"selabel_lookup_best_match" "3" "05 May 2015" "Security Enhanced Linux" "SELinux API documentation"
"NAME"
selabel_lookup_best_match - obtain a best match SELinux security
context - 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
context , 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." 4
An exact match for the real path (key) or
"2." 4
An exact match for any of the links (aliases), or
"3." 4
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
selabel_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 create 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)
