diff options
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.java | 254 |
1 files changed, 254 insertions, 0 deletions
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..abc2854faf --- /dev/null +++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/sha1/SHA1Test.java @@ -0,0 +1,254 @@ +/* + * Copyright (C) 2017, Google Inc. and others + * + * This program and the accompanying materials are made available under the + * terms of the Eclipse Distribution License v. 1.0 which is available at + * https://www.eclipse.org/org/documents/edl-v10.php. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +package org.eclipse.jgit.util.sha1; + +import static java.nio.charset.StandardCharsets.UTF_8; +import static org.junit.Assert.assertEquals; +import static org.junit.Assert.assertTrue; +import static org.junit.Assert.fail; +import static org.junit.Assume.assumeFalse; +import static org.junit.Assume.assumeTrue; + +import java.io.IOException; +import java.io.InputStream; +import java.nio.ByteBuffer; +import java.security.MessageDigest; +import java.security.NoSuchAlgorithmException; + +import org.eclipse.jgit.junit.MockSystemReader; +import org.eclipse.jgit.lib.Constants; +import org.eclipse.jgit.lib.ObjectId; +import org.eclipse.jgit.util.IO; +import org.eclipse.jgit.util.SystemReader; +import org.eclipse.jgit.util.sha1.SHA1.Sha1Implementation; +import org.junit.After; +import org.junit.Before; +import org.junit.experimental.theories.DataPoints; +import org.junit.experimental.theories.Theories; +import org.junit.experimental.theories.Theory; +import org.junit.runner.RunWith; + +@RunWith(Theories.class) +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; + + @DataPoints + public static Sha1Implementation[] getDataPoints() { + return new Sha1Implementation[] { Sha1Implementation.JAVA, + Sha1Implementation.JDKNATIVE }; + } + + private Sha1Implementation sha1Implementation; + + public SHA1Test(Sha1Implementation impl) { + this.sha1Implementation = impl; + } + + @Before + public void setUp() throws Exception { + MockSystemReader mockSystemReader = new MockSystemReader(); + SystemReader.setInstance(mockSystemReader); + System.setProperty("org.eclipse.jgit.util.sha1.implementation", + sha1Implementation.name()); + } + + @After + public void tearDown() { + SystemReader.setInstance(null); + } + + @Theory + 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); + } + + @Theory + public void test1() throws NoSuchAlgorithmException { + ObjectId exp = ObjectId + .fromString("a9993e364706816aba3e25717850c26c9cd0d89d"); + + MessageDigest m = MessageDigest.getInstance("SHA-1"); + m.update(TEST1.getBytes(UTF_8)); + ObjectId m1 = ObjectId.fromRaw(m.digest()); + + SHA1 s = SHA1.newInstance(); + s.update(TEST1.getBytes(UTF_8)); + ObjectId s1 = ObjectId.fromRaw(s.digest()); + + s.reset(); + s.update(TEST1.getBytes(UTF_8)); + ObjectId s2 = s.toObjectId(); + + assertEquals(m1, s1); + assertEquals(exp, s1); + assertEquals(exp, s2); + } + + @Theory + public void test2() throws NoSuchAlgorithmException { + ObjectId exp = ObjectId + .fromString("84983e441c3bd26ebaae4aa1f95129e5e54670f1"); + + MessageDigest m = MessageDigest.getInstance("SHA-1"); + m.update(TEST2.getBytes(UTF_8)); + ObjectId m1 = ObjectId.fromRaw(m.digest()); + + SHA1 s = SHA1.newInstance(); + s.update(TEST2.getBytes(UTF_8)); + ObjectId s1 = ObjectId.fromRaw(s.digest()); + + s.reset(); + s.update(TEST2.getBytes(UTF_8)); + ObjectId s2 = s.toObjectId(); + + assertEquals(m1, s1); + assertEquals(exp, s1); + assertEquals(exp, s2); + } + + @Theory + public void shatteredCollision() + throws IOException, NoSuchAlgorithmException { + assumeFalse( + System.getProperty("org.eclipse.jgit.util.sha1.implementation") + .equalsIgnoreCase("jdkNative")); + + 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()); + } + } + + @Theory + public void shatteredStoredInGitBlob() throws IOException { + assumeFalse( + System.getProperty("org.eclipse.jgit.util.sha1.implementation") + .equalsIgnoreCase("jdkNative")); + + 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); + } + + @Theory + public void detectsShatteredByDefault() throws IOException { + assumeFalse( + System.getProperty("org.eclipse.jgit.util.sha1.implementation") + .equalsIgnoreCase("jdkNative")); + + 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; + } + } +} |