Bash script for adding users is running but not adding users

Gren · 04-26-2012, 10:58 PM

Hi all

My friend and I are trying to write a script for a Fedora system which adds users by reading from a text file with the layout username

assword:groupname:fullname. The script seems to run as it displays the about and help text from their respective files, however no new users are being added when we check /etc/passwd/.

Code:

#!/bin/bash

#script to create user with username,password,groupname,fullname

if [ $(id -u) -ne 0 ]; then

#this above line will check the id not equal to 0

   echo "only root users may add a user to the system"
exit 1
fi

#this will display information about the script file when it is executed

 if [ $# -ne 1 ]; then
cat about.txt
exit 0

#here when -h is typed with script then it will display text in the helpfile.txt file and give information about using the script

fi
if [ $1 == "-h" ]; then
cat helpfile.txt
exit 1
fi

#this will make the string divided by ':'

sed 's/':'/ /g' $1 >list_user.txt

# read the userlist in format: username,password,groupname,fullname

cat list_user.txt | while read uname password gname fullname
do

#encrypting the password and assigned to variable

    pass=$(perl -e 'print crypt($ARGV[0], "password")' $password)

#assiging the length of password to variable LEN

    LEN=$(echo ${#password})
    egrep -w  "^$uname" /etc/passwd >/dev/null

# this is to search the username in /etc/passwd and send output to null file

#if the username exists then it wil send the error report to error_report.txt

   if [ $? -eq 0 ]; then
         echo "$uname exists! try a different user name" >>error_report.txt
    continue

#if username does not exist then it will continue to the next iteration

   fi

# here we check the length of password is in between 9 an 12

if [[( $LEN -lt 9) || ($LEN -gt 12)]] ;  then
              echo " user with $uname: length of the password is not in between 9 and 12">>error_report.txt
       continue

#if password length is in between 9 and 12 then it will contiue to the next iteration

   fi
              egrep -w  "^$gname" /etc/group >/dev/null
          if [ $? -ne 0 ]; then

#if above command executed sucessfully then script will groupadd

                 groupadd "$gname"
           fi

#to create user with username,password,groupname,fullname

       useradd -p "$pass" -g "$gname" -c "$fullname" $uname
                 uid=$(grep -i ${uname} /etc/passwd | cut -d: -f3)

#we are assigning the 3rd field of the ouput of username from /etc/passwd

                 gid=$(grep -i ${uname} /etc/passwd | cut -d: -f4)

#we are assigning the 4th field of the output of username from /etc/passwd

       if [ $? -eq 0 ];then

# if the useradd cmd executed succesfully then userdetails are redirected to userdetails.txt

              echo $uname";"$uid";"$gname";"$gid";"$(date)";"$fullname>>userdetails.txt
       echo "$uname user added "
        else
           echo "user with $uname not added try to find error">>error_report.txt

#if useradd program is not added succesfull then error will be redirected to errorr_report

       fi
done

millgates · 04-27-2012, 03:15 AM

1)

Code:

cat about.txt

this will only work when about.txt is in the current directory. You can also use bash here document here

Code:

cat <<- END_OF_DOCUMENT
	text ...
END_OF_DOCUMENT

2)

Code:

sed 's/':'/ /g' $1 >list_user.txt

You can't do this with sed. sed will search for the file $1 and try to read it. To pass string to sed, use either echo,

Code:

echo "$1" | sed '...'

or here string

Code:

sed '...' <<< "$1"

3)

Code:

cat list_user.txt | while read uname password gname fullname

So, you write the argument into file and then read it again? May I ask why?
Also, why the loop? The file will only contain one line.

4)

Code:

LEN=$(echo ${#password})

OK, why the echo? Why don't you just write

Code:

LEN="$(#password)"

5)

Code:

if [[( $LEN -lt 9) || ($LEN -gt 12)]] ;  then echo "..."
    ...
fi

You can also use bash arithmetics:

Code:

if (( (LEN < 9) || (LEN > 12) )); then
    ...
fi

or even

Code:

(( (LEN < 9) || (LEN > 12) )) && (echo ""; continue)
fi

6)

Code:

       useradd -p "$pass" -g "$gname" -c "$fullname" $uname
                 uid=$(grep -i ${uname} /etc/passwd | cut -d: -f3)
                 gid=$(grep -i ${uname} /etc/passwd | cut -d: -f4)
       if [ $? -eq 0 ];then
           ...
# if the useradd cmd executed succesfully then userdetails are redirected to userdetails.txt

No, actually the assignments will overwrite the exit status of useradd.

7) try to run your script with -x switch

8) did you look into your log file?

lithos · 04-27-2012, 03:53 AM

Quote:

Originally Posted by Gren

Hi all

Code:

.......

#to create user with username,password,groupname,fullname

       useradd -p "$pass" -g "$gname" -c "$fullname" $uname
                 uid=$(grep -i ${uname} /etc/passwd | cut -d: -f3)

This line is maybe also trouble, because I don't find it using this way with specifying the option -p pass.
Leave that out and use another command:

Code:

passwd "username"

but then you will need to enter the password to the prompt.
Take a look here for the script example.

good luck