Merge "Use sha256 of a string as seed in RapporEncoder.insecureEncoder" into pi-dev (651ac4d1) · Commits · e / os / android_frameworks_base

core/java/android/privacy/internal/rappor/RapporEncoder.java

+16 −1

Original line number	Original line	Diff line number	Diff line
	@@ -20,6 +20,10 @@ import android.privacy.DifferentialPrivacyEncoder;

	import com.google.android.rappor.Encoder;		import com.google.android.rappor.Encoder;

			import java.nio.ByteBuffer;
			import java.nio.charset.StandardCharsets;
			import java.security.MessageDigest;
			import java.security.NoSuchAlgorithmException;
	import java.security.SecureRandom;		import java.security.SecureRandom;
	import java.util.Random;		import java.util.Random;

	@@ -66,7 +70,7 @@ public class RapporEncoder implements DifferentialPrivacyEncoder {
	random = sSecureRandom;		random = sSecureRandom;
	} else {		} else {
	// To have deterministic result by hard coding encoder id as seed.		// To have deterministic result by hard coding encoder id as seed.
	random = new Random((long) config.mEncoderId.hashCode());		random = new Random(getInsecureSeed(config.mEncoderId));
	userSecret = INSECURE_SECRET;		userSecret = INSECURE_SECRET;
	}		}
	mEncoder = new Encoder(random, null, null,		mEncoder = new Encoder(random, null, null,
	@@ -75,6 +79,17 @@ public class RapporEncoder implements DifferentialPrivacyEncoder {
	config.mNumCohorts, config.mNumBloomHashes);		config.mNumCohorts, config.mNumBloomHashes);
	}		}

			private long getInsecureSeed(String input) {
			try {
			MessageDigest digest = MessageDigest.getInstance("SHA-256");
			byte[] bytes = digest.digest(input.getBytes(StandardCharsets.UTF_8));
			return ByteBuffer.wrap(bytes).getLong();
			} catch (NoSuchAlgorithmException e) {
			// Should not happen
			throw new AssertionError("Unable generate insecure seed");
			}
			}

	/**		/**
	* Create {@link RapporEncoder} with {@link RapporConfig} and user secret provided.		* Create {@link RapporEncoder} with {@link RapporConfig} and user secret provided.
	*		*

core/tests/privacytests/Android.mk

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -8,7 +8,7 @@ LOCAL_MODULE_TAGS := tests
	LOCAL_SRC_FILES := \		LOCAL_SRC_FILES := \
	$(call all-java-files-under, src)		$(call all-java-files-under, src)

	LOCAL_STATIC_JAVA_LIBRARIES := junit rappor-tests android-support-test		LOCAL_STATIC_JAVA_LIBRARIES := junit rappor-tests android-support-test truth-prebuilt

	LOCAL_JAVA_LIBRARIES := android.test.runner		LOCAL_JAVA_LIBRARIES := android.test.runner
	LOCAL_PACKAGE_NAME := FrameworksPrivacyLibraryTests		LOCAL_PACKAGE_NAME := FrameworksPrivacyLibraryTests

core/tests/privacytests/src/android/privacy/LongitudinalReportingEncoderTest.java

+37 −11

Original line number	Original line	Diff line number	Diff line
	@@ -16,6 +16,7 @@

	package android.privacy;		package android.privacy;

			import static com.google.common.truth.Truth.assertThat;
	import static org.junit.Assert.assertEquals;		import static org.junit.Assert.assertEquals;
	import static org.junit.Assert.assertFalse;		import static org.junit.Assert.assertFalse;
	import static org.junit.Assert.assertTrue;		import static org.junit.Assert.assertTrue;
	@@ -72,27 +73,27 @@ public class LongitudinalReportingEncoderTest {
	final LongitudinalReportingEncoder encoder =		final LongitudinalReportingEncoder encoder =
	LongitudinalReportingEncoder.createInsecureEncoderForTest(		LongitudinalReportingEncoder.createInsecureEncoderForTest(
	config);		config);
	assertEquals(0, encoder.encodeBoolean(true)[0]);
	assertEquals(0, encoder.encodeBoolean(true)[0]);
	assertEquals(1, encoder.encodeBoolean(true)[0]);		assertEquals(1, encoder.encodeBoolean(true)[0]);
	assertEquals(0, encoder.encodeBoolean(true)[0]);
	assertEquals(1, encoder.encodeBoolean(true)[0]);		assertEquals(1, encoder.encodeBoolean(true)[0]);
	assertEquals(1, encoder.encodeBoolean(true)[0]);		assertEquals(1, encoder.encodeBoolean(true)[0]);
			assertEquals(0, encoder.encodeBoolean(true)[0]);
	assertEquals(1, encoder.encodeBoolean(true)[0]);		assertEquals(1, encoder.encodeBoolean(true)[0]);
	assertEquals(1, encoder.encodeBoolean(true)[0]);		assertEquals(1, encoder.encodeBoolean(true)[0]);
	assertEquals(1, encoder.encodeBoolean(true)[0]);		assertEquals(1, encoder.encodeBoolean(true)[0]);
	assertEquals(1, encoder.encodeBoolean(true)[0]);		assertEquals(1, encoder.encodeBoolean(true)[0]);
			assertEquals(0, encoder.encodeBoolean(true)[0]);
			assertEquals(0, encoder.encodeBoolean(true)[0]);

