nes-proj/core/net/rpl/rpl-ext-header.c

316 lines
11 KiB
C

/**
* \addtogroup uip6
* @{
*/
/*
* Copyright (c) 2009, Swedish Institute of Computer Science.
* 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
* Management of extension headers for ContikiRPL.
*
* \author Vincent Brillault <vincent.brillault@imag.fr>,
* Joakim Eriksson <joakime@sics.se>,
* Niclas Finne <nfi@sics.se>,
* Nicolas Tsiftes <nvt@sics.se>.
*/
#include "net/uip.h"
#include "net/tcpip.h"
#include "net/uip-ds6.h"
#include "net/rpl/rpl-private.h"
#define DEBUG DEBUG_NONE
#include "net/uip-debug.h"
#include <limits.h>
#include <string.h>
/*---------------------------------------------------------------------------*/
#define UIP_IP_BUF ((struct uip_ip_hdr *)&uip_buf[UIP_LLH_LEN])
#define UIP_EXT_BUF ((struct uip_ext_hdr *)&uip_buf[uip_l2_l3_hdr_len])
#define UIP_HBHO_BUF ((struct uip_hbho_hdr *)&uip_buf[uip_l2_l3_hdr_len])
#define UIP_HBHO_NEXT_BUF ((struct uip_ext_hdr *)&uip_buf[uip_l2_l3_hdr_len + RPL_HOP_BY_HOP_LEN])
#define UIP_EXT_HDR_OPT_BUF ((struct uip_ext_hdr_opt *)&uip_buf[uip_l2_l3_hdr_len + uip_ext_opt_offset])
#define UIP_EXT_HDR_OPT_PADN_BUF ((struct uip_ext_hdr_opt_padn *)&uip_buf[uip_l2_l3_hdr_len + uip_ext_opt_offset])
#define UIP_EXT_HDR_OPT_RPL_BUF ((struct uip_ext_hdr_opt_rpl *)&uip_buf[uip_l2_l3_hdr_len + uip_ext_opt_offset])
/*---------------------------------------------------------------------------*/
int
rpl_verify_header(int uip_ext_opt_offset)
{
rpl_instance_t *instance;
int down;
uint8_t sender_closer;
if(UIP_EXT_HDR_OPT_RPL_BUF->opt_len != RPL_HDR_OPT_LEN) {
PRINTF("RPL: Bad header option! (wrong length)\n");
return 1;
}
if(UIP_EXT_HDR_OPT_RPL_BUF->flags & RPL_HDR_OPT_FWD_ERR) {
PRINTF("RPL: Forward error!\n");
/* We should try to repair it, not implemented for the moment */
return 2;
}
instance = rpl_get_instance(UIP_EXT_HDR_OPT_RPL_BUF->instance);
if(instance == NULL) {
PRINTF("RPL: Unknown instance: %u\n",
UIP_EXT_HDR_OPT_RPL_BUF->instance);
return 1;
}
if(!instance->current_dag->joined) {
PRINTF("RPL: No DAG in the instance\n");
return 1;
}
down = 0;
if(UIP_EXT_HDR_OPT_RPL_BUF->flags & RPL_HDR_OPT_DOWN) {
down = 1;
}
sender_closer = UIP_EXT_HDR_OPT_RPL_BUF->senderrank < instance->current_dag->rank;
PRINTF("RPL: Packet going %s, sender closer %d (%d < %d)\n", down == 1 ? "down" : "up",
sender_closer,
UIP_EXT_HDR_OPT_RPL_BUF->senderrank,
instance->current_dag->rank
);
if((down && !sender_closer) || (!down && sender_closer)) {
PRINTF("RPL: Loop detected - senderrank: %d my-rank: %d sender_closer: %d\n",
UIP_EXT_HDR_OPT_RPL_BUF->senderrank, instance->current_dag->rank,
sender_closer);
if(UIP_EXT_HDR_OPT_RPL_BUF->flags & RPL_HDR_OPT_RANK_ERR) {
PRINTF("RPL: Rank error signalled in RPL option!\n");
/* We should try to repair it, not implemented for the moment */
return 3;
}
PRINTF("RPL: Single error tolerated\n");
