Refactoring before supporting multiple NTP servers (08dac677) · Commits · e / os / android_frameworks_base

core/java/android/provider/Settings.java

+17 −1

Original line number	Diff line number	Diff line
		@@ -11998,7 +11998,23 @@ public final class Settings {
		public static final String NITZ_NETWORK_DISCONNECT_RETENTION =
		"nitz_network_disconnect_retention";

		/** Preferred NTP server. {@hide} */
		/**
		* The preferred NTP server. This setting overrides Android's static xml configuration when
		* present and valid.
		*
		* <p>The legacy form is the NTP server name as a string.
		* <p>Newer code should use the form: ntp://{server name}[:port] (the standard NTP port,
		* 123, is used if not specified).
		*
		* <p>For example, the following examples are valid:
		* <ul>
		* <li>time.android.com</li>
		* <li>ntp://time.android.com</li>
		* <li>ntp://time.android.com:123</li>
		* </ul>
		*
		* @hide
		*/
		@Readable
		public static final String NTP_SERVER = "ntp_server";
		/** Timeout in milliseconds to wait for NTP server. {@hide} */

core/java/android/util/NtpTrustedTime.java

+151 −77

Original line number	Diff line number	Diff line
		@@ -32,8 +32,11 @@ import android.provider.Settings;
		import android.text.TextUtils;

		import com.android.internal.annotations.GuardedBy;
		import com.android.internal.annotations.VisibleForTesting;

		import java.io.PrintWriter;
		import java.net.URI;
		import java.net.URISyntaxException;
		import java.time.Duration;
		import java.time.Instant;
		import java.util.Objects;
		@@ -49,6 +52,56 @@ import java.util.function.Supplier;
		*/
		public class NtpTrustedTime implements TrustedTime {

		private static final String URI_SCHEME_NTP = "ntp";

		/**
		* NTP server configuration.
		*
		* @hide
		*/
		public static final class NtpConfig {

		@NonNull private final URI mServerUri;
		@NonNull private final Duration mTimeout;

		/**
		* Creates an instance. If the arguments are invalid then an {@link
		* IllegalArgumentException} will be thrown. See {@link #parseNtpUriStrict(String)} and
		* {@link #parseNtpServerSetting(String)} to create valid URIs.
		*/
		public NtpConfig(@NonNull URI serverUri, @NonNull Duration timeout)
		throws IllegalArgumentException {
		try {
		mServerUri = validateNtpServerUri(Objects.requireNonNull(serverUri));
		} catch (URISyntaxException e) {
		throw new IllegalArgumentException("Bad URI", e);
		}

		if (timeout.isNegative() \|\| timeout.isZero()) {
		throw new IllegalArgumentException("timeout < 0");
		}
		mTimeout = timeout;
		}

		@NonNull
		public URI getServerUri() {
		return mServerUri;
		}

		@NonNull
		public Duration getTimeout() {
		return mTimeout;
		}

		@Override
		public String toString() {
		return "NtpConnectionInfo{"
		+ "mServerUri=" + mServerUri
		+ ", mTimeout=" + mTimeout
		+ '}';
		}
		}

		/**
		* The result of a successful NTP query.
		*
		@@ -139,15 +192,7 @@ public class NtpTrustedTime implements TrustedTime {

		/** An in-memory config override for use during tests. */
		@Nullable
		private String mHostnameForTests;

		/** An in-memory config override for use during tests. */
		@Nullable
		private Integer mPortForTests;

		/** An in-memory config override for use during tests. */
		@Nullable
		private Duration mTimeoutForTests;
		private NtpConfig mNtpConfigForTests;

		// Declared volatile and accessed outside of synchronized blocks to avoid blocking reads during
		// forceRefresh().
		@@ -170,19 +215,16 @@ public class NtpTrustedTime implements TrustedTime {
		* Overrides the NTP server config for tests. Passing {@code null} to a parameter clears the
		* test value, i.e. so the normal value will be used next time.
		*/
		public void setServerConfigForTests(
		@Nullable String hostname, @Nullable Integer port, @Nullable Duration timeout) {
		public void setServerConfigForTests(@NonNull NtpConfig ntpConfig) {
		synchronized (this) {
		mHostnameForTests = hostname;
		mPortForTests = port;
		mTimeoutForTests = timeout;
		mNtpConfigForTests = ntpConfig;
		}
		}

