osd-contiki/core/net/ipv6/uip-nd6.c
2014-04-04 00:09:26 +01:00

1039 lines
35 KiB
C

/**
* \addtogroup uip6
* @{
*/
/**
* \file
* Neighbor discovery (RFC 4861)
* \author Mathilde Durvy <mdurvy@cisco.com>
* \author Julien Abeille <jabeille@cisco.com>
*/
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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 project 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 PROJECT 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 PROJECT 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.
*/
/*
* Copyright (c) 2006, 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.
*
*/
#include <string.h>
#include "net/ipv6/uip-icmp6.h"
#include "net/ipv6/uip-nd6.h"
#include "net/ipv6/uip-ds6.h"
#include "lib/random.h"
#if UIP_CONF_IPV6
/*------------------------------------------------------------------*/
#define DEBUG 0
#include "net/ip/uip-debug.h"
#if UIP_LOGGING
#include <stdio.h>
void uip_log(char *msg);
#define UIP_LOG(m) uip_log(m)
#else
#define UIP_LOG(m)
#endif /* UIP_LOGGING == 1 */
/*------------------------------------------------------------------*/
/** @{ */
/** \name Pointers to the header structures.
* All pointers except UIP_IP_BUF depend on uip_ext_len, which at
* packet reception, is the total length of the extension headers.
*
* The pointer to ND6 options header also depends on nd6_opt_offset,
* which we set in each function.
*
* Care should be taken when manipulating these buffers about the
* value of these length variables
*/
#define UIP_IP_BUF ((struct uip_ip_hdr *)&uip_buf[UIP_LLH_LEN]) /**< Pointer to IP header */
#define UIP_ICMP_BUF ((struct uip_icmp_hdr *)&uip_buf[uip_l2_l3_hdr_len]) /**< Pointer to ICMP header*/
/**@{ Pointers to messages just after icmp header */
#define UIP_ND6_RS_BUF ((uip_nd6_rs *)&uip_buf[uip_l2_l3_icmp_hdr_len])
#define UIP_ND6_RA_BUF ((uip_nd6_ra *)&uip_buf[uip_l2_l3_icmp_hdr_len])
#define UIP_ND6_NS_BUF ((uip_nd6_ns *)&uip_buf[uip_l2_l3_icmp_hdr_len])
#define UIP_ND6_NA_BUF ((uip_nd6_na *)&uip_buf[uip_l2_l3_icmp_hdr_len])
/** @} */
/** Pointer to ND option */
#define UIP_ND6_OPT_HDR_BUF ((uip_nd6_opt_hdr *)&uip_buf[uip_l2_l3_icmp_hdr_len + nd6_opt_offset])
#define UIP_ND6_OPT_PREFIX_BUF ((uip_nd6_opt_prefix_info *)&uip_buf[uip_l2_l3_icmp_hdr_len + nd6_opt_offset])
#define UIP_ND6_OPT_MTU_BUF ((uip_nd6_opt_mtu *)&uip_buf[uip_l2_l3_icmp_hdr_len + nd6_opt_offset])
/** @} */
static uint8_t nd6_opt_offset; /** Offset from the end of the icmpv6 header to the option in uip_buf*/
static uint8_t *nd6_opt_llao; /** Pointer to llao option in uip_buf */
#if !UIP_CONF_ROUTER // TBD see if we move it to ra_input
static uip_nd6_opt_prefix_info *nd6_opt_prefix_info; /** Pointer to prefix information option in uip_buf */
static uip_ipaddr_t ipaddr;
static uip_ds6_prefix_t *prefix; /** Pointer to a prefix list entry */
#endif
static uip_ds6_nbr_t *nbr; /** Pointer to a nbr cache entry*/
static uip_ds6_defrt_t *defrt; /** Pointer to a router list entry */
static uip_ds6_addr_t *addr; /** Pointer to an interface address */
/*------------------------------------------------------------------*/
/* create a llao */
static void
create_llao(uint8_t *llao, uint8_t type) {
llao[UIP_ND6_OPT_TYPE_OFFSET] = type;
llao[UIP_ND6_OPT_LEN_OFFSET] = UIP_ND6_OPT_LLAO_LEN >> 3;
