*
* @internal You should not use this directly from another application
*
* @param string $string
* @return int
* @throws RangeException
* @throws TypeError
*/
public static function load_4($string)
{
/* Type checks: */
if (!is_string($string)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($string) . ' given.');
}
/* Input validation: */
if (self::strlen($string) < 4) {
throw new RangeException(
'String must be 4 bytes or more; ' . self::strlen($string) . ' given.'
);
}
/** @var array<int, int> $unpacked */
$unpacked = unpack('V', $string);
return (int) $unpacked[1];
}
/**
* Load a 8 character substring into an integer
*
* @internal You should not use this directly from another application
*
* @param string $string
* @return int
* @throws RangeException
* @throws SodiumException
* @throws TypeError
*/
public static function load64_le($string)
{
/* Type checks: */
if (!is_string($string)) {
throw new TypeError('Argument 1 must be a string, ' . gettype($string) . ' given.');
}
/* Input validation: */
if (self::strlen($string) < 4) {
throw new RangeException(
'String must be 4 bytes or more; ' . self::strlen($string) . ' given.'
);
}
if (PHP_VERSION_ID >= 50603 && PHP_INT_SIZE === 8) {
/** @var array<int, int> $unpacked */
$unpacked = unpack('P', $string);
return (int) $unpacked[1];
}
/** @var int $result */
$result = (self::chrToInt($string[0]) & 0xff);
$result |= (self::chrToInt($string[1]) & 0xff) << 8;
$result |= (self::chrToInt($string[2]) & 0xff) << 16;
$result |= (self::chrToInt($string[3]) & 0xff) << 24;
$result |= (self::chrToInt($string[4]) & 0xff) << 32;
$result |= (self::chrToInt($string[5]) & 0xff) << 40;
$result |= (self::chrToInt($string[6]) & 0xff) << 48;
$result |= (self::chrToInt($string[7]) & 0xff) << 56;
return (int) $result;
}
/**
* @internal You should not use this directly from another application
*
* @param string $left
* @param string $right
* @return int
* @throws SodiumException
* @throws TypeError
*/
public static function memcmp($left, $right)
{
if (self::hashEquals($left, $right)) {
return 0;
}
return -1;
}
/**
* Multiply two integers in constant-time
*
* Micro-architecture timing side-channels caused by how your CPU
* implements multiplication are best prevented by never using the
* multiplication operators and ensuring that our code always takes
* the same number of operations to complete, regardless of the values
* of $a and $b.
*
* @internal You should not use this directly from another application
*
* @param int $a
* @param int $b
* @param int $size Limits the number of operations (useful for small,
* constant operands)
* @return int
*/
public static function mul($a, $b, $size = 0)
{
if (ParagonIE_Sodium_Compat::$fastMult) {
return (int) ($a * $b);
}
static $defaultSize = null;
/** @var int $defaultSize */
if (!$defaultSize) {
/** @var int $defaultSize */
$defaultSize = (PHP_INT_SIZE << 3) - 1;
}
if ($size < 1) {
/** @var int $size */
$size = $defaultSize;
}
/** @var int $size */
$c = 0;
/**
* Mask is either -1 or 0.
*
* -1 in binary looks like 0x1111 ... 1111
* 0 in binary looks like 0x0000 ... 0000
*
* @var int
*/
$mask = -(($b >> ((int) $defaultSize)) & 1);
/**
* Ensure $b is a positive integer, without creating
* a branching side-channel
*
* @var int $b
*/
$b = ($b & ~$mask) | ($mask & -$b);
/**
* Unless $size is provided:
*
* This loop always runs 32 times when PHP_INT_SIZE is 4.
* This loop always runs 64 times when PHP_INT_SIZE is 8.
*/
for ($i = $size; $i >= 0; --$i) {
$c += (int) ($a & -($b & 1));
$a <<= 1;
$b >>= 1;
}
$c = (int) @($c & -1);
/**
* If $b was negative, we then apply the same value to $c here.
