Go Requires Chilkat v11.7.0+

Replace the Authenticode Signature of an Already Signed File

See more Code Signing Examples

Demonstrates how to sign a file that already has an Authenticode signature, for example to sign it with a renewed code signing certificate. Starting in Chilkat v11.7.0, AddSignature removes the existing signature and replaces it with the new one. Before v11.7.0, signing an already signed EXE or DLL added a second signature entry instead. Go

    success := false

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

    //  Starting in Chilkat v11.7.0, AddSignature replaces the signature of a file that is already signed.
    //  (Before v11.7.0, signing an already signed EXE or DLL added a second signature entry
    //  instead of replacing the first.)
    //  
    //  This applies to every supported file type: EXE, DLL, MSI, PowerShell, and VBScript.

    path := "C:/someDir/MyApp.exe"

    codeSign := chilkat.NewCodeSign()
    sigInfo := chilkat.NewJsonObject()
    signerCert := chilkat.NewCert()

    //  Find out who signed the file.
    valid := codeSign.VerifySignature(path,sigInfo)
    if valid == true {
        codeSign.GetSignerCert(signerCert)
        fmt.Println("currently signed by: ", signerCert.SubjectCN())
        fmt.Println("certificate valid until: ", signerCert.ValidToStr())
    } else {
        fmt.Println("The file is not signed, or its signature is not valid.")
    }

    //  Load the certificate to sign with.  It must have access to its private key.
    cert := chilkat.NewCert()
    success = cert.LoadPfxFile("C:/someDir/myNewCodeSigningCert.pfx","pfx password")
    if success == false {
        fmt.Println(cert.LastErrorText())
        codeSign.DisposeCodeSign()
        sigInfo.DisposeJsonObject()
        signerCert.DisposeCert()
        cert.DisposeCert()
        return
    }

    //  Sign with SHA256, and ask a timestamp authority for a timestamp.  A timestamp lets the
    //  signature continue to validate after the code signing certificate has expired.
    //  
    //  {
    //    "hashAlg": "sha256",
    //    "timestampToken": {
    //      "enabled": true,
    //      "tsaUrl": "http://timestamp.digicert.com",
    //      "requestTsaCert": true,
    //      "hashAlg": "sha256"
    //    }
    //  }
    json := chilkat.NewJsonObject()
    json.UpdateString("hashAlg","sha256")
    json.UpdateBool("timestampToken.enabled",true)
    json.UpdateString("timestampToken.tsaUrl","http://timestamp.digicert.com")
    json.UpdateBool("timestampToken.requestTsaCert",true)
    json.UpdateString("timestampToken.hashAlg","sha256")

    //  Sign the file.  It is not necessary to call RemoveSignature first:
    //  the existing signature is removed and the new signature takes its place.
    success = codeSign.AddSignature(path,cert,json)
    if success == false {
        fmt.Println(codeSign.LastErrorText())
        codeSign.DisposeCodeSign()
        sigInfo.DisposeJsonObject()
        signerCert.DisposeCert()
        cert.DisposeCert()
        json.DisposeJsonObject()
        return
    }

    //  The file now has one signature, made with the new certificate.
    valid = codeSign.VerifySignature(path,sigInfo)
    if valid == false {
        fmt.Println(codeSign.LastErrorText())
        codeSign.DisposeCodeSign()
        sigInfo.DisposeJsonObject()
        signerCert.DisposeCert()
        cert.DisposeCert()
        json.DisposeJsonObject()
        return
    }

    success = codeSign.GetSignerCert(signerCert)
    if success == false {
        fmt.Println(codeSign.LastErrorText())
        codeSign.DisposeCodeSign()
        sigInfo.DisposeJsonObject()
        signerCert.DisposeCert()
        cert.DisposeCert()
        json.DisposeJsonObject()
        return
    }

    fmt.Println("now signed by: ", signerCert.SubjectCN())
    fmt.Println("certificate valid until: ", signerCert.ValidToStr())

    codeSign.DisposeCodeSign()
    sigInfo.DisposeJsonObject()
    signerCert.DisposeCert()
    cert.DisposeCert()
    json.DisposeJsonObject()