| /* |
| * 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>. |
| */ |
| |
| /** |
| * \addtogroup uip6 |
| * @{ |
| */ |
| |
| #include <net/ip_buf.h> |
| |
| #include "contiki/ip/uip.h" |
| #include "contiki/ip/tcpip.h" |
| #include "contiki/ipv6/uip-ds6.h" |
| #include "contiki/rpl/rpl-private.h" |
| #include "contiki/packetbuf.h" |
| |
| #ifdef CONFIG_NETWORK_IP_STACK_DEBUG_RPL_ICMPV6 |
| #define DEBUG 1 |
| #endif |
| #include "contiki/ip/uip-debug.h" |
| |
| #include <limits.h> |
| #include <string.h> |
| |
| /*---------------------------------------------------------------------------*/ |
| #define UIP_IP_BUF(buf) ((struct uip_ip_hdr *)&uip_buf(buf)[UIP_LLH_LEN]) |
| #define UIP_EXT_BUF(buf) ((struct uip_ext_hdr *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf)]) |
| #define UIP_HBHO_BUF(buf) ((struct uip_hbho_hdr *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf)]) |
| #define UIP_HBHO_NEXT_BUF(buf) ((struct uip_ext_hdr *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf) + RPL_HOP_BY_HOP_LEN]) |
| #define UIP_EXT_HDR_OPT_BUF(buf) ((struct uip_ext_hdr_opt *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf) + uip_ext_opt_offset]) |
| #define UIP_EXT_HDR_OPT_PADN_BUF(buf) ((struct uip_ext_hdr_opt_padn *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf) + uip_ext_opt_offset]) |
| #define UIP_EXT_HDR_OPT_RPL_BUF(buf) ((struct uip_ext_hdr_opt_rpl *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf) + uip_ext_opt_offset]) |
| /*---------------------------------------------------------------------------*/ |
| int |
| rpl_verify_header(struct net_buf *buf, int uip_ext_opt_offset) |
| { |
| rpl_instance_t *instance; |
| int down; |
| uint16_t sender_rank; |
| uint8_t sender_closer; |
| uip_ds6_route_t *route; |
| |
| if(UIP_HBHO_BUF(buf)->len != RPL_HOP_BY_HOP_LEN - 8) { |
| PRINTF("RPL: Hop-by-hop extension header has wrong size\n"); |
| return 1; |
| } |
| |
| if(UIP_EXT_HDR_OPT_RPL_BUF(buf)->opt_type != UIP_EXT_HDR_OPT_RPL) { |
| PRINTF("RPL: Non RPL Hop-by-hop option\n"); |
| return 1; |
| } |
| |
| if(UIP_EXT_HDR_OPT_RPL_BUF(buf)->opt_len != RPL_HDR_OPT_LEN) { |
| PRINTF("RPL: Bad header option! (wrong length)\n"); |
| return 1; |
| } |
| |
| instance = rpl_get_instance(UIP_EXT_HDR_OPT_RPL_BUF(buf)->instance); |
| if(instance == NULL) { |
| PRINTF("RPL: Unknown instance: %u\n", |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->instance); |
| return 1; |
| } |
| |
| if(UIP_EXT_HDR_OPT_RPL_BUF(buf)->flags & RPL_HDR_OPT_FWD_ERR) { |
| PRINTF("RPL: Forward error!\n"); |
| /* We should try to repair it by removing the neighbor that caused |
| the packet to be forwareded in the first place. We drop any |
| routes that go through the neighbor that sent the packet to |
| us. */ |
| route = uip_ds6_route_lookup(&UIP_IP_BUF(buf)->destipaddr); |
| if(route != NULL) { |
| uip_ds6_route_rm(route); |
| } |
| RPL_STAT(rpl_stats.forward_errors++); |
| /* Trigger DAO retransmission */ |
| rpl_reset_dio_timer(instance); |
