c# - AES 加密/解密 - 动态 C 到 C#

Question

我正在使用 Dynamic C Rabbit 微处理器上的编程语言。我相信 Dynamic C 是基于 ANSI-C89 的，只是做了一些非常细微的改动。他们有一个 AES 加密库，我试图在将数据发送到我的服务器之前使用它来加密数据(但收效甚微)。

这是我正在使用的基于 C 的 AES 函数的文档:

AESinitStream

SYNTAX: void AESinitStream(AESstreamState *state, const char *key, const char *init_vector);

DESCRIPTION: Sets up a stream state structure to begin encrypting or decrypting a stream. A particular stream state can only be used for one direction.

PARAMETER1: state - An AESstreamState structure to be initialized

PARAMETER2: key - the 16-byte cipher key, using a NULL pointer will prevent an existing key from being recalculated.

PARAMETER3: init_vector - a 16-byte array representing the initial state of the feedback registers. Both ends of the stream must begin with the same initialization vector and key.

AESencryptStream

SYNTAX: void AESencryptStream(AESstreamState *state, char *data, int count);

DESCRIPTION: Encrypts an array of bytes

PARAMETER1: state - The AESstreamState structure

PARAMETER2: data - an array of bytes that will be encrypted in place.

PARAMETER3: count - size of data array

这是我的 C 代码:

    const char key[] = {'\x41', '\x41', '\x37', '\x44',
                        '\x44', '\x34', '\x30', '\x33',
                        '\x30', '\x35', '\x39', '\x4e',
                        '\x36', '\x37', '\x30', '\x38'};
    AESstreamState encrypt_state; //built in Dynamic C type
    char init_vector[16];
    int i;
    int bufLength;

    sprintf(Buf, "%s", "testabc");
    bufLength = strlen(Buf);

    for (i = 0; i < 16; i++)
        init_vector[i] = rand() % 255;

    printf("Key: ");
    for (i = 0; i < sizeof(key); i++)
        printf("%d ", key[i]);
    printf("\n");

    AESinitStream(&encrypt_state, key, init_vector);  //built in Dynamic C function
    AESencryptStream(&encrypt_state, Buf, bufLength); //built in Dynamic C function

    printf("Data: ");
    for (i = 0; i < strlen(Buf); i++)
        printf("%d ", Buf[i]);
    printf("\n");

    //set first byte to something that lets the server know it's encrypted
    //set 2nd through 16th byte to the IV (initialization vector) so every message will be different even if they have the same contents
    for (i = bufLength-1; i >= 0; i--)
        Buf[i+17] = Buf[i];
    Buf[0] = 237; //φ

    printf("IV: ");
    for (i = 1; i < 17; i++)
    {
        printf("%d ", init_vector[i-1]);
        Buf[i] = init_vector[i-1];
    }
    printf("\n");

输出:

Key: 65 65 55 68 68 52 48 51 48 53 57 78 54 55 48 56

Data: 249 78 60 83 130 167 37

IV: 74 121 108 165 83 120 36 27 161 192 84 76 105 239 34 214

这是我的 C# 代码:

    private string DecryptAES(byte[] cipherText, byte[] IV)
    {
        byte[] key = {
            0x41, 0x41, 0x37, 0x44,
            0x44, 0x34, 0x30, 0x33,
            0x30, 0x35, 0x39, 0x4e,
            0x36, 0x37, 0x30, 0x38
        };

        // Check arguments.
        if (cipherText == null || cipherText.Length <= 0)
        {
            throw new ArgumentNullException("cipherText");
        }
        else if (IV == null || IV.Length <= 0 || IV.Length != 16)
        {
            throw new ArgumentNullException("IV");
        }

        Console.Write("Key: ");
        for (int i = 0; i < key.Length; i++)
            Console.Write("{0} ", key[i]);
        Console.WriteLine();

        Console.Write("Data: ");
        for (int i = 0; i < cipherText.Length; i++)
            Console.Write("{0} ", cipherText[i]);
        Console.WriteLine();

        Console.Write("IV: ");
        for (int i = 0; i < IV.Length; i++)
            Console.Write("{0} ", IV[i]);
        Console.WriteLine();

        // Create an RijndaelManaged object
        // with the specified key and IV.
        using (RijndaelManaged rijAlg = new RijndaelManaged())
        {
            rijAlg.Mode = CipherMode.CFB;
            rijAlg.FeedbackSize = 8;
            rijAlg.BlockSize = 128;
            rijAlg.Padding = PaddingMode.None;

            rijAlg.Key = key;
            rijAlg.IV = IV;

