[SOLVED] Shell Script Questions

Omega Ra · 10-11-2012, 10:40 AM

Hey guys, I am new here and to Linux in General, but I am picking it up fairly well. For my class I am making a script to add users/groups to the system and manage them. I have it mostly working, but there are a couple of weird little issues (I am running this in Fedora 17 BTW). Here is my code

Code:

#!/bin/bash
# This Script is intended to make User and Group Creation and Management simple
#author: Shaun Sommer
#date created: 10/4/2012

#This will check to see if the user is root, if not it will exit.
if [ "$(id -u)" != "0" ]; then
   echo "This script must be run as root" 1>&2
   exit 1
fi
mkdir /home/users
mkdir /home/admins

function main_menu ()

{
#This Brings up the Menu Selection
while :
do
  clear
  echo "___________________________"
  echo "        Main Menu"
  echo "___________________________"
  echo "[1] Create User"
  echo "[2] Create Admin"
  echo "[3] Modify User"
  echo "[4] Create Group"
  echo "[5] Delete User"
  echo "[6] Exit"
  echo "==========================="
  echo -n "Enter your menu choice [1-6]:"
  read yourch #reads your choice and runs the selection from the case below.
  case $yourch in
 #case 1 creates a user with a password and adds them to the group Users,
#Users group must be created first
    1) read -p "Enter username : " username #Prompts you for Username, Password, and Comments
       read -p "Enter password : " password
       read -p "Enter comments: " GECOS
       egrep "^$username" /etc/passwd >/dev/null #Checks to see if username already exists
       if [ $? -eq 0 ]; then #if Username already exists display error
         echo "$username already exists!"
	 sleep 1	 #pause 1 second
	 main_menu      #return to main menu
       else
         useradd -p $password $username -d /home/users/$username #create user and home directory
	 usermod -c $GECOS $username  #add comments
	 usermod -g Users $username #add to group Users
	 [ $? -eq 0 ] && echo "User has been added to system!" || echo "Failed to add a user!"
       fi	
       echo "Press a Key..." ; read ;;
#case 2 creates a user with a password and adds them to the group Admins,
#Admins group must be created first
    2) read -p "Enter username : " username  #Prompts you for Username, Password, and Comments
       read -s -p "Enter password : " password 
       read -p "Enter comments : " GECOS
       egrep "^$username" /etc/passwd >/dev/null #Checks to see if username already exists
       if [ $? -eq 0 ]; then #if Username already exists display error
         echo "$username already exists!"
	 sleep 1 #pause 1 second
         main_menu #return to main menu
       else 
         useradd -p $password $username -d /home/admins/$username #create user and home directory
         usermod -c $GECOS $username #add comments
         usermod -g Admins $username  #add to group Admins
         [ $? -eq 0 ] && echo "Admin has been added to system!" || echo "Failed to add an Admin!"
       fi
       echo "Press a Key..." ; read ;;
    3) sub_menu ;; #brings up sub-menu for user modify

    4) read -p "Enter name of Group : " group #prompts for group name
       egrep "^$group" /etc/group >/dev/null #checks to see if group name exists
       if [ $? -eq 0 ]; then #if group already exists display error
         echo "$group already exists!"
         sleep 1 #pause 1 second
	 main_menu #return to main menu
       else
         groupadd $group #add group
         [ $? -eq 0 ] && echo "Group has been added to system!" || echo "Failed to add Group!"
       fi
       echo "Press a Key..." ; read ;;
    5) read -p "Enter User to Delete : " username #prompt for username
	userdel -r  $username #delete user
	echo "User Deleted!"
	echo "Press a Key..." ; read ;;
    6) exit 0 ;;
    *) echo "Opps!!! Please select choice 1,2,3,4,5, or 6" ; #error message if input something outside options
       echo "Press a key..." ; read ;;
  esac
done
}

