Sergey Pastor
Webserver+3d print
Diff: cyclone_tcp/ipv6/ndp_router_adv.c
- Revision:
- 0:8918a71cdbe9
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/cyclone_tcp/ipv6/ndp_router_adv.c Sat Feb 04 18:15:49 2017 +0000
@@ -0,0 +1,774 @@
+/**
+ * @file ndp_router_adv.c
+ * @brief Router advertisement service
+ *
+ * @section License
+ *
+ * Copyright (C) 2010-2017 Oryx Embedded SARL. All rights reserved.
+ *
+ * This file is part of CycloneTCP Open.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * @author Oryx Embedded SARL (www.oryx-embedded.com)
+ * @version 1.7.6
+ **/
+
+//Switch to the appropriate trace level
+#define TRACE_LEVEL NDP_TRACE_LEVEL
+
+//Dependencies
+#include "core/net.h"
+#include "core/ip.h"
+#include "ipv6/ipv6.h"
+#include "ipv6/ipv6_misc.h"
+#include "ipv6/icmpv6.h"
+#include "ipv6/ndp.h"
+#include "ipv6/ndp_cache.h"
+#include "ipv6/ndp_misc.h"
+#include "ipv6/ndp_router_adv.h"
+#include "debug.h"
+
+//Check TCP/IP stack configuration
+#if (IPV6_SUPPORT == ENABLED && NDP_ROUTER_ADV_SUPPORT == ENABLED)
+
+//Tick counter to handle periodic operations
+systime_t ndpRouterAdvTickCounter;
+
+
+/**
+ * @brief Initialize settings with default values
+ * @param[out] settings Structure that contains the RA service configuration variables
+ **/
+
+void ndpRouterAdvGetDefaultSettings(NdpRouterAdvSettings *settings)
+{
+ //Underlying network interface
+ settings->interface = netGetDefaultInterface();
+
+ //The maximum time allowed between sending unsolicited multicast
+ //Router Advertisements from the interface
+ settings->maxRtrAdvInterval = NDP_MAX_RTR_ADVERT_INTERVAL;
+
+ //The minimum time allowed between sending unsolicited multicast
+ //Router Advertisements from the interface
+ settings->minRtrAdvInterval = NDP_MAX_RTR_ADVERT_INTERVAL / 3;
+
+ //The default value to be placed in the Cur Hop Limit field in the
+ //Router Advertisement messages sent by the router
+ settings->curHopLimit = 0;
+
+ //The value to be placed in the Managed Address Configuration
+ //flag in the Router Advertisement
+ settings->managedFlag = FALSE;
+
+ //The value to be placed in the Other Configuration flag
+ //in the Router Advertisement
+ settings->otherConfigFlag = FALSE;
+
+ //The value to be placed in the Mobile IPv6 Home Agent
+ //flag in the Router Advertisement
+ settings->homeAgentFlag = FALSE;
+
+ //The value to be placed in the Router Selection Preferences
+ //field in the Router Advertisement
+ settings->preference = NDP_ROUTER_SEL_PREFERENCE_MEDIUM;
+
+ //The value to be placed in the Neighbor Discovery Proxy
+ //flag in the Router Advertisement
+ settings->proxyFlag = FALSE;
+
+ //The value to be placed in the Router Lifetime field of
+ //Router Advertisements sent from the interface
+ settings->defaultLifetime = 3 * (NDP_MAX_RTR_ADVERT_INTERVAL / 1000);
+
+ //The value to be placed in the Reachable Time field in the
+ //Router Advertisement messages sent by the router
+ settings->reachableTime = 0;
+
+ //The value to be placed in the Retrans Timer field in the
+ //Router Advertisement messages sent by the router
+ settings->retransTimer = 0;
+
+ //The value to be placed in the MTU option sent by the router
+ settings->linkMtu = 0;
+
+ //A list of prefixes to be placed in Prefix Information options (PIO)
+ //in Router Advertisement messages sent from the interface
+ settings->prefixList = NULL;
+ settings->prefixListLength = 0;
+
+ //A list of routes to be placed in Route Information options (RIO)
+ //in Router Advertisement messages sent from the interface
+ settings->routeList = NULL;
+ settings->routeListLength = 0;
+
+ //A list of header compression contexts to be placed in the 6LoWPAN Context
+ //options (6CO) in Router Advertisement messages sent from the interface
+ settings->contextList = NULL;
+ settings->contextListLength = 0;
+}
+
+
+/**
+ * @brief RA service initialization
+ * @param[in] context Pointer to the RA service context
+ * @param[in] settings RA service configuration variables
+ * @return Error code
+ **/
+
+error_t ndpRouterAdvInit(NdpRouterAdvContext *context, const NdpRouterAdvSettings *settings)
+{
+ NetInterface *interface;
+
+ //Debug message
+ TRACE_INFO("Initializing Router Advertisement service...\r\n");
+
+ //Ensure the parameters are valid
+ if(!context || !settings)
+ return ERROR_INVALID_PARAMETER;
+
+ //Valid network interface?
