improving path handling, working on authorization flow

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

de.srsoftware.oidc.api/src/main/java/de/srsoftware/oidc/api/PathHandler.java

@@ -1,6 +1,7 @@
 /* © SRSoftware 2024 */
 package de.srsoftware.oidc.api;
 
+import static java.net.HttpURLConnection.HTTP_OK;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.sun.net.httpserver.HttpExchange;
@@ -15,30 +16,58 @@ import org.json.JSONObject;
 
 public abstract class PathHandler implements HttpHandler {
 	public static final String CONTENT_TYPE = "Content-Type";
+	public static final String GET	        = "GET";
 	public static final String JSON	        = "application/json";
 	public static final String POST	        = "POST";
 
-	private String path;
+	private String[] paths;
 
 	public class Bond {
-		Bond(String p) {
-			path = p;
+		Bond(String[] paths) {
+			PathHandler.this.paths = paths;
 		}
 		public HttpServer on(HttpServer server) {
-			server.createContext(path, PathHandler.this);
+			for (var path : paths) server.createContext(path, PathHandler.this);
 			return server;
 		}
 	}
 
-	public Bond bindPath(String path) {
+	public Bond bindPath(String... path) {
 		return new Bond(path);
 	}
 
+	public boolean doGet(String path, HttpExchange ex) throws IOException {
+		return false;
+	}
+	public boolean doPost(String path, HttpExchange ex) throws IOException {
+		return false;
+	}
+
+	@Override
+	public void handle(HttpExchange ex) throws IOException {
+		String path   = relativePath(ex);
+		String method = ex.getRequestMethod();
+		System.out.printf("%s %s\n", method, path);
+		boolean dummy = switch (method) {
+			case POST -> doPost(path,ex);
+			case GET -> doGet(path,ex);
+			default -> false;
+		};
+		ex.getResponseBody().close();
+	}
+
 	public String relativePath(HttpExchange ex) {
-		var path = ex.getRequestURI().toString();
-		if (path.startsWith(this.path)) path = path.substring(this.path.length());
-		if (path.startsWith("/")) path = path.substring(1);
-		return path;
+		var requestPath = ex.getRequestURI().toString();
+		for (var path : paths){
+					if (requestPath.startsWith(path)) {
+						requestPath = requestPath.substring(path.length());
+						break;
+					}
+				}
+				if (!requestPath.startsWith("/")) requestPath = "/" + requestPath;
+				var pos = requestPath.indexOf("?");
+				if (pos >= 0) requestPath = requestPath.substring(0, pos);
+				return requestPath;
 		}
 
 		/******* begin of static methods *************/
@@ -55,6 +84,10 @@ public abstract class PathHandler implements HttpHandler {
 			return Optional.ofNullable(ex.getRequestHeaders().get(key)).map(List::stream).map(Stream::findFirst).orElse(Optional.empty());
 		}
 
+		public static boolean isPost(String method) {
+			return POST.equals(method);
+		}
+
 		public static JSONObject json(HttpExchange ex) throws IOException {
 			return new JSONObject(body(ex));
 		}
@@ -63,8 +96,23 @@ public abstract class PathHandler implements HttpHandler {
 			return getHeader(ex, "Accept-Language").map(s -> Arrays.stream(s.split(","))).map(Stream::findFirst).orElse(Optional.empty());
 		}
 
-	public static void sendEmptyResponse(int statusCode, HttpExchange ex) throws IOException {
+
+		public static String prefix(HttpExchange ex) {
+			return "http://%s".formatted(ex.getRequestHeaders().getFirst("Host"));
+		}
+
+		public static boolean sendEmptyResponse(int statusCode, HttpExchange ex) throws IOException {
 			ex.sendResponseHeaders(statusCode, 0);
-		ex.getResponseBody().close();
+			return false;
+		}
+
+		public static boolean sendContent(HttpExchange ex, byte[] bytes) throws IOException {
+			ex.sendResponseHeaders(HTTP_OK, bytes.length);
+			ex.getResponseBody().write(bytes);
+			return true;
+		}
+
+		public static boolean sendContent(HttpExchange ex, Object o) throws IOException {
+			return sendContent(ex, o.toString().getBytes(UTF_8));
 		}
 	}

de.srsoftware.oidc.app/src/main/java/de/srsoftware/oidc/app/Application.java

@@ -18,7 +18,11 @@ import java.util.*;
 import java.util.concurrent.Executors;
 
