001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.eclipse.aether.internal.impl.resolution;
020
021import javax.inject.Inject;
022import javax.inject.Named;
023import javax.inject.Singleton;
024
025import java.io.IOException;
026import java.io.UncheckedIOException;
027import java.util.HashSet;
028import java.util.List;
029import java.util.Map;
030import java.util.Objects;
031import java.util.Set;
032
033import org.eclipse.aether.RepositorySystemSession;
034import org.eclipse.aether.artifact.Artifact;
035import org.eclipse.aether.repository.ArtifactRepository;
036import org.eclipse.aether.resolution.ArtifactResult;
037import org.eclipse.aether.spi.checksums.TrustedChecksumsSource;
038import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmFactory;
039import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmFactorySelector;
040import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmHelper;
041import org.eclipse.aether.transfer.ChecksumFailureException;
042import org.eclipse.aether.util.ConfigUtils;
043import org.eclipse.aether.util.artifact.ArtifactIdUtils;
044
045import static java.util.Objects.requireNonNull;
046
047/**
048 * Artifact resolver processor that verifies the checksums of all resolved artifacts against trusted checksums. Is also
049 * able to "record" (calculate and write them) to trusted checksum sources, that do support this operation.
050 * <p>
051 * It uses a list of {@link ChecksumAlgorithmFactory}ies to work with, by default SHA-1.
052 * <p>
053 * Configuration keys:
054 * <ul>
055 *     <li>{@code aether.artifactResolver.postProcessor.trustedChecksums.checksumAlgorithms} - Comma separated
056 *       list of {@link ChecksumAlgorithmFactory} names to use (default "SHA-1").</li>
057 *     <li>{@code aether.artifactResolver.postProcessor.trustedChecksums.failIfMissing} - To fail if artifact
058 *       being validated is missing a trusted checksum (default {@code false}).</li>
059 *     <li>{@code aether.artifactResolver.postProcessor.trustedChecksums.snapshots} - Should snapshot artifacts be
060 *       handled (validated or recorded). Snapshots are by "best practice" in-house produced, hence should be trusted
061 *       (default {@code false}).</li>
062 *     <li>{@code aether.artifactResolver.postProcessor.trustedChecksums.record} - If this value set to {@code true},
063 *       this component with not validate but "record" encountered artifact checksums instead
064 *       (default {@code false}).</li>
065 * </ul>
066 * <p>
067 * This component uses {@link TrustedChecksumsSource} as source of checksums for validation and also to "record" the
068 * calculated checksums. To have this component usable, there must exist at least one enabled checksum source. In case
069 * of multiple checksum sources enabled, ALL of them are used as source for validation or recording. This
070 * implies that if two enabled checksum sources "disagree" about an artifact checksum, the validation failure is
071 * inevitable.
072 *
073 * @since 1.9.0
074 */
075@Singleton
076@Named(TrustedChecksumsArtifactResolverPostProcessor.NAME)
077public final class TrustedChecksumsArtifactResolverPostProcessor extends ArtifactResolverPostProcessorSupport {
078    public static final String NAME = "trustedChecksums";
079
080    private static final String CONFIG_PROPS_PREFIX =
081            ArtifactResolverPostProcessorSupport.CONFIG_PROPS_PREFIX + NAME + ".";
082
083    /**
084     * Is post processor enabled.
085     *
086     * @configurationSource {@link RepositorySystemSession#getConfigProperties()}
087     * @configurationType {@link java.lang.Boolean}
088     * @configurationDefaultValue false
089     */
090    public static final String CONFIG_PROP_ENABLED = ArtifactResolverPostProcessorSupport.CONFIG_PROPS_PREFIX + NAME;
091
092    /**
093     * The checksum algorithms to apply during post-processing as comma separated list.
094     *
095     * @configurationSource {@link RepositorySystemSession#getConfigProperties()}
096     * @configurationType {@link java.lang.String}
097     * @configurationDefaultValue {@link #DEFAULT_CHECKSUM_ALGORITHMS}
098     */
099    public static final String CONFIG_PROP_CHECKSUM_ALGORITHMS = CONFIG_PROPS_PREFIX + "checksumAlgorithms";
100
101    public static final String DEFAULT_CHECKSUM_ALGORITHMS = "SHA-1";
102
103    /**
104     * Should post processor fail resolution if checksum is missing?
