#!/usr/bin/env bash

# Pi-hole: A black hole for Internet advertisements
# (c) 2017 Pi-hole, LLC (https://pi-hole.net)
# Network-wide ad blocking via your own hardware.
#
# Controller for all pihole scripts and functions.
#
# This file is copyright under the latest version of the EUPL.
# Please see LICENSE file for your rights under this license.

readonly PI_HOLE_SCRIPT_DIR="/opt/pihole"

# setupVars and PI_HOLE_BIN_DIR are not readonly here because in some functions (checkout),
# they might get set again when the installer is sourced. This causes an
# error due to modifying a readonly variable.
setupVars="/etc/pihole/setupVars.conf"
PI_HOLE_BIN_DIR="/usr/local/bin"
readonly FTL_PID_FILE="/run/pihole-FTL.pid"

readonly colfile="${PI_HOLE_SCRIPT_DIR}/COL_TABLE"
source "${colfile}"

webpageFunc() {
  source "${PI_HOLE_SCRIPT_DIR}/webpage.sh"
  main "$@"
  exit 0
}

listFunc() {
  "${PI_HOLE_SCRIPT_DIR}"/list.sh "$@"
  exit 0
}

debugFunc() {
  local automated
  local web

  # Pull off the `debug` leaving passed call augmentation flags in $1
  shift
  if [[ "$@" == *"-a"* ]]; then
    automated="true"
  fi
  if [[ "$@" == *"-w"* ]]; then
    web="true"
  fi

  AUTOMATED=${automated:-} WEBCALL=${web:-} "${PI_HOLE_SCRIPT_DIR}"/piholeDebug.sh
  exit 0
}

flushFunc() {
  "${PI_HOLE_SCRIPT_DIR}"/piholeLogFlush.sh "$@"
  exit 0
}

arpFunc() {
  "${PI_HOLE_SCRIPT_DIR}"/piholeARPTable.sh "$@"
  exit 0
}

updatePiholeFunc() {
  shift
  "${PI_HOLE_SCRIPT_DIR}"/update.sh "$@"
  exit 0
}

reconfigurePiholeFunc() {
  /etc/.pihole/automated\ install/basic-install.sh --reconfigure
  exit 0;
}

updateGravityFunc() {
  "${PI_HOLE_SCRIPT_DIR}"/gravity.sh "$@"
  exit $?
}

queryFunc() {
  shift
  "${PI_HOLE_SCRIPT_DIR}"/query.sh "$@"
  exit 0
}

chronometerFunc() {
  shift
  "${PI_HOLE_SCRIPT_DIR}"/chronometer.sh "$@"
  exit 0
}


uninstallFunc() {
  "${PI_HOLE_SCRIPT_DIR}"/uninstall.sh
  exit 0
}

versionFunc() {
  shift
  "${PI_HOLE_SCRIPT_DIR}"/version.sh "$@"
  exit 0
}

# Get PID of main pihole-FTL process
getFTLPID() {
  local pid

  if [ -s "${FTL_PID_FILE}" ]; then
    # -s: FILE exists and has a size greater than zero
    pid="$(<"$FTL_PID_FILE")"
    # Exploit prevention: unset the variable if there is malicious content
    # Verify that the value read from the file is numeric
    [[ "$pid" =~ [^[:digit:]] ]] && unset pid
  fi

  # If FTL is not running, or the PID file contains malicious stuff, substitute
  # negative PID to signal this to the caller
  echo "${pid:=-1}"
}

restartDNS() {
  local svcOption svc str output status pid icon
  svcOption="${1:-restart}"

