ParagonIE_Sodium_Core_Base64_UrlSafe::decode() public WP 1.0
decode from base64 into binary
Base64 character set "./[A-Z][a-z][0-9]"
{} It's a method of the class: ParagonIE_Sodium_Core_Base64_UrlSafe{}
No Hooks.
Return
String
. Null. Nothing.
Usage
$result = ParagonIE_Sodium_Core_Base64_UrlSafe::decode( $src, $strictPadding );
- $src(string) (required)
- -
$strictPadding *(true | false)* |
---|
Code of ParagonIE_Sodium_Core_Base64_UrlSafe::decode() ParagonIE Sodium Core Base64 UrlSafe::decode WP 5.7
public static function decode($src, $strictPadding = false)
{
// Remove padding
$srcLen = ParagonIE_Sodium_Core_Util::strlen($src);
if ($srcLen === 0) {
return '';
}
if ($strictPadding) {
if (($srcLen & 3) === 0) {
if ($src[$srcLen - 1] === '=') {
$srcLen--;
if ($src[$srcLen - 1] === '=') {
$srcLen--;
}
}
}
if (($srcLen & 3) === 1) {
throw new RangeException(
'Incorrect padding'
);
}
if ($src[$srcLen - 1] === '=') {
throw new RangeException(
'Incorrect padding'
);
}
} else {
$src = rtrim($src, '=');
$srcLen = ParagonIE_Sodium_Core_Util::strlen($src);
}
$err = 0;
$dest = '';
// Main loop (no padding):
for ($i = 0; $i + 4 <= $srcLen; $i += 4) {
/** @var array<int, int> $chunk */
$chunk = unpack('C*', ParagonIE_Sodium_Core_Util::substr($src, $i, 4));
$c0 = self::decode6Bits($chunk[1]);
$c1 = self::decode6Bits($chunk[2]);
$c2 = self::decode6Bits($chunk[3]);
$c3 = self::decode6Bits($chunk[4]);
$dest .= pack(
'CCC',
((($c0 << 2) | ($c1 >> 4)) & 0xff),
((($c1 << 4) | ($c2 >> 2)) & 0xff),
((($c2 << 6) | $c3) & 0xff)
);
$err |= ($c0 | $c1 | $c2 | $c3) >> 8;
}
// The last chunk, which may have padding:
if ($i < $srcLen) {
/** @var array<int, int> $chunk */
$chunk = unpack('C*', ParagonIE_Sodium_Core_Util::substr($src, $i, $srcLen - $i));
$c0 = self::decode6Bits($chunk[1]);
if ($i + 2 < $srcLen) {
$c1 = self::decode6Bits($chunk[2]);
$c2 = self::decode6Bits($chunk[3]);
$dest .= pack(
'CC',
((($c0 << 2) | ($c1 >> 4)) & 0xff),
((($c1 << 4) | ($c2 >> 2)) & 0xff)
);
$err |= ($c0 | $c1 | $c2) >> 8;
} elseif ($i + 1 < $srcLen) {
$c1 = self::decode6Bits($chunk[2]);
$dest .= pack(
'C',
((($c0 << 2) | ($c1 >> 4)) & 0xff)
);
$err |= ($c0 | $c1) >> 8;
} elseif ($i < $srcLen && $strictPadding) {
$err |= 1;
}
}
/** @var bool $check */
$check = ($err === 0);
if (!$check) {
throw new RangeException(
'Base64::decode() only expects characters in the correct base64 alphabet'
);
}
return $dest;
}