WIP - DNS filtering. (5dfe6772) · Commits · e / os / orbotservice

build.gradle

+1 −0

Original line number	Diff line number	Diff line
		@@ -59,4 +59,5 @@ dependencies {
		// until a new full release is done
		implementation files('../libs/tor-android-binary-release.aar')

		implementation 'foundation.e:privacymodule.trackerfilter:2.0.0-dev'
		}

src/main/java/org/torproject/android/service/vpn/DNSResolver.java

+38 −4

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		package org.torproject.android.service.vpn;

		import android.content.Context;
		import android.util.Log;

		import org.pcap4j.packet.DnsPacket;
		import org.pcap4j.packet.IllegalRawDataException;
		import org.pcap4j.packet.namednumber.DnsRCode;

		import java.io.IOException;
		import java.net.DatagramPacket;
		import java.net.DatagramSocket;
		import java.net.InetAddress;

		import foundation.e.privacymodules.trackers.api.ShouldBlockDNSRequest;

		public class DNSResolver {

		private final int mPort;
		private InetAddress mLocalhost = null;
		private ShouldBlockDNSRequest hostnameFilter = null;

		public DNSResolver(int localPort) {
		public DNSResolver(Context context, int localPort) {
		hostnameFilter = ShouldBlockDNSRequest.Companion.getInstance(context);
		mPort = localPort;
		}

		public byte[] processDNS(byte[] payload) throws IOException {
		public DnsPacket processDNS(DnsPacket dnsRequest) throws IOException {
		DnsPacket dnsResponse = null;

		try {
		String host = dnsRequest.getHeader().getQuestions().get(0).getQName().getName();
		if (hostnameFilter.shouldBlock(host, ShouldBlockDNSRequest.DUMMY_APP_UID)) {
		dnsResponse = dnsRequest.getBuilder()
		.rCode(DnsRCode.NX_DOMAIN)
		.response(true).build();

		return dnsResponse;
		}
		} catch(Exception e) {
		Log.e("DNSResolver", "find host in question failed", e);
		}


		if (mLocalhost == null)
		mLocalhost = InetAddress.getLocalHost();

		byte[] payload = dnsRequest.getRawData();
		DatagramPacket packet = new DatagramPacket(
		payload, payload.length, mLocalhost, mPort
		);
		@@ -30,7 +57,14 @@ public class DNSResolver {
		packet = new DatagramPacket(buf, buf.length);
		datagramSocket.receive(packet);

		return packet.getData();
		byte[] dnsResp = packet.getData();
		if (dnsResp != null) {
		try {
		dnsResponse = DnsPacket.newPacket(dnsResp, 0, dnsResp.length);
		} catch (IllegalRawDataException e) {
		Log.e("DNSResolver", "Can't parse DNS response", e);
		}
		}
		return dnsResponse;
		}

		}

src/main/java/org/torproject/android/service/vpn/DNSResolverOLD.java

0 → 100644

+50 −0

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		package org.torproject.android.service.vpn;

		import android.util.Log;

		import org.pcap4j.packet.DnsPacket;
		import org.pcap4j.packet.IllegalRawDataException;

		import java.io.IOException;
		import java.net.DatagramPacket;
		import java.net.DatagramSocket;
		import java.net.InetAddress;

		public class DNSResolverOLD {

		private final int mPort;
		private InetAddress mLocalhost = null;

		public DNSResolverOLD(int localPort) {
		mPort = localPort;
		}

		public DnsPacket processDNS(DnsPacket dnsRequest) throws IOException {

		if (mLocalhost == null)
		mLocalhost = InetAddress.getLocalHost();

		byte[] payload = dnsRequest.getRawData();
		DatagramPacket packet = new DatagramPacket(
		payload, payload.length, mLocalhost, mPort
		);
		DatagramSocket datagramSocket = new DatagramSocket();
		datagramSocket.send(packet);

		// Await response from DNS server
		byte[] buf = new byte[1024];
		packet = new DatagramPacket(buf, buf.length);
		datagramSocket.receive(packet);

		byte[] dnsResp = packet.getData();
		DnsPacket dnsResponse = null;
		if (dnsResp != null) {
		try {
		dnsResponse = DnsPacket.newPacket(dnsResp, 0, dnsResp.length);
		} catch (IllegalRawDataException e) {
		Log.e("DNSResolver", "Can't parse DNS response", e);
		}
		}
		return dnsResponse;
		}
		}

src/main/java/org/torproject/android/service/vpn/OrbotVpnManager.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -276,7 +276,7 @@ public class OrbotVpnManager implements Handler.Callback, OrbotConstants {

		mInterface = builder.establish();

		mDnsResolver = new DNSResolver(mTorDns);
		mDnsResolver = new DNSResolver(mService.getApplicationContext(), mTorDns);

		final Handler handler = new Handler(Looper.getMainLooper());
		handler.postDelayed(() -> {

src/main/java/org/torproject/android/service/vpn/RequestPacketHandler.java

+3 −6

Original line number	Diff line number	Diff line
		@@ -29,14 +29,11 @@ public class RequestPacketHandler implements Runnable {
		public void run() {
		try {
		UdpPacket udpPacket = (UdpPacket) packet.getPayload();

		byte[] dnsResp = mDnsResolver.processDNS(udpPacket.getPayload().getRawData());

		if (dnsResp != null) {

		DnsPacket dnsRequest = (DnsPacket) udpPacket.getPayload();
		DnsPacket dnsResponse = DnsPacket.newPacket(dnsResp, 0, dnsResp.length);

		DnsPacket dnsResponse = mDnsResolver.processDNS(dnsRequest);

		if (dnsResponse != null) {
		DnsPacket.Builder dnsBuilder = new DnsPacket.Builder();
		dnsBuilder.questions(dnsRequest.getHeader().getQuestions());
		dnsBuilder.id(dnsRequest.getHeader().getId());