[AI] Fix ThreadedServerWorkflowExecutor with DTLS protocols

TLS-Core/src/main/java/de/rub/nds/tlsattacker/core/workflow/WorkflowExecutorFactory.java

@@ -18,6 +18,15 @@ public static WorkflowExecutor createWorkflowExecutor(WorkflowExecutorType type,
             case DEFAULT:
                 return new DefaultWorkflowExecutor(state);
             case THREADED_SERVER:
+                if (state.getConfig().getHighestProtocolVersion() != null
+                        && state.getConfig().getHighestProtocolVersion().isDTLS()) {
+                    throw new UnsupportedOperationException(
+                            "ThreadedServerWorkflowExecutor is not supported for DTLS protocols. "
+                                    + "For UDP/DTLS, Java's DatagramSocket API does not allow spawning "
+                                    + "new sockets for each client connection. Use the default DTLS "
+                                    + "executor instead by removing the -executor_type parameter or "
+                                    + "setting it to DTLS.");
+                }
                 return new ThreadedServerWorkflowExecutor(state);
             case DTLS:
                 return new DTLSWorkflowExecutor(state);

TLS-Core/src/test/java/de/rub/nds/tlsattacker/core/workflow/WorkflowExecutorFactoryTest.java

@@ -0,0 +1,108 @@
+/*
+ * TLS-Attacker - A Modular Penetration Testing Framework for TLS
+ *
+ * Copyright 2014-2023 Ruhr University Bochum, Paderborn University, Technology Innovation Institute, and Hackmanit GmbH
+ *
+ * Licensed under Apache License, Version 2.0
+ * http://www.apache.org/licenses/LICENSE-2.0.txt
+ */
+package de.rub.nds.tlsattacker.core.workflow;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import de.rub.nds.tlsattacker.core.config.Config;
+import de.rub.nds.tlsattacker.core.constants.ProtocolVersion;
+import de.rub.nds.tlsattacker.core.state.State;
+import de.rub.nds.tlsattacker.core.workflow.action.executor.WorkflowExecutorType;
+import org.junit.jupiter.api.Test;
+
+public class WorkflowExecutorFactoryTest {
+
+    @Test
+    public void testCreateDefaultExecutor() {
+        Config config = new Config();
+        State state = new State(config);
+        WorkflowExecutor executor =
+                WorkflowExecutorFactory.createWorkflowExecutor(WorkflowExecutorType.DEFAULT, state);
+        assertNotNull(executor);
+        assertTrue(executor instanceof DefaultWorkflowExecutor);
+    }
+
+    @Test
+    public void testCreateDtlsExecutor() {
+        Config config = new Config();
+        State state = new State(config);
+        WorkflowExecutor executor =
+                WorkflowExecutorFactory.createWorkflowExecutor(WorkflowExecutorType.DTLS, state);
+        assertNotNull(executor);
+        assertTrue(executor instanceof DTLSWorkflowExecutor);
+    }
+
+    @Test
+    public void testCreateThreadedServerExecutorWithTls() {
+        Config config = new Config();
+        config.setHighestProtocolVersion(ProtocolVersion.TLS12);
+        State state = new State(config);
+        WorkflowExecutor executor =
+                WorkflowExecutorFactory.createWorkflowExecutor(
+                        WorkflowExecutorType.THREADED_SERVER, state);
+        assertNotNull(executor);
+        assertTrue(executor instanceof ThreadedServerWorkflowExecutor);
+    }
+
+    @Test
+    public void testThreadedServerExecutorWithDtlsThrowsException() {
+        Config config = new Config();
+        config.setHighestProtocolVersion(ProtocolVersion.DTLS12);
+        State state = new State(config);
+
+        UnsupportedOperationException exception =
+                assertThrows(
+                        UnsupportedOperationException.class,
+                        () ->
+                                WorkflowExecutorFactory.createWorkflowExecutor(
+                                        WorkflowExecutorType.THREADED_SERVER, state));
+
+        assertTrue(
+                exception
+                        .getMessage()
+                        .contains("ThreadedServerWorkflowExecutor is not supported for DTLS"));
+        assertTrue(exception.getMessage().contains("DatagramSocket API"));
+    }
+
+    @Test
+    public void testThreadedServerExecutorWithDtls10ThrowsException() {
+        Config config = new Config();
+        config.setHighestProtocolVersion(ProtocolVersion.DTLS10);
+        State state = new State(config);
+
+        UnsupportedOperationException exception =
+                assertThrows(
+                        UnsupportedOperationException.class,
+                        () ->
+                                WorkflowExecutorFactory.createWorkflowExecutor(
+                                        WorkflowExecutorType.THREADED_SERVER, state));
+
+        assertTrue(
+                exception
+                        .getMessage()
+                        .contains("ThreadedServerWorkflowExecutor is not supported for DTLS"));
+    }
+
+    @Test
+    public void testThreadedServerExecutorWithNullProtocolVersion() {
+        Config config = new Config();
+        config.setHighestProtocolVersion(null);
+        // Pass a pre-defined workflow trace to avoid State creating a default one which requires
+        // protocol version
+        WorkflowTrace trace = new WorkflowTrace();
+        State state = new State(config, trace);
+
+        // Should not throw exception when protocol version is null
+        WorkflowExecutor executor =
+                WorkflowExecutorFactory.createWorkflowExecutor(
+                        WorkflowExecutorType.THREADED_SERVER, state);
+        assertNotNull(executor);
+        assertTrue(executor instanceof ThreadedServerWorkflowExecutor);
+    }
+}