+ if(!settings->interface)
+ return ERROR_INVALID_PARAMETER;
+
+ //Get exclusive access
+ osAcquireMutex(&netMutex);
+
+ //Point to the underlying network interface
+ interface = settings->interface;
+
+ //Clear the RA service context
+ memset(context, 0, sizeof(NdpRouterAdvContext));
+ //Save user settings
+ context->settings = *settings;
+
+ //The RA service is currently disabled on the interface
+ context->running = FALSE;
+ //Attach the RA service context to the network interface
+ interface->ndpRouterAdvContext = context;
+
+ //Release exclusive access
+ osReleaseMutex(&netMutex);
+
+ //Successful initialization
+ return NO_ERROR;
+}
+
+
+/**
+ * @brief Start RA service
+ * @param[in] context Pointer to the RA service context
+ * @return Error code
+ **/
+
+error_t ndpRouterAdvStart(NdpRouterAdvContext *context)
+{
+ error_t error;
+ NetInterface *interface;
+
+ //Check parameter
+ if(context == NULL)
+ return ERROR_INVALID_PARAMETER;
+
+ //Debug message
+ TRACE_INFO("Starting Router Advertisement service...\r\n");
+
+ //Get exclusive access
+ osAcquireMutex(&netMutex);
+
+ //Check whether the service is running
+ if(!context->running)
+ {
+ //Point to the underlying network interface
+ interface = context->settings.interface;
+
+ //Join the All-Routers multicast address
+ error = ipv6JoinMulticastGroup(interface, &IPV6_LINK_LOCAL_ALL_ROUTERS_ADDR);
+
+ //Successful membership registration?
+ if(!error)
+ {
+ //Reset variables
+ context->timestamp = osGetSystemTime();
+ context->timeout = 0;
+ context->routerAdvCount = 0;
+
+ //Enable the router to forward packets to or from the interface
+ interface->ipv6Context.isRouter = TRUE;
+
+ //Default Hop Limit value
+ if(context->settings.curHopLimit != 0)
+ interface->ipv6Context.curHopLimit = context->settings.curHopLimit;
+
+ //The time a node assumes a neighbor is reachable
+ if(context->settings.reachableTime != 0)
+ interface->ndpContext.reachableTime = context->settings.reachableTime;
+
+ //The time between retransmissions of NS messages
+ if(context->settings.retransTimer != 0)
+ interface->ndpContext.retransTimer = context->settings.retransTimer;
+
+ //Start transmitting Router Advertisements
+ context->running = TRUE;
+ }
+ }
+ else
+ {
+ //The service is already running...