  # Determine if we should reload or restart
  if [[ "${svcOption}" =~ "reload-lists" ]]; then
    # Reloading of the lists has been requested
    # Note 1: This will NOT re-read any *.conf files
    # Note 2: We cannot use killall here as it does
    #         not know about real-time signals
    pid="$(getFTLPID)"
    if [[ "$pid" -eq "-1" ]]; then
      svc="true"
      str="FTL is not running"
      icon="${INFO}"
    else
      svc="kill -RTMIN ${pid}"
      str="Reloading DNS lists"
      icon="${TICK}"
    fi
  elif [[ "${svcOption}" =~ "reload" ]]; then
    # Reloading of the DNS cache has been requested
    # Note: This will NOT re-read any *.conf files
    pid="$(getFTLPID)"
    if [[ "$pid" -eq "-1" ]]; then
      svc="true"
      str="FTL is not running"
      icon="${INFO}"
    else
      svc="kill -HUP ${pid}"
      str="Flushing DNS cache"
      icon="${TICK}"
    fi
  else
    # A full restart has been requested
    svc="service pihole-FTL restart"
    str="Restarting DNS server"
    icon="${TICK}"
  fi

  # Print output to Terminal, but not to Web Admin
  [[ -t 1 ]] && echo -ne "  ${INFO} ${str}..."

  output=$( { ${svc}; } 2>&1 )
  status="$?"

  if [[ "${status}" -eq 0 ]]; then
    [[ -t 1 ]] && echo -e "${OVER}  ${icon} ${str}"
    return 0
  else
    [[ ! -t 1 ]] && local OVER=""
    echo -e "${OVER}  ${CROSS} ${output}"
    return 1
  fi
}

piholeEnable() {
  if [[ "${2}" == "-h" ]] || [[ "${2}" == "--help" ]]; then
    echo "Usage: pihole disable [time]
Example: 'pihole disable', or 'pihole disable 5m'
Disable Pi-hole subsystems

Time:
  #s                  Disable Pi-hole functionality for # second(s)
  #m                  Disable Pi-hole functionality for # minute(s)"
    exit 0

  elif [[ "${1}" == "0" ]]; then
    # Disable Pi-hole
    if grep -cq "BLOCKING_ENABLED=false" "${setupVars}"; then
      echo -e "  ${INFO} Blocking already disabled, nothing to do"
      exit 0
    fi
    if [[ $# > 1 ]]; then
      local error=false
      if [[ "${2}" == *"s" ]]; then
        tt=${2%"s"}
        if [[ "${tt}" =~ ^-?[0-9]+$ ]];then
          local str="Disabling blocking for ${tt} seconds"
          echo -e "  ${INFO} ${str}..."
          local str="Blocking will be re-enabled in ${tt} seconds"
          nohup "${PI_HOLE_SCRIPT_DIR}"/pihole-reenable.sh ${tt} </dev/null &>/dev/null &
        else
          local error=true
        fi
      elif [[ "${2}" == *"m" ]]; then
        tt=${2%"m"}
          if [[ "${tt}" =~ ^-?[0-9]+$ ]];then
          local str="Disabling blocking for ${tt} minutes"
          echo -e "  ${INFO} ${str}..."
          local str="Blocking will be re-enabled in ${tt} minutes"
          tt=$((${tt}*60))
          nohup "${PI_HOLE_SCRIPT_DIR}"/pihole-reenable.sh ${tt} </dev/null &>/dev/null &
        else
          local error=true
        fi
      elif [[ -n "${2}" ]]; then
        local error=true
      else
        echo -e "  ${INFO} Disabling blocking"
      fi

      if [[ ${error} == true ]];then
        echo -e "  ${COL_LIGHT_RED}Unknown format for delayed reactivation of the blocking!${COL_NC}"
        echo -e "  Try 'pihole disable --help' for more information."
        exit 1
      fi

      local str="Pi-hole Disabled"
      sed -i "/BLOCKING_ENABLED=/d" "${setupVars}"
      echo "BLOCKING_ENABLED=false" >> "${setupVars}"
    fi
  else
    # Enable Pi-hole
    killall -q pihole-reenable
    if grep -cq "BLOCKING_ENABLED=true" "${setupVars}"; then
      echo -e "  ${INFO} Blocking already enabled, nothing to do"
      exit 0
    fi
    echo -e "  ${INFO} Enabling blocking"
    local str="Pi-hole Enabled"

    sed -i "/BLOCKING_ENABLED=/d" "${setupVars}"
    echo "BLOCKING_ENABLED=true" >> "${setupVars}"
  fi

  restartDNS reload

  echo -e "${OVER}  ${TICK} ${str}"
}

piholeLogging() {
  shift
  if [[ "${1}" == "-h" ]] || [[ "${1}" == "--help" ]]; then
    echo "Usage: pihole logging [options]
Example: 'pihole logging on'
Specify whether the Pi-hole log should be used

