[CLATJ#32] ClatCoordinator: untag clat raw socket

Untag clat raw socket while stopping clatd.

Bug: 218407445
Test: atest FrameworksNetTests
Test: connect and disconnect to/from IPv6 only network
Check dumpsys tag map and logging for tagging/untagging socket
03-04 16:29:17.247  1330  1714 I jniClatCoordinator: tag uid AID_CLAT to socket fd 420, cookie 16524
03-04 16:29:31.343  1330  1714 I jniClatCoordinator: untag socket cookie 16524

Change-Id: Id5f5bdfc97a15abfa1a49b06dcb3c2c25743c74f
diff --git a/service/jni/com_android_server_connectivity_ClatCoordinator.cpp b/service/jni/com_android_server_connectivity_ClatCoordinator.cpp
index 5be8307..4517b5c 100644
--- a/service/jni/com_android_server_connectivity_ClatCoordinator.cpp
+++ b/service/jni/com_android_server_connectivity_ClatCoordinator.cpp
@@ -514,6 +514,36 @@
     return static_cast<jlong>(sock_cookie);
 }
 
+static void com_android_server_connectivity_ClatCoordinator_untagSocket(JNIEnv* env, jobject clazz,
+                                                                        jlong cookie) {
+    uint64_t sock_cookie = static_cast<uint64_t>(cookie);
+    if (sock_cookie == bpf::NONEXISTENT_COOKIE) {
+        jniThrowExceptionFmt(env, "java/io/IOException", "Invalid socket cookie");
+        return;
+    }
+
+    // The reason that deleting entry from cookie tag map directly is that the tag socket destroy
+    // listener only monitors on group INET_TCP, INET_UDP, INET6_TCP, INET6_UDP. The other socket
+    // types, ex: raw, are not able to be removed automatically by the listener.
+    // See TrafficController::makeSkDestroyListener.
+    bpf::BpfMap<uint64_t, UidTagValue> cookieTagMap;
+    auto res = cookieTagMap.init(COOKIE_TAG_MAP_PATH);
+    if (!res.ok()) {
+        throwIOException(env, "failed to init the cookieTagMap", res.error().code());
+        return;
+    }
+
+    res = cookieTagMap.deleteValue(sock_cookie);
+    if (!res.ok()) {
+        jniThrowExceptionFmt(env, "java/io/IOException", "Failed to untag the socket: %s",
+                             strerror(res.error().code()));
+        return;
+    }
+
+    ALOGI("untag socket cookie %" PRIu64 "", sock_cookie);
+    return;
+}
+
 /*
  * JNI registration.
  */
@@ -545,6 +575,8 @@
          (void*)com_android_server_connectivity_ClatCoordinator_stopClatd},
         {"native_tagSocketAsClat", "(Ljava/io/FileDescriptor;)J",
          (void*)com_android_server_connectivity_ClatCoordinator_tagSocketAsClat},
+        {"native_untagSocket", "(J)V",
+         (void*)com_android_server_connectivity_ClatCoordinator_untagSocket},
 };
 
 int register_com_android_server_connectivity_ClatCoordinator(JNIEnv* env) {
diff --git a/service/src/com/android/server/connectivity/ClatCoordinator.java b/service/src/com/android/server/connectivity/ClatCoordinator.java
index f8d5a28..c1a8195 100644
--- a/service/src/com/android/server/connectivity/ClatCoordinator.java
+++ b/service/src/com/android/server/connectivity/ClatCoordinator.java
@@ -194,6 +194,13 @@
         public long tagSocketAsClat(@NonNull FileDescriptor sock) throws IOException {
             return native_tagSocketAsClat(sock);
         }
+
+        /**
+         * Untag socket.
+         */
+        public void untagSocket(long cookie) throws IOException {
+            native_untagSocket(cookie);
+        }
     }
 
     @VisibleForTesting
@@ -375,7 +382,7 @@
             mXlatLocalAddress6 = v6;
             mCookie = cookie;
         } catch (IOException e) {
-            // TODO: untag socket.
+            mDeps.untagSocket(cookie);
             throw new IOException("Error start clatd on " + iface + ": " + e);
         } finally {
             tunFd.close();
@@ -396,7 +403,7 @@
         Log.i(TAG, "Stopping clatd pid=" + mPid + " on " + mIface);
 
         mDeps.stopClatd(mIface, mNat64Prefix, mXlatLocalAddress4, mXlatLocalAddress6, mPid);
-        // TODO: remove setIptablesDropRule
+        mDeps.untagSocket(mCookie);
 
         Log.i(TAG, "clatd on " + mIface + " stopped");
 
@@ -405,6 +412,7 @@
         mXlatLocalAddress4 = null;
         mXlatLocalAddress6 = null;
         mPid = INVALID_PID;
+        mCookie = INVALID_COOKIE;
     }
 
     private static native String native_selectIpv4Address(String v4addr, int prefixlen)
@@ -426,4 +434,5 @@
     private static native void native_stopClatd(String iface, String pfx96, String v4, String v6,
             int pid) throws IOException;
     private static native long native_tagSocketAsClat(FileDescriptor sock) throws IOException;
+    private static native void native_untagSocket(long cookie) throws IOException;
 }
diff --git a/tests/unit/java/com/android/server/connectivity/ClatCoordinatorTest.java b/tests/unit/java/com/android/server/connectivity/ClatCoordinatorTest.java
index 63050a3..8a2cfc2 100644
--- a/tests/unit/java/com/android/server/connectivity/ClatCoordinatorTest.java
+++ b/tests/unit/java/com/android/server/connectivity/ClatCoordinatorTest.java
@@ -26,13 +26,10 @@
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.fail;
-import static org.mockito.Mockito.anyInt;
-import static org.mockito.Mockito.anyString;
 import static org.mockito.Mockito.argThat;
 import static org.mockito.Mockito.clearInvocations;
 import static org.mockito.Mockito.eq;
 import static org.mockito.Mockito.inOrder;
-import static org.mockito.Mockito.never;
 
 import android.annotation.NonNull;
 import android.net.INetd;
@@ -278,6 +275,16 @@
             fail("unsupported arg: " + sock);
             return 0;
         }
+
+        /**
+         * Untag socket.
+         */
+        @Override
+        public void untagSocket(long cookie) throws IOException {
+            if (cookie != RAW_SOCK_COOKIE) {
+                fail("unsupported arg: " + cookie);
+            }
+        }
     };
 
     @NonNull
@@ -364,13 +371,12 @@
         coordinator.clatStop();
         inOrder.verify(mDeps).stopClatd(eq(BASE_IFACE), eq(NAT64_PREFIX_STRING),
                 eq(XLAT_LOCAL_IPV4ADDR_STRING), eq(XLAT_LOCAL_IPV6ADDR_STRING), eq(CLATD_PID));
+        inOrder.verify(mDeps).untagSocket(eq(RAW_SOCK_COOKIE));
         inOrder.verifyNoMoreInteractions();
 
         // [4] Expect an IO exception while stopping a clatd that doesn't exist.
         assertThrows("java.io.IOException: Clatd has not started", IOException.class,
                 () -> coordinator.clatStop());
-        inOrder.verify(mDeps, never()).stopClatd(anyString(), anyString(), anyString(),
-                anyString(), anyInt());
         inOrder.verifyNoMoreInteractions();
     }