* It doesn't matter much if $a was negative; the $c += above would
* have produced a negative integer to begin with. But a negative $b
* makes $b >>= 1 never return 0, so we would end up with incorrect
* results.
*
* The end result is what we'd expect from integer multiplication.
*/
return (int) (($c & ~$mask) | ($mask & -$c));
}
/**
* Convert any arbitrary numbers into two 32-bit integers that represent
* a 64-bit integer.
*
* @internal You should not use this directly from another application
*
* @param int|float $num
* @return array<int, int>
*/
public static function numericTo64BitInteger($num)
{
$high = 0;
/** @var int $low */
if (PHP_INT_SIZE === 4) {
$low = (int) $num;
} else {
$low = $num & 0xffffffff;
}
if ((+(abs($num))) >= 1) {
if ($num > 0) {
/** @var int $high */
$high = min((+(floor($num/4294967296))), 4294967295);
} else {
/** @var int $high */
$high = ~~((+(ceil(($num - (+((~~($num)))))/4294967296))));
}
}
return array((int) $high, (int) $low);
}
/**
* Store a 24-bit integer into a string, treating it as big-endian.
*
* @internal You should not use this directly from another application
*
* @param int $int
* @return string
* @throws TypeError
*/
public static function store_3($int)
{
/* Type checks: */
if (!is_int($int)) {
if (is_numeric($int)) {
$int = (int) $int;
} else {
throw new TypeError('Argument 1 must be an integer, ' . gettype($int) . ' given.');
}
}
/** @var string $packed */
$packed = pack('N', $int);
return self::substr($packed, 1, 3);
}
/**
* Store a 32-bit integer into a string, treating it as little-endian.
*
* @internal You should not use this directly from another application
*
* @param int $int
* @return string
* @throws TypeError
*/
public static function store32_le($int)
{
/* Type checks: */
if (!is_int($int)) {
if (is_numeric($int)) {
$int = (int) $int;
} else {
throw new TypeError('Argument 1 must be an integer, ' . gettype($int) . ' given.');
}
}
/** @var string $packed */
$packed = pack('V', $int);
return $packed;
}
/**
* Store a 32-bit integer into a string, treating it as big-endian.
*
* @internal You should not use this directly from another application
*
* @param int $int
* @return string
* @throws TypeError
*/
public static function store_4($int)
{
/* Type checks: */
if (!is_int($int)) {
if (is_numeric($int)) {
$int = (int) $int;
} else {
throw new TypeError('Argument 1 must be an integer, ' . gettype($int) . ' given.');
}
}
/** @var string $packed */
$packed = pack('N', $int);
return $packed;
}
/**
* Stores a 64-bit integer as an string, treating it as little-endian.
*
* @internal You should not use this directly from another application
*
* @param int $int
* @return string
* @throws TypeError
*/
public static function store64_le($int)
{
/* Type checks: */
if (!is_int($int)) {
if (is_numeric($int)) {
$int = (int) $int;
} else {
throw new TypeError('Argument 1 must be an integer, ' . gettype($int) . ' given.');
}
}
if (PHP_INT_SIZE === 8) {
if (PHP_VERSION_ID >= 50603) {
/** @var string $packed */
$packed = pack('P', $int);
return $packed;
}
return self::intToChr($int & 0xff) .
self::intToChr(($int >> 8) & 0xff) .
self::intToChr(($int >> 16) & 0xff) .
self::intToChr(($int >> 24) & 0xff) .
self::intToChr(($int >> 32) & 0xff) .
self::intToChr(($int >> 40) & 0xff) .
self::intToChr(($int >> 48) & 0xff) .
self::intToChr(($int >> 56) & 0xff);
}
if ($int > PHP_INT_MAX) {
list($hiB, $int) = self::numericTo64BitInteger($int);
} else {
$hiB = 0;
}
return
self::intToChr(($int ) & 0xff) .
self::intToChr(($int >> 8) & 0xff) .
self::intToChr(($int >> 16) & 0xff) .
self::intToChr(($int >> 24) & 0xff) .
self::intToChr($hiB & 0xff) .
