selabel_media(5) SELinux API documentation selabel_media(5)
NAME
selabel_media - userspace SELinux labeling interface and configuration file format for the media contexts backend
SYNOPSIS
#include <selinux/label.h>
int selabel_lookup(struct selabel_handle *hnd,
security_context_t *context,
const char *device_name, int unused);
int selabel_lookup_raw(struct selabel_handle *hnd,
security_context_t *context,
const char *device_name, int unused);
DESCRIPTION
The media contexts backend maps from media device names such as "cdrom" or "floppy" into security contexts. It is used to find the appro-
priate context for establishing context mounts on these devices. The returned context must be freed using freecon(3).
selabel_lookup(3) describes the function with its return and error codes.
The integer lookup argument is currently unused and should be set to zero.
Any messages generated by selabel_lookup(3) are sent to stderr by default, although this can be changed by selinux_set_callback(3).
selabel_lookup_raw(3) behaves identically to selabel_lookup(3) but does not perform context translation.
The FILES section details the configuration files used to determine the media context.
OPTIONS
In addition to the global options described in selabel_open(3), this backend recognizes the following options:
SELABEL_OPT_PATH
A non-null value for this option specifies a path to a file that will be opened in lieu of the standard media contexts file.
FILES
The media context file used to retrieve a default context depends on the SELABEL_OPT_PATH parameter passed to selabel_open(3). If NULL,
then the SELABEL_OPT_PATH value will default to the active policy media contexts location (as returned by selinux_media_context_path(3)),
otherwise the actual SELABEL_OPT_PATH value specified is used.
The default media contexts file is:
/etc/selinux/{SELINUXTYPE}/contexts/files/media
Where {SELINUXTYPE} is the entry from the selinux configuration file config (see selinux_config(5)).
Should there not be a valid entry in the media file, then the default removable_context file will be read (see removable_context(5)).
FILE FORMAT
Each line within the media file is as follows:
device_name context
Where:
device_name
The media identifier (e.g. cdrom, floppy, disk and usb).
context
The context to be used for labeling the device.
Example:
# contexts/files/media
cdrom system_u:object_r:removable_device_t
floppy system_u:object_r:removable_device_t
disk system_u:object_r:fixed_disk_device_t
NOTES
If contexts are to be validated, then the global option SELABEL_OPT_VALIDATE must be set before calling selabel_open(3). If this is not
set, then it is possible for an invalid context to be returned.
SEE ALSO
selinux(8), selabel_open(3), selabel_lookup(3), selabel_stats(3), selabel_close(3), selinux_set_callback(3), selinux_media_context_path(3),
freecon(3), selinux_config(5), removable_context(5)
Security Enhanced Linux 29 Nov 2011 selabel_media(5)
