Add bpf map based getUidNetworkingBlockedReasons

Bug: 328732146
Test: NetworkStackBpfNetMapsTest BpfNetMapsTest
Change-Id: Ie802b3d18463e2b7e8a2b953088cbbcc117a841e
diff --git a/framework/src/android/net/BpfNetMapsUtils.java b/framework/src/android/net/BpfNetMapsUtils.java
index 4e01fee..4099e2a 100644
--- a/framework/src/android/net/BpfNetMapsUtils.java
+++ b/framework/src/android/net/BpfNetMapsUtils.java
@@ -37,6 +37,18 @@
 import static android.net.BpfNetMapsConstants.RESTRICTED_MATCH;
 import static android.net.BpfNetMapsConstants.STANDBY_MATCH;
 import static android.net.BpfNetMapsConstants.UID_RULES_CONFIGURATION_KEY;
+import static android.net.ConnectivityManager.BLOCKED_METERED_REASON_ADMIN_DISABLED;
+import static android.net.ConnectivityManager.BLOCKED_METERED_REASON_DATA_SAVER;
+import static android.net.ConnectivityManager.BLOCKED_METERED_REASON_MASK;
+import static android.net.ConnectivityManager.BLOCKED_METERED_REASON_USER_RESTRICTED;
+import static android.net.ConnectivityManager.BLOCKED_REASON_APP_BACKGROUND;
+import static android.net.ConnectivityManager.BLOCKED_REASON_APP_STANDBY;
+import static android.net.ConnectivityManager.BLOCKED_REASON_BATTERY_SAVER;
+import static android.net.ConnectivityManager.BLOCKED_REASON_DOZE;
+import static android.net.ConnectivityManager.BLOCKED_REASON_LOW_POWER_STANDBY;
+import static android.net.ConnectivityManager.BLOCKED_REASON_NONE;
+import static android.net.ConnectivityManager.BLOCKED_REASON_OEM_DENY;
+import static android.net.ConnectivityManager.BLOCKED_REASON_RESTRICTED_MODE;
 import static android.net.ConnectivityManager.FIREWALL_CHAIN_BACKGROUND;
 import static android.net.ConnectivityManager.FIREWALL_CHAIN_DOZABLE;
 import static android.net.ConnectivityManager.FIREWALL_CHAIN_LOW_POWER_STANDBY;
@@ -238,6 +250,67 @@
     }
 
     /**
+     * Get blocked reasons for specified uid
+     *
+     * @param uid Target Uid
+     * @return Reasons of network access blocking for an UID
+     */
+    public static int getUidNetworkingBlockedReasons(final int uid,
+            IBpfMap<S32, U32> configurationMap,
+            IBpfMap<S32, UidOwnerValue> uidOwnerMap,
+            IBpfMap<S32, U8> dataSaverEnabledMap
+    ) {
+        final long uidRuleConfig;
+        final long uidMatch;
+        try {
+            uidRuleConfig = configurationMap.getValue(UID_RULES_CONFIGURATION_KEY).val;
+            final UidOwnerValue value = uidOwnerMap.getValue(new Struct.S32(uid));
+            uidMatch = (value != null) ? value.rule : 0L;
+        } catch (ErrnoException e) {
+            throw new ServiceSpecificException(e.errno,
+                    "Unable to get firewall chain status: " + Os.strerror(e.errno));
+        }
+        final long blockingMatches = (uidRuleConfig & ~uidMatch & sMaskDropIfUnset)
+                | (uidRuleConfig & uidMatch & sMaskDropIfSet);
+
+        int blockedReasons = BLOCKED_REASON_NONE;
+        if ((blockingMatches & POWERSAVE_MATCH) != 0) {
+            blockedReasons |= BLOCKED_REASON_BATTERY_SAVER;
+        }
+        if ((blockingMatches & DOZABLE_MATCH) != 0) {
+            blockedReasons |= BLOCKED_REASON_DOZE;
+        }
+        if ((blockingMatches & STANDBY_MATCH) != 0) {
+            blockedReasons |= BLOCKED_REASON_APP_STANDBY;
+        }
+        if ((blockingMatches & RESTRICTED_MATCH) != 0) {
+            blockedReasons |= BLOCKED_REASON_RESTRICTED_MODE;
+        }
+        if ((blockingMatches & LOW_POWER_STANDBY_MATCH) != 0) {
+            blockedReasons |= BLOCKED_REASON_LOW_POWER_STANDBY;
+        }
+        if ((blockingMatches & BACKGROUND_MATCH) != 0) {
+            blockedReasons |= BLOCKED_REASON_APP_BACKGROUND;
+        }
+        if ((blockingMatches & (OEM_DENY_1_MATCH | OEM_DENY_2_MATCH | OEM_DENY_3_MATCH)) != 0) {
+            blockedReasons |= BLOCKED_REASON_OEM_DENY;
+        }
+
+        // Metered chains are not enabled by configuration map currently.
+        if ((uidMatch & PENALTY_BOX_USER_MATCH) != 0) {
+            blockedReasons |= BLOCKED_METERED_REASON_USER_RESTRICTED;
+        }
+        if ((uidMatch & PENALTY_BOX_ADMIN_MATCH) != 0) {
+            blockedReasons |= BLOCKED_METERED_REASON_ADMIN_DISABLED;
+        }
+        if ((uidMatch & HAPPY_BOX_MATCH) == 0 && getDataSaverEnabled(dataSaverEnabledMap)) {
+            blockedReasons |= BLOCKED_METERED_REASON_DATA_SAVER;
+        }
+
+        return blockedReasons;
+    }
+
+    /**
      * Return whether the network is blocked by firewall chains for the given uid.
      *
      * Note that {@link #getDataSaverEnabled(IBpfMap)} has a latency before V.
@@ -263,27 +336,16 @@
             return false;
         }
 
