Merge "Detect upstream hotspot device type by checking the vendor specific IE." into rvc-dev

4 files changed, 204 insertions, 14 deletions

diff --git a/src/android/net/ip/IpClient.java b/src/android/net/ip/IpClient.java
index bfeac8b..ebb31c6 100644
--- a/src/android/net/ip/IpClient.java
+++ b/src/android/net/ip/IpClient.java
@@ -20,6 +20,7 @@ import static android.net.RouteInfo.RTN_UNICAST;
 import static android.net.shared.IpConfigurationParcelableUtil.toStableParcelable;
 import static android.provider.DeviceConfig.NAMESPACE_CONNECTIVITY;
 
+import static com.android.server.util.NetworkStackConstants.VENDOR_SPECIFIC_IE_ID;
 import static com.android.server.util.PermissionUtil.enforceNetworkStackCallingPermission;
 
 import android.content.Context;
@@ -40,10 +41,13 @@ import android.net.Uri;
 import android.net.apf.ApfCapabilities;
 import android.net.apf.ApfFilter;
 import android.net.dhcp.DhcpClient;
+import android.net.dhcp.DhcpPacket;
 import android.net.metrics.IpConnectivityLog;
 import android.net.metrics.IpManagerEvent;
 import android.net.shared.InitialConfiguration;
 import android.net.shared.ProvisioningConfiguration;
+import android.net.shared.ProvisioningConfiguration.ScanResultInfo;
+import android.net.shared.ProvisioningConfiguration.ScanResultInfo.InformationElement;
 import android.net.util.InterfaceParams;
 import android.net.util.NetworkStackUtils;
 import android.net.util.SharedLog;
@@ -64,6 +68,7 @@ import android.util.SparseArray;
 import androidx.annotation.NonNull;
 
 import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.HexDump;
 import com.android.internal.util.IState;
 import com.android.internal.util.IndentingPrintWriter;
 import com.android.internal.util.MessageUtils;
@@ -80,6 +85,10 @@ import com.android.server.NetworkStackService.NetworkStackServiceManager;
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
 import java.net.InetAddress;
+import java.nio.BufferUnderflowException;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
@@ -406,6 +415,13 @@ public class IpClient extends StateMachine {
     private static final int PROV_CHANGE_GAINED_PROVISIONING = 3;
     private static final int PROV_CHANGE_STILL_PROVISIONED = 4;
 
+    // Specific vendor OUI(3 bytes)/vendor specific type(1 byte) pattern for upstream hotspot
+    // device detection. Add new byte array pattern below in turn.
+    private static final List<byte[]> METERED_IE_PATTERN_LIST = Collections.unmodifiableList(
+            Arrays.asList(
+                    new byte[] { (byte) 0x00, (byte) 0x17, (byte) 0xf2, (byte) 0x06 }
+    ));
+
     private final State mStoppedState = new StoppedState();
     private final State mStoppingState = new StoppingState();
     private final State mClearingIpAddressesState = new ClearingIpAddressesState();
@@ -1269,16 +1285,71 @@ public class IpClient extends StateMachine {
         return (delta != PROV_CHANGE_LOST_PROVISIONING);
     }
 
