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<?php /** * http://stackoverflow.com/questions/9262109/php-simplest-two-way-encryption/30189841#30189841 * * This is not safe to use */ class UnsafeCrypto { const METHOD = 'aes-256-ctr'; /** * Encrypts (but does not authenticate) a message * * @param string $message - plaintext message * @param string $key - encryption key (raw binary expected) * @param boolean $encode - set to TRUE to return a base64-encoded * @return string (raw binary) */ public static function encrypt($message, $key, $encode = false) { $nonceSize = openssl_cipher_iv_length(self::METHOD); $nonce = openssl_random_pseudo_bytes($nonceSize); $ciphertext = openssl_encrypt( $message, self::METHOD, $key, OPENSSL_RAW_DATA, $nonce ); // Now let's pack the IV and the ciphertext together // Naively, we can just concatenate if ($encode) { return base64_encode($nonce.$ciphertext); } return $nonce.$ciphertext; } /** * Decrypts (but does not verify) a message * * @param string $message - ciphertext message * @param string $key - encryption key (raw binary expected) * @param boolean $encoded - are we expecting an encoded string? * @return string */ public static function decrypt($message, $key, $encoded = false) { if ($encoded) { $message = base64_decode($message, true); if ($message === false) { throw new Exception('Encryption failure'); } } $nonceSize = openssl_cipher_iv_length(self::METHOD); $nonce = mb_substr($message, 0, $nonceSize, '8bit'); $ciphertext = mb_substr($message, $nonceSize, null, '8bit'); $plaintext = openssl_decrypt( $ciphertext, self::METHOD, $key, OPENSSL_RAW_DATA, $nonce ); return $plaintext; } } $message = 'Ready your ammunition; we attack at dawn.'; $key = hex2bin('000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f'); $encrypted = UnsafeCrypto::encrypt($message, $key); $decrypted = UnsafeCrypto::decrypt($encrypted, $key); print_r($encrypted); //var_dump($encrypted, $decrypted);

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36.03 ms | 402 KiB | 5 Q