[unix-history] / usr / src / sbin / routed / tables.c

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that this notice is preserved and that due credit is given
 * to the University of California at Berkeley. The name of the University
 * may not be used to endorse or promote products derived from this
 * software without specific prior written permission. This software
 * is provided ``as is'' without express or implied warranty.
 */

#ifndef lint
static char sccsid[] = "@(#)tables.c	5.11 (Berkeley) %G%";
#endif /* not lint */

/*
 * Routing Table Management Daemon
 */
#include "defs.h"
#include <sys/ioctl.h>
#include <errno.h>
#include <syslog.h>

#ifndef DEBUG
#define	DEBUG	0
#endif

int	install = !DEBUG;		/* if 1 call kernel */

/*
 * Lookup dst in the tables for an exact match.
 */
struct rt_entry *
rtlookup(dst)
	struct sockaddr *dst;
{
	register struct rt_entry *rt;
	register struct rthash *rh;
	register u_int hash;
	struct afhash h;
	int doinghost = 1;

	if (dst->sa_family >= af_max)
		return (0);
	(*afswitch[dst->sa_family].af_hash)(dst, &h);
	hash = h.afh_hosthash;
	rh = &hosthash[hash & ROUTEHASHMASK];
again:
	for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
		if (rt->rt_hash != hash)
			continue;
		if (equal(&rt->rt_dst, dst))
			return (rt);
	}
	if (doinghost) {
		doinghost = 0;
		hash = h.afh_nethash;
		rh = &nethash[hash & ROUTEHASHMASK];
		goto again;
	}
	return (0);
}

/*
 * Find a route to dst as the kernel would.
 */
struct rt_entry *
rtfind(dst)
	struct sockaddr *dst;
{
	register struct rt_entry *rt;
	register struct rthash *rh;
	register u_int hash;
	struct afhash h;
	int af = dst->sa_family;
	int doinghost = 1, (*match)();

	if (af >= af_max)
		return (0);
	(*afswitch[af].af_hash)(dst, &h);
	hash = h.afh_hosthash;
	rh = &hosthash[hash & ROUTEHASHMASK];

again:
	for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
		if (rt->rt_hash != hash)
			continue;
		if (doinghost) {
			if (equal(&rt->rt_dst, dst))
				return (rt);
		} else {
			if (rt->rt_dst.sa_family == af &&
			    (*match)(&rt->rt_dst, dst))
				return (rt);
		}
	}
	if (doinghost) {
		doinghost = 0;
		hash = h.afh_nethash;
		rh = &nethash[hash & ROUTEHASHMASK];
		match = afswitch[af].af_netmatch;
		goto again;
	}
	return (0);
}

rtadd(dst, gate, metric, state)
	struct sockaddr *dst, *gate;
	int metric, state;
{
	struct afhash h;
	register struct rt_entry *rt;
	struct rthash *rh;
	int af = dst->sa_family, flags;
	u_int hash;

	if (af >= af_max)
		return;
	(*afswitch[af].af_hash)(dst, &h);
	flags = (*afswitch[af].af_rtflags)(dst);
	/*
	 * Subnet flag isn't visible to kernel, move to state.	XXX
	 */
	if (flags & RTF_SUBNET) {
		state |= RTS_SUBNET;
		flags &= ~RTF_SUBNET;
	}
	if (flags & RTF_HOST) {
		hash = h.afh_hosthash;
		rh = &hosthash[hash & ROUTEHASHMASK];
	} else {
		hash = h.afh_nethash;
		rh = &nethash[hash & ROUTEHASHMASK];
	}
	rt = (struct rt_entry *)malloc(sizeof (*rt));
	if (rt == 0)
		return;
	rt->rt_hash = hash;
	rt->rt_dst = *dst;
	rt->rt_router = *gate;
	rt->rt_timer = 0;
	rt->rt_flags = RTF_UP | flags;
	rt->rt_state = state | RTS_CHANGED;
	rt->rt_ifp = if_ifwithdstaddr(&rt->rt_router);
	if (rt->rt_ifp == 0)
		rt->rt_ifp = if_ifwithnet(&rt->rt_router);
	if ((state & RTS_INTERFACE) == 0)
		rt->rt_flags |= RTF_GATEWAY;
	rt->rt_metric = metric;
	insque(rt, rh);
	TRACE_ACTION(ADD, rt);
	/*
	 * If the ioctl fails because the gateway is unreachable
	 * from this host, discard the entry.  This should only
	 * occur because of an incorrect entry in /etc/gateways.
	 */
	if (install && (rt->rt_state & (RTS_INTERNAL | RTS_EXTERNAL)) == 0 &&
	    ioctl(s, SIOCADDRT, (char *)&rt->rt_rt) < 0) {
		if (errno != EEXIST && gate->sa_family < af_max)
			syslog(LOG_ERR,
			"adding route to net/host %s through gateway %s: %m\n",
			   (*afswitch[dst->sa_family].af_format)(dst),
			   (*afswitch[gate->sa_family].af_format)(gate));
		perror("SIOCADDRT");
		if (errno == ENETUNREACH) {
			TRACE_ACTION(DELETE, rt);
			remque(rt);
			free((char *)rt);
		}
	}
}

