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

#ifndef lint
static char sccsid[] = "@(#)input.c	4.10 (Berkeley) %G%";
#endif

/*
 * Routing Table Management Daemon
 */
#include "defs.h"

/*
 * Process a newly received packet.
 */
rip_input(from, size)
	struct sockaddr *from;
	int size;
{
	struct rt_entry *rt;
	struct netinfo *n;
	struct interface *ifp;
	int newsize;
	struct afswitch *afp;

	ifp = 0;
	TRACE_INPUT(ifp, from, size);
	if (from->sa_family >= AF_MAX)
		return;
	afp = &afswitch[from->sa_family];
	switch (msg->rip_cmd) {

	case RIPCMD_REQUEST:
		newsize = 0;
		size -= 4 * sizeof (char);
		n = msg->rip_nets;
		while (size > 0) {
			if (size < sizeof (struct netinfo))
				break;
			size -= sizeof (struct netinfo);

			if (msg->rip_vers > 0) {
				n->rip_dst.sa_family =
					ntohs(n->rip_dst.sa_family);
				n->rip_metric = ntohl(n->rip_metric);
			}
			/* 
			 * A single entry with sa_family == AF_UNSPEC and
			 * metric ``infinity'' means ``all routes''.
			 */
			if (n->rip_dst.sa_family == AF_UNSPEC &&
			    n->rip_metric == HOPCNT_INFINITY && size == 0) {
				supply(from, 0, ifp);
				return;
			}
			rt = rtlookup(&n->rip_dst);
			n->rip_metric = rt == 0 ? HOPCNT_INFINITY :
				min(rt->rt_metric+1, HOPCNT_INFINITY);
			if (msg->rip_vers > 0) {
				n->rip_dst.sa_family =
					htons(n->rip_dst.sa_family);
				n->rip_metric = htonl(n->rip_metric);
			}
			n++, newsize += sizeof (struct netinfo);
		}
		if (newsize > 0) {
			msg->rip_cmd = RIPCMD_RESPONSE;
			newsize += sizeof (int);
			(*afp->af_output)(s, 0, from, newsize);
		}
		return;

	case RIPCMD_TRACEON:
	case RIPCMD_TRACEOFF:
		/* verify message came from a privileged port */
		if ((*afp->af_portcheck)(from) == 0)
			return;
		packet[size] = '\0';
		if (msg->rip_cmd == RIPCMD_TRACEON)
			traceon(msg->rip_tracefile);
		else
			traceoff();
		return;

	case RIPCMD_RESPONSE:
		/* verify message came from a router */
		if ((*afp->af_portmatch)(from) == 0)
			return;
		(*afp->af_canon)(from);
		/* are we talking to ourselves? */
		ifp = if_ifwithaddr(from);
		if (ifp) {
			rt = rtfind(from);
			if (rt == 0 || (rt->rt_state & RTS_INTERFACE) == 0)
				addrouteforif(ifp);
			else
				rt->rt_timer = 0;
			return;
		}
		/*
		 * Update timer for interface on which the packet arrived.
		 * If from other end of a point-to-point link that isn't
		 * in the routing tables, (re-)add the route.
		 */
		if ((rt = rtfind(from)) && (rt->rt_state & RTS_INTERFACE))
			rt->rt_timer = 0;
		else if (ifp = if_ifwithdstaddr(from))
			addrouteforif(ifp);
		size -= 4 * sizeof (char);
		n = msg->rip_nets;
		for (; size > 0; size -= sizeof (struct netinfo), n++) {
			if (size < sizeof (struct netinfo))
				break;
			if (msg->rip_vers > 0) {
				n->rip_dst.sa_family =
					ntohs(n->rip_dst.sa_family);
				n->rip_metric = ntohl(n->rip_metric);
			}
			if ((unsigned) n->rip_metric >= HOPCNT_INFINITY)
				continue;
			if (n->rip_dst.sa_family >= AF_MAX)
				continue;
			afp = &afswitch[n->rip_dst.sa_family];
			if (((*afp->af_checkhost)(&n->rip_dst)) == 0)
				continue;
			rt = rtlookup(&n->rip_dst);
			if (rt == 0) {
				rtadd(&n->rip_dst, from, n->rip_metric, 0);
				continue;
			}

