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C

HMAC Hex String

See more Encryption Examples

Demonstrates how to compute an HMAC using a hexidecimal key and data.

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C
#include <C_CkCrypt2.h>
#include <C_CkBinData.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkCrypt2 crypt;
    const char *keyHex;
    const char *dataHex;
    HCkBinData bd;
    const char *macHex;

    success = FALSE;

    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    crypt = CkCrypt2_Create();

    // Set the MAC algorithm to HMAC
    CkCrypt2_putMacAlgorithm(crypt,"hmac");

    // Our HMAC key will be the bytes represented in the following hex string.
    // In other words, the HMAC key is composed of the bytes 0x41, 0xC2, 0x1C, ...
    // (It is not composed of the us-ascii string '4', '1', 'C', ...)
    keyHex = "41C21CB9D7A02FC5D4FADB9E4755B9DE";
    success = CkCrypt2_SetMacKeyEncoded(crypt,keyHex,"hex");

    // Our desire is to HMAC the bytes represented in the following string:
    dataHex = "C22078065B01460001000000010062043BF5B18228C8E02D17BCFE4E00561FA6DEC216EA97195CEB579942E275C21932258E3CD391E507FF4E7FD4C787A8447DA111C54A9C1795E7FF4C0BAA2EDA";

    // We'll need to decode the hex to binary:
    bd = CkBinData_Create();
    CkBinData_AppendEncoded(bd,dataHex,"hex");

    // Do the HMAC-SHA256 hash and return as a hex string:
    CkCrypt2_putEncodingMode(crypt,"hex");
    CkCrypt2_putHashAlgorithm(crypt,"sha-256");
    macHex = CkCrypt2_macBdENC(crypt,bd);
    printf("%s\n",macHex);


    CkCrypt2_Dispose(crypt);
    CkBinData_Dispose(bd);

    }