Options:
  on                  Enable the Pi-hole log at /var/log/pihole.log
  off                 Disable and flush the Pi-hole log at /var/log/pihole.log
  off noflush         Disable the Pi-hole log at /var/log/pihole.log"
    exit 0
  elif [[ "${1}" == "off" ]]; then
    # Disable logging
    sed -i 's/^log-queries/#log-queries/' /etc/dnsmasq.d/01-pihole.conf
    sed -i 's/^QUERY_LOGGING=true/QUERY_LOGGING=false/' /etc/pihole/setupVars.conf
    if [[ "${2}" != "noflush" ]]; then
      # Flush logs
      "${PI_HOLE_BIN_DIR}"/pihole -f
    fi
    echo -e "  ${INFO} Disabling logging..."
    local str="Logging has been disabled!"
  elif [[ "${1}" == "on" ]]; then
    # Enable logging
    sed -i 's/^#log-queries/log-queries/' /etc/dnsmasq.d/01-pihole.conf
    sed -i 's/^QUERY_LOGGING=false/QUERY_LOGGING=true/' /etc/pihole/setupVars.conf
    echo -e "  ${INFO} Enabling logging..."
    local str="Logging has been enabled!"
  else
    echo -e "  ${COL_LIGHT_RED}Invalid option${COL_NC}
  Try 'pihole logging --help' for more information."
    exit 1
  fi
  restartDNS
  echo -e "${OVER}  ${TICK} ${str}"
}

analyze_ports() {
  # FTL is listening at least on at least one port when this
  # function is getting called
  echo -e "  ${TICK} DNS service is listening"
  # Check individual address family/protocol combinations
  # For a healthy Pi-hole, they should all be up (nothing printed)
  if grep -q "IPv4.*UDP" <<< "${1}"; then
      echo -e "     ${TICK} UDP (IPv4)"
  else
      echo -e "     ${CROSS} UDP (IPv4)"
  fi
  if grep -q "IPv4.*TCP" <<< "${1}"; then
      echo -e "     ${TICK} TCP (IPv4)"
  else
      echo -e "     ${CROSS} TCP (IPv4)"
  fi
  if grep -q "IPv6.*UDP" <<< "${1}"; then
      echo -e "     ${TICK} UDP (IPv6)"
  else
      echo -e "     ${CROSS} UDP (IPv6)"
  fi
  if grep -q "IPv6.*TCP" <<< "${1}"; then
      echo -e "     ${TICK} TCP (IPv6)"
  else
      echo -e "     ${CROSS} TCP (IPv6)"
  fi
  echo ""
}

statusFunc() {
  # Determine if there is a pihole service is listening on port 53
  local listening
  listening="$(lsof -Pni:53)"
  if grep -q "pihole" <<< "${listening}"; then
    if [[ "${1}" != "web" ]]; then
      analyze_ports "${listening}"
    fi
  else
    case "${1}" in
      "web") echo "-1";;
      *) echo -e "  ${CROSS} DNS service is NOT listening";;
    esac
    return 0
  fi

  # Determine if Pi-hole's blocking is enabled
  if grep -q "BLOCKING_ENABLED=false" /etc/pihole/setupVars.conf; then
    # A config is commented out
    case "${1}" in
      "web") echo 0;;
      *) echo -e "  ${CROSS} Pi-hole blocking is disabled";;
    esac
  elif grep -q "BLOCKING_ENABLED=true" /etc/pihole/setupVars.conf;  then
    # Configs are set
    case "${1}" in
      "web") echo 1;;
      *) echo -e "  ${TICK} Pi-hole blocking is enabled";;
    esac
  else
    # No configs were found
    case "${1}" in
      "web") echo 99;;
      *) echo -e "  ${INFO} Pi-hole blocking will be enabled";;
    esac
    # Enable blocking
    "${PI_HOLE_BIN_DIR}"/pihole enable
  fi
}

tailFunc() {
  # Warn user if Pi-hole's logging is disabled
  local logging_enabled=$(grep -c "^log-queries" /etc/dnsmasq.d/01-pihole.conf)
  if [[ "${logging_enabled}" == "0" ]]; then
    # No "log-queries" lines are found.
    # Commented out lines (such as "#log-queries") are ignored
    echo "  ${CROSS} Warning: Query logging is disabled"
  fi
  echo -e "  ${INFO} Press Ctrl-C to exit"