105     *
106     * @configurationSource {@link RepositorySystemSession#getConfigProperties()}
107     * @configurationType {@link java.lang.Boolean}
108     * @configurationDefaultValue false
109     */
110    public static final String CONFIG_PROP_FAIL_IF_MISSING = CONFIG_PROPS_PREFIX + "failIfMissing";
111
112    /**
113     * Should post processor process snapshots as well?
114     *
115     * @configurationSource {@link RepositorySystemSession#getConfigProperties()}
116     * @configurationType {@link java.lang.Boolean}
117     * @configurationDefaultValue false
118     */
119    public static final String CONFIG_PROP_SNAPSHOTS = CONFIG_PROPS_PREFIX + "snapshots";
120
121    /**
122     * Should post processor go into "record" mode (and collect checksums instead of validate them)?
123     *
124     * @configurationSource {@link RepositorySystemSession#getConfigProperties()}
125     * @configurationType {@link java.lang.Boolean}
126     * @configurationDefaultValue false
127     */
128    public static final String CONFIG_PROP_RECORD = CONFIG_PROPS_PREFIX + "record";
129
130    private static final String CHECKSUM_ALGORITHMS_CACHE_KEY =
131            TrustedChecksumsArtifactResolverPostProcessor.class.getName() + ".checksumAlgorithms";
132
133    private final ChecksumAlgorithmFactorySelector checksumAlgorithmFactorySelector;
134
135    private final Map<String, TrustedChecksumsSource> trustedChecksumsSources;
136
137    @Inject
138    public TrustedChecksumsArtifactResolverPostProcessor(
139            ChecksumAlgorithmFactorySelector checksumAlgorithmFactorySelector,
140            Map<String, TrustedChecksumsSource> trustedChecksumsSources) {
141        this.checksumAlgorithmFactorySelector = requireNonNull(checksumAlgorithmFactorySelector);
142        this.trustedChecksumsSources = requireNonNull(trustedChecksumsSources);
143    }
144
145    @Override
146    protected boolean isEnabled(RepositorySystemSession session) {
147        return ConfigUtils.getBoolean(session, false, CONFIG_PROP_ENABLED);
148    }
149
150    @SuppressWarnings("unchecked")
151    @Override
152    protected void doPostProcess(RepositorySystemSession session, List<ArtifactResult> artifactResults) {
153        final List<ChecksumAlgorithmFactory> checksumAlgorithms = (List<ChecksumAlgorithmFactory>) session.getData()
154                .computeIfAbsent(
155                        CHECKSUM_ALGORITHMS_CACHE_KEY,
156                        () -> checksumAlgorithmFactorySelector.selectList(
157                                ConfigUtils.parseCommaSeparatedUniqueNames(ConfigUtils.getString(
158                                        session, DEFAULT_CHECKSUM_ALGORITHMS, CONFIG_PROP_CHECKSUM_ALGORITHMS))));
159
160        final boolean failIfMissing = ConfigUtils.getBoolean(session, false, CONFIG_PROP_FAIL_IF_MISSING);
161        final boolean record = ConfigUtils.getBoolean(session, false, CONFIG_PROP_RECORD);
162        final boolean snapshots = ConfigUtils.getBoolean(session, false, CONFIG_PROP_SNAPSHOTS);
163
164        for (ArtifactResult artifactResult : artifactResults) {
165            if (artifactResult.getArtifact().isSnapshot() && !snapshots) {
166                continue;
167            }
168            if (artifactResult.isResolved()) {
169                if (record) {
170                    recordArtifactChecksums(session, artifactResult, checksumAlgorithms);
171                } else if (!validateArtifactChecksums(session, artifactResult, checksumAlgorithms, failIfMissing)) {
172                    artifactResult.setArtifact(artifactResult.getArtifact().setFile(null)); // make it unresolved
173                }
174            }
175        }
176    }
177
178    /**
179     * Calculates and records checksums into trusted sources that support writing.
