nes-proj/core/net/ipv6/uip-ds6-route.c

667 lines
20 KiB
C

/*
* Copyright (c) 2012, Thingsquare, http://www.thingsquare.com/.
* 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 copyright holder 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 COPYRIGHT HOLDERS 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
* COPYRIGHT HOLDER 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.
*
*/
/**
* \addtogroup uip6
* @{
*/
/**
* \file
* Routing table manipulation
*/
#include "net/ipv6/uip-ds6.h"
#include "net/ip/uip.h"
#include "lib/list.h"
#include "lib/memb.h"
#include "net/nbr-table.h"
#include <string.h>
/* A configurable function called after adding a new neighbor as next hop */
#ifdef NETSTACK_CONF_ROUTING_NEIGHBOR_ADDED_CALLBACK
void NETSTACK_CONF_ROUTING_NEIGHBOR_ADDED_CALLBACK(const linkaddr_t *addr);
#endif /* NETSTACK_CONF_ROUTING_NEIGHBOR_ADDED_CALLBACK */
/* A configurable function called after removing a next hop neighbor */
#ifdef NETSTACK_CONF_ROUTING_NEIGHBOR_REMOVED_CALLBACK
void NETSTACK_CONF_ROUTING_NEIGHBOR_REMOVED_CALLBACK(const linkaddr_t *addr);
#endif /* NETSTACK_CONF_ROUTING_NEIGHBOR_REMOVED_CALLBACK */
/* The nbr_routes holds a neighbor table to be able to maintain
information about what routes go through what neighbor. This
neighbor table is registered with the central nbr-table repository
so that it will be maintained along with the rest of the neighbor
tables in the system. */
NBR_TABLE_GLOBAL(struct uip_ds6_route_neighbor_routes, nbr_routes);
MEMB(neighborroutememb, struct uip_ds6_route_neighbor_route, UIP_DS6_ROUTE_NB);
/* Each route is repressented by a uip_ds6_route_t structure and
memory for each route is allocated from the routememb memory
block. These routes are maintained on the routelist. */
LIST(routelist);
MEMB(routememb, uip_ds6_route_t, UIP_DS6_ROUTE_NB);
/* Default routes are held on the defaultrouterlist and their
structures are allocated from the defaultroutermemb memory block.*/
LIST(defaultrouterlist);
MEMB(defaultroutermemb, uip_ds6_defrt_t, UIP_DS6_DEFRT_NB);
#if UIP_DS6_NOTIFICATIONS
LIST(notificationlist);
#endif
static int num_routes = 0;
#undef DEBUG
#define DEBUG DEBUG_NONE
#include "net/ip/uip-debug.h"
static void rm_routelist_callback(nbr_table_item_t *ptr);
/*---------------------------------------------------------------------------*/
#if DEBUG != DEBUG_NONE
static void
assert_nbr_routes_list_sane(void)
{
uip_ds6_route_t *r;
int count;
/* Check if the route list has an infinite loop. */
for(r = uip_ds6_route_head(),
count = 0;
r != NULL &&
count < UIP_DS6_ROUTE_NB * 2;
r = uip_ds6_route_next(r),
count++);
if(count > UIP_DS6_ROUTE_NB) {
printf("uip-ds6-route.c: assert_nbr_routes_list_sane route list is in infinite loop\n");
}
/* Make sure that the route list has as many entries as the
num_routes vairable. */
if(count < num_routes) {
printf("uip-ds6-route.c: assert_nbr_routes_list_sane too few entries on route list: should be %d, is %d, max %d\n",
num_routes, count, UIP_CONF_MAX_ROUTES);
}
}
#endif /* DEBUG != DEBUG_NONE */
/*---------------------------------------------------------------------------*/
#if UIP_DS6_NOTIFICATIONS
static void
call_route_callback(int event, uip_ipaddr_t *route,
uip_ipaddr_t *nexthop)
{
int num;
struct uip_ds6_notification *n;
for(n = list_head(notificationlist);
n != NULL;
n = list_item_next(n)) {
if(event == UIP_DS6_NOTIFICATION_DEFRT_ADD ||
event == UIP_DS6_NOTIFICATION_DEFRT_RM) {
num = list_length(defaultrouterlist);
} else {
num = num_routes;
}
