Index

1. Some Questions from 2003

• Given that /etc/passwd contains:

• majordom:*:30:31:Majordomo:/usr/lib/majordomo:/bin/sh
  postgres:*:31:32:postgres:/var/lib/postgres:/bin/sh
  www-data:*:33:33:www-data:/var/www:/bin/sh
  backup:*:34:34:backup:/var/backups:/bin/sh
  msql:*:36:36:Mini SQL Database Manager:/var/lib/msql:/bin/sh
  operator:*:37:37:Operator:/var:/bin/sh
  list:*:38:38:SmartList:/var/list:/bin/sh
  irc:*:39:39:ircd:/var:/bin/sh
  gnats:*:41:41:Gnats Bug-Reporting System:/var:/bin/sh

• What does the following python program display when run? Give a line by line commentary for this program.

• #!/usr/bin/python
  
  import sys, string
  
  
  for line in open(’/etc/passwd’).readlines():
      words = string.split(line, ’:’)
      if len(words) >= 5:
          print words[0], words[2:4], words[-1]

• 
  12 marks
• Using an example show clearly and explain how a GNU/Linux client and server are configured such that the client can import a filesystem from the server using NFS.
  11 marks
• For the three scripting languages: expect, python and bash give a practical example of how each language might be used to automate a task. Choose a different example for each language and say why the language is suitable for such a task.
  9 marks
  

2. Homework

• Comment on some of the security issues surrounding maintaining an ftp server on GNU/Linux.

  8 marks

• Describe two methods of restricting ftp access on a GNU/Linux ftp server and discuss their merits.
  12 marks
  

3. Practice exam question from 2005

• #!/usr/bin/expect
  
  
  log_user 0
  set localdir foo
  spawn ssh -l root linuxserver
  expect "Password: "
  send "wxyz1234\r"
  expect "\\$"
  send "cd $localdir"
  expect "\\$"
  send "[lindex $argv 0]\r"
  interact

• (a) Provide a line by line commentary of how the above script operates. Ignore the first line.
  8 marks
• (b) Give an example of how the above script might be invoked at the command line. Also mention the advantage and disadvantage of using this script. Comment on security implications of using this script as a system administrator.
  12 marks
  

4. Revision guidelines

• revise all topics
• but special attention should be given to the following: ftp server, expect, cracking, encryption etc, python, ntfs

Index

This document was produced using groff-1.19.