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Implement logging purely in Rust

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This commit is contained in:
topjohnwu 2023-05-09 18:54:38 -07:00
parent 8c2ad3883a
commit 7518092ad2
17 changed files with 433 additions and 228 deletions
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1
native/src/Android.mk
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@ -29,7 +29,6 @@ LOCAL_SRC_FILES := \
core/scripting.cpp \
core/restorecon.cpp \
core/module.cpp \
core/logging.cpp \
core/thread.cpp \
resetprop/persist.cpp \
resetprop/resetprop.cpp \

37
native/src/Cargo.lock generated
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@ -75,7 +75,7 @@ version = "1.0.94"
dependencies = [
"proc-macro2",
"quote",
"syn",
"syn 2.0.15",
]
[[package]]
@ -183,6 +183,8 @@ version = "0.0.0"
dependencies = [
"base",
"cxx",
"num-derive",
"num-traits",
]
[[package]]
@ -217,6 +219,26 @@ version = "2.5.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
[[package]]
name = "num-derive"
version = "0.3.3"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "876a53fff98e03a936a674b29568b0e605f06b29372c2489ff4de23f1949743d"
dependencies = [
"proc-macro2",
"quote",
"syn 1.0.109",
]
[[package]]
name = "num-traits"
version = "0.2.15"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "578ede34cf02f8924ab9447f50c28075b4d3e5b269972345e7e0372b38c6cdcd"
dependencies = [
"autocfg",
]
[[package]]
name = "once_cell"
version = "1.17.1"
@ -332,6 +354,17 @@ dependencies = [
"windows-sys 0.48.0",
]
[[package]]
name = "syn"
version = "1.0.109"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "72b64191b275b66ffe2469e8af2c1cfe3bafa67b529ead792a6d0160888b4237"
dependencies = [
"proc-macro2",
"quote",
"unicode-ident",
]
[[package]]
name = "syn"
version = "2.0.15"
@ -373,7 +406,7 @@ checksum = "f9456a42c5b0d803c8cd86e73dd7cc9edd429499f37a3550d286d5e86720569f"
dependencies = [
"proc-macro2",
"quote",
"syn",
"syn 2.0.15",
]
[[package]]

9
native/src/base/consts.rs Normal file
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@ -0,0 +1,9 @@
// We expose constant values as macros so that all constants are literals
// An advantage for doing this is that we can use concat!() on these values
#[macro_export]
macro_rules! LOGFILE {
() => {
"/cache/magisk.log"
};
}

2
native/src/base/lib.rs
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@ -2,11 +2,13 @@
pub use libc;
pub use consts::*;
pub use files::*;
pub use logging::*;
pub use misc::*;
pub use xwrap::*;
mod consts;
mod files;
mod logging;
mod misc;

2
native/src/base/misc.hpp
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@ -130,7 +130,7 @@ uint64_t parse_uint64_hex(std::string_view s);
int parse_int(std::string_view s);
using thread_entry = void *(*)(void *);
int new_daemon_thread(thread_entry entry, void *arg = nullptr);
extern "C" int new_daemon_thread(thread_entry entry, void *arg = nullptr);
static inline bool str_contains(std::string_view s, std::string_view ss) {
return s.find(ss) != std::string::npos;

21
native/src/base/misc.rs
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@ -151,3 +151,24 @@ pub unsafe fn slice_from_ptr_mut<'a, T>(buf: *mut T, len: usize) -> &'a mut [T]
slice::from_raw_parts_mut(buf, len)
}
}
pub trait FlatData {
fn as_raw_bytes(&self) -> &[u8]
where
Self: Sized,
{
unsafe {
let self_ptr = self as *const Self as *const u8;
slice::from_raw_parts(self_ptr, std::mem::size_of::<Self>())
}
}
fn as_raw_bytes_mut(&mut self) -> &mut [u8]
where
Self: Sized,
{
unsafe {
let self_ptr = self as *mut Self as *mut u8;
slice::from_raw_parts_mut(self_ptr, std::mem::size_of::<Self>())
}
}
}

2
native/src/core/Cargo.toml
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@ -10,3 +10,5 @@ path = "lib.rs"
[dependencies]
base = { path = "../base" }
cxx = { path = "../external/cxx-rs" }
num-traits = "0.2"
num-derive = "0.3"