rtchange(rt, gate, metric)
	struct rt_entry *rt;
	struct sockaddr *gate;
	short metric;
{
	int add = 0, delete = 0, metricchanged = 0;
	struct rtentry oldroute;

	if ((rt->rt_state & RTS_INTERNAL) == 0) {
		/*
		 * If changing to different router, we need to add
		 * new route and delete old one if in the kernel.
		 * If the router is the same, we need to delete
		 * the route if has become unreachable, or re-add
		 * it if it had been unreachable.
		 */
		if (!equal(&rt->rt_router, gate)) {
			add++;
			if (rt->rt_metric != HOPCNT_INFINITY)
				delete++;
		} else if (metric == HOPCNT_INFINITY)
			delete++;
		else if (rt->rt_metric == HOPCNT_INFINITY)
			add++;
	}
	if (metric != rt->rt_metric)
		metricchanged++;
	if (delete || metricchanged)
		TRACE_ACTION(CHANGE FROM, rt);
	if ((rt->rt_state & RTS_INTERFACE) && delete) {
		rt->rt_state &= ~RTS_INTERFACE;
		if (add)
			rt->rt_flags |= RTF_GATEWAY;
		if (metric > rt->rt_metric && delete &&
		    (rt->rt_state & RTS_INTERNAL) == 0)
			syslog(LOG_ERR,
				"changing route from interface %s (timed out)",
				rt->rt_ifp->int_name);
	}
	if (delete)
		oldroute = rt->rt_rt;
	if (add) {
		rt->rt_router = *gate;
		rt->rt_ifp = if_ifwithdstaddr(&rt->rt_router);
		if (rt->rt_ifp == 0)
			rt->rt_ifp = if_ifwithnet(&rt->rt_router);
	}
	rt->rt_metric = metric;
	rt->rt_state |= RTS_CHANGED;
	if (add || metricchanged)
		TRACE_ACTION(CHANGE TO, rt);
	if (add && install)
		if (ioctl(s, SIOCADDRT, (char *)&rt->rt_rt) < 0)
			perror("SIOCADDRT");
	if (delete && install)
		if (ioctl(s, SIOCDELRT, (char *)&oldroute) < 0)
			perror("SIOCDELRT");
}

rtdelete(rt)
	struct rt_entry *rt;
{

	if ((rt->rt_state & (RTS_INTERFACE|RTS_INTERNAL)) == RTS_INTERFACE)
		syslog(LOG_ERR, "deleting route to interface %s (timed out)",
			rt->rt_ifp->int_name);
	TRACE_ACTION(DELETE, rt);
	if (install && (rt->rt_state & (RTS_INTERNAL | RTS_EXTERNAL)) == 0 &&
	    ioctl(s, SIOCDELRT, (char *)&rt->rt_rt))
		perror("SIOCDELRT");
	remque(rt);
	free((char *)rt);
}

rtdeleteall(s)
	int s;
{
	register struct rthash *rh;
	register struct rt_entry *rt;
	struct rthash *base = hosthash;
	int doinghost = 1;

again:
	for (rh = base; rh < &base[ROUTEHASHSIZ]; rh++) {
		rt = rh->rt_forw;
		for (; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
			if (rt->rt_state & RTS_INTERFACE)
				continue;
			TRACE_ACTION(DELETE, rt);
			if ((rt->rt_state & (RTS_INTERNAL|RTS_EXTERNAL)) == 0 &&
			    ioctl(s, SIOCDELRT, (char *)&rt->rt_rt))
				perror("SIOCDELRT");
		}
	}
	if (doinghost) {
		doinghost = 0;
		base = nethash;
		goto again;
	}
	hup(s);
}

