bionic (3) selinux_set_mapping.3.gz

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)