memcpy(&llao[UIP_ND6_OPT_DATA_OFFSET], &uip_lladdr, UIP_LLADDR_LEN);
/* padding on some */
memset(&llao[UIP_ND6_OPT_DATA_OFFSET + UIP_LLADDR_LEN], 0,
UIP_ND6_OPT_LLAO_LEN - 2 - UIP_LLADDR_LEN);
}
/*------------------------------------------------------------------*/
static void
ns_input(void)
{
uint8_t flags;
PRINTF("Received NS from ");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF(" to ");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF(" with target address");
PRINT6ADDR((uip_ipaddr_t *) (&UIP_ND6_NS_BUF->tgtipaddr));
PRINTF("\n");
UIP_STAT(++uip_stat.nd6.recv);
#if UIP_CONF_IPV6_CHECKS
if((UIP_IP_BUF->ttl != UIP_ND6_HOP_LIMIT) ||
(uip_is_addr_mcast(&UIP_ND6_NS_BUF->tgtipaddr)) ||
(UIP_ICMP_BUF->icode != 0)) {
PRINTF("NS received is bad\n");
goto discard;
}
#endif /* UIP_CONF_IPV6_CHECKS */
/* Options processing */
nd6_opt_llao = NULL;
nd6_opt_offset = UIP_ND6_NS_LEN;
while(uip_l3_icmp_hdr_len + nd6_opt_offset < uip_len) {
#if UIP_CONF_IPV6_CHECKS
if(UIP_ND6_OPT_HDR_BUF->len == 0) {
PRINTF("NS received is bad\n");
goto discard;
}
#endif /* UIP_CONF_IPV6_CHECKS */
switch (UIP_ND6_OPT_HDR_BUF->type) {
case UIP_ND6_OPT_SLLAO:
nd6_opt_llao = &uip_buf[uip_l2_l3_icmp_hdr_len + nd6_opt_offset];
#if UIP_CONF_IPV6_CHECKS
/* There must be NO option in a DAD NS */
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
PRINTF("NS received is bad\n");
goto discard;
} else {
#endif /*UIP_CONF_IPV6_CHECKS */
nbr = uip_ds6_nbr_lookup(&UIP_IP_BUF->srcipaddr);
if(nbr == NULL) {
uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr,
(uip_lladdr_t *)&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
0, NBR_STALE);
} else {
uip_lladdr_t *lladdr = (uip_lladdr_t *)uip_ds6_nbr_get_ll(nbr);
if(memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
lladdr, UIP_LLADDR_LEN) != 0) {
memcpy(lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
UIP_LLADDR_LEN);
nbr->state = NBR_STALE;
} else {
if(nbr->state == NBR_INCOMPLETE) {
nbr->state = NBR_STALE;
}
}
}
#if UIP_CONF_IPV6_CHECKS
}
#endif /*UIP_CONF_IPV6_CHECKS */
break;
default:
PRINTF("ND option not supported in NS");
break;
}
nd6_opt_offset += (UIP_ND6_OPT_HDR_BUF->len << 3);
}
addr = uip_ds6_addr_lookup(&UIP_ND6_NS_BUF->tgtipaddr);
if(addr != NULL) {
#if UIP_ND6_DEF_MAXDADNS > 0
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
/* DAD CASE */
#if UIP_CONF_IPV6_CHECKS
if(!uip_is_addr_solicited_node(&UIP_IP_BUF->destipaddr)) {
PRINTF("NS received is bad\n");
goto discard;
}
#endif /* UIP_CONF_IPV6_CHECKS */
if(addr->state != ADDR_TENTATIVE) {
uip_create_linklocal_allnodes_mcast(&UIP_IP_BUF->destipaddr);
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr, &UIP_IP_BUF->destipaddr);
flags = UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
} else {
/** \todo if I sent a NS before him, I win */
uip_ds6_dad_failed(addr);
goto discard;
}
#else /* UIP_ND6_DEF_MAXDADNS > 0 */
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
/* DAD CASE */
goto discard;
#endif /* UIP_ND6_DEF_MAXDADNS > 0 */
}
#if UIP_CONF_IPV6_CHECKS
if(uip_ds6_is_my_addr(&UIP_IP_BUF->srcipaddr)) {
/**
* \NOTE do we do something here? we both are using the same address.
* If we are doing dad, we could cancel it, though we should receive a
* NA in response of DAD NS we sent, hence DAD will fail anyway. If we
* were not doing DAD, it means there is a duplicate in the network!
