Merge "Introduce property types" (a0ffad60) · Commits · e / os / android_system_core

init/Android.bp

+2 −0

Original line number	Diff line number	Diff line
		@@ -75,6 +75,7 @@ cc_library_static {
		"persistent_properties.cpp",
		"persistent_properties.proto",
		"property_service.cpp",
		"property_type.cpp",
		"security.cpp",
		"selinux.cpp",
		"service.cpp",
		@@ -178,6 +179,7 @@ cc_test {
		"init_test.cpp",
		"persistent_properties_test.cpp",
		"property_service_test.cpp",
		"property_type_test.cpp",
		"result_test.cpp",
		"rlimit_parser_test.cpp",
		"service_test.cpp",

init/property_service.cpp

+57 −59

Original line number	Diff line number	Diff line
		@@ -58,6 +58,7 @@

		#include "init.h"
		#include "persistent_properties.h"
		#include "property_type.h"
		#include "util.h"

		using android::base::ReadFileToString;
		@@ -95,14 +96,9 @@ void property_init() {
		LOG(FATAL) << "Failed to load serialized property info file";
		}
		}
		static bool check_mac_perms(const std::string& name, char* sctx, struct ucred* cr) {
		if (!sctx) {
		return false;
		}

		const char* target_context = nullptr;
		property_info_area->GetPropertyInfo(name.c_str(), &target_context, nullptr);
		if (target_context == nullptr) {
		static bool CheckMacPerms(const std::string& name, const char* target_context,
		const char* source_context, struct ucred* cr) {
		if (!target_context \|\| !source_context) {
		return false;
		}

		@@ -111,29 +107,12 @@ static bool check_mac_perms(const std::string& name, char* sctx, struct ucred* c
		audit_data.name = name.c_str();
		audit_data.cr = cr;

		bool has_access =
		(selinux_check_access(sctx, target_context, "property_service", "set", &audit_data) == 0);
		bool has_access = (selinux_check_access(source_context, target_context, "property_service",
		"set", &audit_data) == 0);

		return has_access;
		}

		static int check_control_mac_perms(const char name, char sctx, struct ucred *cr)
		{
		/*
		* Create a name prefix out of ctl.<service name>
		* The new prefix allows the use of the existing
		* property service backend labeling while avoiding
		* mislabels based on true property prefixes.
		*/
		char ctl_name[PROP_VALUE_MAX+4];
		int ret = snprintf(ctl_name, sizeof(ctl_name), "ctl.%s", name);

		if (ret < 0 \|\| (size_t) ret >= sizeof(ctl_name))
		return 0;

		return check_mac_perms(ctl_name, sctx, cr);
		}

		bool is_legal_property_name(const std::string& name) {
		size_t namelen = name.size();

		@@ -422,25 +401,51 @@ static void handle_property_set(SocketConnection& socket,
		struct ucred cr = socket.cred();
		char* source_ctx = nullptr;
		getpeercon(socket.socket(), &source_ctx);
		std::string source_context = source_ctx;
		freecon(source_ctx);

		if (StartsWith(name, "ctl.")) {
		if (check_control_mac_perms(value.c_str(), source_ctx, &cr)) {
		// ctl. properties have their name ctl.<action> and their value is the name of the service to
		// apply that action to. Permissions for these actions are based on the service, so we must
		// create a fake name of ctl.<service> to check permissions.
		auto control_string = "ctl." + value;
		const char* target_context = nullptr;
		const char* type = nullptr;
		property_info_area->GetPropertyInfo(control_string.c_str(), &target_context, &type);
		if (!CheckMacPerms(control_string, target_context, source_context.c_str(), &cr)) {
		LOG(ERROR) << "sys_prop(" << cmd_name << "): Unable to " << (name.c_str() + 4)
		<< " service ctl [" << value << "]"
		<< " uid:" << cr.uid << " gid:" << cr.gid << " pid:" << cr.pid;
		if (!legacy_protocol) {
		socket.SendUint32(PROP_ERROR_HANDLE_CONTROL_MESSAGE);
		}
		return;
		}