+    @VisibleForTesting
+    static String removeDoubleQuotes(@NonNull String ssid) {
+        final int length = ssid.length();
+        if ((length > 1) && (ssid.charAt(0) == '"') && (ssid.charAt(length - 1) == '"')) {
+            return ssid.substring(1, length - 1);
+        }
+        return ssid;
+    }
+
+    private List<ByteBuffer> getVendorSpecificIEs(@NonNull ScanResultInfo scanResultInfo) {
+        ArrayList<ByteBuffer> vendorSpecificPayloadList = new ArrayList<>();
+        for (InformationElement ie : scanResultInfo.getInformationElements()) {
+            if (ie.getId() == VENDOR_SPECIFIC_IE_ID) {
+                vendorSpecificPayloadList.add(ie.getPayload());
+            }
+        }
+        return vendorSpecificPayloadList;
+    }
+
+    private boolean detectUpstreamHotspotFromVendorIe() {
+        if (mConfiguration.mScanResultInfo == null) return false;
+        final ScanResultInfo scanResultInfo = mConfiguration.mScanResultInfo;
+        final String ssid = scanResultInfo.getSsid();
+        final List<ByteBuffer> vendorSpecificPayloadList = getVendorSpecificIEs(scanResultInfo);
+
+        if (mConfiguration.mDisplayName == null
+                || !removeDoubleQuotes(mConfiguration.mDisplayName).equals(ssid)) {
+            return false;
+        }
+
+        for (ByteBuffer payload : vendorSpecificPayloadList) {
+            byte[] ouiAndType = new byte[4];
+            try {
+                payload.get(ouiAndType);
+            } catch (BufferUnderflowException e) {
+                Log.e(mTag, "Couldn't parse vendor specific IE, buffer underflow");
+                return false;
+            }
+            for (byte[] pattern : METERED_IE_PATTERN_LIST) {
+                if (Arrays.equals(pattern, ouiAndType)) {
+                    if (DBG) {
+                        Log.d(mTag, "detected upstream hotspot that matches OUI:"
+                                + HexDump.toHexString(ouiAndType));
+                    }
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
     private void handleIPv4Success(DhcpResults dhcpResults) {
         mDhcpResults = new DhcpResults(dhcpResults);
         final LinkProperties newLp = assembleLinkProperties();
         final int delta = setLinkProperties(newLp);
 
+        if (mDhcpResults.vendorInfo == null && detectUpstreamHotspotFromVendorIe()) {
+            mDhcpResults.vendorInfo = DhcpPacket.VENDOR_INFO_ANDROID_METERED;
+        }
+
         if (DBG) {
-            Log.d(mTag, "onNewDhcpResults(" + Objects.toString(dhcpResults) + ")");
+            Log.d(mTag, "onNewDhcpResults(" + Objects.toString(mDhcpResults) + ")");
             Log.d(mTag, "handleIPv4Success newLp{" + newLp + "}");
         }
-        mCallback.onNewDhcpResults(dhcpResults);
+        mCallback.onNewDhcpResults(mDhcpResults);
         maybeSaveNetworkToIpMemoryStore();
 
         dispatchCallback(delta, newLp);
diff --git a/src/android/net/util/ConnectivityPacketSummary.java b/src/android/net/util/ConnectivityPacketSummary.java
index 4d04911..8164c00 100644
--- a/src/android/net/util/ConnectivityPacketSummary.java
+++ b/src/android/net/util/ConnectivityPacketSummary.java
@@ -84,8 +84,8 @@ public class ConnectivityPacketSummary {
 
     /**
      * Create a string summary of a received packet.
-     * @param hwaddr MacAddress of the receiving device.
-     * @param buffer Buffer of the packet. Length is assumed to be the buffer length.
+     * @param hwaddr MacAddress of the interface sending/receiving the packet.
+     * @param buffer The packet bytes. Length is assumed to be the buffer length.
      * @return A summary of the packet.
      */
     public static String summarize(MacAddress hwaddr, byte[] buffer) {
@@ -97,8 +97,8 @@ public class ConnectivityPacketSummary {
 
     /**
      * Create a string summary of a received packet.
-     * @param macAddr MacAddress of the receiving device.
-     * @param buffer Buffer of the packet.
+     * @param macAddr MacAddress of the interface sending/receiving the packet.
+     * @param buffer The packet bytes.
      * @param length Length of the packet.
      * @return A summary of the packet.
      */
diff --git a/src/com/android/server/util/NetworkStackConstants.java b/src/com/android/server/util/NetworkStackConstants.java
index 36bac27..660f0a6 100644
--- a/src/com/android/server/util/NetworkStackConstants.java
+++ b/src/com/android/server/util/NetworkStackConstants.java
@@ -148,6 +148,14 @@ public final class NetworkStackConstants {
     public static final int INFINITE_LEASE = 0xffffffff;
     public static final int DHCP4_CLIENT_PORT = 68;
 