*/
PRINTF("NS received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
/* Address resolution case */
if(uip_is_addr_solicited_node(&UIP_IP_BUF->destipaddr)) {
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &UIP_IP_BUF->srcipaddr);
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, &UIP_ND6_NS_BUF->tgtipaddr);
flags = UIP_ND6_NA_FLAG_SOLICITED | UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
}
/* NUD CASE */
if(uip_ds6_addr_lookup(&UIP_IP_BUF->destipaddr) == addr) {
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &UIP_IP_BUF->srcipaddr);
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, &UIP_ND6_NS_BUF->tgtipaddr);
flags = UIP_ND6_NA_FLAG_SOLICITED | UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
} else {
#if UIP_CONF_IPV6_CHECKS
PRINTF("NS received is bad\n");
goto discard;
#endif /* UIP_CONF_IPV6_CHECKS */
}
} else {
goto discard;
}
create_na:
/* If the node is a router it should set R flag in NAs */
#if UIP_CONF_ROUTER
flags = flags | UIP_ND6_NA_FLAG_ROUTER;
#endif
uip_ext_len = 0;
UIP_IP_BUF->vtc = 0x60;
UIP_IP_BUF->tcflow = 0;
UIP_IP_BUF->flow = 0;
UIP_IP_BUF->len[0] = 0; /* length will not be more than 255 */
UIP_IP_BUF->len[1] = UIP_ICMPH_LEN + UIP_ND6_NA_LEN + UIP_ND6_OPT_LLAO_LEN;
UIP_IP_BUF->proto = UIP_PROTO_ICMP6;
UIP_IP_BUF->ttl = UIP_ND6_HOP_LIMIT;
UIP_ICMP_BUF->type = ICMP6_NA;
UIP_ICMP_BUF->icode = 0;
UIP_ND6_NA_BUF->flagsreserved = flags;
memcpy(&UIP_ND6_NA_BUF->tgtipaddr, &addr->ipaddr, sizeof(uip_ipaddr_t));
create_llao(&uip_buf[uip_l2_l3_icmp_hdr_len + UIP_ND6_NA_LEN],
UIP_ND6_OPT_TLLAO);
UIP_ICMP_BUF->icmpchksum = 0;
UIP_ICMP_BUF->icmpchksum = ~uip_icmp6chksum();
uip_len =
UIP_IPH_LEN + UIP_ICMPH_LEN + UIP_ND6_NA_LEN + UIP_ND6_OPT_LLAO_LEN;
UIP_STAT(++uip_stat.nd6.sent);
PRINTF("Sending NA to ");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF(" from ");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF(" with target address ");
PRINT6ADDR(&UIP_ND6_NA_BUF->tgtipaddr);
PRINTF("\n");
return;
discard:
uip_len = 0;
return;
}
/*------------------------------------------------------------------*/
void
uip_nd6_ns_output(uip_ipaddr_t * src, uip_ipaddr_t * dest, uip_ipaddr_t * tgt)
{
uip_ext_len = 0;
UIP_IP_BUF->vtc = 0x60;
UIP_IP_BUF->tcflow = 0;
UIP_IP_BUF->flow = 0;
UIP_IP_BUF->proto = UIP_PROTO_ICMP6;
UIP_IP_BUF->ttl = UIP_ND6_HOP_LIMIT;
if(dest == NULL) {
uip_create_solicited_node(tgt, &UIP_IP_BUF->destipaddr);
} else {
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, dest);
}
UIP_ICMP_BUF->type = ICMP6_NS;
UIP_ICMP_BUF->icode = 0;
UIP_ND6_NS_BUF->reserved = 0;
uip_ipaddr_copy((uip_ipaddr_t *) &UIP_ND6_NS_BUF->tgtipaddr, tgt);
UIP_IP_BUF->len[0] = 0; /* length will not be more than 255 */
/*
* check if we add a SLLAO option: for DAD, MUST NOT, for NUD, MAY
* (here yes), for Address resolution , MUST
*/
if(!(uip_ds6_is_my_addr(tgt))) {
if(src != NULL) {
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, src);
} else {
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr, &UIP_IP_BUF->destipaddr);
}
if (uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
PRINTF("Dropping NS due to no suitable source address\n");
uip_len = 0;
return;
}
UIP_IP_BUF->len[1] =
UIP_ICMPH_LEN + UIP_ND6_NS_LEN + UIP_ND6_OPT_LLAO_LEN;
create_llao(&uip_buf[uip_l2_l3_icmp_hdr_len + UIP_ND6_NS_LEN],
UIP_ND6_OPT_SLLAO);
uip_len =
UIP_IPH_LEN + UIP_ICMPH_LEN + UIP_ND6_NS_LEN + UIP_ND6_OPT_LLAO_LEN;
} else {
uip_create_unspecified(&UIP_IP_BUF->srcipaddr);
UIP_IP_BUF->len[1] = UIP_ICMPH_LEN + UIP_ND6_NS_LEN;
uip_len = UIP_IPH_LEN + UIP_ICMPH_LEN + UIP_ND6_NS_LEN;
}
UIP_ICMP_BUF->icmpchksum = 0;
UIP_ICMP_BUF->icmpchksum = ~uip_icmp6chksum();
UIP_STAT(++uip_stat.nd6.sent);
PRINTF("Sending NS to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("with target address");
PRINT6ADDR(tgt);
PRINTF("\n");
return;
}
/*------------------------------------------------------------------*/
/**
* Neighbor Advertisement Processing
*
* we might have to send a pkt that had been buffered while address
* resolution was performed (if we support buffering, see UIP_CONF_QUEUE_PKT)
*
* As per RFC 4861, on link layer that have addresses, TLLAO options MUST be
* included when responding to multicast solicitations, SHOULD be included in
* response to unicast (here we assume it is for now)
*
* NA can be received after sending NS for DAD, Address resolution or NUD. Can
* be unsolicited as well.
* It can trigger update of the state of the neighbor in the neighbor cache,
* router in the router list.
