| /* |
| * Copyright (C) 2007 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_service.h" |
| |
| #include <android/api-level.h> |
| #include <ctype.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <inttypes.h> |
| #include <limits.h> |
| #include <netinet/in.h> |
| #include <stdarg.h> |
| #include <stddef.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/mman.h> |
| #include <sys/poll.h> |
| #include <sys/select.h> |
| #include <sys/types.h> |
| #include <sys/un.h> |
| #include <unistd.h> |
| #include <wchar.h> |
| |
| #define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_ |
| #include <sys/_system_properties.h> |
| |
| #include <map> |
| #include <memory> |
| #include <mutex> |
| #include <optional> |
| #include <queue> |
| #include <thread> |
| #include <vector> |
| |
| #include <android-base/chrono_utils.h> |
| #include <android-base/file.h> |
| #include <android-base/logging.h> |
| #include <android-base/properties.h> |
| #include <android-base/stringprintf.h> |
| #include <android-base/strings.h> |
| #include <property_info_parser/property_info_parser.h> |
| #include <property_info_serializer/property_info_serializer.h> |
| #include <selinux/android.h> |
| #include <selinux/label.h> |
| #include <selinux/selinux.h> |
| |
| #include "debug_ramdisk.h" |
| #include "epoll.h" |
| #include "init.h" |
| #include "persistent_properties.h" |
| #include "property_type.h" |
| #include "proto_utils.h" |
| #include "selinux.h" |
| #include "subcontext.h" |
| #include "system/core/init/property_service.pb.h" |
| #include "util.h" |
| |
| using namespace std::literals; |
| |
| using android::base::GetProperty; |
| using android::base::ReadFileToString; |
| using android::base::Split; |
| using android::base::StartsWith; |
| using android::base::StringPrintf; |
| using android::base::Timer; |
| using android::base::Trim; |
| using android::base::unique_fd; |
| using android::base::WriteStringToFile; |
| using android::properties::BuildTrie; |
| using android::properties::ParsePropertyInfoFile; |
| using android::properties::PropertyInfoAreaFile; |
| using android::properties::PropertyInfoEntry; |
| |
| namespace android { |
| namespace init { |
| |
| static bool persistent_properties_loaded = false; |
| |
| static int property_set_fd = -1; |
| static int init_socket = -1; |
| |
| static PropertyInfoAreaFile property_info_area; |
| |
| void CreateSerializedPropertyInfo(); |
| |
| struct PropertyAuditData { |
| const ucred* cr; |
| const char* name; |
| }; |
| |
| static int PropertyAuditCallback(void* data, security_class_t /*cls*/, char* buf, size_t len) { |
| auto* d = reinterpret_cast<PropertyAuditData*>(data); |
| |
| if (!d || !d->name || !d->cr) { |
| LOG(ERROR) << "AuditCallback invoked with null data arguments!"; |
| return 0; |
| } |
| |
| snprintf(buf, len, "property=%s pid=%d uid=%d gid=%d", d->name, d->cr->pid, d->cr->uid, |
| d->cr->gid); |
| return 0; |
| } |
| |
| void property_init() { |
| selinux_callback cb; |
| cb.func_audit = PropertyAuditCallback; |
| selinux_set_callback(SELINUX_CB_AUDIT, cb); |
| |
| mkdir("/dev/__properties__", S_IRWXU | S_IXGRP | S_IXOTH); |
| CreateSerializedPropertyInfo(); |
| if (__system_property_area_init()) { |
| LOG(FATAL) << "Failed to initialize property area"; |
| } |
| if (!property_info_area.LoadDefaultPath()) { |
| LOG(FATAL) << "Failed to load serialized property info file"; |
| } |
| } |
| |
| bool CanReadProperty(const std::string& source_context, const std::string& name) { |
| const char* target_context = nullptr; |
| property_info_area->GetPropertyInfo(name.c_str(), &target_context, nullptr); |
| |
| PropertyAuditData audit_data; |
| |
| audit_data.name = name.c_str(); |
| |
| ucred cr = {.pid = 0, .uid = 0, .gid = 0}; |
| audit_data.cr = &cr; |
| |
| return selinux_check_access(source_context.c_str(), target_context, "file", "read", |
| &audit_data) == 0; |
| } |
| |
| static bool CheckMacPerms(const std::string& name, const char* target_context, |
| const char* source_context, const ucred& cr) { |
| if (!target_context || !source_context) { |
| return false; |
| } |
| |
| PropertyAuditData audit_data; |
| |
| audit_data.name = name.c_str(); |
| audit_data.cr = &cr; |
| |
| bool has_access = (selinux_check_access(source_context, target_context, "property_service", |
| "set", &audit_data) == 0); |
| |
| return has_access; |
| } |
| |
| static void SendPropertyChanged(const std::string& name, const std::string& value) { |
| auto property_msg = PropertyMessage{}; |
