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bird/proto/ospf/dbdes.c

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/*
* BIRD -- OSPF
*
* (c) 1999--2004 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include "ospf.h"
#ifdef OSPFv2
struct ospf_dbdes_packet
{
struct ospf_packet ospf_packet;
u16 iface_mtu;
u8 options;
union imms imms; /* I, M, MS bits */
u32 ddseq;
};
#define hton_opt(X) X
#define ntoh_opt(X) X
#endif
#ifdef OSPFv3
struct ospf_dbdes_packet
{
struct ospf_packet ospf_packet;
u32 options;
u16 iface_mtu;
u8 padding;
union imms imms; /* I, M, MS bits */
u32 ddseq;
};
#define hton_opt(X) htonl(X)
#define ntoh_opt(X) ntohl(X)
#endif
static void ospf_dump_dbdes(struct proto *p, struct ospf_dbdes_packet *pkt)
{
struct ospf_packet *op = &pkt->ospf_packet;
ASSERT(op->type == DBDES_P);
ospf_dump_common(p, op);
log(L_TRACE "%s: imms %s%s%s",
p->name, pkt->imms.bit.ms ? "MS " : "",
pkt->imms.bit.m ? "M " : "",
pkt->imms.bit.i ? "I " : "" );
log(L_TRACE "%s: ddseq %u", p->name, ntohl(pkt->ddseq));
struct ospf_lsa_header *plsa = (void *) (pkt + 1);
int i, j;
j = (ntohs(op->length) - sizeof(struct ospf_dbdes_packet)) /
sizeof(struct ospf_lsa_header);
for (i = 0; i < j; i++)
ospf_dump_lsahdr(p, plsa + i);
}
/**
* ospf_dbdes_send - transmit database description packet
* @n: neighbor
* @next: whether to send a next packet in a sequence (1) or to retransmit the old one (0)
*
* Sending of a database description packet is described in 10.8 of RFC 2328.
* Reception of each packet is acknowledged in the sequence number of another.
* When I send a packet to a neighbor I keep a copy in a buffer. If the neighbor
* does not reply, I don't create a new packet but just send the content
* of the buffer.
*/
void
ospf_dbdes_send(struct ospf_neighbor *n, int next)
{
struct ospf_dbdes_packet *pkt;
struct ospf_packet *op;
struct ospf_iface *ifa = n->ifa;
struct ospf_area *oa = ifa->oa;
struct proto_ospf *po = oa->po;
struct proto *p = &po->proto;
u16 length, i, j;
/* FIXME ??? */
if ((oa->rt == NULL) || (EMPTY_LIST(po->lsal)))
update_rt_lsa(oa);
switch (n->state)
{
case NEIGHBOR_EXSTART: /* Send empty packets */
n->myimms.bit.i = 1;
pkt = (struct ospf_dbdes_packet *) (ifa->sk->tbuf);
op = (struct ospf_packet *) pkt;
ospf_pkt_fill_hdr(ifa, pkt, DBDES_P);
pkt->iface_mtu = htons(ifa->iface->mtu);
pkt->options = hton_opt(oa->options);
pkt->imms = n->myimms;
pkt->ddseq = htonl(n->dds);
length = sizeof(struct ospf_dbdes_packet);
op->length = htons(length);
OSPF_PACKET(ospf_dump_dbdes, pkt, "DBDES packet sent to %I via %s", n->ip, ifa->iface->name);
ospf_send_to(ifa, n->ip);
break;
case NEIGHBOR_EXCHANGE:
n->myimms.bit.i = 0;
if (next)
{
snode *sn;
struct ospf_lsa_header *lsa;
pkt = n->ldbdes;
op = (struct ospf_packet *) pkt;
ospf_pkt_fill_hdr(ifa, pkt, DBDES_P);
pkt->iface_mtu = htons(ifa->iface->mtu);
pkt->ddseq = htonl(n->dds);
pkt->options = hton_opt(oa->options);
j = i = (ospf_pkt_maxsize(ifa) - sizeof(struct ospf_dbdes_packet)) / sizeof(struct ospf_lsa_header); /* Number of possible lsaheaders to send */
