xref: /netbsd/usr.sbin/mrouted/route.h (revision c60d41a9)
1 /*	$NetBSD: route.h,v 1.6 2003/03/05 21:05:40 wiz Exp $	*/
2 
3 /*
4  * The mrouted program is covered by the license in the accompanying file
5  * named "LICENSE".  Use of the mrouted program represents acceptance of
6  * the terms and conditions listed in that file.
7  *
8  * The mrouted program is COPYRIGHT 1989 by The Board of Trustees of
9  * Leland Stanford Junior University.
10  */
11 
12 /*
13  * Routing Table Entry, one per subnet from which a multicast could originate.
14  * (Note: all addresses, subnet numbers and masks are kept in NETWORK order.)
15  *
16  * The Routing Table is stored as a doubly-linked list of these structures,
17  * ordered by decreasing value of rt_originmask and, secondarily, by
18  * decreasing value of rt_origin within each rt_originmask value.
19  * This data structure is efficient for generating route reports, whether
20  * full or partial, for processing received full reports, for clearing the
21  * CHANGED flags, and for periodically advancing the timers in all routes.
22  * It is not so efficient for updating a small number of routes in response
23  * to a partial report.  In a stable topology, the latter are rare; if they
24  * turn out to be costing a lot, we can add an auxiliary hash table for
25  * faster access to arbitrary route entries.
26  */
27 struct rtentry {
28     struct rtentry  *rt_next;		/* link to next entry MUST BE FIRST */
29     u_int32_t	     rt_origin;		/* subnet origin of multicasts      */
30     u_int32_t	     rt_originmask;	/* subnet mask for origin           */
31     short	     rt_originwidth;	/* # bytes of origin subnet number  */
32     u_char	     rt_metric;		/* cost of route back to origin     */
33     u_char	     rt_flags;		/* RTF_ flags defined below         */
34     u_int32_t	     rt_gateway;	/* first-hop gateway back to origin */
35     vifi_t	     rt_parent;	    	/* incoming vif (ie towards origin) */
36     vifbitmap_t	     rt_children;	/* outgoing children vifs           */
37     vifbitmap_t	     rt_leaves;		/* subset of outgoing children vifs */
38     u_int32_t	    *rt_dominants;      /* per vif dominant gateways        */
39     u_int32_t	    *rt_subordinates;   /* per vif subordinate gateways     */
40     u_int	    *rt_leaf_timers;	/* per vif leaf confirmation timers */
41     u_int	     rt_timer;		/* for timing out the route entry   */
42     struct rtentry  *rt_prev;		/* link to previous entry           */
43     struct gtable   *rt_groups;		/* link to active groups 	    */
44 };
45 
46 #define	RTF_CHANGED		0x01	/* route changed but not reported   */
47 #define RTF_LEAF_TIMING		0x02	/* some leaf timers are running     */
48 
49 #define ALL_ROUTES	0		/* possible arguments to report()   */
50 #define CHANGED_ROUTES	1		/*  and report_to_all_neighbors()   */
51