Fixed a few bugs in the route handling code. While bughunting, rewrote parts of the code to make its intention clearer. Also added a bunch of comments to make the logic of the code more evident.

This commit is contained in:
Adam Dunkels 2013-08-12 00:22:21 +02:00 committed by Simon Duquennoy
parent 8dc4e46968
commit bfd7e5f25b
2 changed files with 176 additions and 40 deletions

View file

@ -40,11 +40,22 @@
#include <string.h> #include <string.h>
void uip_ds6_route_rm_routelist(list_t nbr_table_get_from_lladdr); /* 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(struct uip_ds6_route_neighbor_routes, nbr_routes);
NBR_TABLE(uip_ds6_route_t *, nbr_routes); /* 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 lists of route entries that
are attached to each neighbor, via the nbr_routes neighbor
table. */
MEMB(routememb, uip_ds6_route_t, UIP_DS6_ROUTE_NB); 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); LIST(defaultrouterlist);
MEMB(defaultroutermemb, uip_ds6_defrt_t, UIP_DS6_DEFRT_NB); MEMB(defaultroutermemb, uip_ds6_defrt_t, UIP_DS6_DEFRT_NB);
@ -58,6 +69,35 @@ static int num_routes = 0;
#define DEBUG DEBUG_NONE #define DEBUG DEBUG_NONE
#include "net/uip-debug.h" #include "net/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;
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 #if UIP_DS6_NOTIFICATIONS
static void static void
@ -100,7 +140,8 @@ void
uip_ds6_route_init(void) uip_ds6_route_init(void)
{ {
memb_init(&routememb); memb_init(&routememb);
nbr_table_register(nbr_routes, (nbr_table_callback *)uip_ds6_route_rm_routelist); nbr_table_register(nbr_routes,
(nbr_table_callback *)rm_routelist_callback);
memb_init(&defaultroutermemb); memb_init(&defaultroutermemb);
list_init(defaultrouterlist); list_init(defaultrouterlist);
@ -114,7 +155,7 @@ static uip_lladdr_t *
uip_ds6_route_nexthop_lladdr(uip_ds6_route_t *route) uip_ds6_route_nexthop_lladdr(uip_ds6_route_t *route)
{ {
if(route != NULL) { if(route != NULL) {
return (uip_lladdr_t *)nbr_table_get_lladdr(nbr_routes, route->route_list); return (uip_lladdr_t *)nbr_table_get_lladdr(nbr_routes, route->routes);
} else { } else {
return NULL; return NULL;
} }
@ -133,9 +174,14 @@ uip_ds6_route_nexthop(uip_ds6_route_t *route)
uip_ds6_route_t * uip_ds6_route_t *
uip_ds6_route_head(void) uip_ds6_route_head(void)
{ {
list_t nbr_route_list = nbr_table_head(nbr_routes); struct uip_ds6_route_neighbor_routes *routes;
if(nbr_route_list != NULL) {
return list_head((list_t)nbr_route_list); routes = (struct uip_ds6_route_neighbor_routes *)nbr_table_head(nbr_routes);
if(routes != NULL) {
if(list_head(routes->route_list) == NULL) {
PRINTF("uip_ds6_route_head lead_head(nbr_route_list) is NULL\n");
}
return list_head(routes->route_list);
} else { } else {
return NULL; return NULL;
} }
@ -149,9 +195,11 @@ uip_ds6_route_next(uip_ds6_route_t *r)
if(n != NULL) { if(n != NULL) {
return n; return n;
} else { } else {
list_t nbr_route_list = nbr_table_next(nbr_routes, r->route_list); struct uip_ds6_route_neighbor_routes *routes;
if(nbr_route_list != NULL) { routes = (struct uip_ds6_route_neighbor_routes *)
return list_head((list_t)nbr_route_list); nbr_table_next(nbr_routes, r->routes);
if(routes != NULL) {
