Magisk/native/jni/init/getinfo.cpp
2019-06-15 22:25:09 -07:00

153 lines
3.7 KiB
C++

#include <sys/sysmacros.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <linux/input.h>
#include <fcntl.h>
#include <utils.h>
#include <logging.h>
#include "init.h"
using namespace std;
#define DEFAULT_DT_DIR "/proc/device-tree/firmware/android"
static void parse_cmdline(const std::function<void (std::string_view, const char *)> &fn) {
char cmdline[4096];
int fd = open("/proc/cmdline", O_RDONLY | O_CLOEXEC);
cmdline[read(fd, cmdline, sizeof(cmdline))] = '\0';
close(fd);
char *tok, *eql, *tmp, *saveptr;
saveptr = cmdline;
while ((tok = strtok_r(nullptr, " \n", &saveptr)) != nullptr) {
eql = strchr(tok, '=');
if (eql) {
*eql = '\0';
if (eql[1] == '"') {
tmp = strchr(saveptr, '"');
if (tmp != nullptr) {
*tmp = '\0';
saveptr[-1] = ' ';
saveptr = tmp + 1;
eql++;
}
}
fn(tok, eql + 1);
} else {
fn(tok, "");
}
}
}
#define test_bit(bit, array) (array[bit / 8] & (1 << (bit % 8)))
static bool check_key_combo() {
uint8_t bitmask[(KEY_MAX + 1) / 8];
vector<int> events;
constexpr const char *name = "/event";
for (int minor = 64; minor < 96; ++minor) {
if (mknod(name, S_IFCHR | 0444, makedev(13, minor))) {
PLOGE("mknod");
continue;
}
int fd = open(name, O_RDONLY | O_CLOEXEC);
unlink(name);
if (fd < 0)
continue;
memset(bitmask, 0, sizeof(bitmask));
ioctl(fd, EVIOCGBIT(EV_KEY, sizeof(bitmask)), bitmask);
if (test_bit(KEY_VOLUMEUP, bitmask))
events.push_back(fd);
}
if (events.empty())
return false;
RunFinally fin([&]() -> void {
for (const int &fd : events)
close(fd);
});
// Return true if volume key up is hold for more than 3 seconds
int count = 0;
for (int i = 0; i < 500; ++i) {
for (const int &fd : events) {
memset(bitmask, 0, sizeof(bitmask));
ioctl(fd, EVIOCGKEY(sizeof(bitmask)), bitmask);
if (test_bit(KEY_VOLUMEUP, bitmask)) {
count++;
break;
}
}
if (count >= 300) {
LOGD("KEY_VOLUMEUP detected: disable system-as-root\n");
return true;
}
// Check every 10ms
usleep(10000);
}
return false;
}
void load_kernel_info(cmdline *cmd) {
// Communicate with kernel using procfs and sysfs
xmkdir("/proc", 0755);
xmount("proc", "/proc", "proc", 0, nullptr);
xmkdir("/sys", 0755);
xmount("sysfs", "/sys", "sysfs", 0, nullptr);
bool enter_recovery = false;
bool kirin = false;
bool recovery_mode = false;
parse_cmdline([&](auto key, auto value) -> void {
LOGD("cmdline: [%s]=[%s]\n", key.data(), value);
if (key == "androidboot.slot_suffix") {
strcpy(cmd->slot, value);
} else if (key == "androidboot.slot") {
cmd->slot[0] = '_';
strcpy(cmd->slot + 1, value);
} else if (key == "skip_initramfs") {
cmd->system_as_root = true;
} else if (key == "androidboot.android_dt_dir") {
strcpy(cmd->dt_dir, value);
} else if (key == "enter_recovery") {
enter_recovery = value[0] == '1';
} else if (key == "androidboot.hardware") {
kirin = strstr(value, "kirin") || strstr(value, "hi3660") || strstr(value, "hi6250");
}
});
parse_prop_file("/.backup/.magisk", [&](auto key, auto value) -> bool {
if (key == "RECOVERYMODE" && value == "true")
recovery_mode = true;
return true;
});
if (kirin && enter_recovery) {
// Inform that we are actually booting as recovery
if (!recovery_mode) {
if (FILE *f = fopen("/.backup/.magisk", "ae"); f) {
fprintf(f, "RECOVERYMODE=true\n");
fclose(f);
}
recovery_mode = true;
}
}
if (recovery_mode) {
LOGD("Running in recovery mode, waiting for key...\n");
cmd->system_as_root = !check_key_combo();
}
if (cmd->dt_dir[0] == '\0')
strcpy(cmd->dt_dir, DEFAULT_DT_DIR);
LOGD("system_as_root=[%d]\n", cmd->system_as_root);
LOGD("slot=[%s]\n", cmd->slot);
LOGD("dt_dir=[%s]\n", cmd->dt_dir);
}