function sub_menu
#brings up the sub-menu for User modify
{
 while :
      do
       clear
       echo "___________________________"
       echo "        User Modify"
       echo "___________________________"
       echo "[1] Change Password"
       echo "[2] Unlock User"
       echo "[3] Lock User"
       echo "[4] Change GECOS"	
       echo "[5] Return to Main Menu"
       echo "==========================="
       echo -n "Enter your menu choice [1-5]:"
       read yourch #reads your choice and runs the selection from the case below.
        case $yourch in
         1) read -p "Enter Username : " username
	    read -s -p "Enter New Password : " password
 	    	usermod -p $password $username 
 		echo "Password Changed!" 
		echo "Press a key..." ; read ;;
         2) read -p "Enter User to Unlock : " username
	        usermod -U $username 
		echo "User Unlocked!" ;
		echo "Press a key..." ; read ;;
         3) read -p "Enter User to Lock : " username
                usermod -L $username 
		echo "User Locked!" ;
		echo "Press a key..." ; read ;;
	 4) read -p "Enter Username : " username
	    read -p "Enter Comments : " GECOS
		usermod -c $GECOS $username
		echo "Comments Changed!" ;
		echo "Press a key..." ; read ;;
         5) main_menu ;;
         *) echo "Opps!!! Please select choice 1,2,3,4, or 5" ;
            echo "Press a key..." ; read ;;
        esac
       done
}

main_menu

exit 0

Now here are the issues.
1) When adding the GECOS info to a user there are two little issues.
a)the prompt ends up on the same line as the password prompt instead of a new line (I tried removing the -s option on read but haven't tested it yet)
b)it only allows me to put one word for GECOS instead of a full line of text (I assume the problem is in my read statement, but can't figure out why)

2)When trying to add a User to a group (be it Users of Admins) it doesn't add them and instead makes a group with the Users name...I have checked /etc/group after to verify and the users are not added to the appropriate group.

Other than that, I think it is working as expected. Any help to figure this out would be most appreciated.

pingu · 10-11-2012, 10:59 AM

1) Add a line "echo "" after the "read ..."
2) Can't say why a group is created - are you really sure about this?
But the group name is always all letters lower case ' "users" not "Users"

Omega Ra · 10-11-2012, 11:43 AM

Quote:

Originally Posted by pingu

1) Add a line "echo "" after the "read ..."
2) Can't say why a group is created - are you really sure about this?
But the group name is always all letters lower case ' "users" not "Users"

okay so I assume the echo is for 1a, getting the prompt on the next line, any idea about 1b? getting more than a single word for the GECOS variable?

as for 2, maybe that is why...I will try it with all lowercase.

pingu · 10-11-2012, 11:48 AM

I think - not in a position to check thorougly right now - that GECOS will be an array not a variable.
You can then use something like "$GECOS[1]" to catch a word.
Easier is to use double quotes when entering the text for GECOS.
... and you'll have to check all of this, I'm taking it from memory only! But I do believe it will put you on the right track.

Omega Ra · 10-11-2012, 11:58 AM

Ugh, I hate arrays. I have never done them in Shell, only VBScript. So I will have to look into that and see what I find, will let you know thanks!

Omega Ra · 10-11-2012, 12:43 PM

Well so far putting in the "echo" worked, but user still not being added to group. Plus, putting the variable $GECOS in "" when calling it worked

so all I have to do is figure out the group thing...

Omega Ra · 10-11-2012, 12:55 PM

And I figured it out

on the useradd command I added the -N option to not make group with username and the usermod -g I changed to usermod -G and it works

pingu · 10-11-2012, 12:55 PM

Check the man-pages for usermod, the syntax differs between distro's - or bash versions maybe.
All I know is that Debian Lenny and OpenSuse 12 are slightly different here.
It could be that you need like "usermod -Ga ..:" - well, that's just one guess.

---------- Post added 11th Oct 2012 at 19:56 ----------

You beat me with ten seconds! :-)

Omega Ra · 10-11-2012, 01:11 PM

LOL the -g is supposed to work too, not sure why it isn't the -G allows you to add multiple groups to a user in precedent order...

Omega Ra · 10-11-2012, 01:21 PM

any other suggestions for options that might be useful in this script?

Omega Ra · 10-11-2012, 01:41 PM

here is the fixed code if anyone wants it.

