📄 route.c
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//==========================================================================
//
// sys/net/route.c
//
//
//
//==========================================================================
//####BSDCOPYRIGHTBEGIN####
//
// -------------------------------------------
//
// Portions of this software may have been derived from OpenBSD or other sources,
// and are covered by the appropriate copyright disclaimers included herein.
//
// -------------------------------------------
//
//####BSDCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s): gthomas
// Contributors: gthomas
// Date: 2000-01-10
// Purpose:
// Description:
//
//
//####DESCRIPTIONEND####
//
//==========================================================================
/* $OpenBSD: route.c,v 1.16 1999/12/08 06:50:18 itojun Exp $ */
/* $NetBSD: route.c,v 1.14 1996/02/13 22:00:46 christos Exp $ */
/*
* 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.
*/
/*
* Copyright (c) 1980, 1986, 1991, 1993
* The Regents of the University of California. 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#)route.c 8.2 (Berkeley) 11/15/93
*/
/*
%%% portions-copyright-nrl-95
Portions of this software are Copyright 1995-1998 by Randall Atkinson,
Ronald Lee, Daniel McDonald, Bao Phan, and Chris Winters. All Rights
Reserved. All rights under this copyright have been assigned to the US
Naval Research Laboratory (NRL). The NRL Copyright Notice and License
Agreement Version 1.1 (January 17, 1995) applies to these portions of the
software.
You should have received a copy of the license with this software. If you
didn't get a copy, you may request one from <license@ipv6.nrl.navy.mil>.
*/
#include <sys/param.h>
#ifdef __ECOS
struct proc {
int __unused;
};
#else
#include <sys/systm.h>
#include <sys/proc.h>
#endif
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/route.h>
#include <net/raw_cb.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#ifdef NS
#include <netns/ns.h>
#endif
#ifdef IPSEC
#include <netinet/ip_ipsp.h>
extern struct ifnet encif;
#endif
#define SA(p) ((struct sockaddr *)(p))
int rttrash; /* routes not in table but not freed */
struct sockaddr wildcard; /* zero valued cookie for wildcard searches */
static int okaytoclone __P((u_int, int));
#ifdef IPSEC
static struct ifaddr *
encap_findgwifa(struct sockaddr *gw)
{
return encif.if_addrlist.tqh_first;
}
#endif
void
rtable_init(table)
void **table;
{
struct domain *dom;
for (dom = domains; dom; dom = dom->dom_next)
if (dom->dom_rtattach)
dom->dom_rtattach(&table[dom->dom_family],
dom->dom_rtoffset);
}
void
route_init()
{
rn_init(); /* initialize all zeroes, all ones, mask table */
rtable_init((void **)rt_tables);
}
// FIXME: This function is only here because BOOTP fails on a second interface.
// This failure is due to the fact that a route to 0.0.0.0 seems to be
// incredibly sticky, i.e. can't be deleted. BOOTP uses this to
// achieve a generic broadcast. Sadly it seems that BOOTP servers will
// only work this way, thus the hack.
//
// This version enumerates all routes and deletes them - this leaks less
// store than the previous version.
