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Diffstat (limited to 'org.eclipse.jgit.test/tst/org/eclipse/jgit/util/sha1/SHA1Test.java')
-rw-r--r--org.eclipse.jgit.test/tst/org/eclipse/jgit/util/sha1/SHA1Test.java238
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diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/sha1/SHA1Test.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/sha1/SHA1Test.java
new file mode 100644
index 0000000000..07789898a4
--- /dev/null
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/sha1/SHA1Test.java
@@ -0,0 +1,238 @@
+/*
+ * Copyright (C) 2017, Google Inc.
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials provided
+ * with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ * names of its contributors may be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.eclipse.jgit.util.sha1;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.junit.Assume.assumeTrue;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.util.IO;
+import org.junit.Test;
+
+public class SHA1Test {
+ private static final String TEST1 = "abc";
+
+ private static final String TEST2a = "abcdbcdecdefdefgefghfghighijhi";
+ private static final String TEST2b = "jkijkljklmklmnlmnomnopnopq";
+ private static final String TEST2 = TEST2a + TEST2b;
+
+ @Test
+ public void test0() throws NoSuchAlgorithmException {
+ ObjectId exp = ObjectId
+ .fromString("da39a3ee5e6b4b0d3255bfef95601890afd80709");
+
+ MessageDigest m = MessageDigest.getInstance("SHA-1");
+ m.update(new byte[] {});
+ ObjectId m1 = ObjectId.fromRaw(m.digest());
+
+ SHA1 s = SHA1.newInstance();
+ s.update(new byte[] {});
+ ObjectId s1 = ObjectId.fromRaw(s.digest());
+
+ s.reset();
+ s.update(new byte[] {});
+ ObjectId s2 = s.toObjectId();
+
+ assertEquals(m1, s1);
+ assertEquals(exp, s1);
+ assertEquals(exp, s2);
+ }
+
+ @Test
+ public void test1() throws NoSuchAlgorithmException {
+ ObjectId exp = ObjectId
+ .fromString("a9993e364706816aba3e25717850c26c9cd0d89d");
+
+ MessageDigest m = MessageDigest.getInstance("SHA-1");
+ m.update(TEST1.getBytes(StandardCharsets.UTF_8));
+ ObjectId m1 = ObjectId.fromRaw(m.digest());
+
+ SHA1 s = SHA1.newInstance();
+ s.update(TEST1.getBytes(StandardCharsets.UTF_8));
+ ObjectId s1 = ObjectId.fromRaw(s.digest());
+
+ s.reset();
+ s.update(TEST1.getBytes(StandardCharsets.UTF_8));
+ ObjectId s2 = s.toObjectId();
+
+ assertEquals(m1, s1);
+ assertEquals(exp, s1);
+ assertEquals(exp, s2);
+ }
+
+ @Test
+ public void test2() throws NoSuchAlgorithmException {
+ ObjectId exp = ObjectId
+ .fromString("84983e441c3bd26ebaae4aa1f95129e5e54670f1");
+
+ MessageDigest m = MessageDigest.getInstance("SHA-1");
+ m.update(TEST2.getBytes(StandardCharsets.UTF_8));
+ ObjectId m1 = ObjectId.fromRaw(m.digest());
+
+ SHA1 s = SHA1.newInstance();
+ s.update(TEST2.getBytes(StandardCharsets.UTF_8));
+ ObjectId s1 = ObjectId.fromRaw(s.digest());
+
+ s.reset();
+ s.update(TEST2.getBytes(StandardCharsets.UTF_8));
+ ObjectId s2 = s.toObjectId();
+
+ assertEquals(m1, s1);
+ assertEquals(exp, s1);
+ assertEquals(exp, s2);
+ }
+
+ @Test
+ public void shatteredCollision()
+ throws IOException, NoSuchAlgorithmException {
+ byte[] pdf1 = read("shattered-1.pdf", 422435);
+ byte[] pdf2 = read("shattered-2.pdf", 422435);
+ MessageDigest md;
+ SHA1 s;
+
+ // SHAttered attack generated these PDFs to have identical SHA-1.
