Magisk/jni/utils/misc.c

422 lines
8.8 KiB
C

/* misc.c - Store all functions that are unable to be catagorized clearly
*/
#define _GNU_SOURCE
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <dirent.h>
#include <unistd.h>
#include <fcntl.h>
#include <pwd.h>
#include <signal.h>
#include <errno.h>
#include <sched.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <selinux/selinux.h>
#include "logging.h"
#include "utils.h"
int quit_signals[] = { SIGALRM, SIGABRT, SIGHUP, SIGPIPE, SIGQUIT, SIGTERM, SIGINT, 0 };
unsigned get_shell_uid() {
struct passwd* ppwd = getpwnam("shell");
if (NULL == ppwd)
return 2000;
return ppwd->pw_uid;
}
unsigned get_system_uid() {
struct passwd* ppwd = getpwnam("system");
if (NULL == ppwd)
return 1000;
return ppwd->pw_uid;
}
unsigned get_radio_uid() {
struct passwd* ppwd = getpwnam("radio");
if (NULL == ppwd)
return 1001;
return ppwd->pw_uid;
}
int check_data() {
int ret = 0;
char buffer[4096];
FILE *fp = xfopen("/proc/mounts", "r");
while (fgets(buffer, sizeof(buffer), fp)) {
if (strstr(buffer, " /data ")) {
if (strstr(buffer, "tmpfs") == NULL)
ret = 1;
break;
}
}
fclose(fp);
return ret;
}
/* All the string should be freed manually!! */
int file_to_vector(const char* filename, struct vector *v) {
char *line = NULL;
size_t len = 0;
ssize_t read;
FILE *fp = xfopen(filename, "r");
if (fp == NULL)
return 1;
while ((read = getline(&line, &len, fp)) != -1) {
// Remove end newline
if (line[read - 1] == '\n')
line[read - 1] = '\0';
vec_push_back(v, line);
line = NULL;
}
fclose(fp);
return 0;
}
int vector_to_file(const char *filename, struct vector *v) {
FILE *fp = xfopen(filename, "w");
if (fp == NULL)
return 1;
char *line;
vec_for_each(v, line) {
fprintf(fp, "%s\n", line);
}
fclose(fp);
return 0;
}
/* Check if the string only contains digits */
static int is_num(const char *s) {
int len = strlen(s);
for (int i = 0; i < len; ++i)
if (s[i] < '0' || s[i] > '9')
return 0;
return 1;
}
/* Read a whole line from file descriptor */
ssize_t fdgets(char *buf, const size_t size, int fd) {
ssize_t len = 0;
buf[0] = '\0';
while (read(fd, buf + len, 1) >= 0 && len < size - 1) {
if (buf[len] == '\0' || buf[len++] == '\n') {
buf[len] = '\0';
break;
}
}
buf[size - 1] = '\0';
return len;
}
/* Call func for each process */
void ps(void (*func)(int)) {
DIR *dir;
struct dirent *entry;
if (!(dir = xopendir("/proc")))
return;
while ((entry = xreaddir(dir))) {
if (entry->d_type == DT_DIR) {
if (is_num(entry->d_name))
func(atoi(entry->d_name));
}
}
closedir(dir);
}
// Internal usage
static void (*ps_filter_cb)(int);
static const char *ps_filter_pattern;
static void proc_name_filter(int pid) {
char buf[64];
int fd;
snprintf(buf, sizeof(buf), "/proc/%d/cmdline", pid);
if ((fd = open(buf, O_RDONLY)) == -1)
return;
if (fdgets(buf, sizeof(buf), fd) == 0) {
snprintf(buf, sizeof(buf), "/proc/%d/comm", pid);
close(fd);
if ((fd = open(buf, O_RDONLY)) == -1)
return;
fdgets(buf, sizeof(buf), fd);
}
if (strcmp(buf, ps_filter_pattern) == 0) {
ps_filter_cb(pid);
}
close(fd);
}
/* Call func with process name filtered with pattern */
void ps_filter_proc_name(const char *pattern, void (*func)(int)) {
ps_filter_cb = func;
ps_filter_pattern = ((pattern == NULL) ? "" : pattern);
ps(proc_name_filter);
}
void unlock_blocks() {
DIR *dir;
struct dirent *entry;
int fd, dev, OFF = 0;
if ((dev = xopen("/dev/block", O_RDONLY | O_CLOEXEC)) < 0)
return;
dir = fdopendir(dev);
while((entry = readdir(dir))) {
if (entry->d_type == DT_BLK) {
if ((fd = openat(dev, entry->d_name, O_RDONLY)) < 0)
continue;
if (ioctl(fd, BLKROSET, &OFF) == -1)
PLOGE("unlock %s", entry->d_name);
close(fd);
}
}
close(dev);
}
void setup_sighandlers(void (*handler)(int)) {
struct sigaction act;
memset(&act, 0, sizeof(act));
act.sa_handler = handler;
for (int i = 0; quit_signals[i]; ++i) {
sigaction(quit_signals[i], &act, NULL);
}
}
/*
fd == NULL -> Ignore output
*fd < 0 -> Open pipe and set *fd to the read end
*fd >= 0 -> STDOUT (or STDERR) will be redirected to *fd
*cb -> A callback function which runs after fork
*/
static int v_exec_command(int err, int *fd, void (*setupenv)(struct vector*), const char *argv0, va_list argv) {
int pipefd[2], writeEnd = -1;
if (fd) {
if (*fd < 0) {
