From 264cac59bb8bc08c62e124e2b8a0e445f909e648 Mon Sep 17 00:00:00 2001
From: Hungming Chen <nuccachen@google.com>
Date: Thu, 23 Jun 2022 21:26:55 +0800
Subject: [PATCH] Use BpfDump.toBase64EncodedString to dump raw map

Move base64 related bpf map function and constant to f/l/n.
This is preparation for testing BPF map in ClatCoordinator.

Test: atest EthernetTetheringTest
Change-Id: Ieb1e0a0f128c9aa0d7c9f043e90eecf3c61252f5
---
 .../tethering/BpfCoordinator.java             | 31 +++++++------------
 .../android/net/EthernetTetheringTest.java    |  2 +-
 2 files changed, 12 insertions(+), 21 deletions(-)

diff --git a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
index c403548e3d..47de640563 100644
--- a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
+++ b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
@@ -51,7 +51,6 @@ import android.system.ErrnoException;
 import android.system.OsConstants;
 import android.text.TextUtils;
 import android.util.ArraySet;
-import android.util.Base64;
 import android.util.Log;
 import android.util.SparseArray;
 
@@ -61,6 +60,7 @@ import androidx.annotation.Nullable;
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.util.IndentingPrintWriter;
 import com.android.modules.utils.build.SdkLevel;
+import com.android.net.module.util.BpfDump;
 import com.android.net.module.util.BpfMap;
 import com.android.net.module.util.CollectionUtils;
 import com.android.net.module.util.InterfaceParams;
@@ -125,9 +125,6 @@ public class BpfCoordinator {
     private static final String DUMPSYS_RAWMAP_ARG_STATS = "--stats";
     private static final String DUMPSYS_RAWMAP_ARG_UPSTREAM4 = "--upstream4";
 
-    // Using "," as a separator is safe because base64 characters are [0-9a-zA-Z/=+].
-    private static final String DUMP_BASE64_DELIMITER = ",";
-
     /** The names of all the BPF counters defined in bpf_tethering.h. */
     public static final String[] sBpfCounterNames = getBpfCounterNames();
 
@@ -1078,18 +1075,6 @@ public class BpfCoordinator {
         }
     }
 
-    private <K extends Struct, V extends Struct> String bpfMapEntryToBase64String(
-            final K key, final V value) {
-        final byte[] keyBytes = key.writeToBytes();
-        final String keyBase64Str = Base64.encodeToString(keyBytes, Base64.DEFAULT)
-                .replace("\n", "");
-        final byte[] valueBytes = value.writeToBytes();
-        final String valueBase64Str = Base64.encodeToString(valueBytes, Base64.DEFAULT)
-                .replace("\n", "");
-
-        return keyBase64Str + DUMP_BASE64_DELIMITER + valueBase64Str;
-    }
-
     private <K extends Struct, V extends Struct> void dumpRawMap(BpfMap<K, V> map,
             IndentingPrintWriter pw) throws ErrnoException {
         if (map == null) {
@@ -1100,14 +1085,20 @@ public class BpfCoordinator {
             pw.println("No entries");
             return;
         }
-        map.forEach((k, v) -> pw.println(bpfMapEntryToBase64String(k, v)));
+        map.forEach((k, v) -> pw.println(BpfDump.toBase64EncodedString(k, v)));
     }
 
     /**
-     * Dump raw BPF map in base64 encoded strings. For test only.
-     * Only allow to dump one map path once.
-     * Format:
+     * Dump raw BPF map into the base64 encoded strings "<base64 key>,<base64 value>".
+     * Allow to dump only one map path once. For test only.
+     *
+     * Usage:
      * $ dumpsys tethering bpfRawMap --<map name>
+     *
+     * Output:
+     * <base64 encoded key #1>,<base64 encoded value #1>
+     * <base64 encoded key #2>,<base64 encoded value #2>
+     * ..
      */
     public void dumpRawMap(@NonNull IndentingPrintWriter pw, @Nullable String[] args) {
         // TODO: consider checking the arg order that <map name> is after "bpfRawMap". Probably
diff --git a/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
index 819936dddb..c49cf1ed76 100644
--- a/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
+++ b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
@@ -32,6 +32,7 @@ import static android.system.OsConstants.IPPROTO_IP;
 import static android.system.OsConstants.IPPROTO_IPV6;
 import static android.system.OsConstants.IPPROTO_UDP;
 
+import static com.android.net.module.util.BpfDump.BASE64_DELIMITER;
 import static com.android.net.module.util.ConnectivityUtils.isIPv6ULA;
 import static com.android.net.module.util.HexDump.dumpHexString;
 import static com.android.net.module.util.NetworkStackConstants.ETHER_TYPE_IPV4;
@@ -156,7 +157,6 @@ public class EthernetTetheringTest {
     private static final String DUMPSYS_TETHERING_RAWMAP_ARG = "bpfRawMap";
     private static final String DUMPSYS_RAWMAP_ARG_STATS = "--stats";
     private static final String DUMPSYS_RAWMAP_ARG_UPSTREAM4 = "--upstream4";
-    private static final String BASE64_DELIMITER = ",";
     private static final String LINE_DELIMITER = "\\n";
 
     // version=6, traffic class=0x0, flowlabel=0x0;