+    /**
+     * IEEE802.11 standard constants.
+     *
+     * See also:
+     *     - https://ieeexplore.ieee.org/document/7786995
+     */
+    public static final int VENDOR_SPECIFIC_IE_ID = 0xdd;
+
     private NetworkStackConstants() {
         throw new UnsupportedOperationException("This class is not to be instantiated");
     }
diff --git a/tests/integration/src/android/net/ip/IpClientIntegrationTest.java b/tests/integration/src/android/net/ip/IpClientIntegrationTest.java
index a60e32c..97da9fb 100644
--- a/tests/integration/src/android/net/ip/IpClientIntegrationTest.java
+++ b/tests/integration/src/android/net/ip/IpClientIntegrationTest.java
@@ -24,9 +24,11 @@ import static android.net.dhcp.DhcpPacket.DHCP_SERVER;
 import static android.net.dhcp.DhcpPacket.ENCAP_L2;
 import static android.net.dhcp.DhcpPacket.INADDR_BROADCAST;
 import static android.net.dhcp.DhcpPacket.INFINITE_LEASE;
+import static android.net.ip.IpClient.removeDoubleQuotes;
 import static android.net.ipmemorystore.Status.SUCCESS;
 import static android.net.shared.Inet4AddressUtils.getBroadcastAddress;
 import static android.net.shared.Inet4AddressUtils.getPrefixMaskAsInet4Address;
+import static android.net.shared.IpConfigurationParcelableUtil.fromStableParcelable;
 import static android.system.OsConstants.ETH_P_IPV6;
 import static android.system.OsConstants.IPPROTO_ICMPV6;
 import static android.system.OsConstants.IPPROTO_TCP;
@@ -47,6 +49,7 @@ import static com.android.server.util.NetworkStackConstants.ICMPV6_ROUTER_SOLICI
 import static com.android.server.util.NetworkStackConstants.IPV6_HEADER_LEN;
 import static com.android.server.util.NetworkStackConstants.IPV6_LEN_OFFSET;
 import static com.android.server.util.NetworkStackConstants.IPV6_PROTOCOL_OFFSET;
+import static com.android.server.util.NetworkStackConstants.VENDOR_SPECIFIC_IE_ID;
 
 import static junit.framework.Assert.fail;
 
@@ -78,6 +81,8 @@ import android.content.ContentResolver;
 import android.content.Context;
 import android.content.res.Resources;
 import android.net.ConnectivityManager;
+import android.net.DhcpResults;
+import android.net.DhcpResultsParcelable;
 import android.net.INetd;
 import android.net.InetAddresses;
 import android.net.InterfaceConfigurationParcel;
@@ -100,6 +105,7 @@ import android.net.ipmemorystore.NetworkAttributes;
 import android.net.ipmemorystore.OnNetworkAttributesRetrievedListener;
 import android.net.ipmemorystore.Status;
 import android.net.shared.ProvisioningConfiguration;
+import android.net.shared.ProvisioningConfiguration.ScanResultInfo;
 import android.net.util.InterfaceParams;
 import android.net.util.IpUtils;
 import android.net.util.NetworkStackUtils;
@@ -152,6 +158,7 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Objects;
+import java.util.Random;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.TimeUnit;
 
