content: /**
   * 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
   * <p>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p>
   * 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.atlas.security;
  
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.security.alias.CredentialProvider;
  import org.apache.hadoop.security.alias.CredentialProviderFactory;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.IOException;
  
  import static org.apache.atlas.security.SecurityProperties.CERT_STORES_CREDENTIAL_PROVIDER_PATH;
  
  public class SecurityUtil {
      public static final Logger LOG = LoggerFactory.getLogger(SecurityUtil.class);
  
      private SecurityUtil() {
          // to block instantiation
      }
  
      /**
       * Retrieves a password from a configured credential provider or prompts for the password and stores it in the
       * configured credential provider.
       * @param config application configuration
       * @param key the key/alias for the password.
       * @return the password.
       * @throws IOException
       */
      public static String getPassword(org.apache.commons.configuration.Configuration config, String key) throws IOException {
          return getPassword(config, key, CERT_STORES_CREDENTIAL_PROVIDER_PATH);
      }
  
      /**
       * Retrieves a password from a configured credential provider or prompts for the password and stores it in the
       * configured credential provider.
       *
       * @param config           application configuration
       * @param key              the key/alias for the password.
       * @param pathPropertyName property of path
       * @return the password.
       * @throws IOException
       */
      public static String getPassword(org.apache.commons.configuration.Configuration config, String key, String pathPropertyName) throws IOException {
          String password;
          String provider = config.getString(pathPropertyName);
  
          if (provider != null) {
              LOG.info("Attempting to retrieve password for key {} from {} configured credential provider path {}", key, pathPropertyName, provider);
  
              Configuration c = new Configuration();
  
              c.set(CredentialProviderFactory.CREDENTIAL_PROVIDER_PATH, provider);
  
              CredentialProvider                 credentialProvider = CredentialProviderFactory.getProviders(c).get(0);
              CredentialProvider.CredentialEntry entry              = credentialProvider.getCredentialEntry(key);
  
              if (entry == null) {
                  throw new IOException(String.format("No credential entry found for %s. Please create an entry in the configured credential provider", key));
              } else {
                  password = String.valueOf(entry.getCredential());
              }
          } else {
              throw new IOException("No credential provider path " + pathPropertyName + " configured for storage of certificate store passwords");
          }
  
          return password;
      }
  }
  