(VB.NET UWP/WinRT) Encrypt using Cert to produce -----BEGIN PKCS7----- ... -----END PKCS7-----

Demonstrates how to encrypt using a certificate to produce output such as:

-----BEGIN PKCS7-----
MIIHPwYJKoZIhvcNAQcEoIIHMDCCBywC ...
...
...
-----END PKCS7-----

The certificate to be used is not your own, but the certificate of the intended recipient of the message.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads

Chilkat for the Universal Windows Platform (UWP)

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


Dim crypt As New Chilkat.Crypt2

'  Specify the encryption to be used.
'  "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped) message.
crypt.CryptAlgorithm = "pki"
crypt.Pkcs7CryptAlg = "aes"
crypt.KeyLength = 128
crypt.OaepHash = "sha256"
crypt.OaepPadding = True

'  A certificate is needed as the encryption key..
Dim cert As New Chilkat.Cert
Dim success As Boolean = cert.LoadFromFile("qa_data/certs/testCert.pem")
If (success <> True) Then
    Debug.WriteLine(cert.LastErrorText)
    Exit Sub
End If


'  Tell the crypt object to use the certificate.
crypt.SetEncryptCert(cert)

Dim toBeEncrypted As String = "This string is to be encrypted."

'  Get the result in multi-line BASE64 MIME format.
crypt.EncodingMode = "base64_mime"

Dim encryptedStr As String = crypt.EncryptStringENC(toBeEncrypted)
If (success <> True) Then
    Debug.WriteLine(crypt.LastErrorText)
    Exit Sub
End If


'  Make a "-----BEGIN PKCS7-----" ... "-----END PKCS7-----" sandwich...
Dim sb As New Chilkat.StringBuilder
sb.AppendLine("-----BEGIN PKCS7-----",True)
sb.Append(encryptedStr)
sb.AppendLine("-----END PKCS7-----",True)

Dim outStr As String = sb.GetAsString()

Debug.WriteLine(outStr)

'  Sample output:

'  -----BEGIN PKCS7-----
'  MIICYQYJKoZIhvcNAQcDoIICUjCCAk4CAQAxggH5MIIB9QIBADCBsTCBmzELMAkGA1UEBhMCR0Ix
'  GzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2FsZm9yZDEaMBgGA1UEChMR
'  Q09NT0RPIENBIExpbWl0ZWQxQTA/BgNVBAMTOENPTU9ETyBTSEEtMjU2IENsaWVudCBBdXRoZW50
'  aWNhdGlvbiBhbmQgU2VjdXJlIEVtYWlsIENBAhEAuBl4qE2MODB05C5h53M5UDA4BgkqhkiG9w0B
'  AQcwK6APMA0GCWCGSAFlAwQCAQUAoRgwFgYJKoZIhvcNAQEIMAkGBSsOAwIaBQAEggEAyZejlE37
'  awl0bCWVbOCqf9yLSN17mZRamG8FHDh3nNu11G0+oyJtsPDEnSKsQig0V67MZ+hcWV+uf4ytcjyx
'  H0gs5uex+LwkB+c3ZTOt18IYWFtRilg1HFy1ZN3t0D2QbxYy+i1TXOOwp3gAHL45vRCJ0FbKyQ36
'  pKl0XLe+lRvp2EiJCKVjxtX8VcZOKT4xkG7yOARaCQceth6pA58Dg0yzAz7w4nD2UgAlNzrXG69X
'  e+7e7yfBv47RRqFiQqDpCn+fM/PmFbUyqBppMwc64yP+fJek8VyJw2/UaXWWM4iSKSflk90tiHwf
'  loEU3It4arnSv94fZQo0v129aBqpWzBMBgkqhkiG9w0BBwEwHQYJYIZIAWUDBAECBBCohUgm5qX+
'  TE6PxtPCmWi8gCBgbNg39emAB+AqLozm+vSLjZOGfg3M52gccKUJ8tg8XQ==
'  -----END PKCS7-----