Create S/MIME with Opaque Digital Signature

Download Chilkat MIME ActiveX

Visual Basic example to create a simple S/MIME message with an attached (opaque) digital signature.

Dim mime As New ChilkatMime

'  Any string argument automatically begins the 30-day trial.
Dim success As Long
success = mime.UnlockComponent("30-day trial")
If (success <> 1) Then
    MsgBox "MIME component unlock failed"
    Exit Sub
End If

'  Find our digital certificate from the Current User certificate store.
Dim ccs As New ChilkatCreateCS
Dim certStore As ChilkatCertStore
Set certStore = ccs.OpenCurrentUserStore()
Dim cert As ChilkatCert
Set cert = certStore.FindCertBySubjectCN("Chilkat Software, Inc.")

If (cert Is Nothing ) Then
    MsgBox cert.LastErrorText
    Exit Sub
End If

'  Our MIME object is currently empty.  Add some header fields
'  and a body:
mime.AddHeaderField "subject","this is a test"
mime.AddHeaderField "test123","this is a test 123"
mime.ContentType = "text/plain"
mime.Charset = "iso-8859-1"
mime.SetBodyFromPlainText "This is the body"

Text1.Text = Text1.Text & "Original MIME message:" & vbCrLf
Text1.Refresh
Text1.Text = Text1.Text & mime.GetMime() & vbCrLf
Text1.Refresh

'  The original MIME looks like this:
'  ----------------------------------
'  subject: this is a test
'  test123: this is a test 123
'  content-type: text/plain;
'  	 charset="iso-8859-1"
' 
'  This is the body
'  ----------------------------------

'  Convert the MIME to a signed message.  The original MIME
'  is embedded in
success = mime.ConvertToSigned(cert)
If (success <> 1) Then
    MsgBox mime.LastErrorText
    Exit Sub
End If

Text1.Text = Text1.Text & "----------------------------------" & vbCrLf
Text1.Refresh
Text1.Text = Text1.Text & "Signed Message:" & vbCrLf
Text1.Refresh
Text1.Text = Text1.Text & mime.GetMime() & vbCrLf
Text1.Refresh

MsgBox "Success!"