		@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
		public boolean forceRefresh() {
		synchronized (this) {
		NtpConnectionInfo connectionInfo = getNtpConnectionInfo();
		NtpConfig connectionInfo = getNtpConfig();
		if (connectionInfo == null) {
		// missing server config, so no NTP time available
		if (LOGD) Log.d(TAG, "forceRefresh: invalid server config");
		@@ -213,9 +255,11 @@ public class NtpTrustedTime implements TrustedTime {

		if (LOGD) Log.d(TAG, "forceRefresh() from cache miss");
		final SntpClient client = new SntpClient();
		final String serverName = connectionInfo.getServer();
		final int port = connectionInfo.getPort();
		final int timeoutMillis = connectionInfo.getTimeoutMillis();
		final URI ntpServerUri = connectionInfo.getServerUri();
		final String serverName = ntpServerUri.getHost();
		final int port = ntpServerUri.getPort() == -1
		? SntpClient.STANDARD_NTP_PORT : ntpServerUri.getPort();
		final int timeoutMillis = saturatedCast(connectionInfo.getTimeout().toMillis());
		if (client.requestTime(serverName, port, timeoutMillis, network)) {
		int ntpUncertaintyMillis = saturatedCast(client.getRoundTripTime() / 2);
		mTimeResult = new TimeResult(
		@@ -327,85 +371,115 @@ public class NtpTrustedTime implements TrustedTime {
		}
		}

		private static class NtpConnectionInfo {
		@GuardedBy("this")
		private NtpConfig getNtpConfig() {
		if (mNtpConfigForTests != null) {
		return mNtpConfigForTests;
		}

		final ContentResolver resolver = mContext.getContentResolver();
		final Resources res = mContext.getResources();

		@NonNull private final String mServer;
		private final int mPort;
		private final int mTimeoutMillis;
		// The Settings value has priority over static config. Check settings first.
		final String serverGlobalSetting =
		Settings.Global.getString(resolver, Settings.Global.NTP_SERVER);
		final URI settingsServerInfo = parseNtpServerSetting(serverGlobalSetting);

		NtpConnectionInfo(@NonNull String server, int port, int timeoutMillis) {
		mServer = Objects.requireNonNull(server);
		mPort = port;
		mTimeoutMillis = timeoutMillis;
		URI ntpServerUri;
		if (settingsServerInfo != null) {
		ntpServerUri = settingsServerInfo;
		} else {
		String configValue = res.getString(com.android.internal.R.string.config_ntpServer);
		try {
		ntpServerUri = parseNtpUriStrict(configValue);
		} catch (URISyntaxException e) {
		ntpServerUri = null;
		}

		@NonNull
		public String getServer() {
		return mServer;
		}

		@NonNull
		public int getPort() {
		return mPort;
		final int defaultTimeoutMillis =
		res.getInteger(com.android.internal.R.integer.config_ntpTimeout);
		final Duration timeout = Duration.ofMillis(Settings.Global.getInt(
		resolver, Settings.Global.NTP_TIMEOUT, defaultTimeoutMillis));
		return ntpServerUri == null ? null : new NtpConfig(ntpServerUri, timeout);
		}

		int getTimeoutMillis() {
		return mTimeoutMillis;
		/**
		* Parses and returns an NTP server config URI, or throws an exception if the URI doesn't
		* conform to expectations.
		*
		* <p>NTP server config URIs are in the form "ntp://{hostname}[:port]". This is not a registered
		* IANA URI scheme.
		*/
		public static URI parseNtpUriStrict(String ntpServerUriString) throws URISyntaxException {
		// java.net.URI is used in preference to android.net.Uri, since android.net.Uri is very
		// forgiving of obvious errors. URI catches issues sooner.
		URI unvalidatedUri = new URI(ntpServerUriString);
		return validateNtpServerUri(unvalidatedUri);
		}

		@Override
		public String toString() {
		return "NtpConnectionInfo{"
		+ "mServer='" + mServer + '\''
		+ ", mPort='" + mPort + '\''
		+ ", mTimeoutMillis=" + mTimeoutMillis
		+ '}';
		}
		/**
		* Parses a setting string and returns a URI that will be accepted by {@link NtpConfig}, or
		* {@code null} if the string does not produce a URI considered valid.
		*
		* <p>NTP server config URIs are in the form "ntp://{hostname}[:port]". This is not a registered
		* IANA URI scheme.
		*
		* <p>Unlike {@link #parseNtpUriStrict(String)} this method will not throw an exception. It
		* checks for a leading "ntp:" and will call through to {@link #parseNtpUriStrict(String)} to
		* attempt to parse it, returning {@code null} if it fails. To support legacy settings values,
		* it will also accept a string that only consists of a server name, which will be coerced into
		* a URI in the form "ntp://{server name}".
		*/
		@VisibleForTesting
		public static URI parseNtpServerSetting(String ntpServerSetting) {
		if (TextUtils.isEmpty(ntpServerSetting)) {
		return null;
		} else if (ntpServerSetting.startsWith(URI_SCHEME_NTP + ":")) {
		try {
		return parseNtpUriStrict(ntpServerSetting);
		} catch (URISyntaxException e) {
		Log.w(TAG, "Rejected NTP uri setting=" + ntpServerSetting, e);
		return null;
		}