+ error = NO_ERROR;
+ }
+
+ //Release exclusive access
+ osReleaseMutex(&netMutex);
+
+ //Return status code
+ return error;
+}
+
+
+/**
+ * @brief Stop RA service
+ * @param[in] context Pointer to the RA service context
+ * @return Error code
+ **/
+
+error_t ndpRouterAdvStop(NdpRouterAdvContext *context)
+{
+ error_t error;
+ NetInterface *interface;
+
+ //Check parameter
+ if(context == NULL)
+ return ERROR_INVALID_PARAMETER;
+
+ //Debug message
+ TRACE_INFO("Stopping Router Advertisement service...\r\n");
+
+ //Get exclusive access
+ osAcquireMutex(&netMutex);
+
+ //Check whether the service is running
+ if(context->running)
+ {
+ //Point to the underlying network interface
+ interface = context->settings.interface;
+
+ //The router should transmit one or more final multicast Router
+ //Advertisements with a Router Lifetime field of zero
+ ndpSendRouterAdv(context, 0);
+
+ //Leave the All-Routers multicast address
+ error = ipv6LeaveMulticastGroup(interface, &IPV6_LINK_LOCAL_ALL_ROUTERS_ADDR);
+
+ //Restore default parameters
+ interface->ipv6Context.curHopLimit = IPV6_DEFAULT_HOP_LIMIT;
+ interface->ndpContext.reachableTime = NDP_REACHABLE_TIME;
+ interface->ndpContext.retransTimer = NDP_RETRANS_TIMER;
+
+ //Stop transmitting Router Advertisements
+ context->running = FALSE;
+ }
+ else
+ {
+ //The service is not running...
+ error = NO_ERROR;
+ }
+
+ //Release exclusive access
+ osReleaseMutex(&netMutex);
+
+ //Return status code
+ return error;
+}
+
+
+/**
+ * @brief RA service timer handler
+ * @param[in] context Pointer to the RA service context
+ **/
+
+void ndpRouterAdvTick(NdpRouterAdvContext *context)
+{
+ systime_t time;
+ NetInterface *interface;
+ NdpRouterAdvSettings *settings;
+
+ //Make sure the RA service has been properly instantiated
+ if(context == NULL)
+ return;
+
+ //Point to the underlying network interface
+ interface = context->settings.interface;
+ //Point to the router configuration variables
+ settings = &context->settings;
+
+ //Get current time
+ time = osGetSystemTime();
+
+ //Make sure that the link is up and the service is running
+ if(interface->linkState && context->running)
+ {
+ //Make sure that a valid link-local address has been assigned to the interface
+ if(ipv6GetLinkLocalAddrState(interface) == IPV6_ADDR_STATE_PREFERRED)
+ {
+ //Check current time
+ if(timeCompare(time, context->timestamp + context->timeout) >= 0)
+ {
+ //Send an unsolicited Router Advertisement
+ ndpSendRouterAdv(context, context->settings.defaultLifetime);
+
+ //Save the time at which the message was sent
+ context->timestamp = time;
+
+ //Whenever a multicast advertisement is sent from an interface, the
+ //timer is reset to a uniformly distributed random value between
+ //MinRtrAdvInterval and MaxRtrAdvInterval
+ context->timeout = netGetRandRange(settings->minRtrAdvInterval,
+ settings->maxRtrAdvInterval);
+
+ //First Router Advertisements to be sent from this interface?
