[Thread] add an integration test case for NAT64

This CL adds an integration test case for NAT64. Because the feature is
not fully ready, we need some extra setup steps to make the feature
work. That is, specifying a CIDR for NAT64. Also, this test case is
based on `ot-ctl` but eventually the test should be based on API.

This CL requires https://github.com/openthread/openthread/pull/10566.

Bug: 356770473
Test: atest ThreadNetworkIntegrationTests

Change-Id: Idfb5ad848f7b2369591e47558ea67017c0b31e19
diff --git a/thread/tests/integration/src/android/net/thread/BorderRoutingTest.java b/thread/tests/integration/src/android/net/thread/BorderRoutingTest.java
index 48f966f..9e8dc3a 100644
--- a/thread/tests/integration/src/android/net/thread/BorderRoutingTest.java
+++ b/thread/tests/integration/src/android/net/thread/BorderRoutingTest.java
@@ -619,17 +619,36 @@
                         ICMPV6_ECHO_REQUEST_TYPE, ftdOmr, GROUP_ADDR_SCOPE_4));
     }
 
+    @Test
+    public void nat64_threadDevicePingIpv4InfraDevice_outboundPacketIsForwarded() throws Exception {
+        FullThreadDevice ftd = mFtds.get(0);
+        joinNetworkAndWaitForOmr(ftd, DEFAULT_DATASET);
+        // TODO: enable NAT64 via ThreadNetworkController API instead of ot-ctl
+        mOtCtl.setNat64Cidr(NAT64_CIDR);
+        mOtCtl.setNat64Enabled(true);
+        waitFor(() -> mOtCtl.hasNat64PrefixInNetdata(), Duration.ofSeconds(10));
+
+        ftd.ping(IPV4_SERVER_ADDR);
+
+        assertNotNull(pollForIcmpPacketOnInfraNetwork(ICMP_ECHO, null, IPV4_SERVER_ADDR));
     }
 
     private void setUpInfraNetwork() throws Exception {
+        LinkProperties lp = new LinkProperties();
+        // NAT64 feature requires the infra network to have an IPv4 default route.
+        lp.addRoute(
+                new RouteInfo(
+                        new IpPrefix("0.0.0.0/0") /* destination */,
+                        null /* gateway */,
+                        null,
+                        RouteInfo.RTN_UNICAST,
+                        1500 /* mtu */));
         mInfraNetworkTracker =
                 runAsShell(
                         MANAGE_TEST_NETWORKS,
-                        () ->
-                                initTestNetwork(
-                                        mContext, new LinkProperties(), 5000 /* timeoutMs */));
-        mController.setTestNetworkAsUpstreamAndWait(
-                mInfraNetworkTracker.getTestIface().getInterfaceName());
+                        () -> initTestNetwork(mContext, lp, 5000 /* timeoutMs */));
+        String infraNetworkName = mInfraNetworkTracker.getTestIface().getInterfaceName();
+        mController.setTestNetworkAsUpstreamAndWait(infraNetworkName);
     }
 
     private void tearDownInfraNetwork() {
diff --git a/thread/tests/integration/src/android/net/thread/utils/OtDaemonController.java b/thread/tests/integration/src/android/net/thread/utils/OtDaemonController.java
index b3175fd..15a3f5c 100644
--- a/thread/tests/integration/src/android/net/thread/utils/OtDaemonController.java
+++ b/thread/tests/integration/src/android/net/thread/utils/OtDaemonController.java
@@ -105,6 +105,29 @@
         return prefixes.isEmpty() ? null : prefixes.get(0);
     }
 
+    /** Enables/Disables NAT64 feature. */
+    public void setNat64Enabled(boolean enabled) {
+        executeCommand("nat64 " + (enabled ? "enable" : "disable"));
+    }
+
+    /** Sets the NAT64 CIDR. */
+    public void setNat64Cidr(String cidr) {
+        executeCommand("nat64 cidr " + cidr);
+    }
+
+    /** Returns whether there's a NAT64 prefix in network data */
+    public boolean hasNat64PrefixInNetdata() {
+        // Example (in the 'Routes' section):
+        // fdb2:bae3:5b59:2:0:0::/96 sn low c000
+        List<String> outputLines = executeCommandAndParse("netdata show");
+        for (String line : outputLines) {
+            if (line.contains(" sn")) {
+                return true;
+            }
+        }
+        return false;
+    }
+
     public String executeCommand(String cmd) {
         return SystemUtil.runShellCommand(OT_CTL + " " + cmd);
     }