Encoding of <overlayable> and <policy>

This change defines two new chunks for encoding overlayable information.
RES_TABLE_OVERLAYABLE_POLICY_TYPE contains flags that represent
restrictions enforced on overlays that try to overlay a specific set of
resource ids. The chunk header is followed by ResTable_ref for each id
that belongs to the policy type. A policy chunk will be created for
every unique combination of policies that are defined in overlayable
declarations.

RES_TABLE_OVERLAYABLE_TYPE holds policy blocks. Since <overlayable>
does not currently have any attributes, only one overlayable block is
encoded in an APK.

This change also removes the SPEC_OVERLAYABLE flag because the runtime
does not use the flag, and the overlayable chunk encoding renders it
obsolete.

Bug: 110869880
Bug: 117545186
Test: libandroidfw_tests and aapt2_tests
Change-Id: I45ae9bf4176699f14c85e2b7a2e8560185d8a0b8

9 files changed, 217 insertions, 4 deletions

diff --git a/libs/androidfw/tests/LoadedArsc_test.cpp b/libs/androidfw/tests/LoadedArsc_test.cpp
index ffa48367c252..441356b95d36 100644
--- a/libs/androidfw/tests/LoadedArsc_test.cpp
+++ b/libs/androidfw/tests/LoadedArsc_test.cpp
@@ -22,12 +22,14 @@
 #include "TestHelpers.h"
 #include "data/basic/R.h"
 #include "data/libclient/R.h"
+#include "data/overlayable/R.h"
 #include "data/sparse/R.h"
 #include "data/styles/R.h"
 
 namespace app = com::android::app;
 namespace basic = com::android::basic;
 namespace libclient = com::android::libclient;
+namespace overlayable = com::android::overlayable;
 namespace sparse = com::android::sparse;
 
 using ::android::base::ReadFileToString;
@@ -273,10 +275,44 @@ TEST(LoadedArscTest, LoadOverlay) {
   ASSERT_THAT(LoadedPackage::GetEntry(type_spec->types[0], 0x0000), NotNull());
 }
 
-// structs with size fields (like Res_value, ResTable_entry) should be
-// backwards and forwards compatible (aka checking the size field against
-// sizeof(Res_value) might not be backwards compatible.
-TEST(LoadedArscTest, LoadingShouldBeForwardsAndBackwardsCompatible) { ASSERT_TRUE(false); }
+TEST(LoadedArscTest, LoadOverlayable) {
+  std::string contents;
+  ASSERT_TRUE(ReadFileFromZipToString(GetTestDataPath() + "/overlayable/overlayable.apk",
+                                      "resources.arsc", &contents));
+
+  std::unique_ptr<const LoadedArsc> loaded_arsc =
+      LoadedArsc::Load(StringPiece(contents), nullptr /*loaded_idmap*/, false /*system*/,
+                       false /*load_as_shared_library*/);
+
+  ASSERT_THAT(loaded_arsc, NotNull());
+  const LoadedPackage* package = loaded_arsc->GetPackageById(
+      get_package_id(overlayable::R::string::not_overlayable));
+
+  const OverlayableInfo* info = package->GetOverlayableInfo(
+      overlayable::R::string::not_overlayable);
+  ASSERT_THAT(info, IsNull());
+
+  info = package->GetOverlayableInfo(overlayable::R::string::overlayable1);
+  ASSERT_THAT(info, NotNull());
+  EXPECT_THAT(info->policy_flags, Eq(ResTable_overlayable_policy_header::POLICY_PUBLIC));
+
+  info = package->GetOverlayableInfo(overlayable::R::string::overlayable2);
+  ASSERT_THAT(info, NotNull());
+  EXPECT_THAT(info->policy_flags,
+              Eq(ResTable_overlayable_policy_header::POLICY_SYSTEM_PARTITION
+                 | ResTable_overlayable_policy_header::POLICY_PRODUCT_PARTITION));
+
+  info = package->GetOverlayableInfo(overlayable::R::string::overlayable3);
+  ASSERT_THAT(info, NotNull());
+  EXPECT_THAT(info->policy_flags,
+              Eq(ResTable_overlayable_policy_header::POLICY_VENDOR_PARTITION
+                 | ResTable_overlayable_policy_header::POLICY_PRODUCT_SERVICES_PARTITION
+                 | ResTable_overlayable_policy_header::POLICY_PRODUCT_PARTITION));
+
+  info = package->GetOverlayableInfo(overlayable::R::string::overlayable4);
+  ASSERT_THAT(info, NotNull());
+  EXPECT_THAT(info->policy_flags, Eq(ResTable_overlayable_policy_header::POLICY_PUBLIC));
+}
 
 TEST(LoadedArscTest, ResourceIdentifierIterator) {
   std::string contents;
@@ -326,4 +362,9 @@ TEST(LoadedArscTest, ResourceIdentifierIterator) {
   ASSERT_EQ(end, iter);
 }
 
