freebsd-nq/sys/netinet6/in6_rmx.c
Alexander V. Chernikov 9e02229580 Remove now-unused rt_ifp,rt_ifa,rt_gateway,rt_mtu rte fields.
After converting routing subsystem customers to use nexthop objects
 defined in r359823, some fields in struct rtentry became unused.

This commit removes rt_ifp, rt_ifa, rt_gateway and rt_mtu from struct rtentry
 along with the code initializing and updating these fields.

Cleanup of the remaining fields will be addressed by D24669.

This commit also changes the implementation of the RTM_CHANGE handling.
Old implementation tried to perform the whole operation under radix WLOCK,
 resulting in slow performance and hacks like using RTF_RNH_LOCKED flag.
New implementation looks up the route nexthop under radix RLOCK, creates new
 nexthop and tries to update rte nhop pointer. Only last part is done under
 WLOCK.
In the hypothetical scenarious where multiple rtsock clients
 repeatedly issue RTM_CHANGE requests for the same route, route may get
 updated between read and update operation. This is addressed by retrying
 the operation multiple (3) times before returning failure back to the
 caller.

Differential Revision:	https://reviews.freebsd.org/D24666
2020-05-04 14:31:45 +00:00

190 lines
5.7 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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.
*
* $KAME: in6_rmx.c,v 1.11 2001/07/26 06:53:16 jinmei Exp $
*/
/*-
* Copyright 1994, 1995 Massachusetts Institute of Technology
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby
* granted, provided that both the above copyright notice and this
* permission notice appear in all copies, that both the above
* copyright notice and this permission notice appear in all
* supporting documentation, and that the name of M.I.T. not be used
* in advertising or publicity pertaining to distribution of the
* software without specific, written prior permission. M.I.T. makes
* no representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
*
* THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
* ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
* SHALL M.I.T. 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.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_mpath.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/mbuf.h>
#include <sys/rwlock.h>
#include <sys/syslog.h>
#include <sys/callout.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/route/route_var.h>
#include <net/route/nhop.h>
#include <net/route/shared.h>
#include <netinet/in.h>
#include <netinet/ip_var.h>
#include <netinet/in_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>
#include <netinet6/nd6.h>
#include <netinet/tcp.h>
#include <netinet/tcp_seq.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
extern int in6_inithead(void **head, int off, u_int fibnum);
#ifdef VIMAGE
extern int in6_detachhead(void **head, int off);
#endif
static int
rib6_preadd(u_int fibnum, const struct sockaddr *addr, const struct sockaddr *mask,
struct nhop_object *nh)
{
uint16_t nh_type;
/* XXX: RTF_LOCAL */
/*
* Check route MTU:
* inherit interface MTU if not set or
* check if MTU is too large.
*/
if (nh->nh_mtu == 0) {
nh->nh_mtu = IN6_LINKMTU(nh->nh_ifp);
} else if (nh->nh_mtu > IN6_LINKMTU(nh->nh_ifp))
nh->nh_mtu = IN6_LINKMTU(nh->nh_ifp);
/* Ensure that default route nhop has special flag */
const struct sockaddr_in6 *mask6 = (const struct sockaddr_in6 *)mask;
if ((nhop_get_rtflags(nh) & RTF_HOST) == 0 && mask6 != NULL &&
IN6_IS_ADDR_UNSPECIFIED(&mask6->sin6_addr))
nh->nh_flags |= NHF_DEFAULT;
/* Set nexthop type */
if (nhop_get_type(nh) == 0) {
if (nh->nh_flags & NHF_GATEWAY)
nh_type = NH_TYPE_IPV6_ETHER_NHOP;
else
nh_type = NH_TYPE_IPV6_ETHER_RSLV;
nhop_set_type(nh, nh_type);
}
return (0);
}
/*
* Initialize our routing tree.
*/
int
in6_inithead(void **head, int off, u_int fibnum)
{
struct rib_head *rh;
rh = rt_table_init(offsetof(struct sockaddr_in6, sin6_addr) << 3,
AF_INET6, fibnum);
if (rh == NULL)
return (0);
rh->rnh_preadd = rib6_preadd;
#ifdef RADIX_MPATH
rt_mpath_init_rnh(rh);
#endif
*head = (void *)rh;
return (1);
}
#ifdef VIMAGE
int
in6_detachhead(void **head, int off)
{
rt_table_destroy((struct rib_head *)(*head));
return (1);
}
#endif
/*
* Extended API for IPv6 FIB support.
*/
int
in6_rtrequest(int req, struct sockaddr *dst, struct sockaddr *gw,
struct sockaddr *mask, int flags, struct rtentry **ret_nrt, u_int fibnum)
{
return (rtrequest_fib(req, dst, gw, mask, flags, ret_nrt, fibnum));
}