6
native/src/core/bootstages.cpp
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@ -373,7 +373,7 @@ static void post_fs_data() {
if (!check_data())
return;
setup_logfile(true);
rust::get_magiskd().setup_logfile();
LOGI("** post-fs-data mode running\n");
@ -413,7 +413,7 @@ early_abort:
}
static void late_start() {
setup_logfile(false);
rust::get_magiskd().setup_logfile();
LOGI("** late_start service mode running\n");
@ -425,7 +425,7 @@ static void late_start() {
static void boot_complete() {
boot_state |= FLAG_BOOT_COMPLETE;
setup_logfile(false);
rust::get_magiskd().setup_logfile();
LOGI("** boot-complete triggered\n");

2
native/src/core/core.hpp
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@ -9,8 +9,6 @@ extern std::atomic<ino_t> pkg_xml_ino;
std::string find_preinit_device();
void unlock_blocks();
void reboot();
void start_log_daemon();
void setup_logfile(bool reset);
std::string read_certificate(int fd, int version = -1);
// Module stuffs

6
native/src/core/daemon.cpp
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@ -186,7 +186,7 @@ static void handle_request_sync(int client, int code) {
write_string(client, MAGISKTMP.data());
break;
case MainRequest::START_DAEMON:
setup_logfile(true);
rust::get_magiskd().setup_logfile();
break;
case MainRequest::STOP_DAEMON:
denylist_handler(-1, nullptr);
@ -298,7 +298,7 @@ static void switch_cgroup(const char *cgroup, int pid) {
}
static void daemon_entry() {
magisk_logging();
android_logging();
// Block all signals
sigset_t block_set;
@ -321,7 +321,7 @@ static void daemon_entry() {
setsid();
setcon(MAGISK_PROC_CON);
start_log_daemon();
rust::daemon_entry();
LOGI(NAME_WITH_VER(Magisk) " daemon started\n");

31
native/src/core/daemon.rs Normal file
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@ -0,0 +1,31 @@
use crate::logging::{magisk_logging, zygisk_logging};
use std::cell::RefCell;
use std::fs::File;
use std::sync::{Mutex, OnceLock};
// Global magiskd singleton
pub static MAGISKD: OnceLock<MagiskD> = OnceLock::new();
#[derive(Default)]
pub struct MagiskD {
pub logd: Mutex<RefCell<Option<File>>>,
}
pub fn daemon_entry() {
let magiskd = MagiskD::default();
magiskd.start_log_daemon();
MAGISKD.set(magiskd).ok();
magisk_logging();
}
pub fn zygisk_entry() {
let magiskd = MagiskD::default();
MAGISKD.set(magiskd).ok();
zygisk_logging();
}
pub fn get_magiskd() -> &'static MagiskD {
MAGISKD.get().unwrap()
}
impl MagiskD {}

16
native/src/core/lib.rs
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@ -1,6 +1,8 @@
pub use base;
use daemon::*;
use logging::*;
mod daemon;
mod logging;
#[cxx::bridge]
@ -13,4 +15,18 @@ pub mod ffi {
}
}
#[cxx::bridge(namespace = "rust")]
pub mod ffi2 {
extern "Rust" {
fn daemon_entry();
fn zygisk_entry();
type MagiskD;
fn get_magiskd() -> &'static MagiskD;
fn get_log_pipe(self: &MagiskD) -> i32;
fn close_log_pipe(self: &MagiskD);
fn setup_logfile(self: &MagiskD);
}
}
fn rust_test_entry() {}

