Nathanwoodburn.github.io/libraries/Crypto.php
2021-08-30 15:06:36 +10:00

71 lines
2.0 KiB
PHP

<?php
class Astra_crypto
{
function encrypt($plainText, $key)
{
$ivsize = openssl_cipher_iv_length('AES-128-CBC');
$plainPad = $this->pkcs5_pad($plainText, $ivsize);
$secretKey = $this->hextobin(md5($key));
$initVector = pack("C*", 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f);
$ciphertext = openssl_encrypt(
$plainPad,
'AES-128-CBC',
$secretKey,
OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING,
$initVector
);
return bin2hex($ciphertext);
}
function decrypt($encryptedText, $key)
{
$secretKey = $this->hextobin(md5($key));
$initVector = pack("C*", 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f);
$encryptedText = $this->hextobin($encryptedText);
$decryptedText = openssl_decrypt(
$encryptedText,
'AES-128-CBC',
$secretKey,
OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING,
$initVector
);
$decryptedText = rtrim($decryptedText, "\0");
return $decryptedText;
}
//*********** Padding Function *********************
protected function pkcs5_pad($plainText, $blockSize)
{
$pad = $blockSize - (strlen($plainText) % $blockSize);
return $plainText . str_repeat(chr($pad), $pad);
}
//********** Hexadecimal to Binary function for php 4.0 version ********
protected function hextobin($hexString)
{
$length = strlen($hexString);
$binString = "";
$count = 0;
while ($count < $length) {
$subString = substr($hexString, $count, 2);
$packedString = pack("H*", $subString);
if ($count == 0) {
$binString = $packedString;
} else {
$binString .= $packedString;
}
$count += 2;
}
return $binString;
}
}