(Go) 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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    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    crypt := chilkat.NewCrypt2()

    crypt.SetCryptAlgorithm("pki")

    pem := chilkat.NewPem()
    success := pem.LoadPemFile("qa_data/pem/myPem.pem","password")
    if success != true {
        fmt.Println(pem.LastErrorText())
        crypt.DisposeCrypt2()
        pem.DisposePem()
        return
    }

    privkey := pem.GetPrivateKey(0)
    if pem.LastMethodSuccess() != true {
        fmt.Println(pem.LastErrorText())
        crypt.DisposeCrypt2()
        pem.DisposePem()
        return
    }

    cert := pem.GetCert(0)
    if pem.LastMethodSuccess() != true {
        privkey.DisposePrivateKey()
        fmt.Println(pem.LastErrorText())
        crypt.DisposeCrypt2()
        pem.DisposePem()
        return
    }

    success = crypt.SetDecryptCert2(cert,privkey)
    if success != true {
        privkey.DisposePrivateKey()
        cert.DisposeCert()
        fmt.Println(crypt.LastErrorText())
        crypt.DisposeCrypt2()
        pem.DisposePem()
        return
    }

    privkey.DisposePrivateKey()
    cert.DisposeCert()

    success = crypt.CkDecryptFile("qa_data/infile.enc","qa_output/outfile.dat")
    if success != true {
        fmt.Println(crypt.LastErrorText())
        crypt.DisposeCrypt2()
        pem.DisposePem()
        return
    }

    fmt.Println("Success.")

    crypt.DisposeCrypt2()
    pem.DisposePem()