mirror of
https://github.com/topjohnwu/Magisk.git
synced 2024-12-25 11:07:38 +00:00
f0533fca70
The previous implementation is great if multiple different requesters call su rapidly in a very short period of time, however in the real world this is nearly impossible to happen. This comes with quite a big overhead, since it requires two lists and also an everlasting background thread to constantly maintain the lists. The new implementation will spawn a collector thread for each cache miss, and the thread will terminate itself once the data is invalidated.
109 lines
3.0 KiB
C
109 lines
3.0 KiB
C
/* su_socket.c - Functions for communication to client
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
#include <errno.h>
|
|
#include <endian.h>
|
|
#include <sys/types.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/un.h>
|
|
#include <selinux/selinux.h>
|
|
|
|
#include "magisk.h"
|
|
#include "utils.h"
|
|
#include "su.h"
|
|
#include "magiskpolicy.h"
|
|
|
|
int socket_create_temp(char *path, size_t len) {
|
|
int fd;
|
|
struct sockaddr_un sun;
|
|
|
|
fd = xsocket(AF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0);
|
|
if (fcntl(fd, F_SETFD, FD_CLOEXEC)) {
|
|
PLOGE("fcntl FD_CLOEXEC");
|
|
}
|
|
|
|
memset(&sun, 0, sizeof(sun));
|
|
sun.sun_family = AF_LOCAL;
|
|
snprintf(path, len, "/dev/.socket%d", getpid());
|
|
strcpy(sun.sun_path, path);
|
|
|
|
/*
|
|
* Delete the socket to protect from situations when
|
|
* something bad occured previously and the kernel reused pid from that process.
|
|
* Small probability, isn't it.
|
|
*/
|
|
unlink(path);
|
|
|
|
xbind(fd, (struct sockaddr*) &sun, sizeof(sun));
|
|
xlisten(fd, 1);
|
|
|
|
// Set attributes so requester can access it
|
|
setfilecon(path, "u:object_r:"SEPOL_FILE_DOMAIN":s0");
|
|
chown(path, su_ctx->info->manager_stat.st_uid, su_ctx->info->manager_stat.st_gid);
|
|
|
|
return fd;
|
|
}
|
|
|
|
int socket_accept(int serv_fd) {
|
|
struct timeval tv;
|
|
fd_set fds;
|
|
int rc;
|
|
|
|
/* Wait 60 seconds for a connection, then give up. */
|
|
tv.tv_sec = 60;
|
|
tv.tv_usec = 0;
|
|
FD_ZERO(&fds);
|
|
FD_SET(serv_fd, &fds);
|
|
do {
|
|
rc = select(serv_fd + 1, &fds, NULL, NULL, &tv);
|
|
} while (rc < 0 && errno == EINTR);
|
|
if (rc < 1) {
|
|
PLOGE("select");
|
|
}
|
|
|
|
return xaccept4(serv_fd, NULL, NULL, SOCK_CLOEXEC);
|
|
}
|
|
|
|
#define write_data(fd, data, data_len) \
|
|
do { \
|
|
uint32_t __len = htonl(data_len); \
|
|
__len = write((fd), &__len, sizeof(__len)); \
|
|
if (__len != sizeof(__len)) { \
|
|
PLOGE("write(" #data ")"); \
|
|
} \
|
|
__len = write((fd), data, data_len); \
|
|
if (__len != data_len) { \
|
|
PLOGE("write(" #data ")"); \
|
|
} \
|
|
} while (0)
|
|
|
|
#define write_string_data(fd, name, data) \
|
|
do { \
|
|
write_data(fd, name, strlen(name)); \
|
|
write_data(fd, data, strlen(data)); \
|
|
} while (0)
|
|
|
|
// stringify everything.
|
|
#define write_token(fd, name, data) \
|
|
do { \
|
|
char buf[16]; \
|
|
snprintf(buf, sizeof(buf), "%d", data); \
|
|
write_string_data(fd, name, buf); \
|
|
} while (0)
|
|
|
|
void socket_send_request(int fd, const struct su_context *ctx) {
|
|
write_token(fd, "uid", ctx->info->uid);
|
|
write_token(fd, "eof", 1);
|
|
}
|
|
|
|
void socket_receive_result(int fd, char *result, ssize_t result_len) {
|
|
ssize_t len;
|
|
len = xread(fd, result, result_len - 1);
|
|
result[len] = '\0';
|
|
}
|