112 lines
3.7 KiB
C
112 lines
3.7 KiB
C
/*
|
|
* Copyright (c) 2014, Hasso-Plattner-Institut.
|
|
* 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. Neither the name of the Institute nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE OR CONTRIBUTORS 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 file is part of the Contiki operating system.
|
|
*
|
|
*/
|
|
|
|
/**
|
|
* \file
|
|
* Protects against replay attacks by comparing with the last
|
|
* unicast or broadcast frame counter of the sender.
|
|
* \author
|
|
* Konrad Krentz <konrad.krentz@gmail.com>
|
|
*/
|
|
|
|
/**
|
|
* \addtogroup llsec802154
|
|
* @{
|
|
*/
|
|
|
|
#include "net/llsec/anti-replay.h"
|
|
#include "net/packetbuf.h"
|
|
|
|
/* This node's current frame counter value */
|
|
static uint32_t counter;
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void
|
|
anti_replay_set_counter(void)
|
|
{
|
|
frame802154_frame_counter_t reordered_counter;
|
|
|
|
++counter;
|
|
reordered_counter.u32 = LLSEC802154_HTONL(counter);
|
|
|
|
packetbuf_set_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1, reordered_counter.u16[0]);
|
|
packetbuf_set_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3, reordered_counter.u16[1]);
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
uint32_t
|
|
anti_replay_get_counter(void)
|
|
{
|
|
frame802154_frame_counter_t disordered_counter;
|
|
|
|
disordered_counter.u16[0] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_0_1);
|
|
disordered_counter.u16[1] = packetbuf_attr(PACKETBUF_ATTR_FRAME_COUNTER_BYTES_2_3);
|
|
|
|
return LLSEC802154_HTONL(disordered_counter.u32);
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
void
|
|
anti_replay_init_info(struct anti_replay_info *info)
|
|
{
|
|
info->last_broadcast_counter
|
|
= info->last_unicast_counter
|
|
= anti_replay_get_counter();
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
int
|
|
anti_replay_was_replayed(struct anti_replay_info *info)
|
|
{
|
|
uint32_t received_counter;
|
|
|
|
received_counter = anti_replay_get_counter();
|
|
|
|
if(packetbuf_holds_broadcast()) {
|
|
/* broadcast */
|
|
if(received_counter <= info->last_broadcast_counter) {
|
|
return 1;
|
|
} else {
|
|
info->last_broadcast_counter = received_counter;
|
|
return 0;
|
|
}
|
|
} else {
|
|
/* unicast */
|
|
if(received_counter <= info->last_unicast_counter) {
|
|
return 1;
|
|
} else {
|
|
info->last_unicast_counter = received_counter;
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/** @} */
|