		handle_control_message(name.c_str() + 4, value.c_str());
		if (!legacy_protocol) {
		socket.SendUint32(PROP_SUCCESS);
		}
		} else {
		LOG(ERROR) << "sys_prop(" << cmd_name << "): Unable to " << (name.c_str() + 4)
		<< " service ctl [" << value << "]"
		<< " uid:" << cr.uid
		<< " gid:" << cr.gid
		<< " pid:" << cr.pid;
		const char* target_context = nullptr;
		const char* type = nullptr;
		property_info_area->GetPropertyInfo(name.c_str(), &target_context, &type);
		if (!CheckMacPerms(name, target_context, source_context.c_str(), &cr)) {
		LOG(ERROR) << "sys_prop(" << cmd_name << "): permission denied uid:" << cr.uid
		<< " name:" << name;
		if (!legacy_protocol) {
		socket.SendUint32(PROP_ERROR_HANDLE_CONTROL_MESSAGE);
		socket.SendUint32(PROP_ERROR_PERMISSION_DENIED);
		}
		return;
		}
		if (type == nullptr \|\| !CheckType(type, value)) {
		LOG(ERROR) << "sys_prop(" << cmd_name << "): type check failed, type: '"
		<< (type ?: "(null)") << "' value: '" << value << "'";
		if (!legacy_protocol) {
		socket.SendUint32(PROP_ERROR_INVALID_VALUE);
		}
		return;
		}
		} else {
		if (check_mac_perms(name, source_ctx, &cr)) {
		// sys.powerctl is a special property that is used to make the device reboot. We want to log
		// any process that sets this property to be able to accurately blame the cause of a shutdown.
		if (name == "sys.powerctl") {
		@@ -459,17 +464,9 @@ static void handle_property_set(SocketConnection& socket,
		if (!legacy_protocol) {
		socket.SendUint32(result);
		}
		} else {
		LOG(ERROR) << "sys_prop(" << cmd_name << "): permission denied uid:" << cr.uid << " name:" << name;
		if (!legacy_protocol) {
		socket.SendUint32(PROP_ERROR_PERMISSION_DENIED);
		}
		}
		}

		freecon(source_ctx);
		}

		static void handle_property_set_fd() {
		static constexpr uint32_t kDefaultSocketTimeout = 2000; /* ms */

		@@ -764,9 +761,10 @@ void CreateSerializedPropertyInfo() {
		}
		LoadPropertyInfoFromFile("/nonplat_property_contexts", &property_infos);
		}

		auto serialized_contexts = std::string();
		auto error = std::string();
		if (!BuildTrie(property_infos, "u:object_r:default_prop:s0", "\\s*", &serialized_contexts,
		if (!BuildTrie(property_infos, "u:object_r:default_prop:s0", "string", &serialized_contexts,
		&error)) {
		LOG(ERROR) << "Unable to serialize property contexts: " << error;
		return;

init/property_type.cpp

0 → 100644

+81 −0

Original line number	Diff line number	Diff line
		//
		// Copyright (C) 2017 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 "property_type.h"

		#include <android-base/parsedouble.h>
		#include <android-base/parseint.h>
		#include <android-base/strings.h>

		using android::base::ParseDouble;
		using android::base::ParseInt;
		using android::base::ParseUint;
		using android::base::Split;

		namespace android {
		namespace init {

		bool CheckType(const std::string& type_string, const std::string& value) {
		auto type_strings = Split(type_string, " ");
		if (type_strings.empty()) {
		return false;
		}
		auto type = type_strings[0];

		if (type == "string") {
		return true;
		}
		if (type == "bool") {
		return value == "true" \|\| value == "false" \|\| value == "1" \|\| value == "0";
		}
		if (type == "int") {
		int64_t parsed;
		return ParseInt(value, &parsed);
		}
		if (type == "uint") {
		uint64_t parsed;
		if (value.empty() \|\| value.front() == '-') {
		return false;
		}
		return ParseUint(value, &parsed);
		}
		if (type == "double") {
		double parsed;
		return ParseDouble(value.c_str(), &parsed);
		}
		if (type == "size") {
		auto it = value.begin();
		while (it != value.end() && isdigit(*it)) {
		it++;
		}
		if (it == value.begin() \|\| it == value.end() \|\| (it != 'g' && it != 'k' && *it != 'm')) {
		return false;
		}
		it++;
		return it == value.end();
		}
		if (type == "enum") {
		for (auto it = std::next(type_strings.begin()); it != type_strings.end(); ++it) {
		if (*it == value) {
		return true;
		}
		}
		}
		return false;
		}