		@GuardedBy("this")
		private NtpConnectionInfo getNtpConnectionInfo() {
		final ContentResolver resolver = mContext.getContentResolver();

		final Resources res = mContext.getResources();

		final String hostname;
		if (mHostnameForTests != null) {
		hostname = mHostnameForTests;
		} else {
		String serverGlobalSetting =
		Settings.Global.getString(resolver, Settings.Global.NTP_SERVER);
		if (serverGlobalSetting != null) {
		hostname = serverGlobalSetting;
		} else {
		hostname = res.getString(com.android.internal.R.string.config_ntpServer);
		// This is the legacy settings path. Assumes that the string is just a host name and
		// creates a URI in the form ntp://<host name>
		try {
		URI uri = new URI(URI_SCHEME_NTP, /host=/ntpServerSetting,
		/path=/null, /fragment=/null);
		// Paranoia: validate just in case the host name somehow results in a bad URI.
		return validateNtpServerUri(uri);
		} catch (URISyntaxException e) {
		Log.w(TAG, "Rejected NTP legacy setting=" + ntpServerSetting, e);
		return null;
		}
		}

		final Integer port;
		if (mPortForTests != null) {
		port = mPortForTests;
		} else {
		port = SntpClient.STANDARD_NTP_PORT;
		}

		final int timeoutMillis;
		if (mTimeoutForTests != null) {
		timeoutMillis = (int) mTimeoutForTests.toMillis();
		} else {
		int defaultTimeoutMillis =
		res.getInteger(com.android.internal.R.integer.config_ntpTimeout);
		timeoutMillis = Settings.Global.getInt(
		resolver, Settings.Global.NTP_TIMEOUT, defaultTimeoutMillis);
		/**
		* Checks that the supplied URI can be used to identify an NTP server.
		* This method currently ignores Uri components that are not used, only checking the parts that
		* must be present. Returns the supplied {@code uri} if validation is successful.
		*/
		private static URI validateNtpServerUri(URI uri) throws URISyntaxException {
		if (!uri.isAbsolute()) {
		throw new URISyntaxException(uri.toString(), "Relative URI not supported");
		}
		if (!URI_SCHEME_NTP.equals(uri.getScheme())) {
		throw new URISyntaxException(uri.toString(), "Unrecognized scheme");
		}
		String host = uri.getHost();
		if (TextUtils.isEmpty(host)) {
		throw new URISyntaxException(uri.toString(), "Missing host");
		}
		return TextUtils.isEmpty(hostname) ? null :
		new NtpConnectionInfo(hostname, port, timeoutMillis);
		return uri;
		}

		/** Prints debug information. */
		public void dump(PrintWriter pw) {
		synchronized (this) {
		pw.println("getNtpConnectionInfo()=" + getNtpConnectionInfo());
		pw.println("getNtpConfig()=" + getNtpConfig());
		pw.println("mTimeResult=" + mTimeResult);
		if (mTimeResult != null) {
		pw.println("mTimeResult.getAgeMillis()="

core/res/res/values/config.xml

+4 −2

Original line number	Diff line number	Diff line
		@@ -2308,8 +2308,10 @@
		it should be disabled in that locale's resources. -->
		<bool name="config_actionMenuItemAllCaps">true</bool>

		<!-- Remote server that can provide NTP responses. -->
		<string translatable="false" name="config_ntpServer">time.android.com</string>
		<!-- Remote server that can provide NTP responses.
		Values must be in the form: "ntp://<host>[:port]"
		This is not a registered IANA URI scheme. -->
		<string translatable="false" name="config_ntpServer">ntp://time.android.com</string>
		<!-- Normal polling frequency in milliseconds -->
		<integer name="config_ntpPollingInterval">64800000</integer>
		<!-- Try-again polling interval in milliseconds, in case the network request failed -->

core/tests/coretests/src/android/util/NtpTrustedTimeTest.java

0 → 100644

+141 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2022 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 android.util;

		import static org.junit.Assert.assertEquals;
		import static org.junit.Assert.assertNotNull;
		import static org.junit.Assert.assertNull;
		import static org.junit.Assert.assertThrows;

		import androidx.test.ext.junit.runners.AndroidJUnit4;
		import androidx.test.filters.SmallTest;

		import org.junit.Test;
		import org.junit.runner.RunWith;

		import java.net.URI;
		import java.net.URISyntaxException;
		import java.time.Duration;
		import java.util.Arrays;
		import java.util.List;
		import java.util.Map;

