diff --git a/src/main/java/ctbrec/recorder/server/AbstractCtbrecServlet.java b/src/main/java/ctbrec/recorder/server/AbstractCtbrecServlet.java
new file mode 100644
index 00000000..1c0085b6
--- /dev/null
+++ b/src/main/java/ctbrec/recorder/server/AbstractCtbrecServlet.java
@@ -0,0 +1,47 @@
+package ctbrec.recorder.server;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+
+import ctbrec.Config;
+import ctbrec.Hmac;
+
+public abstract class AbstractCtbrecServlet extends HttpServlet {
+
+    boolean checkAuthentication(HttpServletRequest req, String body) throws IOException, InvalidKeyException, NoSuchAlgorithmException, IllegalStateException {
+        boolean authenticated = false;
+        if(Config.getInstance().getSettings().key != null) {
+            String reqParamHmac = req.getParameter("hmac");
+            String httpHeaderHmac = req.getHeader("CTBREC-HMAC");
+            String hmac = null;
+            if(reqParamHmac != null) {
+                hmac = reqParamHmac;
+            }
+            if(httpHeaderHmac != null) {
+                hmac = httpHeaderHmac;
+            }
+
+            byte[] key = Config.getInstance().getSettings().key;
+            authenticated = Hmac.validate(body, key, hmac);
+        } else {
+            authenticated = true;
+        }
+        return authenticated;
+    }
+
+
+    String body(HttpServletRequest req) throws IOException {
+        StringBuilder body = new StringBuilder();
+        BufferedReader br = req.getReader();
+        String line= null;
+        while( (line = br.readLine()) != null ) {
+            body.append(line).append("\n");
+        }
+        return body.toString().trim();
+    }
+}
diff --git a/src/main/java/ctbrec/recorder/server/HlsServlet.java b/src/main/java/ctbrec/recorder/server/HlsServlet.java
index 88631098..a36239ec 100644
--- a/src/main/java/ctbrec/recorder/server/HlsServlet.java
+++ b/src/main/java/ctbrec/recorder/server/HlsServlet.java
@@ -6,7 +6,6 @@ import java.io.FileNotFoundException;
 import java.io.IOException;
 
 import javax.servlet.ServletException;
-import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
@@ -18,7 +17,7 @@ import com.iheartradio.m3u8.PlaylistException;
 
 import ctbrec.Config;
 
-public class HlsServlet extends HttpServlet {
+public class HlsServlet extends AbstractCtbrecServlet {
 
     private static final transient Logger LOG = LoggerFactory.getLogger(HlsServlet.class);
 
@@ -34,8 +33,24 @@ public class HlsServlet extends HttpServlet {
         File recordingsDir = new File(config.getSettings().recordingsDir);
         File requestedFile = new File(recordingsDir, request);
 
+        //        try {
+        //            boolean isRequestAuthenticated = checkAuthentication(req, req.getRequestURI());
+        //            if (!isRequestAuthenticated) {
+        //                resp.setStatus(SC_UNAUTHORIZED);
+        //                String response = "{\"status\": \"error\", \"msg\": \"HMAC does not match\"}";
+        //                resp.getWriter().write(response);
+        //                return;
+        //            }
+        //        } catch (InvalidKeyException | NoSuchAlgorithmException | IllegalStateException e1) {
+        //            resp.setStatus(SC_UNAUTHORIZED);
+        //            String response = "{\"status\": \"error\", \"msg\": \"Authentication failed\"}";
+        //            resp.getWriter().write(response);
+        //            return;
+        //        }
+
         if (requestedFile.getCanonicalPath().startsWith(config.getSettings().recordingsDir)) {
             if (requestedFile.getName().equals("playlist.m3u8")) {
+
                 try {
                     servePlaylist(req, resp, requestedFile);
                 } catch (ParseException | PlaylistException e) {
diff --git a/src/main/java/ctbrec/recorder/server/HttpServer.java b/src/main/java/ctbrec/recorder/server/HttpServer.java
index 9faaf749..8632e865 100644
--- a/src/main/java/ctbrec/recorder/server/HttpServer.java
+++ b/src/main/java/ctbrec/recorder/server/HttpServer.java
@@ -1,6 +1,7 @@
 package ctbrec.recorder.server;
 
 import java.io.IOException;
+import java.net.BindException;
 
 import org.eclipse.jetty.server.Handler;
 import org.eclipse.jetty.server.HttpConfiguration;
@@ -82,8 +83,13 @@ public class HttpServer {
         holder = new ServletHolder(hlsServlet);
         handler.addServletWithMapping(holder, "/hls/*");
 
-        server.start();
-        server.join();
+        try {
+            server.start();
+            server.join();
+        } catch (BindException e) {
+            LOG.error("Port {} is already in use", http.getPort(), e);
+            System.exit(1);
+        }
     }
 
     public static void main(String[] args) throws Exception {
diff --git a/src/main/java/ctbrec/recorder/server/RecorderServlet.java b/src/main/java/ctbrec/recorder/server/RecorderServlet.java
index a660b7b1..976c5b68 100644
--- a/src/main/java/ctbrec/recorder/server/RecorderServlet.java
+++ b/src/main/java/ctbrec/recorder/server/RecorderServlet.java
@@ -5,16 +5,12 @@ import static javax.servlet.http.HttpServletResponse.SC_INTERNAL_SERVER_ERROR;
 import static javax.servlet.http.HttpServletResponse.SC_OK;
 import static javax.servlet.http.HttpServletResponse.SC_UNAUTHORIZED;
 
-import java.io.BufferedReader;
 import java.io.IOException;
-import java.security.InvalidKeyException;
-import java.security.NoSuchAlgorithmException;
 import java.time.Instant;
 import java.util.Iterator;
 import java.util.List;
 
 import javax.servlet.ServletException;
-import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
@@ -24,14 +20,12 @@ import org.slf4j.LoggerFactory;
 import com.squareup.moshi.JsonAdapter;
 import com.squareup.moshi.Moshi;
 
-import ctbrec.Config;
-import ctbrec.Hmac;
 import ctbrec.InstantJsonAdapter;
 import ctbrec.Model;
 import ctbrec.Recording;
 import ctbrec.recorder.Recorder;
 
-public class RecorderServlet extends HttpServlet {
+public class RecorderServlet extends AbstractCtbrecServlet {
 
     private static final transient Logger LOG = LoggerFactory.getLogger(RecorderServlet.class);
 
@@ -129,31 +123,6 @@ public class RecorderServlet extends HttpServlet {
         }
     }
 
-    private boolean checkAuthentication(HttpServletRequest req, String body) throws IOException, InvalidKeyException, NoSuchAlgorithmException, IllegalStateException {
-        boolean authenticated = false;
-        if(Config.getInstance().getSettings().key != null) {
-            if(req.getHeader("CTBREC-HMAC") == null) {
-                authenticated = false;
-            }
-
-            byte[] key = Config.getInstance().getSettings().key;
-            authenticated = Hmac.validate(body, key, req.getHeader("CTBREC-HMAC"));
-        } else {
-            authenticated = true;
-        }
-        return authenticated;
-    }
-
-    private String body(HttpServletRequest req) throws IOException {
-        StringBuilder body = new StringBuilder();
-        BufferedReader br = req.getReader();
-        String line= null;
-        while( (line = br.readLine()) != null ) {
-            body.append(line).append("\n");
-        }
-        return body.toString().trim();
-    }
-
     private static class Request {
         public String action;
         public Model model;