return list_head(routes->route_list);
} }
} }
} }
@ -207,7 +255,10 @@ uip_ds6_route_add(uip_ipaddr_t *ipaddr, uint8_t length,
uip_ipaddr_t *nexthop) uip_ipaddr_t *nexthop)
{ {
uip_ds6_route_t *r; uip_ds6_route_t *r;
list_t nbr_route_list;
#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 */ /* Get link-layer address of next hop, make sure it is in neighbor table */
uip_lladdr_t *nexthop_lladdr = uip_ds6_nbr_lladdr_from_ipaddr(nexthop); uip_lladdr_t *nexthop_lladdr = uip_ds6_nbr_lladdr_from_ipaddr(nexthop);
@ -218,9 +269,6 @@ uip_ds6_route_add(uip_ipaddr_t *ipaddr, uint8_t length,
return NULL; return NULL;
} }
/* Get routing entry list of this neighbor */
nbr_route_list = nbr_table_get_from_lladdr(nbr_routes, (rimeaddr_t *)nexthop_lladdr);
/* First make sure that we don't add a route twice. If we find an /* First make sure that we don't add a route twice. If we find an
existing route for our destination, we'll just update the old existing route for our destination, we'll just update the old
one. */ one. */
@ -230,34 +278,56 @@ uip_ds6_route_add(uip_ipaddr_t *ipaddr, uint8_t length,
PRINT6ADDR(ipaddr); PRINT6ADDR(ipaddr);
PRINTF("\n"); PRINTF("\n");
} else { } else {
struct uip_ds6_route_neighbor_routes *routes;
/* If there is no routing entry, create one */ /* If there is no routing entry, create one */
if(nbr_route_list == NULL) {
nbr_route_list = nbr_table_add_lladdr(nbr_routes, (rimeaddr_t *)nexthop_lladdr); /* Every neighbor on our neighbor table holds a struct
if(nbr_route_list == NULL) { uip_ds6_route_neighbor_routes which holds a list of routes that
PRINTF("uip_ds6_route_add: could not allocate memory (route list) for new route to "); 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,
(rimeaddr_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,
(rimeaddr_t *)nexthop_lladdr);
if(routes == NULL) {
PRINTF("uip_ds6_route_add: could not allocate a neighbor table entri for new route to ");
PRINT6ADDR(ipaddr); PRINT6ADDR(ipaddr);
PRINTF(", dropping it\n"); PRINTF(", dropping it\n");
return NULL; return NULL;
} }
list_init((list_t)nbr_route_list); LIST_STRUCT_INIT(routes, route_list);
} }
/* Allocate a routing entry and add the route to the list */ /* Allocate a routing entry and populate it. */
r = memb_alloc(&routememb); r = memb_alloc(&routememb);
if(r == NULL) { if(r == NULL) {
PRINTF("uip_ds6_route_add: could not allocate memory for new route to "); PRINTF("uip_ds6_route_add: could not allocate memory for new route to ");
PRINT6ADDR(ipaddr); PRINT6ADDR(ipaddr);
PRINTF(", dropping it\n"); PRINTF(", dropping it\n");
return NULL; return NULL;
} }
/* Add the route to this neighbor */ /* Add the route to this neighbor */
list_add((list_t)nbr_route_list, r); list_add(routes->route_list, r);
num_routes++; num_routes++;
PRINTF("uip_ds6_route_add num %d\n", num_routes); PRINTF("uip_ds6_route_add num %d\n", num_routes);
r->routes = routes;
} }
r->route_list = nbr_route_list;
uip_ipaddr_copy(&(r->ipaddr), ipaddr); uip_ipaddr_copy(&(r->ipaddr), ipaddr);
r->length = length; r->length = length;
@ -276,6 +346,9 @@ uip_ds6_route_add(uip_ipaddr_t *ipaddr, uint8_t length,
call_route_callback(UIP_DS6_NOTIFICATION_ROUTE_ADD, ipaddr, nexthop); call_route_callback(UIP_DS6_NOTIFICATION_ROUTE_ADD, ipaddr, nexthop);
