View source for Linux Januar 2012/Add users

__NOTOC__
=Purpose=
When adding students on a Linux/UNIX box its desirable to let the students choice their own login names.
==How to add student logins==
Make a username and password public to the students. When the students login they are prompted for desired loginname/password
= Adding the create-students account=
Add user '''ny''' with password '''ny''' or whatever username/password you prefer to make public to the students. remember to change all references in the following to the username you choice.
==File: /home/ny/.profile==
Add the following line to the start of '''/home/ny/.profile'''
<source lang=cli>
trap '' 1 2 3 15
</source>

Add the following two lines to the end of '''/home/ny/.profile'''
<source lang=bash>
/home/ny/bin/nybruger
exit
</source>
==File: /etc/sudoers==
Add the following line to '''/etc/sudoers''' using visudo.
<source lang=bash>
ny ALL = NOPASSWD: /usr/sbin/adduser --gecos [a-zA-Z0-9]* [a-zA-Z0-9]*
</source>
;Remark:This line should be commented out when the students have added them selves.

==File: /home/ny/bin/nybruger==
Create the '''/home/ny/bin''' directory and add the file '''/home/ny/bin/nybruger''' with the following content. (Remember to change mode to executable)
<source lang=bash>
#!/bin/bash
tput clear
echo -e "                        Tilføj bruger"
echo -e "                        ============="
echo -e "\n\n\nIndtast dit ønskede bruger login. Et ord indeholdene bogstaver eller/og tal."
LOOP=1
while test $LOOP -eq 1
do
  echo -en "\nBruger login: "
  read LOGIN
  if echo -n $LOGIN | grep -E "^[0-9A-Za-z]*$"  >/dev/null  2>&1
  then
    if grep $LOGIN /etc/passwd  >/dev/null  2>&1
    then
     echo -e "Det valgte bruger login er allerede i brug!!!"
    else
     LOOP=0
    fi
  else
    echo -e "login navnet skal være ET ord bestående af bogstaver a-z, A-Z eller tal 0-9"
  fi
done

sudo /usr/sbin/adduser $LOGIN
if grep $LOGIN /etc/passwd
then
  COUNT=5
  while test $COUNT -gt 0
  do
    echo -en "\r Bruger $LOGIN oprettet. Sessionen afsluttes om $COUNT sekunder"
    $((COUNT-=1)) 2> /dev/null
    sleep 1
  done
else
COUNT=5
  while test $COUNT -gt 0
  do
    echo -en "\r FEJL: Bruger $LOGIN er IKKE oprettet. Sessionen afsluttes om $COUNT sekunder"
    $((COUNT-=1)) 2> /dev/null
    sleep 1
  done
fi
exit
</source>

=Security=
Change all files to root ownership so the students cant change the script catching other students passwords etc.
<source lang=bash>
chown root:root /home/ny
chown root:root /home/ny/.profile
chown root:root /home/ny/bin
chown root:root /home/ny/bin/nybruger
</source>

[[Category:Linux]]