HMAC SHA-1 Matching FIPS Examples

Provides an example of computing an HMAC-SHA1 digest to duplicate the FIPS examples at http://csrc.nist.gov/publications/fips/fips198/fips-198a.pdf

Download Chilkat Crypt ActiveX

Dim crypt As New ChilkatCrypt2

Dim success As Long
success = crypt.UnlockComponent("Anything for 30-day trial.")
If (success <> 1) Then
    MsgBox crypt.LastErrorText
    Exit Sub
End If

Dim strToSign As String
strToSign = "Sample #1"

'  64-byte key
Dim key As String
key = "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f"

'  The expected result:
'  (from Appendix A.1 at http://csrc.nist.gov/publications/fips/fips198/fips-198a.pdf )
Dim expectedResult As String
expectedResult = "4f4ca3d5d68ba7cc0a1208c9c61e9c5da0403c0a"

'  Here is the code to duplicate the results:
crypt.HashAlgorithm = "sha-1"
crypt.EncodingMode = "hex"

crypt.SetHmacKeyEncoded key,"hex"

Dim mac As String
mac = crypt.HmacStringENC(strToSign)

Text1.Text = Text1.Text & "Computed: " & mac & vbCrLf
Text1.Text = Text1.Text & "Expected: " & expectedResult & vbCrLf