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|
/* $OpenBSD: rde.c,v 1.6 2007/04/09 20:45:52 michele Exp $ */
/*
* Copyright (c) 2006 Michele Marchetto <mydecay@openbeer.it>
* Copyright (c) 2004, 2005 Claudio Jeker <claudio@openbsd.org>
* Copyright (c) 2004 Esben Norby <norby@openbsd.org>
* Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
*
* 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/socket.h>
#include <sys/queue.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <err.h>
#include <errno.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <pwd.h>
#include <unistd.h>
#include <event.h>
#include "ripd.h"
#include "rip.h"
#include "ripe.h"
#include "log.h"
#include "rde.h"
struct ripd_conf *rdeconf = NULL;
struct imsgbuf *ibuf_ripe;
struct imsgbuf *ibuf_main;
void rde_sig_handler(int, short, void *);
void rde_shutdown(void);
void rde_dispatch_imsg(int, short, void *);
void rde_dispatch_parent(int, short, void *);
int rde_imsg_compose_ripe(int, u_int32_t, pid_t, void *, u_int16_t);
int rde_check_route(struct rip_route *);
void triggered_update(struct rt_node *);
/* ARGSUSED */
void
rde_sig_handler(int sig, short event, void *arg)
{
/*
* signal handler rules don't apply, libevent decouples for us
*/
switch (sig) {
case SIGINT:
case SIGTERM:
rde_shutdown();
/* NOTREACHED */
default:
fatalx("unexpected signal");
}
}
/* route decision engine */
pid_t
rde(struct ripd_conf *xconf, int pipe_parent2rde[2], int pipe_ripe2rde[2],
int pipe_parent2ripe[2])
{
struct event ev_sigint, ev_sigterm;
struct passwd *pw;
struct redistribute *r;
pid_t pid;
switch (pid = fork()) {
case -1:
fatal("cannot fork");
/* NOTREACHED */
case 0:
break;
default:
return (pid);
}
rdeconf = xconf;
if ((pw = getpwnam(RIPD_USER)) == NULL)
fatal("getpwnam");
if (chroot(pw->pw_dir) == -1)
fatal("chroot");
if (chdir("/") == -1)
fatal("chdir(\"/\")");
setproctitle("route decision engine");
ripd_process = PROC_RDE_ENGINE;
if (setgroups(1, &pw->pw_gid) ||
setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
fatal("can't drop privileges");
event_init();
/* setup signal handler */
signal_set(&ev_sigint, SIGINT, rde_sig_handler, NULL);
signal_set(&ev_sigterm, SIGTERM, rde_sig_handler, NULL);
signal_add(&ev_sigint, NULL);
signal_add(&ev_sigterm, NULL);
signal(SIGPIPE, SIG_IGN);
/* setup pipes */
close(pipe_ripe2rde[0]);
close(pipe_parent2rde[0]);
close(pipe_parent2ripe[0]);
close(pipe_parent2ripe[1]);
if ((ibuf_ripe = malloc(sizeof(struct imsgbuf))) == NULL ||
(ibuf_main = malloc(sizeof(struct imsgbuf))) == NULL)
fatal(NULL);
imsg_init(ibuf_ripe, pipe_ripe2rde[1], rde_dispatch_imsg);
imsg_init(ibuf_main, pipe_parent2rde[1], rde_dispatch_parent);
/* setup event handler */
ibuf_ripe->events = EV_READ;
event_set(&ibuf_ripe->ev, ibuf_ripe->fd, ibuf_ripe->events,
ibuf_ripe->handler, ibuf_ripe);
event_add(&ibuf_ripe->ev, NULL);
ibuf_main->events = EV_READ;
event_set(&ibuf_main->ev, ibuf_main->fd, ibuf_main->events,
ibuf_main->handler, ibuf_main);
event_add(&ibuf_main->ev, NULL);
rt_init();
/* remove unneeded config stuff */
while ((r = SIMPLEQ_FIRST(&rdeconf->redist_list)) != NULL) {
SIMPLEQ_REMOVE_HEAD(&rdeconf->redist_list, entry);
free(r);
}
event_dispatch();
rde_shutdown();
/* NOTREACHED */
return (0);
}
void
rde_shutdown(void)
{
rt_clear();
