src/test/java/com/android/tools/build/apkzlib/sign/JarSigningTest.java - platform/tools/apkzlib - Git at Google

 /*
  * Copyright (C) 2016 The Android Open Source Project
  *
  * 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.android.tools.build.apkzlib.sign;

 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNotNull;

 import com.android.tools.build.apkzlib.utils.ApkZFileTestUtils;
 import com.android.tools.build.apkzlib.utils.ApkZLibPair;
 import com.android.tools.build.apkzlib.zip.StoredEntry;
 import com.android.tools.build.apkzlib.zip.ZFile;
 import com.google.common.base.Charsets;
 import com.google.common.hash.Hashing;
 import java.io.ByteArrayInputStream;
 import java.io.File;
 import java.io.InputStream;
 import java.security.PrivateKey;
 import java.security.cert.X509Certificate;
 import java.util.Base64;
 import java.util.jar.Attributes;
 import java.util.jar.Manifest;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;

 public class JarSigningTest {

     @Rule
     public TemporaryFolder mTemporaryFolder = new TemporaryFolder();

     @Test
     public void signEmptyJar() throws Exception {
         File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");

         try (ZFile zf = new ZFile(zipFile)) {
             ApkZFileTestUtils.addAndroidManifest(zf);
             ManifestGenerationExtension manifestExtension =
                     new ManifestGenerationExtension("Me", "Me");
             manifestExtension.register(zf);

             ApkZLibPair<PrivateKey, X509Certificate> p =
                     SignatureTestUtils.generateSignaturePre18();

             new SigningExtension(12, p.v2, p.v1, true, false).register(zf);
         }

         try (ZFile verifyZFile = new ZFile(zipFile)) {
             StoredEntry manifestEntry = verifyZFile.get("META-INF/MANIFEST.MF");
             assertNotNull(manifestEntry);

             Manifest manifest = new Manifest(new ByteArrayInputStream(manifestEntry.read()));
             assertEquals(3, manifest.getMainAttributes().size());
             assertEquals("1.0", manifest.getMainAttributes().getValue("Manifest-Version"));
             assertEquals("Me", manifest.getMainAttributes().getValue("Created-By"));
             assertEquals("Me", manifest.getMainAttributes().getValue("Built-By"));
         }
     }

     @Test
     public void signJarWithPrexistingSimpleTextFilePre18() throws Exception {
         File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");
         ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePre18();

         try (ZFile zf1 = new ZFile(zipFile)) {
             ApkZFileTestUtils.addAndroidManifest(zf1);
             zf1.add("directory/file",
                     new ByteArrayInputStream("useless text".getBytes(Charsets.US_ASCII)));
         }

         try (ZFile zf2 = new ZFile(zipFile)) {
             ManifestGenerationExtension me = new ManifestGenerationExtension("Merry", "Christmas");
             me.register(zf2);
             new SigningExtension(10, p.v2, p.v1, true, false).register(zf2);
         }

         try (ZFile zf3 = new ZFile(zipFile)) {
             StoredEntry manifestEntry = zf3.get("META-INF/MANIFEST.MF");
             assertNotNull(manifestEntry);

             Manifest manifest = new Manifest(new ByteArrayInputStream(manifestEntry.read()));
             assertEquals(3, manifest.getMainAttributes().size());
             assertEquals("1.0", manifest.getMainAttributes().getValue("Manifest-Version"));
             assertEquals("Merry", manifest.getMainAttributes().getValue("Built-By"));
             assertEquals("Christmas", manifest.getMainAttributes().getValue("Created-By"));

             Attributes attrs = manifest.getAttributes("directory/file");
             assertNotNull(attrs);
             assertEquals(1, attrs.size());
             assertEquals("OOQgIEXBissIvva3ydRoaXk29Rk=", attrs.getValue("SHA1-Digest"));

             StoredEntry signatureEntry = zf3.get("META-INF/CERT.SF");
             assertNotNull(signatureEntry);

             Manifest signature = new Manifest(new ByteArrayInputStream(signatureEntry.read()));
             assertEquals(3, signature.getMainAttributes().size());
             assertEquals("1.0", signature.getMainAttributes().getValue("Signature-Version"));
             assertEquals("1.0 (Android)", signature.getMainAttributes().getValue("Created-By"));

             byte[] manifestTextBytes = manifestEntry.read();
             byte[] manifestSha1Bytes = Hashing.sha1().hashBytes(manifestTextBytes).asBytes();
             String manifestSha1 = Base64.getEncoder().encodeToString(manifestSha1Bytes);

             assertEquals(manifestSha1,
                     signature.getMainAttributes().getValue("SHA1-Digest-Manifest"));

