Merge "Minor changes to the async DNS query JAVA API" (c8dfb728) · Commits · e / os / android_frameworks_base

core/java/android/net/DnsPacket.java

+43 −34

Original line number	Diff line number	Diff line
		@@ -28,7 +28,6 @@ import java.text.DecimalFormat;
		import java.text.FieldPosition;
		import java.util.ArrayList;
		import java.util.List;
		import java.util.StringJoiner;

		/**
		* Defines basic data for DNS protocol based on RFC 1035.
		@@ -42,7 +41,7 @@ public abstract class DnsPacket {
		public final int id;
		public final int flags;
		public final int rcode;
		private final int[] mSectionCount;
		private final int[] mRecordCount;

		/**
		* Create a new DnsHeader from a positioned ByteBuffer.
		@@ -52,27 +51,32 @@ public abstract class DnsPacket {
		* When this constructor returns, the reading position of the ByteBuffer has been
		* advanced to the end of the DNS header record.
		* This is meant to chain with other methods reading a DNS response in sequence.
		*
		*/
		DnsHeader(@NonNull ByteBuffer buf) throws BufferUnderflowException {
		id = BitUtils.uint16(buf.getShort());
		flags = BitUtils.uint16(buf.getShort());
		rcode = flags & 0xF;
		mSectionCount = new int[NUM_SECTIONS];
		mRecordCount = new int[NUM_SECTIONS];
		for (int i = 0; i < NUM_SECTIONS; ++i) {
		mSectionCount[i] = BitUtils.uint16(buf.getShort());
		mRecordCount[i] = BitUtils.uint16(buf.getShort());
		}
		}

		/**
		* Get section count by section type.
		* Get record count by type.
		*/
		public int getSectionCount(int sectionType) {
		return mSectionCount[sectionType];
		public int getRecordCount(int type) {
		return mRecordCount[type];
		}
		}

		public class DnsSection {
		/**
		* It's used both for DNS questions and DNS resource records.
		*
		* DNS questions (No TTL/RDATA)
		* DNS resource records (With TTL/RDATA)
		*/
		public class DnsRecord {
		private static final int MAXNAMESIZE = 255;
		private static final int MAXLABELSIZE = 63;
		private static final int MAXLABELCOUNT = 128;
		@@ -81,57 +85,57 @@ public abstract class DnsPacket {
		private final DecimalFormat byteFormat = new DecimalFormat();
		private final FieldPosition pos = new FieldPosition(0);

		private static final String TAG = "DnsSection";
		private static final String TAG = "DnsRecord";

		public final String dName;
		public final int nsType;
		public final int nsClass;
		public final long ttl;
		private final byte[] mRR;
		private final byte[] mRdata;

		/**
		* Create a new DnsSection from a positioned ByteBuffer.
		* Create a new DnsRecord from a positioned ByteBuffer.
		*
		* The ByteBuffer must be in network byte order (which is the default).
		* Reads the passed ByteBuffer from its current position and decodes a DNS section.
		* @param ByteBuffer input of record, must be in network byte order
		* (which is the default).
		* Reads the passed ByteBuffer from its current position and decodes a DNS record.
		* When this constructor returns, the reading position of the ByteBuffer has been
		* advanced to the end of the DNS header record.
		* This is meant to chain with other methods reading a DNS response in sequence.
		*
		*/
		DnsSection(int sectionType, @NonNull ByteBuffer buf)
		DnsRecord(int recordType, @NonNull ByteBuffer buf)
		throws BufferUnderflowException, ParseException {
		dName = parseName(buf, 0 /* Parse depth */);
		if (dName.length() > MAXNAMESIZE) {
		throw new ParseException("Parse name fail, name size is too long");
		throw new ParseException(
		"Parse name fail, name size is too long: " + dName.length());
		}
		nsType = BitUtils.uint16(buf.getShort());
		nsClass = BitUtils.uint16(buf.getShort());

		if (sectionType != QDSECTION) {
		if (recordType != QDSECTION) {
		ttl = BitUtils.uint32(buf.getInt());
		final int length = BitUtils.uint16(buf.getShort());
		mRR = new byte[length];
		buf.get(mRR);
		mRdata = new byte[length];
		buf.get(mRdata);
		} else {
		ttl = 0;
		mRR = null;
		mRdata = null;
		}
		}

		/**
		* Get a copy of rr.
		* Get a copy of rdata.
		*/
		@Nullable public byte[] getRR() {
		return (mRR == null) ? null : mRR.clone();
		@Nullable
		public byte[] getRR() {
		return (mRdata == null) ? null : mRdata.clone();
		}

