compute_response.py 文件源码

def _get_channel_bindings_value(server_certificate_hash):
        """
        https://msdn.microsoft.com/en-us/library/windows/desktop/dd919963%28v=vs.85%29.aspx?f=255&MSPPError=-2147217396
        https://blogs.msdn.microsoft.com/openspecification/2013/03/26/ntlm-and-channel-binding-hash-aka-extended-protection-for-authentication/

        Get's the MD5 hash of the gss_channel_bindings_struct to add to the AV_PAIR MSV_AV_CHANNEL_BINDINGS.
        This method takes in the SHA256 hash (Hash of the DER encoded certificate of the server we are connecting to)
        and add's it to the gss_channel_bindings_struct. It then gets the MD5 hash and converts this to a
        byte array in preparation of adding it to the AV_PAIR structure.

        :param server_certificate_hash: The SHA256 hash of the server certificate (DER encoded) NTLM is authenticated to
        :return channel_bindings: An MD5 hash of the gss_channel_bindings_struct to add to the AV_PAIR MsvChannelBindings
        """
        # Channel Binding Tokens support, used for NTLMv2
        # Decode the SHA256 certificate hash
        certificate_digest = base64.b16decode(server_certificate_hash)

        # Initialise the GssChannelBindingsStruct and add the certificate_digest to the application_data field
        gss_channel_bindings = GssChannelBindingsStruct()
        gss_channel_bindings[gss_channel_bindings.APPLICATION_DATA] = 'tls-server-end-point:'.encode() + certificate_digest

        # Get the gss_channel_bindings_struct and create an MD5 hash
        channel_bindings_struct_data = gss_channel_bindings.get_data()
        channel_bindings_hash = hashlib.md5(channel_bindings_struct_data).hexdigest()

        try:
            cbt_value = bytearray.fromhex(channel_bindings_hash)
        except TypeError:
            # Work-around for Python 2.6 bug
            cbt_value = bytearray.fromhex(unicode(channel_bindings_hash))

        channel_bindings = bytes(cbt_value)
        return channel_bindings