/*-
* 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.
*
*/
/*
* This code does two things necessary for the enhanced TCP metrics to
* function in a useful manner:
* 1) It marks all non-host routes as `cloning', thus ensuring that
* every actual reference to such a route actually gets turned
* into a reference to a host route to the specific destination
* requested.
* 2) When such routes lose all their references, it arranges for them
* to be deleted in some random collection of circumstances, so that
* a large quantity of stale routing data is not kept in kernel memory
* indefinitely. See in6_rtqtimo() below for the exact mechanism.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/sysctl.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/route.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);
#ifdef VIMAGE
extern int in6_detachhead(void **head, int off);
#endif
#define RTPRF_OURS RTF_PROTO3 /* set on routes we manage */
/*
* Do what we need to do when inserting a route.
*/
static struct radix_node *
in6_addroute(void *v_arg, void *n_arg, struct radix_node_head *head,
struct radix_node *treenodes)
{
struct rtentry *rt = (struct rtentry *)treenodes;
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)rt_key(rt);
struct radix_node *ret;
RADIX_NODE_HEAD_WLOCK_ASSERT(head);
if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
rt->rt_flags |= RTF_MULTICAST;
/*
* A little bit of help for both IPv6 output and input:
* For local addresses, we make sure that RTF_LOCAL is set,
* with the thought that this might one day be used to speed up
* ip_input().
*
* We also mark routes to multicast addresses as such, because
* it's easy to do and might be useful (but this is much more
* dubious since it's so easy to inspect the address). (This
* is done above.)
*
* XXX
* should elaborate the code.
*/
if (rt->rt_flags & RTF_HOST) {
if (IN6_ARE_ADDR_EQUAL(&satosin6(rt->rt_ifa->ifa_addr)
->sin6_addr,
&sin6->sin6_addr)) {
rt->rt_flags |= RTF_LOCAL;
}
}
if (!rt->rt_rmx.rmx_mtu && rt->rt_ifp)
rt->rt_rmx.rmx_mtu = IN6_LINKMTU(rt->rt_ifp);
ret = rn_addroute(v_arg, n_arg, head, treenodes);
if (ret == NULL) {
struct rtentry *rt2;
/*
* We are trying to add a net route, but can't.
* The following case should be allowed, so we'll make a
* special check for this:
* Two IPv6 addresses with the same prefix is assigned
* to a single interrface.
* # ifconfig if0 inet6 3ffe:0501::1 prefix 64 alias (*1)
* # ifconfig if0 inet6 3ffe:0501::2 prefix 64 alias (*2)
* In this case, (*1) and (*2) want to add the same
* net route entry, 3ffe:0501:: -> if0.
* This case should not raise an error.
*/
rt2 = rtalloc1((struct sockaddr *)sin6, 0, RTF_RNH_LOCKED);
if (rt2) {
if (((rt2->rt_flags & (RTF_HOST|RTF_GATEWAY)) == 0)
&& rt2->rt_gateway
&& rt2->rt_gateway->sa_family == AF_LINK
&& rt2->rt_ifp == rt->rt_ifp) {
ret = rt2->rt_nodes;
}
RTFREE_LOCKED(rt2);
}
}
return (ret);
}
/*
* This code is the inverse of in6_clsroute: on first reference, if we
* were managing the route, stop doing so and set the expiration timer
* back off again.