n->callback(event, route, nexthop, num);
}
}
/*---------------------------------------------------------------------------*/
void
uip_ds6_notification_add(struct uip_ds6_notification *n,
uip_ds6_notification_callback c)
{
if(n != NULL && c != NULL) {
n->callback = c;
list_add(notificationlist, n);
}
}
/*---------------------------------------------------------------------------*/
void
uip_ds6_notification_rm(struct uip_ds6_notification *n)
{
list_remove(notificationlist, n);
}
#endif
/*---------------------------------------------------------------------------*/
void
uip_ds6_route_init(void)
{
memb_init(&routememb);
list_init(routelist);
nbr_table_register(nbr_routes,
(nbr_table_callback *)rm_routelist_callback);
memb_init(&defaultroutermemb);
list_init(defaultrouterlist);
#if UIP_DS6_NOTIFICATIONS
list_init(notificationlist);
#endif
}
/*---------------------------------------------------------------------------*/
static uip_lladdr_t *
uip_ds6_route_nexthop_lladdr(uip_ds6_route_t *route)
{
if(route != NULL) {
return (uip_lladdr_t *)nbr_table_get_lladdr(nbr_routes,
route->neighbor_routes);
} else {
return NULL;
}
}
/*---------------------------------------------------------------------------*/
uip_ipaddr_t *
uip_ds6_route_nexthop(uip_ds6_route_t *route)
{
if(route != NULL) {
return uip_ds6_nbr_ipaddr_from_lladdr(uip_ds6_route_nexthop_lladdr(route));
} else {
return NULL;
}
}
/*---------------------------------------------------------------------------*/
uip_ds6_route_t *
uip_ds6_route_head(void)
{
return list_head(routelist);
}
/*---------------------------------------------------------------------------*/
uip_ds6_route_t *
uip_ds6_route_next(uip_ds6_route_t *r)
{
if(r != NULL) {
uip_ds6_route_t *n = list_item_next(r);
return n;
}
return NULL;
}
/*---------------------------------------------------------------------------*/
int
uip_ds6_route_is_nexthop(const uip_lladdr_t *lladdr)
{
return nbr_table_get_from_lladdr(nbr_routes, (linkaddr_t *)lladdr) != NULL;
}
/*---------------------------------------------------------------------------*/
int
uip_ds6_route_num_routes(void)
{
return num_routes;
}
/*---------------------------------------------------------------------------*/
uip_ds6_route_t *
uip_ds6_route_lookup(uip_ipaddr_t *addr)
{
uip_ds6_route_t *r;
uip_ds6_route_t *found_route;
uint8_t longestmatch;
PRINTF("uip-ds6-route: Looking up route for ");
PRINT6ADDR(addr);
PRINTF("\n");
found_route = NULL;
longestmatch = 0;
for(r = uip_ds6_route_head();
r != NULL;
r = uip_ds6_route_next(r)) {
if(r->length >= longestmatch &&
uip_ipaddr_prefixcmp(addr, &r->ipaddr, r->length)) {
longestmatch = r->length;
found_route = r;
/* check if total match - e.g. all 128 bits do match */
if(longestmatch == 128) {
break;
}
}
}
if(found_route != NULL) {
PRINTF("uip-ds6-route: Found route: ");
PRINT6ADDR(addr);
PRINTF(" via ");
PRINT6ADDR(uip_ds6_route_nexthop(found_route));
PRINTF("\n");
} else {
PRINTF("uip-ds6-route: No route found\n");
}
if(found_route != NULL && found_route != list_head(routelist)) {
/* If we found a route, we put it at the start of the routeslist
list. The list is ordered by how recently we looked them up:
the least recently used route will be at the end of the
list - for fast lookups (assuming multiple packets to the same node). */
list_remove(routelist, found_route);
list_push(routelist, found_route);
}
return found_route;
}
/*---------------------------------------------------------------------------*/
uip_ds6_route_t *
uip_ds6_route_add(uip_ipaddr_t *ipaddr, uint8_t length,
