avc_netlink_open, avc_netlink_close, avc_netlink_acquire_fd,
avc_netlink_release_fd, avc_netlink_check_nb, avc_netlink_loop - SELinux
netlink processing
#include <selinux/selinux.h>
#include <selinux/avc.h>
int avc_netlink_open(int blocking);
void avc_netlink_close(void);
int avc_netlink_acquire_fd(void);
void avc_netlink_release_fd(void);
void avc_netlink_loop(void);
int avc_netlink_check_nb(void);
These functions enable applications to handle notification of SELinux events via
netlink. The userspace AVC normally checks for netlink messages on each call
to
avc_has_perm(3). Applications may wish to override this behavior and
check for notification separately, for example in a
select(2) loop.
These functions also permit netlink monitoring without requiring a call to
avc_open(3).
avc_netlink_open() opens a netlink socket to receive SELinux
notifications. The socket descriptor is stored internally; use
avc_netlink_acquire_fd(3) to take ownership of it in application code.
The
blocking argument controls whether the O_NONBLOCK flag is set on
the socket descriptor.
avc_open(3) calls this function internally,
specifying non-blocking behavior.
avc_netlink_close() closes the netlink socket. This function is called
automatically by
avc_destroy(3).
avc_netlink_acquire_fd() returns the netlink socket descriptor number and
informs the userspace AVC not to check the socket descriptor automatically on
calls to
avc_has_perm(3). If no such socket descriptor exists,
avc_netlink_acquire_fd(3) will first call
and then return the resulting fd.
avc_netlink_release_fd() returns control of the netlink socket to the
userspace AVC, re-enabling automatic processing of notifications.
avc_netlink_check_nb() checks the netlink socket for pending messages and
processes them. Callbacks for policyload and enforcing changes will be called;
see
selinux_set_callback(3). This function does not block.
avc_netlink_loop() enters a loop blocking on the netlink socket and
processing messages as they are received. This function will not return unless
an error occurs on the socket, in which case the socket is closed.
avc_netlink_acquire_fd() returns a non-negative file descriptor number on
success. Other functions with a return value return zero on success. On error,
-1 is returned and
errno is set appropriately.
Originally KaiGai Kohei. Updated by Mike Palmiotto
<
[email protected]>
avc_open(3),
selinux_set_callback(3),
selinux(8)