Move DnsPacket to libs net (f08f9d4b) · Commits · e / os / android_frameworks_base

core/java/android/net/DnsPacket.java

deleted100644 → 0

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		/*
		* Copyright (C) 2019 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.net;

		import android.annotation.NonNull;
		import android.annotation.Nullable;
		import android.text.TextUtils;

		import com.android.internal.util.BitUtils;

		import java.nio.BufferUnderflowException;
		import java.nio.ByteBuffer;
		import java.text.DecimalFormat;
		import java.text.FieldPosition;
		import java.util.ArrayList;
		import java.util.List;

		/**
		* Defines basic data for DNS protocol based on RFC 1035.
		* Subclasses create the specific format used in DNS packet.
		*
		* @hide
		*/
		public abstract class DnsPacket {
		public class DnsHeader {
		private static final String TAG = "DnsHeader";
		public final int id;
		public final int flags;
		public final int rcode;
		private final int[] mRecordCount;

		/**
		* Create a new DnsHeader 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 header.
		* 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;
		mRecordCount = new int[NUM_SECTIONS];
		for (int i = 0; i < NUM_SECTIONS; ++i) {
		mRecordCount[i] = BitUtils.uint16(buf.getShort());
		}
		}

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

		/**
		* Superclass 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;
		private static final int NAME_NORMAL = 0;
		private static final int NAME_COMPRESSION = 0xC0;
		private final DecimalFormat byteFormat = new DecimalFormat();
		private final FieldPosition pos = new FieldPosition(0);

		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[] mRdata;

		/**
		* Create a new DnsRecord from a positioned ByteBuffer.
		*
		* 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.
		*
		* @param ByteBuffer input of record, must be in network byte order
		* (which is the default).
		*/
		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: " + dName.length());
		}
		nsType = BitUtils.uint16(buf.getShort());
		nsClass = BitUtils.uint16(buf.getShort());

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

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

		/**
		* Convert label from {@code byte[]} to {@code String}
		*
		* 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();
		for (int i = 0; i < label.length; ++i) {
		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);
		}
		}
		return sb.toString();
		}

		private String parseName(@NonNull ByteBuffer buf, int depth) throws
		BufferUnderflowException, ParseException {
		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) {
		return "";
		} else if (mask != NAME_NORMAL && mask != NAME_COMPRESSION) {
		throw new ParseException("Parse name fail, bad label type");
		} else if (mask == NAME_COMPRESSION) {
		// Name compression based on RFC 1035 - 4.1.4 Message compression
		final int offset = ((len & ~NAME_COMPRESSION) << 8) + BitUtils.uint8(buf.get());
		final int oldPos = buf.position();
		if (offset >= oldPos - 2) {
		throw new ParseException("Parse compression name fail, invalid compression");
		}
		buf.position(offset);
		final String pointed = parseName(buf, depth + 1);
		buf.position(oldPos);
		return pointed;
		} else {
		final byte[] label = new byte[len];
		buf.get(label);
		final String head = labelToString(label);
		if (head.length() > MAXLABELSIZE) {
		throw new ParseException("Parse name fail, invalid label length");
		}
		final String tail = parseName(buf, depth + 1);
		return TextUtils.isEmpty(tail) ? head : head + "." + tail;
		}
		}
		}

		public static final int QDSECTION = 0;
		public static final int ANSECTION = 1;
		public static final int NSSECTION = 2;
		public static final int ARSECTION = 3;
		private static final int NUM_SECTIONS = ARSECTION + 1;

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

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

		protected DnsPacket(@NonNull byte[] data) throws ParseException {
		if (null == data) throw new ParseException("Parse header failed, null input data");
		final ByteBuffer buffer;
		try {
		buffer = ByteBuffer.wrap(data);
		mHeader = new DnsHeader(buffer);
		} catch (BufferUnderflowException e) {
		throw new ParseException("Parse Header fail, bad input data", e);
		}

		mRecords = new ArrayList[NUM_SECTIONS];

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

core/java/android/net/DnsResolver.java

+12 −3

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		@@ -38,6 +38,8 @@ import android.os.MessageQueue;
		import android.system.ErrnoException;
		import android.util.Log;

		import com.android.net.module.util.DnsPacket;

		import java.io.FileDescriptor;
		import java.lang.annotation.Retention;
		import java.lang.annotation.RetentionPolicy;
		@@ -97,7 +99,7 @@ public final class DnsResolver {
		@interface DnsError {}
		/**
		* Indicates that there was an error parsing the response the query.
		* The cause of this error is available via getCause() and is a ParseException.
		* The cause of this error is available via getCause() and is a {@link ParseException}.
		*/
		public static final int ERROR_PARSE = 0;
		/**
		@@ -290,8 +292,15 @@ public final class DnsResolver {
		}
		try {
		mAllAnswers.addAll(new DnsAddressAnswer(answer).getAddresses());
		} catch (ParseException e) {
		mDnsException = new DnsException(ERROR_PARSE, e);
		} catch (DnsPacket.ParseException e) {
		// Convert the com.android.net.module.util.DnsPacket.ParseException to an
		// android.net.ParseException. This is the type that was used in Q and is implied
		// by the public documentation of ERROR_PARSE.
		//
		// DnsPacket cannot throw android.net.ParseException directly because it's @hide.
		ParseException pe = new ParseException(e.reason, e.getCause());
		pe.setStackTrace(e.getStackTrace());
		mDnsException = new DnsException(ERROR_PARSE, pe);
		}
		maybeReportAnswer();
		}

