/*
* Copyright (C) 2016 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 "otautil/logging.h"
#include <dirent.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <sys/klog.h>
#include <sys/types.h>
#include <algorithm>
#include <memory>
#include <string>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/parseint.h>
#include <android-base/stringprintf.h>
#include <android-base/unique_fd.h>
#include <private/android_filesystem_config.h> /* for AID_SYSTEM */
#include <private/android_logger.h> /* private pmsg functions */
#include <selinux/label.h>
#include "otautil/dirutil.h"
#include "otautil/paths.h"
#include "otautil/roots.h"
constexpr const char* LOG_FILE = "/cache/recovery/log";
constexpr const char* LAST_INSTALL_FILE = "/cache/recovery/last_install";
constexpr const char* LAST_KMSG_FILE = "/cache/recovery/last_kmsg";
constexpr const char* LAST_LOG_FILE = "/cache/recovery/last_log";
constexpr const char* LAST_KMSG_FILTER = "recovery/last_kmsg";
constexpr const char* LAST_LOG_FILTER = "recovery/last_log";
constexpr const char* CACHE_LOG_DIR = "/cache/recovery";
static struct selabel_handle* logging_sehandle;
void SetLoggingSehandle(selabel_handle* handle) {
logging_sehandle = handle;
}
// fopen(3)'s the given file, by mounting volumes and making parent dirs as necessary. Returns the
// file pointer, or nullptr on error.
static FILE* fopen_path(const std::string& path, const char* mode, const selabel_handle* sehandle) {
if (ensure_path_mounted(path) != 0) {
LOG(ERROR) << "Can't mount " << path;
return nullptr;
}
// When writing, try to create the containing directory, if necessary. Use generous permissions,
// the system (init.rc) will reset them.
if (strchr("wa", mode[0])) {
mkdir_recursively(path, 0777, true, sehandle);
}
return fopen(path.c_str(), mode);
}
void check_and_fclose(FILE* fp, const std::string& name) {
fflush(fp);
if (fsync(fileno(fp)) == -1) {
PLOG(ERROR) << "Failed to fsync " << name;
}
if (ferror(fp)) {
PLOG(ERROR) << "Error in " << name;
}
fclose(fp);
}
// close a file, log an error if the error indicator is set
ssize_t logbasename(log_id_t /* id */, char /* prio */, const char* filename, const char* /* buf */,
size_t len, void* arg) {
bool* do_rotate = static_cast<bool*>(arg);
if (std::string(LAST_KMSG_FILTER).find(filename) != std::string::npos ||
std::string(LAST_LOG_FILTER).find(filename) != std::string::npos) {
*do_rotate = true;
}
return len;
}
ssize_t logrotate(log_id_t id, char prio, const char* filename, const char* buf, size_t len,
void* arg) {
bool* do_rotate = static_cast<bool*>(arg);
if (!*do_rotate) {
return __android_log_pmsg_file_write(id, prio, filename, buf, len);
}
std::string name(filename);
size_t dot = name.find_last_of('.');
std::string sub = name.substr(0, dot);
if (std::string(LAST_KMSG_FILTER).find(sub) == std::string::npos &&
std::string(LAST_LOG_FILTER).find(sub) == std::string::npos) {
return __android_log_pmsg_file_write(id, prio, filename, buf, len);
}
// filename rotation
if (dot == std::string::npos) {
name += ".1";
} else {
std::string number = name.substr(dot + 1);
if (!isdigit(number[0])) {
name += ".1";
} else {
size_t i;
if (!android::base::ParseUint(number, &i)) {
LOG(ERROR) << "failed to parse uint in " << number;
return -1;
}
name = sub + "." + std::to_string(i + 1);
}
}
return __android_log_pmsg_file_write(id, prio, name.c_str(), buf, len);
}
// Rename last_log -> last_log.1 -> last_log.2 -> ... -> last_log.$max.
// Similarly rename last_kmsg -> last_kmsg.1 -> ... -> last_kmsg.$max.
// Overwrite any existing last_log.$max and last_kmsg.$max.
void rotate_logs(const char* last_log_file, const char* last_kmsg_file) {
// Logs should only be rotated once.
static bool rotated = false;
if (rotated) {
return;
}
rotated = true;
for (int i = KEEP_LOG_COUNT - 1; i >= 0; --i) {
std::string old_log = android::base::StringPrintf("%s", last_log_file);
if (i > 0) {
old_log += "." + std::to_string(i);
}
std::string new_log = android::base::StringPrintf("%s.%d", last_log_file, i + 1);
// Ignore errors if old_log doesn't exist.
rename(old_log.c_str(), new_log.c_str());
std::string old_kmsg = android::base::StringPrintf("%s", last_kmsg_file);
if (i > 0) {
old_kmsg += "." + std::to_string(i);
}
std::string new_kmsg = android::base::StringPrintf("%s.%d", last_kmsg_file, i + 1);
rename(old_kmsg.c_str(), new_kmsg.c_str());
}
}
// Writes content to the current pmsg session.
static ssize_t __pmsg_write(const std::string& filename, const std::string& buf) {
return __android_log_pmsg_file_write(LOG_ID_SYSTEM, ANDROID_LOG_INFO, filename.c_str(),
buf.data(), buf.size());
}
void copy_log_file_to_pmsg(const std::string& source, const std::string& destination) {
std::string content;
android::base::ReadFileToString(source, &content);
__pmsg_write(destination, content);
}
// How much of the temp log we have copied to the copy in cache.
