NAME

       selinux_set_mapping - establish dynamic object class and permission mapping

SYNOPSIS

       #include <selinux/selinux.h>

       struct security_class_mapping {
            const char *name;
            const char *perms[];
       };

       int selinux_set_mapping(struct security_class_mapping *map);

DESCRIPTION

       selinux_set_mapping()  establishes  a  mapping  from  a  user-provided  ordering of object
       classes and permissions to the numbers actually used by the loaded system policy.  Use  of
       this  function  is  highly preferred over the generated constants in the libselinux header
       files, as this method allows the policy's class and permission values to change over time.

       After the mapping is established, all libselinux  functions  that  operate  on  class  and
       permission values take the user-provided numbers, which are determined as follows:

       The  map argument consists of an array of security_class_mapping structures, which must be
       terminated by a structure having a NULL name field.  Except for this last  structure,  the
       name field should refer to the string name of an object class, and the corresponding perms
       field should refer to an array of permission bit names terminated by a NULL string.

       The object classes named in the mapping and the bit indexes of each set of permission bits
       named  in the mapping are numbered in order starting from 1.  These numbers are the values
       that should be passed to subsequent libselinux calls.

RETURN VALUE

       Zero is returned on success.  On error, -1 is returned and errno is set appropriately.

ERRORS

       EINVAL One of the class or permission names requested in the mapping is not present in the
              loaded policy.

       ENOMEM An attempt to allocate memory failed.

EXAMPLE

              struct security_class_mapping map[] = {
                  { "file", { "create", "unlink", "read", "write", NULL } },
                  { "socket", { "bind", NULL } },
                  { "process", { "signal", NULL } },
                  { NULL }
              };

              if (selinux_set_mapping(map) < 0)
                  exit(1);

       In  this  example, after the call has succeeded, classes file, socket, and process will be
       identified by 1, 2 and 3, respectively.  Permissions create, unlink, read, and write  (for
       the  file  class)  will  be  identified  by  1,  2,  4,  and  8 respectively.  Classes and
       permissions not listed in the mapping cannot be used.

AUTHOR

       Eamon Walsh <ewalsh@tycho.nsa.gov>

SEE ALSO

       avc_open(8), selinux(8)

                                           12 Jun 2008                     selinux_set_mapping(3)