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/*
* BIRD -- BGP Packet Processing
*
* (c) 2000 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#define LOCAL_DEBUG
#include "nest/bird.h"
#include "nest/iface.h"
#include "nest/protocol.h"
#include "nest/route.h"
#include "conf/conf.h"
#include "lib/unaligned.h"
#include "lib/socket.h"
#include "bgp.h"
static byte *
bgp_create_notification(struct bgp_conn *conn, byte *buf)
{
DBG("BGP: Sending notification: code=%d, sub=%d, arg=%d:%d\n", conn->notify_code, conn->notify_subcode, conn->notify_arg, conn->notify_arg_size);
buf[0] = conn->notify_code;
buf[1] = conn->notify_subcode;
switch (conn->notify_arg_size)
{
case 1:
buf[2] = conn->notify_arg; return buf+3;
case 2:
put_u16(buf+2, conn->notify_arg); return buf+4;
case 4:
put_u32(buf+2, conn->notify_arg); return buf+6;
default:
bug("bgp_create_notification: unknown error code size");
}
}
static byte *
bgp_create_open(struct bgp_conn *conn, byte *buf)
{
DBG("BGP: Sending open\n");
buf[0] = BGP_VERSION;
put_u16(buf+1, conn->bgp->local_as);
put_u16(buf+3, conn->bgp->cf->hold_time);
put_u32(buf+5, conn->bgp->local_id);
buf[9] = 0; /* No optional parameters */
return buf+10;
}
static byte *
bgp_create_update(struct bgp_conn *conn, byte *buf)
{
DBG("BGP: Sending update\n");
bug("Don't know how to create updates");
}
static void
bgp_create_header(byte *buf, unsigned int len, unsigned int type)
{
memset(buf, 0xff, 16); /* Marker */
put_u16(buf+16, len);
buf[18] = type;
}
static void
bgp_fire_tx(struct bgp_conn *conn)
{
unsigned int s = conn->packets_to_send;
sock *sk = conn->sk;
byte *buf = sk->tbuf;
byte *pkt = buf + BGP_HEADER_LENGTH;
byte *end;
int type;
if (s & (1 << PKT_SCHEDULE_CLOSE))
{
conn->packets_to_send = 0;
bug("Scheduled close"); /* FIXME */
}
if (s & (1 << PKT_NOTIFICATION))
{
s = 1 << PKT_SCHEDULE_CLOSE;
type = PKT_NOTIFICATION;
end = bgp_create_notification(conn, pkt);
}
else if (s & (1 << PKT_KEEPALIVE))
{
s &= ~(1 << PKT_KEEPALIVE);
type = PKT_KEEPALIVE;
end = pkt; /* Keepalives carry no data */
DBG("BGP: Sending keepalive\n");
}
else if (s & (1 << PKT_OPEN))
{
s &= ~(1 << PKT_OPEN);
type = PKT_OPEN;
end = bgp_create_open(conn, pkt);
}
else if (s & (1 << PKT_UPDATE))
{
end = bgp_create_update(conn, pkt);
type = PKT_UPDATE;
if (!end)
{
conn->packets_to_send = 0;
return;
}
}
else
return;
conn->packets_to_send = s;
bgp_create_header(buf, end - buf, type);
sk_send(sk, end - buf);
}
void
bgp_schedule_packet(struct bgp_conn *conn, int type)
{
DBG("BGP: Scheduling packet type %d\n", type);
conn->packets_to_send |= 1 << type;
if (conn->sk->tpos != conn->sk->tbuf)
bgp_fire_tx(conn);
}
void
bgp_tx(sock *sk)
{
struct bgp_conn *conn = sk->data;
DBG("BGP: TX hook\n");
bgp_fire_tx(conn);
}
int
bgp_rx(sock *sk, int size)
{
struct bgp_conn *conn = sk->data;
byte *pkt_start = sk->rbuf;
byte *end = pkt_start + size;
DBG("BGP: RX hook: Got %d bytes\n", size);
while (end >= pkt_start + BGP_HEADER_LENGTH)
{
if (conn->error_flag)
return 1;
bug("Incoming packets not handled"); /* FIXME */
}
if (pkt_start != sk->rbuf)
{
memmove(sk->rbuf, pkt_start, end - pkt_start);
sk->rpos = sk->rbuf + (end - pkt_start);
}
return 0;
}
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