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thread_nd.c

00001 /*
00002  * Copyright (c) 2014-2017, Arm Limited and affiliates.
00003  * SPDX-License-Identifier: BSD-3-Clause
00004  *
00005  * Redistribution and use in source and binary forms, with or without
00006  * modification, are permitted provided that the following conditions are met:
00007  *
00008  * 1. Redistributions of source code must retain the above copyright
00009  *    notice, this list of conditions and the following disclaimer.
00010  * 2. Redistributions in binary form must reproduce the above copyright
00011  *    notice, this list of conditions and the following disclaimer in the
00012  *    documentation and/or other materials provided with the distribution.
00013  * 3. Neither the name of the copyright holder nor the
00014  *    names of its contributors may be used to endorse or promote products
00015  *    derived from this software without specific prior written permission.
00016  *
00017  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
00018  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
00019  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
00020  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
00021  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
00022  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
00023  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00024  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00025  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
00026  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
00027  * POSSIBILITY OF SUCH DAMAGE.
00028  */
00029 
00030 /*
00031  * \file thread_nd.c
00032  * \brief Add short description about this file!!!
00033  *
00034  */
00035 
00036 #include "nsconfig.h"
00037 #ifdef HAVE_THREAD
00038 #ifdef HAVE_THREAD_NEIGHBOR_DISCOVERY
00039 #include <string.h>
00040 #include <ns_types.h>
00041 #include <nsdynmemLIB.h>
00042 #include "eventOS_event.h"
00043 #include "common_functions.h"
00044 #include "socket_api.h"
00045 #include "Core/include/socket.h"
00046 #include "NWK_INTERFACE/Include/protocol.h"
00047 #include "Common_Protocols/ipv6.h"
00048 #include "6LoWPAN/Bootstraps/protocol_6lowpan.h"
00049 #include "net_thread_test.h"
00050 #include "ns_trace.h"
00051 #include "6LoWPAN/Thread/thread_common.h"
00052 #include "6LoWPAN/Thread/thread_routing.h"
00053 #include "6LoWPAN/Thread/thread_nd.h"
00054 #include "6LoWPAN/Thread/thread_joiner_application.h"
00055 #include "6LoWPAN/Thread/thread_extension.h"
00056 #include "6LoWPAN/Thread/thread_resolution_client.h"
00057 #include "6LoWPAN/Thread/thread_resolution_server.h"
00058 #include "6LoWPAN/Thread/thread_bbr_api_internal.h"
00059 #include "6LoWPAN/Thread/thread_extension_bbr.h"
00060 #include "6LoWPAN/MAC/mac_helper.h"
00061 #include "Common_Protocols/icmpv6.h"
00062 #include "MLE/mle.h"
00063 #include "dhcp_service_api.h"
00064 #include "Service_Libs/nd_proxy/nd_proxy.h"
00065 
00066 #define TRACE_GROUP "thdn"
00067 
00068 static thread_resolution_server_addr_query_cb  thread_nd_address_query_lookup;
00069 static thread_resolution_client_error_cb thread_nd_address_error;
00070 static thread_resolution_client_notification_cb thread_nd_coap_notification_callback;
00071 
00072 void thread_nd_service_delete(int8_t interfaceId)
00073 {
00074     (void)interfaceId;
00075 }
00076 
00077 int thread_nd_client_service_activate(int8_t interfaceId)
00078 {
00079     thread_resolution_client_init(interfaceId);
00080     thread_resolution_client_set_error_cb(interfaceId, thread_nd_address_error);
00081     return 0;
00082 }
00083 
00084 int thread_nd_service_activate(int8_t interfaceId)
00085 {
00086     /* We assume this is set before we activate, and doesn't change */
00087     thread_resolution_server_init(interfaceId, thread_nd_address_query_lookup);
00088     thread_resolution_client_init(interfaceId);
00089     thread_resolution_client_set_error_cb(interfaceId, thread_nd_address_error);