uip_ipaddr_t *nexthop)
{
uip_ds6_route_t *r;
struct uip_ds6_route_neighbor_route *nbrr;
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
/* Get link-layer address of next hop, make sure it is in neighbor table */
const uip_lladdr_t *nexthop_lladdr = uip_ds6_nbr_lladdr_from_ipaddr(nexthop);
if(nexthop_lladdr == NULL) {
PRINTF("uip_ds6_route_add: neighbor link-local address unknown for ");
PRINT6ADDR(nexthop);
PRINTF("\n");
return NULL;
}
/* First make sure that we don't add a route twice. If we find an
existing route for our destination, we'll delete the old
one first. */
r = uip_ds6_route_lookup(ipaddr);
if(r != NULL) {
uip_ipaddr_t *current_nexthop;
current_nexthop = uip_ds6_route_nexthop(r);
if(current_nexthop != NULL && uip_ipaddr_cmp(nexthop, current_nexthop)) {
/* no need to update route - already correct! */
return r;
}
PRINTF("uip_ds6_route_add: old route for ");
PRINT6ADDR(ipaddr);
PRINTF(" found, deleting it\n");
uip_ds6_route_rm(r);
}
{
struct uip_ds6_route_neighbor_routes *routes;
/* If there is no routing entry, create one. We first need to
check if we have room for this route. If not, we remove the
least recently used one we have. */
if(uip_ds6_route_num_routes() == UIP_DS6_ROUTE_NB) {
uip_ds6_route_t *oldest;
oldest = NULL;
#if UIP_DS6_ROUTE_REMOVE_LEAST_RECENTLY_USED
/* Removing the oldest route entry from the route table. The
least recently used route is the first route on the list. */
oldest = list_tail(routelist);
#endif
if(oldest == NULL) {
return NULL;
}
PRINTF("uip_ds6_route_add: dropping route to ");
PRINT6ADDR(&oldest->ipaddr);
PRINTF("\n");
uip_ds6_route_rm(oldest);
}
/* Every neighbor on our neighbor table holds a struct
uip_ds6_route_neighbor_routes which holds a list of routes that
go through the neighbor. We add our route entry to this list.
We first check to see if we already have this neighbor in our
nbr_route table. If so, the neighbor already has a route entry
list.
*/
routes = nbr_table_get_from_lladdr(nbr_routes,
(linkaddr_t *)nexthop_lladdr);
if(routes == NULL) {
/* If the neighbor did not have an entry in our neighbor table,
we create one. The nbr_table_add_lladdr() function returns a
pointer to a pointer that we may use for our own purposes. We
initialize this pointer with the list of routing entries that
are attached to this neighbor. */
routes = nbr_table_add_lladdr(nbr_routes,
(linkaddr_t *)nexthop_lladdr);
if(routes == NULL) {
/* This should not happen, as we explicitly deallocated one
route table entry above. */
PRINTF("uip_ds6_route_add: could not allocate neighbor table entry\n");
return NULL;
}
LIST_STRUCT_INIT(routes, route_list);
#ifdef NETSTACK_CONF_ROUTING_NEIGHBOR_ADDED_CALLBACK
NETSTACK_CONF_ROUTING_NEIGHBOR_ADDED_CALLBACK((const linkaddr_t *)nexthop_lladdr);
#endif
}
/* Allocate a routing entry and populate it. */
r = memb_alloc(&routememb);
if(r == NULL) {
/* This should not happen, as we explicitly deallocated one
route table entry above. */
PRINTF("uip_ds6_route_add: could not allocate route\n");
return NULL;
}
/* add new routes first - assuming that there is a reason to add this
and that there is a packet coming soon. */
list_push(routelist, r);
nbrr = memb_alloc(&neighborroutememb);
if(nbrr == NULL) {
/* This should not happen, as we explicitly deallocated one
route table entry above. */
PRINTF("uip_ds6_route_add: could not allocate neighbor route list entry\n");
memb_free(&routememb, r);
return NULL;
}
nbrr->route = r;
/* Add the route to this neighbor */
