tools/testing/selftests/capabilities/validate_cap.c

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