msgbuf_clear(&ibuf_ripe->w);
free(ibuf_ripe);
msgbuf_clear(&ibuf_main->w);
free(ibuf_main);
free(rdeconf);
log_info("route decision engine exiting");
_exit(0);
}
/* imesg */
int
rde_imsg_compose_ripe(int type, u_int32_t peerid, pid_t pid, void *data,
u_int16_t datalen)
{
return (imsg_compose(ibuf_ripe, type, peerid, pid, data, datalen));
}
/* ARGSUSED */
void
rde_dispatch_imsg(int fd, short event, void *bula)
{
struct imsgbuf *ibuf = bula;
struct rip_route rr;
struct imsg imsg;
int n;
switch (event) {
case EV_READ:
if ((n = imsg_read(ibuf)) == -1)
fatal("imsg_read error");
if (n == 0) /* connection closed */
fatalx("pipe closed");
break;
case EV_WRITE:
if (msgbuf_write(&ibuf->w) == -1)
fatal("msgbuf_write");
imsg_event_add(ibuf);
return;
default:
fatalx("unknown event");
}
for (;;) {
if ((n = imsg_get(ibuf, &imsg)) == -1)
fatal("rde_dispatch_imsg: imsg_read error");
if (n == 0)
break;
switch (imsg.hdr.type) {
case IMSG_ROUTE_FEED:
if (imsg.hdr.len - IMSG_HEADER_SIZE != sizeof(rr))
fatalx("invalid size of RDE request");
memcpy(&rr, imsg.data, sizeof(rr));
if (rde_check_route(&rr) == -1)
log_debug("rde_dispatch_imsg: "
"packet malformed\n");
break;
case IMSG_FULL_REQUEST:
bzero(&rr, sizeof(rr));
/* AFI == 0 && metric == INFINITY request the
whole routing table
*/
rr.metric = INFINITY;
rde_imsg_compose_ripe(IMSG_REQUEST_ADD, 0,
0, &rr, sizeof(rr));
rde_imsg_compose_ripe(IMSG_SEND_REQUEST, 0,
0, NULL, 0);
break;
case IMSG_FULL_RESPONSE:
rt_snap(imsg.hdr.peerid);
rde_imsg_compose_ripe(IMSG_SEND_RESPONSE,
imsg.hdr.peerid, 0, NULL, 0);
break;
case IMSG_ROUTE_REQUEST:
if (imsg.hdr.len - IMSG_HEADER_SIZE != sizeof(rr))
fatalx("invalid size of RDE request");
memcpy(&rr, imsg.data, sizeof(rr));
rt_complete(&rr);
rde_imsg_compose_ripe(IMSG_RESPONSE_ADD,
imsg.hdr.peerid, 0, &rr, sizeof(rr));
break;
case IMSG_ROUTE_REQUEST_END:
rde_imsg_compose_ripe(IMSG_SEND_RESPONSE,
imsg.hdr.peerid, 0, NULL, 0);
break;
case IMSG_CTL_SHOW_RIB:
rt_dump(imsg.hdr.pid);
imsg_compose(ibuf_ripe, IMSG_CTL_END, 0, imsg.hdr.pid,
NULL, 0);
break;
default:
log_debug("rde_dispatch_msg: unexpected imsg %d",
imsg.hdr.type);
break;
}
imsg_free(&imsg);
}
imsg_event_add(ibuf);
}
/* ARGSUSED */
void
rde_dispatch_parent(int fd, short event, void *bula)
{
struct imsg imsg;
struct rt_node *rt;
struct kroute kr;
struct imsgbuf *ibuf = bula;
ssize_t n;
switch (event) {
case EV_READ:
if ((n = imsg_read(ibuf)) == -1)
fatal("imsg_read error");
if (n == 0) /* connection closed */
fatalx("pipe closed");
break;
case EV_WRITE:
if (msgbuf_write(&ibuf->w) == -1)
fatal("msgbuf_write");
imsg_event_add(ibuf);
return;
default:
fatalx("unknown event");
}
for (;;) {
if ((n = imsg_get(ibuf, &imsg)) == -1)
fatal("rde_dispatch_parent: imsg_read error");
if (n == 0)
break;
switch (imsg.hdr.type) {
case IMSG_NETWORK_ADD:
if (imsg.hdr.len - IMSG_HEADER_SIZE != sizeof(kr)) {
log_warnx("rde_dispatch: wrong imsg len");
break;
}
memcpy(&kr, imsg.data, sizeof(kr));
rt = rt_new_kr(&kr);
rt_insert(rt);
break;
case IMSG_NETWORK_DEL:
if (imsg.hdr.len - IMSG_HEADER_SIZE != sizeof(kr)) {
log_warnx("rde_dispatch: wrong imsg len");
break;
}
memcpy(&kr, imsg.data, sizeof(kr));
if ((rt = rt_find(kr.prefix.s_addr,
kr.netmask.s_addr)) != NULL)
rt_remove(rt);
break;
case IMSG_KROUTE_GET:
