97 lines
2.3 KiB
C
97 lines
2.3 KiB
C
|
/* Copyright (c) 2017 Facebook
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or
|
||
|
|
* modify it under the terms of version 2 of the GNU General Public
|
||
|
|
* License as published by the Free Software Foundation.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#include <assert.h>
|
||
|
|
#include <sys/time.h>
|
||
|
|
|
||
|
|
#include <linux/bpf.h>
|
||
|
|
#include <bpf/bpf.h>
|
||
|
|
#include <bpf/libbpf.h>
|
||
|
|
|
||
|
|
#include "cgroup_helpers.h"
|
||
|
|
#include "bpf_rlimit.h"
|
||
|
|
|
||
|
|
#define DEV_CGROUP_PROG "./dev_cgroup.o"
|
||
|
|
|
||
|
|
#define TEST_CGROUP "/test-bpf-based-device-cgroup/"
|
||
|
|
|
||
|
|
int main(int argc, char **argv)
|
||
|
|
{
|
||
|
|
struct bpf_object *obj;
|
||
|
|
int error = EXIT_FAILURE;
|
||
|
|
int prog_fd, cgroup_fd;
|
||
|
|
__u32 prog_cnt;
|
||
|
|
|
||
|
|
if (bpf_prog_load(DEV_CGROUP_PROG, BPF_PROG_TYPE_CGROUP_DEVICE,
|
||
|
|
&obj, &prog_fd)) {
|
||
|
|
printf("Failed to load DEV_CGROUP program\n");
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (setup_cgroup_environment()) {
|
||
|
|
printf("Failed to load DEV_CGROUP program\n");
|
||
|
|
goto err;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Create a cgroup, get fd, and join it */
|
||
|
|
cgroup_fd = create_and_get_cgroup(TEST_CGROUP);
|
||
|
|
if (!cgroup_fd) {
|
||
|
|
printf("Failed to create test cgroup\n");
|
||
|
|
goto err;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (join_cgroup(TEST_CGROUP)) {
|
||
|
|
printf("Failed to join cgroup\n");
|
||
|
|
goto err;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Attach bpf program */
|
||
|
|
if (bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_DEVICE, 0)) {
|
||
|
|
printf("Failed to attach DEV_CGROUP program");
|
||
|
|
goto err;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (bpf_prog_query(cgroup_fd, BPF_CGROUP_DEVICE, 0, NULL, NULL,
|
||
|
|
&prog_cnt)) {
|
||
|
|
printf("Failed to query attached programs");
|
||
|
|
goto err;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* All operations with /dev/zero and and /dev/urandom are allowed,
|
||
|
|
* everything else is forbidden.
|
||
|
|
*/
|
||
|
|
assert(system("rm -f /tmp/test_dev_cgroup_null") == 0);
|
||
|
|
assert(system("mknod /tmp/test_dev_cgroup_null c 1 3"));
|
||
|
|
assert(system("rm -f /tmp/test_dev_cgroup_null") == 0);
|
||
|
|
|
||
|
|
/* /dev/zero is whitelisted */
|
||
|
|
assert(system("rm -f /tmp/test_dev_cgroup_zero") == 0);
|
||
|
|
assert(system("mknod /tmp/test_dev_cgroup_zero c 1 5") == 0);
|
||
|
|
assert(system("rm -f /tmp/test_dev_cgroup_zero") == 0);
|
||
|
|
|
||
|
|
assert(system("dd if=/dev/urandom of=/dev/zero count=64") == 0);
|
||
|
|
|
||
|
|
/* src is allowed, target is forbidden */
|
||
|
|
assert(system("dd if=/dev/urandom of=/dev/full count=64"));
|
||
|
|
|
||
|
|
/* src is forbidden, target is allowed */
|
||
|
|
assert(system("dd if=/dev/random of=/dev/zero count=64"));
|
||
|
|
|
||
|
|
error = 0;
|
||
|
|
printf("test_dev_cgroup:PASS\n");
|
||
|
|
|
||
|
|
err:
|
||
|
|
cleanup_cgroup_environment();
|
||
|
|
|
||
|
|
out:
|
||
|
|
return error;
|
||
|
|
}
|