freebsd-skq/sys/netinet/toecore.h
Navdeep Parhar 01d74fe1ff Path MTU discovery hooks for offloaded TCP connections.
Notify the TOE driver when when an ICMP type 3 code 4 (Fragmentation
needed and DF set) message is received for an offloaded connection.
This gives the driver an opportunity to lower the path MTU for the
connection and resume transmission, much like what the kernel does for
the connections that it handles.

Reviewed by:	glebius@
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D29755
2021-04-21 13:00:16 -07:00

149 lines
5.3 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2012 Chelsio Communications, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _NETINET_TOE_H_
#define _NETINET_TOE_H_
#ifndef _KERNEL
#error "no user-serviceable parts inside"
#endif
#include <netinet/tcp.h>
#include <sys/_eventhandler.h>
struct tcpopt;
struct tcphdr;
struct in_conninfo;
struct tcp_info;
struct nhop_object;
struct ktls_session;
struct toedev {
TAILQ_ENTRY(toedev) link; /* glue for toedev_list */
void *tod_softc; /* TOE driver private data */
/*
* Active open. If a failure occurs, it is reported back by the driver
* via toe_connect_failed.
*/
int (*tod_connect)(struct toedev *, struct socket *, struct nhop_object *,
struct sockaddr *);
/* Passive open. */
int (*tod_listen_start)(struct toedev *, struct tcpcb *);
int (*tod_listen_stop)(struct toedev *, struct tcpcb *);
/*
* The kernel uses this routine to pass on any frame it receives for an
* offloaded connection to the TOE driver. This is an unusual event.
*/
void (*tod_input)(struct toedev *, struct tcpcb *, struct mbuf *);
/*
* This is called by the kernel during pru_rcvd for an offloaded TCP
* connection and provides an opportunity for the TOE driver to manage
* its rx window and credits.
*/
void (*tod_rcvd)(struct toedev *, struct tcpcb *);
/*
* Transmit routine. The kernel calls this to have the TOE driver
* evaluate whether there is data to be transmitted, and transmit it.
*/
int (*tod_output)(struct toedev *, struct tcpcb *);
/* Immediate teardown: send RST to peer. */
int (*tod_send_rst)(struct toedev *, struct tcpcb *);
/* Initiate orderly disconnect by sending FIN to the peer. */
int (*tod_send_fin)(struct toedev *, struct tcpcb *);
/* Called to indicate that the kernel is done with this TCP PCB. */
void (*tod_pcb_detach)(struct toedev *, struct tcpcb *);
/*
* The kernel calls this once it has information about an L2 entry that
* the TOE driver enquired about previously (via toe_l2_resolve).
*/
void (*tod_l2_update)(struct toedev *, struct ifnet *,
struct sockaddr *, uint8_t *, uint16_t);
/* XXX. Route has been redirected. */
void (*tod_route_redirect)(struct toedev *, struct ifnet *,
struct nhop_object *, struct nhop_object *);
/* Syncache interaction. */
void (*tod_syncache_added)(struct toedev *, void *);
void (*tod_syncache_removed)(struct toedev *, void *);
int (*tod_syncache_respond)(struct toedev *, void *, struct mbuf *);
void (*tod_offload_socket)(struct toedev *, void *, struct socket *);
/* TCP socket option */
void (*tod_ctloutput)(struct toedev *, struct tcpcb *, int, int);
/* Update software state */
void (*tod_tcp_info)(struct toedev *, struct tcpcb *,
struct tcp_info *);
/* Create a TLS session */
int (*tod_alloc_tls_session)(struct toedev *, struct tcpcb *,
struct ktls_session *, int);
/* ICMP fragmentation-needed received, adjust PMTU. */
void (*tod_pmtu_update)(struct toedev *, struct tcpcb *, tcp_seq, int);
};
typedef void (*tcp_offload_listen_start_fn)(void *, struct tcpcb *);
typedef void (*tcp_offload_listen_stop_fn)(void *, struct tcpcb *);
EVENTHANDLER_DECLARE(tcp_offload_listen_start, tcp_offload_listen_start_fn);
EVENTHANDLER_DECLARE(tcp_offload_listen_stop, tcp_offload_listen_stop_fn);
void init_toedev(struct toedev *);
int register_toedev(struct toedev *);
int unregister_toedev(struct toedev *);
/*
* General interface for looking up L2 information for an IP address. If an
* answer is not available right away then the TOE driver's tod_l2_update will
* be called later.
*/
int toe_l2_resolve(struct toedev *, struct ifnet *, struct sockaddr *,
uint8_t *, uint16_t *);
void toe_connect_failed(struct toedev *, struct inpcb *, int);
void toe_syncache_add(struct in_conninfo *, struct tcpopt *, struct tcphdr *,
struct inpcb *, void *, void *, uint8_t);
int toe_syncache_expand(struct in_conninfo *, struct tcpopt *, struct tcphdr *,
struct socket **);
int toe_4tuple_check(struct in_conninfo *, struct tcphdr *, struct ifnet *);
#endif