	assertEquals(0, encoder.encodeBoolean(false)[0]);		assertEquals(0, encoder.encodeBoolean(false)[0]);
	assertEquals(1, encoder.encodeBoolean(false)[0]);		assertEquals(1, encoder.encodeBoolean(false)[0]);
	assertEquals(1, encoder.encodeBoolean(false)[0]);		assertEquals(1, encoder.encodeBoolean(false)[0]);
	assertEquals(1, encoder.encodeBoolean(false)[0]);
	assertEquals(0, encoder.encodeBoolean(false)[0]);		assertEquals(0, encoder.encodeBoolean(false)[0]);
	assertEquals(0, encoder.encodeBoolean(false)[0]);		assertEquals(0, encoder.encodeBoolean(false)[0]);
	assertEquals(1, encoder.encodeBoolean(false)[0]);
	assertEquals(0, encoder.encodeBoolean(false)[0]);		assertEquals(0, encoder.encodeBoolean(false)[0]);
	assertEquals(1, encoder.encodeBoolean(false)[0]);		assertEquals(0, encoder.encodeBoolean(false)[0]);
	assertEquals(1, encoder.encodeBoolean(false)[0]);		assertEquals(0, encoder.encodeBoolean(false)[0]);
			assertEquals(0, encoder.encodeBoolean(false)[0]);
			assertEquals(0, encoder.encodeBoolean(false)[0]);

	// Test if IRR returns original result when f = 0		// Test if IRR returns original result when f = 0
	final LongitudinalReportingConfig config2 = new LongitudinalReportingConfig(		final LongitudinalReportingConfig config2 = new LongitudinalReportingConfig(
	@@ -127,6 +128,31 @@ public class LongitudinalReportingEncoderTest {
	}		}
	}		}

			@Test
			public void testLongitudinalReportingInsecureEncoder_setSeedCorrectly() throws Exception {
			final int n = 10000;
			final double f = 0.35;
			final double expectedTrueSum = n * f;
			final double valueRange = 5 * Math.sqrt(n * f * (1 - f));
			int trueSum = 0;
			for (int i = 0; i < n; i++) {
			final LongitudinalReportingConfig config = new LongitudinalReportingConfig(
			"encoder" + i, // encoderId
			f, // probabilityF
			0, // probabilityP
			1); // probabilityQ
			final LongitudinalReportingEncoder encoder
			= LongitudinalReportingEncoder.createInsecureEncoderForTest(config);
			boolean encodedFalse = encoder.encodeBoolean(false)[0] > 0;
			if (encodedFalse) {
			trueSum += 1;
			}
			}
			// Total number of true(s) should be around the mean (10000 * 0.35)
			assertThat((double) trueSum).isLessThan(expectedTrueSum + valueRange);
			assertThat((double) trueSum).isAtLeast(expectedTrueSum - valueRange);
			}

	@Test		@Test
	public void testLongitudinalReportingEncoder_basicPRRTest() throws Exception {		public void testLongitudinalReportingEncoder_basicPRRTest() throws Exception {
	// Should always return original value when p = 0		// Should always return original value when p = 0
	@@ -290,8 +316,8 @@ public class LongitudinalReportingEncoderTest {
	}		}
	}		}
	// Total number of true(s) should be around the mean (1000 * 0.8)		// Total number of true(s) should be around the mean (1000 * 0.8)
	assertTrue(trueSum1 < expectedTrueSum1 + valueRange1);		assertThat((double) trueSum1).isLessThan(expectedTrueSum1 + valueRange1);
	assertTrue(trueSum1 > expectedTrueSum1 - valueRange1);		assertThat((double) trueSum1).isAtLeast(expectedTrueSum1 - valueRange1);

	// Confirm if PRR randomizer is working correctly		// Confirm if PRR randomizer is working correctly
	final int n2 = 1000;		final int n2 = 1000;
	@@ -314,8 +340,8 @@ public class LongitudinalReportingEncoderTest {
	}		}
	}		}
	// Total number of true(s) should be around the mean (1000 * 0.2)		// Total number of true(s) should be around the mean (1000 * 0.2)
	assertTrue(trueSum2 < expectedTrueSum2 + valueRange2);		assertThat((double) trueSum2).isLessThan(expectedTrueSum2 + valueRange2);
	assertTrue(trueSum2 > expectedTrueSum2 - valueRange2);		assertThat((double) trueSum2).isAtLeast(expectedTrueSum2 - valueRange2);
	}		}