'  The resulting S/MIME looks like this:
'  --------------------------------
'  subject: this is a test
'  test123: this is a test 123
'  content-disposition: attachment;
'  	 filename="smime.p7m"
'  content-transfer-encoding: base64
'  content-type: application/x-pkcs7-mime;
'  	name="smime.p7m";smime-type=signed-data
' 
'  MIIGgAYJKoZIhvcNAQcCoIIGcTCCBm0CAQExCzAJBgUrDgMCGgUAMIGKBgkqhkiG9w0BBwGg
'  fQR7c3ViamVjdDogdGhpcyBpcyBhIHRlc3QNCnRlc3QxMjM6IHRoaXMgaXMgYSB0ZXN0IDEy
'  Mw0KY29udGVudC10eXBlOiB0ZXh0L3BsYWluOw0KCSBjaGFyc2V0PSJpc28tODg1OS0xIg0K
'  DQpUaGlzIGlzIHRoZSBib2R5oIID2TCCA9UwggM+oAMCAQICEHii5NwCYuzOsaLXvSTV15Iw
'  DQYJKoZIhvcNAQEFBQAwVTELMAkGA1UEBhMCWkExJTAjBgNVBAoTHFRoYXd0ZSBDb25zdWx0
'  aW5nIChQdHkpIEx0ZC4xHzAdBgNVBAMTFlRoYXd0ZSBDb2RlIFNpZ25pbmcgQ0EwHhcNMDcw
'  MTE1MDAwMDAwWhcNMDgwMTE1MjM1OTU5WjCBnTELMAkGA1UEBhMCVVMxETAPBgNVBAgTCEls
'  bGlub2lzMRAwDgYDVQQHEwdXaGVhdG9uMR8wHQYDVQQKExZDaGlsa2F0IFNvZnR3YXJlLCBJ
'  bmMuMScwJQYDVQQLEx5TZWN1cmUgQXBwbGljYXRpb24gRGV2ZWxvcG1lbnQxHzAdBgNVBAMT
'  FkNoaWxrYXQgU29mdHdhcmUsIEluYy4wggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIB
'  AQDBHa3pv8qfhXM0I6WPVgaQfENg9Wd9k0h47uGa62t4rqSv3jGb1GVCf6+Q3W5EyG9Js512
'  z4Hbmj4DIB64GYuy7Gg1EIL0BRtrfuljx4vTgBpMQCbfnS1+ccZPjiOhJ0U+hbkP3VMNqt7q
'  rlRppxx0S1dTj8saqH6ccH0h1+3RL+sik/Y8r1MDBDlXx2Uy4FBAD4FQKDkxj2ipmC2eRfs7
'  o4lKTwxPSVSFWDsQCB72JTHsS7ihYrzx+Q6jzWmoeiBOkZ/LieJtaDvZeQ+TXfmV4zD8mZ7f
'  urs5H/Obodx4WXLI7RYvV9jHT0+lhuPWVg29WjyffyiFPxP/uHc3gZSVAgMBAAGjgdgwgdUw
'  DAYDVR0TAQH/BAIwADA+BgNVHR8ENzA1MDOgMaAvhi1odHRwOi8vY3JsLnRoYXd0ZS5jb20v
'  VGhhd3RlQ29kZVNpZ25pbmdDQS5jcmwwHwYDVR0lBBgwFgYIKwYBBQUHAwMGCisGAQQBgjcC
'  ARYwHQYDVR0EBBYwFDAOMAwGCisGAQQBgjcCARYDAgeAMDIGCCsGAQUFBwEBBCYwJDAiBggr
'  BgEFBQcwAYYWaHR0cDovL29jc3AudGhhd3RlLmNvbTARBglghkgBhvhCAQEEBAMCBBAwDQYJ
'  KoZIhvcNAQEFBQADgYEABQxzFRt6jkdMMoxrEwUXLeID2L+R7hUsXD3vIQbetotMdlSVHBXH
'  AsYuZbzV1j/ricQMSAqLch+6iF8DRrc3ct3vPAvV/+F0balCKAty8zKY/2OPoMRDE6zTeIAM
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'  BgNVBAYTAlpBMSUwIwYDVQQKExxUaGF3dGUgQ29uc3VsdGluZyAoUHR5KSBMdGQuMR8wHQYD
'  VQQDExZUaGF3dGUgQ29kZSBTaWduaW5nIENBAhB4ouTcAmLszrGi170k1deSMAkGBSsOAwIa
'  BQCgXTAYBgkqhkiG9w0BCQMxCwYJKoZIhvcNAQcBMBwGCSqGSIb3DQEJBTEPFw0wNzA0MDQx
'  OTU1NDVaMCMGCSqGSIb3DQEJBDEWBBSXCN4QT4iPlNbNV3X7AzYezFL9oDANBgkqhkiG9w0B
'  AQEFAASCAQBqnhXsUVYMz2y92Qg0ciB1wVxP6DC8cgTPPIWfSFAcIR6Irk4BqzS5LarDZlfB
'  k85poqggff/m5kuyJfUNehTC0VnhAasCX0VjU+Bsr1k0c7gejges1EiuNJJo7q4Usp3+c5k9
'  ZSEIM95hp2rDKyzZdyvSAbFGI029RII0SNyU6g6rX3/FZhJqc+DbhLHax3RMERFqLvdmmREz
'  zIcRbt5y3VR3+bjD0tnvP5ynlg3rT4ubKWS/OormEPc20FwTHb8nCep3ZyGrUKusD7AWV3qv
'  0+IKpAWNsZ7CgDjcR+j9oz7Q8Y/17FgHflEypf3xR5TWBY/tCwx02GT7a9vpXbHT
' 
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