From fc7cad313d57663b940c1f755a2c3c9b02ba0a2b Mon Sep 17 00:00:00 2001 From: Cody Kesting Date: Tue, 7 Apr 2020 16:07:33 -0700 Subject: [PATCH] Set owner and administrator UIDs for test networks. This change sets the owner and administrator UIDs for test networks when their initial values match the UID for the app creating the test network. This ensures that apps registering test networks can only make themselves owners / administrators of the network. Bug: 153449964 Test: atest NetworkAgentTest Change-Id: I3a974700aa1d83cb285295ed1de0aa263e2e5b58 --- .../java/android/net/NetworkCapabilities.java | 13 ++++- .../android/server/ConnectivityService.java | 6 +- .../android/server/TestNetworkService.java | 57 +++++++++---------- .../server/connectivity/NetworkAgentInfo.java | 7 ++- .../server/ConnectivityServiceTest.java | 13 +++-- .../connectivity/LingerMonitorTest.java | 3 +- 6 files changed, 56 insertions(+), 43 deletions(-) diff --git a/core/java/android/net/NetworkCapabilities.java b/core/java/android/net/NetworkCapabilities.java index fea3245784..4a9c824efa 100644 --- a/core/java/android/net/NetworkCapabilities.java +++ b/core/java/android/net/NetworkCapabilities.java @@ -666,16 +666,27 @@ public final class NetworkCapabilities implements Parcelable { * restrictions. * @hide */ - public void restrictCapabilitesForTestNetwork() { + public void restrictCapabilitesForTestNetwork(int creatorUid) { final long originalCapabilities = mNetworkCapabilities; final NetworkSpecifier originalSpecifier = mNetworkSpecifier; final int originalSignalStrength = mSignalStrength; + final int originalOwnerUid = getOwnerUid(); + final int[] originalAdministratorUids = getAdministratorUids(); clearAll(); // Reset the transports to only contain TRANSPORT_TEST. mTransportTypes = (1 << TRANSPORT_TEST); mNetworkCapabilities = originalCapabilities & TEST_NETWORKS_ALLOWED_CAPABILITIES; mNetworkSpecifier = originalSpecifier; mSignalStrength = originalSignalStrength; + + // Only retain the owner and administrator UIDs if they match the app registering the remote + // caller that registered the network. + if (originalOwnerUid == creatorUid) { + setOwnerUid(creatorUid); + } + if (ArrayUtils.contains(originalAdministratorUids, creatorUid)) { + setAdministratorUids(new int[] {creatorUid}); + } } /** diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java index 58e06e00ef..615895ae5d 100644 --- a/services/core/java/com/android/server/ConnectivityService.java +++ b/services/core/java/com/android/server/ConnectivityService.java @@ -2732,7 +2732,7 @@ public class ConnectivityService extends IConnectivityManager.Stub // the Messenger, but if this ever changes, not making a defensive copy // here will give attack vectors to clients using this code path. networkCapabilities = new NetworkCapabilities(networkCapabilities); - networkCapabilities.restrictCapabilitesForTestNetwork(); + networkCapabilities.restrictCapabilitesForTestNetwork(nai.creatorUid); } updateCapabilities(nai.getCurrentScore(), nai, networkCapabilities); break; @@ -5855,7 +5855,7 @@ public class ConnectivityService extends IConnectivityManager.Stub // the call to mixInCapabilities below anyway, but sanitizing here means the NAI never // sees capabilities that may be malicious, which might prevent mistakes in the future. networkCapabilities = new NetworkCapabilities(networkCapabilities); - networkCapabilities.restrictCapabilitesForTestNetwork(); + networkCapabilities.restrictCapabilitesForTestNetwork(Binder.getCallingUid()); } else { enforceNetworkFactoryPermission(); } @@ -5868,7 +5868,7 @@ public class ConnectivityService extends IConnectivityManager.Stub final NetworkAgentInfo nai = new NetworkAgentInfo(messenger, new AsyncChannel(), new Network(mNetIdManager.reserveNetId()), new NetworkInfo(networkInfo), lp, nc, currentScore, mContext, mTrackerHandler, new NetworkAgentConfig(networkAgentConfig), - this, mNetd, mDnsResolver, mNMS, providerId); + this, mNetd, mDnsResolver, mNMS, providerId, Binder.getCallingUid()); // Make sure the LinkProperties and NetworkCapabilities reflect what the agent info