VBScript

Duplicate openssl dgst -sha256 -verify pubKey.pem -signature signature.sig in.dat

See more OpenSSL Examples

Demonstrates how to duplicate this OpenSSL command:

openssl dgst -sha256 -verify pubKey.pem -signature signature.sig in.dat

The in.dat file contains the original data that was signed, and can contain text or binary data of any type. The above OpenSSL command does the following:

1. Creates a SHA256 digest of the contents of the input file.
2. Verifies the SHA256 digest using the public key.

VBScript

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

success = 0

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

set pubKey = CreateObject("Chilkat.PublicKey")

' Load the public key from an PEM file:
success = pubKey.LoadFromFile("pubKey.pem")
If (success = 0) Then
    outFile.WriteLine(pubKey.LastErrorText)
    WScript.Quit
End If

' Load the data of the original file that was signed.
set bdFileData = CreateObject("Chilkat.BinData")
success = bdFileData.LoadFile("in.dat")

' Load the signature.
set bdSig = CreateObject("Chilkat.BinData")
success = bdSig.LoadFile("signature.sig")

set rsa = CreateObject("Chilkat.Rsa")

' Import the public key into the RSA component:
success = rsa.UsePublicKey(pubKey)
If (success = 0) Then
    outFile.WriteLine(rsa.LastErrorText)
    WScript.Quit
End If

' OpenSSL uses big-endian.
rsa.LittleEndian = 0

success = rsa.VerifyBd(bdFileData,"sha256",bdSig)
If (success <> 1) Then
    outFile.WriteLine(rsa.LastErrorText)
    outFile.WriteLine("The signature was invalid.")
    WScript.Quit
End If

outFile.WriteLine("The signature was verified.")

outFile.Close