-        final long uidRuleConfig;
-        final long uidMatch;
-        try {
-            uidRuleConfig = configurationMap.getValue(UID_RULES_CONFIGURATION_KEY).val;
-            final UidOwnerValue value = uidOwnerMap.getValue(new Struct.S32(uid));
-            uidMatch = (value != null) ? value.rule : 0L;
-        } catch (ErrnoException e) {
-            throw new ServiceSpecificException(e.errno,
-                    "Unable to get firewall chain status: " + Os.strerror(e.errno));
+        final int blockedReasons = getUidNetworkingBlockedReasons(
+                uid,
+                configurationMap,
+                uidOwnerMap,
+                dataSaverEnabledMap);
+        if (isNetworkMetered) {
+            return blockedReasons != BLOCKED_REASON_NONE;
+        } else {
+            return (blockedReasons & ~BLOCKED_METERED_REASON_MASK) != BLOCKED_REASON_NONE;
         }
-
-        final boolean blockedByAllowChains = 0 != (uidRuleConfig & ~uidMatch & sMaskDropIfUnset);
-        final boolean blockedByDenyChains = 0 != (uidRuleConfig & uidMatch & sMaskDropIfSet);
-        if (blockedByAllowChains || blockedByDenyChains) {
-            return true;
-        }
-
-        if (!isNetworkMetered) return false;
-        if ((uidMatch & (PENALTY_BOX_USER_MATCH | PENALTY_BOX_ADMIN_MATCH)) != 0) return true;
-        if ((uidMatch & HAPPY_BOX_MATCH) != 0) return false;
-        return getDataSaverEnabled(dataSaverEnabledMap);
     }
 
     /**
diff --git a/service/src/com/android/server/BpfNetMaps.java b/service/src/com/android/server/BpfNetMaps.java
index 04d8ea4..b8a51f6 100644
--- a/service/src/com/android/server/BpfNetMaps.java
+++ b/service/src/com/android/server/BpfNetMaps.java
@@ -863,6 +863,18 @@
         }
     }
 
+    /**
+     * Get blocked reasons for specified uid
+     *
+     * @param uid Target Uid
+     * @return Reasons of network access blocking for an UID
+     */
+    @RequiresApi(Build.VERSION_CODES.TIRAMISU)
+    public int getUidNetworkingBlockedReasons(final int uid) {
+        return BpfNetMapsUtils.getUidNetworkingBlockedReasons(uid,
+                sConfigurationMap, sUidOwnerMap, sDataSaverEnabledMap);
+    }
+
     /** Register callback for statsd to pull atom. */
     @RequiresApi(Build.VERSION_CODES.TIRAMISU)
     public void setPullAtomCallback(final Context context) {
diff --git a/tests/unit/java/com/android/server/BpfNetMapsTest.java b/tests/unit/java/com/android/server/BpfNetMapsTest.java
index fa79795..3fda5c4 100644
--- a/tests/unit/java/com/android/server/BpfNetMapsTest.java
+++ b/tests/unit/java/com/android/server/BpfNetMapsTest.java
@@ -17,6 +17,7 @@
 package com.android.server;
 