             Attributes signAttrs = signature.getAttributes("directory/file");
             assertNotNull(signAttrs);
             assertEquals(1, signAttrs.size());
             assertEquals("LGSOwy4uGcUWoc+ZhS8ukzmf0fY=", signAttrs.getValue("SHA1-Digest"));

             StoredEntry rsaEntry = zf3.get("META-INF/CERT.RSA");
             assertNotNull(rsaEntry);
         }
     }

     @Test
     public void signJarWithPrexistingSimpleTextFilePos18() throws Exception {
         File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");
         try (ZFile zf1 = new ZFile(zipFile)) {
             ApkZFileTestUtils.addAndroidManifest(zf1);
             zf1.add("directory/file", new ByteArrayInputStream("useless text".getBytes(
                     Charsets.US_ASCII)));
         }

         ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePos18();

         try (ZFile zf2 = new ZFile(zipFile)) {
             ManifestGenerationExtension me = new ManifestGenerationExtension("Merry", "Christmas");
             me.register(zf2);
             new SigningExtension(21, p.v2, p.v1, true, false).register(zf2);
         }

         try (ZFile zf3 = new ZFile(zipFile)) {
             StoredEntry manifestEntry = zf3.get("META-INF/MANIFEST.MF");
             assertNotNull(manifestEntry);

             Manifest manifest = new Manifest(new ByteArrayInputStream(manifestEntry.read()));
             assertEquals(3, manifest.getMainAttributes().size());
             assertEquals("1.0", manifest.getMainAttributes().getValue("Manifest-Version"));
             assertEquals("Merry", manifest.getMainAttributes().getValue("Built-By"));
             assertEquals("Christmas", manifest.getMainAttributes().getValue("Created-By"));

             Attributes attrs = manifest.getAttributes("directory/file");
             assertNotNull(attrs);
             assertEquals(1, attrs.size());
             assertEquals("QjupZsopQM/01O6+sWHqH64ilMmoBEtljg9VEqN6aI4=",
                     attrs.getValue("SHA-256-Digest"));

             StoredEntry signatureEntry = zf3.get("META-INF/CERT.SF");
             assertNotNull(signatureEntry);

             Manifest signature = new Manifest(new ByteArrayInputStream(signatureEntry.read()));
             assertEquals(3, signature.getMainAttributes().size());
             assertEquals("1.0", signature.getMainAttributes().getValue("Signature-Version"));
             assertEquals("1.0 (Android)", signature.getMainAttributes().getValue("Created-By"));

             byte[] manifestTextBytes = manifestEntry.read();
             byte[] manifestSha256Bytes = Hashing.sha256().hashBytes(manifestTextBytes).asBytes();
             String manifestSha256 = Base64.getEncoder().encodeToString(manifestSha256Bytes);

             assertEquals(manifestSha256, signature.getMainAttributes().getValue(
                     "SHA-256-Digest-Manifest"));

             Attributes signAttrs = signature.getAttributes("directory/file");
             assertNotNull(signAttrs);
             assertEquals(1, signAttrs.size());
             assertEquals("dBnaLpqNjmUnLlZF4tNqOcDWL8wy8Tsw1ZYFqTZhjIs=",
                     signAttrs.getValue("SHA-256-Digest"));

             StoredEntry ecdsaEntry = zf3.get("META-INF/CERT.EC");
             assertNotNull(ecdsaEntry);
         }
     }

     @Test
     public void v2SignAddsApkSigningBlock() throws Exception {
         File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");
         try (ZFile zf = new ZFile(zipFile)) {
             ApkZFileTestUtils.addAndroidManifest(zf);
             ManifestGenerationExtension manifestExtension =
                     new ManifestGenerationExtension("Me", "Me");
             manifestExtension.register(zf);

             ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePre18();

             new SigningExtension(12, p.v2, p.v1, false, true).register(zf);
         }

         try (ZFile verifyZFile = new ZFile(zipFile)) {
             long centralDirOffset = verifyZFile.getCentralDirectoryOffset();
             byte[] apkSigningBlockMagic = new byte[16];
             verifyZFile.directFullyRead(
                     centralDirOffset - apkSigningBlockMagic.length, apkSigningBlockMagic);
             assertEquals("APK Sig Block 42", new String(apkSigningBlockMagic, "US-ASCII"));
         }
     }

     @Test
     public void v1ReSignOnFileChange() throws Exception {
         File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");
         ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePos18();

         byte[] file1Contents = "I am a test file".getBytes(Charsets.US_ASCII);
         String file1Name = "path/to/file1";
         byte[] file1Sha = Hashing.sha256().hashBytes(file1Contents).asBytes();
         String file1ShaTxt = Base64.getEncoder().encodeToString(file1Sha);

         String builtBy = "Santa Claus";
         String createdBy = "Uses Android";

         try (ZFile zf1 = new ZFile(zipFile)) {
             ApkZFileTestUtils.addAndroidManifest(zf1);
             zf1.add(file1Name, new ByteArrayInputStream(file1Contents));
             ManifestGenerationExtension me = new ManifestGenerationExtension(builtBy, createdBy);
             me.register(zf1);
             new SigningExtension(21, p.v2, p.v1, true, false).register(zf1);

             zf1.update();

             StoredEntry manifestEntry = zf1.get("META-INF/MANIFEST.MF");
             assertNotNull(manifestEntry);

             try (InputStream manifestIs = manifestEntry.open()) {
                 Manifest manifest = new Manifest(manifestIs);

                 assertEquals(2, manifest.getEntries().size());

                 Attributes file1Attrs = manifest.getEntries().get(file1Name);
                 assertNotNull(file1Attrs);
                 assertEquals(file1ShaTxt, file1Attrs.getValue("SHA-256-Digest"));
             }

             /*
              * Change the file without closing the zip.
              */
             file1Contents = "I am a modified test file".getBytes(Charsets.US_ASCII);
             file1Sha = Hashing.sha256().hashBytes(file1Contents).asBytes();
             file1ShaTxt = Base64.getEncoder().encodeToString(file1Sha);

             zf1.add(file1Name, new ByteArrayInputStream(file1Contents));

             zf1.update();

             manifestEntry = zf1.get("META-INF/MANIFEST.MF");
             assertNotNull(manifestEntry);

             try (InputStream manifestIs = manifestEntry.open()) {
                 Manifest manifest = new Manifest(manifestIs);

                 assertEquals(2, manifest.getEntries().size());

                 Attributes file1Attrs = manifest.getEntries().get(file1Name);
                 assertNotNull(file1Attrs);
                 assertEquals(file1ShaTxt, file1Attrs.getValue("SHA-256-Digest"));
             }
         }

         /*
          * Change the file closing the zip.
          */
         file1Contents = "I have changed again!".getBytes(Charsets.US_ASCII);
         file1Sha = Hashing.sha256().hashBytes(file1Contents).asBytes();
         file1ShaTxt = Base64.getEncoder().encodeToString(file1Sha);

         try (ZFile zf2 = new ZFile(zipFile)) {
             ApkZFileTestUtils.addAndroidManifest(zf2);
             ManifestGenerationExtension me = new ManifestGenerationExtension(builtBy, createdBy);
             me.register(zf2);
             new SigningExtension(21, p.v2, p.v1, true, false).register(zf2);

             zf2.add(file1Name, new ByteArrayInputStream(file1Contents));

             zf2.update();

             StoredEntry manifestEntry = zf2.get("META-INF/MANIFEST.MF");
             assertNotNull(manifestEntry);

             try (InputStream manifestIs = manifestEntry.open()) {
                 Manifest manifest = new Manifest(manifestIs);

                 assertEquals(2, manifest.getEntries().size());

                 Attributes file1Attrs = manifest.getEntries().get(file1Name);
                 assertNotNull(file1Attrs);
                 assertEquals(file1ShaTxt, file1Attrs.getValue("SHA-256-Digest"));
             }
         }
     }

     @Test
     public void openSignedJarDoesNotForcesWriteIfSignatureIsNotCorrect() throws Exception {
         File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");

         ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePos18();

