Merge "Change the logic of getting ntp server" (7024d920) · Commits · e / os / android_frameworks_base

core/java/android/net/SntpClient.java

+19 −9

Original line number	Diff line number	Diff line
		@@ -25,6 +25,7 @@ import com.android.internal.util.TrafficStatsConstants;
		import java.net.DatagramPacket;
		import java.net.DatagramSocket;
		import java.net.InetAddress;
		import java.net.UnknownHostException;
		import java.util.Arrays;

		/**
		@@ -86,21 +87,26 @@ public class SntpClient {
		* Sends an SNTP request to the given host and processes the response.
		*
		* @param host host name of the server.
		* @param timeout network timeout in milliseconds.
		* @param timeout network timeout in milliseconds. the timeout doesn't include the DNS lookup
		* time, and it applies to each individual query to the resolved addresses of
		* the NTP server.
		* @param network network over which to send the request.
		* @return true if the transaction was successful.
		*/
		public boolean requestTime(String host, int timeout, Network network) {
		final Network networkForResolv = network.getPrivateDnsBypassingCopy();
		InetAddress address = null;
		try {
		address = networkForResolv.getByName(host);
		} catch (Exception e) {
		final InetAddress[] addresses = networkForResolv.getAllByName(host);
		for (int i = 0; i < addresses.length; i++) {
		if (requestTime(addresses[i], NTP_PORT, timeout, networkForResolv)) return true;
		}
		} catch (UnknownHostException e) {
		Log.w(TAG, "Unknown host: " + host);
		EventLogTags.writeNtpFailure(host, e.toString());
		if (DBG) Log.d(TAG, "request time failed: " + e);
		return false;
		}
		return requestTime(address, NTP_PORT, timeout, networkForResolv);

		if (DBG) Log.d(TAG, "request time failed");
		return false;
		}

		public boolean requestTime(InetAddress address, int port, int timeout, Network network) {
		@@ -139,10 +145,11 @@ public class SntpClient {
		final long originateTime = readTimeStamp(buffer, ORIGINATE_TIME_OFFSET);
		final long receiveTime = readTimeStamp(buffer, RECEIVE_TIME_OFFSET);
		final long transmitTime = readTimeStamp(buffer, TRANSMIT_TIME_OFFSET);
		final long referenceTime = readTimeStamp(buffer, REFERENCE_TIME_OFFSET);

		/* Do validation according to RFC */
		// TODO: validate originateTime == requestTime.
		checkValidServerReply(leap, mode, stratum, transmitTime);
		checkValidServerReply(leap, mode, stratum, transmitTime, referenceTime);

		long roundTripTime = responseTicks - requestTicks - (transmitTime - receiveTime);
		// receiveTime = originateTime + transit + skew
		@@ -218,7 +225,7 @@ public class SntpClient {
		}

		private static void checkValidServerReply(
		byte leap, byte mode, int stratum, long transmitTime)
		byte leap, byte mode, int stratum, long transmitTime, long referenceTime)
		throws InvalidServerReplyException {
		if (leap == NTP_LEAP_NOSYNC) {
		throw new InvalidServerReplyException("unsynchronized server");
		@@ -232,6 +239,9 @@ public class SntpClient {
		if (transmitTime == 0) {
		throw new InvalidServerReplyException("zero transmitTime");
		}
		if (referenceTime == 0) {
		throw new InvalidServerReplyException("zero reference timestamp");
		}
		}

		/**