Issue #382: Validate delta timeout variables

Also take validation functions into a module, and use that in all cases where
we need to check for an integer or string.

Signed-off-by: Pablo Carranza Velez <pablo@resin.io>

src/application.coffee

@@ -15,6 +15,7 @@ TypedError = require 'typed-error'
 fs = Promise.promisifyAll(require('fs'))
 JSONStream = require 'JSONStream'
 proxyvisor = require './proxyvisor'
+{ checkInt } = require './lib/validation'
 
 class UpdatesLockedError extends TypedError
 ImageNotFoundError = (err) ->
@@ -196,8 +197,8 @@ fetch = (app, setDeviceUpdateState = true) ->
 
 			if conf['RESIN_SUPERVISOR_DELTA'] == '1'
 				logSystemEvent(logTypes.downloadAppDelta, app)
-				requestTimeout = conf['RESIN_SUPERVISOR_DELTA_REQUEST_TIMEOUT'] ? 30 * 60 * 1000
+				requestTimeout = checkInt(conf['RESIN_SUPERVISOR_DELTA_REQUEST_TIMEOUT'], positive: true) ? 30 * 60 * 1000
-				totalTimeout = conf['RESIN_SUPERVISOR_DELTA_TOTAL_TIMEOUT'] ? 24 * 60 * 60 * 1000
+				totalTimeout = checkInt(conf['RESIN_SUPERVISOR_DELTA_TOTAL_TIMEOUT'], positive: true) ? 24 * 60 * 60 * 1000
 				dockerUtils.rsyncImageWithProgress(app.imageId, { requestTimeout, totalTimeout }, onProgress)
 			else
 				logSystemEvent(logTypes.downloadApp, app)
@@ -395,7 +396,7 @@ application.poll = ->
 
 # Callback function to set the API poll interval dynamically.
 apiPollInterval = (val) ->
-	config.appUpdatePollInterval = config.checkInt(val) ? 60000
+	config.appUpdatePollInterval = checkInt(val, positive: true) ? 60000
 	console.log('New API poll interval: ' + val)
 	clearInterval(updateStatus.intervalHandle)
 	application.poll()
@@ -443,8 +444,7 @@ wrapAsError = (err) ->
 waitToKill = (app, timeout) ->
 	startTime = Date.now()
 	pollInterval = 100
-	timeout = parseInt(timeout)
+	timeout = checkInt(timeout, positive: true) ? 60000
-	timeout = 60000 if isNaN(timeout)
 	checkFileOrTimeout = ->
 		fs.statAsync(killmePath(app))
 		.catch (err) ->

src/config.coffee

@@ -1,26 +1,12 @@
-checkInt = (s) ->
+{ checkInt, checkString } = require './lib/validation'
-	# Make sure `s` exists and is not an empty string.
-	if !s
-		return
-	i = parseInt(s, 10)
-	if isNaN(i)
-		return
-	return i
-
-checkString = (s) ->
-	# Make sure `s` exists and is not an empty string, or 'null' or 'undefined'.
-	# This might happen if the parsing of config.json on the host using jq is wrong (it is buggy in some versions).
-	if !s? or s == 'null' or s == 'undefined' or s == ''
-		return
-	return s
 
 dockerRoot = checkString(process.env.DOCKER_ROOT) ? '/mnt/root/var/lib/rce'
 
 # Defaults needed for both gosuper and node supervisor are declared in entry.sh
 module.exports =
 	apiEndpoint: checkString(process.env.API_ENDPOINT) ? 'https://api.resin.io'
-	apiTimeout: checkInt(process.env.API_TIMEOUT) ? 15 * 60 * 1000
+	apiTimeout: checkInt(process.env.API_TIMEOUT, positive: true) ? 15 * 60 * 1000
-	listenPort: checkInt(process.env.LISTEN_PORT) ? 80
+	listenPort: checkInt(process.env.LISTEN_PORT, positive: true) ? 80
 	gosuperAddress: "http://unix:#{process.env.GOSUPER_SOCKET}:"
 	deltaHost: checkString(process.env.DELTA_ENDPOINT) ? 'https://delta.resin.io'
 	registryEndpoint: checkString(process.env.REGISTRY_ENDPOINT) ? 'registry.resin.io'
@@ -32,15 +18,14 @@ module.exports =
 	supervisorImage: checkString(process.env.SUPERVISOR_IMAGE) ? 'resin/rpi-supervisor'
 	configMountPoint: checkString(process.env.CONFIG_MOUNT_POINT) ? '/mnt/mmcblk0p1/config.json'
 	ledFile: checkString(process.env.LED_FILE) ? '/sys/class/leds/led0/brightness'
-	bootstrapRetryDelay: checkInt(process.env.BOOTSTRAP_RETRY_DELAY_MS) ? 30000
+	bootstrapRetryDelay: checkInt(process.env.BOOTSTRAP_RETRY_DELAY_MS, positive: true) ? 30000
-	restartSuccessTimeout: checkInt(process.env.RESTART_SUCCESS_TIMEOUT) ? 60000
+	restartSuccessTimeout: checkInt(process.env.RESTART_SUCCESS_TIMEOUT, positive: true) ? 60000
-	appUpdatePollInterval: checkInt(process.env.APPLICATION_UPDATE_POLL_INTERVAL) ? 60000
+	appUpdatePollInterval: checkInt(process.env.APPLICATION_UPDATE_POLL_INTERVAL, positive: true) ? 60000
 	successMessage: 'SUPERVISOR OK'
 	forceSecret:
 		api: checkString(process.env.RESIN_SUPERVISOR_SECRET) ? null
 		logsChannel: checkString(process.env.RESIN_SUPERVISOR_LOGS_CHANNEL) ? null
 	vpnStatusPath: checkString(process.env.VPN_STATUS_PATH) ? '/mnt/root/run/openvpn/vpn_status'
-	checkInt: checkInt
 	hostOsVersionPath: checkString(process.env.HOST_OS_VERSION_PATH) ? '/mnt/root/etc/os-release'
 	dockerRoot: dockerRoot
 	btrfsRoot: checkString(process.env.BTRFS_ROOT) ? "#{dockerRoot}/btrfs/subvolumes"

src/lib/validation.coffee

@@ -0,0 +1,17 @@
+exports.checkInt = (s, options = {}) ->
+	# Make sure `s` exists and is not an empty string.
+	if !s
+		return
+	i = parseInt(s, 10)
+	if isNaN(i)
+		return
+	if options.positive && i <= 0
+		return
+	return i
+
+exports.checkString = (s) ->
+	# Make sure `s` exists and is not an empty string, or 'null' or 'undefined'.
+	# This might happen if the parsing of config.json on the host using jq is wrong (it is buggy in some versions).
+	if !s? or s == 'null' or s == 'undefined' or s == ''
+		return
+	return s