+ if(context->routerAdvCount < NDP_MAX_INITIAL_RTR_ADVERTISEMENTS)
+ {
+ //For the first few advertisements sent from an interface when it
+ //becomes an advertising interface, the randomly chosen interval
+ //should not be greater than MAX_INITIAL_RTR_ADVERT_INTERVAL
+ context->timeout = MIN(context->timeout, NDP_MAX_INITIAL_RTR_ADVERT_INTERVAL);
+ }
+
+ //Increment counter
+ context->routerAdvCount++;
+ }
+ }
+ }
+}
+
+
+/**
+ * @brief Callback function for link change event
+ * @param[in] context Pointer to the RA service context
+ **/
+
+void ndpRouterAdvLinkChangeEvent(NdpRouterAdvContext *context)
+{
+ NetInterface *interface;
+
+ //Make sure the RA service has been properly instantiated
+ if(context == NULL)
+ return;
+
+ //Point to the underlying network interface
+ interface = context->settings.interface;
+
+ //Reset variables
+ context->timestamp = osGetSystemTime();
+ context->timeout = 0;
+ context->routerAdvCount = 0;
+
+ //Default Hop Limit value
+ if(context->settings.curHopLimit != 0)
+ interface->ipv6Context.curHopLimit = context->settings.curHopLimit;
+
+ //The time a node assumes a neighbor is reachable
+ if(context->settings.reachableTime != 0)
+ interface->ndpContext.reachableTime = context->settings.reachableTime;
+
+ //The time between retransmissions of NS messages
+ if(context->settings.retransTimer != 0)
+ interface->ndpContext.retransTimer = context->settings.retransTimer;
+}
+
+
+/**
+ * @brief Router Solicitation message processing
+ * @param[in] interface Underlying network interface
+ * @param[in] pseudoHeader IPv6 pseudo header
+ * @param[in] buffer Multi-part buffer containing the Router Advertisement message
+ * @param[in] offset Offset to the first byte of the message
+ * @param[in] hopLimit Hop Limit field from IPv6 header
+ **/
+
+void ndpProcessRouterSol(NetInterface *interface, Ipv6PseudoHeader *pseudoHeader,
+ const NetBuffer *buffer, size_t offset, uint8_t hopLimit)
+{
+ error_t error;
+ uint_t n;
+ size_t length;
+ systime_t time;
+ systime_t delay;
+ NdpRouterAdvContext *context;
+ NdpRouterSolMessage *message;
+ NdpLinkLayerAddrOption *option;
+ NdpNeighborCacheEntry *entry;
+
+ //Point to the RA service context
+ context = interface->ndpRouterAdvContext;
+
+ //A host must silently discard any received Router Solicitation
+ if(context == NULL)
+ return;
+
+ //Get current time
+ time = osGetSystemTime();
+
+ //Retrieve the length of the message
+ length = netBufferGetLength(buffer) - offset;
+
+ //Check the length of the Router Solicitation message
+ if(length < sizeof(NdpRouterSolMessage))
+ return;
+
+ //Point to the beginning of the message
+ message = netBufferAt(buffer, offset);
+ //Sanity check
+ if(message == NULL)
+ return;
+
+ //Debug message
+ TRACE_INFO("Router Solicitation message received (%" PRIuSIZE " bytes)...\r\n", length);
+ //Dump message contents for debugging purpose
+ ndpDumpRouterSolMessage(message);
+
+ //The IPv6 Hop Limit field must have a value of 255 to ensure
+ //that the packet has not been forwarded by a router
+ if(hopLimit != NDP_HOP_LIMIT)
+ return;
+
+ //ICMPv6 Code must be 0
+ if(message->code)
+ return;
+
+ //Calculate the length of the Options field
+ length -= sizeof(NdpRouterSolMessage);
+
+ //Parse Options field
+ error = ndpCheckOptions(message->options, length);
+ //All included options must have a length that is greater than zero
+ if(error)
+ return;
+
+ //Search for the Source Link-Layer Address option
+ option = ndpGetOption(message->options,
+ length, NDP_OPT_SOURCE_LINK_LAYER_ADDR);
+
+ //Source Link-Layer Address option found?
+ if(option != NULL && option->length == 1)
+ {
+ //Debug message
+ TRACE_DEBUG(" Source Link-Layer Address = %s\r\n",
+ macAddrToString(&option->linkLayerAddr, NULL));
+
+ //The Source Link-Layer Address option must not be included when the
+ //source IP address is the unspecified address
+ if(ipv6CompAddr(&pseudoHeader->srcAddr, &IPV6_UNSPECIFIED_ADDR))
+ return;
+
+ //Search the Neighbor Cache for the source address of the solicitation
+ entry = ndpFindNeighborCacheEntry(interface, &pseudoHeader->srcAddr);
+
+ //No matching entry has been found?
+ if(!entry)
+ {
+ //Create an entry
+ entry = ndpCreateNeighborCacheEntry(interface);
+
+ //Neighbor Cache entry successfully created?
