Visual Basic 6.0

Create PKCS7 (CMS) EnvelopedData

Encrypt some data to a recipient by creating a PKCS7 (CMS) EnvelopedData structure. The data will be encrypted using a symmetric content-encryption algorithm (e.g., AES), and the randomly generated symmetric key will be encrypted using the recipient’s RSA public key extracted from their X.509 certificate. Visual Basic 6.0

Dim success As Long
success = 0

Dim crypt As New ChilkatCrypt2

' Specify the encryption to be used.
' "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped-data) message.
crypt.CryptAlgorithm = "pki"
crypt.Pkcs7CryptAlg = "aes"
crypt.KeyLength = 256
crypt.OaepHash = "sha256"
crypt.OaepPadding = 1

Dim cert As New ChilkatCert

' Use a certificate found in the Windows certificate store.
success = cert.LoadByCommonName("My Certificate")
If (success <> 1) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

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

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

' Get the result in multi-line BASE64 MIME format.
crypt.EncodingMode = "base64_mime"
crypt.Charset = "utf-8"

Dim result As String
result = crypt.EncryptStringENC(toBeEncrypted)
If (success <> 1) Then
    Debug.Print crypt.LastErrorText
    Exit Sub
End If

' -------------------------------------------------------------------------
' See the following example to decrypt what was created in this example
' Decrypt PKCS7 (CMS) EnvelopedData
' -------------------------------------------------------------------------

Debug.Print result

' Sample output:

' MIICSgYJKoZIhvcNAQcDoIICOzCCAjcCAQAxggHiMIIB3gIBADCBljCBgTELMAkGA1UEBhMCSVQx
' EDAOBgNVBAgMB0JlcmdhbW8xGTAXBgNVBAcMEFBvbnRlIFNhbiBQaWV0cm8xFzAVBgNVBAoMDkFj
' dGFsaXMgUy5wLkEuMSwwKgYDVQQDDCNBY3RhbGlzIENsaWVudCBBdXRoZW50aWNhdGlvbiBDQSBH
' MwIQPCWvkSv8oQ7xRmEHJ6TzEDA8BgkqhkiG9w0BAQcwL6APMA0GCWCGSAFlAwQCAQUAoRwwGgYJ
' KoZIhvcNAQEIMA0GCWCGSAFlAwQCAQUABIIBAKqHAPQNSsQoX7B2NH7QyEOWQRsSVs8oCHXmy8f4
' MVZD2er3bvYUCIomxpwbLEAl14qjUIMynahooYGgqip7+4FqL301G+BVjZVfEhHWj+VI1dAWnWuL
' VHlvc/pbQNBWqV8rKVJsNIsuAZkdj4WSwLVKxYkYX43B8fh/g71XN2DTJu7Z/824v48KBmgpQBOT
' 2q7IcDGxNPAFN2p6eavIVGn2LvhEbf/Fszyj+GR5tMcnQP1BOLJ3s3JzUBbvj8hcZrF1Vhl9HnTU
' YQx8G/KdW1mR+Wlhl3BWoK0LYKRTbnTx2BXOs0CY1SXOAdhKr01ZYjA+xW4nGzY0lfXS9QZjh9gw
' TAYJKoZIhvcNAQcBMB0GCWCGSAFlAwQBKgQQw0xTbfmnt0zjWHo5SaQIp4AgxTVY9E/Ncqy6t+RM
' 8y4c3Av62/wB8IpPUEmtM2OeuZo=