00090     thread_resolution_client_set_notification_cb(interfaceId, thread_nd_coap_notification_callback);
00091     return 0;
00092 }
00093 
00094 int thread_nd_service_disable(int8_t interfaceId)
00095 {
00096     /* Doesn't hurt if we call thread_resolution_xxx_delete unconditionally */
00097     thread_resolution_server_delete(interfaceId);
00098     thread_resolution_client_delete(interfaceId);
00099     return 0;
00100 }
00101 
00102 static bool thread_nd_probe_transmit(protocol_interface_info_entry_t *cur, ipv6_neighbour_t *entry)
00103 {
00104     //Generate Ping
00105     tr_debug("Sending Ping Echo (NUD): %s", trace_ipv6(entry->ip_address));
00106 
00107     //ADD NeighCache
00108     icmpv6_build_echo_req(cur, entry->ip_address);
00109 
00110     return true;
00111 }
00112 
00113 static void thread_nd_coap_response_callback(int8_t interface_id, int8_t status, const uint8_t ip_addr[16], uint16_t loc_addr, uint32_t last_transaction_time, uint8_t *mleid)
00114 {
00115     protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
00116     if (!cur) {
00117         return;
00118     }
00119     (void) last_transaction_time;
00120     (void) mleid;
00121 
00122     ipv6_neighbour_t *neighbour_entry = ipv6_neighbour_lookup(&cur->ipv6_neighbour_cache, ip_addr);
00123     if (neighbour_entry) {
00124         if (status == 0) {
00125             uint8_t ll_addr[4];
00126             common_write_16_bit(cur->mac_parameters->pan_id, ll_addr + 0);
00127             common_write_16_bit(loc_addr, ll_addr + 2);
00128             ipv6_neighbour_update_from_na(&cur->ipv6_neighbour_cache, neighbour_entry, NA_S | NA_O | NA_R, ADDR_802_15_4_SHORT , ll_addr);
00129         } else {
00130             ipv6_neighbour_entry_remove(&cur->ipv6_neighbour_cache, neighbour_entry);
00131         }
00132     }
00133 }
00134 
00135 static void thread_nd_coap_notification_callback(int8_t interface_id, const uint8_t ip_addr[16], uint16_t loc_addr, const uint8_t ml_eid[8])
00136 {
00137     protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
00138     if (!cur) {
00139         return;
00140     }
00141 
00142     /* First check to see if we have an existing entry with different RLOC - we need to unicast error
00143      * notification to that old entry if so. */
00144     ipv6_neighbour_t *entry = ipv6_neighbour_lookup(&cur->ipv6_neighbour_cache, ip_addr);
00145     if (entry && entry->ll_type == ADDR_802_15_4_SHORT ) {
00146         uint16_t old_entry_rloc = common_read_16_bit(entry->ll_address + 2);
00147         if (old_entry_rloc != loc_addr) {
00148             uint8_t old_entry_ip[16];
00149             thread_addr_write_mesh_local_16(old_entry_ip, common_read_16_bit(entry->ll_address + 2), cur->thread_info);
00150             tr_warn("Proactive address change %s %04x->%04x", trace_ipv6(ip_addr), old_entry_rloc, loc_addr);
00151             thread_resolution_client_address_error(interface_id, old_entry_ip, ip_addr, ml_eid);
00152         }
00153     }
00154 
00155     /* Now treat as an unsolicited update (by address, because entry may be NULL) */
00156     uint8_t ll_addr[4];
00157     common_write_16_bit(cur->mac_parameters->pan_id, ll_addr + 0);
00158     common_write_16_bit(loc_addr, ll_addr + 2);
00159     ipv6_neighbour_update_unsolicited(&cur->ipv6_neighbour_cache, ip_addr, ADDR_802_15_4_SHORT , ll_addr);
00160 
00161     if (nd_proxy_enabled_for_upstream(cur->id)) {
00162         ipv6_route_add(ip_addr, 128, cur->id, NULL, ROUTE_THREAD_PROXIED_HOST, 3600, 0);
00163     }
00164 }
00165 
00166 static bool thread_nd_coap_transmit(protocol_interface_info_entry_t *cur, ipv6_neighbour_t *entry , uint8_t seq)
00167 {
00168 
00169     if (thread_resolution_client_resolve(cur->id, entry->ip_address, thread_nd_coap_response_callback) < 0) {
00170         goto failed;
00171     }
00172     (void) seq;
00173 
00174     // "In progress" is indicated by returning true
00175     return true;
00176 
00177 failed:
00178     // Failure is indicated by removing the neighbour cache entry,
00179     // and returning true meaning "don't send normal ICMPv6 NS".