+ if(entry)
+ {
+ //Record the IPv6 and the corresponding MAC address
+ entry->ipAddr = pseudoHeader->srcAddr;
+ entry->macAddr = option->linkLayerAddr;
+ //The IsRouter flag must be set to FALSE
+ entry->isRouter = FALSE;
+ //Save current time
+ entry->timestamp = time;
+ //Enter the STALE state
+ entry->state = NDP_STATE_STALE;
+ }
+ }
+ else
+ {
+ //If a Neighbor Cache entry for the solicitation's sender exists
+ //the entry's IsRouter flag must be set to FALSE
+ entry->isRouter = FALSE;
+
+ //INCOMPLETE state?
+ if(entry->state == NDP_STATE_INCOMPLETE)
+ {
+ //Record link-layer address
+ entry->macAddr = option->linkLayerAddr;
+ //Send all the packets that are pending for transmission
+ n = ndpSendQueuedPackets(interface, entry);
+ //Save current time
+ entry->timestamp = time;
+
+ //Check whether any packets have been sent
+ if(n > 0)
+ {
+ //Start delay timer
+ entry->timeout = NDP_DELAY_FIRST_PROBE_TIME;
+ //Switch to the DELAY state
+ entry->state = NDP_STATE_DELAY;
+ }
+ else
+ {
+ //Enter the STALE state
+ entry->state = NDP_STATE_STALE;
+ }
+ }
+ //REACHABLE, STALE, DELAY or PROBE state?
+ else
+ {
+ //Different link-layer address than cached?
+ if(!macCompAddr(&entry->macAddr, &option->linkLayerAddr))
+ {
+ //Update link-layer address
+ entry->macAddr = option->linkLayerAddr;
+ //Save current time
+ entry->timestamp = time;
+ //Enter the STALE state
+ entry->state = NDP_STATE_STALE;
+ }
+ }
+ }
+ }
+
+ //Upon receipt of a Router Solicitation, compute a random delay within the
+ //range 0 through MAX_RA_DELAY_TIME
+ delay = netGetRandRange(0, NDP_MAX_RA_DELAY_TIME);
+
+ //If the computed value corresponds to a time later than the time the next
+ //multicast Router Advertisement is scheduled to be sent, ignore the random
+ //delay and send the advertisement at the already-scheduled time
+ if(timeCompare(time + delay, context->timestamp + context->timeout) > 0)
+ return;
+
+ //Check whether the router sent a multicast Router Advertisement (solicited
+ //or unsolicited) within the last MIN_DELAY_BETWEEN_RAS seconds
+ if(timeCompare(time, context->timestamp + NDP_MIN_DELAY_BETWEEN_RAS) < 0)
+ {
+ //Schedule the advertisement to be sent at a time corresponding to
+ //MIN_DELAY_BETWEEN_RAS plus the random value after the previous
+ //advertisement was sent. This ensures that the multicast Router
+ //Advertisements are rate limited
+ context->timeout = NDP_MIN_DELAY_BETWEEN_RAS + delay;
+ }
+ else
+ {
+ //Schedule the sending of a Router Advertisement at the time given
+ //by the random value
+ context->timeout = time + delay - context->timestamp;
+ }
+}
+
+
+/**
+ * @brief Send a Router Advertisement message
+ * @param[in] context Pointer to the RA service context
+ * @param[in] routerLifetime Router Lifetime field
+ * @return Error code
+ **/
+
+error_t ndpSendRouterAdv(NdpRouterAdvContext *context, uint16_t routerLifetime)
+{
+ error_t error;
+ uint_t i;
+ uint32_t n;
+ size_t offset;
+ size_t length;
+ NetBuffer *buffer;
+ NetInterface *interface;
+ NdpRouterAdvMessage *message;
+ NdpRouterAdvSettings *settings;
+ Ipv6PseudoHeader pseudoHeader;
+
+ //Point to the underlying network interface
+ interface = context->settings.interface;
+ //Point to the router configuration variables
+ settings = &context->settings;
+
+ //The destination address is typically the all-nodes multicast address
+ pseudoHeader.destAddr = IPV6_LINK_LOCAL_ALL_NODES_ADDR;
+
+ //Routers must use their link-local address as the source for Router
+ //Advertisement messages so that hosts can uniquely identify routers
+ error = ipv6SelectSourceAddr(&interface,
+ &pseudoHeader.destAddr, &pseudoHeader.srcAddr);
+
+ //No link-local address assigned to the interface?
