pdb.py

The Packet Debugger, pdb is a program which allows people to work with packet streams as if they we

#!/usr/bin/env python
#
# Copyright (c) 2006, Neville-Neil Consulting
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# Redistributions of source code must retain the above copyright notice,
# this list of conditions and the following disclaimer.
#
# Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# Neither the name of Neville-Neil Consulting nor the names of its 
# contributors may be used to endorse or promote products derived from 
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# File: pdb.py
#
# Author: George V. Neville-Neil
#
# Description: This is the script which starts up the Packet Debugger.
# It is installed, along with all of its supporting modules, when the
# system is installed.

import sys
sys.path.insert(0, ".") # Look locally first.
from pktdbg import cli
from pktdbg import packetstream

class Options(object):

    list_length = 10 # How many lines to list before and after this one.
    layer = -1     # Pick a layer to display, None is all layers

    def __init__(self):
        pass

    def __repr__(self):
        return "list_length = %d\nlayer = %d\n" % (self.list_length, self.layer)

def main():
    """The Packet Debugger

    The packet debugger is a program that treats network packets, in
    the form of either live captured packets or packets read from a
    file stored using the standard pcap(3) library as statements which
    can be worked with in much the same way that a code debugger works
    with lines of code.

    """

    version = "Beta 0.1"

    # Standard argument parsing with the optparse module.
    # Currently there are no positional arguments with pdb.
    
    from optparse import OptionParser 
    parser = OptionParser() 

    parser.add_option("-f", "--file", dest="filename", 
                      help="pcap file to read") 
    parser.add_option("-i", "--interface", dest="interface",
                      help="Network interface to connect to.")

    (cmdln_options, args) = parser.parse_args() 
    
    options = Options()

    # Read in stream 0
    streams = []  # The list of streams we're working with.
    current = None  # The current stream number

    streams.append(packetstream.Stream(options, cmdln_options.filename, cmdln_options.interface))
    current = streams[0]
    
    # Jump into the cli

    pdbcli = cli.Command(current, options, streams)

    welcome = "Welcome to PDB version %s.\n" % version
    welcome += "For a list of commands type 'help <rtn>'\n"
    welcome += "For help on a command type 'help command <rtn>'"
    pdbcli.cmdloop(welcome)
    
# The canonical way to start a Python script.  Keep at the end.
if __name__ == "__main__":
    main()