			/*
			 * Update if from gateway and different,
			 * shorter, or getting stale and equivalent.
			 */
			if ((equal(from, &rt->rt_router) &&
			    n->rip_metric != rt->rt_metric ) ||
			    (unsigned) (n->rip_metric) < rt->rt_metric ||
			    (rt->rt_timer > (EXPIRE_TIME/2) &&
			    rt->rt_metric == n->rip_metric)) {
				rtchange(rt, from, n->rip_metric);
				rt->rt_timer = 0;
			}
		}
		return;
	}
}
Commit	Line	Data
2e74322d	1	#ifndef lint
f1e15e15	2	static char sccsid[] = "@(#)input.c 4.10 (Berkeley) %G%";
2e74322d SL	3	#endif
	4
	5	/*
	6	* Routing Table Management Daemon
	7	*/
7fe7fe74	8	#include "defs.h"
2e74322d SL	9
	10	/*
	11	* Process a newly received packet.
	12	*/
	13	rip_input(from, size)
	14	struct sockaddr *from;
	15	int size;
	16	{
	17	struct rt_entry *rt;
	18	struct netinfo *n;
	19	struct interface *ifp;
	20	int newsize;
	21	struct afswitch *afp;
	22
	23	ifp = 0;
	24	TRACE_INPUT(ifp, from, size);
	25	if (from->sa_family >= AF_MAX)
	26	return;
	27	afp = &afswitch[from->sa_family];
	28	switch (msg->rip_cmd) {
	29
	30	case RIPCMD_REQUEST:
	31	newsize = 0;
	32	size -= 4 * sizeof (char);
	33	n = msg->rip_nets;
	34	while (size > 0) {
	35	if (size < sizeof (struct netinfo))
	36	break;
	37	size -= sizeof (struct netinfo);
	38
55d340a4 SL	39	if (msg->rip_vers > 0) {
	40	n->rip_dst.sa_family =
	41	ntohs(n->rip_dst.sa_family);
	42	n->rip_metric = ntohl(n->rip_metric);
	43	}
2e74322d SL	44	/*
	45	* A single entry with sa_family == AF_UNSPEC and
	46	* metric ``infinity'' means ``all routes''.
	47	*/
	48	if (n->rip_dst.sa_family == AF_UNSPEC &&
	49	n->rip_metric == HOPCNT_INFINITY && size == 0) {
	50	supply(from, 0, ifp);
	51	return;
	52	}
	53	rt = rtlookup(&n->rip_dst);
	54	n->rip_metric = rt == 0 ? HOPCNT_INFINITY :
	55	min(rt->rt_metric+1, HOPCNT_INFINITY);
55d340a4 SL	56	if (msg->rip_vers > 0) {
	57	n->rip_dst.sa_family =
	58	htons(n->rip_dst.sa_family);
	59	n->rip_metric = htonl(n->rip_metric);
	60	}
2e74322d SL	61	n++, newsize += sizeof (struct netinfo);
	62	}
	63	if (newsize > 0) {
	64	msg->rip_cmd = RIPCMD_RESPONSE;
	65	newsize += sizeof (int);
4f4bffaa	66	(*afp->af_output)(s, 0, from, newsize);
2e74322d SL	67	}
	68	return;
	69
	70	case RIPCMD_TRACEON:
	71	case RIPCMD_TRACEOFF:
b7e4f8be	72	/* verify message came from a privileged port */
2e74322d SL	73	if ((*afp->af_portcheck)(from) == 0)
	74	return;
	75	packet[size] = '\0';
	76	if (msg->rip_cmd == RIPCMD_TRACEON)
	77	traceon(msg->rip_tracefile);
	78	else
	79	traceoff();
	80	return;
	81
	82	case RIPCMD_RESPONSE:
	83	/* verify message came from a router */
	84	if ((*afp->af_portmatch)(from) == 0)
	85	return;
	86	(*afp->af_canon)(from);
	87	/* are we talking to ourselves? */
	88	ifp = if_ifwithaddr(from);
	89	if (ifp) {
	90	rt = rtfind(from);
b7e4f8be	91	if (rt == 0 \|\| (rt->rt_state & RTS_INTERFACE) == 0)
2e74322d SL	92	addrouteforif(ifp);
	93	else
	94	rt->rt_timer = 0;
	95	return;
	96	}
f1e15e15 MK	97	/*
	98	* Update timer for interface on which the packet arrived.
	99	* If from other end of a point-to-point link that isn't
	100	* in the routing tables, (re-)add the route.
	101	*/
b7e4f8be MK	102	if ((rt = rtfind(from)) && (rt->rt_state & RTS_INTERFACE))
b7e4f8be MK	103	rt->rt_timer = 0;
f1e15e15 MK	104	else if (ifp = if_ifwithdstaddr(from))
f1e15e15 MK	105	addrouteforif(ifp);
2e74322d SL	106	size -= 4 * sizeof (char);
	107	n = msg->rip_nets;
	108	for (; size > 0; size -= sizeof (struct netinfo), n++) {
	109	if (size < sizeof (struct netinfo))
	110	break;
55d340a4 SL	111	if (msg->rip_vers > 0) {
	112	n->rip_dst.sa_family =
	113	ntohs(n->rip_dst.sa_family);
	114	n->rip_metric = ntohl(n->rip_metric);
	115	}
d5568f13 MK	116	if ((unsigned) n->rip_metric >= HOPCNT_INFINITY)
d5568f13 MK	117	continue;
ed36994a MK	118	if (n->rip_dst.sa_family >= AF_MAX)
	119	continue;
	120	afp = &afswitch[n->rip_dst.sa_family];
d5568f13	121	if (((*afp->af_checkhost)(&n->rip_dst)) == 0)
2e74322d SL	122	continue;
	123	rt = rtlookup(&n->rip_dst);
	124	if (rt == 0) {
	125	rtadd(&n->rip_dst, from, n->rip_metric, 0);
	126	continue;
	127	}
	128
	129	/*
38ca17a8 MK	130	* Update if from gateway and different,
38ca17a8 MK	131	* shorter, or getting stale and equivalent.
2e74322d	132	*/
38ca17a8 MK	133	if ((equal(from, &rt->rt_router) &&
38ca17a8 MK	134	n->rip_metric != rt->rt_metric ) \|\|
b7e4f8be	135	(unsigned) (n->rip_metric) < rt->rt_metric \|\|
2e74322d SL	136	(rt->rt_timer > (EXPIRE_TIME/2) &&
	137	rt->rt_metric == n->rip_metric)) {
	138	rtchange(rt, from, n->rip_metric);
	139	rt->rt_timer = 0;
	140	}
	141	}
	142	return;
	143	}
	144	}