content: /*
   * Copyright (C)2009 - SSHJ Contributors
   *
   * Licensed 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 com.codeages.termiusplus.biz.server.service.impl;
  
  import net.schmizz.sshj.common.Buffer;
  import net.schmizz.sshj.common.Message;
  import net.schmizz.sshj.common.SSHPacket;
  import net.schmizz.sshj.transport.TransportException;
  import net.schmizz.sshj.userauth.UserAuthException;
  import net.schmizz.sshj.userauth.method.AbstractAuthMethod;
  import net.schmizz.sshj.userauth.method.ChallengeResponseProvider;
  
  /**
   * Implements the {@code keyboard-interactive} authentication method.
   */
  public class CurrentAuthKeyboardInteractive
          extends AbstractAuthMethod {
  
      private final ChallengeResponseProvider provider;
  
      public CurrentAuthKeyboardInteractive(ChallengeResponseProvider provider) {
          super("keyboard-interactive");
          this.provider = provider;
      }
  
      @Override
      public SSHPacket buildReq()
              throws UserAuthException {
          return super.buildReq() // the generic stuff
                      .putString("") // lang-tag
                      .putString(buildCommaSeparatedSubmethodList());
      }
  
      private String buildCommaSeparatedSubmethodList() {
          StringBuilder sb = new StringBuilder();
          for (String submethod : provider.getSubmethods()) {
              if (sb.length() > 0)
                  sb.append(",");
              sb.append(submethod);
          }
          return sb.toString();
      }
  
      private static class CharArrWrap {
  
          private final char[] arr;
  
          private CharArrWrap(char[] arr) {
              this.arr = arr;
          }
      }
  
      @Override
      public void handle(Message cmd, SSHPacket buf)
              throws UserAuthException, TransportException {
          if (cmd != Message.USERAUTH_60) {
              super.handle(cmd, buf);
          } else {
              final CharArrWrap[] userReplies;
              try {
                  provider.init(makeAccountResource(), buf.readString(), buf.readString());
                  buf.readString(); // lang-tag
                  final int numPrompts = buf.readUInt32AsInt();
                  userReplies = new CharArrWrap[numPrompts];
                  for (int i = 0; i < numPrompts; i++) {
                      final String prompt = buf.readString();
                      final boolean echo = buf.readBoolean();
                      log.info("Requesting response for challenge `{}`; echo={}", prompt, echo);
                      userReplies[i] = new CharArrWrap(provider.getResponse(prompt, false));
                  }
              } catch (Buffer.BufferException be) {
                  throw new UserAuthException(be);
              }
              respond(userReplies);
          }
      }
  
      private void respond(CharArrWrap[] userReplies)
              throws TransportException {
          final SSHPacket pkt = new SSHPacket(Message.USERAUTH_INFO_RESPONSE).putUInt32(userReplies.length);
          for (final CharArrWrap response : userReplies)
              pkt.putSensitiveString(response.arr);
          params.getTransport().write(pkt);
      }
  
      @Override
      public boolean shouldRetry() {
          return provider.shouldRetry();
      }
  
  }
  