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VB.NET

Duplicate openssl smime -decrypt -in some_file.dat.enc -binary -inform DER -inkey private.key -out some_file.dat

See more OpenSSL Examples

Demonstrates how to decrypt binary DER that was encrypted using the following openssl command:
openssl smime -encrypt -binary -aes-256-cbc -in some_file.dat -out some_file.dat.enc -outform DER cert.crt

Chilkat VB.NET Downloads

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.

' Duplicates the following openssl command:
' openssl smime -decrypt -in hello.txt.enc -binary -inform DER -inkey private.key -out hello.txt

Dim cert As New Chilkat.Cert
success = cert.LoadFromFile("qa_data/openssl/EE.cer")
If (success = False) Then
    Debug.WriteLine(cert.LastErrorText)
    Exit Sub
End If


Dim bd As New Chilkat.BinData
success = bd.LoadFile("qa_data/openssl/EE.key")
' Assuming success..

Dim privKey As New Chilkat.PrivateKey
success = privKey.LoadAnyFormat(bd,"")
If (success = False) Then
    Debug.WriteLine(privKey.LastErrorText)
    Exit Sub
End If


Dim crypt As New Chilkat.Crypt2
success = crypt.SetDecryptCert2(cert,privKey)
If (success = False) Then
    Debug.WriteLine(crypt.LastErrorText)
    Exit Sub
End If


crypt.CryptAlgorithm = "PKI"
success = crypt.CkDecryptFile("qa_data/openssl/hello.txt.enc","qa_output/hello.txt")
If (success = False) Then
    Debug.WriteLine(crypt.LastErrorText)
    Exit Sub
End If


Debug.WriteLine("Success.")