shell scripting project #1

day02/pam-main.sh

@@ -0,0 +1,153 @@
+#/bin/bash
+#!/usr/bin/bash
+# Date: 10/09/2025
+# This is script for user & group management in linux.
+# Usage: pam-main.sh
+# Author: Bhikesh Khute
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+WHITE='\033[1;37m'
+PURPLE='\033[0;35m' 
+CYAN='\033[0;36m'
+NC='\033[0m'
+echo "------------------------------------------------------"
+echo -e "=======\033[45m Welcome to Login Management System \033[0m======="
+echo "------------------------------------------------------"
+while true; do
+echo -e "${RED}1. Add user${NC}"
+echo -e "${GREEN}2. Delete user${NC}"
+echo -e "${PURPLE}3. Modify user - Add user to multiple groups${NC}"
+echo -e "${CYAN}4. Modify user - Changing Login Shell${NC}"
+echo -e "${YELLOW}5. Modify user - Disable Login${NC}"
+echo -e "${GREEN}6. Modify user - Enable Login${NC}"
+echo -e "${CYAN}7. Modify user - Add user to sudo group${NC}"
+echo -e "${RED}8. Add group${NC}"
+echo -e "${GREEN}9. Backup directories${NC}"
+echo -e "${PURPLE}10. Exit${NC}"
+read -p "Select the option: " choice
+case $choice in 
+	1) 
+	read -p "Enter first and last name of the user(Example - Ramesh Sippy): " fullname #Example - Ramesh Sippy
+	username=`echo $fullname | awk '{print tolower($1 $2)}'` #Output - rameshsippy
+	useradd -c "$fullname" -m -s /bin/bash $username > /dev/null #Redirects output to blackhole instead of screen
+	echo $username:R@nd0mDig!t | chpasswd #Adding Default Password; To be changed after login for security reasons.
+	passwd --expire $username > /dev/null #Password is expired so that on first login itself it can be changed.
+	echo "$username is successfully created in the system"
+	echo "-----------------------------------------------"
+	unset username
+	;;
+        2)
+	awk -F: '$3 >= 1000 {print $1}' /etc/passwd | nl -w1 -s". " #Filtering only normal users
+	read -p "Select user to be deleted: " choice
+	username=$(awk -F: '$3 >= 1000 {print $1}' /etc/passwd | sed -n "${choice}p")
+	deluser --remove-home -q $username
+	echo "$username is successfully deleted from the system"
+	echo "-------------------------------------------------"
+	unset username
+	unset choice
+	;;
+	3)
+	echo "------------------Normal Users List------------------"
+	awk -F: '$3 >= 1000 {print $1}' /etc/passwd | nl -w1 -s". " #Filtering only normal users
+	echo "------------------Group List-------------------------"
+        awk -F: '$3 >= 1000 {print $1}' /etc/group | nl -w1 -s". "
+	read -p "Select the existing user: " choice
+	read -p "Select the group name to be added: " gchoice
+	username=$(awk -F: '$3 >= 1000 {print $1}' /etc/passwd | sed -n "${choice}p")
+	grpname=$(awk -F: '$3 >= 1000 {print $1}' /etc/group | sed -n "${gchoice}p")
+        usermod -aG $grpname $username
+	echo "$username is successfully added to group $grpname"
+	echo "-------------------------------------------------"
+	unset grpname
+	unset username
+	unset choice
+	unset gchoice
+	;;
+        4)
+	echo "------------------Normal Users List------------------"
+	awk -F: '$3 >= 1000 {print $1}' /etc/passwd | nl -w1 -s". " #Filtering only normal users
+	read -p "Select the existing username: " choice
+	username=$(awk -F: '$3 >= 1000 {print $1}' /etc/passwd | sed -n "${choice}p")
+	curr_shell=$(getent passwd "$username" | cut -d: -f7)
+	if [ "$curr_shell" = "/bin/sh" ]; then
+		    chsh -s /bin/bash "$username"
+		    echo "$username's shell is successfully changed to bash"
+		    echo "-------------------------------------------------"
+	elif [ "$curr_shell" = "/bin/bash" ]; then
+		    chsh -s /bin/sh "$username"
+		    echo "$username's shell is successfully changed to sh"
+		    echo "-----------------------------------------------"
+	fi
+	unset username
+	unset curr_shell
+	unset choice
+	;;
+        5)
+	echo "------------------Normal Users List------------------"
+	awk -F: '$3 >= 1000 {print $1}' /etc/passwd | nl -w1 -s". " #Filtering only normal users
+	read -p "Select the existing username: " choice
+	username=$(awk -F: '$3 >= 1000 {print $1}' /etc/passwd | sed -n "${choice}p")
+	if getent passwd "$username" > /dev/null; then
+		echo "Changing $username shell to /usr/sbin/nologin"
+		chsh -s /usr/sbin/nologin "$username"
+		echo "$username's disabled to nologin"
+		echo "-------------------------------"
+	else
+		echo "User $username not found!"
+	fi
+	unset username
+	unset choice
+	;;
+        6)
+        echo "------------------Normal Users List------------------"
+        awk -F: '$3 >= 1000 {print $1}' /etc/passwd | nl -w1 -s". " #Filtering only normal users
+        read -p "Select the existing username: " choice
+	username=$(awk -F: '$3 >= 1000 {print $1}' /etc/passwd | sed -n "${choice}p")
+        if getent passwd "$username" > /dev/null; then
+                echo "Changing $username shell to /bin/bash"
+                chsh -s /bin/bash "$username"
+		echo "$username's shell is successfully activated to bash"
+		echo "---------------------------------------------------"
+        else
+                echo "User $username not found!"
+	fi
+	unset username
+	unset choice
+        ;;
+        7)
+	echo "------------------Normal Users List------------------"
+	awk -F: '$3 >= 1000 {print $1}' /etc/passwd | nl -w1 -s". " #Filtering only normal users
+	read -p "Enter the existing username: " choice
+	username=$(awk -F: '$3 >= 1000 {print $1}' /etc/passwd | sed -n "${choice}p")
+	usermod -aG sudo $username
+	echo "$username is successfully added to sudo group. Enjoy super-privileges!"
+	echo "----------------------------------------------------------------------"
+	unset username
+	unset choice
+	;;
+        8)
+        read -p "Enter the group name to be added: " grpname
+        addgroup $grpname > /dev/null
+	echo "--------------------$grpname is added in the system.------------------"
+	echo " "
+	;;
+        9)
+        mkdir -p /opt/dir_backups
+	read -p "Select the username to intiate the backup: " choice
+	username=$(awk -F: '$3 >= 1000 {print $1}' /etc/passwd | sed -n "${choice}p")
+	read -p "Specify the path of the directory to be backuped up: " dirback
+	tar -cvzf /opt/dir_backups/$username.tar.gz $dirback > /dev/null
+	echo "Backup completed successfully"
+	echo "-----------------------------"
+	unset username
+	unset dirback
+	unset choice
+	;;	
+        10)
+	break;
+	;;
+        *)
+	echo "Invalid option! Exiting the program"
+esac
+done