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/* $OpenBSD: hello.c,v 1.2 2005/01/28 17:53:33 norby Exp $ */
/*
* Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org>
* Copyright (c) 2004, 2005 Esben Norby <norby@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 <netinet/in.h>
#include <arpa/inet.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <stdlib.h>
#include <string.h>
#include <event.h>
#include "ospfd.h"
#include "ospf.h"
#include "log.h"
#include "ospfe.h"
extern struct ospfd_conf *oeconf;
/* hello packet handling */
int
send_hello(struct iface *iface)
{
struct sockaddr_in dst;
struct hello_hdr *hello;
struct nbr *nbr;
char *buf;
char *ptr;
int ret = 0;
if (iface->passive)
return (0);
/* XXX use buffer API instead for better decoupling */
if ((ptr = buf = calloc(1, READ_BUF_SIZE)) == NULL)
fatal("send_hello");
dst.sin_family = AF_INET;
dst.sin_len = sizeof(struct sockaddr_in);
switch (iface->type) {
case IF_TYPE_POINTOPOINT:
case IF_TYPE_BROADCAST:
inet_aton(AllSPFRouters, &dst.sin_addr);
break;
case IF_TYPE_NBMA:
case IF_TYPE_POINTOMULTIPOINT:
case IF_TYPE_VIRTUALLINK:
/* XXX these networks need to be preconfigured */
/* dst.sin_addr.s_addr = nbr->addr.s_addr; */
inet_aton(AllSPFRouters, &dst.sin_addr);
break;
default:
fatalx("send_hello: unknown interface type");
}
/* OSPF header */
gen_ospf_hdr(ptr, iface, PACKET_TYPE_HELLO);
ptr += sizeof(struct ospf_hdr);
/* hello header */
hello = (struct hello_hdr *)ptr;
hello->mask = iface->mask.s_addr;
hello->hello_interval = htons(iface->hello_interval);
hello->opts = oeconf->options;
hello->rtr_priority = iface->priority;
hello->rtr_dead_interval = htonl(iface->dead_interval);
if (iface->dr)
hello->d_rtr = iface->dr->addr.s_addr;
if (iface->bdr)
hello->bd_rtr = iface->bdr->addr.s_addr;
ptr += sizeof(*hello);
/* active neighbor(s) */
LIST_FOREACH(nbr, &iface->nbr_list, entry) {
if (ptr - buf > iface->mtu - PACKET_HDR) {
log_warnx("send_hello: too many neighbors on "
"interface %s", iface->name);
break;
}
if ((nbr->state >= NBR_STA_INIT) && (nbr != iface->self)) {
memcpy(ptr, &nbr->id, sizeof(nbr->id));
ptr += sizeof(nbr->id);
}
}
/* update authentication and calculate checksum */
auth_gen(buf, ptr - buf, iface);
if ((ret = send_packet(iface, buf, (ptr - buf), &dst)) == -1)
log_warnx("send_hello: error sending packet on "
"interface %s", iface->name);
free(buf);
return (ret);
}
void
recv_hello(struct iface *iface, struct in_addr src, u_int32_t rtr_id, char *buf,
u_int16_t len)
{
struct hello_hdr hello;
struct nbr *nbr = NULL;
u_int32_t nbr_id;
int twoway = 0, nbr_change = 0;
if (len < sizeof(hello) && (len & 0x03)) {
log_warnx("recv_hello: bad packet size, interface %s",
iface->name);
return;
}
memcpy(&hello, buf, sizeof(hello));
buf += sizeof(hello);
len -= sizeof(hello);
if (iface->type != IF_TYPE_POINTOPOINT &&
iface->type != IF_TYPE_VIRTUALLINK)
if (hello.mask != iface->mask.s_addr) {
