/*
* Copyright (C) 2012 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 "install/adb_install.h"
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <sys/epoll.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <atomic>
#include <functional>
#include <map>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/memory.h>
#include <android-base/properties.h>
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
#include "fuse_sideload.h"
#include "install/install.h"
#include "minadbd_types.h"
#include "recovery_ui/ui.h"
using CommandFunction = std::function<bool()>;
static bool SetUsbConfig(const std::string& state) {
android::base::SetProperty("sys.usb.config", state);
return android::base::WaitForProperty("sys.usb.state", state);
}
// Parses the minadbd command in |message|; returns MinadbdCommands::kError upon errors.
static MinadbdCommands ParseMinadbdCommands(const std::string& message) {
if (!android::base::StartsWith(message, kMinadbdCommandPrefix)) {
LOG(ERROR) << "Failed to parse command in message " << message;
return MinadbdCommands::kError;
}
auto cmd_code_string = message.substr(strlen(kMinadbdCommandPrefix));
auto cmd_code = android::base::get_unaligned<uint32_t>(cmd_code_string.c_str());
if (cmd_code >= static_cast<uint32_t>(MinadbdCommands::kError)) {
LOG(ERROR) << "Unsupported command code: " << cmd_code;
return MinadbdCommands::kError;
}
return static_cast<MinadbdCommands>(cmd_code);
}
static bool WriteStatusToFd(MinadbdCommandStatus status, int fd) {
char message[kMinadbdMessageSize];
memcpy(message, kMinadbdStatusPrefix, strlen(kMinadbdStatusPrefix));
android::base::put_unaligned(message + strlen(kMinadbdStatusPrefix), status);
if (!android::base::WriteFully(fd, message, kMinadbdMessageSize)) {
PLOG(ERROR) << "Failed to write message " << message;
return false;
}
return true;
}
// Installs the package from FUSE. Returns true if the installation succeeds, and false otherwise.
static bool AdbInstallPackageHandler(bool* wipe_cache, RecoveryUI* ui, int* result) {
// How long (in seconds) we wait for the package path to be ready. It doesn't need to be too long
// because the minadbd service has already issued an install command. FUSE_SIDELOAD_HOST_PATHNAME
// will start to exist once the host connects and starts serving a package. Poll for its
// appearance. (Note that inotify doesn't work with FUSE.)
constexpr int ADB_INSTALL_TIMEOUT = 15;
*result = INSTALL_ERROR;
for (int i = 0; i < ADB_INSTALL_TIMEOUT; ++i) {
struct stat st;
if (stat(FUSE_SIDELOAD_HOST_PATHNAME, &st) != 0) {
if (errno == ENOENT && i < ADB_INSTALL_TIMEOUT - 1) {
sleep(1);
continue;
} else {
ui->Print("\nTimed out waiting for fuse to be ready.\n\n");
break;
}
}
*result = install_package(FUSE_SIDELOAD_HOST_PATHNAME, wipe_cache, false, 0, ui);
break;
}
// Calling stat() on this magic filename signals the FUSE to exit.
struct stat st;
stat(FUSE_SIDELOAD_HOST_EXIT_PATHNAME, &st);
return *result == INSTALL_SUCCESS;
}
// Parses and executes the command from minadbd. Returns false if we enter an invalid state so that
// the caller can kill the minadbd service properly.
static bool HandleMessageFromMinadbd(
int socket_fd, const std::map<MinadbdCommands, CommandFunction>& command_map) {
char buffer[kMinadbdMessageSize];
if (!android::base::ReadFully(socket_fd, buffer, kMinadbdMessageSize)) {
PLOG(ERROR) << "Failed to read message from minadbd";
return false;
}
std::string message(buffer, buffer + kMinadbdMessageSize);
auto command_type = ParseMinadbdCommands(message);
if (command_type == MinadbdCommands::kError) {
return false;
}
if (command_map.find(command_type) == command_map.end()) {
LOG(ERROR) << "Unsupported command: "
<< android::base::get_unaligned<unsigned int>(
message.substr(strlen(kMinadbdCommandPrefix)).c_str());
return false;
}
// We have received a valid command, execute the corresponding function.
const auto& command_func = command_map.at(command_type);
if (!command_func()) {
LOG(ERROR) << "Failed to execute command " << static_cast<unsigned int>(command_type);
return WriteStatusToFd(MinadbdCommandStatus::kFailure, socket_fd);
}
return WriteStatusToFd(MinadbdCommandStatus::kSuccess, socket_fd);
}
// TODO(xunchang) add a wrapper function and kill the minadbd service there.
static void ListenAndExecuteMinadbdCommands(
pid_t minadbd_pid, android::base::unique_fd&& socket_fd,
const std::map<MinadbdCommands, CommandFunction>& command_map) {
android::base::unique_fd epoll_fd(epoll_create1(O_CLOEXEC));
if (epoll_fd == -1) {
PLOG(ERROR) << "Failed to create epoll";
kill(minadbd_pid, SIGKILL);
return;
}
constexpr int EPOLL_MAX_EVENTS = 10;
struct epoll_event ev = {};
ev.events = EPOLLIN | EPOLLHUP;
ev.data.fd = socket_fd.get();
struct epoll_event events[EPOLL_MAX_EVENTS];
if (epoll_ctl(epoll_fd.get(), EPOLL_CTL_ADD, socket_fd.get(), &ev) == -1) {
PLOG(ERROR) << "Failed to add socket fd to epoll";
kill(minadbd_pid, SIGKILL);
return;
}
// Set the timeout to be 300s when waiting for minadbd commands.