list_add(routes->route_list, nbrr);
r->neighbor_routes = routes;
num_routes++;
PRINTF("uip_ds6_route_add num %d\n", num_routes);
/* lock this entry so that nexthop is not removed */
nbr_table_lock(nbr_routes, routes);
}
uip_ipaddr_copy(&(r->ipaddr), ipaddr);
r->length = length;
#ifdef UIP_DS6_ROUTE_STATE_TYPE
memset(&r->state, 0, sizeof(UIP_DS6_ROUTE_STATE_TYPE));
#endif
PRINTF("uip_ds6_route_add: adding route: ");
PRINT6ADDR(ipaddr);
PRINTF(" via ");
PRINT6ADDR(nexthop);
PRINTF("\n");
ANNOTATE("#L %u 1;blue\n", nexthop->u8[sizeof(uip_ipaddr_t) - 1]);
#if UIP_DS6_NOTIFICATIONS
call_route_callback(UIP_DS6_NOTIFICATION_ROUTE_ADD, ipaddr, nexthop);
#endif
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
return r;
}
/*---------------------------------------------------------------------------*/
void
uip_ds6_route_rm(uip_ds6_route_t *route)
{
struct uip_ds6_route_neighbor_route *neighbor_route;
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
if(route != NULL && route->neighbor_routes != NULL) {
PRINTF("uip_ds6_route_rm: removing route: ");
PRINT6ADDR(&route->ipaddr);
PRINTF("\n");
/* Remove the route from the route list */
list_remove(routelist, route);
/* Find the corresponding neighbor_route and remove it. */
for(neighbor_route = list_head(route->neighbor_routes->route_list);
neighbor_route != NULL && neighbor_route->route != route;
neighbor_route = list_item_next(neighbor_route));
if(neighbor_route == NULL) {
PRINTF("uip_ds6_route_rm: neighbor_route was NULL for ");
uip_debug_ipaddr_print(&route->ipaddr);
PRINTF("\n");
}
list_remove(route->neighbor_routes->route_list, neighbor_route);
if(list_head(route->neighbor_routes->route_list) == NULL) {
/* If this was the only route using this neighbor, remove the
neighbor from the table - this implicitly unlocks nexthop */
#if (DEBUG) & DEBUG_ANNOTATE
uip_ipaddr_t *nexthop = uip_ds6_route_nexthop(route);
if(nexthop != NULL) {
ANNOTATE("#L %u 0\n", nexthop->u8[sizeof(uip_ipaddr_t) - 1]);
}
#endif /* (DEBUG) & DEBUG_ANNOTATE */
PRINTF("uip_ds6_route_rm: removing neighbor too\n");
nbr_table_remove(nbr_routes, route->neighbor_routes->route_list);
#ifdef NETSTACK_CONF_ROUTING_NEIGHBOR_REMOVED_CALLBACK
NETSTACK_CONF_ROUTING_NEIGHBOR_REMOVED_CALLBACK(
(const linkaddr_t *)nbr_table_get_lladdr(nbr_routes, route->neighbor_routes->route_list));
#endif
}
memb_free(&routememb, route);
memb_free(&neighborroutememb, neighbor_route);
num_routes--;
PRINTF("uip_ds6_route_rm num %d\n", num_routes);
#if UIP_DS6_NOTIFICATIONS
call_route_callback(UIP_DS6_NOTIFICATION_ROUTE_RM,
&route->ipaddr, uip_ds6_route_nexthop(route));
#endif
}
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
return;
}
/*---------------------------------------------------------------------------*/
static void
rm_routelist(struct uip_ds6_route_neighbor_routes *routes)
{
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
PRINTF("uip_ds6_route_rm_routelist\n");
if(routes != NULL && routes->route_list != NULL) {
struct uip_ds6_route_neighbor_route *r;
r = list_head(routes->route_list);
while(r != NULL) {
uip_ds6_route_rm(r->route);
r = list_head(routes->route_list);
}
nbr_table_remove(nbr_routes, routes);
}
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
}
/*---------------------------------------------------------------------------*/
static void
rm_routelist_callback(nbr_table_item_t *ptr)
{
rm_routelist((struct uip_ds6_route_neighbor_routes *)ptr);
}
/*---------------------------------------------------------------------------*/
void