		/**
		* Convert label from {@code byte[]} to {@code String}
		*
		* It follows the same converting rule as native layer.
		* (See ns_name.c in libc)
		*
		* Follows the same conversion rules of the native code (ns_name.c in libc)
		*/
		private String labelToString(@NonNull byte[] label) {
		final StringBuffer sb = new StringBuffer();
		@@ -139,13 +143,16 @@ public abstract class DnsPacket {
		int b = BitUtils.uint8(label[i]);
		// Control characters and non-ASCII characters.
		if (b <= 0x20 \|\| b >= 0x7f) {
		// Append the byte as an escaped decimal number, e.g., "\19" for 0x13.
		sb.append('\\');
		byteFormat.format(b, sb, pos);
		} else if (b == '"' \|\| b == '.' \|\| b == ';' \|\| b == '\\'
		\|\| b == '(' \|\| b == ')' \|\| b == '@' \|\| b == '$') {
		// Append the byte as an escaped character, e.g., "\:" for 0x3a.
		sb.append('\\');
		sb.append((char) b);
		} else {
		// Append the byte as a character, e.g., "a" for 0x61.
		sb.append((char) b);
		}
		}
		@@ -154,7 +161,9 @@ public abstract class DnsPacket {

		private String parseName(@NonNull ByteBuffer buf, int depth) throws
		BufferUnderflowException, ParseException {
		if (depth > MAXLABELCOUNT) throw new ParseException("Parse name fails, too many labels");
		if (depth > MAXLABELCOUNT) {
		throw new ParseException("Failed to parse name, too many labels");
		}
		final int len = BitUtils.uint8(buf.get());
		final int mask = len & NAME_COMPRESSION;
		if (0 == len) {
		@@ -194,7 +203,7 @@ public abstract class DnsPacket {
		private static final String TAG = DnsPacket.class.getSimpleName();

		protected final DnsHeader mHeader;
		protected final List<DnsSection>[] mSections;
		protected final List<DnsRecord>[] mRecords;

		public static class ParseException extends Exception {
		public ParseException(String msg) {
		@@ -216,18 +225,18 @@ public abstract class DnsPacket {
		throw new ParseException("Parse Header fail, bad input data", e);
		}

		mSections = new ArrayList[NUM_SECTIONS];
		mRecords = new ArrayList[NUM_SECTIONS];

		for (int i = 0; i < NUM_SECTIONS; ++i) {
		final int count = mHeader.getSectionCount(i);
		final int count = mHeader.getRecordCount(i);
		if (count > 0) {
		mSections[i] = new ArrayList(count);
		mRecords[i] = new ArrayList(count);
		}
		for (int j = 0; j < count; ++j) {
		try {
		mSections[i].add(new DnsSection(i, buffer));
		mRecords[i].add(new DnsRecord(i, buffer));
		} catch (BufferUnderflowException e) {
		throw new ParseException("Parse section fail", e);
		throw new ParseException("Parse record fail", e);
		}
		}
		}

core/java/android/net/DnsResolver.java

+8 −5

Original line number	Diff line number	Diff line
		@@ -43,6 +43,9 @@ import java.util.function.Consumer;
		/**
		* Dns resolver class for asynchronous dns querying
		*
		* Note that if a client sends a query with more than 1 record in the question section but
		* the remote dns server does not support this, it may not respond at all, leading to a timeout.
		*
		*/
		public final class DnsResolver {
		private static final String TAG = "DnsResolver";
		@@ -226,19 +229,19 @@ public final class DnsResolver {
		if (mHeader.rcode != 0) {
		throw new ParseException("Response error, rcode:" + mHeader.rcode);
		}
		if (mHeader.getSectionCount(ANSECTION) == 0) {
		if (mHeader.getRecordCount(ANSECTION) == 0) {
		throw new ParseException("No available answer");
		}
		if (mHeader.getSectionCount(QDSECTION) == 0) {
		if (mHeader.getRecordCount(QDSECTION) == 0) {
		throw new ParseException("No question found");
		}
		// Assume only one question per answer packet. (RFC1035)
		mQueryType = mSections[QDSECTION].get(0).nsType;
		// Expect only one question in question section.
		mQueryType = mRecords[QDSECTION].get(0).nsType;
		}

		public @NonNull List<InetAddress> getAddresses() {
		final List<InetAddress> results = new ArrayList<InetAddress>();
		for (final DnsSection ansSec : mSections[ANSECTION]) {
		for (final DnsRecord ansSec : mRecords[ANSECTION]) {
		// Only support A and AAAA, also ignore answers if query type != answer type.
		int nsType = ansSec.nsType;
		if (nsType != mQueryType \|\| (nsType != TYPE_A && nsType != TYPE_AAAA)) {

