blackberry - BouncyCaSTLe J2ME RSA 使用自定义 key

Question

我想在我的黑莓应用程序中使用 BouncyCaSTLe J2ME/RIM Crypto。

我遇到的问题是我想从 C#.NET 程序生成用于加密的公钥，该程序将 key 发送到 BlackBerry。

是否可以使用原始字符串加密消息？另外，我是否需要知道其他常见变量，例如模数等？抱歉，我对密码算法完全陌生。

为此我需要 BouncyCaSTLe 还是可以使用 RIM Crypto 完成上述操作？

谢谢，康纳

Answer 1

我是使用 bouncycaSTLe 完成的，但与 RIM Crypto 类似。根据例子。如您所见，键是字符串...:

    public CypherDecypherExample()
   {        
    String plain    ="a plain string";
    String cipher   = null;
    String decipher = null;
    byte [] byte_cipher = null;
    byte [] byte_plain  = null;

    // key           |-- 128 bit -->|-- 256 bit --->|
    String key    = "aaaaaaaaaaaaaaaacccccccccccccccc";
    String iv     = "bbbbbbbbbbbbbbbb";

System.out.println("bouncycastle.plain: " + plain);

    try {
        byte_cipher = encrypt(plain.getBytes(), key.getBytes(), iv.getBytes());
        cipher = new String(byte_cipher);
        System.out.println("bouncycastle.cipher: " + cipher);

    } catch (Exception e) {
        e.printStackTrace();
    }


    try {
        byte_plain = decrypt(byte_cipher, key.getBytes(), iv.getBytes());
        decipher = new String(byte_plain);
        System.out.println("bouncycastle.decipher: " + decipher);
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

} 

private static byte[] cipherData(PaddedBufferedBlockCipher cipher, byte[] data)
throws Exception
{
    String plain = new String(data);
    System.out.println("bouncycastle.cipherData: " + plain);

    int minSize = cipher.getOutputSize(data.length);
    byte[] outBuf = new byte[minSize];
    int length1 = cipher.processBytes(data, 0, data.length, outBuf, 0);
    int length2 = cipher.doFinal(outBuf, length1);
    int actualLength = length1 + length2;
    byte[] result = new byte[actualLength];
    System.arraycopy(outBuf, 0, result, 0, result.length);

System.out.println("bouncycastle.cipherData returning");

    return result;
}

private static byte[] decrypt(byte[] cipher, byte[] key, byte[] iv) throws Exception
{
    PaddedBufferedBlockCipher aes = new PaddedBufferedBlockCipher((BlockCipher) new CBCBlockCipher(
            new AESEngine()));
    CipherParameters ivAndKey = new ParametersWithIV(new KeyParameter(key), iv);
    aes.init(false, ivAndKey);
    return cipherData(aes, cipher);
}

private static byte[] encrypt(byte[] plain, byte[] key, byte[] iv) throws Exception
{       
    PaddedBufferedBlockCipher aes = new PaddedBufferedBlockCipher(new CBCBlockCipher(
            new AESEngine()));

    CipherParameters ivAndKey = new ParametersWithIV(new KeyParameter(key), iv);

    aes.init(true, ivAndKey);

    return cipherData(aes, plain);
}