		} // namespace init
		} // namespace android

init/property_type.h

0 → 100644

+30 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2017 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 _INIT_PROPERTY_TYPE_H
		#define _INIT_PROPERTY_TYPE_H

		#include <string>

		namespace android {
		namespace init {

		bool CheckType(const std::string& type_string, const std::string& value);

		} // namespace init
		} // namespace android

		#endif

init/property_type_test.cpp

0 → 100644

+95 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2017 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 "property_type.h"

		#include <gtest/gtest.h>

		namespace android {
		namespace init {

		TEST(property_type, CheckType_string) {
		EXPECT_TRUE(CheckType("string", ""));
		EXPECT_TRUE(CheckType("string", "-234"));
		EXPECT_TRUE(CheckType("string", "234"));
		EXPECT_TRUE(CheckType("string", "true"));
		EXPECT_TRUE(CheckType("string", "false"));
		EXPECT_TRUE(CheckType("string", "45645634563456345634563456"));
		EXPECT_TRUE(CheckType("string", "some other string"));
		}

		TEST(property_type, CheckType_int) {
		EXPECT_FALSE(CheckType("int", ""));
		EXPECT_FALSE(CheckType("int", "abc"));
		EXPECT_FALSE(CheckType("int", "-abc"));
		EXPECT_TRUE(CheckType("int", "0"));
		EXPECT_TRUE(CheckType("int", std::to_string(std::numeric_limits<int64_t>::min())));
		EXPECT_TRUE(CheckType("int", std::to_string(std::numeric_limits<int64_t>::max())));
		EXPECT_TRUE(CheckType("int", "123"));
		EXPECT_TRUE(CheckType("int", "-123"));
		}

		TEST(property_type, CheckType_uint) {
		EXPECT_FALSE(CheckType("uint", ""));
		EXPECT_FALSE(CheckType("uint", "abc"));
		EXPECT_FALSE(CheckType("uint", "-abc"));
		EXPECT_TRUE(CheckType("uint", "0"));
		EXPECT_TRUE(CheckType("uint", std::to_string(std::numeric_limits<uint64_t>::max())));
		EXPECT_TRUE(CheckType("uint", "123"));
		EXPECT_FALSE(CheckType("uint", "-123"));
		}

		TEST(property_type, CheckType_double) {
		EXPECT_FALSE(CheckType("double", ""));
		EXPECT_FALSE(CheckType("double", "abc"));
		EXPECT_FALSE(CheckType("double", "-abc"));
		EXPECT_TRUE(CheckType("double", "0.0"));
		EXPECT_TRUE(CheckType("double", std::to_string(std::numeric_limits<double>::min())));
		EXPECT_TRUE(CheckType("double", std::to_string(std::numeric_limits<double>::max())));
		EXPECT_TRUE(CheckType("double", "123.1"));
		EXPECT_TRUE(CheckType("double", "-123.1"));
		}

		TEST(property_type, CheckType_size) {
		EXPECT_FALSE(CheckType("size", ""));
		EXPECT_FALSE(CheckType("size", "ab"));
		EXPECT_FALSE(CheckType("size", "abcd"));
		EXPECT_FALSE(CheckType("size", "0"));

		EXPECT_TRUE(CheckType("size", "512g"));
		EXPECT_TRUE(CheckType("size", "512k"));
		EXPECT_TRUE(CheckType("size", "512m"));

		EXPECT_FALSE(CheckType("size", "512gggg"));
		EXPECT_FALSE(CheckType("size", "512mgk"));
		EXPECT_FALSE(CheckType("size", "g"));
		EXPECT_FALSE(CheckType("size", "m"));
		}

		TEST(property_type, CheckType_enum) {
		EXPECT_FALSE(CheckType("enum abc", ""));
		EXPECT_FALSE(CheckType("enum abc", "ab"));
		EXPECT_FALSE(CheckType("enum abc", "abcd"));
		EXPECT_FALSE(CheckType("enum 123 456 789", "0"));

		EXPECT_TRUE(CheckType("enum abc", "abc"));
		EXPECT_TRUE(CheckType("enum 123 456 789", "123"));
		EXPECT_TRUE(CheckType("enum 123 456 789", "456"));
		EXPECT_TRUE(CheckType("enum 123 456 789", "789"));
		}

		} // namespace init
		} // namespace android