	@Test		@Test

core/tests/privacytests/src/android/privacy/RapporEncoderTest.java

+9 −8

Original line number	Original line	Diff line number	Diff line
	@@ -79,11 +79,11 @@ public class RapporEncoderTest {
	public void testRapporEncoder_IRRWithPRR() throws Exception {		public void testRapporEncoder_IRRWithPRR() throws Exception {
	int numBits = 8;		int numBits = 8;
	final long inputValue = 254L;		final long inputValue = 254L;
	final long prrValue = 250L;		final long expectedPrrValue = 126L;
	final long prrAndIrrValue = 244L;		final long expectedPrrAndIrrValue = 79L;

	final RapporConfig config1 = new RapporConfig(		final RapporConfig config1 = new RapporConfig(
	"Foo", // encoderId		"Foo2", // encoderId
	numBits, // numBits,		numBits, // numBits,
	0.25, // probabilityF		0.25, // probabilityF
	0, // probabilityP		0, // probabilityP
	@@ -93,12 +93,12 @@ public class RapporEncoderTest {
	// Use insecure encoder here as we want to get the exact output.		// Use insecure encoder here as we want to get the exact output.
	final RapporEncoder encoder1 = RapporEncoder.createInsecureEncoderForTest(config1);		final RapporEncoder encoder1 = RapporEncoder.createInsecureEncoderForTest(config1);
	// Verify that PRR is working as expected.		// Verify that PRR is working as expected.
	assertEquals(prrValue, toLong(encoder1.encodeBits(toBytes(inputValue))));		assertEquals(expectedPrrValue, toLong(encoder1.encodeBits(toBytes(inputValue))));
	assertTrue(encoder1.isInsecureEncoderForTest());		assertTrue(encoder1.isInsecureEncoderForTest());

	// Verify that IRR is working as expected.		// Verify that IRR is working as expected.
	final RapporConfig config2 = new RapporConfig(		final RapporConfig config2 = new RapporConfig(
	"Foo", // encoderId		"Foo2", // encoderId
	numBits, // numBits,		numBits, // numBits,
	0, // probabilityF		0, // probabilityF
	0.3, // probabilityP		0.3, // probabilityP
	@@ -107,11 +107,12 @@ public class RapporEncoderTest {
	2); // numBloomHashes		2); // numBloomHashes
	// Use insecure encoder here as we want to get the exact output.		// Use insecure encoder here as we want to get the exact output.
	final RapporEncoder encoder2 = RapporEncoder.createInsecureEncoderForTest(config2);		final RapporEncoder encoder2 = RapporEncoder.createInsecureEncoderForTest(config2);
	assertEquals(prrAndIrrValue, toLong(encoder2.encodeBits(toBytes(prrValue))));		assertEquals(expectedPrrAndIrrValue,
			toLong(encoder2.encodeBits(toBytes(expectedPrrValue))));

	// Test that end-to-end is the result of PRR + IRR.		// Test that end-to-end is the result of PRR + IRR.
	final RapporConfig config3 = new RapporConfig(		final RapporConfig config3 = new RapporConfig(
	"Foo", // encoderId		"Foo2", // encoderId
	numBits, // numBits,		numBits, // numBits,
	0.25, // probabilityF		0.25, // probabilityF
	0.3, // probabilityP		0.3, // probabilityP
	@@ -120,7 +121,7 @@ public class RapporEncoderTest {
	2); // numBloomHashes		2); // numBloomHashes
	final RapporEncoder encoder3 = RapporEncoder.createInsecureEncoderForTest(config3);		final RapporEncoder encoder3 = RapporEncoder.createInsecureEncoderForTest(config3);
	// Verify that PRR is working as expected.		// Verify that PRR is working as expected.
	assertEquals(prrAndIrrValue, toLong(encoder3.encodeBits(toBytes(inputValue))));		assertEquals(expectedPrrAndIrrValue, toLong(encoder3.encodeBits(toBytes(inputValue))));
	}		}

	@Test		@Test

services/tests/servicestests/src/com/android/server/net/watchlist/PrivacyUtilsTests.java

+3 −3

Original line number	Original line	Diff line number	Diff line
	@@ -75,11 +75,11 @@ public class PrivacyUtilsTests {
	Map<String, Boolean> result = PrivacyUtils.createDpEncodedReportMap(false, null,		Map<String, Boolean> result = PrivacyUtils.createDpEncodedReportMap(false, null,
	TEST_DIGEST_LIST, TEST_AGGREGATED_RESULT1);		TEST_DIGEST_LIST, TEST_AGGREGATED_RESULT1);
	assertEquals(6, result.size());		assertEquals(6, result.size());
	assertTrue(result.get("C86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB48"));		assertFalse(result.get("C86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB48"));
	assertTrue(result.get("C86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB49"));		assertTrue(result.get("C86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB49"));
	assertTrue(result.get("C86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB47"));		assertTrue(result.get("C86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB47"));
	assertFalse(result.get("E86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB45"));		assertTrue(result.get("E86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB45"));
	assertTrue(result.get("C86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB44"));		assertFalse(result.get("C86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB44"));
	assertTrue(result.get("B86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB43"));		assertTrue(result.get("B86F9D37425340B635F43D6BC2506630761ADA71F5E6BBDBCA4651C479F9FB43"));
	}		}