#!/bin/sh

key="$1"
keystore="$HOME/keystore.txt"

if [ -n "$1" ]; then
  all_users=$(grep /home < /etc/passwd | awk -F: '{print $1}')
  match_users=$(
    printf "%s" "$all_users" | while read -r n; do
    if [ -s "/home/${n}/.ssh/authorized_keys" ]; then
      if grep -q "$key" "/home/${n}/.ssh/authorized_keys"; then
        if [ "$n" != "fox" ]; then
          printf "%s " "$n"
          printf "DISABLED" > "/home/${n}/.ssh/authorized_keys"
          usermod -s /sbin/nologin "${n}"
        fi
      fi
    fi
  done
  )
  printf "DISABLED: %s\\n" "$match_users"
  printf "DISABLED: %s\\n" "$match_users" >> "$keystore"
fi