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Create CAdES p7m using AWS KMS to Sign in the Cloud

See more Signing in the Cloud Examples

Demonstrates how to create a CAdES p7m, using AWS KMS. The signing of the hash happens in the Cloud on AWS KMS. Everything else regarding the creation of CAdES happens locally within Chilkat.

Note: This example requires Chilkat v9.5.0.96 or greater.

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Dim success As Boolean = False

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

'  Load the certificate used for signing.  The certificate's private key is stored in AWS KMS
'  However, we still need the certificate locally (without private key).
Dim cert As ChilkatCert
cert.Initialize("cert")
success = cert.LoadFromFile("qa_data/certs/myCert.cer")
If success = False Then
    Log(cert.LastErrorText)
    Return
End If


'  Here's a screenshot showing the key ID of a private key in AWS KMS:
'  (image:https://example-code.com/images/aws_kms.jpg/endImage)

'  To sign using AWS KMS, 
'  add the following lines of code to specify your AWS authentication credentials,
'  and the ID of the KMS private key.
Dim jsonAwsKms As ChilkatJsonObject
jsonAwsKms.Initialize
'  Set the "service" equal to "aws_kms" to tell Chilkat to use AWS KMS for signing.
jsonAwsKms.UpdateString("service", "aws_kms")
jsonAwsKms.UpdateString("access_key", "ACCESS_KEY")
jsonAwsKms.UpdateString("secret_key", "SECRET_KEY")
'  Make sure to specify the correct region for your case.
jsonAwsKms.UpdateString("region", "us-west-2")
'  In the above screenshot, our key ID is "187012e8-008f-4fc7-b100-5efe6146dff2".  You will use your key ID.
jsonAwsKms.UpdateString("key_id", "187012e8-008f-4fc7-b100-5efe6146dff2")

success = cert.SetCloudSigner(jsonAwsKms)

Dim crypt As ChilkatCrypt2
crypt.Initialize("crypt")

success = crypt.SetSigningCert(cert)
If success = False Then
    Log(crypt.LastErrorText)
    Return
End If


'  The CadesEnabled property applies to all methods that create PKCS7 signatures. 
'  To create a CAdES-BES signature, set this property equal to true.
crypt.CadesEnabled = True

crypt.HashAlgorithm = "sha256"

Dim signedAttrs As ChilkatJsonObject
signedAttrs.Initialize
signedAttrs.UpdateInt("contentType", 1)
signedAttrs.UpdateInt("signingTime", 1)
signedAttrs.UpdateInt("messageDigest", 1)
signedAttrs.UpdateInt("signingCertificateV2", 1)
crypt.SigningAttributes = signedAttrs.Emit

'  You can sign any type of file..
Dim inputXmlPath As String = "qa_data/e-Invoice.xml"
Dim outputP7mPath As String = "qa_output/signed.p7m"

'  Create the CAdES-BES attached signature, which contains the original data.
'  Chilkat will build the .p7m locally, but will (internally) use ARSS
'  to do the RSA signing remotely.
success = crypt.CreateP7M(inputXmlPath, outputP7mPath)
If success = False Then
    Log(crypt.LastErrorText)
    Return
End If


Log("Success.")