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/*
* BIRD -- OSPF
*
* (c) 1999 - 2003 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include "ospf.h"
void
fill_ospf_pkt_hdr(struct ospf_iface *ifa, void *buf, u8 h_type)
{
struct ospf_packet *pkt;
struct proto *p;
p = (struct proto *) (ifa->proto);
pkt = (struct ospf_packet *) buf;
pkt->version = OSPF_VERSION;
pkt->type = h_type;
pkt->routerid = htonl(p->cf->global->router_id);
pkt->areaid = htonl(ifa->an);
pkt->autype = htons(ifa->autype);
pkt->checksum = 0;
}
void
ospf_tx_authenticate(struct ospf_iface *ifa, struct ospf_packet *pkt)
{
pkt->autype = htons(ifa->autype);
memcpy(pkt->authetication, ifa->aukey, 8);
return;
}
static int
ospf_rx_authenticate(struct ospf_iface *ifa, struct ospf_packet *pkt)
{
int i;
if (pkt->autype != htons(ifa->autype))
return 0;
if (ifa->autype == AU_NONE)
return 1;
if (ifa->autype == AU_SIMPLE)
{
for (i = 0; i < 8; i++)
{
if (pkt->authetication[i] != ifa->aukey[i])
return 0;
}
return 1;
}
return 0;
}
void
ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt)
{
ospf_tx_authenticate(ifa, pkt);
/* Count checksum */
pkt->checksum = ipsum_calculate(pkt, sizeof(struct ospf_packet) - 8,
(pkt + 1),
ntohs(pkt->length) -
sizeof(struct ospf_packet), NULL);
}
/**
* ospf_rx_hook
* @sk: socket we received the packet. Its ignored.
* @size: size of the packet
*
* This is the entry point for messages from neighbors. Many checks (like
* authentication, checksums, size) are done before the packet is passed to
* non generic functions.
*/
int
ospf_rx_hook(sock * sk, int size)
{
struct ospf_packet *ps;
struct ospf_iface *ifa = (struct ospf_iface *) (sk->data);
struct proto *p = (struct proto *) (ifa->proto);
if (ifa->stub)
return (1);
DBG("%s: RX_Hook called on interface %s.\n", p->name, sk->iface->name);
ps = (struct ospf_packet *) ipv4_skip_header(sk->rbuf, &size);
if (ps == NULL)
{
log("%s: Bad OSPF packet received: bad IP header", p->name);
log("%s: Discarding", p->name);
return (1);
}
if ((unsigned) size < sizeof(struct ospf_packet))
{
log("%s: Bad OSPF packet received: too short (%u bytes)", p->name, size);
log("%s: Discarding", p->name);
return (1);
}
if ((ntohs(ps->length) != size) || (size != (4 * (size / 4))))
{
log("%s: Bad OSPF packet received: size field does not match", p->name);
log("%s: Discarding", p->name);
return (1);
}
if (ps->version != OSPF_VERSION)
{
log("%s: Bad OSPF packet received: version %u", p->name, ps->version);
log("%s: Discarding", p->name);
return (1);
}
if (!ipsum_verify(ps, 16, (void *) ps + sizeof(struct ospf_packet),
ntohs(ps->length) - sizeof(struct ospf_packet), NULL))
{
log("%s: Bad OSPF packet received: bad checksum", p->name);
log("%s: Discarding", p->name);
return (1);
}
if (!ospf_rx_authenticate(ifa, ps))
{
log("%s: Bad OSPF packet received: bad password", p->name);
return (1);
}
if (ntohl(ps->areaid) != ifa->an)
{
log("%s: Bad OSPF packet received: other area %ld", p->name, ps->areaid);
log("%s: Discarding", p->name);
return (1);
}
if (ntohl(ps->routerid) == p->cf->global->router_id)
{
log("%s: Bad OSPF packet received: received my own router ID!", p->name);
log("%s: Discarding", p->name);
return (1);
}
if (ntohl(ps->routerid) == 0)
{
log("%s: Bad OSPF packet received: Id 0.0.0.0 is not allowed.", p->name);
log("%s: Discarding", p->name);
return (1);
}
/* Dump packet
pu8=(u8 *)(sk->rbuf+5*4);
for(i=0;i<ntohs(ps->length);i+=4)
DBG("%s: received %u,%u,%u,%u\n",p->name, pu8[i+0], pu8[i+1], pu8[i+2],
pu8[i+3]);
DBG("%s: received size: %u\n",p->name,size);
*/
switch (ps->type)
{
case HELLO_P:
DBG("%s: Hello received.\n", p->name);
ospf_hello_receive((struct ospf_hello_packet *) ps, ifa, size, sk->faddr);
break;
case DBDES_P:
DBG("%s: Database description received.\n", p->name);
ospf_dbdes_receive((struct ospf_dbdes_packet *) ps, ifa, size);
break;
case LSREQ_P:
DBG("%s: Link state request received.\n", p->name);
ospf_lsreq_receive((struct ospf_lsreq_packet *) ps, ifa, size);
break;
case LSUPD_P:
DBG("%s: Link state update received.\n", p->name);
ospf_lsupd_receive((struct ospf_lsupd_packet *) ps, ifa, size);
break;
case LSACK_P:
DBG("%s: Link state ack received.\n", p->name);
ospf_lsack_receive((struct ospf_lsack_packet *) ps, ifa, size);
break;
default:
log("%s: Bad packet received: wrong type %u", p->name, ps->type);
log("%s: Discarding\n", p->name);
return (1);
};
return (1);
}
void
ospf_tx_hook(sock * sk)
{
struct ospf_iface *ifa;
struct proto *p;
ifa = (struct ospf_iface *) (sk->data);
p = (struct proto *) (ifa->proto);
DBG("%s: TX_Hook called on interface %s\n", p->name, sk->iface->name);
}
void
ospf_err_hook(sock * sk, int err UNUSED)
{
struct ospf_iface *ifa;
struct proto *p;
ifa = (struct ospf_iface *) (sk->data);
p = (struct proto *) (ifa->proto);
DBG("%s: Err_Hook called on interface %s\n", p->name, sk->iface->name);
}
void
sk_send_to_agt(sock * sk, u16 len, struct ospf_iface *ifa, u8 state)
{
struct ospf_neighbor *n;
WALK_LIST(NODE n, ifa->neigh_list) if (n->state >= state)
sk_send_to(sk, len, n->ip, OSPF_PROTO);
}
void
sk_send_to_bdr(sock * sk, u16 len, struct ospf_iface *ifa)
{
if (ipa_compare(ifa->drip, ipa_from_u32(0)) != 0)
sk_send_to(sk, len, ifa->drip, OSPF_PROTO);
if (ipa_compare(ifa->bdrip, ipa_from_u32(0)) != 0)
sk_send_to(sk, len, ifa->bdrip, OSPF_PROTO);
}
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