 import static android.net.BpfNetMapsConstants.ALLOW_CHAINS;
+import static android.net.BpfNetMapsConstants.BACKGROUND_MATCH;
 import static android.net.BpfNetMapsConstants.CURRENT_STATS_MAP_CONFIGURATION_KEY;
 import static android.net.BpfNetMapsConstants.DATA_SAVER_ENABLED_KEY;
 import static android.net.BpfNetMapsConstants.DATA_SAVER_DISABLED;
@@ -37,6 +38,14 @@
 import static android.net.BpfNetMapsConstants.RESTRICTED_MATCH;
 import static android.net.BpfNetMapsConstants.STANDBY_MATCH;
 import static android.net.BpfNetMapsConstants.UID_RULES_CONFIGURATION_KEY;
+import static android.net.ConnectivityManager.BLOCKED_METERED_REASON_ADMIN_DISABLED;
+import static android.net.ConnectivityManager.BLOCKED_METERED_REASON_DATA_SAVER;
+import static android.net.ConnectivityManager.BLOCKED_METERED_REASON_USER_RESTRICTED;
+import static android.net.ConnectivityManager.BLOCKED_REASON_APP_STANDBY;
+import static android.net.ConnectivityManager.BLOCKED_REASON_BATTERY_SAVER;
+import static android.net.ConnectivityManager.BLOCKED_REASON_DOZE;
+import static android.net.ConnectivityManager.BLOCKED_REASON_NONE;
+import static android.net.ConnectivityManager.BLOCKED_REASON_OEM_DENY;
 import static android.net.ConnectivityManager.FIREWALL_CHAIN_DOZABLE;
 import static android.net.ConnectivityManager.FIREWALL_CHAIN_LOW_POWER_STANDBY;
 import static android.net.ConnectivityManager.FIREWALL_CHAIN_METERED_ALLOW;
@@ -1150,4 +1159,78 @@
         assertDumpContains(dump, TEST_V6_ADDRESS.getHostAddress());
         assertDumpContains(dump, TEST_IF_INDEX + "(" + TEST_IF_NAME + ")");
     }
+
+    private void doTestGetUidNetworkingBlockedReasons(
+            final long configurationMatches,
+            final long uidRules,
+            final short dataSaverStatus,
+            final int expectedBlockedReasons
+    ) throws Exception {
+        mConfigurationMap.updateEntry(UID_RULES_CONFIGURATION_KEY, new U32(configurationMatches));
+        mUidOwnerMap.updateEntry(new S32(TEST_UID), new UidOwnerValue(NULL_IIF, uidRules));
+        mDataSaverEnabledMap.updateEntry(DATA_SAVER_ENABLED_KEY, new U8(dataSaverStatus));
+
+        assertEquals(expectedBlockedReasons, mBpfNetMaps.getUidNetworkingBlockedReasons(TEST_UID));
+    }
+
+    @Test
+    @IgnoreUpTo(Build.VERSION_CODES.S_V2)
+    public void testGetUidNetworkingBlockedReasons() throws Exception {
+        doTestGetUidNetworkingBlockedReasons(
+                NO_MATCH,
+                NO_MATCH,
+                DATA_SAVER_DISABLED,
+                BLOCKED_REASON_NONE
+        );
+        doTestGetUidNetworkingBlockedReasons(
+                DOZABLE_MATCH,
+                NO_MATCH,
+                DATA_SAVER_DISABLED,
+                BLOCKED_REASON_DOZE
+        );
+        doTestGetUidNetworkingBlockedReasons(
+                DOZABLE_MATCH | POWERSAVE_MATCH | STANDBY_MATCH,
+                DOZABLE_MATCH | STANDBY_MATCH,
+                DATA_SAVER_DISABLED,
+                BLOCKED_REASON_BATTERY_SAVER | BLOCKED_REASON_APP_STANDBY
+        );
+        doTestGetUidNetworkingBlockedReasons(
+                OEM_DENY_1_MATCH | OEM_DENY_2_MATCH | OEM_DENY_3_MATCH,
+                OEM_DENY_1_MATCH | OEM_DENY_3_MATCH,
+                DATA_SAVER_DISABLED,
+                BLOCKED_REASON_OEM_DENY
+        );
+        doTestGetUidNetworkingBlockedReasons(
+                DOZABLE_MATCH,
+                DOZABLE_MATCH | BACKGROUND_MATCH | STANDBY_MATCH,
+                DATA_SAVER_DISABLED,
+                BLOCKED_REASON_NONE
+        );
+
+        // Note that HAPPY_BOX and PENALTY_BOX are not disabled by configuration map
+        doTestGetUidNetworkingBlockedReasons(
+                NO_MATCH,
+                PENALTY_BOX_USER_MATCH,
+                DATA_SAVER_DISABLED,
+                BLOCKED_METERED_REASON_USER_RESTRICTED
+        );
+        doTestGetUidNetworkingBlockedReasons(
+                NO_MATCH,
+                PENALTY_BOX_ADMIN_MATCH,
+                DATA_SAVER_ENABLED,
+                BLOCKED_METERED_REASON_ADMIN_DISABLED | BLOCKED_METERED_REASON_DATA_SAVER
+        );
+        doTestGetUidNetworkingBlockedReasons(
+                NO_MATCH,
+                PENALTY_BOX_USER_MATCH | PENALTY_BOX_ADMIN_MATCH | HAPPY_BOX_MATCH,
+                DATA_SAVER_ENABLED,
+                BLOCKED_METERED_REASON_USER_RESTRICTED | BLOCKED_METERED_REASON_ADMIN_DISABLED
+        );
+        doTestGetUidNetworkingBlockedReasons(
+                STANDBY_MATCH,
+                STANDBY_MATCH | PENALTY_BOX_USER_MATCH | HAPPY_BOX_MATCH,
+                DATA_SAVER_ENABLED,
+                BLOCKED_REASON_APP_STANDBY | BLOCKED_METERED_REASON_USER_RESTRICTED
+        );
+    }
 }