(PureBasic) Duplicate OpensSSL Command that Decrypts Binary DER

This example duplicates the following:

openssl smime -decrypt -in INPUT_FILE -inform der -binary -out OUTPUT_FILE -recip PEM_CERT_AND_KEY -passin pass:PRIVKEY_PASSWORD

Note: Although "smime" is the OpenSSL command, we're not really dealing with S/MIME. The arguments "-inform der -binary" indicate that the input is simply the binary DER (i.e. the PKCS7 binary encrypted object). The output can be any type of file (whatever was encrypted).

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkCert.pb"
IncludeFile "CkCrypt2.pb"
IncludeFile "CkPrivateKey.pb"
IncludeFile "CkPem.pb"

Procedure ChilkatExample()

    success.i = 0

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

    crypt.i = CkCrypt2::ckCreate()
    If crypt.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkCrypt2::setCkCryptAlgorithm(crypt, "pki")

    pem.i = CkPem::ckCreate()
    If pem.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkPem::ckLoadPemFile(pem,"qa_data/pem/myPem.pem","password")
    If success = 0
        Debug CkPem::ckLastErrorText(pem)
        CkCrypt2::ckDispose(crypt)
        CkPem::ckDispose(pem)
        ProcedureReturn
    EndIf

    privkey.i = CkPrivateKey::ckCreate()
    If privkey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkPem::ckPrivateKeyAt(pem,0,privkey)
    If success = 0
        Debug CkPem::ckLastErrorText(pem)
        CkCrypt2::ckDispose(crypt)
        CkPem::ckDispose(pem)
        CkPrivateKey::ckDispose(privkey)
        ProcedureReturn
    EndIf

    cert.i = CkCert::ckCreate()
    If cert.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkPem::ckCertAt(pem,0,cert)
    If success = 0
        Debug CkPem::ckLastErrorText(pem)
        CkCrypt2::ckDispose(crypt)
        CkPem::ckDispose(pem)
        CkPrivateKey::ckDispose(privkey)
        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    success = CkCrypt2::ckSetDecryptCert2(crypt,cert,privkey)
    If success = 0
        Debug CkCrypt2::ckLastErrorText(crypt)
        CkCrypt2::ckDispose(crypt)
        CkPem::ckDispose(pem)
        CkPrivateKey::ckDispose(privkey)
        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    success = CkCrypt2::ckCkDecryptFile(crypt,"qa_data/infile.enc","qa_output/outfile.dat")
    If success = 0
        Debug CkCrypt2::ckLastErrorText(crypt)
        CkCrypt2::ckDispose(crypt)
        CkPem::ckDispose(pem)
        CkPrivateKey::ckDispose(privkey)
        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    Debug "Success."


    CkCrypt2::ckDispose(crypt)
    CkPem::ckDispose(pem)
    CkPrivateKey::ckDispose(privkey)
    CkCert::ckDispose(cert)


    ProcedureReturn
EndProcedure