lsa = (n->ldbdes + sizeof(struct ospf_dbdes_packet));
if (n->myimms.bit.m)
{
sn = s_get(&(n->dbsi));
DBG("Number of LSA: %d\n", j);
for (; i > 0; i--)
{
struct top_hash_entry *en= (struct top_hash_entry *) sn;
if (ospf_lsa_flooding_allowed(&en->lsa, en->domain, ifa))
{
htonlsah(&(en->lsa), lsa);
DBG("Working on: %d\n", i);
DBG("\tX%01x %-1R %-1R %p\n", en->lsa.type, en->lsa.id, en->lsa.rt, en->lsa_body);
lsa++;
}
else i++; /* No lsa added */
if (sn == STAIL(po->lsal))
{
i--;
break;
}
sn = sn->next;
}
if (sn == STAIL(po->lsal))
{
DBG("Number of LSA NOT sent: %d\n", i);
DBG("M bit unset.\n");
n->myimms.bit.m = 0; /* Unset more bit */
}
s_put(&(n->dbsi), sn);
}
pkt->imms.byte = n->myimms.byte;
length = (j - i) * sizeof(struct ospf_lsa_header) +
sizeof(struct ospf_dbdes_packet);
op->length = htons(length);
DBG("%s: DB_DES (M) prepared for %I.\n", p->name, n->ip);
}
case NEIGHBOR_LOADING:
case NEIGHBOR_FULL:
length = ntohs(((struct ospf_packet *) n->ldbdes)->length);
if (!length)
{
OSPF_TRACE(D_PACKETS, "No packet in my buffer for repeating");
ospf_neigh_sm(n, INM_KILLNBR);
return;
}
/* Copy last sent packet again */
memcpy(ifa->sk->tbuf, n->ldbdes, length);
OSPF_PACKET(ospf_dump_dbdes, (struct ospf_dbdes_packet *) ifa->sk->tbuf,
"DBDES packet sent to %I via %s", n->ip, ifa->iface->name);
ospf_send_to(ifa, n->ip);
if(n->myimms.bit.ms) tm_start(n->rxmt_timer, n->ifa->rxmtint); /* Restart timer */
if (!n->myimms.bit.ms)
{
if ((n->myimms.bit.m == 0) && (n->imms.bit.m == 0) &&
(n->state == NEIGHBOR_EXCHANGE))
{
ospf_neigh_sm(n, INM_EXDONE);
}
}
break;
default: /* Ignore it */
break;
}
}
static void
ospf_dbdes_reqladd(struct ospf_dbdes_packet *ps, struct ospf_neighbor *n)
{
struct ospf_lsa_header *plsa, lsa;
struct top_hash_entry *he, *sn;
struct ospf_area *oa = n->ifa->oa;
struct top_graph *gr = oa->po->gr;
struct ospf_packet *op;
int i, j;
op = (struct ospf_packet *) ps;
plsa = (void *) (ps + 1);
j = (ntohs(op->length) - sizeof(struct ospf_dbdes_packet)) /
sizeof(struct ospf_lsa_header);
for (i = 0; i < j; i++)
{
ntohlsah(plsa + i, &lsa);
u32 dom = ospf_lsa_domain(lsa.type, n->ifa);
if (((he = ospf_hash_find_header(gr, dom, &lsa)) == NULL) ||
(lsa_comp(&lsa, &(he->lsa)) == 1))
{
/* Is this condition necessary? */
if (ospf_hash_find_header(n->lsrqh, dom, &lsa) == NULL)
{
sn = ospf_hash_get_header(n->lsrqh, dom, &lsa);
ntohlsah(plsa + i, &(sn->lsa));
s_add_tail(&(n->lsrql), SNODE sn);
}
}
}
}
void
ospf_dbdes_receive(struct ospf_packet *ps_i, struct ospf_iface *ifa,
struct ospf_neighbor *n)
{
struct ospf_dbdes_packet *ps = (void *) ps_i;
struct proto *p = &ifa->oa->po->proto;
u32 myrid = p->cf->global->router_id;
unsigned int size = ntohs(ps->ospf_packet.length);
u32 ps_ddseq = ntohl(ps->ddseq);
u32 ps_options = ntoh_opt(ps->options);
OSPF_PACKET(ospf_dump_dbdes, ps, "DBDES packet received from %I via %s", n->ip, ifa->iface->name);
ospf_neigh_sm(n, INM_HELLOREC);
switch (n->state)
{
case NEIGHBOR_DOWN:
case NEIGHBOR_ATTEMPT:
case NEIGHBOR_2WAY:
return;
break;