160
native/src/core/logging.cpp
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@ -1,160 +0,0 @@
#include <sys/uio.h>
#include <android/log.h>
#include <magisk.hpp>
#include <base.hpp>
#include <daemon.hpp>
#include <stream.hpp>
#include "core.hpp"
using namespace std;
struct log_meta {
int prio;
int len;
int pid;
int tid;
};
atomic<int> logd_fd = -1;
void setup_logfile(bool reset) {
if (logd_fd < 0)
return;
iovec iov{};
log_meta meta = {
.prio = -1,
.len = reset
};
iov.iov_base = &meta;
iov.iov_len = sizeof(meta);
writev(logd_fd, &iov, 1);
}
// Maximum message length for pipes to transfer atomically
#define MAX_MSG_LEN (int) (PIPE_BUF - sizeof(log_meta))
static void *logfile_writer(void *arg) {
int pipefd = (long) arg;
run_finally close_pipes([=] {
// Close up all logging pipes when thread dies
close(pipefd);
close(logd_fd.exchange(-1));
});
struct {
void *data;
size_t len;
} tmp{};
stream_ptr strm = make_unique<byte_stream>(tmp.data, tmp.len);
bool switched = false;
log_meta meta{};
char buf[MAX_MSG_LEN];
char aux[64];
iovec iov[2];
iov[0].iov_base = aux;
iov[1].iov_base = buf;
for (;;) {
// Read meta data
if (read(pipefd, &meta, sizeof(meta)) != sizeof(meta))
return nullptr;
if (meta.prio < 0) {
if (!switched) {
run_finally free_tmp([&] {
free(tmp.data);
tmp.data = nullptr;
tmp.len = 0;
});
rename(LOGFILE, LOGFILE ".bak");
int fd = open(LOGFILE, O_WRONLY | O_APPEND | O_CREAT | O_CLOEXEC, 0644);
if (fd < 0)
return nullptr;
if (tmp.data)
write(fd, tmp.data, tmp.len);
strm = make_unique<fd_stream>(fd);
switched = true;
}
continue;
}
// Read message
if (read(pipefd, buf, meta.len) != meta.len)
return nullptr;
timeval tv;
tm tm;
gettimeofday(&tv, nullptr);
localtime_r(&tv.tv_sec, &tm);
// Format detailed info
char type;
switch (meta.prio) {
case ANDROID_LOG_DEBUG:
type = 'D';
break;
case ANDROID_LOG_INFO:
type = 'I';
break;
case ANDROID_LOG_WARN:
type = 'W';
break;
default:
type = 'E';
break;
}
long ms = tv.tv_usec / 1000;
size_t off = strftime(aux, sizeof(aux), "%m-%d %T", &tm);
off += ssprintf(aux + off, sizeof(aux) - off,
".%03ld %5d %5d %c : ", ms, meta.pid, meta.tid, type);
iov[0].iov_len = off;
iov[1].iov_len = meta.len;
strm->writev(iov, 2);
}
}
void magisk_log_write(int prio, const char *msg, int len) {
if (logd_fd < 0)
return;
// Truncate
len = std::min(MAX_MSG_LEN, len);
log_meta meta = {
.prio = prio,
.len = len,
.pid = getpid(),
.tid = gettid()
};
iovec iov[2];
iov[0].iov_base = &meta;
iov[0].iov_len = sizeof(meta);
iov[1].iov_base = (void *) msg;
iov[1].iov_len = len;
if (writev(logd_fd, iov, 2) < 0) {
// Stop trying to write to file
close(logd_fd.exchange(-1));
}
}
void start_log_daemon() {
int fds[2];
if (pipe2(fds, O_CLOEXEC) == 0) {
logd_fd = fds[1];
long fd = fds[0];
new_daemon_thread(logfile_writer, (void *) fd);
}
}

