selinux_set_mapping(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLE | AUTHOR | SEE ALSO | COLOPHON

selinux_set_mapping(3)  SELinux API documentation selinux_set_mapping(3)

NAME         top

       selinux_set_mapping - establish dynamic object class and
       permission mapping

SYNOPSIS         top

       #include <selinux/selinux.h>

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

       int selinux_set_mapping(struct security_class_mapping *map);

DESCRIPTION         top

       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. If using this
       function, applications should also set a SELINUX_CB_POLICYLOAD
       callback via selinux_set_callback(3) that calls this function
       again upon a policy reload to re-create the mapping in case the
       class or permission values change in the new policy.  Generally
       it is preferred to instead use selinux_check_access(3) instead of
       avc_has_perm(3) or security_compute_av(3) and not use this
       function at all.

       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         top

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

ERRORS         top

       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         top

              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         top

       Originally Eamon Walsh.  Updated by Stephen Smalley
       <sds@tycho.nsa.gov>

SEE ALSO         top

       selinux_check_access(3), selinux_set_callback(3),
       avc_has_perm(3), selinux(8)

COLOPHON         top

       This page is part of the selinux (Security-Enhanced Linux user-
       space libraries and tools) project.  Information about the
       project can be found at 
       ⟨https://github.com/SELinuxProject/selinux/wiki⟩.  If you have a
       bug report for this manual page, see
       ⟨https://github.com/SELinuxProject/selinux/wiki/Contributing⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/SELinuxProject/selinux⟩ on 2021-04-01.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2021-03-18.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

                               12 Jun 2008        selinux_set_mapping(3)

Pages that refer to this page: avc_has_perm(3)security_compute_av(3)