tests/net/java/android/net/DnsPacketTest.java

+30 −30

Original line number	Diff line number	Diff line
		@@ -36,19 +36,19 @@ public class DnsPacketTest {
		int qCount, int aCount, int nsCount, int arCount) {
		assertEquals(header.id, id);
		assertEquals(header.flags, flag);
		assertEquals(header.getSectionCount(DnsPacket.QDSECTION), qCount);
		assertEquals(header.getSectionCount(DnsPacket.ANSECTION), aCount);
		assertEquals(header.getSectionCount(DnsPacket.NSSECTION), nsCount);
		assertEquals(header.getSectionCount(DnsPacket.ARSECTION), arCount);
		assertEquals(header.getRecordCount(DnsPacket.QDSECTION), qCount);
		assertEquals(header.getRecordCount(DnsPacket.ANSECTION), aCount);
		assertEquals(header.getRecordCount(DnsPacket.NSSECTION), nsCount);
		assertEquals(header.getRecordCount(DnsPacket.ARSECTION), arCount);
		}

		private void assertSectionParses(DnsPacket.DnsSection section, String dname,
		private void assertRecordParses(DnsPacket.DnsRecord record, String dname,
		int dtype, int dclass, int ttl, byte[] rr) {
		assertEquals(section.dName, dname);
		assertEquals(section.nsType, dtype);
		assertEquals(section.nsClass, dclass);
		assertEquals(section.ttl, ttl);
		assertTrue(Arrays.equals(section.getRR(), rr));
		assertEquals(record.dName, dname);
		assertEquals(record.nsType, dtype);
		assertEquals(record.nsClass, dclass);
		assertEquals(record.ttl, ttl);
		assertTrue(Arrays.equals(record.getRR(), rr));
		}

		class TestDnsPacket extends DnsPacket {
		@@ -59,8 +59,8 @@ public class DnsPacketTest {
		public DnsHeader getHeader() {
		return mHeader;
		}
		public List<DnsSection> getSectionList(int secType) {
		return mSections[secType];
		public List<DnsRecord> getRecordList(int secType) {
		return mRecords[secType];
		}
		}

		@@ -101,16 +101,16 @@ public class DnsPacketTest {
		// Header part
		assertHeaderParses(packet.getHeader(), 0x5566, 0x8180, 1, 1, 0, 0);

		// Section part
		List<DnsPacket.DnsSection> qdSectionList =
		packet.getSectionList(DnsPacket.QDSECTION);
		assertEquals(qdSectionList.size(), 1);
		assertSectionParses(qdSectionList.get(0), "www.google.com", 1, 1, 0, null);
		// Record part
		List<DnsPacket.DnsRecord> qdRecordList =
		packet.getRecordList(DnsPacket.QDSECTION);
		assertEquals(qdRecordList.size(), 1);
		assertRecordParses(qdRecordList.get(0), "www.google.com", 1, 1, 0, null);

		List<DnsPacket.DnsSection> anSectionList =
		packet.getSectionList(DnsPacket.ANSECTION);
		assertEquals(anSectionList.size(), 1);
		assertSectionParses(anSectionList.get(0), "www.google.com", 1, 1, 0x12b,
		List<DnsPacket.DnsRecord> anRecordList =
		packet.getRecordList(DnsPacket.ANSECTION);
		assertEquals(anRecordList.size(), 1);
		assertRecordParses(anRecordList.get(0), "www.google.com", 1, 1, 0x12b,
		new byte[]{ (byte) 0xac, (byte) 0xd9, (byte) 0xa1, (byte) 0x84 });
		}

		@@ -143,16 +143,16 @@ public class DnsPacketTest {
		// Header part
		assertHeaderParses(packet.getHeader(), 0x7722, 0x8180, 1, 1, 0, 0);

		// Section part
		List<DnsPacket.DnsSection> qdSectionList =
		packet.getSectionList(DnsPacket.QDSECTION);
		assertEquals(qdSectionList.size(), 1);
		assertSectionParses(qdSectionList.get(0), "www.google.com", 28, 1, 0, null);
		// Record part
		List<DnsPacket.DnsRecord> qdRecordList =
		packet.getRecordList(DnsPacket.QDSECTION);
		assertEquals(qdRecordList.size(), 1);
		assertRecordParses(qdRecordList.get(0), "www.google.com", 28, 1, 0, null);

		List<DnsPacket.DnsSection> anSectionList =
		packet.getSectionList(DnsPacket.ANSECTION);
		assertEquals(anSectionList.size(), 1);
		assertSectionParses(anSectionList.get(0), "www.google.com", 28, 1, 0x37,
		List<DnsPacket.DnsRecord> anRecordList =
		packet.getRecordList(DnsPacket.ANSECTION);
		assertEquals(anRecordList.size(), 1);
		assertRecordParses(anRecordList.get(0), "www.google.com", 28, 1, 0x37,
		new byte[]{ 0x24, 0x04, 0x68, 0x00, 0x40, 0x05, 0x08, 0x0d,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0x04 });
		}