(Xojo Plugin) Sign a File to Create a .p7m File (using a PFX)

Xojo Plugin example to sign a file creating a .p7m file as output. The .p7m contains the signed contents of the original file. It can be verified and restored by calling VerifyP7M.

Chilkat Xojo Plugin Download Xojo Plugin for Windows, Linux, Mac OS X, and ARM, ARM64

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

Dim crypt As New Chilkat.Crypt2

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

Dim certStore As New Chilkat.CertStore
Dim success As Boolean
success = certStore.LoadPfxFile(pfxFilename,pfxPassword)
If (success <> True) Then
    System.DebugLog(certStore.LastErrorText)
    Return
End If

Dim cert As Chilkat.Cert
cert = certStore.FindCertBySubjectCN(signingCertSubject)
If (certStore.LastMethodSuccess = False) Then
    System.DebugLog("Failed to find certificate by subject common name.")
    Return
End If

// Tell the crypt component to use this cert.
success = crypt.SetSigningCert(cert)

// We can sign any type of file, creating a .p7m as output:
Dim inFile As String
inFile = "/Users/chilkat/testData/pdf/sample.pdf"
Dim outputFile As String
outputFile = "/Users/chilkat/testData/p7m/sample.pdf.p7m"
success = crypt.CreateP7M(inFile,outputFile)
If (success = False) Then
    System.DebugLog(crypt.LastErrorText)

    Return
End If

// Verify and restore the original file:
success = crypt.SetVerifyCert(cert)

inFile = outputFile
outputFile = "/Users/chilkat/testData/pdf/restored.pdf"

success = crypt.VerifyP7M(inFile,outputFile)
If (success = False) Then
    System.DebugLog(crypt.LastErrorText)

    Return
End If

System.DebugLog("Success!")