v2

gistfile1.txt

#!/bin/bash

# This script MUST be run with proper priveleges
# Root/sudo is needed for the chage command!

# Defines the name of the file to be created
# The format is: hostname_date-of-today.csv
filename="$(hostname)_user_password_age_report_$(date '+%Y-%m-%d').csv"

# Creates the destination file and
# prepares the colomns used in the output file
#
# The output format will be:
#
# hostname,user,last changed, age in days
# xzy104,john,2022-01-02,155d,/bin/bash
echo "hostname;username;last changed;password age" > "$filename"

# The loop does the following steps:
# Read /etc/passwd
# Extract all users and shells
# Calculate the password age
# Write data to file
while read -r line;
do

  # Extract the username from line which was read in
  USR=$(echo "$line" | cut -f1 -d:)

  # Extract the shell from line which was read in
  SHLL=$(echo "$line" | rev | cut -d: -f 1 | rev)

  # Get the date of the last password change
  # DOLPC: Date OF the Last Password Change
  DOLPC=$( \
      chage -l "$USR" | \
      head -n 1 | \
      cut -f 2 -d ':' | \
      cut -d ' ' -f 2- | \
      date +"%Y-%m-%d" -f -
    )

  # Calculate the password age
  # PAID: Password Age In Days
  PAID=$(( ( $(date +%s) - $(date --date="$DOLPC" +%s) ) / (60*60*24) ))

  # Write data to file
  {
    echo -n "$(hostname),"; # Hostname
    echo -n "$USR,"         # Username
    echo -n "$DOLPC,"       # Date of the last password age
    echo -n "$PAID,"        # Password age in days
    echo "$SHLL"            # Shell of the user
  }  >> "$filename"
done < /etc/passwd