Implemented scan auth middleware

ref #67

src/middlewares/ScanAuth.ts

@@ -0,0 +1,68 @@
+import * as argon2 from "argon2";
+import { Request, Response } from 'express';
+import { getConnectionManager } from 'typeorm';
+import { ScanStation } from '../models/entities/ScanStation';
+import authchecker from './authchecker';
+
+/**
+ * This middleware handels the authentification of scan station api tokens.
+ * The tokens have to be provided via Bearer auth header.
+ * @param req Express request object.
+ * @param res Express response object.
+ * @param next Next function to call on success.
+ */
+const ScanAuth = async (req: Request, res: Response, next: () => void) => {
+    let provided_token: string = req.headers["authorization"];
+    if (provided_token == "" || provided_token === undefined || provided_token === null) {
+        res.status(401).send("No api token provided.");
+        return;
+    }
+
+    try {
+        provided_token = provided_token.replace("Bearer ", "");
+    } catch (error) {
+        res.status(401).send("No valid jwt or api token provided.");
+        return;
+    }
+
+    let prefix = "";
+    try {
+        prefix = provided_token.split(".")[0];
+    }
+    finally {
+        if (prefix == "" || prefix == undefined || prefix == null) {
+            res.status(401).send("Api token non-existant or invalid syntax.");
+            return;
+        }
+    }
+
+    const station = await getConnectionManager().get().getRepository(ScanStation).findOne({ prefix: prefix });
+    if (!station) {
+        let user_authorized = false;
+        try {
+            let action = { request: req, response: res, context: null, next: next }
+            user_authorized = await authchecker(action, ["SCAN:CREATE"]);
+        }
+        finally {
+            if (user_authorized == false) {
+                res.status(401).send("Api token non-existant or invalid syntax.");
+                return;
+            }
+            else {
+                next();
+            }
+        }
+    }
+    else {
+        if (station.enabled == false) {
+            res.status(401).send("Station disabled.");
+        }
+        if (!(await argon2.verify(station.key, provided_token))) {
+            res.status(401).send("Api token invalid.");
+            return;
+        }
+
+        next();
+    }
+}
+export default ScanAuth;