| /* drop the packet as it is not routable */ |
| 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(buf)->flags & RPL_HDR_OPT_DOWN) { |
| down = 1; |
| } |
| |
| sender_rank = UIP_HTONS(UIP_EXT_HDR_OPT_RPL_BUF(buf)->senderrank); |
| sender_closer = sender_rank < instance->current_dag->rank; |
| |
| PRINTF("RPL: Packet going %s, sender closer %d (%d < %d)\n", down == 1 ? "down" : "up", |
| sender_closer, |
| sender_rank, |
| instance->current_dag->rank |
| ); |
| |
| if((down && !sender_closer) || (!down && sender_closer)) { |
| PRINTF("RPL: Loop detected - senderrank: %d my-rank: %d sender_closer: %d\n", |
| sender_rank, instance->current_dag->rank, |
| sender_closer); |
| if(UIP_EXT_HDR_OPT_RPL_BUF(buf)->flags & RPL_HDR_OPT_RANK_ERR) { |
| RPL_STAT(rpl_stats.loop_errors++); |
| PRINTF("RPL: Rank error signalled in RPL option!\n"); |
| /* Packet must be dropped and dio trickle timer reset, see RFC6550 - 11.2.2.2 */ |
| rpl_reset_dio_timer(instance); |
| return 1; |
| } |
| PRINTF("RPL: Single error tolerated\n"); |
| RPL_STAT(rpl_stats.loop_warnings++); |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->flags |= RPL_HDR_OPT_RANK_ERR; |
| return 0; |
| } |
| |
| PRINTF("RPL: Rank OK\n"); |
| |
| return 0; |
| } |
| /*---------------------------------------------------------------------------*/ |
| static void |
| set_rpl_opt(struct net_buf *buf, unsigned uip_ext_opt_offset) |
| { |
| uint8_t temp_len; |
| |
| memmove(UIP_HBHO_NEXT_BUF(buf), UIP_EXT_BUF(buf), uip_len(buf) - UIP_IPH_LEN); |
| memset(UIP_HBHO_BUF(buf), 0, RPL_HOP_BY_HOP_LEN); |
| UIP_HBHO_BUF(buf)->next = UIP_IP_BUF(buf)->proto; |
| UIP_IP_BUF(buf)->proto = UIP_PROTO_HBHO; |
| UIP_HBHO_BUF(buf)->len = RPL_HOP_BY_HOP_LEN - 8; |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->opt_type = UIP_EXT_HDR_OPT_RPL; |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->opt_len = RPL_HDR_OPT_LEN; |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->flags = 0; |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->instance = 0; |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->senderrank = 0; |
| uip_len(buf) += RPL_HOP_BY_HOP_LEN; |
| temp_len = UIP_IP_BUF(buf)->len[1]; |
| UIP_IP_BUF(buf)->len[1] += UIP_HBHO_BUF(buf)->len + 8; |
| if(UIP_IP_BUF(buf)->len[1] < temp_len) { |
| UIP_IP_BUF(buf)->len[0]++; |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |
| int |
| rpl_update_header_empty(struct net_buf *buf) |
| { |
| rpl_instance_t *instance; |
| int uip_ext_opt_offset; |
| int last_uip_ext_len; |
| rpl_parent_t *parent; |
| |
| last_uip_ext_len = uip_ext_len(buf); |
| uip_ext_len(buf) = 0; |
| uip_ext_opt_offset = 2; |
| |
| PRINTF("RPL: Verifying the presence of the RPL header option\n"); |
| |
| switch(UIP_IP_BUF(buf)->proto) { |
| case UIP_PROTO_HBHO: |
| if(UIP_HBHO_BUF(buf)->len != RPL_HOP_BY_HOP_LEN - 8) { |
| PRINTF("RPL: Hop-by-hop extension header has wrong size\n"); |
| uip_ext_len(buf) = last_uip_ext_len; |
| return 0; |
| } |