         String fileName = "file";
         byte[] fileContents = "Very interesting contents".getBytes(Charsets.US_ASCII);

         try (ZFile zf = new ZFile(zipFile)) {
             ApkZFileTestUtils.addAndroidManifest(zf);
             ManifestGenerationExtension me = new ManifestGenerationExtension("I", "Android");
             me.register(zf);
             new SigningExtension(21, p.v2, p.v1, true, false).register(zf);

             zf.add(fileName, new ByteArrayInputStream(fileContents));
         }

         long fileTimestamp = zipFile.lastModified();

         ApkZFileTestUtils.waitForFileSystemTick(fileTimestamp);

         /*
          * Open the zip file, but don't touch it.
          */
         try (ZFile zf = new ZFile(zipFile)) {
             ManifestGenerationExtension me = new ManifestGenerationExtension("I", "Android");
             me.register(zf);
             new SigningExtension(21, p.v2, p.v1, true, false).register(zf);
         }

         /*
          * Check the file wasn't touched.
          */
         assertEquals(fileTimestamp, zipFile.lastModified());

         /*
          * Change the file contents ignoring any signing.
          */
         fileContents = "Not so interesting contents".getBytes(Charsets.US_ASCII);
         try (ZFile zf = new ZFile(zipFile)) {
             zf.add(fileName, new ByteArrayInputStream(fileContents));
         }

         fileTimestamp = zipFile.lastModified();

         /*
          * Wait to make sure the timestamp can increase.
          */
         while (true) {
             File notUsed = mTemporaryFolder.newFile();
             long notTimestamp = notUsed.lastModified();
             notUsed.delete();
             if (notTimestamp > fileTimestamp) {
                 break;
             }
         }

         /*
          * Open the zip file, but do any changes. The need to updating the signature should force
          * a file update.
          */
         try (ZFile zf = new ZFile(zipFile)) {
             ManifestGenerationExtension me = new ManifestGenerationExtension("I", "Android");
             me.register(zf);
             new SigningExtension(21, p.v2, p.v1, true, false).register(zf);
         }

         /*
          * Check the file was touched.
          */
         assertNotEquals(fileTimestamp, zipFile.lastModified());
     }
 }
	/*
	* Copyright (C) 2016 The Android Open Source Project
	*
	* 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.android.tools.build.apkzlib.sign;

	import static org.junit.Assert.assertEquals;
	import static org.junit.Assert.assertNotEquals;
	import static org.junit.Assert.assertNotNull;

	import com.android.tools.build.apkzlib.utils.ApkZFileTestUtils;
	import com.android.tools.build.apkzlib.utils.ApkZLibPair;
	import com.android.tools.build.apkzlib.zip.StoredEntry;
	import com.android.tools.build.apkzlib.zip.ZFile;
	import com.google.common.base.Charsets;
	import com.google.common.hash.Hashing;
	import java.io.ByteArrayInputStream;
	import java.io.File;
	import java.io.InputStream;
	import java.security.PrivateKey;
	import java.security.cert.X509Certificate;
	import java.util.Base64;
	import java.util.jar.Attributes;
	import java.util.jar.Manifest;
	import org.junit.Rule;
	import org.junit.Test;
	import org.junit.rules.TemporaryFolder;

	public class JarSigningTest {

	@Rule
	public TemporaryFolder mTemporaryFolder = new TemporaryFolder();

	@Test
	public void signEmptyJar() throws Exception {
	File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");

	try (ZFile zf = new ZFile(zipFile)) {
	ApkZFileTestUtils.addAndroidManifest(zf);
	ManifestGenerationExtension manifestExtension =
	new ManifestGenerationExtension("Me", "Me");
	manifestExtension.register(zf);

	ApkZLibPair<PrivateKey, X509Certificate> p =
	SignatureTestUtils.generateSignaturePre18();

	new SigningExtension(12, p.v2, p.v1, true, false).register(zf);
	}

	try (ZFile verifyZFile = new ZFile(zipFile)) {
	StoredEntry manifestEntry = verifyZFile.get("META-INF/MANIFEST.MF");
	assertNotNull(manifestEntry);

	Manifest manifest = new Manifest(new ByteArrayInputStream(manifestEntry.read()));
	assertEquals(3, manifest.getMainAttributes().size());
	assertEquals("1.0", manifest.getMainAttributes().getValue("Manifest-Version"));
	assertEquals("Me", manifest.getMainAttributes().getValue("Created-By"));
	assertEquals("Me", manifest.getMainAttributes().getValue("Built-By"));
	}
	}