* If the NS was for DAD, it means DAD failed
*
*/
static void
na_input(void)
{
uint8_t is_llchange;
uint8_t is_router;
uint8_t is_solicited;
uint8_t is_override;
PRINTF("Received NA from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("with target address");
PRINT6ADDR((uip_ipaddr_t *) (&UIP_ND6_NA_BUF->tgtipaddr));
PRINTF("\n");
UIP_STAT(++uip_stat.nd6.recv);
/*
* booleans. the three last one are not 0 or 1 but 0 or 0x80, 0x40, 0x20
* but it works. Be careful though, do not use tests such as is_router == 1
*/
is_llchange = 0;
is_router = ((UIP_ND6_NA_BUF->flagsreserved & UIP_ND6_NA_FLAG_ROUTER));
is_solicited =
((UIP_ND6_NA_BUF->flagsreserved & UIP_ND6_NA_FLAG_SOLICITED));
is_override =
((UIP_ND6_NA_BUF->flagsreserved & UIP_ND6_NA_FLAG_OVERRIDE));
#if UIP_CONF_IPV6_CHECKS
if((UIP_IP_BUF->ttl != UIP_ND6_HOP_LIMIT) ||
(UIP_ICMP_BUF->icode != 0) ||
(uip_is_addr_mcast(&UIP_ND6_NA_BUF->tgtipaddr)) ||
(is_solicited && uip_is_addr_mcast(&UIP_IP_BUF->destipaddr))) {
PRINTF("NA received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
/* Options processing: we handle TLLAO, and must ignore others */
nd6_opt_offset = UIP_ND6_NA_LEN;
nd6_opt_llao = NULL;
while(uip_l3_icmp_hdr_len + nd6_opt_offset < uip_len) {
#if UIP_CONF_IPV6_CHECKS
if(UIP_ND6_OPT_HDR_BUF->len == 0) {
PRINTF("NA received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
switch (UIP_ND6_OPT_HDR_BUF->type) {
case UIP_ND6_OPT_TLLAO:
nd6_opt_llao = (uint8_t *)UIP_ND6_OPT_HDR_BUF;
break;
default:
PRINTF("ND option not supported in NA\n");
break;
}
nd6_opt_offset += (UIP_ND6_OPT_HDR_BUF->len << 3);
}
addr = uip_ds6_addr_lookup(&UIP_ND6_NA_BUF->tgtipaddr);
/* Message processing, including TLLAO if any */
if(addr != NULL) {
#if UIP_ND6_DEF_MAXDADNS > 0
if(addr->state == ADDR_TENTATIVE) {
uip_ds6_dad_failed(addr);
}
#endif /*UIP_ND6_DEF_MAXDADNS > 0 */
PRINTF("NA received is bad\n");
goto discard;
} else {
uip_lladdr_t *lladdr;
nbr = uip_ds6_nbr_lookup(&UIP_ND6_NA_BUF->tgtipaddr);
lladdr = (uip_lladdr_t *)uip_ds6_nbr_get_ll(nbr);
if(nbr == NULL) {
goto discard;
}
if(nd6_opt_llao != 0) {
is_llchange =
memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], (void *)lladdr,
UIP_LLADDR_LEN);
}
if(nbr->state == NBR_INCOMPLETE) {
if(nd6_opt_llao == NULL) {
goto discard;
}
memcpy(lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
UIP_LLADDR_LEN);
if(is_solicited) {
nbr->state = NBR_REACHABLE;
nbr->nscount = 0;
/* reachable time is stored in ms */
stimer_set(&(nbr->reachable), uip_ds6_if.reachable_time / 1000);
} else {
nbr->state = NBR_STALE;
}
nbr->isrouter = is_router;
} else {
if(!is_override && is_llchange) {
if(nbr->state == NBR_REACHABLE) {
nbr->state = NBR_STALE;
}
goto discard;
} else {
if(is_override || (!is_override && nd6_opt_llao != 0 && !is_llchange)
|| nd6_opt_llao == 0) {
if(nd6_opt_llao != 0) {
memcpy(lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
UIP_LLADDR_LEN);
}
if(is_solicited) {
nbr->state = NBR_REACHABLE;
/* reachable time is stored in ms */
stimer_set(&(nbr->reachable), uip_ds6_if.reachable_time / 1000);
} else {
if(nd6_opt_llao != 0 && is_llchange) {
nbr->state = NBR_STALE;
}
}
}
}
if(nbr->isrouter && !is_router) {
defrt = uip_ds6_defrt_lookup(&UIP_IP_BUF->srcipaddr);
if(defrt != NULL) {
uip_ds6_defrt_rm(defrt);
}
}
nbr->isrouter = is_router;
}
}
#if UIP_CONF_IPV6_QUEUE_PKT
/* The nbr is now reachable, check if we had buffered a pkt for it */
/*if(nbr->queue_buf_len != 0) {