| auto* changed_message = property_msg.mutable_changed_message(); |
| changed_message->set_name(name); |
| changed_message->set_value(value); |
| |
| if (auto result = SendMessage(init_socket, property_msg); !result) { |
| LOG(ERROR) << "Failed to send property changed message: " << result.error(); |
| } |
| } |
| |
| static uint32_t PropertySet(const std::string& name, const std::string& value, std::string* error) { |
| size_t valuelen = value.size(); |
| |
| if (!IsLegalPropertyName(name)) { |
| *error = "Illegal property name"; |
| return PROP_ERROR_INVALID_NAME; |
| } |
| |
| if (auto result = IsLegalPropertyValue(name, value); !result) { |
| *error = result.error().message(); |
| return PROP_ERROR_INVALID_VALUE; |
| } |
| |
| prop_info* pi = (prop_info*) __system_property_find(name.c_str()); |
| if (pi != nullptr) { |
| // ro.* properties are actually "write-once". |
| if (StartsWith(name, "ro.")) { |
| *error = "Read-only property was already set"; |
| return PROP_ERROR_READ_ONLY_PROPERTY; |
| } |
| |
| __system_property_update(pi, value.c_str(), valuelen); |
| } else { |
| int rc = __system_property_add(name.c_str(), name.size(), value.c_str(), valuelen); |
| if (rc < 0) { |
| *error = "__system_property_add failed"; |
| return PROP_ERROR_SET_FAILED; |
| } |
| } |
| |
| // Don't write properties to disk until after we have read all default |
| // properties to prevent them from being overwritten by default values. |
| if (persistent_properties_loaded && StartsWith(name, "persist.")) { |
| WritePersistentProperty(name, value); |
| } |
| // If init hasn't started its main loop, then it won't be handling property changed messages |
| // anyway, so there's no need to try to send them. |
| if (init_socket != -1) { |
| SendPropertyChanged(name, value); |
| } |
| return PROP_SUCCESS; |
| } |
| |
| class AsyncRestorecon { |
| public: |
| void TriggerRestorecon(const std::string& path) { |
| auto guard = std::lock_guard{mutex_}; |
| paths_.emplace(path); |
| |
| if (!thread_started_) { |
| thread_started_ = true; |
| std::thread{&AsyncRestorecon::ThreadFunction, this}.detach(); |
| } |
| } |
| |
| private: |
| void ThreadFunction() { |
| auto lock = std::unique_lock{mutex_}; |
| |
| while (!paths_.empty()) { |
| auto path = paths_.front(); |
| paths_.pop(); |
| |
| lock.unlock(); |
| if (selinux_android_restorecon(path.c_str(), SELINUX_ANDROID_RESTORECON_RECURSE) != 0) { |
| LOG(ERROR) << "Asynchronous restorecon of '" << path << "' failed'"; |
| } |
| android::base::SetProperty(kRestoreconProperty, path); |
| lock.lock(); |
| } |
| |
| thread_started_ = false; |
| } |
| |
| std::mutex mutex_; |
| std::queue<std::string> paths_; |
| bool thread_started_ = false; |
| }; |
| |
| class SocketConnection { |
| public: |
| SocketConnection(int socket, const ucred& cred) : socket_(socket), cred_(cred) {} |
| |
| bool RecvUint32(uint32_t* value, uint32_t* timeout_ms) { |
| return RecvFully(value, sizeof(*value), timeout_ms); |
| } |
| |
| bool RecvChars(char* chars, size_t size, uint32_t* timeout_ms) { |
| return RecvFully(chars, size, timeout_ms); |
| } |
| |
| bool RecvString(std::string* value, uint32_t* timeout_ms) { |
| uint32_t len = 0; |
| if (!RecvUint32(&len, timeout_ms)) { |
| return false; |
| } |
| |
| if (len == 0) { |
| *value = ""; |
| return true; |
| } |
| |
| // http://b/35166374: don't allow init to make arbitrarily large allocations. |
| if (len > 0xffff) { |
| LOG(ERROR) << "sys_prop: RecvString asked to read huge string: " << len; |
| errno = ENOMEM; |
| return false; |
| } |
| |
| std::vector<char> chars(len); |
| if (!RecvChars(&chars[0], len, timeout_ms)) { |
| return false; |
| } |
| |
| *value = std::string(&chars[0], len); |
| return true; |
| } |
| |
| bool SendUint32(uint32_t value) { |
| if (!socket_.ok()) { |
| return true; |
| } |
| int result = TEMP_FAILURE_RETRY(send(socket_, &value, sizeof(value), 0)); |
| return result == sizeof(value); |
| } |
| |
| bool GetSourceContext(std::string* source_context) const { |
| char* c_source_context = nullptr; |
| if (getpeercon(socket_, &c_source_context) != 0) { |
| return false; |
| } |
| *source_context = c_source_context; |
| freecon(c_source_context); |
| return true; |
| } |
| |
| [[nodiscard]] int Release() { return socket_.release(); } |
| |
| const ucred& cred() { return cred_; } |
| |
| private: |
| bool PollIn(uint32_t* timeout_ms) { |
| struct pollfd ufds[1]; |
| ufds[0].fd = socket_; |
| ufds[0].events = POLLIN; |
| ufds[0].revents = 0; |
