Add SFTP password authentication tests for Commons VFS2

Author: Vaishnavi Kumbhar

commons-vfs2/src/test/java/org/apache/commons/vfs2/provider/sftp/SftpPasswordAuthTest.java

@@ -0,0 +1,247 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.vfs2.provider.sftp;
+
+import static org.apache.commons.vfs2.VfsTestUtils.getTestDirectoryFile;
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.io.File;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.time.Duration;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.commons.vfs2.*;
+import org.apache.commons.vfs2.auth.StaticUserAuthenticator;
+import org.apache.commons.vfs2.impl.DefaultFileSystemConfigBuilder;
+import org.apache.commons.vfs2.impl.DefaultFileSystemManager;
+import org.apache.commons.vfs2.provider.local.DefaultLocalFileProvider;
+import org.apache.sshd.SshServer;
+import org.apache.sshd.common.KeyPairProvider;
+import org.apache.sshd.common.NamedFactory;
+import org.apache.sshd.common.Session;
+import org.apache.sshd.server.Command;
+import org.apache.sshd.server.FileSystemFactory;
+import org.apache.sshd.server.FileSystemView;
+import org.apache.sshd.server.SshFile;
+import org.apache.sshd.server.filesystem.NativeSshFile;
+import org.apache.sshd.server.sftp.SftpSubsystem;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import com.jcraft.jsch.TestIdentityRepositoryFactory;
+
+/**
+ * Tests SFTP password authentication using {@link StaticUserAuthenticator}.
+ * <p>
+ * Verifies that credentials supplied via {@link DefaultFileSystemConfigBuilder#setUserAuthenticator}
+ * are correctly propagated to the SFTP server.
+ * </p>
+ * <p>
+ * Uses SSHD 0.8.0 with an explicit RSA {@link KeyPairProvider} for Java 17 compatibility
+ * (the default DSA key generation is disabled on modern JDKs).
+ * </p>
+ */
+public class SftpPasswordAuthTest {
+
+    private static final String TEST_USERNAME = "testuser";
+    private static final String TEST_PASSWORD = "testpass";
+
+    private static SshServer sshServer;
+    private static int serverPort;
+    private static DefaultFileSystemManager manager;
+
+    @BeforeAll
+    static void setUp() throws Exception {
+        sshServer = SshServer.setUpDefaultServer();
+        sshServer.setPort(0);
+
+        final KeyPairGenerator hostKeyGen = KeyPairGenerator.getInstance("RSA");
+        hostKeyGen.initialize(2048);
+        final KeyPair hostKey = hostKeyGen.generateKeyPair();
+        sshServer.setKeyPairProvider(new KeyPairProvider() {
+            @Override
+            public KeyPair loadKey(final String type) {
+                return KeyPairProvider.SSH_RSA.equals(type) ? hostKey : null;
+            }
+            @Override
+            public String getKeyTypes() {
+                return KeyPairProvider.SSH_RSA;
+            }
+        });
+
+        sshServer.setPasswordAuthenticator(
+                (user, pass, session) -> TEST_USERNAME.equals(user) && TEST_PASSWORD.equals(pass));
+
+        final List<NamedFactory<Command>> subsystems = new ArrayList<>();
+        subsystems.add(new NamedFactory<Command>() {
+            @Override
+            public Command create() { return new SftpSubsystem(); }
+            @Override
+            public String getName() { return "sftp"; }
+        });
+        sshServer.setSubsystemFactories(subsystems);
+
+        sshServer.setFileSystemFactory(new TestFileSystemFactory());
+        sshServer.start();
+
+        serverPort = sshServer.getPort();
+
+        manager = new DefaultFileSystemManager();
+        manager.addProvider("sftp", new SftpFileProvider());
+        manager.addProvider("file", new DefaultLocalFileProvider());
+        manager.init();
+    }
+
+    @AfterAll
+    static void tearDown() throws Exception {
+        if (manager != null) {
+            try {
+                manager.close();
+            } catch (final Exception e) {
+                // ignore
+            }
+        }
+        if (sshServer != null) {
+            stopServerWithTimeout(5000);
+        }
+    }
+
+    private static void stopServerWithTimeout(final long timeoutMs) {
+        final Thread stopThread = new Thread(() -> {
+            try {
+                sshServer.stop(true);
+            } catch (final Exception e) {
+                // ignore
+            }
+        }, "sshd-stop");
+        stopThread.setDaemon(true);
+        stopThread.start();
+        try {
+            stopThread.join(timeoutMs);
+        } catch (final InterruptedException e) {
+            Thread.currentThread().interrupt();
+        }
+    }
+
+    private static String baseUri() {
+        return String.format("sftp://%s@localhost:%d", TEST_USERNAME, serverPort);
+    }
+
+    private FileSystemOptions authOptions() throws FileSystemException {
+        final FileSystemOptions opts = new FileSystemOptions();