		@SmallTest
		@RunWith(AndroidJUnit4.class)
		public class NtpTrustedTimeTest {

		// Valid absolute URIs, but not ones that will be accepted as NTP server URIs.
		private static final List<String> BAD_ABSOLUTE_NTP_URIS = Arrays.asList(
		"ntp://:123/",
		"ntp://:123",
		"ntp://:/",
		"ntp://:",
		"ntp://foobar:abc/",
		"ntp://foobar:abc",
		"ntp://foobar:456:789/",
		"ntp://foobar:456:789",
		"ntp://foobar:456:abc/",
		"ntp://foobar:456:abc"
		);

		// Valid relative URIs, but not ones that will be accepted as NTP server URIs.
		private static final List<String> BAD_RELATIVE_NTP_URIS = Arrays.asList(
		"foobar",
		"/foobar",
		"foobar:456"
		);

		// Valid NTP server URIs: input value -> expected URI.toString() value.
		private static final Map<String, String> GOOD_NTP_URIS = Map.of(
		"ntp://foobar", "ntp://foobar",
		"ntp://foobar/", "ntp://foobar/",
		"ntp://foobar:456/", "ntp://foobar:456/",
		"ntp://foobar:456", "ntp://foobar:456"
		);

		private static final URI VALID_SERVER_URI = URI.create("ntp://foobar/");

		@Test
		public void testParseNtpServerSetting() {
		assertEquals(URI.create("ntp://foobar"), NtpTrustedTime.parseNtpServerSetting("foobar"));

		// Legacy settings values which could easily be confused with relative URIs. Parsing of this
		// legacy form doesn't have to be robust / treated as errors: Android has never supported
		// string like these, and so they won't work properly.
		assertNull(NtpTrustedTime.parseNtpServerSetting("foobar:123"));
		assertNull(NtpTrustedTime.parseNtpServerSetting("/foobar"));

		// NTP URI cases that must not be accepted.
		for (String badNtpUri : BAD_ABSOLUTE_NTP_URIS) {
		assertNull("Input: \"" + badNtpUri + "\"",
		NtpTrustedTime.parseNtpServerSetting(badNtpUri));
		}

		// Valid URIs
		for (Map.Entry<String, String> goodNtpUri : GOOD_NTP_URIS.entrySet()) {
		URI uri = NtpTrustedTime.parseNtpServerSetting(goodNtpUri.getKey());
		assertNotNull(goodNtpUri.getKey(), uri);
		assertEquals(goodNtpUri.getValue(), uri.toString());
		}
		}

		@Test
		public void testParseNtpUriStrict() throws Exception {
		// ntp: URI cases that must not be accepted.
		for (String badNtpUri : BAD_ABSOLUTE_NTP_URIS) {
		assertParseNtpUriStrictThrows(badNtpUri);
		}

		for (String badNtpUri : BAD_RELATIVE_NTP_URIS) {
		assertParseNtpUriStrictThrows(badNtpUri);
		}

		// Bad scheme.
		assertParseNtpUriStrictThrows("notntp://foobar:123");

		// Valid NTP URIs
		for (Map.Entry<String, String> goodNtpUri : GOOD_NTP_URIS.entrySet()) {
		URI uri = NtpTrustedTime.parseNtpUriStrict(goodNtpUri.getKey());
		assertNotNull(goodNtpUri.getKey(), uri);
		assertEquals(goodNtpUri.getValue(), uri.toString());
		}
		}

		private void assertParseNtpUriStrictThrows(String badNtpUri) throws Exception {
		assertThrows("Input: \"" + badNtpUri, URISyntaxException.class,
		() -> NtpTrustedTime.parseNtpUriStrict(badNtpUri));
		}

		@Test(expected = NullPointerException.class)
		public void testNtpConfig_nullConstructorServerInfo() {
		new NtpTrustedTime.NtpConfig(null, Duration.ofSeconds(5));
		}

		@Test(expected = NullPointerException.class)
		public void testNtpConfig_nullConstructorTimeout() {
		new NtpTrustedTime.NtpConfig(VALID_SERVER_URI, null);
		}

		@Test(expected = IllegalArgumentException.class)
		public void testNtpConfig_zeroTimeout() {
		new NtpTrustedTime.NtpConfig(VALID_SERVER_URI, Duration.ofMillis(0));
		}

		@Test(expected = IllegalArgumentException.class)
		public void testNtpConfig_negativeTimeout() {
		new NtpTrustedTime.NtpConfig(VALID_SERVER_URI, Duration.ofMillis(-1));
		}
		}

core/tests/coretests/src/android/util/OWNERS

0 → 100644

+2 −0

Original line number	Diff line number	Diff line
		per-file NtpTrustedTimeTest.java = file:/services/core/java/com/android/server/timezonedetector/OWNERS
		per-file TypedValueTest.kt = file:/core/java/android/content/res/OWNERS