(Chilkat2-Python) 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).

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import sys
import chilkat2

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

crypt = chilkat2.Crypt2()

crypt.CryptAlgorithm = "pki"

pem = chilkat2.Pem()
success = pem.LoadPemFile("qa_data/pem/myPem.pem","password")
if (success != True):
    print(pem.LastErrorText)
    sys.exit()

# privkey is a CkPrivateKey
privkey = pem.GetPrivateKey(0)
if (pem.LastMethodSuccess != True):
    print(pem.LastErrorText)
    sys.exit()

# cert is a CkCert
cert = pem.GetCert(0)
if (pem.LastMethodSuccess != True):

    print(pem.LastErrorText)
    sys.exit()

success = crypt.SetDecryptCert2(cert,privkey)
if (success != True):

    print(crypt.LastErrorText)
    sys.exit()

success = crypt.CkDecryptFile("qa_data/infile.enc","qa_output/outfile.dat")
if (success != True):
    print(crypt.LastErrorText)
    sys.exit()

print("Success.")