| if(UIP_EXT_HDR_OPT_RPL_BUF(buf)->opt_type != UIP_EXT_HDR_OPT_RPL) { |
| PRINTF("RPL: Non RPL Hop-by-hop option support not implemented\n"); |
| uip_ext_len(buf) = last_uip_ext_len; |
| return 0; |
| } |
| if(UIP_EXT_HDR_OPT_RPL_BUF(buf)->opt_len != RPL_HDR_OPT_LEN) { |
| PRINTF("RPL: RPL Hop-by-hop option has wrong length\n"); |
| uip_ext_len(buf) = last_uip_ext_len; |
| return 0; |
| } |
| instance = rpl_get_instance(UIP_EXT_HDR_OPT_RPL_BUF(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 0; |
| } |
| break; |
| default: |
| #if RPL_INSERT_HBH_OPTION |
| PRINTF("RPL: No hop-by-hop option found, creating it\n"); |
| if(uip_len(buf) + RPL_HOP_BY_HOP_LEN > UIP_BUFSIZE) { |
| PRINTF("RPL: Packet too long: impossible to add hop-by-hop option\n"); |
| uip_ext_len(buf) = last_uip_ext_len; |
| return 0; |
| } |
| set_rpl_opt(buf, uip_ext_opt_offset); |
| uip_ext_len(buf) = last_uip_ext_len + RPL_HOP_BY_HOP_LEN; |
| #endif |
| return 0; |
| } |
| |
| switch(UIP_EXT_HDR_OPT_BUF(buf)->type) { |
| case UIP_EXT_HDR_OPT_RPL: |
| PRINTF("RPL: Updating RPL option\n"); |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->senderrank = UIP_HTONS(instance->current_dag->rank); |
| |
| /* Check the direction of the down flag, as per Section 11.2.2.3, |
| which states that if a packet is going down it should in |
| general not go back up again. If this happens, a |
| RPL_HDR_OPT_FWD_ERR should be flagged. */ |
| if((UIP_EXT_HDR_OPT_RPL_BUF(buf)->flags & RPL_HDR_OPT_DOWN)) { |
| if(uip_ds6_route_lookup(&UIP_IP_BUF(buf)->destipaddr) == NULL) { |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->flags |= RPL_HDR_OPT_FWD_ERR; |
| PRINTF("RPL forwarding error\n"); |
| /* We should send back the packet to the originating parent, |
| but it is not feasible yet, so we send a No-Path DAO instead */ |
| PRINTF("RPL generate No-Path DAO\n"); |
| parent = rpl_get_parent((uip_lladdr_t *)&ip_buf_ll_src(buf)); |
| if(parent != NULL) { |
| dao_output_target(parent, &UIP_IP_BUF(buf)->destipaddr, RPL_ZERO_LIFETIME); |
| } |
| /* Drop packet */ |
| return 1; |
| } |
| } else { |
| /* 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(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(buf)->flags &= ~RPL_HDR_OPT_DOWN; |
| PRINTF("RPL option going up\n"); |
| } else { |
| /* A DAO route was found so we set the down flag. */ |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->flags |= RPL_HDR_OPT_DOWN; |
| PRINTF("RPL option going down\n"); |
| } |
| } |
| |
| uip_ext_len(buf) = last_uip_ext_len; |
| return 0; |
| default: |
| PRINTF("RPL: Multi Hop-by-hop options not implemented\n"); |
| uip_ext_len(buf) = last_uip_ext_len; |
| return 0; |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |
| int |
| rpl_update_header_final(struct net_buf *buf, 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(buf); |
| uip_ext_len(buf) = 0; |
| uip_ext_opt_offset = 2; |
| |
| if(UIP_IP_BUF(buf)->proto == UIP_PROTO_HBHO) { |
| if(UIP_HBHO_BUF(buf)->len != RPL_HOP_BY_HOP_LEN - 8) { |