| while (*timeout_ms > 0) { |
| auto start_time = std::chrono::steady_clock::now(); |
| int nr = poll(ufds, 1, *timeout_ms); |
| auto now = std::chrono::steady_clock::now(); |
| auto time_elapsed = |
| std::chrono::duration_cast<std::chrono::milliseconds>(now - start_time); |
| uint64_t millis = time_elapsed.count(); |
| *timeout_ms = (millis > *timeout_ms) ? 0 : *timeout_ms - millis; |
| |
| if (nr > 0) { |
| return true; |
| } |
| |
| if (nr == 0) { |
| // Timeout |
| break; |
| } |
| |
| if (nr < 0 && errno != EINTR) { |
| PLOG(ERROR) << "sys_prop: error waiting for uid " << cred_.uid |
| << " to send property message"; |
| return false; |
| } else { // errno == EINTR |
| // Timer rounds milliseconds down in case of EINTR we want it to be rounded up |
| // to avoid slowing init down by causing EINTR with under millisecond timeout. |
| if (*timeout_ms > 0) { |
| --(*timeout_ms); |
| } |
| } |
| } |
| |
| LOG(ERROR) << "sys_prop: timeout waiting for uid " << cred_.uid |
| << " to send property message."; |
| return false; |
| } |
| |
| bool RecvFully(void* data_ptr, size_t size, uint32_t* timeout_ms) { |
| size_t bytes_left = size; |
| char* data = static_cast<char*>(data_ptr); |
| while (*timeout_ms > 0 && bytes_left > 0) { |
| if (!PollIn(timeout_ms)) { |
| return false; |
| } |
| |
| int result = TEMP_FAILURE_RETRY(recv(socket_, data, bytes_left, MSG_DONTWAIT)); |
| if (result <= 0) { |
| PLOG(ERROR) << "sys_prop: recv error"; |
| return false; |
| } |
| |
| bytes_left -= result; |
| data += result; |
| } |
| |
| if (bytes_left != 0) { |
| LOG(ERROR) << "sys_prop: recv data is not properly obtained."; |
| } |
| |
| return bytes_left == 0; |
| } |
| |
| unique_fd socket_; |
| ucred cred_; |
| |
| DISALLOW_IMPLICIT_CONSTRUCTORS(SocketConnection); |
| }; |
| |
| static uint32_t SendControlMessage(const std::string& msg, const std::string& name, pid_t pid, |
| SocketConnection* socket, std::string* error) { |
| if (init_socket == -1) { |
| *error = "Received control message after shutdown, ignoring"; |
| return PROP_ERROR_HANDLE_CONTROL_MESSAGE; |
| } |
| |
| auto property_msg = PropertyMessage{}; |
| auto* control_message = property_msg.mutable_control_message(); |
| control_message->set_msg(msg); |
| control_message->set_name(name); |
| control_message->set_pid(pid); |
| |
| // We must release the fd before sending it to init, otherwise there will be a race with init. |
| // If init calls close() before Release(), then fdsan will see the wrong tag and abort(). |
| int fd = -1; |
| if (socket != nullptr) { |
| fd = socket->Release(); |
| control_message->set_fd(fd); |
| } |
| |
| if (auto result = SendMessage(init_socket, property_msg); !result) { |
| // We've already released the fd above, so if we fail to send the message to init, we need |
| // to manually free it here. |
| if (fd != -1) { |
| close(fd); |
| } |
| *error = "Failed to send control message: " + result.error().message(); |
| return PROP_ERROR_HANDLE_CONTROL_MESSAGE; |
| } |
| |
| return PROP_SUCCESS; |
| } |
| |
| bool CheckControlPropertyPerms(const std::string& name, const std::string& value, |
| const std::string& source_context, const ucred& cr) { |
| // We check the legacy method first but these properties are dontaudit, so we only log an audit |
| // if the newer method fails as well. We only do this with the legacy ctl. properties. |
| if (name == "ctl.start" || name == "ctl.stop" || name == "ctl.restart") { |
| // The legacy permissions model is that 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_legacy = "ctl." + value; |
| const char* target_context_legacy = nullptr; |
| const char* type_legacy = nullptr; |
| property_info_area->GetPropertyInfo(control_string_legacy.c_str(), &target_context_legacy, |
| &type_legacy); |
| |
| if (CheckMacPerms(control_string_legacy, target_context_legacy, source_context.c_str(), cr)) { |
| return true; |
| } |
| } |
| |
| auto control_string_full = name + "$" + value; |
| const char* target_context_full = nullptr; |
| const char* type_full = nullptr; |
| property_info_area->GetPropertyInfo(control_string_full.c_str(), &target_context_full, |
| &type_full); |
| |
| return CheckMacPerms(control_string_full, target_context_full, source_context.c_str(), cr); |
| } |
| |
| // This returns one of the enum of PROP_SUCCESS or PROP_ERROR*. |
| uint32_t CheckPermissions(const std::string& name, const std::string& value, |
| const std::string& source_context, const ucred& cr, std::string* error) { |
| if (!IsLegalPropertyName(name)) { |
