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selabel_lookup_best_match(3SELinux API documentatiselabel_lookup_best_match(3)

NAME
       selabel_lookup_best_match  -  obtain a best match SELinux security con-
       text - Only supported on file backend.
SYNOPSIS
       #include <selinux/selinux.h>
       #include <selinux/label.h>
       int selabel_lookup_best_match(struct selabel_handle *hnd,
                                     char **context,
                                     const char *key,
                                     const char **links,
                                     int type);
       int selabel_lookup_best_match_raw(struct selabel_handle *hnd,
                                         char **context,
                                         const char *key,
                                         const char **links,
                                         int type);
DESCRIPTION
       selabel_lookup_best_match() performs a best match lookup  operation  on
       the  handle  hnd, returning the result in the memory pointed to by con-
       text, which must be freed by the  caller  using  freecon(3).   The  key
       parameter  is  a  file  path to check for best match using zero or more
       link (aliases) parameters. The order of precedence for best match is:
              1.  An exact match for the real path (key) or
              2.  An exact match for any of the links (aliases), or
              3.  The longest fixed prefix match.
       The type parameter is an optional file mode argument that should be set
       to  the  mode bits of the file, as determined by lstat(2).  mode may be
       zero, however full matching may not occur.
       selabel_lookup_best_match_raw()   behaves    identically    to    sela-
       bel_lookup_best_match() but does not perform context translation.
RETURN VALUE
       On  success,  zero  is returned.  On error, -1 is returned and errno is
       set appropriately.
ERRORS
       ENOENT No context corresponding to the input key and type was found.
       EINVAL The key and/or type inputs are invalid,  or  the  context  being
              returned failed validation.
       ENOMEM An attempt to allocate memory failed.

NOTES
       Example  usage - When a service creates a device node, it may also cre-
       ate one or more symlinks to the device node.  These symlinks may be the
       only  stable  name for the device, e.g. if the partition is dynamically
       assigned.  The file label backend supports this by looking up the "best
       match"  for a device node based on its real path (key) and any links to
       it (aliases). The order of  precedence  for  best  match  is  described
       above.

SEE ALSO
       selabel_open(3), selabel_stats(3), selinux_set_callback(3), selinux(8),
       lstat(2), selabel_file(5)

Security Enhanced Linux           05 May 2015     selabel_lookup_best_match(3)