UIP_EXT_HDR_OPT_RPL_BUF->flags |= RPL_HDR_OPT_RANK_ERR;
return 0;
}
PRINTF("RPL: Rank OK\n");
return 0;
}
/*---------------------------------------------------------------------------*/
static void
set_rpl_opt(unsigned uip_ext_opt_offset)
{
uint8_t temp_len;
memmove(UIP_HBHO_NEXT_BUF, UIP_EXT_BUF, uip_len - UIP_IPH_LEN);
memset(UIP_HBHO_BUF, 0, RPL_HOP_BY_HOP_LEN);
UIP_HBHO_BUF->next = UIP_IP_BUF->proto;
UIP_IP_BUF->proto = UIP_PROTO_HBHO;
UIP_HBHO_BUF->len = RPL_HOP_BY_HOP_LEN - 8;
UIP_EXT_HDR_OPT_RPL_BUF->opt_type = UIP_EXT_HDR_OPT_RPL;
UIP_EXT_HDR_OPT_RPL_BUF->opt_len = RPL_HDR_OPT_LEN;
UIP_EXT_HDR_OPT_RPL_BUF->flags = 0;
UIP_EXT_HDR_OPT_RPL_BUF->instance = 0;
UIP_EXT_HDR_OPT_RPL_BUF->senderrank = 0;
uip_len += RPL_HOP_BY_HOP_LEN;
temp_len = UIP_IP_BUF->len[1];
UIP_IP_BUF->len[1] += UIP_HBHO_BUF->len + 8;
if(UIP_IP_BUF->len[1] < temp_len) {
UIP_IP_BUF->len[0]++;
}
}
/*---------------------------------------------------------------------------*/
void
rpl_update_header_empty(void)
{
rpl_instance_t *instance;
int uip_ext_opt_offset;
int last_uip_ext_len;
last_uip_ext_len = uip_ext_len;
uip_ext_len = 0;
uip_ext_opt_offset = 2;
PRINTF("RPL: Verifying the presence of the RPL header option\n");
switch(UIP_IP_BUF->proto) {
case UIP_PROTO_HBHO:
if(UIP_HBHO_BUF->len != RPL_HOP_BY_HOP_LEN - 8) {
PRINTF("RPL: Non RPL Hop-by-hop options support not implemented\n");
uip_ext_len = last_uip_ext_len;
return;
}
instance = rpl_get_instance(UIP_EXT_HDR_OPT_RPL_BUF->instance);
if(instance == NULL || !instance->used || !instance->current_dag->joined) {
PRINTF("RPL: Unable to add hop-by-hop extension header: incorrect instance\n");
return;
}
break;
default:
PRINTF("RPL: No hop-by-hop option found, creating it\n");
if(uip_len + RPL_HOP_BY_HOP_LEN > UIP_BUFSIZE) {
PRINTF("RPL: Packet too long: impossible to add hop-by-hop option\n");
uip_ext_len = last_uip_ext_len;
return;
}
set_rpl_opt(uip_ext_opt_offset);
uip_ext_len = last_uip_ext_len + RPL_HOP_BY_HOP_LEN;
return;
}
switch(UIP_EXT_HDR_OPT_BUF->type) {
case UIP_EXT_HDR_OPT_RPL:
PRINTF("RPL: Updating RPL option\n");
UIP_EXT_HDR_OPT_RPL_BUF->senderrank = instance->current_dag->rank;
/* Set the down extension flag correctly as described in Section
11.2 of RFC6550. If the packet progresses along a DAO route,
the down flag should be set. */
if(uip_ds6_route_lookup(&UIP_IP_BUF->destipaddr) == NULL) {
/* No route was found, so this packet will go towards the RPL
root. If so, we should not set the down flag. */
UIP_EXT_HDR_OPT_RPL_BUF->flags &= ~RPL_HDR_OPT_DOWN;
} else {
/* A DAO route was found so we set the down flag. */
UIP_EXT_HDR_OPT_RPL_BUF->flags |= RPL_HDR_OPT_DOWN;
}
uip_ext_len = last_uip_ext_len;
return;
default:
PRINTF("RPL: Multi Hop-by-hop options not implemented\n");
uip_ext_len = last_uip_ext_len;
return;
}
}
/*---------------------------------------------------------------------------*/