 public class Application {
+	public static final String  BACKEND         = "/api";
+	private static final String FAVICON         = "/favicon.ico";
+	public static final String  ROOT            = "/";
 	public static final String  STATIC_PATH     = "/web";
+	private static final String WELL_KNOWN      = "/.well-known";
 	public static final String  FIRST_USER      = "admin";
 	public static final String  FIRST_USER_PASS = "admin";
 	public static final String  FIRST_UUID      = UUID.randomUUID().toString();
@@ -36,9 +40,9 @@ public class Application {
 		UserService    userService    = fileStore;
 		SessionService sessionService = fileStore;
 		HttpServer     server         = HttpServer.create(new InetSocketAddress(8080), 0);
-		new StaticPages(basePath).bindPath(STATIC_PATH).on(server);
-		new Forward(INDEX).bindPath("/").on(server);
-		new Backend(sessionService, userService).bindPath("/api").on(server);
+		new StaticPages(basePath).bindPath(STATIC_PATH, FAVICON).on(server);
+		new Forward(INDEX).bindPath(ROOT).on(server);
+		new Backend(sessionService, userService).bindPath(BACKEND, WELL_KNOWN).on(server);
 		server.setExecutor(Executors.newCachedThreadPool());
 		server.start();
 	}

de.srsoftware.oidc.backend/src/main/java/de/srsoftware/oidc/backend/Backend.java

@@ -15,6 +15,8 @@ import java.util.Optional;
 import org.json.JSONObject;
 
 public class Backend extends PathHandler {
+	private static final String CLIENT_ID = "client_id";
+	private static final String REDIRECT_URI = "redirect_uri";
 	private final SessionService sessions;
 	private final UserService    users;
 
@@ -23,57 +25,81 @@ public class Backend extends PathHandler {
 		users    = userService;
 	}
 
-	private void doLogin(HttpExchange ex) throws IOException {
+	private boolean authorize(HttpExchange ex, Session session) throws IOException {
+		var json = json(ex);
+		var clientId = json.getString(CLIENT_ID);
+		var redirect = json.getString(REDIRECT_URI);
+		System.out.println(json);
+		return sendEmptyResponse(HTTP_NOT_FOUND,ex);
+	}
+
+	private boolean doLogin(HttpExchange ex) throws IOException {
 		var body = json(ex);
 
 		var username = body.has(USERNAME) ? body.getString(USERNAME) : null;
 		var password = body.has(PASSWORD) ? body.getString(PASSWORD) : null;
 
 		Optional<User> user = users.load(username, password);
-		if (user.isPresent()) {
-			var session = sessions.createSession(user.get());
-			sendUserAndCookie(ex, session);
-			return;
-		}
-		sendEmptyResponse(HTTP_UNAUTHORIZED, ex);
+		if (user.isPresent()) return sendUserAndCookie(ex, sessions.createSession(user.get()));
+		return sendEmptyResponse(HTTP_UNAUTHORIZED, ex);
 	}
 
 	@Override
-	public void handle(HttpExchange ex) throws IOException {
-		String path   = relativePath(ex);
-		String method = ex.getRequestMethod();
-		System.out.printf("%s %s…", method, path);
-
-		var session = getSession(ex);
-		if ("login".equals(path) && POST.equals(method)) {
-			doLogin(ex);  // TODO: prevent brute force
-			return;
+	public boolean doGet(String path, HttpExchange ex) throws IOException {
+		System.out.printf("GET %s…\n", path);
+		switch (path) {
+			case "/openid-configuration":
+				return openidConfig(ex);
 		}
-		if (session.isEmpty()) {
-			sendEmptyResponse(HTTP_UNAUTHORIZED, ex);
-			System.err.println("unauthorized");
-			return;
+		return sendEmptyResponse(HTTP_NOT_FOUND, ex);
+	}
+
+	@Override
+	public boolean doPost(String path, HttpExchange ex) throws IOException {
+		System.out.printf("POST %s…\n", path);
+
+		// pre-login paths
+		switch (path) {
+			case "/login":
+				return doLogin(ex);
 		}
+		var optSession = getSession(ex);
+		if (optSession.isEmpty()) return sendEmptyResponse(HTTP_UNAUTHORIZED, ex);
+
+		// post-login paths
+		var session = optSession.get();
 		switch (path) {
-			case "user":
-				sendUserAndCookie(ex, session.get());
-				return;
+			case "/authorize":
+				return authorize(ex,session);
+			case "/user":
+				return sendUserAndCookie(ex, session);
 		}
 		System.err.println("not implemented");
-		sendEmptyResponse(HTTP_NOT_FOUND, ex);
+		return sendEmptyResponse(HTTP_NOT_FOUND, ex);
 	}
 
 	private Optional<Session> getSession(HttpExchange ex) {
 		return SessionToken.from(ex).map(SessionToken::sessionId).flatMap(sessions::retrieve);
 	}
 