+ if(error)
+ return error;
+
+ //Compute the maximum size of the Router Advertisement message
+ length = sizeof(NdpRouterAdvMessage) +
+ sizeof(NdpLinkLayerAddrOption) + sizeof(NdpMtuOption) +
+ settings->prefixListLength * sizeof(NdpPrefixInfoOption) +
+ settings->routeListLength * sizeof(NdpRouteInfoOption) +
+ settings->contextListLength * sizeof(NdpContextOption);
+
+ //Sanity check
+ if((length + sizeof(Ipv6Header)) > IPV6_DEFAULT_MTU)
+ return ERROR_FAILURE;
+
+ //Allocate a memory buffer to hold the Router Advertisement message
+ buffer = ipAllocBuffer(length, &offset);
+ //Failed to allocate memory?
+ if(buffer == NULL)
+ return ERROR_OUT_OF_MEMORY;
+
+ //Point to the beginning of the message
+ message = netBufferAt(buffer, offset);
+
+ //Format Router Advertisement message
+ message->type = ICMPV6_TYPE_ROUTER_ADV;
+ message->code = 0;
+ message->checksum = 0;
+ message->curHopLimit = settings->curHopLimit;
+ message->m = settings->managedFlag;
+ message->o = settings->otherConfigFlag;
+ message->h = settings->homeAgentFlag;
+ message->prf = settings->preference;
+ message->p = settings->proxyFlag;
+ message->reserved = 0;
+ message->routerLifetime = htons(routerLifetime);
+ message->reachableTime = htonl(settings->reachableTime);
+ message->retransTimer = htonl(settings->retransTimer);
+
+ //If the Router Lifetime is zero, the preference value must be
+ //set to zero by the sender
+ if(routerLifetime == 0)
+ message->prf = NDP_ROUTER_SEL_PREFERENCE_MEDIUM;
+
+ //Length of the message, excluding any option
+ length = sizeof(NdpRouterAdvMessage);
+
+#if (ETH_SUPPORT == ENABLED)
+ //Check whether a MAC address has been assigned to the interface
+ if(!macCompAddr(&interface->macAddr, &MAC_UNSPECIFIED_ADDR))
+ {
+ //Add Source Link-Layer Address option
+ ndpAddOption(message, &length, NDP_OPT_SOURCE_LINK_LAYER_ADDR,
+ &interface->macAddr, sizeof(MacAddr));
+ }
+#endif
+
+ //A value of zero indicates that no MTU option is sent
+ if(settings->linkMtu > 0)
+ {
+ NdpMtuOption mtuOption;
+
+ //The MTU option specifies the recommended MTU for the link
+ mtuOption.reserved = 0;
+ mtuOption.mtu = htonl(settings->linkMtu);
+
+ //Add MTU option
+ ndpAddOption(message, &length, NDP_OPT_MTU,
+ (uint8_t *) &mtuOption + sizeof(NdpOption),
+ sizeof(NdpMtuOption) - sizeof(NdpOption));
+ }
+
+ //Loop through the list of IPv6 prefixes
+ for(i = 0; i < settings->prefixListLength; i++)
+ {
+ NdpPrefixInfoOption prefixInfoOption;
+
+ //The Prefix Information option provide hosts with on-link
+ //prefixes and prefixes for Address Autoconfiguration
+ prefixInfoOption.prefixLength = settings->prefixList[i].length;
+ prefixInfoOption.l = settings->prefixList[i].onLinkFlag;
+ prefixInfoOption.a = settings->prefixList[i].autonomousFlag;
+ prefixInfoOption.reserved1 = 0;
+ prefixInfoOption.validLifetime = htonl(settings->prefixList[i].validLifetime);
