Sign a File to Create a .p7s (Detached Signature)

VBScript example to create a detached signature file (.p7s) for any type file. The signature can be verified by calling VerifyP7S and passing the original filename and the .p7s filename.

Download Chilkat Crypt ActiveX

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
Set outFile = fso.CreateTextFile("output.txt", True)

set crypt = CreateObject("Chilkat.Crypt2")

'  Any string argument automatically begins the 30-day trial.
success = crypt.UnlockComponent("30-day trial")
If (success <> 1) Then
    outFile.WriteLine(crypt.LastErrorText)
    WScript.Quit
End If

'  Use a digital certificate and private key from a PFX file (.pfx or .p12).
signingCertSubject = "Acme Inc"
pfxFilename = "/Users/chilkat/testData/pfx/acme.pfx"
pfxPassword = "test123"

set certStore = CreateObject("Chilkat.CertStore")
success = certStore.LoadPfxFile(pfxFilename,pfxPassword)
If (success <> 1) Then
    outFile.WriteLine(certStore.LastErrorText)
    WScript.Quit
End If

' cert is a Chilkat.Cert
Set cert = certStore.FindCertBySubjectCN(signingCertSubject)
If (cert Is Nothing ) Then
    outFile.WriteLine("Failed to find certificate by subject common name.")
    WScript.Quit
End If

'  Tell the crypt component to use this cert.
crypt.SetSigningCert cert

'  We can sign any type of file, creating a .p7s as output:
inFile = "/Users/chilkat/testData/pdf/sample.pdf"
sigFile = "/Users/chilkat/testData/p7s/sample.p7s"

success = crypt.CreateP7S(inFile,sigFile)
If (success = 0) Then
    outFile.WriteLine(crypt.LastErrorText)

    WScript.Quit
End If

success = crypt.VerifyP7S(inFile,sigFile)
If (success = 0) Then
    outFile.WriteLine(crypt.LastErrorText)

    WScript.Quit
End If

MsgBox "Success!"
outFile.Close