VB.NET Requires Chilkat v11.5.0+

Sign PDF using ARSS (Aruba Remote Signing Service)

See more Signing in the Cloud Examples

Demonstrates how to digitally sign a PDF using the Aruba Remote Signing Service (ARSS). The example loads a local PDF and certificate, configures the ARSS cloud signer credentials, specifies the OTP authentication type with typeOtpAuth, and creates an LTV-enabled signed PDF where the private key remains protected on the Aruba signing server.

VB.NET

Dim success As Boolean = False

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

Dim pdf As New Chilkat.Pdf

'  Load the PDF that will be digitally signed.
success = pdf.LoadFile("qa_data/pdf/hello.pdf")
If (success = False) Then
    Debug.WriteLine(pdf.LastErrorText)
    Exit Sub
End If


'  Signing options are specified in a JSON object.
Dim json As New Chilkat.JsonObject

'  Enable LTV (Long-Term Validation).
'  When ltvOcsp is true, OCSP validation information is embedded in the PDF
'  so that signature validation can continue to succeed in the future,
'  even if the original OCSP responder is no longer available.
json.UpdateBool("ltvOcsp",True)

'  Specify the visual appearance of the signature on the PDF page.
json.UpdateInt("page",1)
json.UpdateString("appearance.y","top")
json.UpdateString("appearance.x","left")
json.UpdateString("appearance.fontScale","10.0")

'  Text lines displayed in the visible signature appearance.
'  Special values such as "cert_cn" and "current_dt" are replaced
'  with the certificate common name and current date/time.
json.UpdateString("appearance.text[0]","Digitally signed by: cert_cn")
json.UpdateString("appearance.text[1]","current_dt")
json.UpdateString("appearance.text[2]","This is an LTV-enabled signature.")

'  Load the signing certificate.
'  
'  The private key is NOT stored locally.  Instead, the private key is
'  stored and protected on the Aruba Remote Signing Service (ARSS).
'  
'  Even though the signing operation will occur remotely, Chilkat still
'  needs the corresponding public certificate locally so that it can
'  construct the CMS/PAdES signature and embed the certificate chain
'  in the signed PDF.
Dim cert As New Chilkat.Cert
success = cert.LoadFromFile("qa_data/certs/myCert.cer")
If (success = False) Then
    Debug.WriteLine(cert.LastErrorText)
    Exit Sub
End If


'  Configure Aruba Remote Signing Service (ARSS) credentials.
'  
'  When SetCloudSigner is called, Chilkat is instructed to perform
'  cryptographic signing operations through the ARSS web service.
'  The PDF is assembled locally, but the actual RSA signature operation
'  is performed remotely using the private key held by Aruba.
Dim jsonArss As New Chilkat.JsonObject

'  Required.  Indicates that the cloud signing provider is ARSS.
jsonArss.UpdateString("service","ARSS")

'  The ARSS certificate identifier (for example, "AS0").
'  This identifies which remote certificate/private key pair should be used.
'  The remote certificate should correspond to the certificate loaded above.
jsonArss.UpdateString("certID","YOUR_ARSS_CERT_ID")

'  OTP password associated with the Aruba remote-signing account.
'  Depending on the ARSS configuration, an OTP may be required to
'  authorize each signing operation.
jsonArss.UpdateString("otpPwd","YOUR_OTP_PWD")

'  Specifies the OTP authentication environment.
'  
'  Common values are:
'    "demoprod" - Demo/Test environment
'    "prod"     - Production environment
'  
'  This value is sent to the ARSS service and determines how the OTP
'  authentication is validated.  The correct value depends on the type
'  of Aruba account and environment that has been provisioned.
'  
'  If signing fails with an authentication-related error, verify that
'  the typeOtpAuth value matches the environment associated with the
'  ARSS account credentials being used.
jsonArss.UpdateString("typeOtpAuth","demoprod")

'  ARSS account username.
jsonArss.UpdateString("user","YOUR_ARSS_USERNAME")

'  ARSS account password.
jsonArss.UpdateString("userPWD","YOUR_ARSS_PASSWORD")

'  Beginning with Chilkat v11.5.0, the ARSS endpoint can be explicitly
'  specified.  This allows the application to target a particular
'  Aruba signing service endpoint when required.
jsonArss.UpdateString("endpoint","https://app1.firma-remota.it/ArubaSignerService/webresources/signerservice")

success = cert.SetCloudSigner(jsonArss)
If (success = False) Then
    Debug.WriteLine(cert.LastErrorText)
    Exit Sub
End If


'  Associate the certificate with the PDF object.
'  All subsequent signing operations will use this certificate.
success = pdf.SetSigningCert(cert)
If (success = False) Then
    Debug.WriteLine(pdf.LastErrorText)
    Exit Sub
End If


'  Create the signed PDF.
'  
'  Chilkat performs all PDF processing locally.  When the time comes
'  to generate the cryptographic signature value, Chilkat sends the
'  hash to ARSS, which signs it using the remote private key and returns
'  the signature.  The private key never leaves the Aruba service.
success = pdf.SignPdf(json,"qa_output/hello_ltv_signed.pdf")
If (success = False) Then
    Debug.WriteLine(pdf.LastErrorText)
    Exit Sub
End If


Debug.WriteLine("The PDF has been successfully cryptographically signed with long-term validation.")