log_warnx("recv_hello: invalid netmask, interface %s",
iface->name);
return;
}
if (ntohs(hello.hello_interval) != iface->hello_interval) {
log_warnx("recv_hello: invalid hello-interval %d, "
"interface %s", ntohs(hello.hello_interval),
iface->name);
return;
}
if (ntohl(hello.rtr_dead_interval) != iface->dead_interval) {
log_warnx("recv_hello: invalid router-dead-interval %d, "
"interface %s", ntohl(hello.rtr_dead_interval),
iface->name);
return;
}
if ((hello.opts & OSPF_OPTION_E && iface->area->stub) ||
((hello.opts & OSPF_OPTION_E) == 0 && !iface->area->stub)) {
log_warnx("recv_hello: ExternalRoutingCapability mismatch, "
"interface %s", iface->name);
return;
}
switch (iface->type) {
case IF_TYPE_POINTOPOINT:
case IF_TYPE_VIRTUALLINK:
/* match router-id */
LIST_FOREACH(nbr, &iface->nbr_list, entry) {
if (nbr == iface->self)
continue;
if (nbr->id.s_addr == rtr_id)
break;
}
break;
case IF_TYPE_BROADCAST:
case IF_TYPE_NBMA:
case IF_TYPE_POINTOMULTIPOINT:
/* match src IP */
LIST_FOREACH(nbr, &iface->nbr_list, entry) {
if (nbr == iface->self)
continue;
if (nbr->addr.s_addr == src.s_addr)
break;
}
break;
default:
fatalx("recv_hello: unknown interface type");
}
if (!nbr)
nbr = nbr_new(rtr_id, iface, 0);
/* actually the neighbor address shouldn't be stored on virtual links */
nbr->addr.s_addr = src.s_addr;
nbr->options = hello.opts;
nbr_fsm(nbr, NBR_EVT_HELLO_RCVD);
while (len >= sizeof(nbr_id)) {
memcpy(&nbr_id, buf, sizeof(nbr_id));
if (nbr_id == iface->rtr_id.s_addr) {
/* seen myself */
if (nbr->state < NBR_STA_XSTRT)
twoway = 1;
break;
}
buf += sizeof(nbr_id);
len -= sizeof(nbr_id);
}
if (len == 0) {
nbr_fsm(nbr, NBR_EVT_1_WAY_RCVD);
/* set neighbor parameters */
nbr->dr.s_addr = hello.d_rtr;
nbr->bdr.s_addr = hello.bd_rtr;
nbr->priority = hello.rtr_priority;
return;
}
if (nbr->priority != hello.rtr_priority) {
nbr->priority = hello.rtr_priority;
nbr_change = 1;
}
if (iface->state == IF_STA_WAITING &&
((nbr->dr.s_addr == nbr->addr.s_addr &&
nbr->bdr.s_addr == 0) || nbr->bdr.s_addr == nbr->addr.s_addr))
if_fsm(iface, IF_EVT_BACKUP_SEEN);
if ((nbr->addr.s_addr == nbr->dr.s_addr &&
nbr->addr.s_addr != hello.d_rtr) ||
(nbr->addr.s_addr != nbr->dr.s_addr &&
nbr->addr.s_addr == hello.d_rtr))
/* neighbor changed from or to DR */
nbr_change = 1;
if ((nbr->addr.s_addr == nbr->bdr.s_addr &&
nbr->addr.s_addr != hello.bd_rtr) ||
(nbr->addr.s_addr != nbr->bdr.s_addr &&
nbr->addr.s_addr == hello.bd_rtr))
/* neighbor changed from or to BDR */
nbr_change = 1;
nbr->dr.s_addr = hello.d_rtr;
nbr->bdr.s_addr = hello.bd_rtr;
if (twoway) {
/*
* event 2 way recieved needs to be delayed after the
* interface neighbor change check else the DR and BDR
* may not be set correctly.
*/
nbr_fsm(nbr, NBR_EVT_2_WAY_RCVD);
}
if (nbr_change)
if_fsm(iface, IF_EVT_NBR_CHNG);
/* TODO NBMA needs some special handling */
return;
}
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