Merge "rpc_binder: Refactor C/Rust bindings to control server lifetime"
diff --git a/libs/binder/IPCThreadState.cpp b/libs/binder/IPCThreadState.cpp
index 11c8e5d..7770374 100644
--- a/libs/binder/IPCThreadState.cpp
+++ b/libs/binder/IPCThreadState.cpp
@@ -45,11 +45,11 @@
 
 #define IF_LOG_TRANSACTIONS() if (false)
 #define IF_LOG_COMMANDS() if (false)
-#define LOG_REMOTEREFS(...) 
+#define LOG_REMOTEREFS(...)
 #define IF_LOG_REMOTEREFS() if (false)
 
-#define LOG_THREADPOOL(...) 
-#define LOG_ONEWAY(...) 
+#define LOG_THREADPOOL(...)
+#define LOG_ONEWAY(...)
 
 #else
 
@@ -394,14 +394,92 @@
     // context, so we don't abort
 }
 
+constexpr uint32_t encodeExplicitIdentity(bool hasExplicitIdentity, pid_t callingPid) {
+    uint32_t as_unsigned = static_cast<uint32_t>(callingPid);
+    if (hasExplicitIdentity) {
+        return as_unsigned | (1 << 30);
+    } else {
+        return as_unsigned & ~(1 << 30);
+    }
+}
+
+constexpr int64_t packCallingIdentity(bool hasExplicitIdentity, uid_t callingUid,
+                                      pid_t callingPid) {
+    // Calling PID is a 32-bit signed integer, but doesn't consume the entire 32 bit space.
+    // To future-proof this and because we have extra capacity, we decided to also support -1,
+    // since this constant is used to represent invalid UID in other places of the system.
+    // Thus, we pack hasExplicitIdentity into the 2nd bit from the left.  This allows us to
+    // preserve the (left-most) bit for the sign while also encoding the value of
+    // hasExplicitIdentity.
+    //               32b     |        1b         |         1b            |        30b
+    // token = [ calling uid | calling pid(sign) | has explicit identity | calling pid(rest) ]
+    uint64_t token = (static_cast<uint64_t>(callingUid) << 32) |
+            encodeExplicitIdentity(hasExplicitIdentity, callingPid);
+    return static_cast<int64_t>(token);
+}
+
+constexpr bool unpackHasExplicitIdentity(int64_t token) {
+    return static_cast<int32_t>(token) & (1 << 30);
+}
+
+constexpr uid_t unpackCallingUid(int64_t token) {
+    return static_cast<uid_t>(token >> 32);
+}
+
+constexpr pid_t unpackCallingPid(int64_t token) {
+    int32_t encodedPid = static_cast<int32_t>(token);
+    if (encodedPid & (1 << 31)) {
+        return encodedPid | (1 << 30);
+    } else {
+        return encodedPid & ~(1 << 30);
+    }
+}
+
+static_assert(unpackHasExplicitIdentity(packCallingIdentity(true, 1000, 9999)) == true,
+              "pack true hasExplicit");
+
+static_assert(unpackCallingUid(packCallingIdentity(true, 1000, 9999)) == 1000, "pack true uid");
+
+static_assert(unpackCallingPid(packCallingIdentity(true, 1000, 9999)) == 9999, "pack true pid");
+
+static_assert(unpackHasExplicitIdentity(packCallingIdentity(false, 1000, 9999)) == false,
+              "pack false hasExplicit");
+
+static_assert(unpackCallingUid(packCallingIdentity(false, 1000, 9999)) == 1000, "pack false uid");
+
+static_assert(unpackCallingPid(packCallingIdentity(false, 1000, 9999)) == 9999, "pack false pid");
+
+static_assert(unpackHasExplicitIdentity(packCallingIdentity(true, 1000, -1)) == true,
+              "pack true (negative) hasExplicit");
+
+static_assert(unpackCallingUid(packCallingIdentity(true, 1000, -1)) == 1000,
+              "pack true (negative) uid");
+
+static_assert(unpackCallingPid(packCallingIdentity(true, 1000, -1)) == -1,
+              "pack true (negative) pid");
+
+static_assert(unpackHasExplicitIdentity(packCallingIdentity(false, 1000, -1)) == false,
+              "pack false (negative) hasExplicit");
+
+static_assert(unpackCallingUid(packCallingIdentity(false, 1000, -1)) == 1000,
+              "pack false (negative) uid");
+
+static_assert(unpackCallingPid(packCallingIdentity(false, 1000, -1)) == -1,
+              "pack false (negative) pid");
+
 int64_t IPCThreadState::clearCallingIdentity()
 {
     // ignore mCallingSid for legacy reasons
-    int64_t token = ((int64_t)mCallingUid<<32) | mCallingPid;
+    int64_t token = packCallingIdentity(mHasExplicitIdentity, mCallingUid, mCallingPid);
     clearCaller();
+    mHasExplicitIdentity = true;
     return token;
 }
 