uip_len = nbr->queue_buf_len;
memcpy(UIP_IP_BUF, nbr->queue_buf, uip_len);
nbr->queue_buf_len = 0;
return;
}*/
if(uip_packetqueue_buflen(&nbr->packethandle) != 0) {
uip_len = uip_packetqueue_buflen(&nbr->packethandle);
memcpy(UIP_IP_BUF, uip_packetqueue_buf(&nbr->packethandle), uip_len);
uip_packetqueue_free(&nbr->packethandle);
return;
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT */
discard:
uip_len = 0;
return;
}
#if UIP_CONF_ROUTER
#if UIP_ND6_SEND_RA
/*---------------------------------------------------------------------------*/
static void
rs_input(void)
{
PRINTF("Received RS from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("\n");
UIP_STAT(++uip_stat.nd6.recv);
#if UIP_CONF_IPV6_CHECKS
/*
* Check hop limit / icmp code
* target address must not be multicast
* if the NA is solicited, dest must not be multicast
*/
if((UIP_IP_BUF->ttl != UIP_ND6_HOP_LIMIT) || (UIP_ICMP_BUF->icode != 0)) {
PRINTF("RS received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
/* Only valid option is Source Link-Layer Address option any thing
else is discarded */
nd6_opt_offset = UIP_ND6_RS_LEN;
nd6_opt_llao = NULL;
while(uip_l3_icmp_hdr_len + nd6_opt_offset < uip_len) {
#if UIP_CONF_IPV6_CHECKS
if(UIP_ND6_OPT_HDR_BUF->len == 0) {
PRINTF("RS received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
switch (UIP_ND6_OPT_HDR_BUF->type) {
case UIP_ND6_OPT_SLLAO:
nd6_opt_llao = (uint8_t *)UIP_ND6_OPT_HDR_BUF;
break;
default:
PRINTF("ND option not supported in RS\n");
break;
}
nd6_opt_offset += (UIP_ND6_OPT_HDR_BUF->len << 3);
}
/* Options processing: only SLLAO */
if(nd6_opt_llao != NULL) {
#if UIP_CONF_IPV6_CHECKS
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
PRINTF("RS received is bad\n");
goto discard;
} else {
#endif /*UIP_CONF_IPV6_CHECKS */
if((nbr = uip_ds6_nbr_lookup(&UIP_IP_BUF->srcipaddr)) == NULL) {
/* we need to add the neighbor */
uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr,
(uip_lladdr_t *)&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], 0, NBR_STALE);
} else {
/* If LL address changed, set neighbor state to stale */
if(memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
uip_ds6_nbr_get_ll(nbr), UIP_LLADDR_LEN) != 0) {
uip_ds6_nbr_t nbr_data = *nbr;
uip_ds6_nbr_rm(nbr);
nbr = uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr,
(uip_lladdr_t *)&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], 0, NBR_STALE);
nbr->reachable = nbr_data.reachable;
nbr->sendns = nbr_data.sendns;
nbr->nscount = nbr_data.nscount;
}
nbr->isrouter = 0;
}
#if UIP_CONF_IPV6_CHECKS
}
#endif /*UIP_CONF_IPV6_CHECKS */
}
/* Schedule a sollicited RA */
uip_ds6_send_ra_sollicited();
discard:
uip_len = 0;
return;
}
/*---------------------------------------------------------------------------*/
void
uip_nd6_ra_output(uip_ipaddr_t * dest)
{
UIP_IP_BUF->vtc = 0x60;
UIP_IP_BUF->tcflow = 0;
UIP_IP_BUF->flow = 0;
UIP_IP_BUF->proto = UIP_PROTO_ICMP6;
UIP_IP_BUF->ttl = UIP_ND6_HOP_LIMIT;
if(dest == NULL) {
uip_create_linklocal_allnodes_mcast(&UIP_IP_BUF->destipaddr);
} else {
/* For sollicited RA */
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, dest);
}
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr, &UIP_IP_BUF->destipaddr);
UIP_ICMP_BUF->type = ICMP6_RA;
UIP_ICMP_BUF->icode = 0;
UIP_ND6_RA_BUF->cur_ttl = uip_ds6_if.cur_hop_limit;
UIP_ND6_RA_BUF->flags_reserved =
(UIP_ND6_M_FLAG << 7) | (UIP_ND6_O_FLAG << 6);
