GP-1481 add support for cancelling hung Ghidra Server connect attempt

Ghidra/Framework/FileSystem/src/main/java/ghidra/framework/client/ClientUtil.java

@@ -32,9 +32,9 @@ import ghidra.framework.remote.*;
 import ghidra.framework.remote.security.SSHKeyManager;
 import ghidra.net.*;
 import ghidra.util.*;
-import ghidra.util.exception.AssertException;
-import ghidra.util.exception.UserAccessException;
+import ghidra.util.exception.*;
 import ghidra.util.task.TaskLauncher;
+import ghidra.util.task.TaskMonitor;
 
 /**
  * <code>ClientUtil</code> allows a user to connect to a Repository Server and obtain its handle.
@@ -294,16 +294,19 @@ public class ClientUtil {
 
 	/**
 	 * Connect to a Ghidra Server and verify compatibility.  This method can be used
-	 * to affectively "ping" the Ghidra Server to verify the ability to connect.
+	 * to effectively "ping" the Ghidra Server to verify the ability to connect.
 	 * NOTE: Use of this method when PKI authentication is enabled is not supported.
 	 * @param host server hostname
 	 * @param port first Ghidra Server port (0=use default)
+	 * @param monitor cancellable monitor
 	 * @throws IOException thrown if an IO Error occurs (e.g., server not found).
 	 * @throws RemoteException if server interface is incompatible or another server-side
 	 * error occurs.
+	 * @throws CancelledException if connection attempt was cancelled
 	 */
-	public static void checkGhidraServer(String host, int port) throws IOException {
-		ServerConnectTask.getGhidraServerHandle(new ServerInfo(host, port));
+	public static void checkGhidraServer(String host, int port, TaskMonitor monitor)
+			throws IOException, CancelledException {
+		ServerConnectTask.getGhidraServerHandle(new ServerInfo(host, port), monitor);
 	}
 
 	/**
@@ -319,24 +322,28 @@ public class ClientUtil {
 	 * @throws GeneralSecurityException if server authentication fails due to
 	 * credential access error (e.g., PKI cert failure)
 	 * @throws IOException thrown if an IO Error occurs.
+	 * @throws CancelledException if connection cancelled by user (does not apply to Headless use)
 	 */
 	static RemoteRepositoryServerHandle connect(ServerInfo server)
-			throws LoginException, GeneralSecurityException, IOException {
+			throws LoginException, GeneralSecurityException, IOException, CancelledException {
 
 		getClientAuthenticator();
 		boolean allowLoginRetry = (clientAuthenticator instanceof DefaultClientAuthenticator);
 
 		RemoteRepositoryServerHandle hdl = null;
 		ServerConnectTask connectTask = new ServerConnectTask(server, allowLoginRetry);
-		if (!SystemUtilities.isInHeadlessMode() && SystemUtilities.isEventDispatchThread()) {
-			// Must be done in modal dialog to allow possible authentication prompts
-			// from another thread.
-
-			TaskLauncher.launch(connectTask);
+		if (SystemUtilities.isInHeadlessMode()) {
+			connectTask.run(TaskMonitor.DUMMY); // headless - can't cancel
 		}
 		else {
-			connectTask.run(null);
+			// Must be done in modal dialog to allow cancellation and possible authentication prompts
+			// from another thread.
+			TaskLauncher.launch(connectTask);
+			if (connectTask.isCancelled()) {
+				throw new CancelledException();
+			}
 		}
+
 		hdl = connectTask.getRepositoryServerHandle();
 		if (hdl == null) {
 			Exception e = connectTask.getException();

Ghidra/Framework/FileSystem/src/main/java/ghidra/framework/client/RepositoryServerAdapter.java

@@ -137,7 +137,13 @@ public class RepositoryServerAdapter {
 
 		Throwable cause = null;
 		try {
-			serverHandle = ClientUtil.connect(server);
+			try {
+				serverHandle = ClientUtil.connect(server);
+			}
+			catch (CancelledException e) {
+				// ignore
+				Msg.debug(this, "Server connect cancelled by user");
+			}
 			unexpectedDisconnect = false;
 			if (serverHandle != null) {
 				Msg.info(this, "Connected to Ghidra Server at " + serverInfoStr);

