xref: /netbsd-src/sbin/routed/output.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1 /*
2  * Copyright (c) 1983, 1988, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 /*static char sccsid[] = "from: @(#)output.c	8.1 (Berkeley) 6/5/93";*/
36 static char *rcsid = "$Id: output.c,v 1.7 1994/12/18 05:43:56 cgd Exp $";
37 #endif /* not lint */
38 
39 /*
40  * Routing Table Management Daemon
41  */
42 #include "defs.h"
43 
44 /*
45  * Apply the function "f" to all non-passive
46  * interfaces.  If the interface supports the
47  * use of broadcasting use it, otherwise address
48  * the output to the known router.
49  */
50 void
51 toall(f, rtstate, skipif)
52 	int (*f)();
53 	int rtstate;
54 	struct interface *skipif;
55 {
56 	register struct interface *ifp;
57 	register struct sockaddr *dst;
58 	register int flags;
59 	extern struct interface *ifnet;
60 
61 	for (ifp = ifnet; ifp; ifp = ifp->int_next) {
62 		if (ifp->int_flags & IFF_PASSIVE || ifp == skipif)
63 			continue;
64 		dst = ifp->int_flags & IFF_BROADCAST ? &ifp->int_broadaddr :
65 		      ifp->int_flags & IFF_POINTOPOINT ? &ifp->int_dstaddr :
66 		      &ifp->int_addr;
67 		flags = ifp->int_flags & IFF_INTERFACE ? MSG_DONTROUTE : 0;
68 		(*f)(dst, flags, ifp, rtstate);
69 	}
70 }
71 
72 /*
73  * Output a preformed packet.
74  */
75 /*ARGSUSED*/
76 int
77 sndmsg(dst, flags, ifp, rtstate)
78 	struct sockaddr *dst;
79 	int flags;
80 	struct interface *ifp;
81 	int rtstate;
82 {
83 
84 	(*afswitch[dst->sa_family].af_output)(s, flags,
85 		dst, sizeof (struct rip));
86 	TRACE_OUTPUT(ifp, dst, sizeof (struct rip));
87 }
88 
89 /*
90  * Supply dst with the contents of the routing tables.
91  * If this won't fit in one packet, chop it up into several.
92  */
93 int
94 supply(dst, flags, ifp, rtstate)
95 	struct sockaddr *dst;
96 	int flags;
97 	register struct interface *ifp;
98 	int rtstate;
99 {
100 	register struct rt_entry *rt;
101 	register struct netinfo *n = msg->rip_nets;
102 	register struct rthash *rh;
103 	struct rthash *base = hosthash;
104 	int doinghost = 1, size;
105 	int (*output)() = afswitch[dst->sa_family].af_output;
106 	int (*sendroute)() = afswitch[dst->sa_family].af_sendroute;
107 	int npackets = 0;
108 
109 	msg->rip_cmd = RIPCMD_RESPONSE;
110 	msg->rip_vers = RIPVERSION;
111 	memset(msg->rip_res1, 0, sizeof(msg->rip_res1));
112 again:
113 	for (rh = base; rh < &base[ROUTEHASHSIZ]; rh++)
114 	for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
115 		/*
116 		 * Don't resend the information on the network
117 		 * from which it was received (unless sending
118 		 * in response to a query).
119 		 */
120 		if (ifp && rt->rt_ifp == ifp &&
121 		    (rt->rt_state & RTS_INTERFACE) == 0)
122 			continue;
123 		if (rt->rt_state & RTS_EXTERNAL)
124 			continue;
125 		/*
126 		 * For dynamic updates, limit update to routes
127 		 * with the specified state.
128 		 */
129 		if (rtstate && (rt->rt_state & rtstate) == 0)
130 			continue;
131 		/*
132 		 * Limit the spread of subnet information
133 		 * to those who are interested.
134 		 */
135 		if (doinghost == 0 && rt->rt_state & RTS_SUBNET) {
136 			if (rt->rt_dst.sa_family != dst->sa_family)
137 				continue;
138 			if ((*sendroute)(rt, dst) == 0)
139 				continue;
140 		}
141 		size = (char *)n - packet;
142 		if (size > MAXPACKETSIZE - sizeof (struct netinfo)) {
143 			TRACE_OUTPUT(ifp, dst, size);
144 			(*output)(s, flags, dst, size);
145 			/*
146 			 * If only sending to ourselves,
147 			 * one packet is enough to monitor interface.
148 			 */
149 			if (ifp && (ifp->int_flags &
150 			   (IFF_BROADCAST | IFF_POINTOPOINT | IFF_REMOTE)) == 0)
151 				return;
152 			n = msg->rip_nets;
153 			npackets++;
154 		}
155 		n->rip_dst = rt->rt_dst;
156 #if BSD < 198810
157 		if (sizeof(n->rip_dst.sa_family) > 1)	/* XXX */
158 		n->rip_dst.sa_family = htons(n->rip_dst.sa_family);
159 #else
160 #define osa(x) ((struct osockaddr *)(&(x)))
161 		osa(n->rip_dst)->sa_family = htons(n->rip_dst.sa_family);
162 #endif
163 		n->rip_metric = htonl(rt->rt_metric);
164 		n++;
165 	}
166 	if (doinghost) {
167 		doinghost = 0;
168 		base = nethash;
169 		goto again;
170 	}
171 	if (n != msg->rip_nets || (npackets == 0 && rtstate == 0)) {
172 		size = (char *)n - packet;
173 		TRACE_OUTPUT(ifp, dst, size);
174 		(*output)(s, flags, dst, size);
175 	}
176 }
177