UIP_ND6_RA_BUF->router_lifetime = uip_htons(UIP_ND6_ROUTER_LIFETIME);
//UIP_ND6_RA_BUF->reachable_time = uip_htonl(uip_ds6_if.reachable_time);
//UIP_ND6_RA_BUF->retrans_timer = uip_htonl(uip_ds6_if.retrans_timer);
UIP_ND6_RA_BUF->reachable_time = 0;
UIP_ND6_RA_BUF->retrans_timer = 0;
uip_len = UIP_IPH_LEN + UIP_ICMPH_LEN + UIP_ND6_RA_LEN;
nd6_opt_offset = UIP_ND6_RA_LEN;
#if !UIP_CONF_ROUTER
/* Prefix list */
for(prefix = uip_ds6_prefix_list;
prefix < uip_ds6_prefix_list + UIP_DS6_PREFIX_NB; prefix++) {
if((prefix->isused) && (prefix->advertise)) {
UIP_ND6_OPT_PREFIX_BUF->type = UIP_ND6_OPT_PREFIX_INFO;
UIP_ND6_OPT_PREFIX_BUF->len = UIP_ND6_OPT_PREFIX_INFO_LEN / 8;
UIP_ND6_OPT_PREFIX_BUF->preflen = prefix->length;
UIP_ND6_OPT_PREFIX_BUF->flagsreserved1 = prefix->l_a_reserved;
UIP_ND6_OPT_PREFIX_BUF->validlt = uip_htonl(prefix->vlifetime);
UIP_ND6_OPT_PREFIX_BUF->preferredlt = uip_htonl(prefix->plifetime);
UIP_ND6_OPT_PREFIX_BUF->reserved2 = 0;
uip_ipaddr_copy(&(UIP_ND6_OPT_PREFIX_BUF->prefix), &(prefix->ipaddr));
nd6_opt_offset += UIP_ND6_OPT_PREFIX_INFO_LEN;
uip_len += UIP_ND6_OPT_PREFIX_INFO_LEN;
}
}
#endif /* !UIP_CONF_ROUTER */
/* Source link-layer option */
create_llao((uint8_t *)UIP_ND6_OPT_HDR_BUF, UIP_ND6_OPT_SLLAO);
uip_len += UIP_ND6_OPT_LLAO_LEN;
nd6_opt_offset += UIP_ND6_OPT_LLAO_LEN;
/* MTU */
UIP_ND6_OPT_MTU_BUF->type = UIP_ND6_OPT_MTU;
UIP_ND6_OPT_MTU_BUF->len = UIP_ND6_OPT_MTU_LEN >> 3;
UIP_ND6_OPT_MTU_BUF->reserved = 0;
//UIP_ND6_OPT_MTU_BUF->mtu = uip_htonl(uip_ds6_if.link_mtu);
UIP_ND6_OPT_MTU_BUF->mtu = uip_htonl(1500);
uip_len += UIP_ND6_OPT_MTU_LEN;
nd6_opt_offset += UIP_ND6_OPT_MTU_LEN;
UIP_IP_BUF->len[0] = ((uip_len - UIP_IPH_LEN) >> 8);
UIP_IP_BUF->len[1] = ((uip_len - UIP_IPH_LEN) & 0xff);
/*ICMP checksum */
UIP_ICMP_BUF->icmpchksum = 0;
UIP_ICMP_BUF->icmpchksum = ~uip_icmp6chksum();
UIP_STAT(++uip_stat.nd6.sent);
PRINTF("Sending RA to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("\n");
return;
}
#endif /* UIP_ND6_SEND_RA */
#endif /* UIP_CONF_ROUTER */
#if !UIP_CONF_ROUTER
/*---------------------------------------------------------------------------*/
void
uip_nd6_rs_output(void)
{
UIP_IP_BUF->vtc = 0x60;
UIP_IP_BUF->tcflow = 0;
UIP_IP_BUF->flow = 0;
UIP_IP_BUF->proto = UIP_PROTO_ICMP6;
UIP_IP_BUF->ttl = UIP_ND6_HOP_LIMIT;
uip_create_linklocal_allrouters_mcast(&UIP_IP_BUF->destipaddr);
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr, &UIP_IP_BUF->destipaddr);
UIP_ICMP_BUF->type = ICMP6_RS;
UIP_ICMP_BUF->icode = 0;
UIP_IP_BUF->len[0] = 0; /* length will not be more than 255 */
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
UIP_IP_BUF->len[1] = UIP_ICMPH_LEN + UIP_ND6_RS_LEN;
uip_len = uip_l3_icmp_hdr_len + UIP_ND6_RS_LEN;
} else {
uip_len = uip_l3_icmp_hdr_len + UIP_ND6_RS_LEN + UIP_ND6_OPT_LLAO_LEN;
UIP_IP_BUF->len[1] =
UIP_ICMPH_LEN + UIP_ND6_RS_LEN + UIP_ND6_OPT_LLAO_LEN;
create_llao(&uip_buf[uip_l2_l3_icmp_hdr_len + UIP_ND6_RS_LEN],
UIP_ND6_OPT_SLLAO);
}
UIP_ICMP_BUF->icmpchksum = 0;
UIP_ICMP_BUF->icmpchksum = ~uip_icmp6chksum();
UIP_STAT(++uip_stat.nd6.sent);
PRINTF("Sendin RS to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("\n");
return;
}
/*---------------------------------------------------------------------------*/
/*
* Process a Router Advertisement
*
* - Possible actions when receiving a RA: add router to router list,
* recalculate reachable time, update link hop limit, update retrans timer.
* - If MTU option: update MTU.