static int
rt_reinit_rtdelete( struct radix_node *rn, void *vifp )
{
struct rtentry *rt = (struct rtentry *)rn;
rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway, rt_mask(rt),
0, NULL);
return (0);
}
void
cyg_route_reinit(void)
{
int i;
for (i = 0; i < AF_MAX+1; i++) {
struct radix_node_head *rnh;
rnh = rt_tables[i];
if (rnh) {
(*rnh->rnh_walktree)(rnh, rt_reinit_rtdelete, NULL);
}
}
}
void
rtalloc_noclone(ro, howstrict)
register struct route *ro;
int howstrict;
{
if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP))
return; /* XXX */
ro->ro_rt = rtalloc2(&ro->ro_dst, 1, howstrict);
}
static int
okaytoclone(flags, howstrict)
u_int flags;
int howstrict;
{
if (howstrict == ALL_CLONING)
return 1;
if (howstrict == ONNET_CLONING && !(flags & (RTF_GATEWAY|RTF_TUNNEL)))
return 1;
return 0;
}
struct rtentry *
rtalloc2(dst, report,howstrict)
register struct sockaddr *dst;
int report,howstrict;
{
register struct radix_node_head *rnh = rt_tables[dst->sa_family];
register struct rtentry *rt;
register struct radix_node *rn;
struct rtentry *newrt = 0;
struct rt_addrinfo info;
int s = splnet(), err = 0, msgtype = RTM_MISS;
if (rnh && (rn = rnh->rnh_matchaddr((caddr_t)dst, rnh)) &&
((rn->rn_flags & RNF_ROOT) == 0)) {
newrt = rt = (struct rtentry *)rn;
if (report && (rt->rt_flags & RTF_CLONING) &&
okaytoclone(rt->rt_flags, howstrict)) {
err = rtrequest(RTM_RESOLVE, dst, SA(0), SA(0), 0,
&newrt);
if (err) {
newrt = rt;
rt->rt_refcnt++;
goto miss;
}
if ((rt = newrt) && (rt->rt_flags & RTF_XRESOLVE)) {
msgtype = RTM_RESOLVE;
goto miss;
}
} else
rt->rt_refcnt++;
} else {
rtstat.rts_unreach++;
miss: if (report) {
bzero((caddr_t)&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
rt_missmsg(msgtype, &info, 0, err);
}
}
splx(s);
return (newrt);
}
/*
* Packet routing routines.
*/
void
rtalloc(ro)
register struct route *ro;
{
if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP))
return; /* XXX */
ro->ro_rt = rtalloc1(&ro->ro_dst, 1);
}
struct rtentry *
rtalloc1(dst, report)
register struct sockaddr *dst;
int report;
{
register struct radix_node_head *rnh = rt_tables[dst->sa_family];
register struct rtentry *rt;
register struct radix_node *rn;
struct rtentry *newrt = 0;
struct rt_addrinfo info;
int s = splsoftnet(), err = 0, msgtype = RTM_MISS;
if (rnh && (rn = rnh->rnh_matchaddr((caddr_t)dst, rnh)) &&
((rn->rn_flags & RNF_ROOT) == 0)) {
newrt = rt = (struct rtentry *)rn;
if (report && (rt->rt_flags & RTF_CLONING)) {
err = rtrequest(RTM_RESOLVE, dst, SA(NULL),
SA(NULL), 0, &newrt);
if (err) {
newrt = rt;
rt->rt_refcnt++;
goto miss;
}
if ((rt = newrt) && (rt->rt_flags & RTF_XRESOLVE)) {
msgtype = RTM_RESOLVE;
goto miss;
}
} else
rt->rt_refcnt++;
} else {
if (dst->sa_family != PF_KEY)
rtstat.rts_unreach++;
/*
* IP encapsulation does lots of lookups where we don't need nor want
* the RTM_MISSes that would be generated. It causes RTM_MISS storms
* sent upward breaking user-level routing queries.
*/
miss: if (report && dst->sa_family != PF_KEY) {
bzero((caddr_t)&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
rt_missmsg(msgtype, &info, 0, err);
}
}
splx(s);
return (newrt);
}
void
rtfree(rt)
register struct rtentry *rt;
{
register struct ifaddr *ifa;
if (rt == NULL)
panic("rtfree");
rt->rt_refcnt--;
if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_UP) == 0) {
if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT))
panic ("rtfree 2");
rttrash--;
if (rt->rt_refcnt < 0) {
#ifdef __ECOS
diag_printf("rtfree: %x not freed (neg refs)\n", rt);
#else
printf("rtfree: %x not freed (neg refs)\n", rt);
#endif
return;
}
rt_timer_remove_all(rt);
ifa = rt->rt_ifa;
if (ifa)
IFAFREE(ifa);
Free(rt_key(rt));
Free(rt);
}
}
void
ifafree(ifa)
register struct ifaddr *ifa;
{
if (ifa == NULL)
panic("ifafree");
if (ifa->ifa_refcnt == 0)
free(ifa, M_IFADDR);
else
ifa->ifa_refcnt--;
}
/*
* Force a routing table entry to the specified
* destination to go through the given gateway.
* Normally called as a result of a routing redirect
* message from the network layer.
