| /* |
| * Copyright (c) 2010, Swedish Institute of Computer Science. |
| * All rights reserved. |
| * |
| * Copyright (c) 2013, ADVANSEE - http://www.advansee.com/ |
| * Benoît Thébaudeau <benoit.thebaudeau@advansee.com> |
| * 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 |
| * MAC sequence numbers management |
| * \author |
| * Adam Dunkels <adam@sics.se> |
| * Benoît Thébaudeau <benoit.thebaudeau@advansee.com> |
| */ |
| |
| #include <string.h> |
| |
| #include <net/l2_buf.h> |
| |
| #include "contiki-net.h" |
| #include "contiki/mac/mac-sequence.h" |
| #include "contiki/packetbuf.h" |
| |
| struct seqno { |
| linkaddr_t sender; |
| uint8_t seqno; |
| }; |
| |
| #ifdef NETSTACK_CONF_MAC_SEQNO_HISTORY |
| #define MAX_SEQNOS NETSTACK_CONF_MAC_SEQNO_HISTORY |
| #else /* NETSTACK_CONF_MAC_SEQNO_HISTORY */ |
| #define MAX_SEQNOS 16 |
| #endif /* NETSTACK_CONF_MAC_SEQNO_HISTORY */ |
| static struct seqno received_seqnos[MAX_SEQNOS]; |
| |
| /*---------------------------------------------------------------------------*/ |
| int |
| mac_sequence_is_duplicate(struct net_buf *buf) |
| { |
| int i; |
| |
| /* |
| * Check for duplicate packet by comparing the sequence number of the incoming |
| * packet with the last few ones we saw. |
| */ |
| for(i = 0; i < MAX_SEQNOS; ++i) { |
| if(linkaddr_cmp(packetbuf_addr(buf, PACKETBUF_ADDR_SENDER), |
| &received_seqnos[i].sender)) { |
| if(packetbuf_attr(buf, PACKETBUF_ATTR_PACKET_ID) == received_seqnos[i].seqno) { |
| /* Duplicate packet. */ |
| return 1; |
| } |
| break; |
| } |
| } |
| return 0; |
| } |
| /*---------------------------------------------------------------------------*/ |
| void |
| mac_sequence_register_seqno(struct net_buf *buf) |
| { |
| int i, j; |
| |
| /* Locate possible previous sequence number for this address. */ |
| for(i = 0; i < MAX_SEQNOS; ++i) { |
| if(linkaddr_cmp(packetbuf_addr(buf, PACKETBUF_ADDR_SENDER), |
| &received_seqnos[i].sender)) { |
| i++; |
| break; |
| } |
| } |
| |
| /* Keep the last sequence number for each address as per 802.15.4e. */ |
| for(j = i - 1; j > 0; --j) { |
| memcpy(&received_seqnos[j], &received_seqnos[j - 1], sizeof(struct seqno)); |
| } |
| received_seqnos[0].seqno = packetbuf_attr(buf, PACKETBUF_ATTR_PACKET_ID); |
| linkaddr_copy(&received_seqnos[0].sender, |
| packetbuf_addr(buf, PACKETBUF_ADDR_SENDER)); |
| } |
| /*---------------------------------------------------------------------------*/ |