born2beroot

Operating system

Debian 11.6

Requirements

• No graphical interface

• 2 encrypted partitions using LVM

• SSH service only running on port 4242

• Impossible to connect using SSH as root

• Configure operating system with the UFW

hostname

• Login ending with 42

Users

• Root user

• A user with the login as username, it has to belong to the user42 and sudo groups

pwd security

Requirements	Description
Expiration	Every 30 days
Min number of days allowed before modification	2
Warning message	7 days before expiration
Length	At least 10 characters
Composition	An uppercase letter, a lowercase letter and a number
Forbidden	More than 3 consecutive identical characters, include the name of the user
New password	Must have at least 7 characters that aren't a part of the former password

Configuration for sudo group

• Authentication of sudo caused by incorrect password is limited to 3 attempts.

• Display message if there is an error caused by an incorrect password.

• Archive every action of sudo (inputs and outputs). The log file has to be saved in: /var/log/sudo/

• TTY mode has to be enabled

• Paths that can be used by sudo must be restricted.

monitoring.sh

Developed in bash, will display some information on all terminals every 10 min. No error must be visible.

Information for the script
The architecture of your operating system and its kernel version
Number of physical processors
Number of virtual processors
Current available RAM on your server and its utilization rate as a percentage
Current available memory on your server and its utilization rate as a percentage
Current utilization rate of your processors as a percentage
Date and time of the last reboot
Whether LVM is active or not
Number of active connections
Number of users using the server
IPv4 address of your server and its MAC address
Number of commands executed with the sudo program.

Steps

• Download and check debian distro:

echo '224cd...e6f51  debian-11.6.0-amd64-netinst.iso' | sha512sum --check
debian-11.6.0-amd64-netinst.iso: OK

monitoring script

# **************************************************************************** #
#                                                                              #
#                                                         :::      ::::::::    #
#    monitoring.sh                                      :+:      :+:    :+:    #
#                                                     +:+ +:+         +:+      #
#    By: echavez- <echavez-@student.42.fr>          +#+  +:+       +#+         #
#                                                 +#+#+#+#+#+   +#+            #
#    Created: 2023/01/31 12:22:02 by echavez-          #+#    #+#              #
#     Updated: 2023/01/31 12:26:44 by echavez-         ###   ########.fr       #
#                                                                              #
# **************************************************************************** #

#!/bin/bash

function ft_ram()
{
    # RAM INFO

    ## Variables
    local _free=$(free -m | grep Mem | awk '{print $3}')
    local _total=$(free -m | grep Mem | awk '{print $2}')
    local _usage_percent=$(free -m | grep Mem | awk '{printf("%.2f"), $3 / $2 * 100}')

    ## Return formated info
    echo "${_free}/${_total}MB (${_usage_percent}%)"
}

function ft_mem()
{
    # DISK MEMORY INFO

    ## Disk description lines
    local _mem_mb=$(df -Bm | grep '^/dev/' | grep -v '/boot$') # megas
    local _mem_gb=$(df -Bg | grep '^/dev/' | grep -v '/boot$') # gigas

    ## Variables
    local _free=$(echo "$_mem_mb" | awk '{free_mem += $4} END {print free_mem}')
    local _total=$(echo "$_mem_gb" | awk '{total_mem += $2} END {print total_mem}')
    local _usage_percent=$(echo "$_mem_mb" | awk '{used_mem += $3} {total_mem += $2} END \
    	  		      	       	      {printf("%.2f"), used_mem / total_mem * 100}')

    ## Return formated info
    echo "${_free}/${_total}GB (${_usage_percent}%)"
}

architecture=$(uname -a)
phy_proc=$(grep "^physical id" /proc/cpuinfo | sort -u | wc -l)
vir_proc=$(grep "^processor" /proc/cpuinfo | wc -l)
av_ram=$(ft_ram)
av_mem=$(ft_mem)
cpu_load=$()
last_reboot=$()
lvm_active=$(lsblk | grep -m1 lvm | awk '{if ($1) {print "yes"} else {print "no"} }')
active_connections=$()
active_users=$()
ip_mac=$()
sudo_commands=$(sudo grep 'sudo:session' /var/log/auth.log | grep -v 'session closed\|COMMAND' | wc -l)

wall "    #Architecture: $architecture
    #CPU physical: $phy_proc
    #vCPU: $vir_proc
    #Memory Usage: $av_ram
    #Disk Usage: $av_mem
    #CPU Load: $cpu_load
    #Last boot: $last_reboot
    #LVM use: $lvm_active
    #Connections TCP: $active_connections
    #User log: $active_users
    #Network: $ip_mac
    #Sudo: $sudo_commands cmd"