Merge changes from topic "ipsec-tramsform-state" into main

* changes:
  Expose APIs to query the state of an IpSecTransform
  Reland "Support getting transform state in IpSecService"

framework-t/api/current.txt

@@ -127,6 +127,7 @@ package android.net {
 
   public final class IpSecTransform implements java.lang.AutoCloseable {
     method public void close();
+    method @FlaggedApi("com.android.net.flags.ipsec_transform_state") public void getIpSecTransformState(@NonNull java.util.concurrent.Executor, @NonNull android.os.OutcomeReceiver<android.net.IpSecTransformState,java.lang.RuntimeException>);
   }
 
   public static class IpSecTransform.Builder {
@@ -138,6 +139,29 @@ package android.net {
     method @NonNull public android.net.IpSecTransform.Builder setIpv4Encapsulation(@NonNull android.net.IpSecManager.UdpEncapsulationSocket, int);
   }
 
+  @FlaggedApi("com.android.net.flags.ipsec_transform_state") public final class IpSecTransformState implements android.os.Parcelable {
+    method public int describeContents();
+    method public long getByteCount();
+    method public long getPacketCount();
+    method @NonNull public byte[] getReplayBitmap();
+    method public long getRxHighestSequenceNumber();
+    method public long getTimestamp();
+    method public long getTxHighestSequenceNumber();
+    method public void writeToParcel(@NonNull android.os.Parcel, int);
+    field @NonNull public static final android.os.Parcelable.Creator<android.net.IpSecTransformState> CREATOR;
+  }
+
+  @FlaggedApi("com.android.net.flags.ipsec_transform_state") public static final class IpSecTransformState.Builder {
+    ctor public IpSecTransformState.Builder();
+    method @NonNull public android.net.IpSecTransformState build();
+    method @NonNull public android.net.IpSecTransformState.Builder setByteCount(long);
+    method @NonNull public android.net.IpSecTransformState.Builder setPacketCount(long);
+    method @NonNull public android.net.IpSecTransformState.Builder setReplayBitmap(@NonNull byte[]);
+    method @NonNull public android.net.IpSecTransformState.Builder setRxHighestSequenceNumber(long);
+    method @NonNull public android.net.IpSecTransformState.Builder setTimestamp(long);
+    method @NonNull public android.net.IpSecTransformState.Builder setTxHighestSequenceNumber(long);
+  }
+
   public class TrafficStats {
     ctor public TrafficStats();
     method public static void clearThreadStatsTag();

framework-t/src/android/net/IIpSecService.aidl

@@ -22,6 +22,7 @@ import android.net.IpSecConfig;
 import android.net.IpSecUdpEncapResponse;
 import android.net.IpSecSpiResponse;
 import android.net.IpSecTransformResponse;
+import android.net.IpSecTransformState;
 import android.net.IpSecTunnelInterfaceResponse;
 import android.os.Bundle;
 import android.os.IBinder;
@@ -74,6 +75,8 @@ interface IIpSecService
 
     void deleteTransform(int transformId);
 
+    IpSecTransformState getTransformState(int transformId);
+
     void applyTransportModeTransform(
             in ParcelFileDescriptor socket, int direction, int transformId);
 

framework-t/src/android/net/IpSecManager.java

@@ -65,6 +65,13 @@ import java.util.Objects;
 public class IpSecManager {
     private static final String TAG = "IpSecManager";
 
+    // TODO : remove this class when udc-mainline-prod is abandoned and android.net.flags.Flags is
+    // available here
+    /** @hide */
+    public static class Flags {
+        static final String IPSEC_TRANSFORM_STATE = "com.android.net.flags.ipsec_transform_state";
+    }
+
     /**
      * Feature flag to declare the kernel support of updating IPsec SAs.
      *
@@ -1084,6 +1091,12 @@ public class IpSecManager {
         }
     }
 
