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# File: $Id: pseudoipv6.py,v 1.2 2006/08/01 13:35:58 gnn Exp $
#
# Author: George V. Neville-Neil
#
# Description: A class that implements an IPv6 packet.
#
import pcs
import struct

class pseudoipv6(pcs.Packet):
    """A class that create an IPv6 pseudo header used
    for upper-layer checksums."""

    layout = pcs.Layout()

    def __init__(self, bytes = None):
        """IPv6 pseudo header from RFC 2460"""
        src = pcs.StringField("src", 16 * 8)
        dst = pcs.StringField("dst", 16 * 8)
        length = pcs.Field("length", 32)
        zero = pcs.Field("zero", 24)
        nh = pcs.Field("next_header", 8)
        pcs.Packet.__init__(self,
                            [src, dst, length, zero, nh], bytes);