@@ -226,6 +233,10 @@ public class IpClientIntegrationTest {
     private static final String TEST_HOST_NAME = "AOSP on Crosshatch";
     private static final String TEST_HOST_NAME_TRANSLITERATION = "AOSP-on-Crosshatch";
     private static final String TEST_CAPTIVE_PORTAL_URL = "https://example.com/capportapi";
+    private static final byte[] TEST_HOTSPOT_OUI = new byte[] {
+            (byte) 0x00, (byte) 0x17, (byte) 0xF2
+    };
+    private static final byte TEST_VENDOR_SPECIFIC_TYPE = 0x06;
 
     private static class TapPacketReader extends PacketReader {
         private final ParcelFileDescriptor mTapFd;
@@ -549,12 +560,15 @@ public class IpClientIntegrationTest {
     private void startIpClientProvisioning(final boolean isDhcpLeaseCacheEnabled,
             final boolean shouldReplyRapidCommitAck, final boolean isPreconnectionEnabled,
             final boolean isDhcpIpConflictDetectEnabled,
-            final boolean isHostnameConfigurationEnabled, final String hostname)
+            final boolean isHostnameConfigurationEnabled, final String hostname,
+            final String displayName, final ScanResultInfo scanResultInfo)
             throws RemoteException {
         ProvisioningConfiguration.Builder builder = new ProvisioningConfiguration.Builder()
                 .withoutIpReachabilityMonitor()
                 .withoutIPv6();
         if (isPreconnectionEnabled) builder.withPreconnection();
+        if (displayName != null) builder.withDisplayName(displayName);
+        if (scanResultInfo != null) builder.withScanResultInfo(scanResultInfo);
 
         mDependencies.setDhcpLeaseCacheEnabled(isDhcpLeaseCacheEnabled);
         mDependencies.setDhcpRapidCommitEnabled(shouldReplyRapidCommitAck);
@@ -575,7 +589,8 @@ public class IpClientIntegrationTest {
             throws RemoteException {
         startIpClientProvisioning(isDhcpLeaseCacheEnabled, isDhcpRapidCommitEnabled,
                 isPreconnectionEnabled, isDhcpIpConflictDetectEnabled,
-                false /* isHostnameConfigurationEnabled */, null /* hostname */);
+                false /* isHostnameConfigurationEnabled */, null /* hostname */,
+                null /* displayName */, null /* ScanResultInfo */);
     }
 
     private void assertIpMemoryStoreNetworkAttributes(final Integer leaseTimeSec,
@@ -633,10 +648,11 @@ public class IpClientIntegrationTest {
             final boolean shouldReplyRapidCommitAck, final int mtu,
             final boolean isDhcpIpConflictDetectEnabled,
             final boolean isHostnameConfigurationEnabled, final String hostname,
-            final String captivePortalApiUrl) throws Exception {
+            final String captivePortalApiUrl, final String displayName,
+            final ScanResultInfo scanResultInfo) throws Exception {
         startIpClientProvisioning(isDhcpLeaseCacheEnabled, shouldReplyRapidCommitAck,
                 false /* isPreconnectionEnabled */, isDhcpIpConflictDetectEnabled,
-                isHostnameConfigurationEnabled, hostname);
+                isHostnameConfigurationEnabled, hostname, displayName, scanResultInfo);
         return handleDhcpPackets(isSuccessLease, leaseTimeSec, shouldReplyRapidCommitAck, mtu,
                 isDhcpIpConflictDetectEnabled, captivePortalApiUrl);
     }
@@ -693,7 +709,7 @@ public class IpClientIntegrationTest {
         return performDhcpHandshake(isSuccessLease, leaseTimeSec, isDhcpLeaseCacheEnabled,
                 isDhcpRapidCommitEnabled, mtu, isDhcpIpConflictDetectEnabled,
                 false /* isHostnameConfigurationEnabled */, null /* hostname */,
-                null /* captivePortalApiUrl */);
+                null /* captivePortalApiUrl */, null /* displayName */, null /* scanResultInfo */);
     }
 