00180     ipv6_neighbour_entry_remove(&cur->ipv6_neighbour_cache, entry);
00181     return true;
00182 }
00183 
00184 
00185 bool thread_nd_ns_transmit(protocol_interface_info_entry_t *cur, ipv6_neighbour_t *entry,  bool unicast, uint8_t seq)
00186 {
00187     // neighbor discovery active only for Routers and FEDs
00188     if (cur->thread_info->thread_device_mode != THREAD_DEVICE_MODE_FULL_END_DEVICE &&
00189             cur->thread_info->thread_device_mode != THREAD_DEVICE_MODE_ROUTER) {
00190         return true;
00191     }
00192     if (unicast) {
00193         return thread_nd_probe_transmit(cur, entry);
00194     } else {
00195         return thread_nd_coap_transmit(cur, entry, seq);
00196     }
00197 }
00198 
00199 static mle_neigh_table_entry_t *thread_nd_child_mleid_get(int8_t interface_id, uint8_t *childAddress, uint8_t *mlmeid_ptr)
00200 {
00201     mle_neigh_table_entry_t *entry_temp;
00202     entry_temp = mle_class_get_by_link_address(interface_id, childAddress, ADDR_802_15_4_SHORT );
00203     if (entry_temp) {
00204         if ((entry_temp->mode & MLE_DEV_MASK) == MLE_RFD_DEV) {
00205             memcpy(mlmeid_ptr,entry_temp->mlEid,8);
00206             return entry_temp;
00207         }
00208     }
00209     return NULL;
00210 }
00211 
00212 static int thread_nd_address_query_lookup(int8_t interface_id, const uint8_t target_addr[static 16], uint16_t *addr_out, bool *proxy, uint32_t *last_transaction_time, uint8_t *mleid_ptr)
00213 {
00214     protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
00215     if (!cur) {
00216         return -1;
00217     }
00218 
00219     uint16_t mac16 = mac_helper_mac16_address_get(cur);
00220 
00221     if (addr_is_assigned_to_interface(cur, target_addr)) {
00222         *addr_out = mac16;
00223         memcpy(mleid_ptr, cur->iid_slaac, 8);
00224         *proxy = false;
00225         return 0;
00226     }
00227 
00228     /* Scan IPv6 neighbour cache for registered entries of children */
00229     ns_list_foreach(ipv6_neighbour_t, n, &cur->ipv6_neighbour_cache.list) {
00230         if (n->type == IP_NEIGHBOUR_REGISTERED && addr_ipv6_equal(n->ip_address, target_addr)) {
00231             mle_neigh_table_entry_t *mle_entry;
00232             *addr_out = mac16;
00233             mle_entry = thread_nd_child_mleid_get(interface_id, &n->ll_address[2], mleid_ptr);
00234             if (mle_entry) {
00235                 //Get MLEID from Child
00236                 *last_transaction_time = (protocol_core_monotonic_time - mle_entry->last_contact_time) / 10;  /* Both variables are count of 100ms ticks. */
00237                 *proxy = true;
00238                 return 0;
00239             }
00240         }
00241     }
00242 
00243     // IF we are acting as border router and we have enabled ND proxy. we respond to address
00244     // queries that are not registered to us if we can route those packets out.
00245     /* Verify DHCP Server Status */
00246     bool can_route_of_mesh = false;
00247 
00248     if (!nd_proxy_enabled_for_upstream(interface_id) ) {
00249         //ND proxy not enabled can not answer
00250         return -1;
00251     }
00252 
00253     // TODO needed for eternal border router applications can be removed later
00254     if ( libdhcpv6_server_data_get_by_prefix_and_interfaceid(interface_id, target_addr) ){
00255         can_route_of_mesh = true;
00256     }
00257 
00258     // Check if we are registered as border router in network data.
00259     if(thread_bbr_routing_enabled(cur)) {
00260         can_route_of_mesh = true;
00261     }
00262 
00263     if (thread_extension_bbr_nd_query_process(cur,target_addr)) {
00264         can_route_of_mesh = true;
00265     }
00266 
00267     if (can_route_of_mesh) {
00268         ipv6_route_t *route = ipv6_route_choose_next_hop(target_addr, -1, NULL);
00269         //Respond default route only when we would route it of mesh.