+bool IPCThreadState::hasExplicitIdentity() {
+    return mHasExplicitIdentity;
+}
+
 void IPCThreadState::setStrictModePolicy(int32_t policy)
 {
     mStrictModePolicy = policy;
@@ -474,9 +552,10 @@
 
 void IPCThreadState::restoreCallingIdentity(int64_t token)
 {
-    mCallingUid = (int)(token>>32);
+    mCallingUid = unpackCallingUid(token);
     mCallingSid = nullptr;  // not enough data to restore
-    mCallingPid = (int)token;
+    mCallingPid = unpackCallingPid(token);
+    mHasExplicitIdentity = unpackHasExplicitIdentity(token);
 }
 
 void IPCThreadState::clearCaller()
@@ -889,6 +968,7 @@
         mCallRestriction(mProcess->mCallRestriction) {
     pthread_setspecific(gTLS, this);
     clearCaller();
+    mHasExplicitIdentity = false;
     mIn.setDataCapacity(256);
     mOut.setDataCapacity(256);
 }
@@ -1279,6 +1359,7 @@
             const pid_t origPid = mCallingPid;
             const char* origSid = mCallingSid;
             const uid_t origUid = mCallingUid;
+            const bool origHasExplicitIdentity = mHasExplicitIdentity;
             const int32_t origStrictModePolicy = mStrictModePolicy;
             const int32_t origTransactionBinderFlags = mLastTransactionBinderFlags;
             const int32_t origWorkSource = mWorkSource;
@@ -1292,6 +1373,7 @@
             mCallingPid = tr.sender_pid;
             mCallingSid = reinterpret_cast<const char*>(tr_secctx.secctx);
             mCallingUid = tr.sender_euid;
+            mHasExplicitIdentity = false;
             mLastTransactionBinderFlags = tr.flags;
 
             // ALOGI(">>>> TRANSACT from pid %d sid %s uid %d\n", mCallingPid,
@@ -1367,6 +1449,7 @@
             mCallingPid = origPid;
             mCallingSid = origSid;
             mCallingUid = origUid;
+            mHasExplicitIdentity = origHasExplicitIdentity;
             mStrictModePolicy = origStrictModePolicy;
             mLastTransactionBinderFlags = origTransactionBinderFlags;
             mWorkSource = origWorkSource;
diff --git a/libs/binder/include/binder/IPCThreadState.h b/libs/binder/include/binder/IPCThreadState.h
index c01e92f..65b77c6 100644
--- a/libs/binder/include/binder/IPCThreadState.h
+++ b/libs/binder/include/binder/IPCThreadState.h
@@ -139,6 +139,7 @@
             int64_t             clearCallingIdentity();
             // Restores PID/UID (not SID)
             void                restoreCallingIdentity(int64_t token);
+            bool hasExplicitIdentity();
 
