layer3.py 文件源码

def validate(self):
        """
        Validate that the contents of this object conform to protocol specs.
        """
        # Check if the traffic class fits in 8 bits
        if not isinstance(self.traffic_class, int) or not (0 <= self.traffic_class < 2 ** 8):
            raise ValueError("Traffic class must be an unsigned 8 bit integer")

        # Check if the flow label fits in 20 bits
        if not isinstance(self.flow_label, int) or not (0 <= self.flow_label < 2 ** 20):
            raise ValueError("Flow label must be an unsigned 20 bit integer")

        # Check if the next header fits in 8 bits
        if not isinstance(self.next_header, int) or not (0 <= self.next_header < 2 ** 8):
            raise ValueError("Next header type must be an unsigned 8 bit integer")

        # Check if the hop limit fits in 8 bits
        if not isinstance(self.hop_limit, int) or not (0 <= self.hop_limit < 2 ** 8):
            raise ValueError("Hop limit must be an unsigned 8 bit integer")

        # Check if the source and destination are IPv6 addresses
        if not isinstance(self.source, IPv6Address):
            raise ValueError("Source must be an IPv6 address")

        if self.source.is_multicast:
            raise ValueError("Source must be a non-multicast IPv6 address")

        if not isinstance(self.destination, IPv6Address):
            raise ValueError("Destination must be an IPv6 address")

        # Check if the payload is a protocol element
        if not isinstance(self.payload, ProtocolElement):
            raise ValueError("Payload must be a protocol element")

        # Check if all options are allowed
        self.validate_contains([self.payload])
        self.payload.validate()