300
native/src/core/logging.rs
View File

@ -1,8 +1,27 @@
use base::ffi::LogLevel;
use base::*;
use std::cmp::min;
use std::ffi::{c_char, c_void};
use std::fmt::Arguments;
use std::fs::File;
use std::io::{IoSlice, Read, Write};
use std::os::fd::{AsRawFd, FromRawFd, RawFd};
use std::ptr::null_mut;
use std::{fs, io};
use num_derive::{FromPrimitive, ToPrimitive};
use num_traits::FromPrimitive;
use base::ffi::LogLevel;
use base::libc::{
getpid, gettid, gettimeofday, localtime_r, pipe2, pthread_sigmask, sigaddset, sigset_t,
sigtimedwait, timespec, timeval, tm, O_CLOEXEC, PIPE_BUF, SIGPIPE, SIG_BLOCK, SIG_SETMASK,
};
use base::*;
use crate::daemon::{MagiskD, MAGISKD};
use crate::logging::LogFile::{Actual, Buffer};
#[allow(dead_code, non_camel_case_types)]
#[derive(FromPrimitive, ToPrimitive)]
#[repr(i32)]
enum ALogPriority {
ANDROID_LOG_UNKNOWN = 0,
@ -16,10 +35,14 @@ enum ALogPriority {
ANDROID_LOG_SILENT,
}
type ThreadEntry = extern "C" fn(*mut c_void) -> *mut c_void;
extern "C" {
fn __android_log_write(prio: i32, tag: *const u8, msg: *const u8);
fn magisk_log_write(prio: i32, msg: *const u8, len: i32);
fn zygisk_log_write(prio: i32, msg: *const u8, len: i32);
fn __android_log_write(prio: i32, tag: *const c_char, msg: *const u8);
fn strftime(buf: *mut c_char, len: usize, fmt: *const c_char, tm: *const tm) -> usize;
fn zygisk_fetch_logd() -> RawFd;
fn new_daemon_thread(entry: ThreadEntry, arg: *mut c_void);
}
fn level_to_prio(level: LogLevel) -> i32 {
@ -37,12 +60,12 @@ pub fn android_logging() {
let mut buf: [u8; 4096] = [0; 4096];
fmt_to_buf(&mut buf, args);
unsafe {
__android_log_write(level_to_prio(level), b"Magisk\0".as_ptr(), buf.as_ptr());
__android_log_write(level_to_prio(level), str_ptr!("Magisk"), buf.as_ptr());
}
}
fn android_log_write(level: LogLevel, msg: &[u8]) {
unsafe {
__android_log_write(level_to_prio(level), b"Magisk\0".as_ptr(), msg.as_ptr());
__android_log_write(level_to_prio(level), str_ptr!("Magisk"), msg.as_ptr());
}
}
@ -62,15 +85,15 @@ pub fn magisk_logging() {
let mut buf: [u8; 4096] = [0; 4096];
let len = fmt_to_buf(&mut buf, args);
unsafe {
__android_log_write(level_to_prio(level), b"Magisk\0".as_ptr(), buf.as_ptr());
magisk_log_write(level_to_prio(level), buf.as_ptr(), len as i32);
__android_log_write(level_to_prio(level), str_ptr!("Magisk"), buf.as_ptr());
}
magisk_log_write(level_to_prio(level), &buf[..len]);
}
fn magisk_write(level: LogLevel, msg: &[u8]) {
unsafe {
__android_log_write(level_to_prio(level), b"Magisk\0".as_ptr(), msg.as_ptr());
magisk_log_write(level_to_prio(level), msg.as_ptr(), msg.len() as i32);
__android_log_write(level_to_prio(level), str_ptr!("Magisk"), msg.as_ptr());
}
magisk_log_write(level_to_prio(level), &msg);
}
let logger = Logger {
@ -89,15 +112,15 @@ pub fn zygisk_logging() {
let mut buf: [u8; 4096] = [0; 4096];
let len = fmt_to_buf(&mut buf, args);
unsafe {
__android_log_write(level_to_prio(level), b"Magisk\0".as_ptr(), buf.as_ptr());
zygisk_log_write(level_to_prio(level), buf.as_ptr(), len as i32);
__android_log_write(level_to_prio(level), str_ptr!("Magisk"), buf.as_ptr());
}
zygisk_log_write(level_to_prio(level), &buf[..len]);
}
fn zygisk_write(level: LogLevel, msg: &[u8]) {
unsafe {
__android_log_write(level_to_prio(level), b"Magisk\0".as_ptr(), msg.as_ptr());
zygisk_log_write(level_to_prio(level), msg.as_ptr(), msg.len() as i32);
__android_log_write(level_to_prio(level), str_ptr!("Magisk"), msg.as_ptr());
}
zygisk_log_write(level_to_prio(level), &msg);
}
let logger = Logger {
@ -110,3 +133,250 @@ pub fn zygisk_logging() {
LOGGER = logger;
}
}
#[derive(Default)]
#[repr(C)]
struct LogMeta {
prio: i32,
len: i32,
pid: i32,
tid: i32,
}
const MAX_MSG_LEN: usize = PIPE_BUF - std::mem::size_of::<LogMeta>();
fn do_magisk_log_write(logd: &mut File, prio: i32, msg: &[u8]) -> io::Result<usize> {
// Truncate message if needed
let len = min(MAX_MSG_LEN, msg.len());
let msg = &msg[..len];
let meta = LogMeta {
prio,
len: len as i32,
pid: unsafe { getpid() },
tid: unsafe { gettid() },
};
let io1 = IoSlice::new(meta.as_raw_bytes());
let io2 = IoSlice::new(msg);
logd.write_vectored(&[io1, io2])
}
fn magisk_log_write(prio: i32, msg: &[u8]) {
let magiskd = match MAGISKD.get() {
None => return,
Some(s) => s,
};
let logd_cell = magiskd.logd.lock().unwrap();
let mut logd_ref = logd_cell.borrow_mut();
let logd = match logd_ref.as_mut() {
None => return,
Some(s) => s,
};
let result = do_magisk_log_write(logd, prio, &msg);
