/*

  * This file is part of dependency-check-core.

  *

  * 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.

  *

  * Copyright (c) 2014 Jeremy Long. All Rights Reserved.

  */

 package org.owasp.dependencycheck.analyzer;

 import org.apache.commons.io.FileUtils;

 import org.owasp.dependencycheck.Engine;

 import org.owasp.dependencycheck.analyzer.exception.AnalysisException;

 import org.owasp.dependencycheck.data.central.CentralSearch;

 import org.owasp.dependencycheck.data.nexus.MavenArtifact;

 import org.owasp.dependencycheck.dependency.Confidence;

 import org.owasp.dependencycheck.dependency.Dependency;

 import org.owasp.dependencycheck.dependency.Evidence;

 import org.owasp.dependencycheck.xml.pom.PomUtils;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import java.io.File;

 import java.io.FileFilter;

 import java.io.FileNotFoundException;

 import java.io.IOException;

 import java.net.MalformedURLException;

 import java.net.URL;

 import java.util.List;

 import org.owasp.dependencycheck.exception.InitializationException;

 import org.owasp.dependencycheck.utils.DownloadFailedException;

 import org.owasp.dependencycheck.utils.Downloader;

 import org.owasp.dependencycheck.utils.FileFilterBuilder;

 import org.owasp.dependencycheck.utils.InvalidSettingException;

 import org.owasp.dependencycheck.utils.Settings;

 /**

  * Analyzer which will attempt to locate a dependency, and the GAV information,

  * by querying Central for the dependency's SHA-1 digest.

  *

  * @author colezlaw

  */

 public class CentralAnalyzer extends AbstractFileTypeAnalyzer {

     /**

      * The logger.

      */

     private static final Logger LOGGER = LoggerFactory.getLogger(CentralAnalyzer.class);

     /**

      * The name of the analyzer.

      */

     private static final String ANALYZER_NAME = "Central Analyzer";

     /**

      * The phase in which this analyzer runs.

      */

     private static final AnalysisPhase ANALYSIS_PHASE = AnalysisPhase.INFORMATION_COLLECTION;

     /**

      * The types of files on which this will work.

      */

     private static final String SUPPORTED_EXTENSIONS = "jar";

     /**

      * The analyzer should be disabled if there are errors, so this is a flag to

      * determine if such an error has occurred.

      */

     private volatile boolean errorFlag = false;

     /**

      * The searcher itself.

      */

     private CentralSearch searcher;

     /**

      * Field indicating if the analyzer is enabled.

      */

     private final boolean enabled = checkEnabled();

     /**

      * Determine whether to enable this analyzer or not.

      *

      * @return whether the analyzer should be enabled

      */

     @Override

     public boolean isEnabled() {

         return enabled;

     }

     /**

      * Determines if this analyzer is enabled.

      *

      * @return <code>true</code> if the analyzer is enabled; otherwise

      * <code>false</code>

      */

     private boolean checkEnabled() {

         boolean retval = false;

         try {

             if (Settings.getBoolean(Settings.KEYS.ANALYZER_CENTRAL_ENABLED)) {

                 if (!Settings.getBoolean(Settings.KEYS.ANALYZER_NEXUS_ENABLED)

                         || NexusAnalyzer.DEFAULT_URL.equals(Settings.getString(Settings.KEYS.ANALYZER_NEXUS_URL))) {

                     LOGGER.debug("Enabling the Central analyzer");

                     retval = true;

                 } else {

                     LOGGER.info("Nexus analyzer is enabled, disabling the Central Analyzer");

                 }

             } else {

                 LOGGER.info("Central analyzer disabled");

             }

         } catch (InvalidSettingException ise) {

             LOGGER.warn("Invalid setting. Disabling the Central analyzer");

         }

         return retval;

     }

     /**

      * Initializes the analyzer once before any analysis is performed.

