Encrypt password
<?php
/**
* encrypt.php
*/
$masterKey = "canyouguess";
$passwordToEncrypt = "top-secret";
//ecncypt password
$code = encrypt($masterKey, $passwordToEncrypt);
echo "code: ", $code, "\n";
/**
* @param $masterKey
* @param $password
* @return string
* @throws SodiumException
*/
function encrypt($masterKey, $password)
{
// Derive a subkey of the correct length for secretbox
$key = sodium_crypto_generichash($masterKey, '', SODIUM_CRYPTO_SECRETBOX_KEYBYTES
);
// Generate a random nonce
$nonce = random_bytes(SODIUM_CRYPTO_SECRETBOX_NONCEBYTES);
// Encrypt
$ciphertext = sodium_crypto_secretbox($password, $nonce, $key);
// Prepend nonce for later decryption, and base64-encode the lot
return base64_encode($nonce . $ciphertext);
}In the directory of encrypt.php, run:
docker run -it --rm -v "$PWD":/usr/src -w /usr/src php:8.2-cli php encrypt.phpOutput:
code: qKUilnBOnSPIOmKnwIoJAdOaC+9lhud/0eiTekLPokmuImFiRpuHvKG6AoUs7eT7fBY=Decrypt code to get password
If do not have master key, there is no way to decrypt the code
<?php
/**
* decrypt.php
*/
$masterKey = "canyouguess";
$code = "qKUilnBOnSPIOmKnwIoJAdOaC+9lhud/0eiTekLPokmuImFiRpuHvKG6AoUs7eT7fBY=";
//decrypt password using master key
$password = decrypt($masterKey, $code);
echo "password: ", $password, "\n";
/**
* @param $masterKey
* @param $code
* @return string
* @throws SodiumException
*/
function decrypt($masterKey, $code)
{
$raw = base64_decode($code, true);
if ($raw === false) {
throw new RuntimeException('Invalid base64');
}
// same derived subkey
$key = sodium_crypto_generichash($masterKey, '', SODIUM_CRYPTO_SECRETBOX_KEYBYTES
);
$nonceLen = SODIUM_CRYPTO_SECRETBOX_NONCEBYTES;
if (strlen($raw) < $nonceLen) {
throw new RuntimeException('Ciphertext too short');
}
// extract nonce and ciphertext
$nonce = mb_substr($raw, 0, $nonceLen, '8bit');
$ciphertext = mb_substr($raw, $nonceLen, null, '8bit');
// decrypt & verify
$plaintext = sodium_crypto_secretbox_open($ciphertext, $nonce, $key);
if ($plaintext === false) {
throw new RuntimeException('Decryption failed or message forged');
}
return $plaintext;
}In the same directory of decrypt.php, run:
docker run -it --rm -v "$PWD":/usr/src -w /usr/src php:8.2-cli php decrypt.phpOutput:
password: top-secret