C#과 PHP에서 같은 암호화/복호화 사용하기

1. C# 암호화 함수 

public string EncryptString(string plainText, string password)
        {
            SHA256 mySHA256 = SHA256Managed.Create();
            byte[] key = mySHA256.ComputeHash(Encoding.ASCII.GetBytes(password));
            byte[] iv = new byte[16] { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };

            // Instantiate a new Aes object to perform string symmetric encryption
            Aes encryptor = Aes.Create();
            encryptor.Mode = CipherMode.CBC;

            // Set key and IV
            byte[] aesKey = new byte[32];
            Array.Copy(key, 0, aesKey, 0, 32);
            encryptor.Key = aesKey;
            encryptor.IV = iv;

            // Instantiate a new MemoryStream object to contain the encrypted bytes
            MemoryStream memoryStream = new MemoryStream();

            // Instantiate a new encryptor from our Aes object
            ICryptoTransform aesEncryptor = encryptor.CreateEncryptor();

            // Instantiate a new CryptoStream object to process the data and write it to the 
            // memory stream
            CryptoStream cryptoStream = new CryptoStream(memoryStream, aesEncryptor, CryptoStreamMode.Write);

            // Convert the plainText string into a byte array
            byte[] plainBytes = Encoding.UTF8.GetBytes(plainText);

            // Encrypt the input plaintext string
            cryptoStream.Write(plainBytes, 0, plainBytes.Length);

            // Complete the encryption process
            cryptoStream.FlushFinalBlock();

            // Convert the encrypted data from a MemoryStream to a byte array
            byte[] cipherBytes = memoryStream.ToArray();

            // Close both the MemoryStream and the CryptoStream
            memoryStream.Close();
            cryptoStream.Close();

            // Convert the encrypted byte array to a base64 encoded string
            string cipherText = Convert.ToBase64String(cipherBytes, 0, cipherBytes.Length);

            // Return the encrypted data as a string
            return cipherText;
        }

2. C# 복호화 함수

public string DecryptString(string cipherText, string password)
        {
            SHA256 mySHA256 = SHA256Managed.Create();
            byte[] key = mySHA256.ComputeHash(Encoding.ASCII.GetBytes(password));
            byte[] iv = new byte[16] { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };

            // Instantiate a new Aes object to perform string symmetric encryption
            Aes encryptor = Aes.Create();
            encryptor.Mode = CipherMode.CBC;

            // Set key and IV
            byte[] aesKey = new byte[32];
            Array.Copy(key, 0, aesKey, 0, 32);
            encryptor.Key = aesKey;
            encryptor.IV = iv;

            // Instantiate a new MemoryStream object to contain the encrypted bytes
            MemoryStream memoryStream = new MemoryStream();

            // Instantiate a new encryptor from our Aes object
            ICryptoTransform aesDecryptor = encryptor.CreateDecryptor();

            // Instantiate a new CryptoStream object to process the data and write it to the 
            // memory stream
            CryptoStream cryptoStream = new CryptoStream(memoryStream, aesDecryptor, CryptoStreamMode.Write);

            // Will contain decrypted plaintext
            string plainText = String.Empty;

            try
            {
                // Convert the ciphertext string into a byte array
                byte[] cipherBytes = Convert.FromBase64String(cipherText);

                // Decrypt the input ciphertext string
                cryptoStream.Write(cipherBytes, 0, cipherBytes.Length);

                // Complete the decryption process
                cryptoStream.FlushFinalBlock();

                // Convert the decrypted data from a MemoryStream to a byte array
                byte[] plainBytes = memoryStream.ToArray();

                // Convert the decrypted byte array to string
                plainText = Encoding.UTF8.GetString(plainBytes, 0, plainBytes.Length);
            }
            finally
            {
                // Close both the MemoryStream and the CryptoStream
                memoryStream.Close();
                cryptoStream.Close();
            }

            // Return the decrypted data as a string
            return plainText;
        }

3. C# 확인하기

using System;
using System.IO;
using System.Security.Cryptography;

pring void test()
{
 string message = "안녕abc하하";
 string password = "12345678";
 
 string encrypted = this.EncryptString(message, password);
 string decrypted = this.DecryptString(encrypted, password);
 
 Console.WriteLine(message);
 Console.WriteLine(encrypted);
 Console.WriteLine(decrypted);
 }
 

4. PHP 암호화/복호화 하기

<?

function Encrypt($string = '', $key = '') {
	$method = 'aes-256-cbc';
	$password = substr(hash('sha256', $key, true), 0, 32);
	$iv = chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0);
	
	$encrypted = base64_encode(openssl_encrypt($string, $method, $password, OPENSSL_RAW_DATA, $iv));
	return $encrypted;
}

function Decrypt($string = '', $key = '') {
	$method = 'aes-256-cbc';
	$password = substr(hash('sha256', $key, true), 0, 32);
	$iv = chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0) . chr(0x0);
	
	$decrypted = openssl_decrypt(base64_decode($string), $method, $password, OPENSSL_RAW_DATA, $iv);
	return $decrypted;
}

?>

5. PHP 확인하기

<?

$str = "안녕abc하하";
echo "원 문자열 => " .$str. "<br />\n";

$key = '12345678';
$encrypted = Encrypt($str, $key);
echo "암호화 문자열 => " .$encrypted. "<br />\n";

$decrypted = Decrypt($encrypted, $key);
echo "복호화 문자열 => [" .$decrypted. "]";

?>