Ghidra/Framework/FileSystem/src/main/java/ghidra/framework/client/ServerConnectTask.java

@@ -15,7 +15,9 @@
  */
 package ghidra.framework.client;
 
+import java.io.Closeable;
 import java.io.IOException;
+import java.net.Socket;
 import java.net.UnknownHostException;
 import java.rmi.*;
 import java.rmi.registry.LocateRegistry;
@@ -36,8 +38,8 @@ import ghidra.framework.model.ServerInfo;
 import ghidra.framework.remote.*;
 import ghidra.net.ApplicationKeyManagerFactory;
 import ghidra.util.Msg;
-import ghidra.util.task.Task;
-import ghidra.util.task.TaskMonitor;
+import ghidra.util.exception.CancelledException;
+import ghidra.util.task.*;
 
 /**
  * Task for connecting to server with Swing thread.
@@ -56,7 +58,7 @@ class ServerConnectTask extends Task {
 	 * @param allowLoginRetry true if login retry allowed during authentication
 	 */
 	ServerConnectTask(ServerInfo server, boolean allowLoginRetry) {
-		super("Connecting to " + server.getServerName(), false, false, true);
+		super("Connecting to " + server.getServerName(), true, false, true);
 		this.server = server;
 		this.allowLoginRetry = allowLoginRetry;
 	}
@@ -64,12 +66,14 @@ class ServerConnectTask extends Task {
 	/**
 	 * Completes and necessary authentication and obtains a repository handle.
 	 * If a connection error occurs, an exception will be stored ({@link #getException()}.
+	 * @throws CancelledException if task cancelled
 	 * @see ghidra.util.task.Task#run(ghidra.util.task.TaskMonitor)
 	 */
 	@Override
-	public void run(TaskMonitor monitor) {
+	public void run(TaskMonitor monitor) throws CancelledException {
+		monitor = TaskMonitor.dummyIfNull(monitor);
 		try {
-			hdl = getRepositoryServerHandle(ClientUtil.getUserName());
+			hdl = getRepositoryServerHandle(ClientUtil.getUserName(), monitor);
 		}
 		catch (RemoteException e) {
 			exc = e;
@@ -81,6 +85,12 @@ class ServerConnectTask extends Task {
 		catch (Exception e) {
 			exc = e;
 		}
+		finally {
+			if (monitor.isCancelled()) {
+				exc = null;
+				throw new CancelledException();
+			}
+		}
 	}
 
 	/**
@@ -142,18 +152,25 @@ class ServerConnectTask extends Task {
 	/**
 	 * Obtain a remote instance of the Ghidra Server Handle object
 	 * @param server server information
+	 * @param monitor cancellable monitor
 	 * @return Ghidra Server Handle object
 	 * @throws IOException
+	 * @throws CancelledException 
 	 */
-	public static GhidraServerHandle getGhidraServerHandle(ServerInfo server) throws IOException {
+	public static GhidraServerHandle getGhidraServerHandle(ServerInfo server, TaskMonitor monitor)
+			throws IOException, CancelledException {
 
 		GhidraServerHandle gsh = null;
+		boolean canCancel = monitor.isCancelEnabled(); // original state
 		try {
 			// Test SSL Handshake to ensure that user is able to decrypt keystore.
 			// This is intended to work around an RMI issue where a continuous
 			// retry condition can occur when a user cancels the password entry
 			// for their keystore which should cancel any connection attempt
-			testServerSSLConnection(server);
+			testServerSSLConnection(server, monitor);
+
+			monitor.setCancelEnabled(false);
+			monitor.setMessage("Connecting...");
 
 			Registry reg;
 			try {
@@ -191,20 +208,50 @@ class ServerConnectTask extends Task {
 			}
 			throw e;
 		}
+		finally {
+			monitor.setCancelEnabled(canCancel);
+			monitor.setMessage("");
+		}
 		return gsh;
 	}
 
