NIFI-14068 Fix Domain Name Handling for SFTP Proxy Access

nifi-extension-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/ssh/StandardSSHClient.java

@@ -0,0 +1,56 @@
+/*
+ * 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
+ *
+ *     http://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.nifi.processors.standard.ssh;
+
+import com.exceptionfactory.socketbroker.BrokeredSocketFactory;
+import net.schmizz.sshj.Config;
+import net.schmizz.sshj.SSHClient;
+import org.apache.nifi.processors.standard.socket.ProxySocketFactory;
+
+import javax.net.SocketFactory;
+import java.net.InetSocketAddress;
+
+/**
+ * Standard extension of SSHJ SSHClient supporting unresolved Socket Addresses for control over proxy behavior
+ */
+public class StandardSSHClient extends SSHClient {
+
+    public StandardSSHClient(final Config config) {
+        super(config);
+    }
+
+    /**
+     * Create InetSocketAddress to based on proxy configuration
+     *
+     * @param hostname Hostname or Internet Protocol address
+     * @param port TCP port number
+     * @return Socket Address resolved or unresolved based on proxy configuration
+     */
+    @Override
+    protected InetSocketAddress makeInetSocketAddress(final String hostname, final int port) {
+        final SocketFactory socketFactory = getSocketFactory();
+        final boolean proxyConfigured = socketFactory instanceof ProxySocketFactory || socketFactory instanceof BrokeredSocketFactory;
+
+        final InetSocketAddress socketAddress;
+        if (proxyConfigured) {
+            socketAddress = InetSocketAddress.createUnresolved(hostname, port);
+        } else {
+            socketAddress = new InetSocketAddress(hostname, port);
+        }
+        return socketAddress;
+    }
+}

nifi-extension-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/ssh/StandardSSHClientProvider.java

@@ -97,7 +97,7 @@ public SSHClient getClient(final PropertyContext context, final Map<String, Stri
         final List<AuthMethod> authMethods = getPasswordAuthMethods(context, attributes);
 
         final Config config = SSH_CONFIG_PROVIDER.getConfig(address, context);
-        final SSHClient client = new SSHClient(config);
+        final SSHClient client = new StandardSSHClient(config);
 
         try {
             setClientProperties(client, context);

nifi-extension-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/java/org/apache/nifi/processors/standard/ssh/StandardSSHClientTest.java

@@ -0,0 +1,64 @@
+/*
+ * 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
+ *
+ *     http://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.nifi.processors.standard.ssh;
+
+import net.schmizz.sshj.DefaultConfig;
+import org.apache.nifi.processors.standard.socket.ProxySocketFactory;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.Proxy;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class StandardSSHClientTest {
+    private static final String HOSTNAME = "localhost";
+
+    private static final int PORT = 22;
+
+    private static final int PROXY_PORT = 8080;
+
+    @Test
+    void testMakeInetSocketAddressResolved() throws IOException {
+        try (StandardSSHClient client = new StandardSSHClient(new DefaultConfig())) {
+            final InetSocketAddress address = client.makeInetSocketAddress(HOSTNAME, PORT);
+
+            assertFalse(address.isUnresolved());
+            assertEquals(PORT, address.getPort());
+            assertEquals(HOSTNAME, address.getHostString());
+        }
+    }
+
+    @Test
+    void testMakeInetSocketAddressUnresolved() throws IOException {
+        final InetSocketAddress proxyAddress = InetSocketAddress.createUnresolved(HOSTNAME, PROXY_PORT);
+        final Proxy proxy = new Proxy(Proxy.Type.HTTP, proxyAddress);
+        final ProxySocketFactory proxySocketFactory = new ProxySocketFactory(proxy);
+
+        try (StandardSSHClient client = new StandardSSHClient(new DefaultConfig())) {
+            client.setSocketFactory(proxySocketFactory);
+            final InetSocketAddress address = client.makeInetSocketAddress(HOSTNAME, PORT);
+
+            assertTrue(address.isUnresolved());
+            assertEquals(PORT, address.getPort());
+            assertEquals(HOSTNAME, address.getHostString());
+        }
+    }
+}