+ ObjectId bad = ObjectId
+ .fromString("38762cf7f55934b34d179ae6a4c80cadccbb7f0a");
+ md = MessageDigest.getInstance("SHA-1");
+ md.update(pdf1);
+ assertEquals("shattered-1 collides", bad,
+ ObjectId.fromRaw(md.digest()));
+ s = SHA1.newInstance().setDetectCollision(false);
+ s.update(pdf1);
+ assertEquals("shattered-1 collides", bad, s.toObjectId());
+
+ md = MessageDigest.getInstance("SHA-1");
+ md.update(pdf2);
+ assertEquals("shattered-2 collides", bad,
+ ObjectId.fromRaw(md.digest()));
+ s = SHA1.newInstance().setDetectCollision(false);
+ s.update(pdf2);
+ assertEquals("shattered-2 collides", bad, s.toObjectId());
+
+ // SHA1 with detectCollision shouldn't be fooled.
+ s = SHA1.newInstance().setDetectCollision(true);
+ s.update(pdf1);
+ try {
+ s.digest();
+ fail("expected " + Sha1CollisionException.class.getSimpleName());
+ } catch (Sha1CollisionException e) {
+ assertEquals(e.getMessage(),
+ "SHA-1 collision detected on " + bad.name());
+ }
+
+ s = SHA1.newInstance().setDetectCollision(true);
+ s.update(pdf2);
+ try {
+ s.digest();
+ fail("expected " + Sha1CollisionException.class.getSimpleName());
+ } catch (Sha1CollisionException e) {
+ assertEquals(e.getMessage(),
+ "SHA-1 collision detected on " + bad.name());
+ }
+ }
+
+ @Test
+ public void shatteredStoredInGitBlob() throws IOException {
+ byte[] pdf1 = read("shattered-1.pdf", 422435);
+ byte[] pdf2 = read("shattered-2.pdf", 422435);
+
+ // Although the prior test detects the chance of a collision, adding
+ // the Git blob header permutes the data enough for this specific
+ // attack example to not be detected as a collision. (A different file
+ // pair that takes the Git header into account however, would.)
+ ObjectId id1 = blob(pdf1, SHA1.newInstance().setDetectCollision(true));
+ ObjectId id2 = blob(pdf2, SHA1.newInstance().setDetectCollision(true));
+
+ assertEquals(
+ ObjectId.fromString("ba9aaa145ccd24ef760cf31c74d8f7ca1a2e47b0"),
+ id1);
+ assertEquals(
+ ObjectId.fromString("b621eeccd5c7edac9b7dcba35a8d5afd075e24f2"),
+ id2);
+ }
+
+ @Test
+ public void detectsShatteredByDefault() throws IOException {
+ assumeTrue(System.getProperty("org.eclipse.jgit.util.sha1.detectCollision") == null);
+ assumeTrue(System.getProperty("org.eclipse.jgit.util.sha1.safeHash") == null);
+
+ byte[] pdf1 = read("shattered-1.pdf", 422435);
+ SHA1 s = SHA1.newInstance();
+ s.update(pdf1);
+ try {
+ s.digest();
+ fail("expected " + Sha1CollisionException.class.getSimpleName());
+ } catch (Sha1CollisionException e) {
+ assertTrue("shattered-1 detected", true);
+ }
+ }
+
+ private static ObjectId blob(byte[] pdf1, SHA1 s) {
+ s.update(Constants.encodedTypeString(Constants.OBJ_BLOB));
+ s.update((byte) ' ');
+ s.update(Constants.encodeASCII(pdf1.length));
+ s.update((byte) 0);
+ s.update(pdf1);
+ return s.toObjectId();
+ }
+
+ private byte[] read(String name, int sizeHint) throws IOException {
+ try (InputStream in = getClass().getResourceAsStream(name)) {
+ ByteBuffer buf = IO.readWholeStream(in, sizeHint);
+ byte[] r = new byte[buf.remaining()];
+ buf.get(r);
+ return r;
+ }
+ }
+}

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