xref: /linux/tools/testing/selftests/capabilities/validate_cap.c (revision 20dfee95936413708701eb151f419597fdd9d948)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <cap-ng.h>
3 #include <linux/capability.h>
4 #include <stdbool.h>
5 #include <string.h>
6 #include <stdio.h>
7 #include <sys/prctl.h>
8 #include <sys/auxv.h>
9 
10 #include "../kselftest.h"
11 
12 #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 19)
13 # define HAVE_GETAUXVAL
14 #endif
15 
16 static bool bool_arg(char **argv, int i)
17 {
18 	if (!strcmp(argv[i], "0"))
19 		return false;
20 	else if (!strcmp(argv[i], "1"))
21 		return true;
22 	else {
23 		ksft_exit_fail_msg("wrong argv[%d]\n", i);
24 		return false;
25 	}
26 }
27 
28 int main(int argc, char **argv)
29 {
30 	const char *atsec = "";
31 	int ret;
32 
33 	/*
34 	 * Be careful just in case a setgid or setcapped copy of this
35 	 * helper gets out.
36 	 */
37 
38 	if (argc != 5)
39 		ksft_exit_fail_msg("wrong argc\n");
40 
41 #ifdef HAVE_GETAUXVAL
42 	if (getauxval(AT_SECURE))
43 		atsec = " (AT_SECURE is set)";
44 	else
45 		atsec = " (AT_SECURE is not set)";
46 #endif
47 
48 	ret = capng_get_caps_process();
49 	if (ret == -1) {
50 		ksft_print_msg("capng_get_caps_process failed\n");
51 		return 1;
52 	}
53 
54 	if (capng_have_capability(CAPNG_EFFECTIVE, CAP_NET_BIND_SERVICE) != bool_arg(argv, 1)) {
55 		ksft_print_msg("Wrong effective state%s\n", atsec);
56 		return 1;
57 	}
58 
59 	if (capng_have_capability(CAPNG_PERMITTED, CAP_NET_BIND_SERVICE) != bool_arg(argv, 2)) {
60 		ksft_print_msg("Wrong permitted state%s\n", atsec);
61 		return 1;
62 	}
63 
64 	if (capng_have_capability(CAPNG_INHERITABLE, CAP_NET_BIND_SERVICE) != bool_arg(argv, 3)) {
65 		ksft_print_msg("Wrong inheritable state%s\n", atsec);
66 		return 1;
67 	}
68 
69 	if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_IS_SET, CAP_NET_BIND_SERVICE, 0, 0, 0) != bool_arg(argv, 4)) {
70 		ksft_print_msg("Wrong ambient state%s\n", atsec);
71 		return 1;
72 	}
73 
74 	ksft_print_msg("%s: Capabilities after execve were correct\n",
75 			"validate_cap:");
76 	return 0;
77 }
78