     private DhcpPacket getNextDhcpPacket() throws ParseException {
@@ -1484,7 +1500,7 @@ public class IpClientIntegrationTest {
                 false /* isDhcpRapidCommitEnabled */, TEST_DEFAULT_MTU,
                 false /* isDhcpIpConflictDetectEnabled */,
                 true /* isHostnameConfigurationEnabled */, TEST_HOST_NAME /* hostname */,
-                null /* captivePortalApiUrl */);
+                null /* captivePortalApiUrl */, null /* displayName */, null /* scanResultInfo */);
         assertEquals(2, sentPackets.size());
         assertHostname(true, TEST_HOST_NAME, TEST_HOST_NAME_TRANSLITERATION, sentPackets);
         assertIpMemoryStoreNetworkAttributes(TEST_LEASE_DURATION_S, currentTime, TEST_DEFAULT_MTU);
@@ -1498,7 +1514,7 @@ public class IpClientIntegrationTest {
                 false /* isDhcpRapidCommitEnabled */, TEST_DEFAULT_MTU,
                 false /* isDhcpIpConflictDetectEnabled */,
                 false /* isHostnameConfigurationEnabled */, TEST_HOST_NAME,
-                null /* captivePortalApiUrl */);
+                null /* captivePortalApiUrl */, null /* displayName */, null /* scanResultInfo */);
         assertEquals(2, sentPackets.size());
         assertHostname(false, TEST_HOST_NAME, TEST_HOST_NAME_TRANSLITERATION, sentPackets);
         assertIpMemoryStoreNetworkAttributes(TEST_LEASE_DURATION_S, currentTime, TEST_DEFAULT_MTU);
@@ -1512,7 +1528,7 @@ public class IpClientIntegrationTest {
                 false /* isDhcpRapidCommitEnabled */, TEST_DEFAULT_MTU,
                 false /* isDhcpIpConflictDetectEnabled */,
                 true /* isHostnameConfigurationEnabled */, null /* hostname */,
-                null /* captivePortalApiUrl */);
+                null /* captivePortalApiUrl */, null /* displayName */, null /* scanResultInfo */);
         assertEquals(2, sentPackets.size());
         assertHostname(true, null /* hostname */, null /* hostnameAfterTransliteration */,
                 sentPackets);
@@ -1566,4 +1582,99 @@ public class IpClientIntegrationTest {
         assumeFalse(CaptivePortalDataShimImpl.isSupported());
         runDhcpClientCaptivePortalApiTest(false /* featureEnabled */, true /* serverSendsOption */);
     }
+
+    private ScanResultInfo makeScanResultInfo(final int id, final String ssid,
+            final byte[] oui, final byte type, final byte[] data) {
+        final ByteBuffer payload = ByteBuffer.allocate(4 + data.length);
+        payload.put(oui);
+        payload.put(type);
+        payload.put(data);
+        payload.flip();
+        final ScanResultInfo.InformationElement ie =
+                new ScanResultInfo.InformationElement(id /* IE id */, payload);
+        return new ScanResultInfo(ssid, Collections.singletonList(ie));
+    }
+
+    private void doUpstreamHotspotDetectionTest(final int id, final String displayName,
+            final String ssid, final byte[] oui, final byte type, final byte[] data)
+            throws Exception {
+        final ScanResultInfo info = makeScanResultInfo(id, ssid, oui, type, data);
+        final long currentTime = System.currentTimeMillis();
+        final List<DhcpPacket> sentPackets = performDhcpHandshake(true /* isSuccessLease */,
+                TEST_LEASE_DURATION_S, true /* isDhcpLeaseCacheEnabled */,
+                false /* isDhcpRapidCommitEnabled */, TEST_DEFAULT_MTU,