says. nai.getAndSetNetworkCapabilities(mixInCapabilities(nai, nc)); diff --git a/services/core/java/com/android/server/TestNetworkService.java b/services/core/java/com/android/server/TestNetworkService.java index 0ea73460e1..d6bd5a1d7c 100644 --- a/services/core/java/com/android/server/TestNetworkService.java +++ b/services/core/java/com/android/server/TestNetworkService.java @@ -317,39 +317,34 @@ class TestNetworkService extends ITestNetworkManager.Stub { "Cannot create network for non ipsec, non-testtun interface"); } - // Setup needs to be done with NETWORK_STACK privileges. - int callingUid = Binder.getCallingUid(); - Binder.withCleanCallingIdentity( - () -> { - try { - mNMS.setInterfaceUp(iface); + try { + // This requires NETWORK_STACK privileges. + Binder.withCleanCallingIdentity(() -> mNMS.setInterfaceUp(iface)); - // Synchronize all accesses to mTestNetworkTracker to prevent the case - // where: - // 1. TestNetworkAgent successfully binds to death of binder - // 2. Before it is added to the mTestNetworkTracker, binder dies, - // binderDied() is called (on a different thread) - // 3. This thread is pre-empted, put() is called after remove() - synchronized (mTestNetworkTracker) { - TestNetworkAgent agent = - registerTestNetworkAgent( - mHandler.getLooper(), - mContext, - iface, - lp, - isMetered, - callingUid, - administratorUids, - binder); + // Synchronize all accesses to mTestNetworkTracker to prevent the case where: + // 1. TestNetworkAgent successfully binds to death of binder + // 2. Before it is added to the mTestNetworkTracker, binder dies, binderDied() is called + // (on a different thread) + // 3. This thread is pre-empted, put() is called after remove() + synchronized (mTestNetworkTracker) { + TestNetworkAgent agent = + registerTestNetworkAgent( + mHandler.getLooper(), + mContext, + iface, + lp, + isMetered, + Binder.getCallingUid(), + administratorUids, + binder); - mTestNetworkTracker.put(agent.getNetwork().netId, agent); - } - } catch (SocketException e) { - throw new UncheckedIOException(e); - } catch (RemoteException e) { - throw e.rethrowFromSystemServer(); - } - }); + mTestNetworkTracker.put(agent.getNetwork().netId, agent); + } + } catch (SocketException e) { + throw new UncheckedIOException(e); + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } } /** Teardown a test network */ diff --git a/services/core/java/com/android/server/connectivity/NetworkAgentInfo.java b/services/core/java/com/android/server/connectivity/NetworkAgentInfo.java index 2d1f553ab8..a9f62d9159 100644 --- a/services/core/java/com/android/server/connectivity/NetworkAgentInfo.java +++ b/services/core/java/com/android/server/connectivity/NetworkAgentInfo.java @@ -168,6 +168,9 @@ public class NetworkAgentInfo implements Comparable { // Obtained by ConnectivityService and merged into NetworkAgent-provided information. public CaptivePortalData captivePortalData; + // The UID of the remote entity that created this Network. + public final int creatorUid; + // Networks are lingered when they become unneeded as a result of their NetworkRequests being // satisfied by a higher-scoring network. so as to allow communication to wrap up before the // network is taken down. This usually only happens to the default network. Lingering ends with @@ -268,7 +271,8 @@ public class NetworkAgentInfo implements Comparable { public NetworkAgentInfo(Messenger messenger, AsyncChannel ac, Network net, NetworkInfo info, LinkProperties lp, NetworkCapabilities nc, int score, Context context, Handler handler, NetworkAgentConfig config, ConnectivityService connService, INetd netd, - IDnsResolver dnsResolver, INetworkManagementService nms, int factorySerialNumber) { + IDnsResolver dnsResolver, INetworkManagementService nms, int factorySerialNumber, + int creatorUid) { this.messenger = messenger; asyncChannel = ac; network = net; @@ -282,6 +286,7 @@ public class NetworkAgentInfo implements Comparable { mHandler = handler; networkAgentConfig = config; this.factorySerialNumber = factorySerialNumber; + this.creatorUid = creatorUid; } /** diff --git a/tests/net/java/com/android/server/ConnectivityServiceTest.java