* - If SLLAO option: update entry in neighbor cache
* - If prefix option: start autoconf, add prefix to prefix list
*/
void
ra_input(void)
{
PRINTF("Received RA from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("\n");
UIP_STAT(++uip_stat.nd6.recv);
#if UIP_CONF_IPV6_CHECKS
if((UIP_IP_BUF->ttl != UIP_ND6_HOP_LIMIT) ||
(!uip_is_addr_link_local(&UIP_IP_BUF->srcipaddr)) ||
(UIP_ICMP_BUF->icode != 0)) {
PRINTF("RA received is bad");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
if(UIP_ND6_RA_BUF->cur_ttl != 0) {
uip_ds6_if.cur_hop_limit = UIP_ND6_RA_BUF->cur_ttl;
PRINTF("uip_ds6_if.cur_hop_limit %u\n", uip_ds6_if.cur_hop_limit);
}
if(UIP_ND6_RA_BUF->reachable_time != 0) {
if(uip_ds6_if.base_reachable_time !=
uip_ntohl(UIP_ND6_RA_BUF->reachable_time)) {
uip_ds6_if.base_reachable_time = uip_ntohl(UIP_ND6_RA_BUF->reachable_time);
uip_ds6_if.reachable_time = uip_ds6_compute_reachable_time();
}
}
if(UIP_ND6_RA_BUF->retrans_timer != 0) {
uip_ds6_if.retrans_timer = uip_ntohl(UIP_ND6_RA_BUF->retrans_timer);
}
/* Options processing */
nd6_opt_offset = UIP_ND6_RA_LEN;
while(uip_l3_icmp_hdr_len + nd6_opt_offset < uip_len) {
if(UIP_ND6_OPT_HDR_BUF->len == 0) {
PRINTF("RA received is bad");
goto discard;
}
switch (UIP_ND6_OPT_HDR_BUF->type) {
case UIP_ND6_OPT_SLLAO:
PRINTF("Processing SLLAO option in RA\n");
nd6_opt_llao = (uint8_t *) UIP_ND6_OPT_HDR_BUF;
nbr = uip_ds6_nbr_lookup(&UIP_IP_BUF->srcipaddr);
if(nbr == NULL) {
nbr = uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr,
(uip_lladdr_t *)&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
1, NBR_STALE);
} else {
if(nbr->state == NBR_INCOMPLETE) {
nbr->state = NBR_STALE;
}
uip_lladdr_t *lladdr = uip_ds6_nbr_get_ll(nbr);
if(memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
lladdr, UIP_LLADDR_LEN) != 0) {
memcpy(lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
UIP_LLADDR_LEN);
nbr->state = NBR_STALE;
}
nbr->isrouter = 1;
}
break;
case UIP_ND6_OPT_MTU:
PRINTF("Processing MTU option in RA\n");
uip_ds6_if.link_mtu =
uip_ntohl(((uip_nd6_opt_mtu *) UIP_ND6_OPT_HDR_BUF)->mtu);
break;
case UIP_ND6_OPT_PREFIX_INFO:
PRINTF("Processing PREFIX option in RA\n");
nd6_opt_prefix_info = (uip_nd6_opt_prefix_info *) UIP_ND6_OPT_HDR_BUF;
if((uip_ntohl(nd6_opt_prefix_info->validlt) >=
uip_ntohl(nd6_opt_prefix_info->preferredlt))
&& (!uip_is_addr_link_local(&nd6_opt_prefix_info->prefix))) {
/* on-link flag related processing */
if(nd6_opt_prefix_info->flagsreserved1 & UIP_ND6_RA_FLAG_ONLINK) {
prefix =
uip_ds6_prefix_lookup(&nd6_opt_prefix_info->prefix,
nd6_opt_prefix_info->preflen);
if(prefix == NULL) {
if(nd6_opt_prefix_info->validlt != 0) {
if(nd6_opt_prefix_info->validlt != UIP_ND6_INFINITE_LIFETIME) {
prefix = uip_ds6_prefix_add(&nd6_opt_prefix_info->prefix,
nd6_opt_prefix_info->preflen,
uip_ntohl(nd6_opt_prefix_info->
validlt));
} else {
prefix = uip_ds6_prefix_add(&nd6_opt_prefix_info->prefix,
nd6_opt_prefix_info->preflen, 0);
}
}
} else {
switch (nd6_opt_prefix_info->validlt) {
case 0:
uip_ds6_prefix_rm(prefix);
break;
case UIP_ND6_INFINITE_LIFETIME:
prefix->isinfinite = 1;
break;
default:
PRINTF("Updating timer of prefix");
PRINT6ADDR(&prefix->ipaddr);
PRINTF("new value %lu\n", uip_ntohl(nd6_opt_prefix_info->validlt));
stimer_set(&prefix->vlifetime,
uip_ntohl(nd6_opt_prefix_info->validlt));
prefix->isinfinite = 0;
break;
}
}
}
/* End of on-link flag related processing */
/* autonomous flag related processing */
if((nd6_opt_prefix_info->flagsreserved1 & UIP_ND6_RA_FLAG_AUTONOMOUS)
&& (nd6_opt_prefix_info->validlt != 0)
&& (nd6_opt_prefix_info->preflen == UIP_DEFAULT_PREFIX_LEN)) {
uip_ipaddr_copy(&ipaddr, &nd6_opt_prefix_info->prefix);
uip_ds6_set_addr_iid(&ipaddr, &uip_lladdr);