+    /** @hide */
+    public IpSecTransformState getTransformState(int transformId)
+            throws IllegalStateException, RemoteException {
+        return mService.getTransformState(transformId);
+    }
+
     /**
      * Construct an instance of IpSecManager within an application context.
      *

framework-t/src/android/net/IpSecTransform.java

@@ -15,8 +15,11 @@
  */
 package android.net;
 
+import static android.net.IpSecManager.Flags.IPSEC_TRANSFORM_STATE;
 import static android.net.IpSecManager.INVALID_RESOURCE_ID;
 
+import android.annotation.CallbackExecutor;
+import android.annotation.FlaggedApi;
 import android.annotation.IntDef;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
@@ -26,6 +29,8 @@ import android.annotation.SystemApi;
 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.os.Binder;
+import android.os.OutcomeReceiver;
+import android.os.RemoteException;
 import android.os.ServiceSpecificException;
 import android.util.Log;
 
@@ -38,6 +43,7 @@ import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.net.InetAddress;
 import java.util.Objects;
+import java.util.concurrent.Executor;
 
 /**
  * This class represents a transform, which roughly corresponds to an IPsec Security Association.
@@ -200,6 +206,43 @@ public final class IpSecTransform implements AutoCloseable {
         return mResourceId;
     }
 
+    /**
+     * Retrieve the current state of this IpSecTransform.
+     *
+     * @param executor The {@link Executor} on which to call the supplied callback.
+     * @param callback Callback that's called after the transform state is ready or when an error
+     *     occurs.
+     * @see IpSecTransformState
+     */
+    @FlaggedApi(IPSEC_TRANSFORM_STATE)
+    public void getIpSecTransformState(
+            @CallbackExecutor @NonNull Executor executor,
+            @NonNull OutcomeReceiver<IpSecTransformState, RuntimeException> callback) {
+        Objects.requireNonNull(executor);
+        Objects.requireNonNull(callback);
+
+        // TODO: Consider adding check to prevent DDoS attack.
+
+        try {
+            final IpSecTransformState ipSecTransformState =
+                    getIpSecManager(mContext).getTransformState(mResourceId);
+            executor.execute(
+                    () -> {
+                        callback.onResult(ipSecTransformState);
+                    });
+        } catch (IllegalStateException e) {
+            executor.execute(
+                    () -> {
+                        callback.onError(e);
+                    });
+        } catch (RemoteException e) {
+            executor.execute(
+                    () -> {
+                        callback.onError(e.rethrowFromSystemServer());
+                    });
+        }
+    }
+
     /**
      * A callback class to provide status information regarding a NAT-T keepalive session
      *

framework-t/src/android/net/IpSecTransformState.aidl

+/*
+ * Copyright (C) 2023 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;
+
+/** @hide */
+parcelable IpSecTransformState;
\ No newline at end of file