  # Retrieve IPv4/6 addresses
  source /etc/pihole/setupVars.conf

  # Strip date from each line
  # Color blocklist/blacklist/wildcard entries as red
  # Color A/AAAA/DHCP strings as white
  # Color everything else as gray
  tail -f /var/log/pihole.log | grep --line-buffered "${1}" | sed -E \
    -e "s,($(date +'%b %d ')| dnsmasq\[[0-9]*\]),,g" \
    -e "s,(.*(blacklisted |gravity blocked ).* is (0.0.0.0|::|NXDOMAIN|${IPV4_ADDRESS%/*}|${IPV6_ADDRESS:-NULL}).*),${COL_RED}&${COL_NC}," \
    -e "s,.*(query\\[A|DHCP).*,${COL_NC}&${COL_NC}," \
    -e "s,.*,${COL_GRAY}&${COL_NC},"
  exit 0
}

piholeCheckoutFunc() {
  if [[ "$2" == "-h" ]] || [[ "$2" == "--help" ]]; then
    echo "Usage: pihole checkout [repo] [branch]
Example: 'pihole checkout master' or 'pihole checkout core dev'
Switch Pi-hole subsystems to a different GitHub branch

Repositories:
  core [branch]       Change the branch of Pi-hole's core subsystem
  web [branch]        Change the branch of Web Interface subsystem
  ftl [branch]        Change the branch of Pi-hole's FTL subsystem

Branches:
  master              Update subsystems to the latest stable release
  dev                 Update subsystems to the latest development release
  branchname          Update subsystems to the specified branchname"
    exit 0
  fi

  source "${PI_HOLE_SCRIPT_DIR}"/piholeCheckout.sh
  shift
  checkout "$@"
}

tricorderFunc() {
  if [[ ! -p "/dev/stdin" ]]; then
    echo -e "  ${INFO} Please do not call Tricorder directly"
    exit 1
  fi

  if ! (echo > /dev/tcp/tricorder.pi-hole.net/9998) >/dev/null 2>&1; then
    echo -e "  ${CROSS} Unable to connect to Pi-hole's Tricorder server"
    exit 1
  fi

  if command -v openssl &> /dev/null; then
    openssl s_client -quiet -connect tricorder.pi-hole.net:9998 2> /dev/null < /dev/stdin
    exit "$?"
  else
    echo -e "  ${INFO} ${COL_YELLOW}Security Notice${COL_NC}: ${COL_WHITE}openssl${COL_NC} is not installed
       Your debug log will be transmitted unencrypted via plain-text
       There is a possibility that this could be intercepted by a third party
       If you wish to cancel, press Ctrl-C to exit within 10 seconds"
    secs="10"
    while [[ "$secs" -gt "0" ]]; do
       echo -ne "."
       sleep 1
       : $((secs--))
    done
    echo " "
    nc tricorder.pi-hole.net 9999 < /dev/stdin
    exit "$?"
  fi
}

updateCheckFunc() {
  "${PI_HOLE_SCRIPT_DIR}"/updatecheck.sh "$@"
  exit 0
}

helpFunc() {
  echo "Usage: pihole [options]
Example: 'pihole -w -h'
Add '-h' after specific commands for more information on usage

Whitelist/Blacklist Options:
  -w, whitelist       Whitelist domain(s)
  -b, blacklist       Blacklist domain(s)
  --regex, regex      Regex blacklist domains(s)
  --white-regex       Regex whitelist domains(s)
  --wild, wildcard    Wildcard blacklist domain(s)
  --white-wild        Wildcard whitelist domain(s)
                        Add '-h' for more info on whitelist/blacklist usage

