freebsd-src/sys/dev/wtap/if_medium.c
Adrian Chadd 04d1980289 Introduce wtap, the beginnings of a net80211 wlan simulator.
This introduces:

* a basic wtap interface
* a HAL, which implements an abstraction layer for implementing
  different device behavious;
* A visibility plugin, which allows for control over which nodes
  see other nodes (useful for mesh work.)

It doesn't yet implement sta/adhoc/hostap modes but these are quite
feasible to implement.

Monthadar uses it to do 802.11s mesh verification.

The userland tools will be committed in a follow-up commit.

Submitted by:	Monthadar Al Jaberi <monthadar@gmail.com>
2012-01-11 17:41:14 +00:00

121 lines
3.3 KiB
C

/*-
* Copyright (c) 2010-2011 Monthadar Al Jaberi, TerraNet AB
* 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,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
* redistribution must be conditioned upon including a substantially
* similar Disclaimer requirement for further binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES.
*
* $FreeBSD$
*/
#include "if_wtapvar.h"
#include "if_medium.h"
void
init_medium(struct wtap_medium *md)
{
DWTAP_PRINTF("%s\n", __func__);
STAILQ_INIT(&md->md_pktbuf);
mtx_init(&md->md_mtx, "wtap_medium mtx", NULL, MTX_DEF | MTX_RECURSE);
/* Event handler for sending packets between wtaps */
struct eventhandler *eh = (struct eventhandler *)
malloc(sizeof(struct eventhandler), M_WTAP, M_NOWAIT | M_ZERO);
eh->tq = taskqueue_create("wtap_tx_taskq", M_NOWAIT | M_ZERO,
taskqueue_thread_enqueue, &eh->tq);
taskqueue_start_threads(&eh->tq, 1, PI_NET, "%s taskq", "wtap_medium");
md->tx_handler = eh;
/* Mark medium closed by default */
md->open = 0;
}
void
deinit_medium(struct wtap_medium *md)
{
DWTAP_PRINTF("%s\n", __func__);
taskqueue_free(md->tx_handler->tq);
free(md->tx_handler, M_WTAP);
}
int
medium_transmit(struct wtap_medium *md, int id, struct mbuf*m)
{
mtx_lock(&md->md_mtx);
if (md->open == 0){
DWTAP_PRINTF("[%d] dropping m=%p\n", id, m);
m_free(m);
mtx_unlock(&md->md_mtx);
return 0;
}
DWTAP_PRINTF("[%d] transmiting m=%p\n", id, m);
struct packet *p = (struct packet *)malloc(sizeof(struct packet),
M_WTAP_PACKET, M_ZERO | M_NOWAIT);
p->id = id;
p->m = m;
STAILQ_INSERT_TAIL(&md->md_pktbuf, p, pf_list);
taskqueue_enqueue(md->tx_handler->tq, &md->tx_handler->proc);
mtx_unlock(&md->md_mtx);
return 0;
}
struct packet *
medium_get_next_packet(struct wtap_medium *md)
{
struct packet *p;
mtx_lock(&md->md_mtx);
p = STAILQ_FIRST(&md->md_pktbuf);
if (p == NULL){
mtx_unlock(&md->md_mtx);
return NULL;
}
STAILQ_REMOVE_HEAD(&md->md_pktbuf, pf_list);
mtx_unlock(&md->md_mtx);
return p;
}
void
medium_open(struct wtap_medium *md)
{
mtx_lock(&md->md_mtx);
md->open = 1;
mtx_unlock(&md->md_mtx);
}
void
medium_close(struct wtap_medium *md)
{
mtx_lock(&md->md_mtx);
md->open = 0;
mtx_unlock(&md->md_mtx);
}