usertools-elwardthomas

#!/bin/bash
#usertools-elward.thomas
#CIS 2434
#Prof. S.Millichamp

#touch ./tmpfile
tempfile=tmpfile
trap 'rm -f $tempfile' 0 1 2 3 15
#couldn't get this to work....if i remember in basic it was like on error goto cleanup ha
#or in java setting up exception throws and stuff


############### functions #################

help(){
  #display help screen
	echo ""
	echo ""
	echo -e "\t----usertools-elwardthomas------"
	echo ""
	echo ""
	echo -e ""
	echo -e "\t help :\tshows this screen\n"
	echo -e "\t list_systemusers [file_name] :\n\t\t\tlist users in file or default /etc/passwd\n"
	echo -e "\t count_canlogin [file_name] :\n\t\t\tdisplay users with shell ability to login\n"
	echo -e "\t adduser :\n\t\t\tfollow prompts presented to\n\t\t\tadd new user to system\n"
	echo -e "\t batchadd [file_name] [user_name_prefix] [user count] :\n\t\t\tmass user add service\n\t\t\tfile_name for where to store the creation information\n\t\t\tuser count [1-99]\n\t\t\tprefix for easily identifying users"
	echo ""
	echo ""

}


adduser(){
	#general add user function
	
	echo -n "Please enter a Username: "
	read USER_NAME #gets the name
	if [[ -z "${USER_NAME}" ]]; then #checks for shenanigans
		echo "ERROR: Must enter a username --exiting"
		exit 4
	else #continues on
		echo -n "Please enter GECOS [user description [can be left blank]]: "
		read USER_DESC #can be blank
		echo -n "Please enter Shell type for account [use standard format /bin/[shellname] ...default /bin/bash]: "
       	read SHELL_TYPE
       	if [ -z $SHELL_TYPE ]; then #check if blank
       		SHELL_TYPE="/bin/bash" #set to default bash shell
       	fi
       	if ! [[ -e $SHELL_TYPE ]]; then #check if found in /bin/ directory
       		echo "ERROR: there is no record of that shell existing"
       		exit 2
       	fi 
        	#echo "newuser_$USER_NAME::$SHELL_TYPE::$USER_DESC" #testing variables
        	
       	touch "newuser-$USER_NAME" #create new user file
       	echo "$USER_NAME::::$USER_DESC:/home/$USER_NAME:$SHELL_TYPE" >> newuser-$USER_NAME #populate new user file
       	#format reminder
       	#username:password:pw_uid:pw_gid:pw_gecos:pw_dir:pw_shell
       	
       	# need sudo for this i don't remember if it was necessary condition...
       	# mkdir "/home/$USER_NAME"
       	exit 0
    fi
	
}

batchadd(){
	
	FILE=$FIRST_ARG
	USER_PREFIX=$SEC_ARG
	USER_COUNT=$THIRD_ARG
	SHELL_TYPE="/bin/bash"
	if [[ $USER_COUNT -gt 99 ]]; then #check user count
		echo "ERROR: Cannot create more than 99 users"
		exit 1
	fi
	if [[ -a $FILE ]]; then #check if file exists
		echo "ERROR: Cannot Overwrite existing file(s)"
		exit 2
	fi
	
	for ((i=1; i <= $USER_COUNT; i++))
   		do
        	if [ $i -lt 10 ]; then        # If $i is smaller than 10
            	TEMP_USER="username0$i"    # set username format with 01-09
            	TEMP_DESC="username 0$i"
        	else
        	    TEMP_DESC="username $i"
        	    TEMP_USER="username$i"     # set username format for 10-99
        	fi

        	echo "$TEMP_USER::::$TEMP_DESC:/home/$TEMP_USER:$SHELL_TYPE" >> "$tempfile"
        	
        	#echo $i
        	#sleep 20 #timer to try and interrupt see trap working....but not
        	
	done
	cat "$tempfile" >> $FILE
	rm -f "$tempfile"
	exit 0
}

can_login(){
	
	echo  -n "Total Users with shell login ability: "
	awk -F':' '{if ($7 != "/sbin/nologin") print $1}' $FIRST_ARG > $tempfile 
	
	#awk -F':' '{if ($7 != "/bin/false") print $1}' $FIRST_ARG > $tempfile #ubuntu ver
	#awk -F':' '{if ($7 != "/usr/bin/false") print $1}' $FIRST_ARG > $tempfile #osx ver
	
	#checks the 7th : as to whether or not it contains text
	#then prints those users to a file...i wasn't sure if i was able to create an itterator
	#to keep track of the amount listed in a single awk line? still kinda confused by what it does
	#because i found the line below to basically get a line count of the file which is the output
	#of the first awk command....
	
	awk 'BEGIN{i=0}{i++;}END{print i}' $tempfile
	
	rm -f $tempfile #removes tmp file created 
	
	#
	
	exit 0
}

error_file(){ #checks if files exist exits if they do not...
	if ! [ -a $FIRST_ARG ]; then
		echo "error: file path was not correct"
		exit 1
	fi
}

list_users(){

	awk -F':' '{ if ($3 < 500) print $1 " : " $5 }' $FIRST_ARG | sort #if uid level less than 500 we print it 
	exit 0

}

############### end functions #################



############### main ###############

FIRST_ARG=$2 #converting params into variables because i wasnt sure how bash handles 
SEC_ARG=$3 # passing things into functions.....
THIRD_ARG=$4

    case "$1" in #case statement for selecting user entered params
		
		help) help ; exit 0;; #run help
		
		loggedin) who | more;; # shows users on system
		
		list_systemusers) #list people below 500
			if [ -z $FIRST_ARG ]; then
				FIRST_ARG="/etc/passwd"
			fi
			error_file
			list_users;; 
		
		adduser) adduser;; #hm jump to function
		
		batchadd) batchadd;; #jump to function
		
		count_canlogin) # count the users who have ability to login
			 
			if [ -z $FIRST_ARG ]; then
				FIRST_ARG="/etc/passwd"
			fi
			error_file
			can_login ;;
		
		*) help; exit 1;;	

    esac