static off_t tmplog_offset = 0;
void reset_tmplog_offset() {
tmplog_offset = 0;
}
static void copy_log_file(const std::string& source, const std::string& destination, bool append) {
FILE* dest_fp = fopen_path(destination, append ? "ae" : "we", logging_sehandle);
if (dest_fp == nullptr) {
PLOG(ERROR) << "Can't open " << destination;
} else {
FILE* source_fp = fopen(source.c_str(), "re");
if (source_fp != nullptr) {
if (append) {
fseeko(source_fp, tmplog_offset, SEEK_SET); // Since last write
}
char buf[4096];
size_t bytes;
while ((bytes = fread(buf, 1, sizeof(buf), source_fp)) != 0) {
fwrite(buf, 1, bytes, dest_fp);
}
if (append) {
tmplog_offset = ftello(source_fp);
}
check_and_fclose(source_fp, source);
}
check_and_fclose(dest_fp, destination);
}
}
void copy_logs(bool save_current_log) {
// We only rotate and record the log of the current session if explicitly requested. This usually
// happens after wipes, installation from BCB or menu selections. This is to avoid unnecessary
// rotation (and possible deletion) of log files, if it does not do anything loggable.
if (!save_current_log) {
return;
}
// Always write to pmsg, this allows the OTA logs to be caught in `logcat -L`.
copy_log_file_to_pmsg(Paths::Get().temporary_log_file(), LAST_LOG_FILE);
copy_log_file_to_pmsg(Paths::Get().temporary_install_file(), LAST_INSTALL_FILE);
// We can do nothing for now if there's no /cache partition.
if (!HasCache()) {
return;
}
ensure_path_mounted(LAST_LOG_FILE);
ensure_path_mounted(LAST_KMSG_FILE);
rotate_logs(LAST_LOG_FILE, LAST_KMSG_FILE);
// Copy logs to cache so the system can find out what happened.
copy_log_file(Paths::Get().temporary_log_file(), LOG_FILE, true);
copy_log_file(Paths::Get().temporary_log_file(), LAST_LOG_FILE, false);
copy_log_file(Paths::Get().temporary_install_file(), LAST_INSTALL_FILE, false);
save_kernel_log(LAST_KMSG_FILE);
chmod(LOG_FILE, 0600);
chown(LOG_FILE, AID_SYSTEM, AID_SYSTEM);
chmod(LAST_KMSG_FILE, 0600);
chown(LAST_KMSG_FILE, AID_SYSTEM, AID_SYSTEM);
chmod(LAST_LOG_FILE, 0640);
chmod(LAST_INSTALL_FILE, 0644);
chown(LAST_INSTALL_FILE, AID_SYSTEM, AID_SYSTEM);
sync();
}
// Read from kernel log into buffer and write out to file.
void save_kernel_log(const char* destination) {
int klog_buf_len = klogctl(KLOG_SIZE_BUFFER, 0, 0);
if (klog_buf_len <= 0) {
PLOG(ERROR) << "Error getting klog size";
return;
}
std::string buffer(klog_buf_len, 0);
int n = klogctl(KLOG_READ_ALL, &buffer[0], klog_buf_len);
if (n == -1) {
PLOG(ERROR) << "Error in reading klog";
return;
}
buffer.resize(n);
android::base::WriteStringToFile(buffer, destination);
}
std::vector<saved_log_file> ReadLogFilesToMemory() {
ensure_path_mounted("/cache");
struct dirent* de;
std::unique_ptr<DIR, decltype(&closedir)> d(opendir(CACHE_LOG_DIR), closedir);
if (!d) {
if (errno != ENOENT) {
PLOG(ERROR) << "Failed to opendir " << CACHE_LOG_DIR;
}
return {};
}
std::vector<saved_log_file> log_files;
while ((de = readdir(d.get())) != nullptr) {
if (strncmp(de->d_name, "last_", 5) == 0 || strcmp(de->d_name, "log") == 0) {
std::string path = android::base::StringPrintf("%s/%s", CACHE_LOG_DIR, de->d_name);
struct stat sb;
if (stat(path.c_str(), &sb) != 0) {
PLOG(ERROR) << "Failed to stat " << path;
continue;
}
// Truncate files to 512kb
size_t read_size = std::min<size_t>(sb.st_size, 1 << 19);
std::string data(read_size, '\0');
android::base::unique_fd log_fd(TEMP_FAILURE_RETRY(open(path.c_str(), O_RDONLY)));
if (log_fd == -1 || !android::base::ReadFully(log_fd, data.data(), read_size)) {
PLOG(ERROR) << "Failed to read log file " << path;
continue;
}
log_files.emplace_back(saved_log_file{ path, sb, data });
}
}
return log_files;
}
bool RestoreLogFilesAfterFormat(const std::vector<saved_log_file>& log_files) {
// Re-create the log dir and write back the log entries.
if (ensure_path_mounted(CACHE_LOG_DIR) != 0) {
PLOG(ERROR) << "Failed to mount " << CACHE_LOG_DIR;
return false;
}
if (mkdir_recursively(CACHE_LOG_DIR, 0777, false, logging_sehandle) != 0) {
PLOG(ERROR) << "Failed to create " << CACHE_LOG_DIR;
return false;
}
for (const auto& log : log_files) {
if (!android::base::WriteStringToFile(log.data, log.name, log.sb.st_mode, log.sb.st_uid,
log.sb.st_gid)) {
PLOG(ERROR) << "Failed to write to " << log.name;
}
}
// Any part of the log we'd copied to cache is now gone.
// Reset the pointer so we copy from the beginning of the temp
// log.
reset_tmplog_offset();
copy_logs(true /* save_current_log */);
return true;
}
