CS779/879

Assignment #3

Due Midnight, Wednesday   March 16, 2011

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PART I

Use lsof to trace back a user who is using “piping” to hide.

Show the details of your investigation in the context of the following example:

somethingelse % sock -s 10111

something % sock -s 10222 | sock somethingelse 10111

somethingmore % sock something 10222

PART II

Write the following programs:

NAME

soc - simultaneous open & close

med - Mediator for soc.

SYNOPSIS

soc <local_host> <local_port> <peer_host> <peer_port> <med_host> <med_port> <message>

med <port>

DESCRIPTION

The med program help the soc programs to start and terminates when both succeeds in establishing TCP connection and closing the established connection simultaneously.

Use the tcpdump to capture the SYN and FIN segments of the TCP connection.

You may test the Example implementation at:

http://www.cs.odu.edu/~cs779/spring11/assignments/a3/wahab/

something % med 10111

somethingmore % soc somethingmore 10222 somethingelse 10333 something 10111 Hussein

somethingelse % soc somethingelse 10333 somethingmore 10222 something 10111 “Abdel Wahab”