             status_t            setupPolling(int* fd);
             status_t            handlePolledCommands();
@@ -241,6 +242,7 @@
             bool                mPropagateWorkSource;
             bool                mIsLooper;
             bool mIsFlushing;
+            bool mHasExplicitIdentity;
             int32_t             mStrictModePolicy;
             int32_t             mLastTransactionBinderFlags;
             CallRestriction     mCallRestriction;
diff --git a/libs/fakeservicemanager/ServiceManager.cpp b/libs/fakeservicemanager/ServiceManager.cpp
index 480ec79..1109ad8 100644
--- a/libs/fakeservicemanager/ServiceManager.cpp
+++ b/libs/fakeservicemanager/ServiceManager.cpp
@@ -36,6 +36,9 @@
 status_t ServiceManager::addService(const String16& name, const sp<IBinder>& service,
                                 bool /*allowIsolated*/,
                                 int /*dumpsysFlags*/) {
+    if (service == nullptr) {
+        return UNEXPECTED_NULL;
+    }
     mNameToService[name] = service;
     return NO_ERROR;
 }
@@ -103,4 +106,8 @@
     std::vector<IServiceManager::ServiceDebugInfo> ret;
     return ret;
 }
+
+void ServiceManager::clear() {
+    mNameToService.clear();
+}
 }  // namespace android
diff --git a/libs/fakeservicemanager/include/fakeservicemanager/ServiceManager.h b/libs/fakeservicemanager/include/fakeservicemanager/ServiceManager.h
index ee0637e..ba6bb7d 100644
--- a/libs/fakeservicemanager/include/fakeservicemanager/ServiceManager.h
+++ b/libs/fakeservicemanager/include/fakeservicemanager/ServiceManager.h
@@ -64,6 +64,9 @@
 
     std::vector<IServiceManager::ServiceDebugInfo> getServiceDebugInfo() override;
 
+    // Clear all of the registered services
+    void clear();
+
 private:
     std::map<String16, sp<IBinder>> mNameToService;
 };
diff --git a/libs/fakeservicemanager/test_sm.cpp b/libs/fakeservicemanager/test_sm.cpp
index 71e5abe..8682c1c 100644
--- a/libs/fakeservicemanager/test_sm.cpp
+++ b/libs/fakeservicemanager/test_sm.cpp
@@ -50,6 +50,12 @@
         IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
 }
 
+TEST(AddService, SadNullBinder) {
+    auto sm = new ServiceManager();
+    EXPECT_EQ(sm->addService(String16("foo"), nullptr, false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), android::UNEXPECTED_NULL);
+}
+
 TEST(AddService, HappyOverExistingService) {
     auto sm = new ServiceManager();
     EXPECT_EQ(sm->addService(String16("foo"), getBinder(), false /*allowIsolated*/,
@@ -58,6 +64,15 @@
         IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
 }
 
+TEST(AddService, HappyClearAddedService) {
+    auto sm = new ServiceManager();
+    EXPECT_EQ(sm->addService(String16("foo"), getBinder(), false /*allowIsolated*/,
+        IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT), OK);
+    EXPECT_NE(sm->getService(String16("foo")), nullptr);
+    sm->clear();
+    EXPECT_EQ(sm->getService(String16("foo")), nullptr);
+}
+
 TEST(GetService, HappyHappy) {
     auto sm = new ServiceManager();
     sp<IBinder> service = getBinder();
diff --git a/libs/sensor/Android.bp b/libs/sensor/Android.bp
index 2b93c6e..b6b9cc4 100644
--- a/libs/sensor/Android.bp
+++ b/libs/sensor/Android.bp
@@ -21,9 +21,10 @@
     default_applicable_licenses: ["frameworks_native_license"],
 }
 
-cc_library_shared {
+cc_library {
     name: "libsensor",
 
+    host_supported: true,
     cflags: [
         "-Wall",
         "-Werror",
diff --git a/services/sensorservice/aidl/Android.bp b/services/sensorservice/aidl/Android.bp
index bbf49da..34d1de7 100644
--- a/services/sensorservice/aidl/Android.bp
+++ b/services/sensorservice/aidl/Android.bp
@@ -7,7 +7,7 @@
     default_applicable_licenses: ["frameworks_native_license"],
 }
 
-cc_library_shared {
+cc_library {
     name: "libsensorserviceaidl",
     srcs: [
         "EventQueue.cpp",
@@ -15,6 +15,7 @@
         "SensorManager.cpp",
         "utils.cpp",
     ],
+    host_supported: true,
     cflags: [
         "-Wall",
         "-Werror",
diff --git a/services/sensorservice/aidl/EventQueue.cpp b/services/sensorservice/aidl/EventQueue.cpp
index d4e8906..88ab7a7 100644
--- a/services/sensorservice/aidl/EventQueue.cpp
+++ b/services/sensorservice/aidl/EventQueue.cpp
@@ -34,7 +34,7 @@
                              std::shared_ptr<IEventQueueCallback> callback)
           : mQueue(queue), mCallback(callback) {}
 