addr = uip_ds6_addr_lookup(&ipaddr);
if((addr != NULL) && (addr->type == ADDR_AUTOCONF)) {
if(nd6_opt_prefix_info->validlt != UIP_ND6_INFINITE_LIFETIME) {
/* The processing below is defined in RFC4862 section 5.5.3 e */
if((uip_ntohl(nd6_opt_prefix_info->validlt) > 2 * 60 * 60) ||
(uip_ntohl(nd6_opt_prefix_info->validlt) >
stimer_remaining(&addr->vlifetime))) {
PRINTF("Updating timer of address");
PRINT6ADDR(&addr->ipaddr);
PRINTF("new value %lu\n",
uip_ntohl(nd6_opt_prefix_info->validlt));
stimer_set(&addr->vlifetime,
uip_ntohl(nd6_opt_prefix_info->validlt));
} else {
stimer_set(&addr->vlifetime, 2 * 60 * 60);
PRINTF("Updating timer of address ");
PRINT6ADDR(&addr->ipaddr);
PRINTF("new value %lu\n", (unsigned long)(2 * 60 * 60));
}
addr->isinfinite = 0;
} else {
addr->isinfinite = 1;
}
} else {
if(uip_ntohl(nd6_opt_prefix_info->validlt) ==
UIP_ND6_INFINITE_LIFETIME) {
uip_ds6_addr_add(&ipaddr, 0, ADDR_AUTOCONF);
} else {
uip_ds6_addr_add(&ipaddr, uip_ntohl(nd6_opt_prefix_info->validlt),
ADDR_AUTOCONF);
}
}
}
/* End of autonomous flag related processing */
}
break;
default:
PRINTF("ND option not supported in RA");
break;
}
nd6_opt_offset += (UIP_ND6_OPT_HDR_BUF->len << 3);
}
defrt = uip_ds6_defrt_lookup(&UIP_IP_BUF->srcipaddr);
if(UIP_ND6_RA_BUF->router_lifetime != 0) {
if(nbr != NULL) {
nbr->isrouter = 1;
}
if(defrt == NULL) {
uip_ds6_defrt_add(&UIP_IP_BUF->srcipaddr,
(unsigned
long)(uip_ntohs(UIP_ND6_RA_BUF->router_lifetime)));
} else {
stimer_set(&(defrt->lifetime),
(unsigned long)(uip_ntohs(UIP_ND6_RA_BUF->router_lifetime)));
}
} else {
if(defrt != NULL) {
uip_ds6_defrt_rm(defrt);
}
}
#if UIP_CONF_IPV6_QUEUE_PKT
/* If the nbr just became reachable (e.g. it was in NBR_INCOMPLETE state
* and we got a SLLAO), check if we had buffered a pkt for it */
/* if((nbr != NULL) && (nbr->queue_buf_len != 0)) {
uip_len = nbr->queue_buf_len;
memcpy(UIP_IP_BUF, nbr->queue_buf, uip_len);
nbr->queue_buf_len = 0;
return;
}*/
if(nbr != NULL && uip_packetqueue_buflen(&nbr->packethandle) != 0) {
uip_len = uip_packetqueue_buflen(&nbr->packethandle);
memcpy(UIP_IP_BUF, uip_packetqueue_buf(&nbr->packethandle), uip_len);
uip_packetqueue_free(&nbr->packethandle);
return;
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT */
discard:
uip_len = 0;
return;
}
#endif /* !UIP_CONF_ROUTER */
/*------------------------------------------------------------------*/
/* ICMPv6 input handlers */
#if UIP_ND6_SEND_NA
UIP_ICMP6_HANDLER(ns_input_handler, ICMP6_NS, UIP_ICMP6_HANDLER_CODE_ANY,
ns_input);
UIP_ICMP6_HANDLER(na_input_handler, ICMP6_NA, UIP_ICMP6_HANDLER_CODE_ANY,
na_input);
#endif
#if UIP_CONF_ROUTER && UIP_ND6_SEND_RA
UIP_ICMP6_HANDLER(rs_input_handler, ICMP6_RS, UIP_ICMP6_HANDLER_CODE_ANY,
rs_input);
#endif
#if !UIP_CONF_ROUTER
UIP_ICMP6_HANDLER(ra_input_handler, ICMP6_RA, UIP_ICMP6_HANDLER_CODE_ANY,
ra_input);
#endif
/*---------------------------------------------------------------------------*/
void
uip_nd6_init()
{
#if UIP_ND6_SEND_NA
/* Only handle NSs if we are prepared to send out NAs */
uip_icmp6_register_input_handler(&ns_input_handler);
/*
* Only handle NAs if we are prepared to send out NAs.
* This is perhaps logically incorrect, but this condition was present in
* uip_process and we keep it until proven wrong
*/
uip_icmp6_register_input_handler(&na_input_handler);
#endif
#if UIP_CONF_ROUTER && UIP_ND6_SEND_RA
/* Only accept RS if we are a router and happy to send out RAs */
uip_icmp6_register_input_handler(&rs_input_handler);
#endif
#if !UIP_CONF_ROUTER
/* Only process RAs if we are not a router */
uip_icmp6_register_input_handler(&ra_input_handler);
#endif
}
/*---------------------------------------------------------------------------*/
/** @} */
#endif /* UIP_CONF_IPV6 */