Classic ASP

RSA Hash Binary Data and Sign (and Verify)

Demonstrates how to sign the hash of binary data. Also demonstrates how to verify the RSA signature.

Chilkat Classic ASP Downloads

Classic ASP

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<%
success = 0

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

' Load an RSA private key for signing.
set privKey = Server.CreateObject("Chilkat.PrivateKey")
success = privKey.LoadEncryptedPemFile("qa_data/pem/rsa_passwd.pem","passwd")
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( privKey.LastErrorText) & "</pre>"
    Response.End
End If

set rsa = Server.CreateObject("Chilkat.Rsa")
success = rsa.UsePrivateKey(privKey)

' We have some binary data (in hex) to sign
originalData = "0102030405060708090A"
set bdData = Server.CreateObject("Chilkat.BinData")
success = bdData.AppendEncoded(originalData,"hex")

' Hash (SHA-256) and sign the hash:
set bdSignature = Server.CreateObject("Chilkat.BinData")
success = rsa.SignBd(bdData,"sha256",bdSignature)
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( rsa.LastErrorText) & "</pre>"
    Response.End
End If

' Show the RSA signature in base64
Response.Write "<pre>" & Server.HTMLEncode( bdSignature.GetEncoded("base64")) & "</pre>"

' ------------------------------------------
' Get the public key from the private key
set pubKey = Server.CreateObject("Chilkat.PublicKey")
success = privKey.ToPublicKey(pubKey)

' Verify the signature..
set rsa2 = Server.CreateObject("Chilkat.Rsa")
success = rsa2.UsePublicKey(pubKey)

bVerified = rsa2.VerifyBd(bdData,"sha256",bdSignature)
Response.Write "<pre>" & Server.HTMLEncode( "signature verified: " & bVerified) & "</pre>"

%>
</body>
</html>