uip_ds6_route_rm_by_nexthop(uip_ipaddr_t *nexthop)
{
/* Get routing entry list of this neighbor */
const uip_lladdr_t *nexthop_lladdr;
struct uip_ds6_route_neighbor_routes *routes;
nexthop_lladdr = uip_ds6_nbr_lladdr_from_ipaddr(nexthop);
routes = nbr_table_get_from_lladdr(nbr_routes,
(linkaddr_t *)nexthop_lladdr);
rm_routelist(routes);
}
/*---------------------------------------------------------------------------*/
uip_ds6_defrt_t *
uip_ds6_defrt_add(uip_ipaddr_t *ipaddr, unsigned long interval)
{
uip_ds6_defrt_t *d;
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
PRINTF("uip_ds6_defrt_add\n");
d = uip_ds6_defrt_lookup(ipaddr);
if(d == NULL) {
d = memb_alloc(&defaultroutermemb);
if(d == NULL) {
PRINTF("uip_ds6_defrt_add: could not add default route to ");
PRINT6ADDR(ipaddr);
PRINTF(", out of memory\n");
return NULL;
} else {
PRINTF("uip_ds6_defrt_add: adding default route to ");
PRINT6ADDR(ipaddr);
PRINTF("\n");
}
list_push(defaultrouterlist, d);
}
uip_ipaddr_copy(&d->ipaddr, ipaddr);
if(interval != 0) {
stimer_set(&d->lifetime, interval);
d->isinfinite = 0;
} else {
d->isinfinite = 1;
}
ANNOTATE("#L %u 1\n", ipaddr->u8[sizeof(uip_ipaddr_t) - 1]);
#if UIP_DS6_NOTIFICATIONS
call_route_callback(UIP_DS6_NOTIFICATION_DEFRT_ADD, ipaddr, ipaddr);
#endif
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
return d;
}
/*---------------------------------------------------------------------------*/
void
uip_ds6_defrt_rm(uip_ds6_defrt_t *defrt)
{
uip_ds6_defrt_t *d;
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
/* Make sure that the defrt is in the list before we remove it. */
for(d = list_head(defaultrouterlist);
d != NULL;
d = list_item_next(d)) {
if(d == defrt) {
PRINTF("Removing default route\n");
list_remove(defaultrouterlist, defrt);
memb_free(&defaultroutermemb, defrt);
ANNOTATE("#L %u 0\n", defrt->ipaddr.u8[sizeof(uip_ipaddr_t) - 1]);
#if UIP_DS6_NOTIFICATIONS
call_route_callback(UIP_DS6_NOTIFICATION_DEFRT_RM,
&defrt->ipaddr, &defrt->ipaddr);
#endif
return;
}
}
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
}
/*---------------------------------------------------------------------------*/
uip_ds6_defrt_t *
uip_ds6_defrt_lookup(uip_ipaddr_t *ipaddr)
{
uip_ds6_defrt_t *d;
for(d = list_head(defaultrouterlist);
d != NULL;
d = list_item_next(d)) {
if(uip_ipaddr_cmp(&d->ipaddr, ipaddr)) {
return d;
}
}
return NULL;
}
/*---------------------------------------------------------------------------*/
uip_ipaddr_t *
uip_ds6_defrt_choose(void)
{
uip_ds6_defrt_t *d;
uip_ds6_nbr_t *bestnbr;
uip_ipaddr_t *addr;
addr = NULL;
for(d = list_head(defaultrouterlist);
d != NULL;
d = list_item_next(d)) {
PRINTF("Defrt, IP address ");
PRINT6ADDR(&d->ipaddr);
PRINTF("\n");
bestnbr = uip_ds6_nbr_lookup(&d->ipaddr);
if(bestnbr != NULL && bestnbr->state != NBR_INCOMPLETE) {
PRINTF("Defrt found, IP address ");
PRINT6ADDR(&d->ipaddr);
PRINTF("\n");
return &d->ipaddr;
} else {
addr = &d->ipaddr;
PRINTF("Defrt INCOMPLETE found, IP address ");
PRINT6ADDR(&d->ipaddr);
PRINTF("\n");
}
}
return addr;
}
/*---------------------------------------------------------------------------*/
void
uip_ds6_defrt_periodic(void)
{
uip_ds6_defrt_t *d;
d = list_head(defaultrouterlist);
while(d != NULL) {
if(!d->isinfinite &&
stimer_expired(&d->lifetime)) {
PRINTF("uip_ds6_defrt_periodic: defrt lifetime expired\n");
uip_ds6_defrt_rm(d);
d = list_head(defaultrouterlist);
} else {
d = list_item_next(d);
}
}
}
/*---------------------------------------------------------------------------*/
/** @} */