Support serializing a StructNdOptPref64 to a ByteBuffer. am: 568b689f6d am:... (1574a825) · Commits · e / os / android_packages_modules_NetworkStack

common/netlinkclient/src/android/net/netlink/StructNdOptPref64.java

+34 −2

Original line number	Diff line number	Diff line
		@@ -44,6 +44,7 @@ import java.nio.ByteBuffer;
		public class StructNdOptPref64 extends NdOption {
		public static final int STRUCT_SIZE = 16;
		public static final int TYPE = 38;
		public static final byte LENGTH = 2;

		private static final String TAG = StructNdOptPref64.class.getSimpleName();

		@@ -55,7 +56,7 @@ public class StructNdOptPref64 extends NdOption {
		/** The NAT64 prefix. */
		public final IpPrefix prefix;

		int plcToPrefixLength(int plc) {
		static int plcToPrefixLength(int plc) {
		switch (plc) {
		case 0: return 96;
		case 1: return 64;
		@@ -68,10 +69,30 @@ public class StructNdOptPref64 extends NdOption {
		}
		}

		static int prefixLengthToPlc(int prefixLength) {
		switch (prefixLength) {
		case 96: return 0;
		case 64: return 1;
		case 56: return 2;
		case 48: return 3;
		case 40: return 4;
		case 32: return 5;
		default:
		throw new IllegalArgumentException("Invalid prefix length " + prefixLength);
		}
		}

		/**
		* Returns the 2-byte "scaled lifetime and prefix length code" field: 13-bit lifetime, 3-bit PLC
		*/
		static short getScaledLifetimePlc(int lifetime, int prefixLengthCode) {
		return (short) ((lifetime & 0xfff8) \| (prefixLengthCode & 0x7));
		}

		public StructNdOptPref64(@NonNull ByteBuffer buf) {
		super(buf.get(), Byte.toUnsignedInt(buf.get()));
		if (type != TYPE) throw new IllegalArgumentException("Invalid type " + type);
		if (length != 2) throw new IllegalArgumentException("Invalid length " + length);
		if (length != LENGTH) throw new IllegalArgumentException("Invalid length " + length);

		int scaledLifetimePlc = Short.toUnsignedInt(buf.getShort());
		lifetime = scaledLifetimePlc & 0xfff8;
		@@ -108,6 +129,17 @@ public class StructNdOptPref64 extends NdOption {
		}
		}

		/** Outputs the wire format of the option to a new big-endian ByteBuffer. */
		public ByteBuffer toByteBuffer() {
		ByteBuffer buf = ByteBuffer.allocate(STRUCT_SIZE);
		buf.put(type);
		buf.put((byte) length);
		buf.putShort(getScaledLifetimePlc(lifetime, prefixLengthToPlc(prefix.getPrefixLength())));
		buf.put(prefix.getRawAddress(), 0, 12);
		buf.flip();
		return buf;
		}

		@Override
		@NonNull
		public String toString() {

tests/unit/src/android/net/netlink/StructNdOptPref64Test.java

+30 −7

Original line number	Diff line number	Diff line
		@@ -16,8 +16,13 @@

		package android.net.netlink;

		import static android.net.netlink.StructNdOptPref64.getScaledLifetimePlc;
		import static android.net.netlink.StructNdOptPref64.plcToPrefixLength;
		import static android.net.netlink.StructNdOptPref64.prefixLengthToPlc;

		import static org.junit.Assert.assertEquals;
		import static org.junit.Assert.assertNull;
		import static org.junit.Assert.fail;

		import android.net.IpPrefix;

		@@ -57,11 +62,9 @@ public class StructNdOptPref64Test {
		assertEquals(prefix, opt.prefix);
		}

		/**
		* Returns the 2-byte "scaled lifetime and prefix length code" field: 13-bit lifetime, 3-bit PLC
		*/
		private short getPref64ScaledLifetimePlc(int lifetime, int prefixLengthCode) {
		return (short) ((lifetime & 0xfff8) \| (prefixLengthCode & 0x7));
		private void assertToByteBufferMatches(StructNdOptPref64 opt, String expected) {
		String actual = HexEncoding.encodeToString(opt.toByteBuffer().array(), false /upperCase/);
		assertEquals(expected, actual);
		}

		private ByteBuffer makeNdOptPref64(int lifetime, byte[] prefix, int prefixLengthCode) {
		@@ -69,8 +72,8 @@ public class StructNdOptPref64Test {

		ByteBuffer buf = ByteBuffer.allocate(16)
		.put((byte) StructNdOptPref64.TYPE)
		.put((byte) 2) // len=2 (16 bytes)
		.putShort(getPref64ScaledLifetimePlc(lifetime, prefixLengthCode))
		.put((byte) StructNdOptPref64.LENGTH)
		.putShort(getScaledLifetimePlc(lifetime, prefixLengthCode))
		.put(prefix, 0, 12);

		buf.flip();
		@@ -85,6 +88,7 @@ public class StructNdOptPref64Test {
		byte[] rawBytes = HexEncoding.decode(hexBytes);
		StructNdOptPref64 opt = StructNdOptPref64.parse(ByteBuffer.wrap(rawBytes));
		assertPref64OptMatches(136, prefix("2001:db8:3:4:5:6::", 96), opt);
		assertToByteBufferMatches(opt, hexBytes);

		hexBytes = "2602" // type=38, len=2 (16 bytes)
		+ "2752" // lifetime=10064, PLC=2 (/56)
		@@ -92,6 +96,7 @@ public class StructNdOptPref64Test {
		rawBytes = HexEncoding.decode(hexBytes);
		opt = StructNdOptPref64.parse(ByteBuffer.wrap(rawBytes));
		assertPref64OptMatches(10064, prefix("64:ff9b::", 56), opt);
		assertToByteBufferMatches(opt, hexBytes);
		}

		@Test
		@@ -152,4 +157,22 @@ public class StructNdOptPref64Test {
		assertPref64OptMatches(600, prefix(PREFIX1, 40), opt);
		assertEquals("NdOptPref64(64:ff9b::/40, 600)", opt.toString());
		}

		private void assertInvalidPlc(int plc) {
		try {
		plcToPrefixLength(plc);
		fail("Invalid plc " + plc + " should have thrown exception");
		} catch (IllegalArgumentException expected) { }
		}

		@Test
		public void testPrefixLengthPlc() {
		for (int i = 0; i < 6; i++) {
		assertEquals(i, prefixLengthToPlc(plcToPrefixLength(i)));
		}
		assertInvalidPlc(-1);
		assertInvalidPlc(6);
		assertInvalidPlc(7);
		assertEquals(0, prefixLengthToPlc(96));
		}
		}