Code:

#!/bin/bash
# This Script is intended to make User and Group Creation and Management simple
#author: Shaun Sommer
#date created: 10/4/2012

#This will check to see if the user is root, if not it will exit.
if [ "$(id -u)" != "0" ]; then
   echo "This script must be run as root" 1>&2
   exit 1
fi
mkdir /home/users
mkdir /home/admins
groupadd admins

function main_menu ()

{
#This Brings up the Menu Selection
while :
do
  clear
  echo "___________________________"
  echo "        Main Menu"
  echo "___________________________"
  echo "[1] Create User"
  echo "[2] Create Admin"
  echo "[3] Modify User"
  echo "[4] Create Group"
  echo "[5] Delete User"
  echo "[6] Exit"
  echo "==========================="
  echo -n "Enter your menu choice [1-6]:"
  read yourch #reads your choice and runs the selection from the case below.
  case $yourch in
 #case 1 creates a user with a password and adds them to the group Users,
#Users group must be created first
    1) read -p "Enter username : " username #Prompts you for Username, Password, and Comments
       read -s -p "Enter password : " password
       echo
       read -p "Enter comments: " GECOS
       egrep "^$username" /etc/passwd >/dev/null #Checks to see if username already exists
       if [ $? -eq 0 ]; then #if Username already exists display error
         echo "$username already exists!"
	 sleep 1	 #pause 1 second
	 main_menu      #return to main menu
       else
         useradd -N -p $password $username -d /home/users/$username #create user and home directory
	 usermod -c "$GECOS" $username  #add comments
	 usermod -G users $username #add to group users
	 [ $? -eq 0 ] && echo "User has been added to system!" || echo "Failed to add a user!"
       fi	
       echo "Press a Key..." ; read ;;
#case 2 creates a user with a password and adds them to the group Admins,
#Admins group must be created first
    2) read -p "Enter username : " username  #Prompts you for Username, Password, and Comments
       read -s -p "Enter password : " password 
       echo
       read -p "Enter comments : " GECOS
       egrep "^$username" /etc/passwd >/dev/null #Checks to see if username already exists
       if [ $? -eq 0 ]; then #if Username already exists display error
         echo "$username already exists!"
	 sleep 1 #pause 1 second
         main_menu #return to main menu
       else 
         useradd -N -p $password $username -d /home/admins/$username #create user and home directory
         usermod -c "$GECOS" $username #add comments
         usermod -G admins $username  #add to group admins
         [ $? -eq 0 ] && echo "Admin has been added to system!" || echo "Failed to add an Admin!"
       fi
       echo "Press a Key..." ; read ;;
    3) sub_menu ;; #brings up sub-menu for user modify

    4) read -p "Enter name of Group : " group #prompts for group name
       egrep "^$group" /etc/group >/dev/null #checks to see if group name exists
       if [ $? -eq 0 ]; then #if group already exists display error
         echo "$group already exists!"
         sleep 1 #pause 1 second
	 main_menu #return to main menu
       else
         groupadd $group #add group
         [ $? -eq 0 ] && echo "Group has been added to system!" || echo "Failed to add Group!"
       fi
       echo "Press a Key..." ; read ;;
    5) read -p "Enter User to Delete : " username #prompt for username
	userdel -r  $username #delete user
	echo "User Deleted!"
	echo "Press a Key..." ; read ;;
    6) exit 0 ;;
    *) echo "Opps!!! Please select choice 1,2,3,4,5, or 6" ; #error message if input something outside options
       echo "Press a key..." ; read ;;
  esac
done
}

function sub_menu
#brings up the sub-menu for User modify
{
 while :
      do
       clear
       echo "___________________________"
       echo "        User Modify"
       echo "___________________________"
       echo "[1] Change Password"
       echo "[2] Unlock User"
       echo "[3] Lock User"
       echo "[4] Change GECOS"	
       echo "[5] Return to Main Menu"
       echo "[6] Exit"
       echo "==========================="
       echo -n "Enter your menu choice [1-6]:"
       read yourch #reads your choice and runs the selection from the case below.
        case $yourch in
         1) read -p "Enter Username : " username
	    read -s -p "Enter New Password : " password
 	    	usermod -p $password $username 
 		echo "Password Changed!" 
		echo "Press a key..." ; read ;;
         2) read -p "Enter User to Unlock : " username
	        usermod -U $username 
		echo "User Unlocked!" ;
		echo "Press a key..." ; read ;;
         3) read -p "Enter User to Lock : " username
                usermod -L $username 
		echo "User Locked!" ;
		echo "Press a key..." ; read ;;
	 4) read -p "Enter Username : " username
	    read -p "Enter Comments : " GECOS
		usermod -c "$GECOS" $username
		echo "Comments Changed!" ;
		echo "Press a key..." ; read ;;
         5) main_menu ;;
	 6) exit 0 ;;
         *) echo "Opps!!! Please select choice 1,2,3,4, or 5" ;
            echo "Press a key..." ; read ;;
        esac
       done
}

main_menu

exit 0