if (imsg.hdr.len - IMSG_HEADER_SIZE != sizeof(kr)) {
log_warnx("rde_dispatch: wrong imsg len");
break;
}
memcpy(&kr, imsg.data, sizeof(kr));
if ((rt = rt_find(kr.prefix.s_addr,
kr.netmask.s_addr)) != NULL)
rde_send_change_kroute(rt);
else
/* should not happen */
imsg_compose(ibuf_main, IMSG_KROUTE_DELETE, 0,
0, &kr, sizeof(kr));
break;
default:
log_debug("rde_dispatch_parent: unexpected imsg %d",
imsg.hdr.type);
break;
}
imsg_free(&imsg);
}
imsg_event_add(ibuf);
}
void
rde_send_change_kroute(struct rt_node *r)
{
struct kroute kr;
bzero(&kr, sizeof(kr));
kr.prefix.s_addr = r->prefix.s_addr;
kr.nexthop.s_addr = r->nexthop.s_addr;
kr.netmask.s_addr = r->netmask.s_addr;
kr.metric = r->metric;
kr.flags = r->flags;
kr.ifindex = r->ifindex;
imsg_compose(ibuf_main, IMSG_KROUTE_CHANGE, 0, 0, &kr, sizeof(kr));
}
void
rde_send_delete_kroute(struct rt_node *r)
{
struct kroute kr;
bzero(&kr, sizeof(kr));
kr.prefix.s_addr = r->prefix.s_addr;
kr.nexthop.s_addr = r->nexthop.s_addr;
kr.netmask.s_addr = r->netmask.s_addr;
kr.metric = r->metric;
kr.flags = r->flags;
kr.ifindex = r->ifindex;
imsg_compose(ibuf_main, IMSG_KROUTE_DELETE, 0, 0, &kr, sizeof(kr));
}
int
rde_check_route(struct rip_route *e)
{
struct timeval tv, now;
struct rt_node *rn;
struct iface *iface;
int metric;
if ((e->nexthop.s_addr & htonl(IN_CLASSA_NET)) ==
htonl(INADDR_LOOPBACK & IN_CLASSA_NET) ||
(e->nexthop.s_addr == INADDR_ANY))
return (-1);
if ((e->address.s_addr & htonl(IN_CLASSA_NET)) ==
htonl(INADDR_LOOPBACK & IN_CLASSA_NET))
return (-1);
if ((iface = if_find_index(e->ifindex)) == NULL)
return (-1);
metric = MIN(INFINITY, e->metric + iface->cost);
if ((rn = rt_find(e->address.s_addr, e->mask.s_addr)) == NULL) {
if (metric >= INFINITY)
return (0);
rn = rt_new_rr(e, metric);
rt_insert(rn);
rde_send_change_kroute(rn);
route_start_timeout(rn);
triggered_update(rn);
} else {
/*
* XXX don't we have to track all incoming routes?
* what happens if the kernel route is removed later.
*/
if (rn->flags & F_KERNEL)
return (0);
if (metric < rn->metric) {
rn->metric = metric;
rn->nexthop.s_addr = e->nexthop.s_addr;
rn->ifindex = e->ifindex;
rde_send_change_kroute(rn);
triggered_update(rn);
} else if (e->nexthop.s_addr == rn->nexthop.s_addr &&
metric > rn->metric) {
rn->metric = metric;
rde_send_change_kroute(rn);
triggered_update(rn);
if (rn->metric == INFINITY)
route_start_garbage(rn);
} else if (e->nexthop.s_addr != rn->nexthop.s_addr &&
metric == rn->metric) {
/* If the new metric is the same as the old one,
* examine the timeout for the existing route. If it
* is at least halfway to the expiration point, switch
* to the new route.
*/
timerclear(&tv);
gettimeofday(&now, NULL);
evtimer_pending(&rn->timeout_timer, &tv);
if (tv.tv_sec - now.tv_sec < ROUTE_TIMEOUT / 2) {
rn->nexthop.s_addr = e->nexthop.s_addr;
rn->ifindex = e->ifindex;
rde_send_change_kroute(rn);
}
}
if (e->nexthop.s_addr == rn->nexthop.s_addr &&
rn->metric < INFINITY)
route_reset_timers(rn);
}
return (0);
}
void
triggered_update(struct rt_node *rn)
{
struct rip_route rr;
rr.address.s_addr = rn->prefix.s_addr;
rr.mask.s_addr = rn->netmask.s_addr;
rr.nexthop.s_addr = rn->nexthop.s_addr;
rr.metric = rn->metric;
rr.ifindex = rn->ifindex;
rde_imsg_compose_ripe(IMSG_SEND_TRIGGERED_UPDATE, 0, 0, &rr,
sizeof(struct rip_route));
}
|