1 #include <cap-ng.h>
2 #include <linux/capability.h>
3 #include <stdbool.h>
4 #include <string.h>
5 #include <stdio.h>
6 #include <sys/prctl.h>
7 #include <sys/auxv.h>
8 
9 #include "../kselftest.h"
10 
11 #ifndef PR_CAP_AMBIENT
12 #define PR_CAP_AMBIENT			47
13 # define PR_CAP_AMBIENT_IS_SET		1
14 # define PR_CAP_AMBIENT_RAISE		2
15 # define PR_CAP_AMBIENT_LOWER		3
16 # define PR_CAP_AMBIENT_CLEAR_ALL	4
17 #endif
18 
19 #if __GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 19)
20 # define HAVE_GETAUXVAL
21 #endif
22 
23 static bool bool_arg(char **argv, int i)
24 {
25 	if (!strcmp(argv[i], "0"))
26 		return false;
27 	else if (!strcmp(argv[i], "1"))
28 		return true;
29 	else {
30 		ksft_exit_fail_msg("wrong argv[%d]\n", i);
31 		return false;
32 	}
33 }
34 
35 int main(int argc, char **argv)
36 {
37 	const char *atsec = "";
38 
39 	/*
40 	 * Be careful just in case a setgid or setcapped copy of this
41 	 * helper gets out.
42 	 */
43 
44 	if (argc != 5)
45 		ksft_exit_fail_msg("wrong argc\n");
46 
47 #ifdef HAVE_GETAUXVAL
48 	if (getauxval(AT_SECURE))
49 		atsec = " (AT_SECURE is set)";
50 	else
51 		atsec = " (AT_SECURE is not set)";
52 #endif
53 
54 	capng_get_caps_process();
55 
56 	if (capng_have_capability(CAPNG_EFFECTIVE, CAP_NET_BIND_SERVICE) != bool_arg(argv, 1)) {
57 		ksft_print_msg("Wrong effective state%s\n", atsec);
58 		return 1;
59 	}
60 
61 	if (capng_have_capability(CAPNG_PERMITTED, CAP_NET_BIND_SERVICE) != bool_arg(argv, 2)) {
62 		ksft_print_msg("Wrong permitted state%s\n", atsec);
63 		return 1;
64 	}
65 
66 	if (capng_have_capability(CAPNG_INHERITABLE, CAP_NET_BIND_SERVICE) != bool_arg(argv, 3)) {
67 		ksft_print_msg("Wrong inheritable state%s\n", atsec);
68 		return 1;
69 	}
70 
71 	if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_IS_SET, CAP_NET_BIND_SERVICE, 0, 0, 0) != bool_arg(argv, 4)) {
72 		ksft_print_msg("Wrong ambient state%s\n", atsec);
73 		return 1;
74 	}
75 
76 	ksft_print_msg("%s: Capabilities after execve were correct\n",
77 			"validate_cap:");
78 	return 0;
79 }
80