00270         if (route && route->on_link && route->info.interface_id != interface_id) {
00271             *addr_out = mac16;
00272             memcpy(mleid_ptr, cur->iid_slaac, 8);
00273             *proxy = false;
00274             return 0;
00275         }
00276     }
00277 
00278     return -1;
00279 }
00280 
00281 static void thread_nd_address_error(int8_t interface_id, const uint8_t ip_addr[16], const uint8_t ml_eid[8])
00282 {
00283     protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
00284     if (!cur) {
00285         return;
00286     }
00287 
00288     /* Processing for ourselves - if we have the address, and the ML-EID in the
00289      * message is _not_ ours, we delete.
00290      */
00291     if_address_entry_t *addr_entry = addr_get_entry(cur, ip_addr);
00292     if (addr_entry && memcmp(ml_eid, cur->iid_slaac, 8)) {
00293         addr_duplicate_detected(cur, ip_addr);
00294     }
00295 
00296     /* Scan IPv6 neighbour cache for registered entries of children */
00297     ns_list_foreach_safe(ipv6_neighbour_t, n, &cur->ipv6_neighbour_cache.list) {
00298         if (n->type == IP_NEIGHBOUR_REGISTERED && addr_ipv6_equal(n->ip_address, ip_addr)) {
00299             uint8_t child_mleid[8];
00300             mle_neigh_table_entry_t *child = thread_nd_child_mleid_get(interface_id, &n->ll_address[2], child_mleid);
00301             /* If this address belongs to an RFD child, with a different ML-EID, we must send it a duplicate message, and remove the EID */
00302             if (child && memcmp(child_mleid, ml_eid, 8)) {
00303                 uint8_t child_ml_addr[16];
00304                 thread_addr_write_mesh_local_16(child_ml_addr, child->short_adr, cur->thread_info);
00305                 tr_warn("Forwarding address error to child %04x", common_read_16_bit(&n->ll_address[2]));
00306                 thread_resolution_client_address_error(interface_id, child_ml_addr, ip_addr, ml_eid);
00307                 ipv6_neighbour_entry_remove(&cur->ipv6_neighbour_cache, n);
00308             }
00309         }
00310     }
00311 
00312     return;
00313 }
00314 
00315 /* Flush neighbour cache entries pointing at this 16-bit address, or (optionally) its children */
00316 void thread_nd_flush_neighbour_cache_for_short_addr(protocol_interface_info_entry_t *cur, uint16_t flushee, bool children)
00317 {
00318     ns_list_foreach_safe(ipv6_neighbour_t, entry, &cur->ipv6_neighbour_cache.list) {
00319         if (entry->ll_type != ADDR_802_15_4_SHORT  || entry->type != IP_NEIGHBOUR_GARBAGE_COLLECTIBLE) {
00320             continue;
00321         }
00322 
00323         uint16_t n16 = common_read_16_bit(entry->ll_address + 2);
00324         if (flushee == n16 || (children && flushee == thread_router_addr_from_addr(n16))) {
00325             ipv6_neighbour_entry_remove(&cur->ipv6_neighbour_cache, entry);
00326         }
00327     }
00328 }
00329 
00330 static buffer_t *thread_nd_icmp_error_to_mesh_originator(buffer_t *buf, protocol_interface_info_entry_t *cur, const sockaddr_t *ll_src)
00331 {
00332     /* First generate a normal ICMP error (to the IP source) */
00333     buf = icmpv6_error(buf, cur, ICMPV6_TYPE_ERROR_DESTINATION_UNREACH, ICMPV6_CODE_DST_UNREACH_NO_ROUTE, 0);
00334     if (!buf) {
00335         return NULL;
00336     }
00337 
00338     /* Now the messed-up bit. The source gets nothing. This is going to the mesh originator */
00339     /* DST = ML16 derived from the mesh originator address */
00340     memcpy(buf->dst_sa .address , cur->thread_info->threadPrivatePrefixInfo.ulaPrefix, 8);
00341     memcpy(buf->dst_sa .address  + 8, ADDR_SHORT_ADR_SUFFIC, 6);
00342     buf->dst_sa .address [14] = ll_src->address [2];
00343     buf->dst_sa .address [15] = ll_src->address [3];
00344     /* Want 16-bit ML16 source - this should select it if available */
00345     const uint8_t *src = addr_select_source(cur, buf->dst_sa .address , SOCKET_IPV6_PREFER_SRC_6LOWPAN_SHORT);
00346     if (!src) {
00347         return buffer_free(buf);
00348     }
00349     memcpy(buf->src_sa .address , src, 16);
00350 
00351     return buffer_free_route(buf);
00352 }
00353 
00354 /* Called when link layer passes up a unicast packet that was not for our
00355  * link-layer address. Our mesh handlers do this when they see a packet
00356  * addressed to a non-existent child or minimal function device child.