| *error = "Illegal property name"; |
| return PROP_ERROR_INVALID_NAME; |
| } |
| |
| if (StartsWith(name, "ctl.")) { |
| if (!CheckControlPropertyPerms(name, value, source_context, cr)) { |
| *error = StringPrintf("Invalid permissions to perform '%s' on '%s'", name.c_str() + 4, |
| value.c_str()); |
| return PROP_ERROR_HANDLE_CONTROL_MESSAGE; |
| } |
| |
| return PROP_SUCCESS; |
| } |
| |
| 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)) { |
| *error = "SELinux permission check failed"; |
| return PROP_ERROR_PERMISSION_DENIED; |
| } |
| |
| if (type == nullptr || !CheckType(type, value)) { |
| *error = StringPrintf("Property type check failed, value doesn't match expected type '%s'", |
| (type ?: "(null)")); |
| return PROP_ERROR_INVALID_VALUE; |
| } |
| |
| return PROP_SUCCESS; |
| } |
| |
| // This returns one of the enum of PROP_SUCCESS or PROP_ERROR*. |
| uint32_t HandlePropertySet(const std::string& name, const std::string& value, |
| const std::string& source_context, const ucred& cr, |
| SocketConnection* socket, std::string* error) { |
| if (auto ret = CheckPermissions(name, value, source_context, cr, error); ret != PROP_SUCCESS) { |
| return ret; |
| } |
| |
| if (StartsWith(name, "ctl.")) { |
| return SendControlMessage(name.c_str() + 4, value, cr.pid, socket, error); |
| } |
| |
| // 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") { |
| std::string cmdline_path = StringPrintf("proc/%d/cmdline", cr.pid); |
| std::string process_cmdline; |
| std::string process_log_string; |
| if (ReadFileToString(cmdline_path, &process_cmdline)) { |
| // Since cmdline is null deliminated, .c_str() conveniently gives us just the process |
| // path. |
| process_log_string = StringPrintf(" (%s)", process_cmdline.c_str()); |
| } |
| LOG(INFO) << "Received sys.powerctl='" << value << "' from pid: " << cr.pid |
| << process_log_string; |
| } |
| |
| // If a process other than init is writing a non-empty value, it means that process is |
| // requesting that init performs a restorecon operation on the path specified by 'value'. |
| // We use a thread to do this restorecon operation to prevent holding up init, as it may take |
| // a long time to complete. |
| if (name == kRestoreconProperty && cr.pid != 1 && !value.empty()) { |
| static AsyncRestorecon async_restorecon; |
| async_restorecon.TriggerRestorecon(value); |
| return PROP_SUCCESS; |
| } |
| |
| return PropertySet(name, value, error); |
| } |
| |
| uint32_t InitPropertySet(const std::string& name, const std::string& value) { |
| uint32_t result = 0; |
| ucred cr = {.pid = 1, .uid = 0, .gid = 0}; |
| std::string error; |
| result = HandlePropertySet(name, value, kInitContext, cr, nullptr, &error); |
| if (result != PROP_SUCCESS) { |
| LOG(ERROR) << "Init cannot set '" << name << "' to '" << value << "': " << error; |
| } |
| |
| return result; |
| } |
| |
| uint32_t (*property_set)(const std::string& name, const std::string& value) = InitPropertySet; |
| |
| static void handle_property_set_fd() { |
| static constexpr uint32_t kDefaultSocketTimeout = 2000; /* ms */ |
| |
| int s = accept4(property_set_fd, nullptr, nullptr, SOCK_CLOEXEC); |
| if (s == -1) { |
| return; |
| } |
| |
| ucred cr; |
| socklen_t cr_size = sizeof(cr); |
| if (getsockopt(s, SOL_SOCKET, SO_PEERCRED, &cr, &cr_size) < 0) { |
| close(s); |
| PLOG(ERROR) << "sys_prop: unable to get SO_PEERCRED"; |
| return; |
| } |
| |
| SocketConnection socket(s, cr); |
| uint32_t timeout_ms = kDefaultSocketTimeout; |
| |
| uint32_t cmd = 0; |
| if (!socket.RecvUint32(&cmd, &timeout_ms)) { |
| PLOG(ERROR) << "sys_prop: error while reading command from the socket"; |
| socket.SendUint32(PROP_ERROR_READ_CMD); |
| return; |
| } |
| |
| switch (cmd) { |
| case PROP_MSG_SETPROP: { |
| char prop_name[PROP_NAME_MAX]; |
| char prop_value[PROP_VALUE_MAX]; |
| |
| if (!socket.RecvChars(prop_name, PROP_NAME_MAX, &timeout_ms) || |
| !socket.RecvChars(prop_value, PROP_VALUE_MAX, &timeout_ms)) { |
| PLOG(ERROR) << "sys_prop(PROP_MSG_SETPROP): error while reading name/value from the socket"; |
| return; |
| } |
| |
| prop_name[PROP_NAME_MAX-1] = 0; |
| prop_value[PROP_VALUE_MAX-1] = 0; |
| |
| std::string source_context; |
| if (!socket.GetSourceContext(&source_context)) { |
| PLOG(ERROR) << "Unable to set property '" << prop_name << "': getpeercon() failed"; |
| return; |
| } |
| |
| const auto& cr = socket.cred(); |
| std::string error; |
| uint32_t result = |
| HandlePropertySet(prop_name, prop_value, source_context, cr, nullptr, &error); |
