landlock.c

 1/* SPDX-License-Identifier: GPL-2.0 */
 2#include <linux/compiler.h>
 3#include <linux/types.h>
 4#include <unistd.h>
 5#include "../tests.h"
 6
 7/* This workload was initially added to test enum augmentation with BTF in perf
 8 * trace because its the only syscall that has an enum argument. Since it is
 9 * a recent addition to the Linux kernel (at the time of the introduction of this
10 * 'perf test' workload) we just add the required types and defines here instead
11 * of including linux/landlock, that isn't available in older systems.
12 *
13 * We are not interested in the result of the syscall, just in intercepting
14 * its arguments.
15 */
16
17#ifndef __NR_landlock_add_rule
18#define __NR_landlock_add_rule 445
19#endif
20
21#ifndef LANDLOCK_ACCESS_FS_READ_FILE
22#define LANDLOCK_ACCESS_FS_READ_FILE	(1ULL << 2)
23
24#define LANDLOCK_RULE_PATH_BENEATH	1
25
26struct landlock_path_beneath_attr {
27        __u64 allowed_access;
28        __s32 parent_fd;
29};
30#endif
31
32#ifndef LANDLOCK_ACCESS_NET_CONNECT_TCP
33#define LANDLOCK_ACCESS_NET_CONNECT_TCP	(1ULL << 1)
34
35#define LANDLOCK_RULE_NET_PORT		2
36
37struct landlock_net_port_attr {
38	__u64 allowed_access;
39	__u64 port;
40};
41#endif
42
43static int landlock(int argc __maybe_unused, const char **argv __maybe_unused)
44{
45	int fd = 11, flags = 45;
46
47	struct landlock_path_beneath_attr path_beneath_attr = {
48		.allowed_access = LANDLOCK_ACCESS_FS_READ_FILE,
49		.parent_fd = 14,
50	};
51
52	struct landlock_net_port_attr net_port_attr = {
53		.port = 19,
54		.allowed_access = LANDLOCK_ACCESS_NET_CONNECT_TCP,
55	};
56
57	syscall(__NR_landlock_add_rule, fd, LANDLOCK_RULE_PATH_BENEATH,
58		&path_beneath_attr, flags);
59
60	syscall(__NR_landlock_add_rule, fd, LANDLOCK_RULE_NET_PORT,
61		&net_port_attr, flags);
62
63	return 0;
64}
65
66DEFINE_WORKLOAD(landlock);