00357  */
00358 buffer_t *thread_nd_snoop(protocol_interface_info_entry_t *cur, buffer_t *buf, const sockaddr_t *ll_dst, const sockaddr_t *ll_src, bool *bounce)
00359 {
00360     /* If snooping, security check hasn't happened yet */
00361     if (buf->options .ll_security_bypass_rx ) {
00362         return buffer_free(buf);
00363     }
00364 
00365     /* We just drop it if it wasn't mesh-addressed (impossible)  */
00366     if (!(buf->options .lowpan_mesh_rx  && ll_src->addr_type  == ADDR_802_15_4_SHORT )) {
00367         return buffer_free(buf);
00368     }
00369 
00370     if (!mle_class_get_by_link_address(cur->id, &ll_dst->address [2], ADDR_802_15_4_SHORT )) {
00371         /* We now know this was a packet for a non-existent child */
00372         goto bounce;
00373     }
00374 
00375     /* Packet must have been mesh-addressed to a minimal-function child. This always */
00376     /* indicates a cache error, unless the IP destination was an ML16 (RLOC16). */
00377     if (!thread_addr_is_mesh_local_16(buf->dst_sa .address , cur) ||
00378         buf->dst_sa .address [14] != ll_dst->address [2] ||
00379         buf->dst_sa .address [15] != ll_dst->address [3]) {
00380         goto bounce;
00381     }
00382 
00383     /* Forward the packet according to IP destination - we've consistency checked
00384      * it is an ML16 matching the original mesh destination, so will get there fine. */
00385     buf->options .ll_not_ours_rx  = false;
00386     return buf;
00387 
00388 bounce:
00389     *bounce = true;
00390     return thread_nd_icmp_error_to_mesh_originator(buf, cur, ll_src);
00391 }
00392 
00393 /* Called when we've determined the packet isn't IP addressed to us, but has okay
00394  * security. Precedes any other checks like forwarding enabled, or destination
00395  * type, scope.
00396  */
00397 buffer_t *thread_nd_special_forwarding(protocol_interface_info_entry_t *cur, buffer_t *buf, const sockaddr_t *ll_src, bool *bounce)
00398 {
00399     /* Funny Thread rule
00400      *
00401      *    A cache error is detected if a device receives a packet containing
00402      *    a 6LoWPAN mesh header[1] and an EID destination IPv6 address where
00403      *    the mesh destination is the device's RLOC16 address [2] but the EID
00404      *    does not belong to the receiver or, if the receiver is a router,
00405      *    the EID has not been registered by any Child of the receiver.
00406      *
00407      *    When a cache error is detected, the receiving device must respond by
00408      *    sending an ICMPv6 Destination Unreachable message with the ICMPv6
00409      *    Code set to 0 (No route to destination) [3] to the packet's mesh source
00410      *
00411      * Return "No route" if on-link destination, received from mesh, and it's not
00412      * for us or a child. Note that we return this even if not a router;
00413      * normally hosts should silently drop wrongly-addressed packets.
00414      *
00415      * (If the addressed child doesn't exist at all, the packet gets sent to
00416      * thread_nd_snoop, generating an error there).
00417      *
00418      * XXX [1] Neighbouring routers optimise out the mesh header, breaking this
00419      * response.
00420      *
00421      * XXX [1b] Children also optimise out mesh headers, so a full-function child
00422      * that has a stale resolution of a minimal device to our router address needs
00423      * to get a failure response.
00424      *
00425      * XXX [2] Mesh destination may have been RLOC16 of a child, and we have snooped
00426      * because they're MTD.
00427      *
00428      * XXX [3] "No route (0)" is a silly choice of code; "address unreachable (3)"
00429      * would make more sense.
00430      */
00431 
00432     if (ll_src->addr_type  != ADDR_802_15_4_SHORT ) {
00433         return buf;
00434     }
00435 
00436     mle_neigh_table_entry_t *entry = mle_class_get_by_link_address(cur->id, &ll_src->address [2], ADDR_802_15_4_SHORT );
00437 
00438     /* Due to note 1 and 1b above, full-function children / neighbor routers
00439      * who did resolve to an RLOC16 may have optimised out the mesh header.
