linux/net/handshake/trace.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Trace points for transport security layer handshakes.
 *
 * Author: Chuck Lever <chuck.lever@oracle.com>
 *
 * Copyright (c) 2023, Oracle and/or its affiliates.
 */

#include <linux/types.h>

#include <net/sock.h>
#include <net/netlink.h>
#include <net/genetlink.h>

#include "handshake.h"

#define CREATE_TRACE_POINTS

#include <trace/events/handshake.h>
net/handshake: Create a NETLINK service for handling handshake requests When a kernel consumer needs a transport layer security session, it first needs a handshake to negotiate and establish a session. This negotiation can be done in user space via one of the several existing library implementations, or it can be done in the kernel. No in-kernel handshake implementations yet exist. In their absence, we add a netlink service that can: a. Notify a user space daemon that a handshake is needed. b. Once notified, the daemon calls the kernel back via this netlink service to get the handshake parameters, including an open socket on which to establish the session. c. Once the handshake is complete, the daemon reports the session status and other information via a second netlink operation. This operation marks that it is safe for the kernel to use the open socket and the security session established there. The notification service uses a multicast group. Each handshake mechanism (eg, tlshd) adopts its own group number so that the handshake services are completely independent of one another. The kernel can then tell via netlink_has_listeners() whether a handshake service is active and prepared to handle a handshake request. A new netlink operation, ACCEPT, acts like accept(2) in that it instantiates a file descriptor in the user space daemon's fd table. If this operation is successful, the reply carries the fd number, which can be treated as an open and ready file descriptor. While user space is performing the handshake, the kernel keeps its muddy paws off the open socket. A second new netlink operation, DONE, indicates that the user space daemon is finished with the socket and it is safe for the kernel to use again. The operation also indicates whether a session was established successfully. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> 2023-04-17 10:32:26 -04:00			`// SPDX-License-Identifier: GPL-2.0`
			`/*`
			`* Trace points for transport security layer handshakes.`
			`*`
			`* Author: Chuck Lever <chuck.lever@oracle.com>`
			`*`
			`* Copyright (c) 2023, Oracle and/or its affiliates.`
			`*/`

			`#include <linux/types.h>`

			`#include <net/sock.h>`
			`#include <net/netlink.h>`
			`#include <net/genetlink.h>`

			`#include "handshake.h"`

			`#define CREATE_TRACE_POINTS`

			`#include <trace/events/handshake.h>`