packages/Tethering/jarjar-rules.txt

+3 −0

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		@@ -15,3 +15,6 @@ rule com.android.internal.util.TrafficStatsConstants* com.android.networkstack.t
		rule android.net.LocalLog* com.android.networkstack.tethering.LocalLog@1

		rule android.net.shared.Inet4AddressUtils* com.android.networkstack.tethering.shared.Inet4AddressUtils@1

		# Classes from net-utils-framework-common
		rule com.android.net.module.util.** com.android.networkstack.tethering.util.@1
		No newline at end of file

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

deleted100644 → 0

+0 −159

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		/*
		* Copyright (C) 2019 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.net;

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

		import androidx.test.filters.SmallTest;
		import androidx.test.runner.AndroidJUnit4;

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

		import java.util.Arrays;
		import java.util.List;

		@RunWith(AndroidJUnit4.class)
		@SmallTest
		public class DnsPacketTest {
		private void assertHeaderParses(DnsPacket.DnsHeader header, int id, int flag,
		int qCount, int aCount, int nsCount, int arCount) {
		assertEquals(header.id, id);
		assertEquals(header.flags, flag);
		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 assertRecordParses(DnsPacket.DnsRecord record, String dname,
		int dtype, int dclass, int ttl, byte[] 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 {
		TestDnsPacket(byte[] data) throws ParseException {
		super(data);
		}

		public DnsHeader getHeader() {
		return mHeader;
		}
		public List<DnsRecord> getRecordList(int secType) {
		return mRecords[secType];
		}
		}

		@Test
		public void testNullDisallowed() {
		try {
		new TestDnsPacket(null);
		fail("Exception not thrown for null byte array");
		} catch (ParseException e) {
		}
		}

		@Test
		public void testV4Answer() throws Exception {
		final byte[] v4blob = new byte[] {
		/* Header */
		0x55, 0x66, /* Transaction ID */
		(byte) 0x81, (byte) 0x80, /* Flags */
		0x00, 0x01, /* Questions */
		0x00, 0x01, /* Answer RRs */
		0x00, 0x00, /* Authority RRs */
		0x00, 0x00, /* Additional RRs */
		/* Queries */
		0x03, 0x77, 0x77, 0x77, 0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6c, 0x65,
		0x03, 0x63, 0x6f, 0x6d, 0x00, /* Name */
		0x00, 0x01, /* Type */
		0x00, 0x01, /* Class */
		/* Answers */
		(byte) 0xc0, 0x0c, /* Name */
		0x00, 0x01, /* Type */
		0x00, 0x01, /* Class */
		0x00, 0x00, 0x01, 0x2b, /* TTL */
		0x00, 0x04, /* Data length */
		(byte) 0xac, (byte) 0xd9, (byte) 0xa1, (byte) 0x84 /* Address */
		};
		TestDnsPacket packet = new TestDnsPacket(v4blob);

		// Header part
		assertHeaderParses(packet.getHeader(), 0x5566, 0x8180, 1, 1, 0, 0);

		// 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.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 });
		}

		@Test
		public void testV6Answer() throws Exception {
		final byte[] v6blob = new byte[] {
		/* Header */
		0x77, 0x22, /* Transaction ID */
		(byte) 0x81, (byte) 0x80, /* Flags */
		0x00, 0x01, /* Questions */
		0x00, 0x01, /* Answer RRs */
		0x00, 0x00, /* Authority RRs */
		0x00, 0x00, /* Additional RRs */
		/* Queries */
		0x03, 0x77, 0x77, 0x77, 0x06, 0x67, 0x6F, 0x6F, 0x67, 0x6c, 0x65,
		0x03, 0x63, 0x6f, 0x6d, 0x00, /* Name */
		0x00, 0x1c, /* Type */
		0x00, 0x01, /* Class */
		/* Answers */
		(byte) 0xc0, 0x0c, /* Name */
		0x00, 0x1c, /* Type */
		0x00, 0x01, /* Class */
		0x00, 0x00, 0x00, 0x37, /* TTL */
		0x00, 0x10, /* Data length */
		0x24, 0x04, 0x68, 0x00, 0x40, 0x05, 0x08, 0x0d,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0x04 /* Address */
		};
		TestDnsPacket packet = new TestDnsPacket(v6blob);

		// Header part
		assertHeaderParses(packet.getHeader(), 0x7722, 0x8180, 1, 1, 0, 0);

		// 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.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 });
		}
		}