/*- * 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 __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include 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); #ifdef VIMAGE_GLOBALS static int rtq_reallyold6; static int rtq_minreallyold6; static int rtq_toomany6; #endif SYSCTL_V_INT(V_NET, vnet_inet6, _net_inet6_ip6, IPV6CTL_RTEXPIRE, rtexpire, CTLFLAG_RW, rtq_reallyold6 , 0, ""); SYSCTL_V_INT(V_NET, vnet_inet6, _net_inet6_ip6, IPV6CTL_RTMINEXPIRE, rtminexpire, CTLFLAG_RW, rtq_minreallyold6 , 0, ""); SYSCTL_V_INT(V_NET, vnet_inet6, _net_inet6_ip6, IPV6CTL_RTMAXCACHE, rtmaxcache, CTLFLAG_RW, 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) { INIT_VNET_INET6(curvnet); 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 */ #ifdef VIMAGE_GLOBALS static int rtq_timeout6; static struct callout rtq_timer6; #endif static void in6_rtqtimo(void *rock) { CURVNET_SET_QUIET((struct vnet *) rock); INIT_VNET_INET6(curvnet); 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; }; #ifdef VIMAGE_GLOBALS static struct callout rtq_mtutimer; #endif 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); INIT_VNET_INET6(curvnet); 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) { INIT_VNET_INET6(curvnet); 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 */ V_rtq_reallyold6 = 60*60; /* one hour is ``really old'' */ V_rtq_minreallyold6 = 10; /* never automatically crank down to less */ V_rtq_toomany6 = 128; /* 128 cached routes is ``too many'' */ V_rtq_timeout6 = RTQ_TIMEOUT; 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) { INIT_VNET_INET6(curvnet); callout_drain(&V_rtq_timer6); callout_drain(&V_rtq_mtutimer); return (1); } #endif