            // Create a decrytor to perform the stream transform.
            ICryptoTransform decryptor = rijAlg.CreateDecryptor(rijAlg.Key, rijAlg.IV);

            // Create the streams used for decryption.
            using (System.IO.MemoryStream msDecrypt = new System.IO.MemoryStream(cipherText))
            {
                using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                {
                    using (System.IO.StreamReader srDecrypt = new System.IO.StreamReader(csDecrypt))
                    {
                        // Read the decrypted bytes from the decrypting stream
                        // and place them in a string.
                        string plaintext = null;

                        plaintext = srDecrypt.ReadToEnd();

                        Console.WriteLine("Decrypted: " + plaintext);

                        return plaintext;
                    }
                }

            }
        }
    }

输出:

Key: 65 65 55 68 68 52 48 51 48 53 57 78 54 55 48 56

Data: 249 78 60 83 130 167 37

IV: 74 121 108 165 83 120 36 27 161 192 84 76 105 239 34 214

Decrypted: t{^^?d2

如您所见，我在解密的文本中得到了一些奇怪的输出。有人能指出我正确的方向吗？

我曾尝试使用 Dynamic C 成功解密它，但如果您认为内置的 Dynamic C AES 库是罪魁祸首，您会推荐什么？

编辑:所以我决定使用 C# 的 AES 库对其进行加密并获得不同的密码:

    private byte[] EncryptStringToBytes(string plainText, byte[] Key, byte[] IV)
    {
        // Check arguments.
        if (plainText == null || plainText.Length <= 0)
        {
            throw new ArgumentNullException("plainText");
        }
        if (Key == null || Key.Length <= 0)
        {
            throw new ArgumentNullException("Key");
        }
        if (IV == null || IV.Length <= 0)
        {
            throw new ArgumentNullException("IV");
        }
        byte[] encrypted = null;
        // Create an RijndaelManaged object
        // with the specified key and IV.
        using (RijndaelManaged rijAlg = new RijndaelManaged())
        {
            rijAlg.Mode = CipherMode.CFB;
            rijAlg.FeedbackSize = 8;
            rijAlg.BlockSize = 128;
            rijAlg.Padding = PaddingMode.None;

            rijAlg.Key = Key;
            rijAlg.IV = IV;

            // Create a decrytor to perform the stream transform.
            ICryptoTransform encryptor = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.IV);
            // Create the streams used for encryption.
            using (System.IO.MemoryStream msEncrypt = new System.IO.MemoryStream())
            {
                using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                {
                    using (System.IO.StreamWriter swEncrypt = new System.IO.StreamWriter(csEncrypt))
                    {

                        //Write all data to the stream.
                        swEncrypt.Write(plainText);
                    }
                    encrypted = msEncrypt.ToArray();
                }
            }
        }

        // Return the encrypted bytes from the memory stream.
        return encrypted;

    }

使用我最初使用的相同字符串、 key 和 IV 调用上述函数会产生以下密码:

249 (which is correct), 43, 74, 118, 241, 179, 235

我将 FeedbackSize 更改为 16，前两个字节是正确的，但它也给了我一个错误(要加密的数据的长度无效。)并将数组大小减少到 6 个字节。我一无所知。

这是 Rabbit 中使用 AESencryptStream 的一些示例代码的片段(他们选择将 IV 设置为与 key 相同的值)。看来我正确使用了这个功能，但如果我错了请告诉我:

const char key[16] = {
   '\x06', '\xa9', '\x21', '\x40', '\x36', '\xb8', '\xa1', '\x5b',
   '\x51', '\x2e', '\x03', '\xd5', '\x34', '\x12', '\x00', '\x06'
};
char bblock[8192];
AESstreamState ass;
memset(bblock, 'A', sizeof(bblock));
AESinitStream(&ass, key, key);
AESencryptStream(&ass, bblock, sizeof(bblock));
AESinitStream(&ass, key, key);
AESdecryptStream(&ass, bblock, sizeof(bblock));

Answer 1

在线看AES Encryption作为引用。

Hex values:
plaintext: 74657374616263 
key:       41413744443430333035394e36373038 
iv:        000102030405060708090A0B0C0D0E0F 

I'm not tested follows code, please test it on your pc.