	@Test
	public void signJarWithPrexistingSimpleTextFilePre18() throws Exception {
	File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");
	ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePre18();

	try (ZFile zf1 = new ZFile(zipFile)) {
	ApkZFileTestUtils.addAndroidManifest(zf1);
	zf1.add("directory/file",
	new ByteArrayInputStream("useless text".getBytes(Charsets.US_ASCII)));
	}

	try (ZFile zf2 = new ZFile(zipFile)) {
	ManifestGenerationExtension me = new ManifestGenerationExtension("Merry", "Christmas");
	me.register(zf2);
	new SigningExtension(10, p.v2, p.v1, true, false).register(zf2);
	}

	try (ZFile zf3 = new ZFile(zipFile)) {
	StoredEntry manifestEntry = zf3.get("META-INF/MANIFEST.MF");
	assertNotNull(manifestEntry);

	Manifest manifest = new Manifest(new ByteArrayInputStream(manifestEntry.read()));
	assertEquals(3, manifest.getMainAttributes().size());
	assertEquals("1.0", manifest.getMainAttributes().getValue("Manifest-Version"));
	assertEquals("Merry", manifest.getMainAttributes().getValue("Built-By"));
	assertEquals("Christmas", manifest.getMainAttributes().getValue("Created-By"));

	Attributes attrs = manifest.getAttributes("directory/file");
	assertNotNull(attrs);
	assertEquals(1, attrs.size());
	assertEquals("OOQgIEXBissIvva3ydRoaXk29Rk=", attrs.getValue("SHA1-Digest"));

	StoredEntry signatureEntry = zf3.get("META-INF/CERT.SF");
	assertNotNull(signatureEntry);

	Manifest signature = new Manifest(new ByteArrayInputStream(signatureEntry.read()));
	assertEquals(3, signature.getMainAttributes().size());
	assertEquals("1.0", signature.getMainAttributes().getValue("Signature-Version"));
	assertEquals("1.0 (Android)", signature.getMainAttributes().getValue("Created-By"));

	byte[] manifestTextBytes = manifestEntry.read();
	byte[] manifestSha1Bytes = Hashing.sha1().hashBytes(manifestTextBytes).asBytes();
	String manifestSha1 = Base64.getEncoder().encodeToString(manifestSha1Bytes);

	assertEquals(manifestSha1,
	signature.getMainAttributes().getValue("SHA1-Digest-Manifest"));

	Attributes signAttrs = signature.getAttributes("directory/file");
	assertNotNull(signAttrs);
	assertEquals(1, signAttrs.size());
	assertEquals("LGSOwy4uGcUWoc+ZhS8ukzmf0fY=", signAttrs.getValue("SHA1-Digest"));

	StoredEntry rsaEntry = zf3.get("META-INF/CERT.RSA");
	assertNotNull(rsaEntry);
	}
	}

	@Test
	public void signJarWithPrexistingSimpleTextFilePos18() throws Exception {
	File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");
	try (ZFile zf1 = new ZFile(zipFile)) {
	ApkZFileTestUtils.addAndroidManifest(zf1);
	zf1.add("directory/file", new ByteArrayInputStream("useless text".getBytes(
	Charsets.US_ASCII)));
	}

	ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePos18();

	try (ZFile zf2 = new ZFile(zipFile)) {
	ManifestGenerationExtension me = new ManifestGenerationExtension("Merry", "Christmas");
	me.register(zf2);
	new SigningExtension(21, p.v2, p.v1, true, false).register(zf2);
	}

	try (ZFile zf3 = new ZFile(zipFile)) {
	StoredEntry manifestEntry = zf3.get("META-INF/MANIFEST.MF");
	assertNotNull(manifestEntry);

	Manifest manifest = new Manifest(new ByteArrayInputStream(manifestEntry.read()));
	assertEquals(3, manifest.getMainAttributes().size());
	assertEquals("1.0", manifest.getMainAttributes().getValue("Manifest-Version"));
	assertEquals("Merry", manifest.getMainAttributes().getValue("Built-By"));
	assertEquals("Christmas", manifest.getMainAttributes().getValue("Created-By"));