00440      * So we check for either the mesh header being present, or it coming
00441      * from a full-function device (FFD) neighbor.
00442      *
00443      * (If it comes from a MTD child without a mesh header we always
00444      * forward as normal, attempting address resolution if necessary.
00445      * If it comes from a child with a mesh header and the IP destination
00446      * is not in our neighbour cache, we need to send the child an error
00447      * to clear its cache.)
00448      */
00449     if (!(buf->options .lowpan_mesh_rx  || (entry && (entry->mode & MLE_DEV_MASK) == MLE_FFD_DEV))) {
00450         return buf;
00451     }
00452 
00453     /* Link-local and ML16 addresses are not EIDs, so no error generation */
00454     if (addr_is_ipv6_link_local(buf->dst_sa .address ) || thread_addr_is_mesh_local_16(buf->dst_sa .address , cur)) {
00455         return buf;
00456     }
00457 
00458     buffer_routing_info_t *route = ipv6_buffer_route(buf);
00459     if (!route) {
00460         return buf;
00461     }
00462 
00463     if (route->route_info.interface_id != cur->id) {
00464         return buf;
00465     }
00466 
00467     /* On-link test - only perform this check for on-link prefixes - those will have next_hop == destination */
00468     /* Being on-link is what tells us an address is an "EID" rather than an arbitrary global IPv6 address */
00469     if (!addr_ipv6_equal(route->route_info.next_hop_addr, buf->dst_sa .address )) {
00470         return buf;
00471     }
00472 
00473      /* If it was addressed to us as an IP router, it's okay if the packet is for a child */
00474     if (thread_i_am_router(cur)) {
00475         //Check Registered Addresses
00476         ns_list_foreach(ipv6_neighbour_t, n, &cur->ipv6_neighbour_cache.list) {
00477             if (n->type == IP_NEIGHBOUR_REGISTERED
00478                     && memcmp(n->ip_address, buf->dst_sa .address , 16) == 0) {
00479                 return buf;
00480             }
00481         }
00482     }
00483 
00484     *bounce = true;
00485     return thread_nd_icmp_error_to_mesh_originator(buf, cur, ll_src);
00486 }
00487 
00488 /* The handler for the packets transmitted above (draft-kelsey-thread-network-data-00) */
00489 buffer_t *thread_nd_icmp_handler(protocol_interface_info_entry_t *cur, buffer_t *buf, bool *bounce)
00490 {
00491     (void) bounce;
00492     /* Try to make sure we specifically "such an ICMP message", not normal ones */
00493     if (!thread_addr_is_mesh_local_16(buf->dst_sa .address , cur) || !thread_addr_is_mesh_local_16(buf->src_sa .address , cur)) {
00494         return buf;
00495     }
00496 
00497     if (buf->options .type  != ICMPV6_TYPE_ERROR_DESTINATION_UNREACH) {
00498         return buf;
00499     }
00500 
00501     if (buf->options .code  != ICMPV6_CODE_DST_UNREACH_NO_ROUTE) {
00502         return buf;
00503     }
00504 
00505     /* Make sure we have the original destination address from invoking packet */
00506     if (buffer_data_length(buf) < 4 + 40) {
00507         return buf;
00508     }
00509 
00510     const uint8_t *targetIP = buffer_data_pointer(buf) + 4 + 24;
00511 
00512     /* Try to look up the ML64 entry in the cache. */
00513     ipv6_neighbour_t *n = ipv6_neighbour_lookup(&cur->ipv6_neighbour_cache, targetIP);
00514     if (!n || n->ll_type != ADDR_802_15_4_SHORT  || n->type != IP_NEIGHBOUR_GARBAGE_COLLECTIBLE) {
00515         return buf;
00516     }
00517 
00518     /* Invalidate that ML64 entry if its 16-bit address is equal to, or a child
00519      * of, the source of the ICMP message. If it doesn't match, suggests
00520      * a bogus packet - exit now.