| PRINTF("RPL: Non RPL Hop-by-hop options support not implemented\n"); |
| uip_ext_len(buf) = last_uip_ext_len; |
| return 0; |
| } |
| |
| if(UIP_EXT_HDR_OPT_BUF(buf)->type == UIP_EXT_HDR_OPT_RPL) { |
| if(UIP_EXT_HDR_OPT_RPL_BUF(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(buf)->flags = RPL_HDR_OPT_DOWN; |
| } |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->instance = default_instance->instance_id; |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->senderrank = UIP_HTONS(default_instance->current_dag->rank); |
| } |
| } |
| } |
| return 0; |
| } |
| /*---------------------------------------------------------------------------*/ |
| void |
| rpl_remove_header(struct net_buf *buf) |
| { |
| uint8_t temp_len; |
| |
| uip_ext_len(buf) = 0; |
| |
| PRINTF("RPL: Verifying the presence of the RPL header option\n"); |
| switch(UIP_IP_BUF(buf)->proto){ |
| case UIP_PROTO_HBHO: |
| PRINTF("RPL: Removing the RPL header option\n"); |
| UIP_IP_BUF(buf)->proto = UIP_HBHO_BUF(buf)->next; |
| temp_len = UIP_IP_BUF(buf)->len[1]; |
| uip_len(buf) -= UIP_HBHO_BUF(buf)->len + 8; |
| UIP_IP_BUF(buf)->len[1] -= UIP_HBHO_BUF(buf)->len + 8; |
| if(UIP_IP_BUF(buf)->len[1] > temp_len) { |
| UIP_IP_BUF(buf)->len[0]--; |
| } |
| memmove(UIP_EXT_BUF(buf), UIP_HBHO_NEXT_BUF(buf), uip_len(buf) - UIP_IPH_LEN); |
| break; |
| default: |
| PRINTF("RPL: No hop-by-hop Option found\n"); |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |
| uint8_t |
| rpl_invert_header(struct net_buf *buf) |
| { |
| uint8_t uip_ext_opt_offset; |
| uint8_t last_uip_ext_len; |
| |
| last_uip_ext_len = uip_ext_len(buf); |
| uip_ext_len(buf) = 0; |
| uip_ext_opt_offset = 2; |
| |
| PRINTF("RPL: Verifying the presence of the RPL header option\n"); |
| switch(UIP_IP_BUF(buf)->proto) { |
| case UIP_PROTO_HBHO: |
| break; |
| default: |
| PRINTF("RPL: No hop-by-hop Option found\n"); |
| uip_ext_len(buf) = last_uip_ext_len; |
| return 0; |
| } |
| |
| switch (UIP_EXT_HDR_OPT_BUF(buf)->type) { |
| case UIP_EXT_HDR_OPT_RPL: |
| PRINTF("RPL: Updating RPL option (switching direction)\n"); |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->flags &= RPL_HDR_OPT_DOWN; |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->flags ^= RPL_HDR_OPT_DOWN; |
| UIP_EXT_HDR_OPT_RPL_BUF(buf)->senderrank = UIP_HTONS(rpl_get_instance(UIP_EXT_HDR_OPT_RPL_BUF(buf)->instance)->current_dag->rank); |
| uip_ext_len(buf) = last_uip_ext_len; |
| return RPL_HOP_BY_HOP_LEN; |
| default: |
| PRINTF("RPL: Multi Hop-by-hop options not implemented\n"); |
| uip_ext_len(buf) = last_uip_ext_len; |
| return 0; |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |
| void |
| rpl_insert_header(struct net_buf *buf) |
| { |
| #if RPL_INSERT_HBH_OPTION |
| if(default_instance != NULL && !uip_is_addr_mcast(&UIP_IP_BUF(buf)->destipaddr)) { |
| rpl_update_header_empty(buf); |
| } |
| #endif |
| } |
| /*---------------------------------------------------------------------------*/ |
| |
| /** @}*/ |