// If any error occurs, shut down the logd pipe
if result.is_err() {
*logd_ref = None;
}
}
fn zygisk_log_write(prio: i32, msg: &[u8]) {
let magiskd = match MAGISKD.get() {
None => return,
Some(s) => s,
};
let logd_cell = magiskd.logd.lock().unwrap();
let mut logd_ref = logd_cell.borrow_mut();
if logd_ref.is_none() {
android_logging();
unsafe {
let fd = zygisk_fetch_logd();
if fd < 0 {
return;
}
*logd_ref = Some(File::from_raw_fd(fd));
}
// Only re-enable zygisk logging if success
zygisk_logging();
};
let logd = logd_ref.as_mut().unwrap();
// Block SIGPIPE
let mut mask: sigset_t;
let mut orig_mask: sigset_t;
unsafe {
mask = std::mem::zeroed();
orig_mask = std::mem::zeroed();
sigaddset(&mut mask, SIGPIPE);
pthread_sigmask(SIG_BLOCK, &mask, &mut orig_mask);
}
let result = do_magisk_log_write(logd, prio, &msg);
// Consume SIGPIPE if exists, then restore mask
unsafe {
let mut ts: timespec = std::mem::zeroed();
sigtimedwait(&mask, null_mut(), &ts);
pthread_sigmask(SIG_SETMASK, &orig_mask, null_mut());
}
// If any error occurs, shut down the logd pipe
if result.is_err() {
*logd_ref = None;
}
}
// The following is implementation for the logging daemon
enum LogFile<'a> {
Buffer(&'a mut Vec<u8>),
Actual(File),
}
impl LogFile<'_> {
fn as_write(&mut self) -> &mut dyn Write {
match self {
Buffer(e) => e,
Actual(ref mut e) => e,
}
}
}
impl FlatData for LogMeta {}
extern "C" fn logfile_writer(arg: *mut c_void) -> *mut c_void {
fn writer_loop(pipefd: RawFd) -> io::Result<()> {
let mut pipe = unsafe { File::from_raw_fd(pipefd) };
let mut tmp = Vec::new();
let mut logfile: LogFile = Buffer(&mut tmp);
let mut meta = LogMeta::default();
let mut buf: [u8; MAX_MSG_LEN] = [0; MAX_MSG_LEN];
let mut aux: [u8; 64] = [0; 64];
loop {
// Read request
pipe.read_exact(meta.as_raw_bytes_mut())?;
if meta.prio < 0 {
if matches!(logfile, LogFile::Buffer(_)) {
fs::rename(LOGFILE!(), concat!(LOGFILE!(), ".bak")).ok();
let mut out = File::create(LOGFILE!())?;
out.write_all(tmp.as_slice())?;
tmp = Vec::new();
logfile = Actual(out);
}
continue;
}
if meta.len < 0 || meta.len > buf.len() as i32 {
continue;
}
// Read the rest of the message
let msg = &mut buf[..(meta.len as usize)];
pipe.read_exact(msg)?;
// Start building the log string
let prio =
ALogPriority::from_i32(meta.prio).unwrap_or(ALogPriority::ANDROID_LOG_UNKNOWN);
let prio = match prio {
ALogPriority::ANDROID_LOG_VERBOSE => 'V',
ALogPriority::ANDROID_LOG_DEBUG => 'D',
ALogPriority::ANDROID_LOG_INFO => 'I',
ALogPriority::ANDROID_LOG_WARN => 'W',
ALogPriority::ANDROID_LOG_ERROR => 'E',
// Unsupported values, skip
_ => continue,
};
// Note: the obvious better implementation is to use the rust chrono crate, however
// the crate cannot fetch the proper local timezone without pulling in a bunch of
// timezone handling code. To reduce final binary size, fallback to use libc.
let mut aux_len: usize;
unsafe {
let mut tv: timeval = std::mem::zeroed();
let mut tm: tm = std::mem::zeroed();
gettimeofday(&mut tv, null_mut());
localtime_r(&tv.tv_sec, &mut tm);
aux_len = strftime(
aux.as_mut_ptr().cast(),
aux.len(),
str_ptr!("%m-%d %T"),
&tm,
) as usize;
let ms = tv.tv_usec / 1000;
aux_len += bfmt!(
&mut aux[aux_len..],
".{:03} {:5} {:5} {} : ",
ms,
meta.pid,
meta.tid,
prio
);
}
let io1 = IoSlice::new(&aux[..aux_len]);
let io2 = IoSlice::new(msg);
logfile.as_write().write_vectored(&[io1, io2])?;
}
}
writer_loop(arg as RawFd).ok();
// If any error occurs, shut down the logd pipe
if let Some(magiskd) = MAGISKD.get() {
magiskd.close_log_pipe();
}
null_mut()
}
impl MagiskD {
pub fn start_log_daemon(&self) {
let mut fds: [i32; 2] = [0; 2];
unsafe {
if pipe2(fds.as_mut_ptr(), O_CLOEXEC) == 0 {
let logd = self.logd.lock().unwrap();
*logd.borrow_mut() = Some(File::from_raw_fd(fds[1]));
new_daemon_thread(logfile_writer, fds[0] as *mut c_void);
}
}
}
pub fn get_log_pipe(&self) -> RawFd {
let logd_cell = self.logd.lock().unwrap();
let logd_ref = logd_cell.borrow();
let logd = logd_ref.as_ref();
match logd {
None => -1,
Some(s) => s.as_raw_fd(),
}
}
pub fn close_log_pipe(&self) {
let guard = self.logd.lock().unwrap();
*guard.borrow_mut() = None;
}
pub fn setup_logfile(&self) {
let logd_cell = self.logd.lock().unwrap();
let mut logd_ref = logd_cell.borrow_mut();
let logd = match logd_ref.as_mut() {
None => return,
Some(s) => s,
};
let meta = LogMeta {
prio: -1,
len: 0,
pid: 0,
tid: 0,
};
logd.write_all(meta.as_raw_bytes()).ok();
}
}

