#! /usr/bin/env sh

#############################################################################
#
# Usage:
# * Run it as user: ./usr/local/bin/dynmotd
# * Run it at user login:
# <file bash /etc/profile>
#   /usr/local/bin/dynmotd
# </file>
# * Or set a cron job with a privileged user (access log files, ...)
# <file bash /etc/cron.d/dynmotd>
#   */30 * * * * root rm -f /etc/motd && /usr/local/bin/dynmotd > /etc/motd
# </file>
#############################################################################

#### Colors definition
BLACK='\033[30;40m'
RED='\033[0;31m'
REDB='\033[1;31m'
GREEN='\033[1;32m'
YELLOW='\033[1;33m'
BLUE='\033[34;40m'
MAGENTA='\033[0;35m'
CYAN='\033[36;40m'
WHITE='\033[0;37m'
WHITEB='\033[1;37m'
RESET='\033[0m'

## Return the state of processes passed in parameters
# process_info $PROCESS_LIST_TO_MONITOR $MESSAGE
process_info() {
  local PROCESS_LIST="${1}"
  local MSG="${2}"

  for PROCESS in ${PROCESS_LIST}; do
    MSG="${MSG}${MAGENTA}+ "
    if (ps ax | grep -v grep | grep ${PROCESS} > /dev/null); then
      MSG="${MSG}${WHITEB}${PROCESS}${RESET} [ ${GREEN}RUNNING${RESET} ] "
    else
      MSG="${MSG}${WHITEB}${PROCESS}${RESET} [ ${REDB}NOT RUNNING${RESET} ] "
    fi
  done

  printf '%b' "${MSG}"
}

## Return the listening socket
# service_info $PORT_LIST_TO_MONITOR $MESSAGE
service_info() {
  local PORT_LIST="${1}"
  local MSG="${2}"

  for PORT in ${PORT_LIST}; do
    MSG="${MSG}${MAGENTA}+ "
    # If a port listen
    if (netstat -lnt|grep -m1 ${PORT} > /dev/null); then
      # Example: "tcp/127.0.0.1:25"
      MSG="${MSG}${GREEN}$(netstat -lnt|grep -m1 ${PORT}|awk '{print $1"/"$4}')${RESET} "
    else
      # Example: "22: NOT LISTENING"
      MSG="${MSG}${REDB}${PORT}: NOT LISTENING${RESET} "
    fi
  done

  printf '%b' "${MSG}"
}

## Return the number of occurrence a pattern is present in a file
# and a color (red:>0, green:=0)
occur_num() {
  local GREP_PAT="${1}"
  local FILE="${2}"

  NUM=$(grep "${GREP_PAT}" "${FILE}" | wc -l)
  if [ "${NUM}" = "0" ]; then
    MSG="${GREEN}${NUM}"
  else
    MSG="${REDB}${NUM}"
  fi

  printf '%b' "${MSG}"
}


#+++++++++++++++++++: System Data :+++++++++++++++++++
HOSTNAME=$(hostname)
NET_ADDR=$(hostname -I)
KERNEL_VER=$(uname -r)
UPTIME=$(uptime | sed 's/.*up ([^,]*), .*/1/')
CORE_NUMBER=$(grep "model name" /proc/cpuinfo | wc -l)
CPU_MODEL=$(grep -m1 "model name" /proc/cpuinfo | awk -F: '{print $2}')
MEM_FREE=$(grep MemFree /proc/meminfo | awk '{print $2}')
MEM_TOTAL=$(grep MemTotal /proc/meminfo | awk '{print $2}')
SWAP_FREE=$(grep SwapFree /proc/meminfo | awk '{print $2}')
SWAP_TOTAL=$(grep SwapTotal /proc/meminfo | awk '{print $2}')

#++++++++++++++++++++: User Data :++++++++++++++++++++++
USERNAME=$(whoami)
USER_SESSION=$(who | grep $USER | wc -l)
PROC_COUNT=$(ps -Afl | wc -l)
PROC_COUNT=$(expr $PROC_COUNT - 5)
# The "ulimit" from sh don't support the -u option
PROC_LIMIT=$(ulimit)

#++++++++++++: Authentication Information :+++++++++++++
# Get only one "auth.log" file path, the most recent
# Simpliest way to get it?
AUTH_LOG_FILE=$(find /var/log -iname 'auth.log' -type f -printf '%TY-%Tm-%Td_%TT %p\n' | sort -r | tail -n1 | cut -d' ' -f2)
SSH_USER_LOGIN=$(grep 'session opened' "${AUTH_LOG_FILE}" | awk '/sshd/' | awk "/${USERNAME}/" | wc -l)


