bird/proto/ospf/lsreq.c
Ondrej Zajicek (work) bc591061f6 OSPF: Packets on PtP networks should be always sent to AllSPFRouters
As specified in RFC 2328 8.1: "On physical point-to-point networks,
the IP destination is always set to the address AllSPFRouters."

Note that this likely break setups with multiple neighbors on a network
configured as PtP, which worked before. These should be configured as
PtMP.

Thanks to Senthil Kumar Nagappan for the original patch and to Joakim
Tjernlund for suggestions.
2021-05-09 15:26:13 +02:00

146 lines
3.5 KiB
C

/*
* BIRD -- OSPF
*
* (c) 2000--2004 Ondrej Filip <feela@network.cz>
* (c) 2009--2014 Ondrej Zajicek <santiago@crfreenet.org>
* (c) 2009--2014 CZ.NIC z.s.p.o.
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include "ospf.h"
/*
struct ospf_lsreq_packet
{
struct ospf_packet hdr;
// union ospf_auth auth;
struct ospf_lsreq_header lsrs[];
};
*/
static inline void
ospf_lsreq_body(struct ospf_proto *p, struct ospf_packet *pkt,
struct ospf_lsreq_header **body, uint *count)
{
uint plen = ntohs(pkt->length);
uint hlen = ospf_pkt_hdrlen(p);
*body = ((void *) pkt) + hlen;
*count = (plen - hlen) / sizeof(struct ospf_lsreq_header);
}
static void
ospf_dump_lsreq(struct ospf_proto *p, struct ospf_packet *pkt)
{
struct ospf_lsreq_header *lsrs;
uint i, lsr_count;
ASSERT(pkt->type == LSREQ_P);
ospf_dump_common(p, pkt);
ospf_lsreq_body(p, pkt, &lsrs, &lsr_count);
for (i = 0; i < lsr_count; i++)
log(L_TRACE "%s: LSR Type: %04x, Id: %R, Rt: %R", p->p.name,
ntohl(lsrs[i].type), ntohl(lsrs[i].id), ntohl(lsrs[i].rt));
}
void
ospf_send_lsreq(struct ospf_proto *p, struct ospf_neighbor *n)
{
struct ospf_iface *ifa = n->ifa;
struct ospf_lsreq_header *lsrs;
struct top_hash_entry *req;
struct ospf_packet *pkt;
uint i, lsr_max, length;
/* RFC 2328 10.9 */
/* ASSERT((n->state >= NEIGHBOR_EXCHANGE) && !EMPTY_SLIST(n->lsrql)); */
pkt = ospf_tx_buffer(ifa);
ospf_pkt_fill_hdr(ifa, pkt, LSREQ_P);
ospf_lsreq_body(p, pkt, &lsrs, &lsr_max);
i = 0;
WALK_SLIST(req, n->lsrql)
{
if (i == lsr_max)
break;
DBG("Requesting %uth LSA: Type: %04u, ID: %R, RT: %R, SN: 0x%x, Age %u\n",
i, req->lsa_type, req->lsa.id, req->lsa.rt, req->lsa.sn, req->lsa.age);
u32 etype = lsa_get_etype(&req->lsa, p);
lsrs[i].type = htonl(etype);
lsrs[i].rt = htonl(req->lsa.rt);
lsrs[i].id = htonl(req->lsa.id);
i++;
}
/* We store the position to see whether requested LSAs have been received */
n->lsrqi = req;
length = ospf_pkt_hdrlen(p) + i * sizeof(struct ospf_lsreq_header);
pkt->length = htons(length);
OSPF_PACKET(ospf_dump_lsreq, pkt, "LSREQ packet sent to nbr %R on %s", n->rid, ifa->ifname);
ospf_send_to_nbr(ifa, n);
}
void
ospf_receive_lsreq(struct ospf_packet *pkt, struct ospf_iface *ifa,
struct ospf_neighbor *n)
{
struct ospf_proto *p = ifa->oa->po;
struct ospf_lsreq_header *lsrs;
uint i, lsr_count;
/* RFC 2328 10.7 */
/* No need to check length, lsreq has only basic header */
OSPF_PACKET(ospf_dump_lsreq, pkt, "LSREQ packet received from nbr %R on %s", n->rid, ifa->ifname);
if (n->state < NEIGHBOR_EXCHANGE)
{
OSPF_TRACE(D_PACKETS, "LSREQ packet ignored - lesser state than Exchange");
return;
}
ospf_neigh_sm(n, INM_HELLOREC); /* Not in RFC */
ospf_lsreq_body(p, pkt, &lsrs, &lsr_count);
struct top_hash_entry *en, *entries[lsr_count];
for (i = 0; i < lsr_count; i++)
{
u32 id, rt, type, domain;
id = ntohl(lsrs[i].id);
rt = ntohl(lsrs[i].rt);
lsa_get_type_domain_(ntohl(lsrs[i].type), id, ifa, &type, &domain);
DBG("Processing requested LSA: Type: %04x, Id: %R, Rt: %R\n", type, id, rt);
en = ospf_hash_find(p->gr, domain, id, rt, type);
if (!en)
{
LOG_LSA1("Bad LSR (Type: %04x, Id: %R, Rt: %R) in LSREQ", type, id, rt);
LOG_LSA2(" received from nbr %R on %s - LSA is missing", n->rid, ifa->ifname);
ospf_neigh_sm(n, INM_BADLSREQ);
return;
}
entries[i] = en;
}
ospf_send_lsupd(p, entries, lsr_count, n);
}