+        final StaticUserAuthenticator auth = new StaticUserAuthenticator(null, TEST_USERNAME, TEST_PASSWORD);
+        DefaultFileSystemConfigBuilder.getInstance().setUserAuthenticator(opts, auth);
+        configureSftpOptions(opts);
+        return opts;
+    }
+
+    private static void configureSftpOptions(final FileSystemOptions opts) throws FileSystemException {
+        final SftpFileSystemConfigBuilder builder = SftpFileSystemConfigBuilder.getInstance();
+        builder.setStrictHostKeyChecking(opts, "no");
+        builder.setUserInfo(opts, new TrustEveryoneUserInfo());
+        builder.setIdentityRepositoryFactory(opts, new TestIdentityRepositoryFactory());
+        builder.setConnectTimeout(opts, Duration.ofSeconds(60));
+        builder.setSessionTimeout(opts, Duration.ofSeconds(60));
+    }
+
+    @Test
+    void testResolveFile() throws FileSystemException {
+        final FileSystemOptions opts = authOptions();
+        try (FileObject file = manager.resolveFile(baseUri() + "/read-tests/file1.txt", opts)) {
+            assertNotNull(file);
+            assertTrue(file.exists(), "file1.txt should exist");
+            assertEquals(FileType.FILE, file.getType());
+            assertNotNull(file.getContent(), "Content should be readable when credentials are correct");
+        }
+    }
+
+    @Test
+    void testResolveFolder() throws FileSystemException {
+        final FileSystemOptions opts = authOptions();
+        try (FileObject folder = manager.resolveFile(baseUri() + "/read-tests", opts)) {
+            assertNotNull(folder);
+            assertTrue(folder.exists(), "read-tests folder should exist");
+        }
+    }
+
+    @Test
+    void testResolveFolderWithTrailingSlash() throws FileSystemException {
+        final FileSystemOptions opts = authOptions();
+        try (FileObject folder = manager.resolveFile(baseUri() + "/read-tests/", opts)) {
+            assertNotNull(folder);
+            assertTrue(folder.exists(), "read-tests/ folder should exist");
+        }
+    }
+
+    @Test
+    void testWrongCredentialsThrowsException() throws FileSystemException {
+        final FileSystemOptions opts = new FileSystemOptions();
+        final StaticUserAuthenticator auth = new StaticUserAuthenticator(null, "wronguser", "wrongpassword");
+        DefaultFileSystemConfigBuilder.getInstance().setUserAuthenticator(opts, auth);
+        configureSftpOptions(opts);
+
+        final String wrongUserUri = String.format("sftp://wronguser@localhost:%d/read-tests/file1.txt", serverPort);
+        assertThrows(FileSystemException.class, () -> {
+            try (FileObject file = manager.resolveFile(wrongUserUri, opts)) {
+                file.exists();
+            }
+        }, "Expected FileSystemException when accessing a resource with wrong credentials");
+    }
+    
+    private static class TestFileSystemFactory implements FileSystemFactory {
+        @Override
+        public FileSystemView createFileSystemView(final Session session) {
+            final String home = getTestDirectoryFile().getAbsolutePath();
+            final String user = session.getUsername();
+            return new FileSystemView() {
+                @Override
+                public SshFile getFile(final SshFile baseDir, final String file) {
+                    return getFile(baseDir.getAbsolutePath(), file);
+                }
+                @Override
+                public SshFile getFile(final String file) {
+                    return getFile(home, file);
+                }
+                private SshFile getFile(final String dir, final String file) {
+                    final String normalized = NativeSshFile.normalizeSeparateChar(file);
+                    final String homeNorm = NativeSshFile.normalizeSeparateChar(home);
+                    final String prefix = removePrefix(homeNorm);
+                    String userFile = removePrefix(normalized);
+                    final File f = userFile.startsWith(prefix)
+                            ? new File(userFile)
+                            : new File(prefix, userFile);
+                    userFile = removePrefix(NativeSshFile.normalizeSeparateChar(f.getAbsolutePath()));
+                    return new AccessibleNativeSshFile(userFile, f, user);
+                }
+                private String removePrefix(final String s) {
+                    final int idx = s.indexOf('/');
+                    return idx < 1 ? s : s.substring(idx);
+                }
+            };
+        }
+    }
+
+    private static class AccessibleNativeSshFile extends NativeSshFile {
+        AccessibleNativeSshFile(final String fileName, final File file, final String userName) {
+            super(fileName, file, userName);
+        }
+    }
+}