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