framework-t/src/android/net/IpSecTransformState.java

+/*
+ * Copyright (C) 2023 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 android.net.IpSecManager.Flags.IPSEC_TRANSFORM_STATE;
+
+import static com.android.internal.annotations.VisibleForTesting.Visibility;
+
+import android.annotation.FlaggedApi;
+import android.annotation.NonNull;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.net.module.util.HexDump;
+
+import java.util.Objects;
+
+/**
+ * This class represents a snapshot of the state of an IpSecTransform
+ *
+ * <p>This class provides the current state of an IpSecTransform, enabling link metric analysis by
+ * the caller. Use cases include understanding transform usage, such as packet and byte counts, as
+ * well as observing out-of-order delivery by checking the bitmap. Additionally, callers can query
+ * IpSecTransformStates at two timestamps. By comparing the changes in packet counts and sequence
+ * numbers, callers can estimate IPsec data loss in the inbound direction.
+ */
+@FlaggedApi(IPSEC_TRANSFORM_STATE)
+public final class IpSecTransformState implements Parcelable {
+    private final long mTimeStamp;
+    private final long mTxHighestSequenceNumber;
+    private final long mRxHighestSequenceNumber;
+    private final long mPacketCount;
+    private final long mByteCount;
+    private final byte[] mReplayBitmap;
+
+    private IpSecTransformState(
+            long timestamp,
+            long txHighestSequenceNumber,
+            long rxHighestSequenceNumber,
+            long packetCount,
+            long byteCount,
+            byte[] replayBitmap) {
+        mTimeStamp = timestamp;
+        mTxHighestSequenceNumber = txHighestSequenceNumber;
+        mRxHighestSequenceNumber = rxHighestSequenceNumber;
+        mPacketCount = packetCount;
+        mByteCount = byteCount;
+
+        Objects.requireNonNull(replayBitmap, "replayBitmap is null");
+        mReplayBitmap = replayBitmap.clone();
+
+        validate();
+    }
+
+    private void validate() {
+        Objects.requireNonNull(mReplayBitmap, "mReplayBitmap is null");
+    }
+
+    /**
+     * Deserializes a IpSecTransformState from a PersistableBundle.
+     *
+     * @hide
+     */
+    @VisibleForTesting(visibility = Visibility.PRIVATE)
+    public IpSecTransformState(@NonNull Parcel in) {
+        Objects.requireNonNull(in, "The input PersistableBundle is null");
+        mTimeStamp = in.readLong();
+        mTxHighestSequenceNumber = in.readLong();
+        mRxHighestSequenceNumber = in.readLong();
+        mPacketCount = in.readLong();
+        mByteCount = in.readLong();
+        mReplayBitmap = HexDump.hexStringToByteArray(in.readString());
+
+        validate();
+    }
+
+    // Parcelable methods
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel out, int flags) {
+        out.writeLong(mTimeStamp);
+        out.writeLong(mTxHighestSequenceNumber);
+        out.writeLong(mRxHighestSequenceNumber);
+        out.writeLong(mPacketCount);
+        out.writeLong(mByteCount);
+        out.writeString(HexDump.toHexString(mReplayBitmap));
+    }
+
+    @NonNull
+    public static final Parcelable.Creator<IpSecTransformState> CREATOR =
+            new Parcelable.Creator<IpSecTransformState>() {
+                @NonNull
+                public IpSecTransformState createFromParcel(Parcel in) {
+                    return new IpSecTransformState(in);
+                }
+
+                @NonNull
+                public IpSecTransformState[] newArray(int size) {
+                    return new IpSecTransformState[size];
+                }
+            };
+
+    /**
+     * Retrieve the epoch timestamp (milliseconds) for when this state was created
+     *
+     * @see Builder#setTimestamp(long)
+     */
+    public long getTimestamp() {
+        return mTimeStamp;
+    }
+
+    /**
+     * Retrieve the highest sequence number sent so far
+     *
+     * @see Builder#setTxHighestSequenceNumber(long)
+     */
+    public long getTxHighestSequenceNumber() {
+        return mTxHighestSequenceNumber;
+    }
+
+    /**
+     * Retrieve the highest sequence number received so far
+     *
