HMACSHA1 off by 2 bytes

Question

I am using this class in MSVC++ 2010 Express: http://www.codeproject.com/KB/recipes/HMACSHA1class.aspx. I am running Vista 32bit. Pretty much to get it working I just changed...

SHA1.cpp:

fIn = fopen(szFileName, "rb");

to

fIn = fopen_s(szFileName, "rb");

because without this change it would say: "error C3861: 'fopen': identifier not found".

the code I used in int main is:

BYTE Key[20] ;
BYTE digest[20] ; 
unsigned char test[] = "Hi There" ;
memset(Key, 0x0b, 20) ;
CHMAC_SHA1 HMAC_SHA1 ;
HMAC_SHA1.HMAC_SHA1(test, strlen((const char *)test), Key, sizeof(Key), digest) ;

for(int i=0;i<sizeof(digest);i++)
    std::cout << hex << (int)digest[i];

int a;
std::cin >> a;

// Check with digest equal to 0xb617318655057264e28bc0b6fb378c8ef146be00
// or not

The problem is my digest is equal to: 0xb61731865557264e28bc0b6fb378c8ef146be0 and it suppose to be equal to 0xb617318655057264e28bc0b6fb378c8ef146be00. Any help on what is wrong with this code and how to get it working would help a lot...

Or maybe someone can point me into the right direction for a better HMACSHA1 class. CryptoAPI for win32 is to complex and silly.

Answer 1

I guess it's because some byte-values in digest are < 10 which means only one character is written.

Maybe this solves your problem:

for(int i=0;i<sizeof(digest);i++)
    std::cout << setfill('0') << setw(2) << hex << (int)digest[i];