+ prefixInfoOption.preferredLifetime = htonl(settings->prefixList[i].preferredLifetime);
+ prefixInfoOption.reserved2 = 0;
+ prefixInfoOption.prefix = settings->prefixList[i].prefix;
+
+ //Add Prefix Information option (PIO)
+ ndpAddOption(message, &length, NDP_OPT_PREFIX_INFORMATION,
+ (uint8_t *) &prefixInfoOption + sizeof(NdpOption),
+ sizeof(NdpPrefixInfoOption) - sizeof(NdpOption));
+ }
+
+ //Loop through the list of routes
+ for(i = 0; i < settings->routeListLength; i++)
+ {
+ NdpRouteInfoOption routeInfoOption;
+
+ //The Route Information option specifies prefixes that are
+ //reachable via the router
+ routeInfoOption.prefixLength = settings->routeList[i].length;
+ routeInfoOption.reserved1 = 0;
+ routeInfoOption.prf = settings->routeList[i].preference;
+ routeInfoOption.reserved2 = 0;
+ routeInfoOption.routeLifetime = htonl(settings->routeList[i].routeLifetime);
+ routeInfoOption.prefix = settings->routeList[i].prefix;
+
+ //Add Route Information option (RIO)
+ ndpAddOption(message, &length, NDP_OPT_ROUTE_INFORMATION,
+ (uint8_t *) &routeInfoOption + sizeof(NdpOption),
+ sizeof(NdpRouteInfoOption) - sizeof(NdpOption));
+ }
+
+ //Loop through the list of 6LoWPAN compression contexts
+ for(i = 0; i < settings->contextListLength; i++)
+ {
+ NdpContextOption contextOption;
+
+ //The 6LoWPAN Context option (6CO) carries prefix information for
+ //LoWPAN header compression
+ contextOption.contextLength = settings->contextList[i].length;
+ contextOption.reserved1 = 0;
+ contextOption.c = settings->contextList[i].compression;
+ contextOption.cid = settings->contextList[i].cid;
+ contextOption.reserved2 = 0;
+ contextOption.validLifetime = htons(settings->contextList[i].validLifetime);
+ contextOption.contextPrefix = settings->contextList[i].prefix;
+
+ //Calculate the length of the option in bytes
+ n = sizeof(NdpContextOption) - sizeof(Ipv6Addr) + (contextOption.contextLength / 8);
+
+ //Add 6LoWPAN Context option (6CO)
+ ndpAddOption(message, &length, NDP_OPT_6LOWPAN_CONTEXT,
+ (uint8_t *) &contextOption + sizeof(NdpOption), n - sizeof(NdpOption));
+ }
+
+ //Adjust the length of the multi-part buffer
+ netBufferSetLength(buffer, offset + length);
+
+ //Format IPv6 pseudo header
+ pseudoHeader.length = htonl(length);
+ pseudoHeader.reserved = 0;
+ pseudoHeader.nextHeader = IPV6_ICMPV6_HEADER;
+
+ //Calculate ICMPv6 header checksum
+ message->checksum = ipCalcUpperLayerChecksumEx(&pseudoHeader,
+ sizeof(Ipv6PseudoHeader), buffer, offset, length);
+
+ //Debug message
+ TRACE_INFO("Sending Router Advertisement message (%" PRIuSIZE " bytes)...\r\n", length);
+ //Dump message contents for debugging purpose
+ ndpDumpRouterAdvMessage(message);
+
+ //Send Router Advertisement message
+ error = ipv6SendDatagram(interface, &pseudoHeader, buffer, offset, NDP_HOP_LIMIT);
+
+ //Free previously allocated memory
+ netBufferFree(buffer);
+ //Return status code
+ return error;
+}
+
+#endif
+