#endif #endif
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
return r; return r;
} }
@ -283,13 +356,22 @@ uip_ds6_route_add(uip_ipaddr_t *ipaddr, uint8_t length,
void void
uip_ds6_route_rm(uip_ds6_route_t *route) uip_ds6_route_rm(uip_ds6_route_t *route)
{ {
if(route != NULL && route->route_list != NULL) { #if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
if(route != NULL && route->routes != NULL) {
if(list_head((list_t)route->route_list) == NULL) { PRINTF("uip_ds6_route_rm: removing route: ");
/* If this was the only route using this neighbor, remove the neibhor from the table */ PRINT6ADDR(&route->ipaddr);
nbr_table_remove(nbr_routes, route->route_list); PRINTF("\n");
list_remove(route->routes->route_list, route);
if(list_head(route->routes->route_list) == NULL) {
/* If this was the only route using this neighbor, remove the
neibhor from the table */
PRINTF("uip_ds6_route_rm: removing neighbor too\n");
nbr_table_remove(nbr_routes, route->routes->route_list);
} }
list_remove((list_t)route->route_list, route);
memb_free(&routememb, route); memb_free(&routememb, route);
num_routes--; num_routes--;
@ -300,13 +382,19 @@ uip_ds6_route_rm(uip_ds6_route_t *route)
call_route_callback(UIP_DS6_NOTIFICATION_ROUTE_RM, call_route_callback(UIP_DS6_NOTIFICATION_ROUTE_RM,
&route->ipaddr, uip_ds6_route_nexthop(route)); &route->ipaddr, uip_ds6_route_nexthop(route));
#endif #endif
#if (DEBUG & DEBUG_ANNOTATE) == DEBUG_ANNOTATE #if 0 //(DEBUG & DEBUG_ANNOTATE) == DEBUG_ANNOTATE
/* we need to check if this was the last route towards "nexthop" */ /* we need to check if this was the last route towards "nexthop" */
/* if so - remove that link (annotation) */ /* if so - remove that link (annotation) */
uip_ds6_route_t *r;
for(r = uip_ds6_route_head(); for(r = uip_ds6_route_head();
r != NULL; r != NULL;
r = uip_ds6_route_next(r)) { r = uip_ds6_route_next(r)) {
if(uip_ipaddr_cmp(uip_ds6_route_nexthop(r), uip_ds6_route_nexthop(route))) { uip_ipaddr_t *nextr, *nextroute;
nextr = uip_ds6_route_nexthop(r);
nextroute = uip_ds6_route_nexthop(route);
if(nextr != NULL &&
nextroute != NULL &&
uip_ipaddr_cmp(nextr, nextroute)) {
/* we found another link using the specific nexthop, so keep the #L */ /* we found another link using the specific nexthop, so keep the #L */
return; return;
} }
@ -314,30 +402,51 @@ uip_ds6_route_rm(uip_ds6_route_t *route)
ANNOTATE("#L %u 0\n", uip_ds6_route_nexthop(route)->u8[sizeof(uip_ipaddr_t) - 1]); ANNOTATE("#L %u 0\n", uip_ds6_route_nexthop(route)->u8[sizeof(uip_ipaddr_t) - 1]);
#endif #endif
} }
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
return; return;
} }
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
void static void
uip_ds6_route_rm_routelist(list_t nbr_route_list) rm_routelist(struct uip_ds6_route_neighbor_routes *routes)
{ {
if(nbr_route_list != NULL) { #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) {
uip_ds6_route_t *r; uip_ds6_route_t *r;
r = list_head((list_t)nbr_route_list); r = list_head(routes->route_list);
while(r != NULL) { while(r != NULL) {
uip_ds6_route_rm(r); uip_ds6_route_rm(r);
r = list_head((list_t)nbr_route_list); r = list_head(routes->route_list);
} }