/*
 * If we have an interface to the wide, wide world,
 * add an entry for an Internet default route (wildcard) to the internal
 * tables and advertise it.  This route is not added to the kernel routes,
 * but this entry prevents us from listening to other people's defaults
 * and installing them in the kernel here.
 */
rtdefault()
{
	extern struct sockaddr inet_default;

	rtadd(&inet_default, &inet_default, 0,
		RTS_CHANGED | RTS_PASSIVE | RTS_INTERNAL);
}

rtinit()
{
	register struct rthash *rh;

	for (rh = nethash; rh < &nethash[ROUTEHASHSIZ]; rh++)
		rh->rt_forw = rh->rt_back = (struct rt_entry *)rh;
	for (rh = hosthash; rh < &hosthash[ROUTEHASHSIZ]; rh++)
		rh->rt_forw = rh->rt_back = (struct rt_entry *)rh;
}
Commit	Line	Data
5ff67f98 DF	1	/*
5ff67f98 DF	2	* Copyright (c) 1983 Regents of the University of California.
0eb85d71 KB	3	* All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms are permitted
	6	* provided that this notice is preserved and that due credit is given
	7	* to the University of California at Berkeley. The name of the University
	8	* may not be used to endorse or promote products derived from this
	9	* software without specific prior written permission. This software
	10	* is provided ``as is'' without express or implied warranty.
5ff67f98 DF	11	*/
5ff67f98 DF	12
b9b7b06a	13	#ifndef lint
0eb85d71 KB	14	static char sccsid[] = "@(#)tables.c 5.11 (Berkeley) %G%";
0eb85d71 KB	15	#endif /* not lint */
b9b7b06a SL	16
	17	/*
	18	* Routing Table Management Daemon
	19	*/
7fe7fe74	20	#include "defs.h"
b9b7b06a SL	21	#include <sys/ioctl.h>
b9b7b06a SL	22	#include <errno.h>
69b7ef61	23	#include <syslog.h>
b9b7b06a SL	24
	25	#ifndef DEBUG
	26	#define DEBUG 0
	27	#endif
	28
	29	int install = !DEBUG; /* if 1 call kernel */
	30
	31	/*
	32	* Lookup dst in the tables for an exact match.
	33	*/
	34	struct rt_entry *
	35	rtlookup(dst)
	36	struct sockaddr *dst;
	37	{
	38	register struct rt_entry *rt;
	39	register struct rthash *rh;
d5568f13	40	register u_int hash;
b9b7b06a SL	41	struct afhash h;
	42	int doinghost = 1;
	43
17fe297f	44	if (dst->sa_family >= af_max)
b9b7b06a SL	45	return (0);
	46	(*afswitch[dst->sa_family].af_hash)(dst, &h);
	47	hash = h.afh_hosthash;
49139b80	48	rh = &hosthash[hash & ROUTEHASHMASK];
b9b7b06a SL	49	again:
	50	for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
	51	if (rt->rt_hash != hash)
	52	continue;
	53	if (equal(&rt->rt_dst, dst))
	54	return (rt);
	55	}
	56	if (doinghost) {
	57	doinghost = 0;
	58	hash = h.afh_nethash;
49139b80	59	rh = &nethash[hash & ROUTEHASHMASK];
b9b7b06a SL	60	goto again;
	61	}
	62	return (0);
	63	}
	64
	65	/*
	66	* Find a route to dst as the kernel would.
	67	*/
	68	struct rt_entry *
	69	rtfind(dst)
	70	struct sockaddr *dst;
	71	{
	72	register struct rt_entry *rt;
	73	register struct rthash *rh;
d5568f13	74	register u_int hash;
b9b7b06a SL	75	struct afhash h;
	76	int af = dst->sa_family;
	77	int doinghost = 1, (*match)();
	78
17fe297f	79	if (af >= af_max)
b9b7b06a SL	80	return (0);
	81	(*afswitch[af].af_hash)(dst, &h);
	82	hash = h.afh_hosthash;
49139b80	83	rh = &hosthash[hash & ROUTEHASHMASK];
b9b7b06a SL	84
	85	again:
	86	for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
	87	if (rt->rt_hash != hash)
	88	continue;
	89	if (doinghost) {
	90	if (equal(&rt->rt_dst, dst))
	91	return (rt);
	92	} else {
	93	if (rt->rt_dst.sa_family == af &&
