netconf/netconf-netty-util/src/main/java/org/opendaylight/netconf/nettyutil/handler/ssh/client/NetconfClientBuilder.java

   1 /*
   2  * Copyright (c) 2019 PANTHEON.tech, s.r.o. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.netconf.nettyutil.handler.ssh.client;
   9
  10 import static com.google.common.base.Verify.verify;
  11
  12 import com.google.common.annotations.Beta;
  13 import com.google.common.collect.ImmutableList;
  14 import com.google.common.collect.Streams;
  15 import java.util.Arrays;
  16 import org.opendaylight.netconf.shaded.sshd.client.ClientBuilder;
  17 import org.opendaylight.netconf.shaded.sshd.client.SshClient;
  18 import org.opendaylight.netconf.shaded.sshd.common.NamedFactory;
  19 import org.opendaylight.netconf.shaded.sshd.common.signature.BuiltinSignatures;
  20 import org.opendaylight.netconf.shaded.sshd.common.signature.Signature;
  21
  22 /**
  23  * A {@link ClientBuilder} which builds {@link NetconfSshClient} instances.
  24  */
  25 @Beta
  26 public class NetconfClientBuilder extends ClientBuilder {
  27     // RFC8332 rsa-sha2-256/rsa-sha2-512 are not a part of Mina's default set of signatures for clients as of 2.5.1.
  28     // Add them to ensure interop with modern highly-secured devices.
  29     private static final ImmutableList<NamedFactory<Signature>> FULL_SIGNATURE_PREFERENCE =
  30             Streams.concat(DEFAULT_SIGNATURE_PREFERENCE.stream(), Arrays.asList(
  31                 BuiltinSignatures.rsaSHA512_cert, BuiltinSignatures.rsaSHA256_cert,
  32                 BuiltinSignatures.rsaSHA512, BuiltinSignatures.rsaSHA256).stream())
  33             .filter(BuiltinSignatures::isSupported)
  34             .distinct()
  35             .collect(ImmutableList.<NamedFactory<Signature>>toImmutableList());
  36
  37     @Override
  38     public NetconfSshClient build() {
  39         final SshClient client = super.build();
  40         verify(client instanceof NetconfSshClient, "Unexpected client %s", client);
  41         return (NetconfSshClient) client;
  42     }
  43
  44     @Override
  45     protected ClientBuilder fillWithDefaultValues() {
  46         if (factory == null) {
  47             factory = NetconfSshClient.DEFAULT_NETCONF_SSH_CLIENT_FACTORY;
  48         }
  49         if (signatureFactories == null) {
  50             signatureFactories = FULL_SIGNATURE_PREFERENCE;
  51         }
  52         return super.fillWithDefaultValues();
  53     }
  54 }