tools/mgmt/nminstall

#!/bin/bash
#
# Installs node manager on the local machine.
#
# Specifically:
#
# 1. Fetches the binaries required for a node manager installation from a few
# possible sources.
#
# 2. Sets up the helper with setuid.  The helper binary needs to be owned by
# root and have the suid bit set, to enable the node manager to run binaries
# under different system accounts than itself.
#
# 3. Runs the self-install command on the node manager.
#
# Usage:
#
# # Gets binaries from local repository (TODO(caprita): implement)
# ./nminstall <install parent dir>
#
# # Gets binaries from local filesystem
# ./nminstall <install parent dir> /path/to/binaries
#
# # Gets binaries from HTTP server (TODO(caprita): implement)
# ./nminstall <install parent dir> http://host/path

set -e

usage() {
  echo "usage:"
  echo "./nminstall <install parent dir> [<binary source>]"
}

# TODO(caprita): Also agent.
readonly BIN_NAMES=(noded suidhelper)

#######################################################
# Fetches binaries needed by node manager installation.
# Globals:
#   BIN_NAMES
#   VEYRON_ROOT
# Arguments:
#   destination for binaries
#   source of binaries
# Returns:
#   None
#######################################
get_binaries() {
  local -r BIN_INSTALL="$1"
  local -r BIN_SOURCE="$2"

  local bin_names_str=""
  for bin_name in ${BIN_NAMES[@]}; do
    bin_names_str+=" ${bin_name}"
  done
  # If source is not specified, try to look for it in the repository.
  if [[ -z "${BIN_SOURCE}" ]]; then
    if [[ -z "${VEYRON_ROOT}" ]]; then
      echo 'ERROR: binary source not specified and no local repository available'
      exit 1
    fi
    local -r REPO_BIN_DIR="${VEYRON_ROOT}/veyron/go/bin"
    echo "Fetching binaries:${bin_names_str} from: ${REPO_BIN_DIR} ..."
    for bin_name in ${BIN_NAMES[@]}; do
      local repo_source="${REPO_BIN_DIR}/${bin_name}"
      if [[ -x "${repo_source}" ]]; then
        local file_destination="${BIN_INSTALL}/${bin_name}"
	cp "${repo_source}" "${file_destination}"
        chmod 700 "${file_destination}"
      else
	echo "couldn't find ${repo_source}"
	exit 1
      fi
    done
    echo "Binaries are in ${BIN_INSTALL}."
    return
  fi

  echo 'ERROR: couldn'"'"'t fetch binaries.'
  exit 1
}

main() {
  local -r INSTALL_PARENT_DIR="$1"
  if [[ -z "${INSTALL_PARENT_DIR}" ]]; then
    echo 'No local install destination specified!'
    usage
    exit 1
  fi

  if [[ ! -d "${INSTALL_PARENT_DIR}" ]]; then
    echo "${INSTALL_PARENT_DIR} is not a directory!"
    exit 1
  fi

  local -r INSTALL_DIR="${INSTALL_PARENT_DIR}/node_manager"

  # TODO(caprita): Check that the node manager is not already installed before
  # proceeding.  We should require an explicit uninstall to avoid wiping away
  # the node manager accidentally.
  sudo rm -rf "${INSTALL_DIR}"
  mkdir -m 700 "${INSTALL_DIR}"

  local -r BIN_INSTALL="${INSTALL_DIR}/bin"
  mkdir -m 700 "${BIN_INSTALL}"

  # Fetch the binaries.
  local -r BIN_SOURCE="$2"
  get_binaries "${BIN_INSTALL}" "${BIN_SOURCE}"

  # Set up the suidhelper.
  echo "Configuring suidhelper ..."
  local -r SETUID_SCRIPT="${BIN_INSTALL}/suidhelper"
  sudo bash -c "chown root:root \"${SETUID_SCRIPT}\"; chmod 4551 \"${SETUID_SCRIPT}\""
  echo "Suidhelper configured."

  # Tell the node manager to install itself.
  local -r NM_ROOT="${INSTALL_DIR}/nmroot"
  echo "Installing node manager under ${NM_ROOT} ..."
  VEYRON_NM_CURRENT="${INSTALL_DIR}/curr" VEYRON_NM_ROOT="${NM_ROOT}" VEYRON_NM_HELPER="${SETUID_SCRIPT}" "${BIN_INSTALL}/noded" --install_self
  echo "Node manager installed."
}

main "$@"