+     * @see Builder#setRxHighestSequenceNumber(long)
+     */
+    public long getRxHighestSequenceNumber() {
+        return mRxHighestSequenceNumber;
+    }
+
+    /**
+     * Retrieve the number of packets received AND sent so far
+     *
+     * @see Builder#setPacketCount(long)
+     */
+    public long getPacketCount() {
+        return mPacketCount;
+    }
+
+    /**
+     * Retrieve the number of bytes received AND sent so far
+     *
+     * @see Builder#setByteCount(long)
+     */
+    public long getByteCount() {
+        return mByteCount;
+    }
+
+    /**
+     * Retrieve the replay bitmap
+     *
+     * <p>This bitmap represents a replay window, allowing the caller to observe out-of-order
+     * delivery. The last bit represents the highest sequence number received so far and bits for
+     * the received packets will be marked as true.
+     *
+     * <p>The size of a replay bitmap will never change over the lifetime of an IpSecTransform
+     *
+     * <p>The replay bitmap is solely useful for inbound IpSecTransforms. For outbound
+     * IpSecTransforms, all bits will be unchecked.
+     *
+     * @see Builder#setReplayBitmap(byte[])
+     */
+    @NonNull
+    public byte[] getReplayBitmap() {
+        return mReplayBitmap.clone();
+    }
+
+    /** Builder class for testing purposes */
+    @FlaggedApi(IPSEC_TRANSFORM_STATE)
+    public static final class Builder {
+        private long mTimeStamp;
+        private long mTxHighestSequenceNumber;
+        private long mRxHighestSequenceNumber;
+        private long mPacketCount;
+        private long mByteCount;
+        private byte[] mReplayBitmap;
+
+        public Builder() {
+            mTimeStamp = System.currentTimeMillis();
+        }
+
+        /**
+         * Set the epoch timestamp (milliseconds) for when this state was created
+         *
+         * @see IpSecTransformState#getTimestamp()
+         */
+        @NonNull
+        public Builder setTimestamp(long timeStamp) {
+            mTimeStamp = timeStamp;
+            return this;
+        }
+
+        /**
+         * Set the highest sequence number sent so far
+         *
+         * @see IpSecTransformState#getTxHighestSequenceNumber()
+         */
+        @NonNull
+        public Builder setTxHighestSequenceNumber(long seqNum) {
+            mTxHighestSequenceNumber = seqNum;
+            return this;
+        }
+
+        /**
+         * Set the highest sequence number received so far
+         *
+         * @see IpSecTransformState#getRxHighestSequenceNumber()
+         */
+        @NonNull
+        public Builder setRxHighestSequenceNumber(long seqNum) {
+            mRxHighestSequenceNumber = seqNum;
+            return this;
+        }
+
+        /**
+         * Set the number of packets received AND sent so far
+         *
+         * @see IpSecTransformState#getPacketCount()
+         */
+        @NonNull
+        public Builder setPacketCount(long packetCount) {
+            mPacketCount = packetCount;
+            return this;
+        }
+
+        /**
+         * Set the number of bytes received AND sent so far
+         *
+         * @see IpSecTransformState#getByteCount()
+         */
+        @NonNull
+        public Builder setByteCount(long byteCount) {
+            mByteCount = byteCount;
+            return this;
+        }
+
+        /**
+         * Set the replay bitmap
+         *
+         * @see IpSecTransformState#getReplayBitmap()
+         */
+        @NonNull
+        public Builder setReplayBitmap(@NonNull byte[] bitMap) {
+            mReplayBitmap = bitMap.clone();
+            return this;
+        }
+
+        /**
+         * Build and validate the IpSecTransformState
+         *
+         * @return an immutable IpSecTransformState instance
+         */
+        @NonNull
+        public IpSecTransformState build() {
+            return new IpSecTransformState(
+                    mTimeStamp,
+                    mTxHighestSequenceNumber,
+                    mRxHighestSequenceNumber,
+                    mPacketCount,
+                    mByteCount,
+                    mReplayBitmap);
+        }
+    }
+}