self::intToChr(($hiB >> 8) & 0xff) .
self::intToChr(($hiB >> 16) & 0xff) .
self::intToChr(($hiB >> 24) & 0xff);
}
/**
* Safe string length
*
* @internal You should not use this directly from another application
*
* @ref mbstring.func_overload
*
* @param string $str
* @return int
* @throws TypeError
*/
public static function strlen($str)
{
/* Type checks: */
if (!is_string($str)) {
throw new TypeError('String expected');
}
return (int) (
self::isMbStringOverride()
? mb_strlen($str, '8bit')
: strlen($str)
);
}
/**
* Turn a string into an array of integers
*
* @internal You should not use this directly from another application
*
* @param string $string
* @return array<int, int>
* @throws TypeError
*/
public static function stringToIntArray($string)
{
if (!is_string($string)) {
throw new TypeError('String expected');
}
/**
* @var array<int, int>
*/
$values = array_values(
unpack('C*', $string)
);
return $values;
}
/**
* Safe substring
*
* @internal You should not use this directly from another application
*
* @ref mbstring.func_overload
*
* @param string $str
* @param int $start
* @param int $length
* @return string
* @throws TypeError
*/
public static function substr($str, $start = 0, $length = null)
{
/* Type checks: */
if (!is_string($str)) {
throw new TypeError('String expected');
}
if ($length === 0) {
return '';
}
if (self::isMbStringOverride()) {
if (PHP_VERSION_ID < 50400 && $length === null) {
$length = self::strlen($str);
}
$sub = (string) mb_substr($str, $start, $length, '8bit');
} elseif ($length === null) {
$sub = (string) substr($str, $start);
} else {
$sub = (string) substr($str, $start, $length);
}
if ($sub !== '') {
return $sub;
}
return '';
}
/**
* Compare a 16-character byte string in constant time.
*
* @internal You should not use this directly from another application
*
* @param string $a
* @param string $b
* @return bool
* @throws SodiumException
* @throws TypeError
*/
public static function verify_16($a, $b)
{
/* Type checks: */
if (!is_string($a)) {
throw new TypeError('String expected');
}
if (!is_string($b)) {
throw new TypeError('String expected');
}
return self::hashEquals(
self::substr($a, 0, 16),
self::substr($b, 0, 16)
);
}
/**
* Compare a 32-character byte string in constant time.
*
* @internal You should not use this directly from another application
*
* @param string $a
* @param string $b
* @return bool
* @throws SodiumException
* @throws TypeError
*/
public static function verify_32($a, $b)
{
/* Type checks: */
if (!is_string($a)) {
throw new TypeError('String expected');
}
if (!is_string($b)) {
throw new TypeError('String expected');
}
return self::hashEquals(
self::substr($a, 0, 32),
self::substr($b, 0, 32)
);
}
/**
* Calculate $a ^ $b for two strings.
*
* @internal You should not use this directly from another application
*
* @param string $a
* @param string $b
* @return string
* @throws TypeError
*/
public static function xorStrings($a, $b)
{
/* Type checks: */
if (!is_string($a)) {
throw new TypeError('Argument 1 must be a string');
}
if (!is_string($b)) {
throw new TypeError('Argument 2 must be a string');
}
return (string) ($a ^ $b);
}
/**
* Returns whether or not mbstring.func_overload is in effect.
*
* @internal You should not use this directly from another application
*
* Note: MB_OVERLOAD_STRING === 2, but we don't reference the constant
* (for nuisance-free PHP 8 support)
*
* @return bool
*/
protected static function isMbStringOverride()
{
static $mbstring = null;
if ($mbstring === null) {
if (!defined('MB_OVERLOAD_STRING')) {
$mbstring = false;
return $mbstring;
}
$mbstring = extension_loaded('mbstring')
&& defined('MB_OVERLOAD_STRING')
&&
((int) (ini_get('mbstring.func_overload')) & 2);
// MB_OVERLOAD_STRING === 2
}
/** @var bool $mbstring */
return $mbstring;
}
}