b/tests/net/java/com/android/server/ConnectivityServiceTest.java index 656fe489d8..8d3356e0be 100644 --- a/tests/net/java/com/android/server/ConnectivityServiceTest.java +++ b/tests/net/java/com/android/server/ConnectivityServiceTest.java @@ -75,6 +75,7 @@ import static android.net.NetworkPolicyManager.RULE_NONE; import static android.net.NetworkPolicyManager.RULE_REJECT_ALL; import static android.net.NetworkPolicyManager.RULE_REJECT_METERED; import static android.net.RouteInfo.RTN_UNREACHABLE; +import static android.os.Process.INVALID_UID; import static android.system.OsConstants.IPPROTO_TCP; import static com.android.server.ConnectivityServiceTestUtilsKt.transportToLegacyType; @@ -6953,7 +6954,7 @@ public class ConnectivityServiceTest { final NetworkAgentInfo naiWithoutUid = new NetworkAgentInfo( null, null, null, null, null, new NetworkCapabilities(), 0, - mServiceContext, null, null, mService, null, null, null, 0); + mServiceContext, null, null, mService, null, null, null, 0, INVALID_UID); mServiceContext.setPermission( android.Manifest.permission.NETWORK_STACK, PERMISSION_GRANTED); @@ -6969,7 +6970,7 @@ public class ConnectivityServiceTest { final NetworkAgentInfo naiWithoutUid = new NetworkAgentInfo( null, null, null, null, null, new NetworkCapabilities(), 0, - mServiceContext, null, null, mService, null, null, null, 0); + mServiceContext, null, null, mService, null, null, null, 0, INVALID_UID); mServiceContext.setPermission(android.Manifest.permission.NETWORK_STACK, PERMISSION_DENIED); @@ -6985,7 +6986,7 @@ public class ConnectivityServiceTest { final NetworkAgentInfo naiWithoutUid = new NetworkAgentInfo( null, null, null, null, null, new NetworkCapabilities(), 0, - mServiceContext, null, null, mService, null, null, null, 0); + mServiceContext, null, null, mService, null, null, null, 0, INVALID_UID); mServiceContext.setPermission(android.Manifest.permission.NETWORK_STACK, PERMISSION_DENIED); @@ -7002,7 +7003,7 @@ public class ConnectivityServiceTest { final NetworkAgentInfo naiWithoutUid = new NetworkAgentInfo( null, null, network, null, null, new NetworkCapabilities(), 0, - mServiceContext, null, null, mService, null, null, null, 0); + mServiceContext, null, null, mService, null, null, null, 0, INVALID_UID); setupLocationPermissions(Build.VERSION_CODES.Q, true, AppOpsManager.OPSTR_FINE_LOCATION, Manifest.permission.ACCESS_FINE_LOCATION); @@ -7036,7 +7037,7 @@ public class ConnectivityServiceTest { final NetworkAgentInfo naiWithUid = new NetworkAgentInfo( null, null, null, null, null, nc, 0, mServiceContext, null, null, - mService, null, null, null, 0); + mService, null, null, null, 0, INVALID_UID); setupLocationPermissions(Build.VERSION_CODES.Q, true, AppOpsManager.OPSTR_FINE_LOCATION, Manifest.permission.ACCESS_FINE_LOCATION); @@ -7058,7 +7059,7 @@ public class ConnectivityServiceTest { final NetworkAgentInfo naiWithUid = new NetworkAgentInfo( null, null, null, null, null, nc, 0, mServiceContext, null, null, - mService, null, null, null, 0); + mService, null, null, null, 0, INVALID_UID); setupLocationPermissions(Build.VERSION_CODES.Q, true, AppOpsManager.OPSTR_FINE_LOCATION, Manifest.permission.ACCESS_FINE_LOCATION); diff --git a/tests/net/java/com/android/server/connectivity/LingerMonitorTest.java b/tests/net/java/com/android/server/connectivity/LingerMonitorTest.java index 24a8717722..aafa18a532 100644 --- a/tests/net/java/com/android/server/connectivity/LingerMonitorTest.java +++ b/tests/net/java/com/android/server/connectivity/LingerMonitorTest.java @@ -38,6 +38,7 @@ import android.net.Network; import android.net.NetworkCapabilities; import android.net.NetworkInfo; import android.net.NetworkProvider; +import android.os.Binder; import android.os.INetworkManagementService; import android.text.format.DateUtils; @@ -354,7 +355,7 @@ public class LingerMonitorTest { caps.addTransportType(transport); NetworkAgentInfo nai = new NetworkAgentInfo(null, null, new Network(netId), info, null, caps, 50, mCtx, null, null /* config */, mConnService, mNetd, mDnsResolver, mNMS, - NetworkProvider.ID_NONE); + NetworkProvider.ID_NONE, Binder.getCallingUid()); nai.everValidated = true; return nai; }