case NEIGHBOR_INIT:
ospf_neigh_sm(n, INM_2WAYREC);
if (n->state != NEIGHBOR_EXSTART)
return;
case NEIGHBOR_EXSTART:
if ((ps->imms.bit.m && ps->imms.bit.ms && ps->imms.bit.i)
&& (n->rid > myrid) && (size == sizeof(struct ospf_dbdes_packet)))
{
/* I'm slave! */
n->dds = ps_ddseq;
n->ddr = ps_ddseq;
n->options = ps_options;
n->myimms.bit.ms = 0;
n->imms.byte = ps->imms.byte;
OSPF_TRACE(D_PACKETS, "I'm slave to %I.", n->ip);
ospf_neigh_sm(n, INM_NEGDONE);
ospf_dbdes_send(n, 1);
break;
}
if (((ps->imms.bit.i == 0) && (ps->imms.bit.ms == 0)) &&
(n->rid < myrid) && (n->dds == ps_ddseq))
{
/* I'm master! */
n->options = ps_options;
n->ddr = ps_ddseq - 1; /* It will be set corectly a few lines down */
n->imms.byte = ps->imms.byte;
OSPF_TRACE(D_PACKETS, "I'm master to %I.", n->ip);
ospf_neigh_sm(n, INM_NEGDONE);
}
else
{
DBG("%s: Nothing happend to %I (imms=%u)\n", p->name, n->ip,
ps->imms.byte);
break;
}
case NEIGHBOR_EXCHANGE:
if ((ps->imms.byte == n->imms.byte) && (ps_options == n->options) &&
(ps_ddseq == n->ddr))
{
/* Duplicate packet */
OSPF_TRACE(D_PACKETS, "Received duplicate dbdes from %I.", n->ip);
if (n->myimms.bit.ms == 0)
{
/* Slave should retransmit dbdes packet */
ospf_dbdes_send(n, 0);
}
return;
}
n->ddr = ps_ddseq;
if (ps->imms.bit.ms != n->imms.bit.ms) /* M/S bit differs */
{
OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (bit MS)",
n->ip);
ospf_neigh_sm(n, INM_SEQMIS);
break;
}
if (ps->imms.bit.i) /* I bit is set */
{
OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (bit I)",
n->ip);
ospf_neigh_sm(n, INM_SEQMIS);
break;
}
n->imms.byte = ps->imms.byte;
if (ps_options != n->options) /* Options differs */
{
OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (options)",
n->ip);
ospf_neigh_sm(n, INM_SEQMIS);
break;
}
if (n->myimms.bit.ms)
{
if (ps_ddseq != n->dds) /* MASTER */
{
OSPF_TRACE(D_PACKETS,
"dbdes - sequence mismatch neighbor %I (master)", n->ip);
ospf_neigh_sm(n, INM_SEQMIS);
break;
}
n->dds++;
DBG("Incrementing dds\n");
ospf_dbdes_reqladd(ps, n);
if ((n->myimms.bit.m == 0) && (ps->imms.bit.m == 0))
{
ospf_neigh_sm(n, INM_EXDONE);
}
else
{
ospf_dbdes_send(n, 1);
}
}
else
{
if (ps_ddseq != (n->dds + 1)) /* SLAVE */
{
OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (slave)",
n->ip);
ospf_neigh_sm(n, INM_SEQMIS);
break;
}
n->ddr = ps_ddseq;
n->dds = ps_ddseq;
ospf_dbdes_reqladd(ps, n);
ospf_dbdes_send(n, 1);
}
break;
case NEIGHBOR_LOADING:
case NEIGHBOR_FULL:
if ((ps->imms.byte == n->imms.byte) && (ps_options == n->options)
&& (ps_ddseq == n->ddr))
/* Only duplicate are accepted */
{
OSPF_TRACE(D_PACKETS, "Received duplicate dbdes from %I.", n->ip);
if (n->myimms.bit.ms == 0)
{
/* Slave should retransmit dbdes packet */
ospf_dbdes_send(n, 0);
}
return;
}
else
{
OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (full)",
n->ip);
DBG("PS=%u, DDR=%u, DDS=%u\n", ps_ddseq, n->ddr, n->dds);
ospf_neigh_sm(n, INM_SEQMIS);
}
break;
default:
bug("Received dbdes from %I in undefined state.", n->ip);
}
}
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