+	private static class ConnectCancelledListener implements CancelledListener, Closeable {
+
+		private TaskMonitor monitor;
+		private CancelledListener callback;
+
+		ConnectCancelledListener(TaskMonitor monitor, CancelledListener callback) {
+			this.monitor = monitor;
+			this.callback = callback;
+			monitor.addCancelledListener(this);
+		}
+
+		@Override
+		public void cancelled() {
+			if (callback != null) {
+				callback.cancelled();
+			}
+		}
+
+		@Override
+		public void close() throws IOException {
+			monitor.removeCancelledListener(this);
+		}
+	}
+
 	/**
 	 * Attempts server connection and completes any necessary authentication.
 	 * @param defaultUserID
-	 * @return server handle or null if authentication was cancelled by user
+	 * @param monitor task monitor for connection cancellation
+	 * @return server handle or null if authentication or connection attempt was cancelled by user
 	 * @throws IOException 
 	 * @throws LoginException 
 	 */
-	private RemoteRepositoryServerHandle getRepositoryServerHandle(String defaultUserID)
-			throws IOException, LoginException {
+	private RemoteRepositoryServerHandle getRepositoryServerHandle(String defaultUserID,
+			TaskMonitor monitor)
+			throws IOException, LoginException, CancelledException {
 
-		GhidraServerHandle gsh = getGhidraServerHandle(server);
+		GhidraServerHandle gsh = getGhidraServerHandle(server, monitor);
 		if (gsh == null) {
 			return null;
 		}
@@ -318,19 +365,37 @@ class ServerConnectTask extends Task {
 		}
 	}
 
-	private static void testServerSSLConnection(ServerInfo server) throws IOException {
+	private static void forceClose(Socket s) {
+		try {
+			s.close();
+		}
+		catch (IOException e) {
+			// ignore
+		}
+	}
+
+	private static void testServerSSLConnection(ServerInfo server, TaskMonitor monitor)
+			throws IOException, CancelledException {
 
 		RMIServerPortFactory portFactory = new RMIServerPortFactory(server.getPortNumber());
 		SslRMIClientSocketFactory factory = new SslRMIClientSocketFactory();
 		String serverName = server.getServerName();
 		int sslRmiPort = portFactory.getRMISSLPort();
 
-		try (SSLSocket socket = (SSLSocket) factory.createSocket(serverName, sslRmiPort)) {
+		monitor.setCancelEnabled(true);
+		monitor.setMessage("Checking Server Liveness...");
+
+		try (SSLSocket socket = (SSLSocket) factory.createSocket(serverName, sslRmiPort);
+				ConnectCancelledListener cancelListener =
+					new ConnectCancelledListener(monitor, () -> forceClose(socket))) {
 			// Complete SSL handshake to trigger client keystore access if required
 			// which will give user ability to cancel without involving RMI which 
 			// will avoid RMI reconnect attempts
 			socket.startHandshake();
 		}
+		finally {
+			monitor.checkCanceled(); // circumvent any IOException which may have occured
+		}
 	}
 
 	private static void checkServerBindNames(Registry reg) throws RemoteException {

Ghidra/Test/IntegrationTest/src/test.slow/java/ghidra/framework/client/GhidraServerSerialFilterFailureTest.java

@@ -36,6 +36,7 @@ import ghidra.framework.remote.GhidraServerHandle;
 import ghidra.net.ApplicationKeyManagerFactory;
 import ghidra.server.remote.ServerTestUtil;
 import ghidra.test.AbstractGhidraHeadlessIntegrationTest;
+import ghidra.util.task.TaskMonitor;
 import utilities.util.FileUtilities;
 
 @Category(PortSensitiveCategory.class)
@@ -110,7 +111,8 @@ public class GhidraServerSerialFilterFailureTest extends AbstractGhidraHeadlessI
 
 		ServerInfo server = new ServerInfo("localhost", ServerTestUtil.GHIDRA_TEST_SERVER_PORT);
 		
-		GhidraServerHandle serverHandle = ServerConnectTask.getGhidraServerHandle(server);
+		GhidraServerHandle serverHandle =
+			ServerConnectTask.getGhidraServerHandle(server, TaskMonitor.DUMMY);
 		
 		try {
 			serverHandle.getRepositoryServer(getBogusUserSubject(), new Callback[0]);