constexpr int TIMEOUT_MILLIS = 300 * 1000;
while (true) {
// Poll for the status change of the socket_fd, and handle the message if the fd is ready to
// read.
int event_count =
TEMP_FAILURE_RETRY(epoll_wait(epoll_fd.get(), events, EPOLL_MAX_EVENTS, TIMEOUT_MILLIS));
if (event_count == -1) {
PLOG(ERROR) << "Failed to wait for epoll events";
kill(minadbd_pid, SIGKILL);
return;
}
if (event_count == 0) {
LOG(ERROR) << "Timeout waiting for messages from minadbd";
kill(minadbd_pid, SIGKILL);
return;
}
for (int n = 0; n < event_count; n++) {
if (events[n].events & EPOLLHUP) {
LOG(INFO) << "Socket has been closed";
kill(minadbd_pid, SIGKILL);
return;
}
if (!HandleMessageFromMinadbd(socket_fd.get(), command_map)) {
kill(minadbd_pid, SIGKILL);
return;
}
}
}
}
// Recovery starts minadbd service as a child process, and spawns another thread to listen for the
// message from minadbd through a socket pair. Here is an example to execute one command from adb
// host.
// a. recovery b. listener thread c. minadbd service
//
// a1. create socket pair
// a2. fork minadbd service
// c3. wait for the adb commands
// from host
// c4. after receiving host commands:
// 1) set up pre-condition (i.e.
// start fuse for adb sideload)
// 2) issue command through
// socket.
// 3) wait for result
// a5. start listener thread
// b6. listen for message from
// minadbd in a loop.
// b7. After receiving a minadbd
// command from socket
// 1) execute the command function
// 2) send the result back to
// minadbd
// ......
// c8. exit upon receiving the
// result
// a9. wait for listener thread
// to exit.
//
// a10. wait for minadbd to
// exit
// b11. exit the listening loop
//
static void CreateMinadbdServiceAndExecuteCommands(
const std::map<MinadbdCommands, CommandFunction>& command_map) {
signal(SIGPIPE, SIG_IGN);
android::base::unique_fd recovery_socket;
android::base::unique_fd minadbd_socket;
if (!android::base::Socketpair(AF_UNIX, SOCK_STREAM, 0, &recovery_socket, &minadbd_socket)) {
PLOG(ERROR) << "Failed to create socket";
return;
}
pid_t child = fork();
if (child == -1) {
PLOG(ERROR) << "Failed to fork child process";
return;
}
if (child == 0) {
recovery_socket.reset();
execl("/system/bin/minadbd", "minadbd", "--socket_fd",
std::to_string(minadbd_socket.release()).c_str(), nullptr);
_exit(EXIT_FAILURE);
}
minadbd_socket.reset();
// We need to call SetUsbConfig() after forking minadbd service. Because the function waits for
// the usb state to be updated, which depends on sys.usb.ffs.ready=1 set in the adb daemon.
if (!SetUsbConfig("sideload")) {
LOG(ERROR) << "Failed to set usb config to sideload";
return;
}
std::thread listener_thread(ListenAndExecuteMinadbdCommands, child, std::move(recovery_socket),
std::ref(command_map));
if (listener_thread.joinable()) {
listener_thread.join();
}
int status;
waitpid(child, &status, 0);
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
if (WEXITSTATUS(status) == MinadbdErrorCode::kMinadbdAdbVersionError) {
LOG(ERROR) << "\nYou need adb 1.0.32 or newer to sideload\nto this device.\n";
} else if (!WIFSIGNALED(status)) {
LOG(ERROR) << "\n(adbd status " << WEXITSTATUS(status) << ")";
}
}
signal(SIGPIPE, SIG_DFL);
}
int apply_from_adb(bool* wipe_cache, RecoveryUI* ui) {
// Save the usb state to restore after the sideload operation.
std::string usb_state = android::base::GetProperty("sys.usb.state", "none");
// Clean up state and stop adbd.
if (usb_state != "none" && !SetUsbConfig("none")) {
LOG(ERROR) << "Failed to clear USB config";
return INSTALL_ERROR;
}
ui->Print(
"\n\nNow send the package you want to apply\n"
"to the device with \"adb sideload <filename>\"...\n");
int install_result = INSTALL_ERROR;
std::map<MinadbdCommands, CommandFunction> command_map{
{ MinadbdCommands::kInstall,
std::bind(&AdbInstallPackageHandler, wipe_cache, ui, &install_result) },
};
CreateMinadbdServiceAndExecuteCommands(command_map);
// Clean up before switching to the older state, for example setting the state
// to none sets sys/class/android_usb/android0/enable to 0.
if (!SetUsbConfig("none")) {
LOG(ERROR) << "Failed to clear USB config";
}
if (usb_state != "none") {
if (!SetUsbConfig(usb_state)) {
LOG(ERROR) << "Failed to set USB config to " << usb_state;
}
}
return install_result;
}