*
* N.B.: must be called at splsoftnet
*/
void
rtredirect(dst, gateway, netmask, flags, src, rtp)
struct sockaddr *dst, *gateway, *netmask, *src;
int flags;
struct rtentry **rtp;
{
register struct rtentry *rt;
int error = 0;
u_int32_t *stat = NULL;
struct rt_addrinfo info;
struct ifaddr *ifa;
/* verify the gateway is directly reachable */
if ((ifa = ifa_ifwithnet(gateway)) == NULL) {
error = ENETUNREACH;
goto out;
}
rt = rtalloc1(dst, 0);
/*
* If the redirect isn't from our current router for this dst,
* it's either old or wrong. If it redirects us to ourselves,
* we have a routing loop, perhaps as a result of an interface
* going down recently.
*/
#define equal(a1, a2) (bcmp((caddr_t)(a1), (caddr_t)(a2), (a1)->sa_len) == 0)
if (!(flags & RTF_DONE) && rt &&
(!equal(src, rt->rt_gateway) || rt->rt_ifa != ifa))
error = EINVAL;
else if (ifa_ifwithaddr(gateway) != NULL)
error = EHOSTUNREACH;
if (error)
goto done;
/*
* Create a new entry if we just got back a wildcard entry
* or the the lookup failed. This is necessary for hosts
* which use routing redirects generated by smart gateways
* to dynamically build the routing tables.
*/
if ((rt == NULL) || (rt_mask(rt) && rt_mask(rt)->sa_len < 2))
goto create;
/*
* Don't listen to the redirect if it's
* for a route to an interface.
*/
if (rt->rt_flags & RTF_GATEWAY) {
if (((rt->rt_flags & RTF_HOST) == 0) && (flags & RTF_HOST)) {
/*
* Changing from route to net => route to host.
* Create new route, rather than smashing route to net.
*/
create:
flags |= RTF_GATEWAY | RTF_DYNAMIC;
error = rtrequest((int)RTM_ADD, dst, gateway,
netmask, flags,
(struct rtentry **)0);
stat = &rtstat.rts_dynamic;
} else {
/*
* Smash the current notion of the gateway to
* this destination. Should check about netmask!!!
*/
rt->rt_flags |= RTF_MODIFIED;
flags |= RTF_MODIFIED;
stat = &rtstat.rts_newgateway;
rt_setgate(rt, rt_key(rt), gateway);
}
} else
error = EHOSTUNREACH;
done:
if (rt) {
if (rtp && !error)
*rtp = rt;
else
rtfree(rt);
}
out:
if (error)
rtstat.rts_badredirect++;
else if (stat != NULL)
(*stat)++;
bzero((caddr_t)&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_info[RTAX_NETMASK] = netmask;
info.rti_info[RTAX_AUTHOR] = src;
rt_missmsg(RTM_REDIRECT, &info, flags, error);
}
/*
* Routing table ioctl interface.
*/
int
rtioctl(req, data, p)
u_long req;
caddr_t data;
struct proc *p;
{
#ifdef __ECOS
struct ecos_rtentry *rt;
int res;
switch (req) {
case SIOCADDRT:
rt = (struct ecos_rtentry *)data;
res = rtrequest(RTM_ADD,
&rt->rt_dst,
&rt->rt_gateway,
&rt->rt_genmask,
rt->rt_flags,
NULL);
return (res);
case SIOCDELRT:
rt = (struct ecos_rtentry *)data;
res = rtrequest(RTM_DELETE,
&rt->rt_dst,
&rt->rt_gateway,
&rt->rt_genmask,
rt->rt_flags,
NULL);
return (res);
default:
return (EOPNOTSUPP);
}
#else
return (EOPNOTSUPP);
#endif
}
struct ifaddr *
ifa_ifwithroute(flags, dst, gateway)
int flags;
struct sockaddr *dst, *gateway;
{
register struct ifaddr *ifa;
#ifdef IPSEC
/*
* If the destination is a PF_KEY address, we'll look
* for the existence of a encap interface number or address
* in the options list of the gateway. By default, we'll return
* enc0.
*/
if (dst && (dst->sa_family == PF_KEY))
return encap_findgwifa(gateway);
#endif
if ((flags & RTF_GATEWAY) == 0) {
/*
* If we are adding a route to an interface,
* and the interface is a pt to pt link
* we should search for the destination
* as our clue to the interface. Otherwise
* we can use the local address.
*/
ifa = NULL;
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