| if (result != PROP_SUCCESS) { |
| LOG(ERROR) << "Unable to set property '" << prop_name << "' from uid:" << cr.uid |
| << " gid:" << cr.gid << " pid:" << cr.pid << ": " << error; |
| } |
| |
| break; |
| } |
| |
| case PROP_MSG_SETPROP2: { |
| std::string name; |
| std::string value; |
| if (!socket.RecvString(&name, &timeout_ms) || |
| !socket.RecvString(&value, &timeout_ms)) { |
| PLOG(ERROR) << "sys_prop(PROP_MSG_SETPROP2): error while reading name/value from the socket"; |
| socket.SendUint32(PROP_ERROR_READ_DATA); |
| return; |
| } |
| |
| std::string source_context; |
| if (!socket.GetSourceContext(&source_context)) { |
| PLOG(ERROR) << "Unable to set property '" << name << "': getpeercon() failed"; |
| socket.SendUint32(PROP_ERROR_PERMISSION_DENIED); |
| return; |
| } |
| |
| const auto& cr = socket.cred(); |
| std::string error; |
| uint32_t result = HandlePropertySet(name, value, source_context, cr, &socket, &error); |
| if (result != PROP_SUCCESS) { |
| LOG(ERROR) << "Unable to set property '" << name << "' from uid:" << cr.uid |
| << " gid:" << cr.gid << " pid:" << cr.pid << ": " << error; |
| } |
| socket.SendUint32(result); |
| break; |
| } |
| |
| default: |
| LOG(ERROR) << "sys_prop: invalid command " << cmd; |
| socket.SendUint32(PROP_ERROR_INVALID_CMD); |
| break; |
| } |
| } |
| |
| static bool load_properties_from_file(const char*, const char*, |
| std::map<std::string, std::string>*); |
| |
| /* |
| * Filter is used to decide which properties to load: NULL loads all keys, |
| * "ro.foo.*" is a prefix match, and "ro.foo.bar" is an exact match. |
| */ |
| static void LoadProperties(char* data, const char* filter, const char* filename, |
| std::map<std::string, std::string>* properties) { |
| char *key, *value, *eol, *sol, *tmp, *fn; |
| size_t flen = 0; |
| |
| static constexpr const char* const kVendorPathPrefixes[2] = { |
| "/vendor", |
| "/odm", |
| }; |
| |
| const char* context = kInitContext; |
| if (SelinuxGetVendorAndroidVersion() >= __ANDROID_API_P__) { |
| for (const auto& vendor_path_prefix : kVendorPathPrefixes) { |
| if (StartsWith(filename, vendor_path_prefix)) { |
| context = kVendorContext; |
| } |
| } |
| } |
| |
| if (filter) { |
| flen = strlen(filter); |
| } |
| |
| sol = data; |
| while ((eol = strchr(sol, '\n'))) { |
| key = sol; |
| *eol++ = 0; |
| sol = eol; |
| |
| while (isspace(*key)) key++; |
| if (*key == '#') continue; |
| |
| tmp = eol - 2; |
| while ((tmp > key) && isspace(*tmp)) *tmp-- = 0; |
| |
| if (!strncmp(key, "import ", 7) && flen == 0) { |
| fn = key + 7; |
| while (isspace(*fn)) fn++; |
| |
| key = strchr(fn, ' '); |
| if (key) { |
| *key++ = 0; |
| while (isspace(*key)) key++; |
| } |
| |
| std::string raw_filename(fn); |
| auto expanded_filename = ExpandProps(raw_filename); |
| |
| if (!expanded_filename) { |
| LOG(ERROR) << "Could not expand filename ': " << expanded_filename.error(); |
| continue; |
| } |
| |
| load_properties_from_file(expanded_filename->c_str(), key, properties); |
| } else { |
| value = strchr(key, '='); |
| if (!value) continue; |
| *value++ = 0; |
| |
| tmp = value - 2; |
| while ((tmp > key) && isspace(*tmp)) *tmp-- = 0; |
| |
| while (isspace(*value)) value++; |
| |
| if (flen > 0) { |
| if (filter[flen - 1] == '*') { |
| if (strncmp(key, filter, flen - 1) != 0) continue; |
| } else { |
| if (strcmp(key, filter) != 0) continue; |
| } |
| } |
| |
| if (StartsWith(key, "ctl.") || key == "sys.powerctl"s || |
| std::string{key} == kRestoreconProperty) { |
| LOG(ERROR) << "Ignoring disallowed property '" << key |
| << "' with special meaning in prop file '" << filename << "'"; |
| continue; |
| } |
| |
| ucred cr = {.pid = 1, .uid = 0, .gid = 0}; |
| std::string error; |
| if (CheckPermissions(key, value, context, cr, &error) == PROP_SUCCESS) { |
| auto it = properties->find(key); |
| if (it == properties->end()) { |
| (*properties)[key] = value; |
| } else if (it->second != value) { |
| LOG(WARNING) << "Overriding previous 'ro.' property '" << key << "':'" |
| << it->second << "' with new value '" << value << "'"; |
| it->second = value; |
| } |
| } else { |
| LOG(ERROR) << "Do not have permissions to set '" << key << "' to '" << value |
| << "' in property file '" << filename << "': " << error; |
| } |
| } |
| } |
| } |
| |
| // Filter is used to decide which properties to load: NULL loads all keys, |
| // "ro.foo.*" is a prefix match, and "ro.foo.bar" is an exact match. |
| static bool load_properties_from_file(const char* filename, const char* filter, |