service-t/src/com/android/server/IpSecService.java

@@ -42,6 +42,7 @@ import android.net.IpSecMigrateInfoParcel;
 import android.net.IpSecSpiResponse;
 import android.net.IpSecTransform;
 import android.net.IpSecTransformResponse;
+import android.net.IpSecTransformState;
 import android.net.IpSecTunnelInterfaceResponse;
 import android.net.IpSecUdpEncapResponse;
 import android.net.LinkAddress;
@@ -70,6 +71,7 @@ import com.android.modules.utils.build.SdkLevel;
 import com.android.net.module.util.BinderUtils;
 import com.android.net.module.util.NetdUtils;
 import com.android.net.module.util.PermissionUtils;
+import com.android.net.module.util.netlink.xfrm.XfrmNetlinkNewSaMessage;
 
 import libcore.io.IoUtils;
 
@@ -109,6 +111,7 @@ public class IpSecService extends IIpSecService.Stub {
     @VisibleForTesting static final int MAX_PORT_BIND_ATTEMPTS = 10;
 
     private final INetd mNetd;
+    private final IpSecXfrmController mIpSecXfrmCtrl;
 
     static {
         try {
@@ -152,6 +155,11 @@ public class IpSecService extends IIpSecService.Stub {
             }
             return netd;
         }
+
+        /** Get a instance of IpSecXfrmController */
+        public IpSecXfrmController getIpSecXfrmController() {
+            return new IpSecXfrmController();
+        }
     }
 
     final UidFdTagger mUidFdTagger;
@@ -1111,6 +1119,7 @@ public class IpSecService extends IIpSecService.Stub {
         mContext = context;
         mDeps = Objects.requireNonNull(deps, "Missing dependencies.");
         mUidFdTagger = uidFdTagger;
+        mIpSecXfrmCtrl = mDeps.getIpSecXfrmController();
         try {
             mNetd = mDeps.getNetdInstance(mContext);
         } catch (RemoteException e) {
@@ -1862,6 +1871,48 @@ public class IpSecService extends IIpSecService.Stub {
         releaseResource(userRecord.mTransformRecords, resourceId);
     }
 
+    @Override
+    public synchronized IpSecTransformState getTransformState(int transformId)
+            throws IllegalStateException, RemoteException {
+        mContext.enforceCallingOrSelfPermission(
+                android.Manifest.permission.ACCESS_NETWORK_STATE, "IpsecService#getTransformState");
+
+        UserRecord userRecord = mUserResourceTracker.getUserRecord(Binder.getCallingUid());
+        TransformRecord transformInfo =
+                userRecord.mTransformRecords.getResourceOrThrow(transformId);
+
+        final int spi = transformInfo.getSpiRecord().getSpi();
+        final InetAddress destAddress =
+                InetAddresses.parseNumericAddress(
+                        transformInfo.getConfig().getDestinationAddress());
+        Log.d(TAG, "getTransformState for spi " + spi + " destAddress " + destAddress);
+
+        // Make netlink call
+        final XfrmNetlinkNewSaMessage xfrmNewSaMsg;
+        try {
+            xfrmNewSaMsg = mIpSecXfrmCtrl.ipSecGetSa(destAddress, Integer.toUnsignedLong(spi));
+        } catch (ErrnoException | IOException e) {
+            Log.e(TAG, "getTransformState: failed to get IpSecTransformState" + e.toString());
+            throw new IllegalStateException("Failed to get IpSecTransformState", e);
+        }
+
+        // Keep the netlink socket open to save time for the next call. It is cheap to have a
+        // persistent netlink socket in the system server
+
+        if (xfrmNewSaMsg == null) {
+            Log.e(TAG, "getTransformState: failed to get IpSecTransformState xfrmNewSaMsg is null");
+            throw new IllegalStateException("Failed to get IpSecTransformState");
+        }
+
+        return new IpSecTransformState.Builder()
+                .setTxHighestSequenceNumber(xfrmNewSaMsg.getTxSequenceNumber())
+                .setRxHighestSequenceNumber(xfrmNewSaMsg.getRxSequenceNumber())
+                .setPacketCount(xfrmNewSaMsg.getPacketCount())
+                .setByteCount(xfrmNewSaMsg.getByteCount())
+                .setReplayBitmap(xfrmNewSaMsg.getBitmap())
+                .build();
+    }
+
     /**
      * Apply an active transport mode transform to a socket, which will apply the IPsec security
      * association as a correspondent policy to the provided socket

tests/unit/java/com/android/server/IpSecServiceParameterizedTest.java

@@ -33,6 +33,7 @@ import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.anyLong;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.argThat;
 import static org.mockito.ArgumentMatchers.eq;
@@ -74,6 +75,7 @@ import android.util.ArraySet;
 
 import androidx.test.filters.SmallTest;
 