	94	(*match)(&rt->rt_dst, dst))
	95	return (rt);
	96	}
	97	}
	98	if (doinghost) {
	99	doinghost = 0;
	100	hash = h.afh_nethash;
49139b80	101	rh = &nethash[hash & ROUTEHASHMASK];
b9b7b06a SL	102	match = afswitch[af].af_netmatch;
	103	goto again;
	104	}
	105	return (0);
	106	}
	107
	108	rtadd(dst, gate, metric, state)
	109	struct sockaddr dst, gate;
	110	int metric, state;
	111	{
	112	struct afhash h;
	113	register struct rt_entry *rt;
	114	struct rthash *rh;
7892134c	115	int af = dst->sa_family, flags;
d5568f13	116	u_int hash;
b9b7b06a	117
17fe297f	118	if (af >= af_max)
b9b7b06a SL	119	return;
b9b7b06a SL	120	(*afswitch[af].af_hash)(dst, &h);
4fad5a6e MK	121	flags = (*afswitch[af].af_rtflags)(dst);
	122	/*
	123	* Subnet flag isn't visible to kernel, move to state. XXX
	124	*/
	125	if (flags & RTF_SUBNET) {
	126	state \|= RTS_SUBNET;
	127	flags &= ~RTF_SUBNET;
	128	}
b9b7b06a SL	129	if (flags & RTF_HOST) {
b9b7b06a SL	130	hash = h.afh_hosthash;
49139b80	131	rh = &hosthash[hash & ROUTEHASHMASK];
b9b7b06a SL	132	} else {
b9b7b06a SL	133	hash = h.afh_nethash;
49139b80	134	rh = &nethash[hash & ROUTEHASHMASK];
b9b7b06a SL	135	}
	136	rt = (struct rt_entry )malloc(sizeof (rt));
	137	if (rt == 0)
	138	return;
	139	rt->rt_hash = hash;
	140	rt->rt_dst = *dst;
	141	rt->rt_router = *gate;
b9b7b06a SL	142	rt->rt_timer = 0;
	143	rt->rt_flags = RTF_UP \| flags;
	144	rt->rt_state = state \| RTS_CHANGED;
4fad5a6e MK	145	rt->rt_ifp = if_ifwithdstaddr(&rt->rt_router);
	146	if (rt->rt_ifp == 0)
	147	rt->rt_ifp = if_ifwithnet(&rt->rt_router);
88709531	148	if ((state & RTS_INTERFACE) == 0)
b9b7b06a	149	rt->rt_flags \|= RTF_GATEWAY;
7892134c	150	rt->rt_metric = metric;
b9b7b06a SL	151	insque(rt, rh);
b9b7b06a SL	152	TRACE_ACTION(ADD, rt);
a8d9e287 SL	153	/*
	154	* If the ioctl fails because the gateway is unreachable
	155	* from this host, discard the entry. This should only
	156	* occur because of an incorrect entry in /etc/gateways.
	157	*/
4fad5a6e MK	158	if (install && (rt->rt_state & (RTS_INTERNAL \| RTS_EXTERNAL)) == 0 &&
4fad5a6e MK	159	ioctl(s, SIOCADDRT, (char *)&rt->rt_rt) < 0) {
7892134c	160	if (errno != EEXIST && gate->sa_family < af_max)
c766cf31 MK	161	syslog(LOG_ERR,
	162	"adding route to net/host %s through gateway %s: %m\n",
	163	(*afswitch[dst->sa_family].af_format)(dst),
	164	(*afswitch[gate->sa_family].af_format)(gate));
b9b7b06a	165	perror("SIOCADDRT");
a8d9e287 SL	166	if (errno == ENETUNREACH) {
	167	TRACE_ACTION(DELETE, rt);
	168	remque(rt);
	169	free((char *)rt);
	170	}
	171	}
b9b7b06a SL	172	}
	173
	174	rtchange(rt, gate, metric)
	175	struct rt_entry *rt;
	176	struct sockaddr *gate;
	177	short metric;
	178	{
7892134c	179	int add = 0, delete = 0, metricchanged = 0;
b9b7b06a SL	180	struct rtentry oldroute;
b9b7b06a SL	181
7892134c MK	182	if ((rt->rt_state & RTS_INTERNAL) == 0) {
	183	/*
	184	* If changing to different router, we need to add
	185	* new route and delete old one if in the kernel.
	186	* If the router is the same, we need to delete
	187	* the route if has become unreachable, or re-add
	188	* it if it had been unreachable.
	189	*/
	190	if (!equal(&rt->rt_router, gate)) {
	191	add++;
	192	if (rt->rt_metric != HOPCNT_INFINITY)
	193	delete++;
	194	} else if (metric == HOPCNT_INFINITY)
eb39c032	195	delete++;
7892134c MK	196	else if (rt->rt_metric == HOPCNT_INFINITY)