+                false /* isDhcpIpConflictDetectEnabled */,
+                false /* isHostnameConfigurationEnabled */, null /* hostname */,
+                null /* captivePortalApiUrl */, displayName, info /* scanResultInfo */);
+        assertEquals(2, sentPackets.size());
+
+        ArgumentCaptor<DhcpResultsParcelable> captor =
+                ArgumentCaptor.forClass(DhcpResultsParcelable.class);
+        verify(mCb, timeout(TEST_TIMEOUT_MS)).onNewDhcpResults(captor.capture());
+        DhcpResults lease = fromStableParcelable(captor.getValue());
+        assertNotNull(lease);
+        assertEquals(lease.getIpAddress().getAddress(), CLIENT_ADDR);
+        assertEquals(lease.getGateway(), SERVER_ADDR);
+        assertEquals(1, lease.getDnsServers().size());
+        assertTrue(lease.getDnsServers().contains(SERVER_ADDR));
+        assertEquals(lease.getServerAddress(), SERVER_ADDR);
+        assertEquals(lease.getMtu(), TEST_DEFAULT_MTU);
+        if (id == VENDOR_SPECIFIC_IE_ID
+                && ssid.equals(removeDoubleQuotes(displayName))
+                && Arrays.equals(oui, TEST_HOTSPOT_OUI)
+                && type == TEST_VENDOR_SPECIFIC_TYPE) {
+            assertEquals(lease.vendorInfo, DhcpPacket.VENDOR_INFO_ANDROID_METERED);
+        } else {
+            assertNull(lease.vendorInfo);
+        }
+
+        assertIpMemoryStoreNetworkAttributes(TEST_LEASE_DURATION_S, currentTime, TEST_DEFAULT_MTU);
+    }
+
+    @Test
+    public void testUpstreamHotspotDetection() throws Exception {
+        byte[] data = new byte[10];
+        new Random().nextBytes(data);
+        doUpstreamHotspotDetectionTest(0xdd, "\"ssid\"", "ssid",
+                new byte[] { (byte) 0x00, (byte) 0x17, (byte) 0xF2 }, (byte) 0x06, data);
+    }
+
+    @Test
+    public void testUpstreamHotspotDetection_incorrectIeId() throws Exception {
+        byte[] data = new byte[10];
+        new Random().nextBytes(data);
+        doUpstreamHotspotDetectionTest(0xdc, "\"ssid\"", "ssid",
+                new byte[] { (byte) 0x00, (byte) 0x17, (byte) 0xF2 }, (byte) 0x06, data);
+    }
+
+    @Test
+    public void testUpstreamHotspotDetection_incorrectOUI() throws Exception {
+        byte[] data = new byte[10];
+        new Random().nextBytes(data);
+        doUpstreamHotspotDetectionTest(0xdd, "\"ssid\"", "ssid",
+                new byte[] { (byte) 0x00, (byte) 0x1A, (byte) 0x11 }, (byte) 0x06, data);
+    }
+
+    @Test
+    public void testUpstreamHotspotDetection_incorrectSsid() throws Exception {
+        byte[] data = new byte[10];
+        new Random().nextBytes(data);
+        doUpstreamHotspotDetectionTest(0xdd, "\"another ssid\"", "ssid",
+                new byte[] { (byte) 0x00, (byte) 0x17, (byte) 0xF2 }, (byte) 0x06, data);
+    }
+
+    @Test
+    public void testUpstreamHotspotDetection_incorrectType() throws Exception {
+        byte[] data = new byte[10];
+        new Random().nextBytes(data);
+        doUpstreamHotspotDetectionTest(0xdd, "\"ssid\"", "ssid",
+                new byte[] { (byte) 0x00, (byte) 0x17, (byte) 0xF2 }, (byte) 0x0a, data);
+    }
+
+    @Test
+    public void testUpstreamHotspotDetection_zeroLengthData() throws Exception {
+        byte[] data = new byte[0];
+        doUpstreamHotspotDetectionTest(0xdd, "\"ssid\"", "ssid",
+                new byte[] { (byte) 0x00, (byte) 0x17, (byte) 0xF2 }, (byte) 0x06, data);
+    }
 }