commands

#!/usr/bin/env bash
set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x

APP=$2
SHARED_KEY_TO_ADD=$2
SHARED_KEY_TO_ADD_APP=$3
HOSTNAME_TO_ADD=$2
HOSTNAME_TO_ADD_APP=$3
HOSTNAME_TO_REMOVE=$2
HOSTNAME_TO_REMOVE_APP=$3

APP_SPECIFIC_HOSTKEYS_FOLDER="$DOKKU_ROOT/.hostkeys/$APP/.ssh"
APP_SPECIFIC_HOSTKEYS_FILE="$APP_SPECIFIC_HOSTKEYS_FOLDER/known_hosts"
SHARED_HOSTKEYS_FOLDER="$DOKKU_ROOT/.hostkeys/shared/.ssh"
SHARED_HOSTKEYS_FILE="$SHARED_HOSTKEYS_FOLDER/known_hosts"

check_exists() {
  if [[ ! -d "$DOKKU_ROOT/$APP" ]]; then
    echo "App must exist before managing hostkeys for it"
    exit 1
  fi
}

check_app() {
  if [[ -z "$APP" ]]; then
    echo "You must specify an app name"
    exit 1
  fi
}

check_install() {
  if [[ ! -d "$SHARED_HOSTKEYS_FOLDER" ]]; then
    echo "No shared keys folder available. Did you run 'dokku plugins-install'? Exiting."
    exit 1
  fi

  if [[ ! -f "$SHARED_HOSTKEYS_FILE" ]]; then
    echo "No shared keys file available. Did you run 'dokku plugins-install'? Exiting."
    exit 1
  fi
}

check_install_app() {
  if [[ ! -d "$APP_SPECIFIC_HOSTKEYS_FOLDER" ]]; then
    echo "No app specific keys folder available. creating.."
    mkdir -p "$APP_SPECIFIC_HOSTKEYS_FOLDER"
    chmod 700 "$APP_SPECIFIC_HOSTKEYS_FOLDER"
    chown -R dokku:dokku "$DOKKU_ROOT/.hostkeys/$APP"
  fi

  if [[ ! -f "$APP_SPECIFIC_HOSTKEYS_FILE" ]]; then
    echo "No app specific keys file available. creating.."
    touch "$APP_SPECIFIC_HOSTKEYS_FILE"
    chmod 644 "$APP_SPECIFIC_HOSTKEYS_FILE"
    chown -R dokku:dokku "$DOKKU_ROOT/.hostkeys/$APP"
  fi
}

print_explanation() {
  cat<<EOF
    The hostkeys plugin manages the known_hosts file for your apps.

    You need those known_hosts files, when you want to open a SSH connection to a foreign host,
    such as when compiling the app and pulling in dependencies.

    After adding hostkeys to your Dokku host/app, they will automatically be baked in on the
    next time you compile your app.

    There are 2 types of keys:
    1.) Shared Keys
    Shared keys are valid for all your apps on the Dokku host. You may probably want to add
    some popular hosts in there such as BitBucket, GitHub or even your private VCS that is reachable.

    2.) App-Level Hostkeys
    App-Level Hostkeys may be needed for external dependencies which you licensed, or that reside
    on a different host

    Auto-Adding Hostkeys
    --------------------
    There is another possibility to add host keys, if you do not want to enter a hostkey manually:
    You can autoadd hosts. You provide the hostname and your Dokku host will resolve it for you.
    (THIS IS NOT A GOOD PRACTICE!)
    You should only do this if you are 100% sure your DNS is not compromised.

    $ dokku hostkeys:shared:autoadd github.com
    This command would automatically discover the hostkeys for github.com, add it to the shared
    known_hosts file and add it to your apps slug on recompile.

    $ dokku hostkeys:shared:autoadd mycoolapp github.com
    This command would automatically discover the hostkeys for github.com, add it to your known_hosts
    file for the mycoolapp app and will be compiled inside the slug on recompile.

    You may as well want to have a look at the dokku-deployment-keys plugin on GitHub:
    http://github.com/cedricziel/dokku-deployment-keys

    Projects are kept separate because they each do one different thing.