| std::map<std::string, std::string>* properties) { |
| Timer t; |
| auto file_contents = ReadFile(filename); |
| if (!file_contents) { |
| PLOG(WARNING) << "Couldn't load property file '" << filename |
| << "': " << file_contents.error(); |
| return false; |
| } |
| file_contents->push_back('\n'); |
| |
| LoadProperties(file_contents->data(), filter, filename, properties); |
| LOG(VERBOSE) << "(Loading properties from " << filename << " took " << t << ".)"; |
| return true; |
| } |
| |
| // persist.sys.usb.config values can't be combined on build-time when property |
| // files are split into each partition. |
| // So we need to apply the same rule of build/make/tools/post_process_props.py |
| // on runtime. |
| static void update_sys_usb_config() { |
| bool is_debuggable = android::base::GetBoolProperty("ro.debuggable", false); |
| std::string config = android::base::GetProperty("persist.sys.usb.config", ""); |
| if (config.empty()) { |
| property_set("persist.sys.usb.config", is_debuggable ? "adb" : "none"); |
| } else if (is_debuggable && config.find("adb") == std::string::npos && |
| config.length() + 4 < PROP_VALUE_MAX) { |
| config.append(",adb"); |
| property_set("persist.sys.usb.config", config); |
| } |
| } |
| |
| static void load_override_properties() { |
| if (ALLOW_LOCAL_PROP_OVERRIDE) { |
| std::map<std::string, std::string> properties; |
| load_properties_from_file("/data/local.prop", nullptr, &properties); |
| for (const auto& [name, value] : properties) { |
| std::string error; |
| if (PropertySet(name, value, &error) != PROP_SUCCESS) { |
| LOG(ERROR) << "Could not set '" << name << "' to '" << value |
| << "' in /data/local.prop: " << error; |
| } |
| } |
| } |
| } |
| |
| // If the ro.product.[brand|device|manufacturer|model|name] properties have not been explicitly |
| // set, derive them from ro.product.${partition}.* properties |
| static void property_initialize_ro_product_props() { |
| const char* RO_PRODUCT_PROPS_PREFIX = "ro.product."; |
| const char* RO_PRODUCT_PROPS[] = { |
| "brand", "device", "manufacturer", "model", "name", |
| }; |
| const char* RO_PRODUCT_PROPS_ALLOWED_SOURCES[] = { |
| "odm", "product", "system_ext", "system", "vendor", |
| }; |
| const char* RO_PRODUCT_PROPS_DEFAULT_SOURCE_ORDER = "product,odm,vendor,system_ext,system"; |
| const std::string EMPTY = ""; |
| |
| std::string ro_product_props_source_order = |
| GetProperty("ro.product.property_source_order", EMPTY); |
| |
| if (!ro_product_props_source_order.empty()) { |
| // Verify that all specified sources are valid |
| for (const auto& source : Split(ro_product_props_source_order, ",")) { |
| // Verify that the specified source is valid |
| bool is_allowed_source = false; |
| for (const auto& allowed_source : RO_PRODUCT_PROPS_ALLOWED_SOURCES) { |
| if (source == allowed_source) { |
| is_allowed_source = true; |
| break; |
| } |
| } |
| if (!is_allowed_source) { |
| LOG(ERROR) << "Found unexpected source in ro.product.property_source_order; " |
| "using the default property source order"; |
| ro_product_props_source_order = RO_PRODUCT_PROPS_DEFAULT_SOURCE_ORDER; |
| break; |
| } |
| } |
| } else { |
| ro_product_props_source_order = RO_PRODUCT_PROPS_DEFAULT_SOURCE_ORDER; |
| } |
| |
| for (const auto& ro_product_prop : RO_PRODUCT_PROPS) { |
| std::string base_prop(RO_PRODUCT_PROPS_PREFIX); |
| base_prop += ro_product_prop; |
| |
| std::string base_prop_val = GetProperty(base_prop, EMPTY); |
| if (!base_prop_val.empty()) { |
| continue; |
| } |
| |
| for (const auto& source : Split(ro_product_props_source_order, ",")) { |
| std::string target_prop(RO_PRODUCT_PROPS_PREFIX); |
| target_prop += source; |
| target_prop += '.'; |
| target_prop += ro_product_prop; |
| |
| std::string target_prop_val = GetProperty(target_prop, EMPTY); |
| if (!target_prop_val.empty()) { |
| LOG(INFO) << "Setting product property " << base_prop << " to '" << target_prop_val |
| << "' (from " << target_prop << ")"; |
| std::string error; |
| uint32_t res = PropertySet(base_prop, target_prop_val, &error); |
| if (res != PROP_SUCCESS) { |
| LOG(ERROR) << "Error setting product property " << base_prop << ": err=" << res |
| << " (" << error << ")"; |
| } |
| break; |
| } |
| } |
| } |
| } |
| |
| // If the ro.build.fingerprint property has not been set, derive it from constituent pieces |
| static void property_derive_build_fingerprint() { |
| std::string build_fingerprint = GetProperty("ro.build.fingerprint", ""); |
