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Classic ASP

Duplicate openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

See more RSA Examples

Demonstrates how to duplicate the creation of an RSA signature produced by this OpenSSL command:
openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

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

set pkey = Server.CreateObject("Chilkat.PrivateKey")

' Load the private key from an RSA PEM file:
success = pkey.LoadPemFile("myKey.pem")

set rsa = Server.CreateObject("Chilkat.Rsa")

' Import the private key into the RSA component:
success = rsa.UsePrivateKey(pkey)
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( rsa.LastErrorText) & "</pre>"
    Response.End
End If

' OpenSSL uses BigEndian byte ordering:
rsa.LittleEndian = 0

' The resulting signature will be a Base64 string:
rsa.EncodingMode = "base64"

' For simplicity, we're not loading
' the data to be signed from a file.  We are instead simply
' using a literal string value.  
strData = "This is the text to be signed."

' Hash the input using MD5, and then sign the hash:
' Other valid hash algorithm choices are "md2" and "sha-1".
base64Sig = rsa.SignStringENC(strData,"md5")

Response.Write "<pre>" & Server.HTMLEncode( base64Sig) & "</pre>"

Response.Write "<pre>" & Server.HTMLEncode( "Success!") & "</pre>"

%>
</body>
</html>