Cleaner daemon handlers

This commit is contained in:
topjohnwu 2021-08-11 22:57:08 -07:00
parent 3ea10b7cf9
commit 20860da4b4
2 changed files with 55 additions and 41 deletions

View File

@ -39,15 +39,16 @@ static bool verify_client(pid_t pid) {
static bool check_zygote(pid_t pid) {
char buf[32];
sprintf(buf, "/proc/%d/attr/current", pid);
auto fp = open_file(buf, "r");
if (!fp)
if (auto fp = open_file(buf, "r")) {
fscanf(fp.get(), "%s", buf);
return buf == "u:r:zygote:s0"sv;
} else {
return false;
fscanf(fp.get(), "%s", buf);
return buf == "u:r:zygote:s0"sv;
}
}
static void request_handler(int client, int req_code, ucred cred) {
switch (req_code) {
static void handle_request_async(int client, int code, ucred cred) {
switch (code) {
case MAGISKHIDE:
magiskhide_handler(client, &cred);
break;
@ -78,26 +79,43 @@ static void request_handler(int client, int req_code, ucred cred) {
}
}
static void handle_request_sync(int client, int code) {
switch (code) {
case CHECK_VERSION:
write_string(client, MAGISK_VERSION ":MAGISK");
break;
case CHECK_VERSION_CODE:
write_int(client, MAGISK_VER_CODE);
break;
case GET_PATH:
write_string(client, MAGISKTMP.data());
break;
case START_DAEMON:
setup_logfile(true);
break;
}
}
static void handle_request(int client) {
int req_code;
int code;
// Verify client credentials
ucred cred;
get_client_cred(client, &cred);
bool is_root = cred.uid == 0;
bool is_zygote = check_zygote(cred.pid);
bool is_client = verify_client(cred.pid);
bool is_zygote = !is_client && check_zygote(cred.pid);
if (!is_root && !is_zygote && !is_client)
goto shortcut;
goto done;
req_code = read_int(client);
if (req_code < 0 || req_code >= DAEMON_CODE_END)
goto shortcut;
code = read_int(client);
if (code < 0 || (code & DAEMON_CODE_MASK) >= DAEMON_CODE_END)
goto done;
// Check client permissions
switch (req_code) {
switch (code) {
case POST_FS_DATA:
case LATE_START:
case BOOT_COMPLETE:
@ -105,44 +123,33 @@ static void handle_request(int client) {
case GET_PATH:
if (!is_root) {
write_int(client, ROOT_REQUIRED);
goto shortcut;
goto done;
}
break;
case REMOVE_MODULES:
if (cred.uid != UID_SHELL && cred.uid != UID_ROOT) {
if (!is_root && cred.uid != UID_SHELL) {
write_int(client, 1);
goto shortcut;
goto done;
}
break;
case MAGISKHIDE: // accept hide request from zygote
if (!is_root && !is_zygote) {
write_int(client, ROOT_REQUIRED);
goto shortcut;
goto done;
}
break;
}
// Simple requests
switch (req_code) {
case CHECK_VERSION:
write_string(client, MAGISK_VERSION ":MAGISK");
goto shortcut;
case CHECK_VERSION_CODE:
write_int(client, MAGISK_VER_CODE);
goto shortcut;
case GET_PATH:
write_string(client, MAGISKTMP.data());
goto shortcut;
case START_DAEMON:
setup_logfile(true);
goto shortcut;
if (code & SYNC_FLAG) {
handle_request_sync(client, code);
goto done;
}
// Create new thread to handle complex requests
new_daemon_thread([=] { return request_handler(client, req_code, cred); });
new_daemon_thread([=] { handle_request_async(client, code, cred); });
return;
shortcut:
done:
close(client);
}

View File

@ -2,27 +2,34 @@
#include <pthread.h>
#include <string>
#include <limits>
#include <socket.hpp>
// Daemon command code flags/masks
enum : int {
SYNC_FLAG = (1 << 30),
DAEMON_CODE_MASK = std::numeric_limits<int>::max() >> 1
};
// Daemon command codes
enum {
START_DAEMON,
SUPERUSER,
CHECK_VERSION,
CHECK_VERSION_CODE,
enum : int {
START_DAEMON = SYNC_FLAG | 0,
CHECK_VERSION = SYNC_FLAG | 1,
CHECK_VERSION_CODE = SYNC_FLAG | 2,
GET_PATH = SYNC_FLAG | 3,
SUPERUSER = 4,
POST_FS_DATA,
LATE_START,
BOOT_COMPLETE,
MAGISKHIDE,
SQLITE_CMD,
REMOVE_MODULES,
GET_PATH,
DAEMON_CODE_END,
};
// Return codes for daemon
enum {
enum : int {
DAEMON_ERROR = -1,
DAEMON_SUCCESS = 0,
ROOT_REQUIRED,
@ -30,7 +37,7 @@ enum {
};
// Daemon state
enum {
enum : int {
STATE_NONE,
STATE_POST_FS_DATA,
STATE_POST_FS_DATA_DONE,