Merge "[BluetoothMetrics] Create new bloom filter for medical device identification" into main (114f3b44) · Commits · e / os / android_packages_modules_Bluetooth

android/app/src/com/android/bluetooth/btservice/MedicalDeviceBloomfilterGenerator.java

0 → 100644

+76 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2023 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.bluetooth.btservice;

		import java.io.File;
		import java.io.FileOutputStream;
		import java.io.IOException;

		/** Class to generate a medical device bloomfilter */
		public class MedicalDeviceBloomfilterGenerator {

		public static final String BLOOM_FILTER_DEFAULT =
		"01070000003C01002106584044800850055"
		+ "002308488410020D9A00001138410510000"
		+ "000042004200000000000C2000000040064"
		+ "0120080020110412A500090520210040C40"
		+ "4002601040005004400148414006198A041"
		+ "00890000600400000800210041810600800"
		+ "0142208000721A030000028102448201110"
		+ "0002007120020101448C211490A2B000084"
		+ "C010004004C00C080808200026210608110"
		+ "200011200000015000000212C4400040802"
		+ "00111114840000001002080040186000404"
		+ "81C064400052381109017039900000200C9"
		+ "C0002E6480000101C40000601064001A018"
		+ "40440280A810001000040455A0404617034"
		+ "50000140040D020020C6204100804041600"
		+ "80840002000800804280028000440000122"
		+ "00808409905022000590000110448080400"
		+ "561004210020430092602000040C0090C00"
		+ "C18480020000519C1482100111011120390"
		+ "02C0000228208104800C050440000004040"
		+ "00871400882400140080000005308124900"
		+ "104000040002410508CA349000200000202"
		+ "90200920181890100800110220A20874820"
		+ "0428080054A0005101C0820060090080040"
		+ "6820C480F40081014010201800000018101"
		+ "208914100321008006520002030010800C4"
		+ "1022C000048206002010041220000008021"
		+ "002080314040000100030002008";

		/** Provide byte[] version of a given string */
		public static byte[] hexStringToByteArray(String s) {
		int len = s.length();
		byte[] data = new byte[len / 2];
		for (int i = 0; i < len; i += 2) {
		data[i / 2] =
		(byte)
		((Character.digit(s.charAt(i), 16) << 4)
		+ Character.digit(s.charAt(i + 1), 16));
		}
		return data;
		}

		/** Generate bloom filter file given filePath */
		public static void generateDefaultBloomfilter(String filePath) throws IOException {
		File outputFile = new File(filePath);
		outputFile.createNewFile(); // if file already exists will do nothing
		FileOutputStream fos = new FileOutputStream(filePath);
		fos.write(hexStringToByteArray(BLOOM_FILTER_DEFAULT));
		fos.close();
		}
		}

android/app/src/com/android/bluetooth/btservice/MetricsLogger.java

+99 −12

Original line number	Diff line number	Diff line
		@@ -96,7 +96,10 @@ public class MetricsLogger {
		private static final String TAG = "BluetoothMetricsLogger";
		private static final String BLOOMFILTER_PATH = "/data/misc/bluetooth";
		private static final String BLOOMFILTER_FILE = "/devices_for_metrics_v3";
		private static final String MEDICAL_DEVICE_BLOOMFILTER_FILE = "/medical_devices_for_metrics_v1";
		public static final String BLOOMFILTER_FULL_PATH = BLOOMFILTER_PATH + BLOOMFILTER_FILE;
		public static final String MEDICAL_DEVICE_BLOOMFILTER_FULL_PATH =
		BLOOMFILTER_PATH + MEDICAL_DEVICE_BLOOMFILTER_FILE;

		// 6 hours timeout for counter metrics
		private static final long BLUETOOTH_COUNTER_METRICS_ACTION_DURATION_MILLIS = 6L * 3600L * 1000L;
		@@ -114,6 +117,10 @@ public class MetricsLogger {
		private BloomFilter<byte[]> mBloomFilter = null;
		protected boolean mBloomFilterInitialized = false;

		private BloomFilter<byte[]> mMedicalDeviceBloomFilter = null;

		protected boolean mMedicalDeviceBloomFilterInitialized = false;

		private AlarmManager.OnAlarmListener mOnAlarmListener =
		new AlarmManager.OnAlarmListener() {
		@Override
		@@ -185,10 +192,48 @@ public class MetricsLogger {
		return true;
		}

		/** Initialize medical device bloom filter */
		public boolean initMedicalDeviceBloomFilter(String path) {
		try {
		File medicalDeviceFile = new File(path);
		if (!medicalDeviceFile.exists()) {
		Log.w(TAG, "MetricsLogger is creating a new medical device Bloomfilter file");
		MedicalDeviceBloomfilterGenerator.generateDefaultBloomfilter(path);
		}