Debugging Options:
  -d, debug           Start a debugging session
                        Add '-a' to automatically upload the log to tricorder.pi-hole.net
  -f, flush           Flush the Pi-hole log
  -r, reconfigure     Reconfigure or Repair Pi-hole subsystems
  -t, tail [arg]      View the live output of the Pi-hole log.
                      Add an optional argument to filter the log
                      (regular expressions are supported)


Options:
  -a, admin           Web interface options
                        Add '-h' for more info on Web Interface usage
  -c, chronometer     Calculates stats and displays to an LCD
                        Add '-h' for more info on chronometer usage
  -g, updateGravity   Update the list of ad-serving domains
  -h, --help, help    Show this help dialog
  -l, logging         Specify whether the Pi-hole log should be used
                        Add '-h' for more info on logging usage
  -q, query           Query the adlists for a specified domain
                        Add '-h' for more info on query usage
  -up, updatePihole   Update Pi-hole subsystems
                        Add '--check-only' to exit script before update is performed.
  -v, version         Show installed versions of Pi-hole, Web Interface & FTL
                        Add '-h' for more info on version usage
  uninstall           Uninstall Pi-hole from your system
  status              Display the running status of Pi-hole subsystems
  enable              Enable Pi-hole subsystems
  disable             Disable Pi-hole subsystems
                        Add '-h' for more info on disable usage
  restartdns          Full restart Pi-hole subsystems
                        Add 'reload' to update the lists and flush the cache without restarting the DNS server
                        Add 'reload-lists' to only update the lists WITHOUT flushing the cache or restarting the DNS server
  checkout            Switch Pi-hole subsystems to a different GitHub branch
                        Add '-h' for more info on checkout usage
  arpflush            Flush information stored in Pi-hole's network tables";
  exit 0
}

if [[ $# = 0 ]]; then
  helpFunc
fi

case "${1}" in
  "-h" | "help" | "--help"      ) helpFunc;;
esac

# Must be root to use this tool
if [[ ! $EUID -eq 0 ]];then
  if [[ -x "$(command -v sudo)" ]]; then
    exec sudo bash "$0" "$@"
    exit $?
  else
    echo -e "  ${CROSS} sudo is needed to run pihole commands.  Please run this script as root or install sudo."
    exit 1
  fi
fi

# Handle redirecting to specific functions based on arguments
case "${1}" in
  "-w" | "whitelist"            ) listFunc "$@";;
  "-b" | "blacklist"            ) listFunc "$@";;
  "--wild" | "wildcard"         ) listFunc "$@";;
  "--regex" | "regex"           ) listFunc "$@";;
  "--white-regex" | "white-regex" ) listFunc "$@";;
  "--white-wild" | "white-wild"   ) listFunc "$@";;
  "-d" | "debug"                ) debugFunc "$@";;
  "-f" | "flush"                ) flushFunc "$@";;
  "-up" | "updatePihole"        ) updatePiholeFunc "$@";;
  "-r"  | "reconfigure"         ) reconfigurePiholeFunc;;
  "-g" | "updateGravity"        ) updateGravityFunc "$@";;
  "-c" | "chronometer"          ) chronometerFunc "$@";;
  "-h" | "help"                 ) helpFunc;;
  "-v" | "version"              ) versionFunc "$@";;
  "-q" | "query"                ) queryFunc "$@";;
  "-l" | "logging"              ) piholeLogging "$@";;
  "uninstall"                   ) uninstallFunc;;
  "enable"                      ) piholeEnable 1;;
  "disable"                     ) piholeEnable 0 "$2";;
  "status"                      ) statusFunc "$2";;
  "restartdns"                  ) restartDNS "$2";;
  "-a" | "admin"                ) webpageFunc "$@";;
  "-t" | "tail"                 ) tailFunc "$2";;
  "checkout"                    ) piholeCheckoutFunc "$@";;
  "tricorder"                   ) tricorderFunc;;
  "updatechecker"               ) updateCheckFunc "$@";;
  "arpflush"                    ) arpFunc "$@";;
  *                             ) helpFunc;;
esac