/*      $NetBSD: route.h,v 1.6 2003/03/05 21:05:40 wiz Exp $    */

/*
 * The mrouted program is covered by the license in the accompanying file
 * named "LICENSE".  Use of the mrouted program represents acceptance of
 * the terms and conditions listed in that file.
 *
 * The mrouted program is COPYRIGHT 1989 by The Board of Trustees of
 * Leland Stanford Junior University.
 */

/*
 * Routing Table Entry, one per subnet from which a multicast could originate.
 * (Note: all addresses, subnet numbers and masks are kept in NETWORK order.)
 *
 * The Routing Table is stored as a doubly-linked list of these structures,
 * ordered by decreasing value of rt_originmask and, secondarily, by
 * decreasing value of rt_origin within each rt_originmask value.
 * This data structure is efficient for generating route reports, whether
 * full or partial, for processing received full reports, for clearing the
 * CHANGED flags, and for periodically advancing the timers in all routes.
 * It is not so efficient for updating a small number of routes in response
 * to a partial report.  In a stable topology, the latter are rare; if they
 * turn out to be costing a lot, we can add an auxiliary hash table for
 * faster access to arbitrary route entries.
 */
struct rtentry {
    struct rtentry  *rt_next;           /* link to next entry MUST BE FIRST */
    u_int32_t        rt_origin;         /* subnet origin of multicasts      */
    u_int32_t        rt_originmask;     /* subnet mask for origin           */
    short            rt_originwidth;    /* # bytes of origin subnet number  */
    u_char           rt_metric;         /* cost of route back to origin     */
    u_char           rt_flags;          /* RTF_ flags defined below         */
    u_int32_t        rt_gateway;        /* first-hop gateway back to origin */
    vifi_t           rt_parent;         /* incoming vif (ie towards origin) */
    vifbitmap_t      rt_children;       /* outgoing children vifs           */
    vifbitmap_t      rt_leaves;         /* subset of outgoing children vifs */
    u_int32_t       *rt_dominants;      /* per vif dominant gateways        */
    u_int32_t       *rt_subordinates;   /* per vif subordinate gateways     */
    u_int           *rt_leaf_timers;    /* per vif leaf confirmation timers */
    u_int            rt_timer;          /* for timing out the route entry   */
    struct rtentry  *rt_prev;           /* link to previous entry           */
    struct gtable   *rt_groups;         /* link to active groups            */
};

#define RTF_CHANGED             0x01    /* route changed but not reported   */
#define RTF_LEAF_TIMING         0x02    /* some leaf timers are running     */

#define ALL_ROUTES      0               /* possible arguments to report()   */
#define CHANGED_ROUTES  1               /*  and report_to_all_neighbors()   */