(Classic ASP) HMAC Hex String

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

Chilkat ActiveX Downloads

ActiveX for 32-bit and 64-bit Windows

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<%
' This example assumes the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.Crypt2")
set crypt = Server.CreateObject("Chilkat.Crypt2")

' Set the MAC algorithm to HMAC
crypt.MacAlgorithm = "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 = crypt.SetMacKeyEncoded(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:
' For versions of Chilkat < 10.0.0, use CreateObject("Chilkat_9_5_0.BinData")
set bd = Server.CreateObject("Chilkat.BinData")
success = bd.AppendEncoded(dataHex,"hex")

' Do the HMAC-SHA256 hash and return as a hex string:
crypt.EncodingMode = "hex"
crypt.HashAlgorithm = "sha-256"
macHex = crypt.MacBdENC(bd)
Response.Write "<pre>" & Server.HTMLEncode( macHex) & "</pre>"

%>
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