180     */
181    private void recordArtifactChecksums(
182            RepositorySystemSession session,
183            ArtifactResult artifactResult,
184            List<ChecksumAlgorithmFactory> checksumAlgorithmFactories) {
185        Artifact artifact = artifactResult.getArtifact();
186        ArtifactRepository artifactRepository = artifactResult.getRepository();
187        try {
188            final Map<String, String> calculatedChecksums =
189                    ChecksumAlgorithmHelper.calculate(artifact.getFile(), checksumAlgorithmFactories);
190
191            for (TrustedChecksumsSource trustedChecksumsSource : trustedChecksumsSources.values()) {
192                TrustedChecksumsSource.Writer writer =
193                        trustedChecksumsSource.getTrustedArtifactChecksumsWriter(session);
194                if (writer != null) {
195                    try {
196                        writer.addTrustedArtifactChecksums(
197                                artifact, artifactRepository, checksumAlgorithmFactories, calculatedChecksums);
198                    } catch (IOException e) {
199                        throw new UncheckedIOException(
200                                "Could not write required checksums for " + artifact.getFile(), e);
201                    }
202                }
203            }
204        } catch (IOException e) {
205            throw new UncheckedIOException("Could not calculate required checksums for " + artifact.getFile(), e);
206        }
207    }
208
209    /**
210     * Validates trusted checksums against {@link ArtifactResult}, returns {@code true} denoting "valid" checksums or
211     * {@code false} denoting "invalid" checksums.
212     */
213    private boolean validateArtifactChecksums(
214            RepositorySystemSession session,
215            ArtifactResult artifactResult,
216            List<ChecksumAlgorithmFactory> checksumAlgorithmFactories,
217            boolean failIfMissing) {
218        Artifact artifact = artifactResult.getArtifact();
219        ArtifactRepository artifactRepository = artifactResult.getRepository();
220        boolean valid = true;
221        boolean validated = false;
222        try {
223            // full set: calculate all algorithms we were asked for
224            final Map<String, String> calculatedChecksums =
225                    ChecksumAlgorithmHelper.calculate(artifact.getFile(), checksumAlgorithmFactories);
226
227            for (Map.Entry<String, TrustedChecksumsSource> entry : trustedChecksumsSources.entrySet()) {
228                final String trustedSourceName = entry.getKey();
229                final TrustedChecksumsSource trustedChecksumsSource = entry.getValue();
230
231                // upper bound set: ask source for checksums, ideally same as calculatedChecksums but may be less
232                Map<String, String> trustedChecksums = trustedChecksumsSource.getTrustedArtifactChecksums(
233                        session, artifact, artifactRepository, checksumAlgorithmFactories);
234
235                if (trustedChecksums == null) {
236                    continue; // not enabled
237                }
238                validated = true;
239
240                if (!calculatedChecksums.equals(trustedChecksums)) {
241                    Set<String> missingTrustedAlg = new HashSet<>(calculatedChecksums.keySet());
242                    missingTrustedAlg.removeAll(trustedChecksums.keySet());
243
244                    if (!missingTrustedAlg.isEmpty() && failIfMissing) {
245                        artifactResult.addException(new ChecksumFailureException("Missing from " + trustedSourceName
246                                + " trusted checksum(s) " + missingTrustedAlg + " for artifact "
247                                + ArtifactIdUtils.toId(artifact)));
248                        valid = false;
249                    }
250
251                    // compare values but only present ones, failIfMissing handled above
252                    // we still want to report all: algX - missing, algY - mismatch, etc
253                    for (ChecksumAlgorithmFactory checksumAlgorithmFactory : checksumAlgorithmFactories) {
254                        String calculatedChecksum = calculatedChecksums.get(checksumAlgorithmFactory.getName());
255                        String trustedChecksum = trustedChecksums.get(checksumAlgorithmFactory.getName());
256                        if (trustedChecksum != null && !Objects.equals(calculatedChecksum, trustedChecksum)) {
257                            artifactResult.addException(new ChecksumFailureException("Artifact "
258                                    + ArtifactIdUtils.toId(artifact) + " trusted checksum mismatch: "
259                                    + trustedSourceName + "=" + trustedChecksum + "; calculated="
260                                    + calculatedChecksum));
261                            valid = false;
262                        }
263                    }
264                }
265            }
266
267            if (!validated && failIfMissing) {
268                artifactResult.addException(new ChecksumFailureException(
269                        "There are no enabled trusted checksums" + " source(s) to validate against."));
270                valid = false;
271            }
272        } catch (IOException e) {
273            throw new UncheckedIOException(e);
274        }
275        return valid;
276    }
277}