-	private void sendUserAndCookie(HttpExchange ex, Session session) throws IOException {
+	private boolean openidConfig(HttpExchange ex) throws IOException {
+		var        uri	= ex.getRequestURI().toString();
+		JSONObject json = new JSONObject();
+
+		json.put("authorization_endpoint", prefix(ex) + "/web/authorization.html");
+		return sendContent(ex, json);
+	}
+
+
+	private boolean sendUserAndCookie(HttpExchange ex, Session session) throws IOException {
 		var bytes   = new JSONObject(session.user().map(false)).toString().getBytes(UTF_8);
 		var headers = ex.getResponseHeaders();
 
 		headers.add(CONTENT_TYPE, JSON);
 		new SessionToken(session.id()).addTo(headers);
 		ex.sendResponseHeaders(200, bytes.length);
-		ex.getResponseBody().write(bytes);
+		var out = ex.getResponseBody();
+		out.write(bytes);
+		return true;
 	}
 }

de.srsoftware.oidc.web/src/main/java/de/srsoftware/oidc/web/Forward.java

@@ -14,10 +14,10 @@ public class Forward extends PathHandler {
 	}
 
 	@Override
-	public void handle(HttpExchange ex) throws IOException {
-		System.out.printf("Forwarding (%d) %s to %s…\n", CODE, ex.getRequestURI(), toPath);
+	public boolean doGet(String path, HttpExchange ex) throws IOException {
+		System.out.printf("Forwarding (%d) %s to %s…\n", CODE, path, toPath);
 		ex.getResponseHeaders().add("Location", toPath);
 		ex.sendResponseHeaders(CODE, 0);
-		ex.getResponseBody().close();
+		return true;
 	}
 }

de.srsoftware.oidc.web/src/main/java/de/srsoftware/oidc/web/StaticPages.java

@@ -1,11 +1,12 @@
 /* © SRSoftware 2024 */
 package de.srsoftware.oidc.web;
 
+import static java.net.HttpURLConnection.HTTP_NOT_FOUND;
+
 import com.sun.net.httpserver.HttpExchange;
 import de.srsoftware.oidc.api.PathHandler;
 import java.io.FileNotFoundException;
 import java.io.IOException;
-import java.io.OutputStream;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.nio.file.Files;
@@ -14,6 +15,7 @@ import java.util.Optional;
 
 public class StaticPages extends PathHandler {
 	private static final String DEFAULT_LANGUAGE = "en";
+	private static final String FAVICON          = "favicon.ico";
 	private final Optional<Path> base;
 	private ClassLoader          loader;
 
@@ -27,27 +29,22 @@ public class StaticPages extends PathHandler {
 	private static final String INDEX = "en/index.html";
 
 	@Override
-	public void handle(HttpExchange ex) throws IOException {
-		String relativePath = relativePath(ex);
+	public boolean doGet(String relativePath, HttpExchange ex) throws IOException {
 		String lang = language(ex).orElse(DEFAULT_LANGUAGE);
-		String method	    = ex.getRequestMethod();
-
-		if (relativePath.isBlank()) relativePath = INDEX;
-		System.out.printf("%s %s: ", method, ex.getRequestURI());
+		if (relativePath.startsWith("/")) relativePath = relativePath.substring(1);
+		if (relativePath.isBlank()) {
+			relativePath = ex.getRequestURI().toString().endsWith(FAVICON) ? FAVICON : INDEX;
+		}
 		try {
-			System.out.printf("Loading %s for lagnuage %s…", relativePath, lang);
+			System.out.printf("Loading %s for language %s…", relativePath, lang);
 			Response response = loadFile(lang, relativePath).orElseThrow(() -> new FileNotFoundException());
 
 			ex.getResponseHeaders().add(CONTENT_TYPE, response.contentType);
-			ex.sendResponseHeaders(200, response.content.length);
-			OutputStream os = ex.getResponseBody();
-			os.write(response.content);
-			os.close();
 			System.out.println("success.");
+			return sendContent(ex, response.content);
 		} catch (FileNotFoundException fnf) {
-			ex.sendResponseHeaders(404, 0);
-			ex.getResponseBody().close();
 			System.err.println("failed!");
+			return sendEmptyResponse(HTTP_NOT_FOUND, ex);
 		}
 	}
 

de.srsoftware.oidc.web/src/main/resources/en/authorization.html

@@ -0,0 +1,13 @@
+<html>
+<head>
+    <meta charset="utf-8">
+    <title>Light OIDC</title>
+    <script src="config.js"></script>
+    <script src="user.js"></script>
+    <script src="authorization.js"></script>
+</head>
+<body>
+<h1>Authorization!</h1>
+Not implemented, yet!
+</body>
+</html>

