如何将字节数组从C++返回到C#

Question

所以我一直在努力解决这个问题.我正在尝试将自己的AES 128库用于我的一个程序.该库测试并在C++中工作(适用于加密功能..我还没有实现其他功能)'加密'功能是这样的:

新代码

void Aes128Class::EncryptBlock(BYTE* outBlock, const BYTE* inBlock, const BYTE* cipherBlock)
{
    BYTE temp[16] = {0x00};
    Galois::XorBlock(temp, inBlock);
    Galois::XorBlock(temp, cipherBlock);

    BYTE expandedKey[176] = {0x00};
    memcpy(expandedKey, Key, 16);
    Galois::expand_key(expandedKey);

    Galois::XorBlock(temp, expandedKey);
    for(int i=16; i<160; i+=16)
    {
        Galois::DoRound(temp, &expandedKey[i]);
    }
    Galois::SubBytes(temp);
    Galois::ShiftRows(temp);
    Galois::XorBlock(temp, &expandedKey[160]);

    memcpy(outBlock, temp, 16);
}
void Aes128Class::EncryptData(BYTE* outBlock, size_t& outlen, const BYTE* inBlock, size_t length)
{
    float blockSize = (float)(length/16);
    blockSize = ceilf(blockSize);
    int newLength = (int)(blockSize*16);
    BYTE* temp = (BYTE*)malloc(newLength);
    BYTE* padd = (BYTE*)malloc(newLength);
    memset(temp, 0, newLength);
    memcpy(padd, inBlock, length);
    EncryptBlock(temp, padd, IV);
    for (int i=1; i<blockSize; i++)
    {
        EncryptBlock(&temp[i*16], &padd[i*16], &temp[(i-1)*16]);
    }
    outlen = newLength;
    memcpy(outBlock, temp, newLength);
}

这个想法是,如果plainText不是16字节的块增量,那么我强迫它.所以这就产生了一个可变大小的字节数组.它适用于我的C++测试,但当我调用它时,C#我会得到一些不同的错误...这需要一分钟来描述.

    [DllImport("CppAes128.dll", CallingConvention = CallingConvention.ThisCall,
        EntryPoint = "?EncryptData@Aes128Class@@QAEXPAEAAIPBEI@Z")]
    static extern void EncryptData(IntPtr pClass, ref IntPtr outblock, [Out]int OutLength, byte[] inBlock, int length);

当我调用它时,我得到了有效指针array和outlength.看起来现在的方式会导致访问冲突,但我可以得到结构工作,如果我改变[Out]int OutLength对ref IntPtr.有趣的是,如果我这样做ref int或ref uint它仍然"有效".所以,如果我这样做,我尝试阅读intptr,然后我得到访问冲突.我正在编译它作为一个x86 projectin .NET 4.0(因为我在某处看到3.5有一些错误的访问...)

这是我尝试过的C#.这有点乱,因为我已经玩了好几个小时(对不起):

    public byte[] EncryptData(byte[] plainText, int length)
    {
        byte[] enc = null;
        int len = 0;
        IntPtr pArray = IntPtr.Zero;
        EncryptData(theClass, ref pArray, len, plainText, length);

        Console.WriteLine(len);
        //enc = new byte[len];
        //Marshal.Copy(pArray, enc, 0, len);
        //Marshal.Release(pArray);
        //try
        //{
        //    int elementSize = Marshal.SizeOf(typeof(IntPtr));
        //    //IntPtr unmanagedArray = Marshal.AllocHGlobal(10 * elementSize);
        //    Console.WriteLine("Reading unmanaged memory:");
        //    // Print the 10 elements of the C-style unmanagedArray 
        //    for (int i = 0; i < 10; i++)
        //    {
        //        Console.WriteLine("{0:X2}:", Marshal.ReadByte(pArray, i));
        //    }

        //    Marshal.FreeHGlobal(pArray);

        //}
        //catch (Exception ex)
        //{
        //    Console.WriteLine("{0}\n{1}", ex.Source, ex.Message);
        //    Console.WriteLine("Win32({0})", Marshal.GetLastWin32Error());
        //}
        //Marshal.Release(pArray);
        return enc;
    }

这个工作的唯一时间是我刚制作一个静态大小的数组,并没有使用ref或marshal复制或任何东西..我认为我的签名是这样的

static extern void EncryptData(IntPtr pClass, byte[] outBlock, byte[] inBlock, int length);

这几乎是有效的,但问题是,当我做了一个foreach循环时,array它总是我放的大小...至少可以说令人沮丧.