		FileInputStream inputStream = new FileInputStream(new File(path));
		mMedicalDeviceBloomFilter =
		BloomFilter.readFrom(inputStream, Funnels.byteArrayFunnel());
		mMedicalDeviceBloomFilterInitialized = true;
		} catch (IOException e1) {
		Log.w(TAG, "MetricsLogger can't read the medical device BloomFilter file.");
		byte[] bloomfilterData =
		MedicalDeviceBloomfilterGenerator.hexStringToByteArray(
		MedicalDeviceBloomfilterGenerator.BLOOM_FILTER_DEFAULT);
		try {
		mMedicalDeviceBloomFilter =
		BloomFilter.readFrom(
		new ByteArrayInputStream(bloomfilterData),
		Funnels.byteArrayFunnel());
		mMedicalDeviceBloomFilterInitialized = true;
		Log.i(TAG, "The medical device bloomfilter is used");
		return true;
		} catch (IOException e2) {
		Log.w(TAG, "The medical device bloomfilter can't be used.");
		}
		return false;
		}
		return true;
		}

		protected void setBloomfilter(BloomFilter bloomfilter) {
		mBloomFilter = bloomfilter;
		}

		protected void setMedicalDeviceBloomfilter(BloomFilter bloomfilter) {
		mMedicalDeviceBloomFilter = bloomfilter;
		}

		void init(AdapterService adapterService, RemoteDevices remoteDevices) {
		if (mInitialized) {
		return;
		@@ -203,6 +248,12 @@ public class MetricsLogger {
		// We still want to use this class even if the bloomfilter isn't initialized
		// so still return true here.
		}
		if (!initMedicalDeviceBloomFilter(MEDICAL_DEVICE_BLOOMFILTER_FULL_PATH)) {
		Log.w(TAG, "MetricsLogger can't initialize the medical device bloomfilter");
		// The class is for multiple metrics tasks.
		// We still want to use this class even if the bloomfilter isn't initialized
		// so still return true here.
		}
		IntentFilter filter = new IntentFilter();
		filter.setPriority(IntentFilter.SYSTEM_HIGH_PRIORITY);
		filter.addAction(BluetoothA2dp.ACTION_CONNECTION_STATE_CHANGED);
		@@ -289,7 +340,8 @@ public class MetricsLogger {
		BluetoothDevice device = connIntent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
		int state = connIntent.getIntExtra(BluetoothProfile.EXTRA_STATE, -1);
		int metricId = mAdapterService.getMetricId(device);
		byte[] remoteDeviceInfoBytes = getRemoteDeviceInfoProto(device);
		boolean includeMedicalDevices = false;
		byte[] remoteDeviceInfoBytes = getRemoteDeviceInfoProto(device, includeMedicalDevices);
		if (state == BluetoothProfile.STATE_CONNECTING) {
		String deviceName = mRemoteDevices.getName(device);
		BluetoothStatsLog.write(
		@@ -417,6 +469,7 @@ public class MetricsLogger {
		mAdapterService = null;
		mInitialized = false;
		mBloomFilterInitialized = false;
		mMedicalDeviceBloomFilterInitialized = false;
		}

		protected void cancelPendingDrain() {
		@@ -446,15 +499,31 @@ public class MetricsLogger {

		/**
		* Retrieves a byte array containing serialized remote device information for the specified
		* BluetoothDevice. This data can be used for remote device identification and logging.
		* BluetoothDevice. This data can be used for remote device identification and logging. Does not
		* include medical remote devices.
		*
		* @param device The BluetoothDevice for which to retrieve device information.
		* @return A byte array containing the serialized remote device information.
		*/
		public byte[] getRemoteDeviceInfoProto(BluetoothDevice device) {
		if (!mInitialized) {
		return null;
		return mInitialized ? buildRemoteDeviceInfoProto(device, false) : null;
		}

		/**
		* Retrieves a byte array containing serialized remote device information for the specified
		* BluetoothDevice. This data can be used for remote device identification and logging.
		*
		* @param device The BluetoothDevice for which to retrieve device information.
		* @param includeMedicalDevices Should be true only if logging as de-identified metric,
		* otherwise false.
		* @return A byte array containing the serialized remote device information.
		*/
		public byte[] getRemoteDeviceInfoProto(BluetoothDevice device, boolean includeMedicalDevices) {
		return mInitialized ? buildRemoteDeviceInfoProto(device, includeMedicalDevices) : null;
		}

		private byte[] buildRemoteDeviceInfoProto(
		BluetoothDevice device, boolean includeMedicalDevices) {
		ProtoOutputStream proto = new ProtoOutputStream();

