feature: allow third party apps to integrate with security

Specifically done to enable security for node

lib/tokensecurity.js

@@ -226,6 +226,23 @@ module.exports = function (app, config) {
     app.put('/signalk/v1/*', writeAuthenticationMiddleware(false))
   }
 
+  strategy.validateLogin = function (userName, password, cb) {
+    var configuration = getConfiguration()
+    var user = configuration.users.find(user => user.username == userName)
+    if (!user) {
+      cb(false)
+    }
+    bcrypt.compare(password, user.password, (err, matches) => {
+      cb(matches)
+    })
+  }
+
+  strategy.getUserType = function (userName) {
+    var configuration = getConfiguration()
+    var user = configuration.users.find(user => user.username == userName)
+    return user ? user.type : null
+  }
+
   strategy.generateToken = function (req, res, next, id, expiration) {
     var configuration = getConfiguration()
     var payload = { id: id }
@@ -235,6 +252,11 @@ module.exports = function (app, config) {
     res.send(token)
   }
 
+  strategy.allowReadOnly = function () {
+    var configuration = getConfiguration()
+    return configuration.allow_readonly
+  }
+
   strategy.allowRestart = function (req) {
     return req.isAuthenticated && req.user.type == 'admin'
   }