int
rpl_update_header_final(uip_ipaddr_t *addr)
{
rpl_parent_t *parent;
int uip_ext_opt_offset;
int last_uip_ext_len;
last_uip_ext_len = uip_ext_len;
uip_ext_len = 0;
uip_ext_opt_offset = 2;
if(UIP_IP_BUF->proto == UIP_PROTO_HBHO) {
if(UIP_HBHO_BUF->len != RPL_HOP_BY_HOP_LEN - 8) {
PRINTF("RPL: Non RPL Hop-by-hop options support not implemented\n");
uip_ext_len = last_uip_ext_len;
return 0;
}
if(UIP_EXT_HDR_OPT_BUF->type == UIP_EXT_HDR_OPT_RPL) {
if(UIP_EXT_HDR_OPT_RPL_BUF->senderrank == 0) {
PRINTF("RPL: Updating RPL option\n");
if(default_instance == NULL || !default_instance->used || !default_instance->current_dag->joined) {
PRINTF("RPL: Unable to add hop-by-hop extension header: incorrect default instance\n");
return 1;
}
parent = rpl_find_parent(default_instance->current_dag, addr);
if(parent == NULL || parent != parent->dag->preferred_parent) {
UIP_EXT_HDR_OPT_RPL_BUF->flags = RPL_HDR_OPT_DOWN;
}
UIP_EXT_HDR_OPT_RPL_BUF->instance = default_instance->instance_id;
UIP_EXT_HDR_OPT_RPL_BUF->senderrank = default_instance->current_dag->rank;
uip_ext_len = last_uip_ext_len;
}
}
}
return 0;
}
/*---------------------------------------------------------------------------*/
void
rpl_remove_header(void)
{
int last_uip_ext_len;
uint8_t temp_len;
last_uip_ext_len = uip_ext_len;
uip_ext_len = 0;
PRINTF("RPL: Verifying the presence of the RPL header option\n");
switch(UIP_IP_BUF->proto){
case UIP_PROTO_HBHO:
PRINTF("RPL: Removing the RPL header option\n");
UIP_IP_BUF->proto = UIP_HBHO_BUF->next;
temp_len = UIP_IP_BUF->len[1];
uip_len -= UIP_HBHO_BUF->len + 8;
UIP_IP_BUF->len[1] -= UIP_HBHO_BUF->len + 8;
if(UIP_IP_BUF->len[1] > temp_len) {
UIP_IP_BUF->len[0]--;
}
memmove(UIP_EXT_BUF, UIP_HBHO_NEXT_BUF, uip_len - UIP_IPH_LEN);
break;
default:
PRINTF("RPL: No hop-by-hop Option found\n");
}
}
/*---------------------------------------------------------------------------*/
uint8_t
rpl_invert_header(void)
{
uint8_t uip_ext_opt_offset;
uint8_t last_uip_ext_len;
last_uip_ext_len = uip_ext_len;
uip_ext_len = 0;
uip_ext_opt_offset = 2;
PRINTF("RPL: Verifying the presence of the RPL header option\n");
switch(UIP_IP_BUF->proto) {
case UIP_PROTO_HBHO:
break;
default:
PRINTF("RPL: No hop-by-hop Option found\n");
uip_ext_len = last_uip_ext_len;
return 0;
}
switch (UIP_EXT_HDR_OPT_BUF->type) {
case UIP_EXT_HDR_OPT_RPL:
PRINTF("RPL: Updating RPL option (switching direction)\n");
UIP_EXT_HDR_OPT_RPL_BUF->flags &= RPL_HDR_OPT_DOWN;
UIP_EXT_HDR_OPT_RPL_BUF->flags ^= RPL_HDR_OPT_DOWN;
UIP_EXT_HDR_OPT_RPL_BUF->senderrank = rpl_get_instance(UIP_EXT_HDR_OPT_RPL_BUF->instance)->current_dag->rank;
uip_ext_len = last_uip_ext_len;
return RPL_HOP_BY_HOP_LEN;
default:
PRINTF("RPL: Multi Hop-by-hop options not implemented\n");
uip_ext_len = last_uip_ext_len;
return 0;
}
}
/*---------------------------------------------------------------------------*/