4
native/src/include/daemon.hpp
View File

@ -83,10 +83,6 @@ void clear_poll();
// Thread pool
void exec_task(std::function<void()> &&task);
// Logging
extern std::atomic<int> logd_fd;
extern "C" void magisk_log_write(int prio, const char *msg, int len);
// Daemon handlers
void boot_stage_handler(int client, int code);
void denylist_handler(int client, const sock_cred *cred);

43
native/src/zygisk/entry.cpp
View File

@ -41,7 +41,7 @@ extern "C" void unload_first_stage() {
}
extern "C" void zygisk_inject_entry(void *handle) {
zygisk_logging();
rust::zygisk_entry();
ZLOGD("load success\n");
char *ld = getenv("LD_PRELOAD");
@ -62,7 +62,7 @@ extern "C" void zygisk_inject_entry(void *handle) {
// The following code runs in zygote/app process
extern "C" void zygisk_log_write(int prio, const char *msg, int len) {
extern "C" int zygisk_fetch_logd() {
// If we don't have the log pipe set, request magiskd for it. This could actually happen
// multiple times in the zygote daemon (parent process) because we had to close this
// file descriptor to prevent crashing.
@ -77,37 +77,18 @@ extern "C" void zygisk_log_write(int prio, const char *msg, int len) {
// add this FD into fds_to_ignore to pass the check. For other cases, we accomplish this by
// hooking __android_log_close and closing it at the same time as the rest of logging FDs.
if (logd_fd < 0) {
android_logging();
if (int fd = zygisk_request(ZygiskRequest::GET_LOG_PIPE); fd >= 0) {
int log_pipe = -1;
if (read_int(fd) == 0) {
log_pipe = recv_fd(fd);
}
close(fd);
if (log_pipe >= 0) {
// Only re-enable zygisk logging if possible
logd_fd = log_pipe;
zygisk_logging();
}
} else {
return;
if (int fd = zygisk_request(ZygiskRequest::GET_LOG_PIPE); fd >= 0) {
int log_pipe = -1;
if (read_int(fd) == 0) {
log_pipe = recv_fd(fd);
}
close(fd);
if (log_pipe >= 0) {
return log_pipe;
}
}
// Block SIGPIPE
sigset_t mask;
sigset_t orig_mask;
sigemptyset(&mask);
sigaddset(&mask, SIGPIPE);
pthread_sigmask(SIG_BLOCK, &mask, &orig_mask);
magisk_log_write(prio, msg, len);
// Consume SIGPIPE if exists, then restore mask
timespec ts{};
sigtimedwait(&mask, nullptr, &ts);
pthread_sigmask(SIG_SETMASK, &orig_mask, nullptr);
return -1;
}
static inline bool should_load_modules(uint32_t flags) {
@ -340,7 +321,7 @@ static void get_process_info(int client, const sock_cred *cred) {
}
static void send_log_pipe(int fd) {
// There is race condition here, but we can't really do much about it...
int logd_fd = rust::get_magiskd().get_log_pipe();
if (logd_fd >= 0) {
write_int(fd, 0);
send_fd(fd, logd_fd);

