AndroidNDK中的C/C加密（Rijndael密码）

Question

我想把我的C#（托管）解密方法转换成Android NDK， C/C（NO JAVA）

我看到有加密。在JAVA方面，但我想远离任何JNI，我还看到有mcrypt和crypt，但找不到适用于android的编译库。

这里有一个C#的例子，我想把它翻译成C/C

    public byte[] DecryptBytes(byte[] encryptedBytes)           
    {
    RijndaelManaged RijndaelCipher = new RijndaelManaged();


            RijndaelCipher.Mode = CipherMode.CBC;

            ICryptoTransform Decryptor = RijndaelCipher.CreateDecryptor(Bytes32_KEY, Bytes16_IV);

            MemoryStream memoryStream = new MemoryStream(encryptedBytes);
            CryptoStream cryptoStream = new CryptoStream(memoryStream, Decryptor, CryptoStreamMode.Read);
            byte[] plainBytes = new byte[encryptedBytes.Length];

            int DecryptedCount = cryptoStream.Read(plainBytes, 0, plainBytes.Length);

            memoryStream.Close();
            cryptoStream.Close();

            return plainBytes;

    };

更新到目前为止，我发现最好的方法是使用openSSL AES，我已经下载了一个预编译的Android库，我只是在努力让它与一些已经发布的示例一起工作，比如c代码示例

void test_enc(){

    int keylength = 256;

    //  // 256bit KEY
        uint8_t key[32] = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
            0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
            0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F};

        //128bit IV
        uint8_t iv[16] = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F};


        //input data
        uint8_t input[64] = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07};

    size_t inputslength = 10;
    int x;

    uint8_t *aes_key = key;

    uint8_t *aes_input = input;

    uint8_t *iv_enc = iv;
    uint8_t *iv_dec = iv;

    // buffers for encryption and decryption
    const size_t encslength = ((inputslength + AES_BLOCK_SIZE) / AES_BLOCK_SIZE) * AES_BLOCK_SIZE;
    uint8_t *enc_out = (uint8_t*)malloc(sizeof(uint8_t) *encslength);
    uint8_t *dec_out = (uint8_t*)malloc(sizeof(uint8_t) *inputslength);
    memset(enc_out, 0, encslength);
    memset(dec_out, 0, inputslength);

    // so i can do with this aes-cbc-128 aes-cbc-192 aes-cbc-256
    AES_KEY enc_key, dec_key;
    AES_set_encrypt_key(aes_key, keylength, &enc_key);
    AES_cbc_encrypt(input, enc_out, inputslength, &enc_key, iv_enc, AES_ENCRYPT);

    AES_set_decrypt_key(aes_key, keylength, &dec_key);  
    AES_cbc_encrypt(enc_out, dec_out, encslength, &dec_key, iv_dec, AES_DECRYPT);

    LOGI("Before:");
    for(x=0;x<inputslength;x++)
        LOGI("%02x, ", input[x]);

    LOGI("Encrypted:");
    for(x=0;x<encslength;x++)
        LOGI("%02x, ", enc_out[x]);

    LOGI("Decrypted:");
    for(x=0;x<encslength;x++)
        LOGI("%02x, ", dec_out[x]);
};

加密的字节和c#不一样，然后解密没有返回到输入，我哪里出错了？

Answer 1

开放SSL是一个相当大的库（如果你关心APK大小）

可以在C中使用微小的AES(可以和C一起使用)

我已将其添加到Android项目（CMake）

https://github.com/anonym24/Android-Tiny-AES-NDK

Answer 2

解决了的：

问题是，在加密后，持有IV的数组似乎被更改，因此您需要在解密结果之前重置回去

使用预构建的OpenSSL for Android，您可以在这里找到OpenSSL-for-Android-pre build

上面的代码只记得在每次调用之前设置IV来AES_cbc_encrypt。