nbr_table_remove(nbr_routes, nbr_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 void
uip_ds6_route_rm_by_nexthop(uip_ipaddr_t *nexthop) uip_ds6_route_rm_by_nexthop(uip_ipaddr_t *nexthop)
{ {
/* Get routing entry list of this neighbor */ /* Get routing entry list of this neighbor */
uip_lladdr_t *nexthop_lladdr = uip_ds6_nbr_lladdr_from_ipaddr(nexthop); uip_lladdr_t *nexthop_lladdr;
list_t nbr_route_list = nbr_table_get_from_lladdr(nbr_routes, (rimeaddr_t *)nexthop_lladdr); struct uip_ds6_route_neighbor_routes *routes;
uip_ds6_route_rm_routelist(nbr_route_list);
nexthop_lladdr = uip_ds6_nbr_lladdr_from_ipaddr(nexthop);
routes = nbr_table_get_from_lladdr(nbr_routes,
(rimeaddr_t *)nexthop_lladdr);
rm_routelist(routes);
} }
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
uip_ds6_defrt_t * uip_ds6_defrt_t *
@ -345,6 +454,11 @@ uip_ds6_defrt_add(uip_ipaddr_t *ipaddr, unsigned long interval)
{ {
uip_ds6_defrt_t *d; 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); d = uip_ds6_defrt_lookup(ipaddr);
if(d == NULL) { if(d == NULL) {
d = memb_alloc(&defaultroutermemb); d = memb_alloc(&defaultroutermemb);
@ -376,6 +490,10 @@ uip_ds6_defrt_add(uip_ipaddr_t *ipaddr, unsigned long interval)
call_route_callback(UIP_DS6_NOTIFICATION_DEFRT_ADD, ipaddr, ipaddr); call_route_callback(UIP_DS6_NOTIFICATION_DEFRT_ADD, ipaddr, ipaddr);
#endif #endif
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
return d; return d;
} }
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
@ -383,6 +501,11 @@ void
uip_ds6_defrt_rm(uip_ds6_defrt_t *defrt) uip_ds6_defrt_rm(uip_ds6_defrt_t *defrt)
{ {
uip_ds6_defrt_t *d; 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. */ /* Make sure that the defrt is in the list before we remove it. */
for(d = list_head(defaultrouterlist); for(d = list_head(defaultrouterlist);
d != NULL; d != NULL;
@ -399,6 +522,10 @@ uip_ds6_defrt_rm(uip_ds6_defrt_t *defrt)
return; return;
} }
} }
#if DEBUG != DEBUG_NONE
assert_nbr_routes_list_sane();
#endif /* DEBUG != DEBUG_NONE */
} }
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
uip_ds6_defrt_t * uip_ds6_defrt_t *

View file

@ -92,12 +92,21 @@ typedef struct rpl_route_entry {
} rpl_route_entry_t; } rpl_route_entry_t;
#endif /* UIP_DS6_ROUTE_STATE_TYPE */ #endif /* UIP_DS6_ROUTE_STATE_TYPE */
/** \brief The neighbor routes hold a list of routing table entries
that are attached to a specific neihbor. */
struct uip_ds6_route_neighbor_routes {
LIST_STRUCT(route_list);
};
/** \brief An entry in the routing table */ /** \brief An entry in the routing table */
typedef struct uip_ds6_route { typedef struct uip_ds6_route {
struct uip_ds6_route *next; struct uip_ds6_route *next;
list_t route_list; /* The list the routing entry belongs to. */ /* Each route entry belongs to a specific neighbor. That neighbor
holds a list of all routing entries that go through it. The
routes field point to the uip_ds6_route_neighbor_routes that
belong to the neighbor table entry that this routing table entry
uses. */
struct uip_ds6_route_neighbor_routes *routes;
uip_ipaddr_t ipaddr; uip_ipaddr_t ipaddr;
#ifdef UIP_DS6_ROUTE_STATE_TYPE #ifdef UIP_DS6_ROUTE_STATE_TYPE
UIP_DS6_ROUTE_STATE_TYPE state; UIP_DS6_ROUTE_STATE_TYPE state;