+// structs with size fields (like Res_value, ResTable_entry) should be
+// backwards and forwards compatible (aka checking the size field against
+// sizeof(Res_value) might not be backwards compatible.
+TEST(LoadedArscTest, LoadingShouldBeForwardsAndBackwardsCompatible) { ASSERT_TRUE(false); }
+
 }  // namespace android
diff --git a/libs/androidfw/tests/data/overlay/overlay.apk b/libs/androidfw/tests/data/overlay/overlay.apk
index 33f961117c44..d37874dcbb40 100644
--- a/libs/androidfw/tests/data/overlay/overlay.apk
+++ b/libs/androidfw/tests/data/overlay/overlay.apk
diff --git a/libs/androidfw/tests/data/overlayable/AndroidManifest.xml b/libs/androidfw/tests/data/overlayable/AndroidManifest.xml
new file mode 100644
index 000000000000..abc2a454e845
--- /dev/null
+++ b/libs/androidfw/tests/data/overlayable/AndroidManifest.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2018 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.android.overlayable">
+    <application>
+    </application>
+</manifest>
diff --git a/libs/androidfw/tests/data/overlayable/R.h b/libs/androidfw/tests/data/overlayable/R.h
new file mode 100644
index 000000000000..e46e264da318
--- /dev/null
+++ b/libs/androidfw/tests/data/overlayable/R.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef TESTS_DATA_OVERLAYABLE_R_H_
+#define TESTS_DATA_OVERLAYABLE_R_H_
+
+#include <cstdint>
+
+namespace com {
+namespace android {
+namespace overlayable {
+
+struct R {
+  struct string {
+    enum : uint32_t {
+      not_overlayable = 0x7f010000,
+      overlayable1 = 0x7f010001,
+      overlayable2 = 0x7f010002,
+      overlayable3 = 0x7f010003,
+      overlayable4 = 0x7f010004,
+    };
+  };
+};
+
+}  // namespace overlayable
+}  // namespace android
+}  // namespace com
+
+#endif /* TESTS_DATA_OVERLAYABLE_R_H_ */
diff --git a/libs/androidfw/tests/data/overlayable/build b/libs/androidfw/tests/data/overlayable/build
new file mode 100755
index 000000000000..98fdc5101160
--- /dev/null
+++ b/libs/androidfw/tests/data/overlayable/build
@@ -0,0 +1,22 @@
+#!/bin/bash
+#
+# Copyright (C) 2018 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+set -e
+
+aapt2 compile --dir res -o compiled.flata
+aapt2 link --manifest AndroidManifest.xml -o overlayable.apk compiled.flata
+rm compiled.flata
diff --git a/libs/androidfw/tests/data/overlayable/overlayable.apk b/libs/androidfw/tests/data/overlayable/overlayable.apk
new file mode 100644
index 000000000000..85ab4be7a2e5
--- /dev/null
+++ b/libs/androidfw/tests/data/overlayable/overlayable.apk
diff --git a/libs/androidfw/tests/data/overlayable/res/values/overlayable.xml b/libs/androidfw/tests/data/overlayable/res/values/overlayable.xml
new file mode 100644
index 000000000000..11aa7354901d
--- /dev/null
+++ b/libs/androidfw/tests/data/overlayable/res/values/overlayable.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2018 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<resources>
+<overlayable>
+    <!-- Any overlay can overlay the value of @string/overlayable1 -->
+    <item type="string" name="overlayable1" />
+
+    <!-- Any overlay on the product or system partition can overlay the value of
+        @string/overlayable2 -->
+    <policy type="product|system">
+        <item type="string" name="overlayable2" />
+    </policy>
+
+    <!-- Any overlay can overlay the value of @string/overlayable4 -->
+    <policy type="public">
+        <item type="string" name="overlayable4" />
+    </policy>
+</overlayable>
+
+<overlayable>
+    <!-- Any overlay on the product_services, vendor, or product partition can overlay the value of
+   @string/overlayable3 -->
+    <policy type="product_services|vendor|product">
+        <item type="string" name="overlayable3" />
+    </policy>
+</overlayable>
+</resources>
\ No newline at end of file
diff --git a/libs/androidfw/tests/data/overlayable/res/values/public.xml b/libs/androidfw/tests/data/overlayable/res/values/public.xml
new file mode 100644
index 000000000000..5676d7cc64c9
--- /dev/null
+++ b/libs/androidfw/tests/data/overlayable/res/values/public.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2018 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<resources>
+    <public type="string" name="not_overlayable" id="0x7f010000" />
+    <public type="string" name="overlayable1" id="0x7f010001" />
+    <public type="string" name="overlayable2" id="0x7f010002" />
+    <public type="string" name="overlayable3" id="0x7f010003" />
+    <public type="string" name="overlayable4" id="0x7f010004" />
+</resources>
\ No newline at end of file
diff --git a/libs/androidfw/tests/data/overlayable/res/values/values.xml b/libs/androidfw/tests/data/overlayable/res/values/values.xml
new file mode 100644
index 000000000000..a86b31282bc9
--- /dev/null
+++ b/libs/androidfw/tests/data/overlayable/res/values/values.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2018 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<resources>
+    <string name="not_overlayable">Not overlayable</string>
+    <string name="overlayable1">Overlayable One</string>
+    <string name="overlayable2">Overlayable Two</string>
+    <string name="overlayable3">Overlayable Three</string>
+    <string name="overlayable4">Overlayable Four</string>
+</resources>