tools/testing/selftests/capabilities/validate_cap.c

   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
  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
  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 }