7892134c MK	197	add++;
eb39c032	198	}
7892134c MK	199	if (metric != rt->rt_metric)
	200	metricchanged++;
	201	if (delete \|\| metricchanged)
b7e4f8be	202	TRACE_ACTION(CHANGE FROM, rt);
7892134c MK	203	if ((rt->rt_state & RTS_INTERFACE) && delete) {
	204	rt->rt_state &= ~RTS_INTERFACE;
	205	if (add)
88709531	206	rt->rt_flags \|= RTF_GATEWAY;
7892134c MK	207	if (metric > rt->rt_metric && delete &&
7892134c MK	208	(rt->rt_state & RTS_INTERNAL) == 0)
aa7d0b61 MK	209	syslog(LOG_ERR,
	210	"changing route from interface %s (timed out)",
	211	rt->rt_ifp->int_name);
b9b7b06a	212	}
7892134c MK	213	if (delete)
	214	oldroute = rt->rt_rt;
	215	if (add) {
	216	rt->rt_router = *gate;
	217	rt->rt_ifp = if_ifwithdstaddr(&rt->rt_router);
	218	if (rt->rt_ifp == 0)
	219	rt->rt_ifp = if_ifwithnet(&rt->rt_router);
	220	}
	221	rt->rt_metric = metric;
	222	rt->rt_state \|= RTS_CHANGED;
	223	if (add \|\| metricchanged)
	224	TRACE_ACTION(CHANGE TO, rt);
	225	if (add && install)
b7e4f8be MK	226	if (ioctl(s, SIOCADDRT, (char *)&rt->rt_rt) < 0)
b7e4f8be MK	227	perror("SIOCADDRT");
7892134c	228	if (delete && install)
b7e4f8be MK	229	if (ioctl(s, SIOCDELRT, (char *)&oldroute) < 0)
b7e4f8be MK	230	perror("SIOCDELRT");
b9b7b06a SL	231	}
	232
	233	rtdelete(rt)
	234	struct rt_entry *rt;
	235	{
a8d9e287	236
7892134c	237	if ((rt->rt_state & (RTS_INTERFACE\|RTS_INTERNAL)) == RTS_INTERFACE)
69b7ef61 MK	238	syslog(LOG_ERR, "deleting route to interface %s (timed out)",
69b7ef61 MK	239	rt->rt_ifp->int_name);
b9b7b06a	240	TRACE_ACTION(DELETE, rt);
b1d43e6c	241	if (install && (rt->rt_state & (RTS_INTERNAL \| RTS_EXTERNAL)) == 0 &&
4fad5a6e	242	ioctl(s, SIOCDELRT, (char *)&rt->rt_rt))
b9b7b06a SL	243	perror("SIOCDELRT");
	244	remque(rt);
	245	free((char *)rt);
	246	}
	247
7892134c MK	248	rtdeleteall(s)
	249	int s;
	250	{
	251	register struct rthash *rh;
	252	register struct rt_entry *rt;
	253	struct rthash *base = hosthash;
	254	int doinghost = 1;
	255
	256	again:
	257	for (rh = base; rh < &base[ROUTEHASHSIZ]; rh++) {
	258	rt = rh->rt_forw;
	259	for (; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
	260	if (rt->rt_state & RTS_INTERFACE)
	261	continue;
	262	TRACE_ACTION(DELETE, rt);
	263	if ((rt->rt_state & (RTS_INTERNAL\|RTS_EXTERNAL)) == 0 &&
	264	ioctl(s, SIOCDELRT, (char *)&rt->rt_rt))
	265	perror("SIOCDELRT");
	266	}
	267	}
	268	if (doinghost) {
	269	doinghost = 0;
	270	base = nethash;
	271	goto again;
	272	}
	273	hup(s);
	274	}
	275
ad34083f MK	276	/*
	277	* If we have an interface to the wide, wide world,
	278	* add an entry for an Internet default route (wildcard) to the internal
	279	* tables and advertise it. This route is not added to the kernel routes,
	280	* but this entry prevents us from listening to other people's defaults
	281	* and installing them in the kernel here.
	282	*/
	283	rtdefault()
	284	{
ad34083f MK	285	extern struct sockaddr inet_default;
ad34083f MK	286
4fad5a6e MK	287	rtadd(&inet_default, &inet_default, 0,
4fad5a6e MK	288	RTS_CHANGED \| RTS_PASSIVE \| RTS_INTERNAL);
ad34083f MK	289	}
ad34083f MK	290
b9b7b06a SL	291	rtinit()
	292	{
	293	register struct rthash *rh;
	294
	295	for (rh = nethash; rh < &nethash[ROUTEHASHSIZ]; rh++)
	296	rh->rt_forw = rh->rt_back = (struct rt_entry *)rh;
	297	for (rh = hosthash; rh < &hosthash[ROUTEHASHSIZ]; rh++)
	298	rh->rt_forw = rh->rt_back = (struct rt_entry *)rh;
	299	}