19
native/src/zygisk/hook.cpp
View File

@ -20,6 +20,8 @@ using namespace std;
using jni_hook::hash_map;
using jni_hook::tree_map;
using xstring = jni_hook::string;
using rust::MagiskD;
using rust::get_magiskd;
// Extreme verbose logging
//#define ZLOGV(...) ZLOGD(__VA_ARGS__)
@ -67,6 +69,7 @@ struct HookContext {
AppSpecializeArgs_v3 *app;
ServerSpecializeArgs_v1 *server;
} args;
const MagiskD &magiskd;
const char *process;
list<ZygiskModule> modules;
@ -94,7 +97,7 @@ struct HookContext {
vector<IgnoreInfo> ignore_info;
HookContext(JNIEnv *env, void *args) :
env(env), args{args}, process(nullptr), pid(-1), info_flags(0),
env(env), args{args}, magiskd(get_magiskd()), process(nullptr), pid(-1), info_flags(0),
hook_info_lock(PTHREAD_MUTEX_INITIALIZER) {
static bool restored_env = false;
if (!restored_env) {
@ -171,9 +174,9 @@ DCL_HOOK_FUNC(int, unshare, int flags) {
DCL_HOOK_FUNC(void, android_log_close) {
if (g_ctx == nullptr) {
// Happens during un-managed fork like nativeForkApp, nativeForkUsap
close(logd_fd.exchange(-1));
get_magiskd().close_log_pipe();
} else if (!g_ctx->flags[SKIP_FD_SANITIZATION]) {
close(logd_fd.exchange(-1));
g_ctx->magiskd.close_log_pipe();
if (g_ctx->is_child()) {
// Switch to plain old android logging because we cannot talk
// to magiskd to fetch our log pipe afterwards anyways.
@ -484,6 +487,7 @@ void HookContext::sanitize_fds() {
int dfd = dirfd(dir.get());
for (dirent *entry; (entry = xreaddir(dir.get()));) {
int fd = parse_int(entry->d_name);
int logd_fd = magiskd.get_log_pipe();
if ((fd < 0 || fd >= MAX_FD_SIZE || !allowed_fds[fd]) && fd != dfd && fd != logd_fd) {
close(fd);
}
@ -570,7 +574,7 @@ void HookContext::app_specialize_post() {
// Cleanups
env->ReleaseStringUTFChars(args.app->nice_name, process);
close(logd_fd.exchange(-1));
magiskd.close_log_pipe();
android_logging();
}
@ -690,8 +694,11 @@ void HookContext::nativeForkAndSpecialize_pre() {
// if fds_to_ignore does not exist and there's no FileDescriptorTable::Create,
// we can skip fd sanitization
flags[SKIP_FD_SANITIZATION] = !dlsym(RTLD_DEFAULT, "_ZN19FileDescriptorTable6CreateEv");
} else if (logd_fd >= 0) {
exempted_fds.push_back(logd_fd);
} else {
int logd_fd = magiskd.get_log_pipe();
if (logd_fd >= 0) {
exempted_fds.push_back(logd_fd);
}
}
fork_pre();