	Attributes attrs = manifest.getAttributes("directory/file");
	assertNotNull(attrs);
	assertEquals(1, attrs.size());
	assertEquals("QjupZsopQM/01O6+sWHqH64ilMmoBEtljg9VEqN6aI4=",
	attrs.getValue("SHA-256-Digest"));

	StoredEntry signatureEntry = zf3.get("META-INF/CERT.SF");
	assertNotNull(signatureEntry);

	Manifest signature = new Manifest(new ByteArrayInputStream(signatureEntry.read()));
	assertEquals(3, signature.getMainAttributes().size());
	assertEquals("1.0", signature.getMainAttributes().getValue("Signature-Version"));
	assertEquals("1.0 (Android)", signature.getMainAttributes().getValue("Created-By"));

	byte[] manifestTextBytes = manifestEntry.read();
	byte[] manifestSha256Bytes = Hashing.sha256().hashBytes(manifestTextBytes).asBytes();
	String manifestSha256 = Base64.getEncoder().encodeToString(manifestSha256Bytes);

	assertEquals(manifestSha256, signature.getMainAttributes().getValue(
	"SHA-256-Digest-Manifest"));

	Attributes signAttrs = signature.getAttributes("directory/file");
	assertNotNull(signAttrs);
	assertEquals(1, signAttrs.size());
	assertEquals("dBnaLpqNjmUnLlZF4tNqOcDWL8wy8Tsw1ZYFqTZhjIs=",
	signAttrs.getValue("SHA-256-Digest"));

	StoredEntry ecdsaEntry = zf3.get("META-INF/CERT.EC");
	assertNotNull(ecdsaEntry);
	}
	}

	@Test
	public void v2SignAddsApkSigningBlock() throws Exception {
	File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");
	try (ZFile zf = new ZFile(zipFile)) {
	ApkZFileTestUtils.addAndroidManifest(zf);
	ManifestGenerationExtension manifestExtension =
	new ManifestGenerationExtension("Me", "Me");
	manifestExtension.register(zf);

	ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePre18();

	new SigningExtension(12, p.v2, p.v1, false, true).register(zf);
	}

	try (ZFile verifyZFile = new ZFile(zipFile)) {
	long centralDirOffset = verifyZFile.getCentralDirectoryOffset();
	byte[] apkSigningBlockMagic = new byte[16];
	verifyZFile.directFullyRead(
	centralDirOffset - apkSigningBlockMagic.length, apkSigningBlockMagic);
	assertEquals("APK Sig Block 42", new String(apkSigningBlockMagic, "US-ASCII"));
	}
	}

	@Test
	public void v1ReSignOnFileChange() throws Exception {
	File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");
	ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePos18();

	byte[] file1Contents = "I am a test file".getBytes(Charsets.US_ASCII);
	String file1Name = "path/to/file1";
	byte[] file1Sha = Hashing.sha256().hashBytes(file1Contents).asBytes();
	String file1ShaTxt = Base64.getEncoder().encodeToString(file1Sha);

	String builtBy = "Santa Claus";
	String createdBy = "Uses Android";

	try (ZFile zf1 = new ZFile(zipFile)) {
	ApkZFileTestUtils.addAndroidManifest(zf1);
	zf1.add(file1Name, new ByteArrayInputStream(file1Contents));
	ManifestGenerationExtension me = new ManifestGenerationExtension(builtBy, createdBy);
	me.register(zf1);
	new SigningExtension(21, p.v2, p.v1, true, false).register(zf1);

	zf1.update();

	StoredEntry manifestEntry = zf1.get("META-INF/MANIFEST.MF");
	assertNotNull(manifestEntry);

	try (InputStream manifestIs = manifestEntry.open()) {
	Manifest manifest = new Manifest(manifestIs);

	assertEquals(2, manifest.getEntries().size());

	Attributes file1Attrs = manifest.getEntries().get(file1Name);
	assertNotNull(file1Attrs);
	assertEquals(file1ShaTxt, file1Attrs.getValue("SHA-256-Digest"));
	}

	/*
	* Change the file without closing the zip.
	*/
	file1Contents = "I am a modified test file".getBytes(Charsets.US_ASCII);
	file1Sha = Hashing.sha256().hashBytes(file1Contents).asBytes();
	file1ShaTxt = Base64.getEncoder().encodeToString(file1Sha);

	zf1.add(file1Name, new ByteArrayInputStream(file1Contents));

	zf1.update();

	manifestEntry = zf1.get("META-INF/MANIFEST.MF");
	assertNotNull(manifestEntry);

	try (InputStream manifestIs = manifestEntry.open()) {
	Manifest manifest = new Manifest(manifestIs);

	assertEquals(2, manifest.getEntries().size());