+import com.android.net.module.util.netlink.xfrm.XfrmNetlinkNewSaMessage;
 import com.android.server.IpSecService.TunnelInterfaceRecord;
 import com.android.testutils.DevSdkIgnoreRule;
 
@@ -85,6 +87,7 @@ import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
 import java.net.Inet4Address;
+import java.net.InetAddress;
 import java.net.Socket;
 import java.util.Arrays;
 import java.util.Collection;
@@ -149,6 +152,7 @@ public class IpSecServiceParameterizedTest {
         private Set<String> mAllowedPermissions = new ArraySet<>(Arrays.asList(
                 android.Manifest.permission.MANAGE_IPSEC_TUNNELS,
                 android.Manifest.permission.NETWORK_STACK,
+                android.Manifest.permission.ACCESS_NETWORK_STATE,
                 PERMISSION_MAINLINE_NETWORK_STACK));
 
         private void setAllowedPermissions(String... permissions) {
@@ -202,11 +206,13 @@ public class IpSecServiceParameterizedTest {
     private IpSecService.Dependencies makeDependencies() throws RemoteException {
         final IpSecService.Dependencies deps = mock(IpSecService.Dependencies.class);
         when(deps.getNetdInstance(mTestContext)).thenReturn(mMockNetd);
+        when(deps.getIpSecXfrmController()).thenReturn(mMockXfrmCtrl);
         return deps;
     }
 
     INetd mMockNetd;
     PackageManager mMockPkgMgr;
+    IpSecXfrmController mMockXfrmCtrl;
     IpSecService.Dependencies mDeps;
     IpSecService mIpSecService;
     Network fakeNetwork = new Network(0xAB);
@@ -235,6 +241,7 @@ public class IpSecServiceParameterizedTest {
     @Before
     public void setUp() throws Exception {
         mMockNetd = mock(INetd.class);
+        mMockXfrmCtrl = mock(IpSecXfrmController.class);
         mMockPkgMgr = mock(PackageManager.class);
         mDeps = makeDependencies();
         mIpSecService = new IpSecService(mTestContext, mDeps);
@@ -505,6 +512,32 @@ public class IpSecServiceParameterizedTest {
         }
     }
 
+    @Test
+    public void getTransformState() throws Exception {
+        XfrmNetlinkNewSaMessage mockXfrmNewSaMsg = mock(XfrmNetlinkNewSaMessage.class);
+        when(mockXfrmNewSaMsg.getBitmap()).thenReturn(new byte[512]);
+        when(mMockXfrmCtrl.ipSecGetSa(any(InetAddress.class), anyLong()))
+                .thenReturn(mockXfrmNewSaMsg);
+
+        // Create transform
+        IpSecConfig ipSecConfig = new IpSecConfig();
+        addDefaultSpisAndRemoteAddrToIpSecConfig(ipSecConfig);
+        addAuthAndCryptToIpSecConfig(ipSecConfig);
+
+        IpSecTransformResponse createTransformResp =
+                mIpSecService.createTransform(ipSecConfig, new Binder(), BLESSED_PACKAGE);
+        assertEquals(IpSecManager.Status.OK, createTransformResp.status);
+
+        // Get transform state
+        mIpSecService.getTransformState(createTransformResp.resourceId);
+
+        // Verifications
+        verify(mMockXfrmCtrl)
+                .ipSecGetSa(
+                        eq(InetAddresses.parseNumericAddress(mDestinationAddr)),
+                        eq(Integer.toUnsignedLong(TEST_SPI)));
+    }
+
     @Test
     public void testReleaseOwnedSpi() throws Exception {
         IpSecConfig ipSecConfig = new IpSecConfig();