if (xpipe2(pipefd, O_CLOEXEC) == -1)
return -1;
writeEnd = pipefd[1];
} else {
writeEnd = *fd;
}
}
// Collect va_list into vector
struct vector args;
vec_init(&args);
vec_push_back(&args, strdup(argv0));
for (void *arg = va_arg(argv, void*); arg; arg = va_arg(argv, void*))
vec_push_back(&args, strdup(arg));
vec_push_back(&args, NULL);
// Setup environment
char *const *envp;
struct vector env;
vec_init(&env);
if (setupenv) {
setupenv(&env);
envp = (char **) vec_entry(&env);
} else {
extern char **environ;
envp = environ;
}
int pid = fork();
if (pid != 0) {
if (fd && *fd < 0) {
// Give the read end and close write end
*fd = pipefd[0];
close(pipefd[1]);
}
vec_deep_destroy(&args);
vec_deep_destroy(&env);
return pid;
}
// Don't return to the daemon if anything goes wrong
err_handler = exit_proc;
if (fd) {
xdup2(writeEnd, STDOUT_FILENO);
if (err) xdup2(writeEnd, STDERR_FILENO);
}
execvpe(argv0, (char **) vec_entry(&args), envp);
PLOGE("execvpe");
return -1;
}
int exec_command_sync(char *const argv0, ...) {
va_list argv;
va_start(argv, argv0);
int pid, status;
pid = v_exec_command(0, NULL, NULL, argv0, argv);
va_end(argv);
if (pid < 0)
return pid;
waitpid(pid, &status, 0);
return WEXITSTATUS(status);
}
int exec_command(int err, int *fd, void (*setupenv)(struct vector*), const char *argv0, ...) {
va_list argv;
va_start(argv, argv0);
int pid = v_exec_command(err, fd, setupenv, argv0, argv);
va_end(argv);
return pid;
}
int mkdir_p(const char *pathname, mode_t mode) {
char *path = strdup(pathname), *p;
errno = 0;
for (p = path + 1; *p; ++p) {
if (*p == '/') {
*p = '\0';
if (mkdir(path, mode) == -1) {
if (errno != EEXIST)
return -1;
}
*p = '/';
}
}
if (mkdir(path, mode) == -1) {
if (errno != EEXIST)
return -1;
}
free(path);
return 0;
}
int bind_mount(const char *from, const char *to) {
int ret = xmount(from, to, NULL, MS_BIND, NULL);
#ifdef MAGISK_DEBUG
LOGI("bind_mount: %s -> %s\n", from, to);
#else
LOGI("bind_mount: %s\n", to);
#endif
return ret;
}
int open_new(const char *filename) {
return xopen(filename, O_WRONLY | O_CREAT | O_TRUNC, 0644);
}
int cp_afc(const char *source, const char *target) {
struct stat buf;
xlstat(source, &buf);
if (S_ISDIR(buf.st_mode)) {
DIR *dir;
struct dirent *entry;
char *s_path, *t_path;
if (!(dir = xopendir(source)))
return 1;
s_path = xmalloc(PATH_MAX);
t_path = xmalloc(PATH_MAX);
mkdir_p(target, 0755);
clone_attr(source, target);
while ((entry = xreaddir(dir))) {
if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0)
continue;
snprintf(s_path, PATH_MAX, "%s/%s", source, entry->d_name);
snprintf(t_path, PATH_MAX, "%s/%s", target, entry->d_name);
cp_afc(s_path, t_path);
}
free(s_path);
free(t_path);
closedir(dir);
} else{
unlink(target);
if (S_ISREG(buf.st_mode)) {
int sfd, tfd;
sfd = xopen(source, O_RDONLY);
tfd = xopen(target, O_WRONLY | O_CREAT | O_TRUNC);
xsendfile(tfd, sfd, NULL, buf.st_size);
fclone_attr(sfd, tfd);
close(sfd);
close(tfd);
} else if (S_ISLNK(buf.st_mode)) {
char buffer[PATH_MAX];
xreadlink(source, buffer, sizeof(buffer));
xsymlink(buffer, target);
clone_attr(source, target);
} else {
return 1;
}
}
return 0;
}
void clone_attr(const char *source, const char *target) {
struct stat buf;
lstat(target, &buf);
chmod(target, buf.st_mode & 0777);
chown(target, buf.st_uid, buf.st_gid);
char *con;
lgetfilecon(source, &con);
lsetfilecon(target, con);
free(con);
}
void fclone_attr(const int sourcefd, const int targetfd) {
struct stat buf;
fstat(sourcefd, &buf);
fchmod(targetfd, buf.st_mode & 0777);
fchown(targetfd, buf.st_uid, buf.st_gid);
char *con;
fgetfilecon(sourcefd, &con);
fsetfilecon(targetfd, con);
free(con);
}
void get_client_cred(int fd, struct ucred *cred) {
socklen_t ucred_length = sizeof(*cred);
if(getsockopt(fd, SOL_SOCKET, SO_PEERCRED, cred, &ucred_length))
PLOGE("getsockopt");
}
int switch_mnt_ns(int pid) {
char mnt[32];
snprintf(mnt, sizeof(mnt), "/proc/%d/ns/mnt", pid);
if(access(mnt, R_OK) == -1) return 1; // Maybe process died..
int fd, ret;
fd = xopen(mnt, O_RDONLY);
if (fd < 0) return 1;
// Switch to its namespace
ret = setns(fd, 0);
close(fd);
return ret;
}
int fork_dont_care() {
int pid = fork();
if (pid) {
waitpid(pid, NULL, 0);
return pid;
} else if ((pid = fork())) {
exit(0);
}
return 0;
}