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/* $OpenBSD: transport.c,v 1.2 1998/11/15 00:44:03 niklas Exp $ */
/*
* Copyright (c) 1998 Niklas Hallqvist. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Ericsson Radio Systems.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This code was written under funding by Ericsson Radio Systems.
*/
#include <sys/param.h>
#include <sys/queue.h>
#include "conf.h"
#include "exchange.h"
#include "log.h"
#include "message.h"
#include "sa.h"
#include "timer.h"
#include "transport.h"
LIST_HEAD (transport_list, transport) transport_list;
LIST_HEAD (transport_method_list, transport_vtbl) transport_method_list;
/* Initialize the transport maintenance module. */
void
transport_init (void)
{
LIST_INIT (&transport_list);
LIST_INIT (&transport_method_list);
}
/* Register another transport T. */
void
transport_add (struct transport *t)
{
TAILQ_INIT (&t->sendq);
LIST_INSERT_HEAD (&transport_list, t, link);
}
/* Register another transport method T. */
void
transport_method_add (struct transport_vtbl *t)
{
LIST_INSERT_HEAD (&transport_method_list, t, link);
}
/* Apply a function FUNC on all registered transports. */
void
transport_map (void (*func) (struct transport *))
{
struct transport *t;
for (t = LIST_FIRST (&transport_list); t; t = LIST_NEXT (t, link))
(*func) (t);
}
/*
* Build up a file desciptor set FDS with all transport descriptors we want
* to read from. Return the number of file descriptors select(2) needs to
* check in order to cover the ones we setup in here.
*/
int
transport_fd_set (fd_set *fds)
{
int n;
int max = -1;
struct transport *t;
for (t = LIST_FIRST (&transport_list); t; t = LIST_NEXT (t, link))
if (t->flags & TRANSPORT_LISTEN)
{
n = (*t->vtbl->fd_set) (t, fds);
if (n > max)
max = n;
}
return max + 1;
}
/*
* Build up a file desciptor set FDS with all the descriptors belonging to
* transport where messages are queued for transmittal. Return the number
* of file descriptors select(2) needs to check in order to cover the ones
* we setup in here.
*/
int
transport_pending_wfd_set (fd_set *fds)
{
int n;
int max = -1;
struct transport *t;
for (t = LIST_FIRST (&transport_list); t; t = LIST_NEXT (t, link))
{
if (TAILQ_FIRST (&t->sendq))
{
n = (*t->vtbl->fd_set) (t, fds);
if (n > max)
max = n;
}
}
return max + 1;
}
/*
* For each transport with a file descriptor in FDS, try to get an
* incoming message and start processing it.
*/
void
transport_handle_messages (fd_set *fds)
{
struct transport *t;
for (t = LIST_FIRST (&transport_list); t; t = LIST_NEXT (t, link))
if ((t->flags & TRANSPORT_LISTEN) && (*t->vtbl->fd_isset) (t, fds))
(*t->vtbl->handle_message) (t);
}
/*
* Send the first queued message on the transports whose file descriptor
* is in FDS.
*/
void
transport_send_messages (fd_set *fds)
{
struct transport *t;
struct message *msg;
struct timeval expiration;
struct sa *sa, *next_sa;
int expiry;
for (t = LIST_FIRST (&transport_list); t; t = LIST_NEXT (t, link))
if (TAILQ_FIRST (&t->sendq) && (*t->vtbl->fd_isset) (t, fds))
{
msg = TAILQ_FIRST (&t->sendq);
TAILQ_REMOVE (&t->sendq, msg, link);
/*
* We disregard the potential error message here, hoping that the
* retransmit will go better.
* XXX Consider a retry/fatal error discriminator.
*/
t->vtbl->send_message (msg);
/*
* If this is not a retransmit call post-send functions that allows
* parallel work to be done while the network and peer does their
* share of the job.
*/
if (msg->xmits == 0)
message_post_send (msg);
msg->xmits++;
if ((msg->flags & MSG_NO_RETRANS) == 0)
{
/* XXX make this a configurable parameter. */
if (msg->xmits > conf_get_num ("General", "retransmits"))
{
log_print ("transport_send_messages: giving up on message %p",
msg);
msg->exchange->last_sent = 0;
/*
* As this exchange never went to a normal end, remove the
* SA's being negotiated too.
*/
for (sa = TAILQ_FIRST (&msg->exchange->sa_list); sa;
sa = next_sa)
{
next_sa = TAILQ_NEXT (sa, next);
sa_free (sa);
}
exchange_free (msg->exchange);
message_free (msg);
return;
};
gettimeofday (&expiration, 0);
/* XXX Calculate from round trip timings and a backoff func. */
expiry = msg->xmits * 2 + 5;
expiration.tv_sec += expiry;
log_debug (LOG_TRANSPORT, 30,
"transport_send_messages: "
"message %p scheduled for retransmission %d in %d secs",
msg, msg->xmits, expiry);
msg->retrans = timer_add_event ("message_send",
(void (*) (void *))message_send,
msg, &expiration);
if (!msg->retrans)
{
/* If we can make no retransmission, we can't.... */
message_free (msg);
return;
}
msg->exchange->last_sent = msg;
}
else if ((msg->flags & MSG_KEEP) == 0)
message_free (msg);
}
}
/*
* Textual search after the transport method denoted by NAME, then create
* a transport connected to the peer with address ADDR, given in a transport-
* specific string format.
*/
struct transport *
transport_create (char *name, char *addr)
{
struct transport_vtbl *method;
for (method = LIST_FIRST (&transport_method_list); method;
method = LIST_NEXT (method, link))
if (strcmp (method->name, name) == 0)
return (*method->create) (addr);
return 0;
}
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