/*      $OpenBSD: rde_rib.c,v 1.6 2023/03/08 04:43:14 guenther Exp $ */

/*
 * Copyright (c) 2006 Michele Marchetto <mydecay@openbeer.it>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <net/if_types.h>
#include <ctype.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <event.h>

#include "ripd.h"
#include "rip.h"
#include "log.h"
#include "rde.h"

extern struct ripd_conf         *rdeconf;
RB_HEAD(rt_tree, rt_node)        rt;
RB_PROTOTYPE(rt_tree, rt_node, entry, rt_compare)
RB_GENERATE(rt_tree, rt_node, entry, rt_compare)

void     route_action_timeout(int, short, void *);
void     route_action_garbage(int, short, void *);

/* timers */
int
route_start_timeout(struct rt_node *rn)
{
        struct timeval   tv;

        timerclear(&tv);
        tv.tv_sec = ROUTE_TIMEOUT;

        return (evtimer_add(&rn->timeout_timer, &tv));
}

void
route_start_garbage(struct rt_node *rn)
{
        struct timeval   tv;

        timerclear(&tv);
        tv.tv_sec = ROUTE_GARBAGE;

        if (evtimer_pending(&rn->timeout_timer, NULL)) {
                if (evtimer_del(&rn->timeout_timer) == -1)
                        fatal("route_start_garbage");
                evtimer_add(&rn->garbage_timer, &tv);
        }
}

void
route_action_timeout(int fd, short event, void *arg)
{
        struct rt_node  *r = arg;
        struct timeval   tv;

        timerclear(&tv);
        r->metric = INFINITY;
        tv.tv_sec = ROUTE_GARBAGE;

        if (evtimer_add(&r->garbage_timer, &tv) == -1)
                fatal("route_action_timeout");

        rde_send_change_kroute(r);
}

void
route_action_garbage(int fd, short event, void *arg)
{
        struct rt_node  *r = arg;

        rde_send_delete_kroute(r);
        rt_remove(r);
}

void
route_reset_timers(struct rt_node *r)
{
        struct timeval   tv;

        timerclear(&tv);
        tv.tv_sec = ROUTE_TIMEOUT;
        evtimer_del(&r->timeout_timer);
        evtimer_del(&r->garbage_timer);

        evtimer_add(&r->timeout_timer, &tv);
}

/* route table */
void
rt_init(void)
{
        RB_INIT(&rt);
}

int
rt_compare(struct rt_node *a, struct rt_node *b)
{
        if (ntohl(a->prefix.s_addr) < ntohl(b->prefix.s_addr))
                return (-1);
        if (ntohl(a->prefix.s_addr) > ntohl(b->prefix.s_addr))
                return (1);
        if (ntohl(a->netmask.s_addr) < ntohl(b->netmask.s_addr))
                return (-1);
        if (ntohl(a->netmask.s_addr) > ntohl(b->netmask.s_addr))
                return (1);

        return (0);
}

struct rt_node *
rt_find(in_addr_t prefix, in_addr_t netmask)
{
        struct rt_node   s;

        s.prefix.s_addr = prefix;
        s.netmask.s_addr = netmask;

        return (RB_FIND(rt_tree, &rt, &s));
}

struct rt_node *
rt_new_kr(struct kroute *kr)
{
        struct rt_node  *rn;

        if ((rn = calloc(1, sizeof(*rn))) == NULL)
                fatal("rt_new_kr");

        evtimer_set(&rn->timeout_timer, route_action_timeout, rn);
        evtimer_set(&rn->garbage_timer, route_action_garbage, rn);

        rn->prefix.s_addr = kr->prefix.s_addr;
        rn->netmask.s_addr = kr->netmask.s_addr;
        rn->nexthop.s_addr = kr->nexthop.s_addr;
        rn->metric = kr->metric;
        rn->ifindex = kr->ifindex;
        rn->flags = F_KERNEL;

        return (rn);
}

struct rt_node *
rt_new_rr(struct rip_route *e, u_int8_t metric)
{
        struct rt_node  *rn;

        if ((rn = calloc(1, sizeof(*rn))) == NULL)
                fatal("rt_new_rr");

        evtimer_set(&rn->timeout_timer, route_action_timeout, rn);
        evtimer_set(&rn->garbage_timer, route_action_garbage, rn);

        rn->prefix.s_addr = e->address.s_addr;
        rn->netmask.s_addr = e->mask.s_addr;
        rn->nexthop.s_addr = e->nexthop.s_addr;
        rn->metric = metric;
        rn->ifindex = e->ifindex;
        rn->flags = F_RIPD_INSERTED;

        return (rn);
}

int
rt_insert(struct rt_node *r)
{
        if (RB_INSERT(rt_tree, &rt, r) != NULL) {
                log_warnx("rt_insert failed for %s/%u",
                    inet_ntoa(r->prefix), mask2prefixlen(r->netmask.s_addr));
                free(r);
                return (-1);
        }

        return (0);
}

int
rt_remove(struct rt_node *r)
{
        if (RB_REMOVE(rt_tree, &rt, r) == NULL) {
                log_warnx("rt_remove failed for %s/%u",
                    inet_ntoa(r->prefix), mask2prefixlen(r->netmask.s_addr));
                return (-1);
        }

        free(r);
        return (0);
}

void
rt_snap(u_int32_t peerid)
{
        struct rt_node          *r;
        struct rip_route         rr;

        bzero(&rr, sizeof(rr));

        RB_FOREACH(r, rt_tree, &rt) {
                rr.address = r->prefix;
                rr.mask = r->netmask;
                rr.nexthop = r->nexthop;
                rr.metric = r->metric;
                rr.ifindex = r->ifindex;

                rde_imsg_compose_ripe(IMSG_RESPONSE_ADD, peerid, 0, &rr,
                    sizeof(rr));
        }
}

void
rt_dump(pid_t pid)
{
        struct rt_node          *r;
        static struct ctl_rt     rtctl;

        RB_FOREACH(r, rt_tree, &rt) {
                rtctl.prefix.s_addr = r->prefix.s_addr;
                rtctl.netmask.s_addr = r->netmask.s_addr;
                rtctl.nexthop.s_addr = r->nexthop.s_addr;
                rtctl.metric = r->metric;
                rtctl.flags = r->flags;

                rde_imsg_compose_ripe(IMSG_CTL_SHOW_RIB, 0, pid, &rtctl,
                    sizeof(rtctl));
        }
}

void
rt_complete(struct rip_route *rr)
{
        struct rt_node  *rn;

        if ((rn = rt_find(rr->address.s_addr, rr->mask.s_addr)) == NULL)
                rr->metric = INFINITY;
        else
                rr->metric = rn->metric;
}

void
rt_clear(void)
{
        struct rt_node  *r;

        while ((r = RB_MIN(rt_tree, &rt)) != NULL)
                rt_remove(r);
}