From e3e34bdf3a7ab31d36aad9b3010f9d8de1ec53a0 Mon Sep 17 00:00:00 2001
From: Motomu Utsumi <motomuman@google.com>
Date: Mon, 30 Oct 2023 19:42:52 +0900
Subject: [PATCH] Handle v4-mapped v6 address in Struct parsing

testV4MappedV6Address fails without change in Struct.java

Bug: 295800201
Test: atest ConnectivityCoverageTests
Change-Id: I4a40bc47b051860c6420f211491e2ecd34c1d732
---
 .../device/com/android/net/module/util/Struct.java       | 9 ++++++++-
 .../unit/src/com/android/net/module/util/StructTest.java | 8 ++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/staticlibs/device/com/android/net/module/util/Struct.java b/staticlibs/device/com/android/net/module/util/Struct.java
index dc0d19b206..ff7a711899 100644
--- a/staticlibs/device/com/android/net/module/util/Struct.java
+++ b/staticlibs/device/com/android/net/module/util/Struct.java
@@ -422,7 +422,14 @@ public class Struct {
                 final byte[] address = new byte[isIpv6 ? 16 : 4];
                 buf.get(address);
                 try {
-                    value = InetAddress.getByAddress(address);
+                    if (isIpv6) {
+                        // Using Inet6Address.getByAddress since InetAddress.getByAddress converts
+                        // v4-mapped v6 address to v4 address internally and returns Inet4Address.
+                        value = Inet6Address.getByAddress(
+                                null /* host */, address, -1 /* scope_id */);
+                    } else {
+                        value = InetAddress.getByAddress(address);
+                    }
                 } catch (UnknownHostException e) {
                     throw new IllegalArgumentException("illegal length of IP address", e);
                 }
diff --git a/staticlibs/tests/unit/src/com/android/net/module/util/StructTest.java b/staticlibs/tests/unit/src/com/android/net/module/util/StructTest.java
index b4da043953..a39b7a3263 100644
--- a/staticlibs/tests/unit/src/com/android/net/module/util/StructTest.java
+++ b/staticlibs/tests/unit/src/com/android/net/module/util/StructTest.java
@@ -765,6 +765,14 @@ public class StructTest {
                 msg.writeToBytes(ByteOrder.BIG_ENDIAN));
     }
 
+    @Test
+    public void testV4MappedV6Address() {
+        final IpAddressMessage msg = doParsingMessageTest("c0a86401"
+                + "00000000000000000000ffffc0a86401", IpAddressMessage.class, ByteOrder.BIG_ENDIAN);
+        assertEquals(TEST_IPV4_ADDRESS, msg.ipv4Address);
+        assertEquals(InetAddressUtils.v4MappedV6Address(TEST_IPV4_ADDRESS), msg.ipv6Address);
+    }
+
     public static class WrongIpAddressType extends Struct {
         @Field(order = 0, type = Type.Ipv4Address) public byte[] ipv4Address;
         @Field(order = 1, type = Type.Ipv6Address) public byte[] ipv6Address;