membership.subproj/mbr_check_membership.3

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  29 .Dd November 5, 2011
  30 .Dt MBR_CHECK_MEMBERSHIP 3
  31 .Os "Mac OS X"
  32 .Sh NAME
  33 .Nm mbr_check_membership,
  34 .Nm mbr_check_service_membership
  35 .Nd check whether a user is a member of a group or service ACL
  36 .Sh SYNOPSIS
  37 .In membership.h
  38 .Ft int
  39 .Fn mbr_check_membership "uuid_t user" "uuid_t group" "int *ismember"
  40 .Ft int
  41 .Fn mbr_check_service_membership "uuid_t user" "const char *service" "int *ismember"
  42 .Sh DESCRIPTION
  43 .Fn mbr_check_membership
  44 tests if a given user is a member of a group (either direct or indirect via a
  45 nested group).
  46 .Fa ismember
  47 is set to 1 if the user is a member or 0 if not a member of the group.
  48 .Fn mbr_check_service_membership
  49 similarly tests if a given user is a member of a service ACL group.  Service
  50 ACLs are special groups defined with the prefix "com.apple.access_".  The
  51 service is then prefixed (e.g., "afp" would check "com.apple.access_afp").
  52 There is a special group that grants accessto all services called
  53 "com.apple.access_all_services".
  54 .Pp
  55 Users may belong to any number of groups.
  56 .Fn mbr_check_membership
  57 should always be used to check group membership, rather than calling
  58 .Xr getgroups 2
  59 or
  60 .Xr getgrouplist 2 .
  61 The
  62 .Xr setgroups 2
  63 and
  64 .Xr getgroups 2
  65 routines are limited to a fixed number of gids,
  66 and so may not include all of a user's groups.
  67 .Pp
  68 There are two special cases.
  69 If the two uuids are equal, then
  70 .Fa ismember
  71 is set to 1.
  72 If the
  73 .Fa group
  74 uuid is equal to the reserved "everyone" uuid (ABCDEFAB-CDEF-ABCD-EFAB-CDEF0000000C), then
  75 .Fa ismember
  76 will be set to 1 for any valid user.
  77 .Pp
  78 Group membership information is managed by
  79 .Xr opendirectoryd 8 .
  80 .Sh RETURN VALUES
  81 .Fn mbr_check_membership
  82 does not test whether
  83 .Fa group
  84 exists or not.
  85 Querying membership for a nonexistent group will result in
  86 .Fa ismember
  87 being set to 0.  The function returns 0 on success or one of the following error
  88 codes on failure:
  89 .Bl -tag -width Er
  90 .It Bq Er EIO
  91 Communication with
  92 .Xr openditectoryd 8
  93 failed.
  94 .It Bq Er ENOENT
  95 .Fa user
  96 can not be found.
  97 .El
  98 .Pp
  99 .Fn mbr_check_service_membership
 100 is identical to
 101 .Fn mbr_check_membership
 102 except that ENOENT means no service ACL has been defined.
 103 .Pp
 104 .Sh SEE ALSO
 105 .Xr odutil 1 ,
 106 .Xr setgroups 2 ,
 107 .Xr getgroups 2 ,
 108 .Xr mbr_uid_to_uuid 3 ,
 109 .Xr opendirectoryd 8