00521      */
00522     uint16_t icmp16 = common_read_16_bit(buf->src_sa .address  + 14);
00523     uint16_t entry16 = common_read_16_bit(n->ll_address + 2);
00524     if (!thread_addr_is_equal_or_child(icmp16, entry16)) {
00525         return buf;
00526     }
00527 
00528     ipv6_neighbour_entry_remove(&cur->ipv6_neighbour_cache, n);
00529 
00530     return buf;
00531 }
00532 
00533 int thread_nd_address_registration(protocol_interface_info_entry_t *cur, const uint8_t *ipv6Address, uint16_t mac16, uint16_t panId, const uint8_t *mac64)
00534 {
00535     ipv6_neighbour_t *neigh;
00536     uint8_t ll_address[4];
00537     common_write_16_bit(panId, ll_address + 0);
00538     common_write_16_bit(mac16, ll_address + 2);
00539     neigh = ipv6_neighbour_lookup_or_create(&cur->ipv6_neighbour_cache, ipv6Address);
00540     if (!neigh) {
00541         return -1;
00542     }
00543 
00544     uint8_t *nce_eui64 = ipv6_neighbour_eui64(&cur->ipv6_neighbour_cache, neigh);
00545     /*if (neigh->state != IP_NEIGHBOUR_NEW)
00546        {
00547               // Worry about this later
00548               // Compare mac64 to nce_eui64 to spot duplicates
00549        }
00550        else*/
00551     {
00552         /* New entry */
00553         memcpy(nce_eui64, mac64, 8);
00554     }
00555     /* Set the LL address, ensure it's marked STALE */
00556     ipv6_neighbour_entry_update_unsolicited(&cur->ipv6_neighbour_cache, neigh, ADDR_802_15_4_SHORT , ll_address);
00557     neigh->type = IP_NEIGHBOUR_REGISTERED;
00558     neigh->lifetime = 0xffffffff; //Set Infinite
00559     ipv6_neighbour_set_state(&cur->ipv6_neighbour_cache, neigh, IP_NEIGHBOUR_STALE);
00560     return 0;
00561 }
00562 
00563 void thread_nd_address_remove(protocol_interface_info_entry_t *cur_interface, addrtype_t ll_type, const uint8_t *ll_address)
00564 {
00565     ns_list_foreach_safe(ipv6_neighbour_t, cur, &cur_interface->ipv6_neighbour_cache.list) {
00566         if ((cur->type == IP_NEIGHBOUR_REGISTERED || cur->type == IP_NEIGHBOUR_TENTATIVE) && ipv6_neighbour_ll_addr_match(cur, ll_type, ll_address)) {
00567             ipv6_neighbour_entry_remove(&cur_interface->ipv6_neighbour_cache, cur);
00568         }
00569     }
00570 }
00571 
00572 int thread_nd_map_anycast_address(protocol_interface_info_entry_t *cur, uint16_t *addr16)
00573 {
00574     // Nothing implemented for now
00575     uint16_t anycastAddress = *addr16;
00576     if(anycastAddress == 0xfc00) {
00577         // this is leader anycast address
00578         *addr16 = thread_router_addr_from_id(cur->thread_info->thread_leader_data->leaderRouterId);
00579         return 0;
00580     }
00581     if ((anycastAddress & 0xfff0) == 0xfc00) {
00582         // Check DHCPv6 anycast address mapping
00583         uint8_t context = anycastAddress;
00584         if (thread_nd_dhcp_anycast_address_mapping_from_network_data(&cur->thread_info->networkDataStorage, addr16, context)) {
00585             return 0;
00586         }
00587     }
00588 
00589     if ((anycastAddress & 0xfff0) == 0xfc10 || (anycastAddress & 0xfff0) == 0xfc20) {
00590         // service mapping to anycast address
00591         uint8_t S_id = anycastAddress & 0x0f;
00592         if (thread_nd_service_anycast_address_mapping_from_network_data(&cur->thread_info->networkDataStorage, addr16, S_id)) {
00593             return 0;
00594         }
00595     }
00596 
00597     if ((anycastAddress & 0xfff8) == 0xfc30) {
00598         // Commissioner anycast address mapping
00599         if (!cur->thread_info->registered_commissioner.commissioner_valid) {
00600             return -1;
00601         }
00602         if ( (anycastAddress & 0x0007) != cur->thread_info->registered_commissioner.session_id % 8 ) {
00603             return -1;
00604         }
00605         *addr16 = common_read_16_bit(cur->thread_info->registered_commissioner.border_router_address + 14);
00606         return 0;
00607     }
00608     if (thread_extension_aloc_map(cur,addr16)) {
00609         return 0;
00610     }
00611 
00612     return -1;
00613 }
00614 
00615 #endif //HAVE_THREAD_NEIGHBOR_DISCOVERY
00616 #endif //HAVE_THREAD
00617