	Attributes file1Attrs = manifest.getEntries().get(file1Name);
	assertNotNull(file1Attrs);
	assertEquals(file1ShaTxt, file1Attrs.getValue("SHA-256-Digest"));
	}
	}

	/*
	* Change the file closing the zip.
	*/
	file1Contents = "I have changed again!".getBytes(Charsets.US_ASCII);
	file1Sha = Hashing.sha256().hashBytes(file1Contents).asBytes();
	file1ShaTxt = Base64.getEncoder().encodeToString(file1Sha);

	try (ZFile zf2 = new ZFile(zipFile)) {
	ApkZFileTestUtils.addAndroidManifest(zf2);
	ManifestGenerationExtension me = new ManifestGenerationExtension(builtBy, createdBy);
	me.register(zf2);
	new SigningExtension(21, p.v2, p.v1, true, false).register(zf2);

	zf2.add(file1Name, new ByteArrayInputStream(file1Contents));

	zf2.update();

	StoredEntry manifestEntry = zf2.get("META-INF/MANIFEST.MF");
	assertNotNull(manifestEntry);

	try (InputStream manifestIs = manifestEntry.open()) {
	Manifest manifest = new Manifest(manifestIs);

	assertEquals(2, manifest.getEntries().size());

	Attributes file1Attrs = manifest.getEntries().get(file1Name);
	assertNotNull(file1Attrs);
	assertEquals(file1ShaTxt, file1Attrs.getValue("SHA-256-Digest"));
	}
	}
	}

	@Test
	public void openSignedJarDoesNotForcesWriteIfSignatureIsNotCorrect() throws Exception {
	File zipFile = new File(mTemporaryFolder.getRoot(), "a.zip");

	ApkZLibPair<PrivateKey, X509Certificate> p = SignatureTestUtils.generateSignaturePos18();

	String fileName = "file";
	byte[] fileContents = "Very interesting contents".getBytes(Charsets.US_ASCII);

	try (ZFile zf = new ZFile(zipFile)) {
	ApkZFileTestUtils.addAndroidManifest(zf);
	ManifestGenerationExtension me = new ManifestGenerationExtension("I", "Android");
	me.register(zf);
	new SigningExtension(21, p.v2, p.v1, true, false).register(zf);

	zf.add(fileName, new ByteArrayInputStream(fileContents));
	}

	long fileTimestamp = zipFile.lastModified();

	ApkZFileTestUtils.waitForFileSystemTick(fileTimestamp);

	/*
	* Open the zip file, but don't touch it.
	*/
	try (ZFile zf = new ZFile(zipFile)) {
	ManifestGenerationExtension me = new ManifestGenerationExtension("I", "Android");
	me.register(zf);
	new SigningExtension(21, p.v2, p.v1, true, false).register(zf);
	}

	/*
	* Check the file wasn't touched.
	*/
	assertEquals(fileTimestamp, zipFile.lastModified());

	/*
	* Change the file contents ignoring any signing.
	*/
	fileContents = "Not so interesting contents".getBytes(Charsets.US_ASCII);
	try (ZFile zf = new ZFile(zipFile)) {
	zf.add(fileName, new ByteArrayInputStream(fileContents));
	}

	fileTimestamp = zipFile.lastModified();

	/*
	* Wait to make sure the timestamp can increase.
	*/
	while (true) {
	File notUsed = mTemporaryFolder.newFile();
	long notTimestamp = notUsed.lastModified();
	notUsed.delete();
	if (notTimestamp > fileTimestamp) {
	break;
	}
	}

	/*
	* Open the zip file, but do any changes. The need to updating the signature should force
	* a file update.
	*/
	try (ZFile zf = new ZFile(zipFile)) {
	ManifestGenerationExtension me = new ManifestGenerationExtension("I", "Android");
	me.register(zf);
	new SigningExtension(21, p.v2, p.v1, true, false).register(zf);
	}

	/*
	* Check the file was touched.
	*/
	assertNotEquals(fileTimestamp, zipFile.lastModified());
	}
	}