MOTD_ORIG='/etc/motd.orig'
# If an original Motd exist, print it
if [ -f ${MOTD_ORIG} ]; then
  printf "%b" "${RESET}${MAGENTA}+++++++++++++++++++++++: ${WHITE}MoTD${MAGENTA} :++++++++++++++++++++++++${RESET}"
  while read -r line; do
    printf '\n%s' "${line}"
  done < ${MOTD_ORIG}
fi



printf "%b" "\n${RESET}${MAGENTA}+++++++++++++++++++: ${WHITE}System Data${MAGENTA} :+++++++++++++++++++++${RESET}
${MAGENTA}+ ${WHITE}Hostname\t${MAGENTA}= ${GREEN}${HOSTNAME}
${MAGENTA}+ ${WHITE}Addresses\t${MAGENTA}= ${GREEN}${NET_ADDR}
${MAGENTA}+ ${WHITE}Kernel\t${MAGENTA}= ${GREEN}${KERNEL_VER}
${MAGENTA}+ ${WHITE}Uptime\t${MAGENTA}=${GREEN}${UPTIME}
${MAGENTA}+ ${WHITE}CPU\t\t${MAGENTA}= ${GREEN}${CORE_NUMBER}x${CPU_MODEL}
${MAGENTA}+ ${WHITE}Memory\t${MAGENTA}= ${GREEN}${MEM_FREE}(free)/${MEM_TOTAL}(total) kB
${MAGENTA}+ ${WHITE}Swap\t\t${MAGENTA}= ${GREEN}${SWAP_FREE}(free)/${SWAP_TOTAL}(total) kB"


printf "%b" "\n${RESET}${MAGENTA}++++++++++++++++++++: ${WHITE}User Data${MAGENTA} :++++++++++++++++++++++${RESET}
${MAGENTA}+ ${WHITE}Username\t${MAGENTA}= ${GREEN}${USERNAME}
${MAGENTA}+ ${WHITE}Sessions\t${MAGENTA}= ${GREEN}${USER_SESSION}
${MAGENTA}+ ${WHITE}Processes\t${MAGENTA}= ${GREEN}$PROC_COUNT of ${PROC_LIMIT} MAX"


printf '%b' "\n${MAGENTA}++++++++++++: ${WHITE}Authentication Information${MAGENTA} :+++++++++++++${RESET}"
## Count the number of session for all standard's user (with a home/)
#for SSH_USER in `ls -1 /home/`; do
#echo -e "${MAGENTA}+    ${WHITE}SSH login ${MAGENTA}= ${GREEN}`grep 'session opened' "${AUTH_LOG_FILE}" | awk '/sshd/' | awk "/${SSH_USER}/" | wc -l` times this week ("${SSH_USER}")"
##echo -e "${MAGENTA}+    ${WHITE}SSH login ${MAGENTA}= ${GREEN}`grep 'session opened' "${AUTH_LOG_FILE}".1 | awk '/login/' | awk "/${SSH_USER}/" | wc -l` times this week ("${SSH_USER}")"
#done

# Count the number of failed ssh authentication
SSH_FAIL_LOGIN=$(occur_num 'sshd.*Failed' "${AUTH_LOG_FILE}")
printf '%b' "\n${MAGENTA}+ ${WHITE}SSH fail\t${MAGENTA}= ${SSH_FAIL_LOGIN} fail(s) this week"
# Count the number of failed sudo authentication
SUDO_FAIL=$(occur_num 'sudo.*authentication failure' "${AUTH_LOG_FILE}")
SUDO_3_FAIL=$(occur_num 'sudo.*3 incorrect password' "${AUTH_LOG_FILE}")
printf '%b' "\n${MAGENTA}+ ${WHITE}Sudo fail\t${MAGENTA}= ${GREEN}${SUDO_FAIL} fail(s) this week
${MAGENTA}+ ${WHITE}Sudo 3 fails\t${MAGENTA}= ${GREEN}${SUDO_3_FAIL} fail(s) this week"


printf '%b' "\n${MAGENTA}++++++++++++++++++++: ${WHITE}Disk Usage${MAGENTA} :+++++++++++++++++++++${RESET}"
# Root partition
# Replace by rootfs in few kernel version
DISK_USAGE=$(df | grep -m1 "/$" | awk '{print $5}')
printf '%b' "\n${MAGENTA}+ ${WHITEB}/${RESET}\t[ ${DISK_USAGE} ] "

# Other partition
for PART in /boot /home /opt /tmp /usr /var /var/lib/vz; do
  # "/...$" : $ to grep only the mount point and not sub-directories (/var: OK; /mnt/temp: nOK)
  if (df | grep "${PART}$" > /dev/null); then
    DISK_USAGE=$(df | grep "${PART}$" | awk '{print $5}')
    printf '%b' "\n${MAGENTA}+ ${WHITEB}${PART}${RESET}\t[ ${DISK_USAGE} ] "
  fi
done


printf '%b' "\n${MAGENTA}+++++++++++++++++++: ${WHITE}Service Info${MAGENTA} :++++++++++++++++++++${RESET}"

## IF POSTFIX
MSG=$(process_info "postfix" '')
MSG=$(service_info "25" "${MSG}")
printf '%b' "\n${MSG}"
## FI POSTFIX

## Service need a warning if running
YELLOW_SERVICE='tmux screen glances htop automysqlbackup vzdump puppet aptitude'
for SERVICE in ${YELLOW_SERVICE}; do
  if (ps ax | grep -v grep | grep ${SERVICE} > /dev/null); then
    printf '%b' "\n${MAGENTA}+ ${WHITEB}${SERVICE}${RESET} [ ${YELLOW}RUNNING${RESET} ]"
  fi
done


#echo -e "${MAGENTA}+++++++++++++: ${RED}Maintenance Information${MAGENTA} :+++++++++++++++${RESET}
#${MAGENTA}+${RED}""
#echo -e "${MAGENTA}+++++++++++++++++++++++++++++++++++++++++++++++++++++++${RESET}"