config/kernel-userns-capabilities.m4

   1 dnl #
   2 dnl # 2.6.38 API change
   3 dnl # ns_capable() was introduced
   4 dnl #
   5 AC_DEFUN([ZFS_AC_KERNEL_NS_CAPABLE], [
   6         AC_MSG_CHECKING([whether ns_capable exists])
   7         ZFS_LINUX_TRY_COMPILE([
   8                 #include <linux/capability.h>
   9         ],[
  10                 ns_capable((struct user_namespace *)NULL, CAP_SYS_ADMIN);
  11         ],[
  12                 AC_MSG_RESULT(yes)
  13                 AC_DEFINE(HAVE_NS_CAPABLE, 1,
  14                     [ns_capable exists])
  15         ],[
  16                 AC_MSG_RESULT(no)
  17         ])
  18 ])
  19
  20 dnl #
  21 dnl # 2.6.39 API change
  22 dnl # struct user_namespace was added to struct cred_t as
  23 dnl # cred->user_ns member
  24 dnl # Note that current_user_ns() was added in 2.6.28.
  25 dnl #
  26 AC_DEFUN([ZFS_AC_KERNEL_CRED_USER_NS], [
  27         AC_MSG_CHECKING([whether cred_t->user_ns exists])
  28         ZFS_LINUX_TRY_COMPILE([
  29                 #include <linux/cred.h>
  30         ],[
  31                 struct cred cr;
  32                 cr.user_ns = (struct user_namespace *)NULL;
  33         ],[
  34                 AC_MSG_RESULT(yes)
  35                 AC_DEFINE(HAVE_CRED_USER_NS, 1,
  36                     [cred_t->user_ns exists])
  37         ],[
  38                 AC_MSG_RESULT(no)
  39         ])
  40 ])
  41
  42 dnl #
  43 dnl # 3.4 API change
  44 dnl # kuid_has_mapping() and kgid_has_mapping() were added to distinguish
  45 dnl # between internal kernel uids/gids and user namespace uids/gids.
  46 dnl #
  47 AC_DEFUN([ZFS_AC_KERNEL_KUID_HAS_MAPPING], [
  48         AC_MSG_CHECKING([whether kuid_has_mapping/kgid_has_mapping exist])
  49         ZFS_LINUX_TRY_COMPILE([
  50                 #include <linux/uidgid.h>
  51         ],[
  52                 kuid_has_mapping((struct user_namespace *)NULL, KUIDT_INIT(0));
  53                 kgid_has_mapping((struct user_namespace *)NULL, KGIDT_INIT(0));
  54         ],[
  55                 AC_MSG_RESULT(yes)
  56                 AC_DEFINE(HAVE_KUID_HAS_MAPPING, 1,
  57                     [kuid_has_mapping/kgid_has_mapping exist])
  58         ],[
  59                 AC_MSG_RESULT(no)
  60         ])
  61 ])
  62
  63 AC_DEFUN([ZFS_AC_KERNEL_USERNS_CAPABILITIES], [
  64         ZFS_AC_KERNEL_NS_CAPABLE
  65         ZFS_AC_KERNEL_CRED_USER_NS
  66         ZFS_AC_KERNEL_KUID_HAS_MAPPING
  67 ])