      *

      * @throws InitializationException if there's an error during initialization

      */

     @Override

     public void initializeFileTypeAnalyzer() throws InitializationException {

         LOGGER.debug("Initializing Central analyzer");

         LOGGER.debug("Central analyzer enabled: {}", isEnabled());

         if (isEnabled()) {

             final String searchUrl = Settings.getString(Settings.KEYS.ANALYZER_CENTRAL_URL);

             LOGGER.debug("Central Analyzer URL: {}", searchUrl);

             try {

                 searcher = new CentralSearch(new URL(searchUrl));

             } catch (MalformedURLException ex) {

                 setEnabled(false);

                 throw new InitializationException("The configured URL to Maven Central is malformed: " + searchUrl, ex);

             }

         }

     }

     /**

      * Returns the analyzer's name.

      *

      * @return the name of the analyzer

      */

     @Override

     public String getName() {

         return ANALYZER_NAME;

     }

     /**

      * Returns the key used in the properties file to to reference the

      * analyzer's enabled property.

      *

      * @return the analyzer's enabled property setting key.

      */

     @Override

     protected String getAnalyzerEnabledSettingKey() {

         return Settings.KEYS.ANALYZER_CENTRAL_ENABLED;

     }

     /**

      * Returns the analysis phase under which the analyzer runs.

      *

      * @return the phase under which the analyzer runs

      */

     @Override

     public AnalysisPhase getAnalysisPhase() {

         return ANALYSIS_PHASE;

     }

     /**

      * The file filter used to determine which files this analyzer supports.

      */

     private static final FileFilter FILTER = FileFilterBuilder.newInstance().addExtensions(SUPPORTED_EXTENSIONS).build();

     @Override

     protected FileFilter getFileFilter() {

         return FILTER;

     }

     /**

      * Performs the analysis.

      *

      * @param dependency the dependency to analyze

      * @param engine the engine

      * @throws AnalysisException when there's an exception during analysis

      */

     @Override

     public void analyzeDependency(Dependency dependency, Engine engine) throws AnalysisException {

         if (errorFlag || !isEnabled()) {

             return;

         }

         try {

             final List<MavenArtifact> mas = searcher.searchSha1(dependency.getSha1sum());

             final Confidence confidence = mas.size() > 1 ? Confidence.HIGH : Confidence.HIGHEST;

             for (MavenArtifact ma : mas) {

                 LOGGER.debug("Central analyzer found artifact ({}) for dependency ({})", ma, dependency.getFileName());

                 dependency.addAsEvidence("central", ma, confidence);

                 boolean pomAnalyzed = false;

                 for (Evidence e : dependency.getVendorEvidence()) {

                     if ("pom".equals(e.getSource())) {

                         pomAnalyzed = true;

                         break;

                     }

                 }

                 if (!pomAnalyzed && ma.getPomUrl() != null) {

                     File pomFile = null;

                     try {

                         final File baseDir = Settings.getTempDirectory();

                         pomFile = File.createTempFile("pom", ".xml", baseDir);

                         if (!pomFile.delete()) {

                             LOGGER.warn("Unable to fetch pom.xml for {} from Central; "

                                     + "this could result in undetected CPE/CVEs.", dependency.getFileName());

                             LOGGER.debug("Unable to delete temp file");

                         }

                         LOGGER.debug("Downloading {}", ma.getPomUrl());

                         Downloader.fetchFile(new URL(ma.getPomUrl()), pomFile);

                         PomUtils.analyzePOM(dependency, pomFile);

                     } catch (DownloadFailedException ex) {

                         LOGGER.warn("Unable to download pom.xml for {} from Central; "

                                 + "this could result in undetected CPE/CVEs.", dependency.getFileName());

                     } finally {

                         if (pomFile != null && pomFile.exists() && !FileUtils.deleteQuietly(pomFile)) {

                             LOGGER.debug("Failed to delete temporary pom file {}", pomFile.toString());

                             pomFile.deleteOnExit();

                         }

                     }

                 }

             }

         } catch (IllegalArgumentException iae) {

             LOGGER.info("invalid sha1-hash on {}", dependency.getFileName());

         } catch (FileNotFoundException fnfe) {

             LOGGER.debug("Artifact not found in repository: '{}", dependency.getFileName());

         } catch (IOException ioe) {

             LOGGER.debug("Could not connect to Central search", ioe);

             errorFlag = true;

         }

     }

 }