那么我做错了什么？我怎么能让这个工作？我很沮丧.谢谢

哦,仅供参考,这是我不能再依赖的cryptlib了.我正在尝试重新编译一个不同的项目,它使用cryptlib静态库而不是共享,这会导致我的编译选项出现一些问题,而且回头的麻烦太大了.

已编辑以显示更多代码

这是我使用的测试.我找到了一个显示大量测试的网页,所以这就是我实现这一点.

void VerifyEncrypt16(const BYTE* expected, const BYTE* key, const BYTE* iv, const BYTE* plainText)
{
    BYTE actual[16] = {0x00};
    Aes128Class aes;
    aes.SetKey(key, 16);
    aes.SetIV(iv, 16);
    size_t len = 0;
    aes.EncryptData(actual, len, plainText, 16);
    _ASSERT(CompareTwoArrays(expected, actual));
}
void VerifyEncrypt16String(const char* expected, const char* key, const char* iv, const char* plainText)
{
    BYTE e[16];
    BYTE k[16];
    BYTE i[16];
    BYTE p[16];

    ByteUtil::StringToHex(expected, e);
    ByteUtil::StringToHex(key, k);
    ByteUtil::StringToHex(iv, i);
    ByteUtil::StringToHex(plainText, p);

    VerifyEncrypt16(e, k, i, p);
}
void CheckEncrypt16(void)
{
    _RPT0(_CRT_WARN, "Checking Encryption of a 16 byte number IV set to 0\n");
    //AESVS GFSbox test data for CBC
    VerifyEncrypt16String("0336763e966d92595a567cc9ce537f5e","00000000000000000000000000000000","00000000000000000000000000000000","f34481ec3cc627bacd5dc3fb08f273e6");
    VerifyEncrypt16String("a9a1631bf4996954ebc093957b234589","00000000000000000000000000000000","00000000000000000000000000000000","9798c4640bad75c7c3227db910174e72");
    VerifyEncrypt16String("ff4f8391a6a40ca5b25d23bedd44a597","00000000000000000000000000000000","00000000000000000000000000000000","96ab5c2ff612d9dfaae8c31f30c42168");
    VerifyEncrypt16String("dc43be40be0e53712f7e2bf5ca707209","00000000000000000000000000000000","00000000000000000000000000000000","6a118a874519e64e9963798a503f1d35");
    VerifyEncrypt16String("92beedab1895a94faa69b632e5cc47ce","00000000000000000000000000000000","00000000000000000000000000000000","cb9fceec81286ca3e989bd979b0cb284");
    VerifyEncrypt16String("459264f4798f6a78bacb89c15ed3d601","00000000000000000000000000000000","00000000000000000000000000000000","b26aeb1874e47ca8358ff22378f09144");
    VerifyEncrypt16String("08a4e2efec8a8e3312ca7460b9040bbf","00000000000000000000000000000000","00000000000000000000000000000000","58c8e00b2631686d54eab84b91f0aca1");

    //AESVS KeySbox test data for CBC
    VerifyEncrypt16String("6d251e6944b051e04eaa6fb4dbf78465","10a58869d74be5a374cf867cfb473859","00000000000000000000000000000000","00000000000000000000000000000000");
    //A TON OF MORE TESTS! etc etc etc        VerifyEncrypt16String("5c005e72c1418c44f569f2ea33ba54f3","00000000000000000000000000000000","00000000000000000000000000000000","fffffffffffffffffffffffffffffffe");
    VerifyEncrypt16String("3f5b8cc9ea855a0afa7347d23e8d664e","00000000000000000000000000000000","00000000000000000000000000000000","ffffffffffffffffffffffffffffffff");
}

Answer 1

如果您仍在寻找答案，此示例提供了一个起点。

基本上，从本机函数调用中分配内存块开始，然后调用回调到托管的地方（通过 ref ）传递数组及其从原始输入参数列表中保存的大小。

通过这种方式，您可以在托管代码中为托管代码分配内存块，并使用本机内容对其进行编辑。

http://msdn.microsoft.com/en-us/library/ektebyzx.aspx

最好找到一种替代方法，性能比较将是一个额外的好处:)