		// write Allowlisted Device Name Hash
		@@ -463,7 +532,8 @@ public class MetricsLogger {
		ProtoOutputStream.FIELD_TYPE_STRING,
		ProtoOutputStream.FIELD_COUNT_SINGLE,
		BluetoothRemoteDeviceInformation.ALLOWLISTED_DEVICE_NAME_HASH_FIELD_NUMBER,
		getAllowlistedDeviceNameHash(mAdapterService.getRemoteName(device)));
		getAllowlistedDeviceNameHash(
		mAdapterService.getRemoteName(device), includeMedicalDevices));

		// write COD
		writeFieldIfNotNull(
		@@ -567,7 +637,7 @@ public class MetricsLogger {
		}
		}

		private String getMatchedString(List<String> wordBreakdownList) {
		private String getMatchedString(List<String> wordBreakdownList, boolean includeMedicalDevices) {
		if (!mBloomFilterInitialized \|\| wordBreakdownList.isEmpty()) {
		return "";
		}
		@@ -579,6 +649,21 @@ public class MetricsLogger {
		matchedString = word;
		}
		}

		return (matchedString.equals("") && includeMedicalDevices)
		? getMatchedStringForMedicalDevice(wordBreakdownList)
		: matchedString;
		}

		private String getMatchedStringForMedicalDevice(List<String> wordBreakdownList) {
		String matchedString = "";
		for (String word : wordBreakdownList) {
		byte[] sha256 = getSha256(word);
		if (mMedicalDeviceBloomFilter.mightContain(sha256)
		&& word.length() > matchedString.length()) {
		matchedString = word;
		}
		}
		return matchedString;
		}

		@@ -664,16 +749,18 @@ public class MetricsLogger {
		advDurationMs);
		}

		protected String getAllowlistedDeviceNameHash(String deviceName) {
		protected String getAllowlistedDeviceNameHash(
		String deviceName, boolean includeMedicalDevices) {
		List<String> wordBreakdownList = getWordBreakdownList(deviceName);
		String matchedString = getMatchedString(wordBreakdownList);
		String matchedString = getMatchedString(wordBreakdownList, includeMedicalDevices);
		return getSha256String(matchedString);
		}

		protected String logAllowlistedDeviceNameHash(
		int metricId, String deviceName, boolean logRestrictedNames) {
		List<String> wordBreakdownList = getWordBreakdownList(deviceName);
		String matchedString = getMatchedString(wordBreakdownList);
		boolean includeMedicalDevices = false;
		String matchedString = getMatchedString(wordBreakdownList, includeMedicalDevices);
		if (logRestrictedNames) {
		// Log the restricted bluetooth device name
		if (SdkLevel.isAtLeastU()) {
		@@ -705,7 +792,7 @@ public class MetricsLogger {
		state,
		uid,
		mAdapterService.getMetricId(device),
		getRemoteDeviceInfoProto(device));
		getRemoteDeviceInfoProto(device, false));
		}

		protected static String getSha256String(String name) {
		@@ -836,6 +923,6 @@ public class MetricsLogger {
		latencyPaSyncMs,
		latencyBisSyncMs,
		syncStatus,
		getRemoteDeviceInfoProto(device));
		getRemoteDeviceInfoProto(device, false));
		}
		}

android/app/tests/unit/src/com/android/bluetooth/btservice/MetricsLoggerTest.java

+22 −0

Original line number	Diff line number	Diff line
		@@ -269,6 +269,28 @@ public class MetricsLoggerTest {
		}
		}

		@Test
		public void testGetAllowlistedDeviceNameHashForMedicalDevice() {
		String deviceName = "Sam's rphonak hearing aid";
		String expectMedicalDeviceSha256 = MetricsLogger.getSha256String("rphonakhearingaid");

		String actualMedicalDeviceSha256 =
		mTestableMetricsLogger.getAllowlistedDeviceNameHash(deviceName, true);

		Assert.assertEquals(expectMedicalDeviceSha256, actualMedicalDeviceSha256);
		}

		@Test
		public void testGetAllowlistedDeviceNameHashForMedicalDeviceIdentifiedLogging() {
		String deviceName = "Sam's rphonak hearing aid";
		String expectMedicalDeviceSha256 = "";

		String actualMedicalDeviceSha256 =
		mTestableMetricsLogger.getAllowlistedDeviceNameHash(deviceName, false);

		Assert.assertEquals(expectMedicalDeviceSha256, actualMedicalDeviceSha256);
		}

		@Test
		public void uploadEmptyDeviceName() {
		initTestingBloomfilter();