historical/me-disable-modern.git/mei-disable.c
2024-01-16 11:20:27 -06:00

104 lines
2.1 KiB
C

#include <stdio.h>
#include <fcntl.h>
#include <inttypes.h>
#include <sys/ioctl.h>
#include <linux/mei.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
// Disable Intel ME engine.
// This was tested on Z87 board.
// Payload data taken from reverse-engineered fpt.exe v9.5.
struct guid
{
uint32_t data1;
uint16_t data2;
uint16_t data3;
uint8_t data4[8];
};
static const struct guid mkhi_guid = {
0x8E6A6715,
0x9ABC,
0x4043,
{0x88, 0xEF, 0x9E, 0x39, 0xC6, 0xF6, 0x3E, 0x0F}
};
uint8_t disable_cmd[] = {0xff,0x10,0x00,0x00};
#define NUM_DEV_NAMES 5
char *DEF_DEV_NAMES[NUM_DEV_NAMES] = {"/dev/mei0", "/dev/mei", "/dev/mei1", "/dev/mei2", "/dev/mei3"};
char *imeCheck() {
char *dev_name = NULL;
struct stat st;
for (int i = 0; i < NUM_DEV_NAMES; i++) {
char path[20];
snprintf(path, sizeof(path), "%s", DEF_DEV_NAMES[i]);
if (stat(path, &st) == 0) {
dev_name = DEF_DEV_NAMES[i];
break;
}
}
if (dev_name == NULL) {
perror("ME Device not found.\n");
exit(1);
}
printf("Found ME device!\n");
return dev_name;
}
int main(int argc, char *argv[])
{
int fd;
int rc;
int i;
struct mei_connect_client_data meidata;
char *DEV_NAME = imeCheck();
printf("Opening %s ... ", DEV_NAME);
fd = open(DEV_NAME, O_RDWR);
if (fd < 0) {
printf("error\n"); fflush(stdout);
perror("mei device open");
return 1;
}
printf("opened\n");
memcpy(&meidata.in_client_uuid,&mkhi_guid,sizeof(mkhi_guid));
printf("Sending IOCTL_MEI_CONNECT_CLIENT .. ");
rc = ioctl(fd, IOCTL_MEI_CONNECT_CLIENT, &meidata);
if (rc < 0) {
printf("error\n"); fflush(stdout);
perror("ioctl");
close(fd);
return 1;
}
printf("ok\n");
printf("Writing disableme payload .. ");
rc = write(fd, disable_cmd, sizeof(disable_cmd));
if (rc < 0) {
printf("error\n"); fflush(stdout);
perror("write");
close(fd);
return 1;
}
fsync(fd);
printf("written %d bytes\n",rc);
printf("Sleep 1 sec\n",rc);
sleep(1);
close(fd);
return 0;
}