*/
static struct radix_node *
in6_matroute(void *v_arg, struct radix_node_head *head)
{
struct radix_node *rn = rn_match(v_arg, head);
struct rtentry *rt = (struct rtentry *)rn;
if (rt && rt->rt_refcnt == 0) { /* this is first reference */
if (rt->rt_flags & RTPRF_OURS) {
rt->rt_flags &= ~RTPRF_OURS;
rt->rt_rmx.rmx_expire = 0;
}
}
return rn;
}
SYSCTL_DECL(_net_inet6_ip6);
static VNET_DEFINE(int, rtq_reallyold6) = 60*60;
/* one hour is ``really old'' */
#define V_rtq_reallyold6 VNET(rtq_reallyold6)
SYSCTL_VNET_INT(_net_inet6_ip6, IPV6CTL_RTEXPIRE, rtexpire, CTLFLAG_RW,
&VNET_NAME(rtq_reallyold6) , 0, "");
static VNET_DEFINE(int, rtq_minreallyold6) = 10;
/* never automatically crank down to less */
#define V_rtq_minreallyold6 VNET(rtq_minreallyold6)
SYSCTL_VNET_INT(_net_inet6_ip6, IPV6CTL_RTMINEXPIRE, rtminexpire, CTLFLAG_RW,
&VNET_NAME(rtq_minreallyold6) , 0, "");
static VNET_DEFINE(int, rtq_toomany6) = 128;
/* 128 cached routes is ``too many'' */
#define V_rtq_toomany6 VNET(rtq_toomany6)
SYSCTL_VNET_INT(_net_inet6_ip6, IPV6CTL_RTMAXCACHE, rtmaxcache, CTLFLAG_RW,
&VNET_NAME(rtq_toomany6) , 0, "");
struct rtqk_arg {
struct radix_node_head *rnh;
int mode;
int updating;
int draining;
int killed;
int found;
time_t nextstop;
};
/*
* Get rid of old routes. When draining, this deletes everything, even when
* the timeout is not expired yet. When updating, this makes sure that
* nothing has a timeout longer than the current value of rtq_reallyold6.
*/
static int
in6_rtqkill(struct radix_node *rn, void *rock)
{
struct rtqk_arg *ap = rock;
struct rtentry *rt = (struct rtentry *)rn;
int err;
RADIX_NODE_HEAD_WLOCK_ASSERT(ap->rnh);
if (rt->rt_flags & RTPRF_OURS) {
ap->found++;
if (ap->draining || rt->rt_rmx.rmx_expire <= time_uptime) {
if (rt->rt_refcnt > 0)
panic("rtqkill route really not free");
err = rtrequest(RTM_DELETE,
(struct sockaddr *)rt_key(rt),
rt->rt_gateway, rt_mask(rt),
rt->rt_flags|RTF_RNH_LOCKED, 0);
if (err) {
log(LOG_WARNING, "in6_rtqkill: error %d", err);
} else {
ap->killed++;
}
} else {
if (ap->updating
&& (rt->rt_rmx.rmx_expire - time_uptime
> V_rtq_reallyold6)) {
rt->rt_rmx.rmx_expire = time_uptime
+ V_rtq_reallyold6;
}
ap->nextstop = lmin(ap->nextstop,
rt->rt_rmx.rmx_expire);
}
}
return 0;
}
#define RTQ_TIMEOUT 60*10 /* run no less than once every ten minutes */
static VNET_DEFINE(int, rtq_timeout6) = RTQ_TIMEOUT;
static VNET_DEFINE(struct callout, rtq_timer6);
#define V_rtq_timeout6 VNET(rtq_timeout6)
#define V_rtq_timer6 VNET(rtq_timer6)
static void
in6_rtqtimo(void *rock)
{
CURVNET_SET_QUIET((struct vnet *) rock);
struct radix_node_head *rnh;
struct rtqk_arg arg;
struct timeval atv;
static time_t last_adjusted_timeout = 0;
rnh = rt_tables_get_rnh(0, AF_INET6);
if (rnh == NULL) {
CURVNET_RESTORE();
return;
}
arg.found = arg.killed = 0;
arg.rnh = rnh;
arg.nextstop = time_uptime + V_rtq_timeout6;
arg.draining = arg.updating = 0;
RADIX_NODE_HEAD_LOCK(rnh);
rnh->rnh_walktree(rnh, in6_rtqkill, &arg);
RADIX_NODE_HEAD_UNLOCK(rnh);
/*
* Attempt to be somewhat dynamic about this:
* If there are ``too many'' routes sitting around taking up space,
* then crank down the timeout, and see if we can't make some more
* go away. However, we make sure that we will never adjust more
* than once in rtq_timeout6 seconds, to keep from cranking down too
* hard.