-    int handleEvent(__unused int fd, __unused int events, __unused void* data) {
+    int handleEvent(int /* fd */, int /* events */, void* /* data */) {
         ASensorEvent event;
         ssize_t actual;
 
diff --git a/services/sensorservice/aidl/fuzzer/Android.bp b/services/sensorservice/aidl/fuzzer/Android.bp
new file mode 100644
index 0000000..0d6e476
--- /dev/null
+++ b/services/sensorservice/aidl/fuzzer/Android.bp
@@ -0,0 +1,52 @@
+package {
+    // See: http://go/android-license-faq
+    // A large-scale-change added 'default_applicable_licenses' to import
+    // all of the 'license_kinds' from "frameworks_native_license"
+    // to get the below license kinds:
+    //   SPDX-license-identifier-Apache-2.0
+    default_applicable_licenses: ["frameworks_native_license"],
+}
+
+cc_fuzz {
+    name: "libsensorserviceaidl_fuzzer",
+    defaults: [
+        "service_fuzzer_defaults",
+    ],
+    host_supported: true,
+    static_libs: [
+        "libsensorserviceaidl",
+        "libpermission",
+        "android.frameworks.sensorservice-V1-ndk",
+        "android.hardware.sensors-V1-convert",
+        "android.hardware.sensors-V1-ndk",
+        "android.hardware.common-V2-ndk",
+        "libsensor",
+        "libfakeservicemanager",
+        "libcutils",
+        "liblog",
+    ],
+    srcs: [
+        "fuzzer.cpp",
+    ],
+    fuzz_config: {
+        cc: [
+            "android-sensors@google.com",
+            "devinmoore@google.com",
+        ],
+    },
+    sanitize: {
+        misc_undefined: [
+            "signed-integer-overflow",
+            "unsigned-integer-overflow",
+        ],
+        diag: {
+            misc_undefined: [
+                "signed-integer-overflow",
+                "unsigned-integer-overflow",
+            ],
+        },
+        address: true,
+        integer_overflow: true,
+    },
+
+}
diff --git a/services/sensorservice/aidl/fuzzer/fuzzer.cpp b/services/sensorservice/aidl/fuzzer/fuzzer.cpp
new file mode 100644
index 0000000..1b63d76
--- /dev/null
+++ b/services/sensorservice/aidl/fuzzer/fuzzer.cpp
@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+#include <fuzzbinder/libbinder_ndk_driver.h>
+#include <fuzzer/FuzzedDataProvider.h>
+
+#include <ServiceManager.h>
+#include <android-base/logging.h>
+#include <android/binder_interface_utils.h>
+#include <fuzzbinder/random_binder.h>
+#include <sensorserviceaidl/SensorManagerAidl.h>
+
+using android::fuzzService;
+using android::frameworks::sensorservice::implementation::SensorManagerAidl;
+using ndk::SharedRefBase;
+
+[[clang::no_destroy]] static std::once_flag gSmOnce;
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+    static android::sp<android::ServiceManager> fakeServiceManager = new android::ServiceManager();
+    std::call_once(gSmOnce, [&] { setDefaultServiceManager(fakeServiceManager); });
+    fakeServiceManager->clear();
+
+    FuzzedDataProvider fdp(data, size);
+    android::sp<android::IBinder> binder = android::getRandomBinder(&fdp);
+    if (binder == nullptr) {
+        // Nothing to do if we get a null binder. It will cause SensorManager to
+        // hang while trying to get sensorservice.
+        return 0;
+    }
+
+    CHECK(android::NO_ERROR == fakeServiceManager->addService(android::String16("sensorservice"),
+                                   binder));
+
+    std::shared_ptr<SensorManagerAidl> sensorService =
+            ndk::SharedRefBase::make<SensorManagerAidl>(nullptr);
+
+    fuzzService(sensorService->asBinder().get(), std::move(fdp));
+
+    return 0;
+}