de.srsoftware.oidc.web/src/main/resources/en/authorization.js

@@ -0,0 +1,11 @@
+var params = new URLSearchParams(window.location.search)
+var json = Object.fromEntries(params);
+
+fetch(api+"/authorize",{
+    method: 'POST',
+    body: JSON.stringify(json),
+    headers: {
+        'Content-Type': 'application/json'
+    }
+})
+

de.srsoftware.oidc.web/src/main/resources/en/index.html

@@ -1,10 +1,24 @@
 <html>
     <head>
+        <meta charset="utf-8">
         <title>Light OIDC</title>
         <script src="config.js"></script>
-        <script src="index.js"></script>
+        <script src="user.js"></script>
     </head>
     <body>
         <h1>Welcome!</h1>
+        <h2>Connected sites</h2>
+        These are sites that are connected with your account:
+        <table>
+            <tr>
+                <th>Site</th>
+                <th>Actions</th>
+            </tr>
+            <tr>
+                <td>
+                    <button onclick="window.location.href='newclient.html';">Add new site…</button>
+                </td>
+            </tr>
+        </table>
     </body>
 </html>

de.srsoftware.oidc.web/src/main/resources/en/index.js

@@ -1,7 +0,0 @@
-const UNAUTHORIZED = 401;
-
-function handleUser(response){
-    console.log(response);
-}
-
-fetch(api+"/user").then(handleUser);

de.srsoftware.oidc.web/src/main/resources/en/login.html

@@ -1,25 +1,24 @@
 <html>
     <head>
+        <meta charset="utf-8">
         <title>Light OIDC</title>
         <script src="config.js"></script>
-        <script src="index.js"></script>
+        <script src="login.js"></script>
     </head>
     <body>
         <h1>Login</h1>
-        <form id="login">
-            <fieldset>
+        <fieldset id="login">
             <legend>User credentials</legend>
             <label>
                 Username
-                <input type="text" name="username" />
+                <input type="text" id="username" />
             </label>
             <label>
                 Password
-                <input type="password" name="password" />
+                <input type="password" id="password" />
             </label>
             <button type="button" onClick="tryLogin()">Login</button>
         </fieldset>
-        </form>
         <div id="error"></div>
     </body>
 </html>

de.srsoftware.oidc.web/src/main/resources/en/login.js

@@ -0,0 +1,33 @@
+async function handleLogin(response){
+    if (response.ok){
+        var body = await response.json();
+
+        setTimeout(doRedirect,100);
+    }
+    return false;
+}
+
+function doRedirect(){
+        let params = new URL(document.location.toString()).searchParams;
+        let redirect = params.get("return_to") || 'index.html';
+        window.location.href = redirect,true;
+        return false;
+}
+
+function tryLogin(){
+    document.getElementById("error").innerHTML = "";
+    var username = document.getElementById('username').value;
+    var password = document.getElementById('password').value;
+    fetch(api+"/login",{
+        method: 'POST',
+        headers: {
+          Accept: 'application/json',
+          'Content-Type': 'application/json'
+        },
+        body: JSON.stringify({
+            username : username,
+            password : password
+        })
+    }).then(handleLogin);
+    return false;
+}

de.srsoftware.oidc.web/src/main/resources/en/newclient.html

@@ -0,0 +1,28 @@
+<html>
+<head>
+    <meta charset="utf-8">
+    <title>Light OIDC</title>
+    <script src="config.js"></script>
+    <script src="user.js"></script>
+</head>
+<body>
+<h1>Add new client</h1>
+<fieldset>
+    <legend>Settings</legend>
+    <table>
+        <tr>
+            <th>client name</th>
+            <td><input type="text" size="50" id="client-name"></td>
+        </tr>
+        <tr>
+            <th>client secret</th>
+            <td><input type="text" size="50" id="client-secret"></td>
+        </tr>
+        <tr>
+            <th>redirect urls</th>
+            <td><textarea cols="50" rows="5" id="redirect-urls"></textarea></td>
+        </tr>
+    </table>
+</fieldset>
+</body>
+</html>

de.srsoftware.oidc.web/src/main/resources/en/user.js

@@ -0,0 +1,12 @@
+const UNAUTHORIZED = 401;
+
+async function handleUser(response){
+    if (response.status == UNAUTHORIZED) {
+        window.location.href = 'login.html?return_to='+encodeURI(window.location.href);
+        return;
+    }
+    var user = await response.json();
+    // TODO: load navigation
+}
+
+fetch(api+"/user",{method:'POST'}).then(handleUser);