| if (!build_fingerprint.empty()) { |
| return; |
| } |
| |
| const std::string UNKNOWN = "unknown"; |
| build_fingerprint = GetProperty("ro.product.brand", UNKNOWN); |
| build_fingerprint += '/'; |
| build_fingerprint += GetProperty("ro.product.name", UNKNOWN); |
| build_fingerprint += '/'; |
| build_fingerprint += GetProperty("ro.product.device", UNKNOWN); |
| build_fingerprint += ':'; |
| build_fingerprint += GetProperty("ro.build.version.release", UNKNOWN); |
| build_fingerprint += '/'; |
| build_fingerprint += GetProperty("ro.build.id", UNKNOWN); |
| build_fingerprint += '/'; |
| build_fingerprint += GetProperty("ro.build.version.incremental", UNKNOWN); |
| build_fingerprint += ':'; |
| build_fingerprint += GetProperty("ro.build.type", UNKNOWN); |
| build_fingerprint += '/'; |
| build_fingerprint += GetProperty("ro.build.tags", UNKNOWN); |
| |
| LOG(INFO) << "Setting property 'ro.build.fingerprint' to '" << build_fingerprint << "'"; |
| |
| std::string error; |
| uint32_t res = PropertySet("ro.build.fingerprint", build_fingerprint, &error); |
| if (res != PROP_SUCCESS) { |
| LOG(ERROR) << "Error setting property 'ro.build.fingerprint': err=" << res << " (" << error |
| << ")"; |
| } |
| } |
| |
| void property_load_boot_defaults(bool load_debug_prop) { |
| // TODO(b/117892318): merge prop.default and build.prop files into one |
| // We read the properties and their values into a map, in order to always allow properties |
| // loaded in the later property files to override the properties in loaded in the earlier |
| // property files, regardless of if they are "ro." properties or not. |
| std::map<std::string, std::string> properties; |
| if (!load_properties_from_file("/system/etc/prop.default", nullptr, &properties)) { |
| // Try recovery path |
| if (!load_properties_from_file("/prop.default", nullptr, &properties)) { |
| // Try legacy path |
| load_properties_from_file("/default.prop", nullptr, &properties); |
| } |
| } |
| load_properties_from_file("/system/build.prop", nullptr, &properties); |
| load_properties_from_file("/system_ext/build.prop", nullptr, &properties); |
| load_properties_from_file("/vendor/default.prop", nullptr, &properties); |
| load_properties_from_file("/vendor/build.prop", nullptr, &properties); |
| if (SelinuxGetVendorAndroidVersion() >= __ANDROID_API_Q__) { |
| load_properties_from_file("/odm/etc/build.prop", nullptr, &properties); |
| } else { |
| load_properties_from_file("/odm/default.prop", nullptr, &properties); |
| load_properties_from_file("/odm/build.prop", nullptr, &properties); |
| } |
| load_properties_from_file("/product/build.prop", nullptr, &properties); |
| load_properties_from_file("/factory/factory.prop", "ro.*", &properties); |
| |
| if (load_debug_prop) { |
| LOG(INFO) << "Loading " << kDebugRamdiskProp; |
| load_properties_from_file(kDebugRamdiskProp, nullptr, &properties); |
| } |
| |
| for (const auto& [name, value] : properties) { |
| std::string error; |
| if (PropertySet(name, value, &error) != PROP_SUCCESS) { |
| LOG(ERROR) << "Could not set '" << name << "' to '" << value |
| << "' while loading .prop files" << error; |
| } |
| } |
| |
| property_initialize_ro_product_props(); |
| property_derive_build_fingerprint(); |
| |
| update_sys_usb_config(); |
| } |
| |
| bool LoadPropertyInfoFromFile(const std::string& filename, |
| std::vector<PropertyInfoEntry>* property_infos) { |
| auto file_contents = std::string(); |
| if (!ReadFileToString(filename, &file_contents)) { |
| PLOG(ERROR) << "Could not read properties from '" << filename << "'"; |
| return false; |
| } |
| |
| auto errors = std::vector<std::string>{}; |
| ParsePropertyInfoFile(file_contents, property_infos, &errors); |
| // Individual parsing errors are reported but do not cause a failed boot, which is what |
| // returning false would do here. |
| for (const auto& error : errors) { |
| LOG(ERROR) << "Could not read line from '" << filename << "': " << error; |
| } |
| |
| return true; |
| } |
| |
| void CreateSerializedPropertyInfo() { |
| auto property_infos = std::vector<PropertyInfoEntry>(); |
| if (access("/system/etc/selinux/plat_property_contexts", R_OK) != -1) { |
| if (!LoadPropertyInfoFromFile("/system/etc/selinux/plat_property_contexts", |
| &property_infos)) { |
| return; |
| } |
| // Don't check for failure here, so we always have a sane list of properties. |
| // E.g. In case of recovery, the vendor partition will not have mounted and we |
| // still need the system / platform properties to function. |
