QuickHash Library

C++ Interface

CHMAC::FinalHex

void FinalHex( char* pDest, bool bUpper = false );
 

Parameters

 pDest

    [out] Pointer to the text buffer that will receive the HMAC.

 bUpper

    [in] Uppercase flag. If bUpper is false, the received HMAC represents a lowercase string, otherwise it represents an uppercase string.

Remarks

Call this member function to retrieve the HMAC from the CHMAC object. The HMAC is retrieved as a null-terminated hexadecimal string in the text buffer pointed by pDest. The size of the text buffer pointed by pDest must be at least CHMAC<T>::HEXDIGESTSIZE characters. For example, the size of the text buffer pointed by pDest must be at least CHMAC<CMD5>::HEXDIGESTSIZE characters, if the HMAC is calculated using the MD5 hash algorithm.

After the FinalHex method is performed, the CHMAC object is initialized for new calculations, as it would be constructed again. To initialize the CHMAC object with another key, call the Init method.

Example

#include <fstream>
#include <QuickHash.h>

using namespace std;
using namespace QuickHash;

const unsigned int BUFF_SIZE = 1024;

int main()
{
    fstream file( "c:\\test.txt", ios::in | ios::binary );

    if( !file )
        return 1;

    unsigned char buff[ BUFF_SIZE ];
    char hmachex[ CHMAC<CPanama>::HEXDIGESTSIZE ]; //0 terminated

    char key[] = "My Password";

    //Instantiate a CHMAC object that uses PANAMA hash algorithm

    CHMAC<CPanama> hm( (const unsigned char*)key, strlen( key ) );

    //Calculate the HMAC incrementally block by block using Update

    while( !file.eof() )
    {
        file.read( ( char* )buff, BUFF_SIZE );
        hm.Update( buff, file.gcount() );
    }

    //Do final changes and get the HMAC in hex format

    hm.FinalHex( hmachex );

    //Use the HMAC
    //...

    file.close();

    return 0;
}

CHMAC Overview   |   Class Members   |   Useful Links   |   HashCalc

See Also    CHMAC::Final, CHMAC::Update, CHMAC::Init