DC(动态 C)

#use AES_CRYPT.LIB
#define AES_CFB_BLOCK_SIZE 16
#define PLAINTEXT_SIZE 7

//41413744443430333035394e36373038
const char key[AES_CFB_BLOCK_SIZE] = {
   '\x41', '\x41', '\x37', '\x44', '\x44', '\x34', '\x30', '\x33',
   '\x30', '\x35', '\x39', '\x4e', '\x36', '\x37', '\x30', '\x38'
};

//000102030405060708090A0B0C0D0E0F
const char iv[AES_CFB_BLOCK_SIZE] = {
   '\x00', '\x01', '\x02', '\x03', '\x04', '\x05', '\x06', '\x07',
   '\x08', '\x09', '\x0A', '\x0B', '\x0C', '\x0D', '\x0E', '\x0F'
};

//testabc = 74657374616263
const char plntxt[PLAINTEXT_SIZE] =
{
   't', 'e', 's', 't', 'a', 'b', 'c'
};

int main(void) {
   auto int i;
   auto char text[256];
   auto AESstreamState encrypt_state, decrypt_state;

   printf("Test case 1 - encrypt aes cfb\n");
   AESinitStream(&encrypt_state, key, iv);

   memcpy(text, plntxt, sizeof(plntxt));
   AESencryptStream(&encrypt_state, text, AES_CFB_BLOCK_SIZE);
   printf("Encrypted text:\n");
   for (i = 0; i < sizeof(plntxt); i++) {
      printf("%02x.", (int) text[i]);
      if (0 == ((i+1) % PLAINTEXT_SIZE)) printf("\n");
   }
   printf("\n");


   printf("Test case 2 - decrypt aes cfb \n");
   AESinitStream(&decrypt_state, key, iv);

   //memcpy(text, cyptxt, sizeof(cyptxt));
   AESdecryptStream(&decrypt_state, text, AES_CFB_BLOCK_SIZE);
   printf("Decrypted text:\n");
   for (i = 0; i < sizeof(cyptxt); i++) {
      printf("%02x.", (int) text[i]);
      if (0 == ((i+1) % PLAINTEXT_SIZE)) printf("\n");
   }
   printf("\n");

   return 0;
}

C#

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


namespace TestAES_CFB
{
    class Program
    {

        static byte[] AES_CFB_Encrypt(string plainText, byte[] Key, byte[] IV)
        {
            byte[] encrypted;
            using (Aes aes = Aes.Create())
            {
                aes.KeySize = 128; // 16 bytes
                aes.BlockSize = 128; // 16 bytes
                aes.Key = Key;
                aes.IV = IV;
                aes.Padding = PaddingMode.Zeros;
                aes.Mode = CipherMode.CFB;

                ICryptoTransform encryptor = aes.CreateEncryptor(aes.Key, aes.IV);
                using (MemoryStream msEncrypt = new MemoryStream())
                {
                    using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                    {
                        using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                        {
                            swEncrypt.Write(plainText);
                        }
                        encrypted = msEncrypt.ToArray();
                    }
                }
            }

            return encrypted;
        }

        static string AES_CFB_Decrypt(byte[] cipherText, byte[] Key, byte[] IV)
        {
            string plaintext = null;

            using (Aes aes = Aes.Create())
            {
                aes.KeySize = 128; // 16 bytes
                aes.BlockSize = 128; // 16 bytes
                aes.Key = Key;
                aes.IV = IV;
                aes.Padding = PaddingMode.Zeros;
                aes.Mode = CipherMode.CFB;


                ICryptoTransform decryptor = aes.CreateDecryptor(aes.Key, aes.IV);
                using (MemoryStream msDecrypt = new MemoryStream(cipherText))
                {
                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {
                        using (StreamReader srDecrypt = new StreamReader(csDecrypt))
                        {

                            plaintext = srDecrypt.ReadToEnd();
                        }
                    }
                }

            }
            return plaintext;
        }


        static void Main(string[] args)
        {
            const int AES_CFB_BLOCK_SIZE = 16;
            const int PLAINTEXT_SIZE = 7;

            //41413744443430333035394e36373038
            byte[] key = new byte[AES_CFB_BLOCK_SIZE] {0x41, 0x41, 0x37, 0x44, 0x44, 0x34, 0x30, 0x33, 0x30, 0x35, 0x39, 0x4e, 0x36, 0x37, 0x30, 0x38};

            //000102030405060708090A0B0C0D0E0F
            byte[] iv = new byte[AES_CFB_BLOCK_SIZE] { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,  0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F};

            //testabc = 74657374616263
            string plntxt = "testabc";

            using (Aes myAes = Aes.Create())
            {

                byte[] encrypted = AES_CFB_Encrypt(plntxt, key, iv);

                string decrypted  = AES_CFB_Decrypt(encrypted, key, iv);

                Console.WriteLine("Encrypted:  {0}", BitConverter.ToString(encrypted));
                Console.WriteLine("Decrypted: {0}", decrypted);
                Console.ReadLine();
            }

        }
    }
}