    Available Commands:
    -------------------
EOF
}

print_help() {
  cat<<EOF
    hostkeys, Print an explanation (Useful to get the concept)
    hostkeys:shared:show, Show shared hostkeys
    hostkeys:shared:add, Add a shared hostkey
    hostkeys:shared:delete, Deletes all shared hostkeys
    hostkeys:shared:delete <hostname>, Deletes the shared hostkeys for the given host
    hostkeys:shared:autoadd <hostname>, Automatically add hostkeys for a given host to the shared hostkeys
    hostkeys:app:show <app>, Show all hostkeys for a given app
    hostkeys:app:add <app>, Add a app-specific hostkey
    hostkeys:app:delete <app>, Deletes all app-specific hostkeys
    hostkeys:app:autoadd <app> <hostname>, Automatically add hostkeys for a given host to the shared hostkeys
EOF
  return
}

print_shared_keys() {
  check_install
  cat<<EOF
The following SHARED hostkeys have been registered:
---------------------------------------------------
EOF
  if [[ ! -s "$SHARED_HOSTKEYS_FILE" ]]; then
    echo "No keys registered. Use dokku 'hostkeys:shared:add <key>' to add one."
  else
    cat "$SHARED_HOSTKEYS_FILE"
  fi
}

add_shared_key() {
  check_install
  if [[ ! -n "$2" ]]; then
    echo $SHARED_KEY_TO_ADD >> "$SHARED_HOSTKEYS_FILE"
    echo "Added $SHARED_KEY_TO_ADD to the list of shared hostkeys"
  else
    echo "Empty argument. Try again."
  fi
}

delete_shared_keys() {
  check_install
  if [[ ! -n "$2" ]]; then
    ssh-keygen -f "$SHARED_HOSTKEYS_FILE" -R "$HOSTNAME_TO_REMOVE"
    rm "$SHARED_HOSTKEYS_FOLDER/known_hosts.old"
    echo "Deleted hostkey for $HOSTNAME_TO_REMOVE as well as the backup."
  else
    > $SHARED_HOSTKEYS_FILE
    echo "Emptied the shared hostkey file. All apps will loose the shared keys on next push. Make sure you add the required ones"
  fi
}

autoadd_shared_key() {
  check_install
  if [[ -n "$HOSTNAME_TO_ADD" ]]; then
    ssh-keyscan -H "$HOSTNAME_TO_ADD" >> "$SHARED_HOSTKEYS_FILE"
    echo "Added keys for $HOSTNAME_TO_ADD"
  else
    echo "Please enter the name of the host as argument"
  fi
}

add_app_key() {
  check_app
  check_exists
  check_install_app
  if [[ ! -n "$3" ]]; then
    echo $SHARED_KEY_TO_ADD_APP >> "$APP_SPECIFIC_HOSTKEYS_FILE"
    echo "Added $SHARED_KEY_TO_ADD_APP to the list of shared hostkeys"
  else
    echo "Empty argument. Try again."
  fi
}

autoadd_app_key(){
  check_app
  check_exists
  check_install_app
  if [[ -n "$HOSTNAME_TO_ADD_APP" ]]; then
    ssh-keyscan -H "$HOSTNAME_TO_ADD_APP" >> "$APP_SPECIFIC_HOSTKEYS_FILE"
    echo "Added keys for $HOSTNAME_TO_ADD_APP"
  else
    echo "Please enter the name of the host as argument"
  fi
}

delete_app_keys() {
  check_app
  check_exists
  check_install_app
  if [[ -n "$3" ]]; then
    ssh-keygen -f "$APP_SPECIFIC_HOSTKEYS_FILE" -R "$HOSTNAME_TO_REMOVE_APP"
    rm "$APP_SPECIFIC_HOSTKEYS_FOLDER/known_hosts.old"
    echo "Deleted hostkey for $HOSTNAME_TO_REMOVE as well as the backup."
  else
    > $APP_SPECIFIC_HOSTKEYS_FILE
    echo "Emptied the app specific hostkey file. Your app looses the specific keys on the next push. Make sure you add the required ones"
  fi
}

print_keys_for_app() {
  check_app
  check_exists
  check_install_app
  print_shared_keys
  cat<<EOF

The following APP SPECIFIC hostkeys have been registered:
---------------------------------------------------------
EOF
  if [[ ! -s "$APP_SPECIFIC_HOSTKEYS_FILE" ]]; then
    echo "No keys registered. Use dokku 'hostkeys:app:add <key>' to add one."
  else
    cat "$APP_SPECIFIC_HOSTKEYS_FILE"
  fi
}

case "$1" in
  hostkeys)
    print_explanation
    print_help
    ;;

  hostkeys:shared:show)
    print_shared_keys
    ;;

  hostkeys:shared:add)
    add_shared_key "$@"
    ;;

  hostkeys:shared:delete)
    delete_shared_keys "$@"
    ;;

  hostkeys:shared:autoadd)
    autoadd_shared_key
    ;;

  hostkeys:app:show)
    print_keys_for_app
    ;;

  hostkeys:app:add)
    add_app_key "$@"
    ;;

  hostkeys:app:delete)
    delete_app_keys "$@"
    ;;

  hostkeys:app:autoadd)
    autoadd_app_key
    ;;

  help | hostkeys:help)
    if [[ -n $DOKKU_API_VERSION ]]; then
      print_help
    else
      cat && print_help
    fi
    ;;

  *)
    exit $DOKKU_NOT_IMPLEMENTED_EXIT
    ;;
esac