*/
if ((arg.found - arg.killed > V_rtq_toomany6)
&& (time_uptime - last_adjusted_timeout >= V_rtq_timeout6)
&& V_rtq_reallyold6 > V_rtq_minreallyold6) {
V_rtq_reallyold6 = 2*V_rtq_reallyold6 / 3;
if (V_rtq_reallyold6 < V_rtq_minreallyold6) {
V_rtq_reallyold6 = V_rtq_minreallyold6;
}
last_adjusted_timeout = time_uptime;
#ifdef DIAGNOSTIC
log(LOG_DEBUG, "in6_rtqtimo: adjusted rtq_reallyold6 to %d",
V_rtq_reallyold6);
#endif
arg.found = arg.killed = 0;
arg.updating = 1;
RADIX_NODE_HEAD_LOCK(rnh);
rnh->rnh_walktree(rnh, in6_rtqkill, &arg);
RADIX_NODE_HEAD_UNLOCK(rnh);
}
atv.tv_usec = 0;
atv.tv_sec = arg.nextstop - time_uptime;
callout_reset(&V_rtq_timer6, tvtohz(&atv), in6_rtqtimo, rock);
CURVNET_RESTORE();
}
/*
* Age old PMTUs.
*/
struct mtuex_arg {
struct radix_node_head *rnh;
time_t nextstop;
};
static VNET_DEFINE(struct callout, rtq_mtutimer);
#define V_rtq_mtutimer VNET(rtq_mtutimer)
static int
in6_mtuexpire(struct radix_node *rn, void *rock)
{
struct rtentry *rt = (struct rtentry *)rn;
struct mtuex_arg *ap = rock;
/* sanity */
if (!rt)
panic("rt == NULL in in6_mtuexpire");
if (rt->rt_rmx.rmx_expire && !(rt->rt_flags & RTF_PROBEMTU)) {
if (rt->rt_rmx.rmx_expire <= time_uptime) {
rt->rt_flags |= RTF_PROBEMTU;
} else {
ap->nextstop = lmin(ap->nextstop,
rt->rt_rmx.rmx_expire);
}
}
return 0;
}
#define MTUTIMO_DEFAULT (60*1)
static void
in6_mtutimo(void *rock)
{
CURVNET_SET_QUIET((struct vnet *) rock);
struct radix_node_head *rnh;
struct mtuex_arg arg;
struct timeval atv;
rnh = rt_tables_get_rnh(0, AF_INET6);
if (rnh == NULL) {
CURVNET_RESTORE();
return;
}
arg.rnh = rnh;
arg.nextstop = time_uptime + MTUTIMO_DEFAULT;
RADIX_NODE_HEAD_LOCK(rnh);
rnh->rnh_walktree(rnh, in6_mtuexpire, &arg);
RADIX_NODE_HEAD_UNLOCK(rnh);
atv.tv_usec = 0;
atv.tv_sec = arg.nextstop - time_uptime;
if (atv.tv_sec < 0) {
printf("invalid mtu expiration time on routing table\n");
arg.nextstop = time_uptime + 30; /* last resort */
atv.tv_sec = 30;
}
callout_reset(&V_rtq_mtutimer, tvtohz(&atv), in6_mtutimo, rock);
CURVNET_RESTORE();
}
/*
* Initialize our routing tree.
* XXX MRT When off == 0, we are being called from vfs_export.c
* so just set up their table and leave. (we know what the correct
* value should be so just use that).. FIX AFTER RELENG_7 is MFC'd
* see also comments in in_inithead() vfs_export.c and domain.h
*/
int
in6_inithead(void **head, int off)
{
struct radix_node_head *rnh;
if (!rn_inithead(head, offsetof(struct sockaddr_in6, sin6_addr) << 3))
return 0; /* See above */
if (off == 0) /* See above */
return 1; /* only do the rest for the real thing */
rnh = *head;
KASSERT(rnh == rt_tables_get_rnh(0, AF_INET6), ("rnh?"));
rnh->rnh_addaddr = in6_addroute;
rnh->rnh_matchaddr = in6_matroute;
callout_init(&V_rtq_timer6, CALLOUT_MPSAFE);
callout_init(&V_rtq_mtutimer, CALLOUT_MPSAFE);
in6_rtqtimo(curvnet); /* kick off timeout first time */
in6_mtutimo(curvnet); /* kick off timeout first time */
return 1;
}
#ifdef VIMAGE
int
in6_detachhead(void **head, int off)
{
callout_drain(&V_rtq_timer6);
callout_drain(&V_rtq_mtutimer);
return (1);
}
#endif
