treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206
[muen/linux.git] / tools / testing / selftests / bpf / test_dev_cgroup.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2017 Facebook
3  */
4
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include <errno.h>
9 #include <assert.h>
10 #include <sys/time.h>
11
12 #include <linux/bpf.h>
13 #include <bpf/bpf.h>
14 #include <bpf/libbpf.h>
15
16 #include "cgroup_helpers.h"
17 #include "bpf_rlimit.h"
18
19 #define DEV_CGROUP_PROG "./dev_cgroup.o"
20
21 #define TEST_CGROUP "/test-bpf-based-device-cgroup/"
22
23 int main(int argc, char **argv)
24 {
25         struct bpf_object *obj;
26         int error = EXIT_FAILURE;
27         int prog_fd, cgroup_fd;
28         __u32 prog_cnt;
29
30         if (bpf_prog_load(DEV_CGROUP_PROG, BPF_PROG_TYPE_CGROUP_DEVICE,
31                           &obj, &prog_fd)) {
32                 printf("Failed to load DEV_CGROUP program\n");
33                 goto out;
34         }
35
36         if (setup_cgroup_environment()) {
37                 printf("Failed to load DEV_CGROUP program\n");
38                 goto err;
39         }
40
41         /* Create a cgroup, get fd, and join it */
42         cgroup_fd = create_and_get_cgroup(TEST_CGROUP);
43         if (cgroup_fd < 0) {
44                 printf("Failed to create test cgroup\n");
45                 goto err;
46         }
47
48         if (join_cgroup(TEST_CGROUP)) {
49                 printf("Failed to join cgroup\n");
50                 goto err;
51         }
52
53         /* Attach bpf program */
54         if (bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_DEVICE, 0)) {
55                 printf("Failed to attach DEV_CGROUP program");
56                 goto err;
57         }
58
59         if (bpf_prog_query(cgroup_fd, BPF_CGROUP_DEVICE, 0, NULL, NULL,
60                            &prog_cnt)) {
61                 printf("Failed to query attached programs");
62                 goto err;
63         }
64
65         /* All operations with /dev/zero and and /dev/urandom are allowed,
66          * everything else is forbidden.
67          */
68         assert(system("rm -f /tmp/test_dev_cgroup_null") == 0);
69         assert(system("mknod /tmp/test_dev_cgroup_null c 1 3"));
70         assert(system("rm -f /tmp/test_dev_cgroup_null") == 0);
71
72         /* /dev/zero is whitelisted */
73         assert(system("rm -f /tmp/test_dev_cgroup_zero") == 0);
74         assert(system("mknod /tmp/test_dev_cgroup_zero c 1 5") == 0);
75         assert(system("rm -f /tmp/test_dev_cgroup_zero") == 0);
76
77         assert(system("dd if=/dev/urandom of=/dev/zero count=64") == 0);
78
79         /* src is allowed, target is forbidden */
80         assert(system("dd if=/dev/urandom of=/dev/full count=64"));
81
82         /* src is forbidden, target is allowed */
83         assert(system("dd if=/dev/random of=/dev/zero count=64"));
84
85         error = 0;
86         printf("test_dev_cgroup:PASS\n");
87
88 err:
89         cleanup_cgroup_environment();
90
91 out:
92         return error;
93 }