| if (!LoadPropertyInfoFromFile("/vendor/etc/selinux/vendor_property_contexts", |
| &property_infos)) { |
| // Fallback to nonplat_* if vendor_* doesn't exist. |
| LoadPropertyInfoFromFile("/vendor/etc/selinux/nonplat_property_contexts", |
| &property_infos); |
| } |
| if (access("/product/etc/selinux/product_property_contexts", R_OK) != -1) { |
| LoadPropertyInfoFromFile("/product/etc/selinux/product_property_contexts", |
| &property_infos); |
| } |
| if (access("/odm/etc/selinux/odm_property_contexts", R_OK) != -1) { |
| LoadPropertyInfoFromFile("/odm/etc/selinux/odm_property_contexts", &property_infos); |
| } |
| } else { |
| if (!LoadPropertyInfoFromFile("/plat_property_contexts", &property_infos)) { |
| return; |
| } |
| if (!LoadPropertyInfoFromFile("/vendor_property_contexts", &property_infos)) { |
| // Fallback to nonplat_* if vendor_* doesn't exist. |
| LoadPropertyInfoFromFile("/nonplat_property_contexts", &property_infos); |
| } |
| LoadPropertyInfoFromFile("/product_property_contexts", &property_infos); |
| LoadPropertyInfoFromFile("/odm_property_contexts", &property_infos); |
| } |
| |
| auto serialized_contexts = std::string(); |
| auto error = std::string(); |
| if (!BuildTrie(property_infos, "u:object_r:default_prop:s0", "string", &serialized_contexts, |
| &error)) { |
| LOG(ERROR) << "Unable to serialize property contexts: " << error; |
| return; |
| } |
| |
| constexpr static const char kPropertyInfosPath[] = "/dev/__properties__/property_info"; |
| if (!WriteStringToFile(serialized_contexts, kPropertyInfosPath, 0444, 0, 0, false)) { |
| PLOG(ERROR) << "Unable to write serialized property infos to file"; |
| } |
| selinux_android_restorecon(kPropertyInfosPath, 0); |
| } |
| |
| static void HandleInitSocket() { |
| auto message = ReadMessage(init_socket); |
| if (!message) { |
| LOG(ERROR) << "Could not read message from init_dedicated_recv_socket: " << message.error(); |
| return; |
| } |
| |
| auto init_message = InitMessage{}; |
| if (!init_message.ParseFromString(*message)) { |
| LOG(ERROR) << "Could not parse message from init"; |
| return; |
| } |
| |
| switch (init_message.msg_case()) { |
| case InitMessage::kLoadPersistentProperties: { |
| load_override_properties(); |
| // Read persistent properties after all default values have been loaded. |
| auto persistent_properties = LoadPersistentProperties(); |
| for (const auto& persistent_property_record : persistent_properties.properties()) { |
| InitPropertySet(persistent_property_record.name(), |
| persistent_property_record.value()); |
| } |
| InitPropertySet("ro.persistent_properties.ready", "true"); |
| persistent_properties_loaded = true; |
| break; |
| } |
| case InitMessage::kStopSendingMessages: { |
| init_socket = -1; |
| break; |
| } |
| default: |
| LOG(ERROR) << "Unknown message type from init: " << init_message.msg_case(); |
| } |
| } |
| |
| static void PropertyServiceThread() { |
| Epoll epoll; |
| if (auto result = epoll.Open(); !result) { |
| LOG(FATAL) << result.error(); |
| } |
| |
| if (auto result = epoll.RegisterHandler(property_set_fd, handle_property_set_fd); !result) { |
| LOG(FATAL) << result.error(); |
| } |
| |
| if (auto result = epoll.RegisterHandler(init_socket, HandleInitSocket); !result) { |
| LOG(FATAL) << result.error(); |
| } |
| |
| while (true) { |
| auto pending_functions = epoll.Wait(std::nullopt); |
| if (!pending_functions) { |
| LOG(ERROR) << pending_functions.error(); |
| } else { |
| for (const auto& function : *pending_functions) { |
| (*function)(); |
| } |
| } |
| } |
| } |
| |
| void StartPropertyService(int* epoll_socket) { |
| property_set("ro.property_service.version", "2"); |
| |
| int sockets[2]; |
| if (socketpair(AF_UNIX, SOCK_SEQPACKET | SOCK_CLOEXEC, 0, sockets) != 0) { |
| PLOG(FATAL) << "Failed to socketpair() between property_service and init"; |
| } |
| *epoll_socket = sockets[0]; |
| init_socket = sockets[1]; |
| |
| if (auto result = CreateSocket(PROP_SERVICE_NAME, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, |
| false, 0666, 0, 0, {})) { |
| property_set_fd = *result; |
| } else { |
| LOG(FATAL) << "start_property_service socket creation failed: " << result.error(); |
| } |
| |
| listen(property_set_fd, 8); |
| |
| std::thread{PropertyServiceThread}.detach(); |
| |
| property_set = [](const std::string& key, const std::string& value) -> uint32_t { |
| android::base::SetProperty(key, value); |
| return 0; |
| }; |
| } |
| |
| } // namespace init |
| } // namespace android |