Merge pull request #8083 from miri64/gnrc_ipv6_nib/api/prime-dr

gnrc_ipv6_nib: make user added default route the primary one
RIOT-OS · Nov 19, 2017 · 21a5561 · 21a5561
2 parents ba77fd5 + 2f7b55b
commit 21a5561
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Showing 5 changed files with 53 additions and 5 deletions.
diff --git a/sys/include/net/gnrc/ipv6/nib/ft.h b/sys/include/net/gnrc/ipv6/nib/ft.h
@@ -62,6 +62,9 @@ int gnrc_ipv6_nib_ft_get(const ipv6_addr_t *dst, gnrc_pktsnip_t *pkt,
 /**
  * @brief   Adds a new route to the forwarding table
  *
+ * If @p dst is the default route, the route will be configured to be the
+ * default route.
+ *
  * @param[in] dst       The destination to the route. May be NULL or `::` for
  *                      default route.
  * @param[in] dst_len   The prefix length of @p dst in bits. May be 0 for
@@ -83,6 +86,9 @@ int gnrc_ipv6_nib_ft_add(const ipv6_addr_t *dst, unsigned dst_len,
 /**
  * @brief   Deletes a route from forwarding table.
  *
+ * If @p dst is the default route, the function assures, that the current
+ * primary default route is removed first.
+ *
  * @param[in] dst       The destination of the route. May be NULL or `::` for
  *                      default route.
  * @param[in] dst_len   The prefix length of @p dst in bits. May be 0 for

diff --git a/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.c b/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.c
@@ -31,7 +31,7 @@
 #include "debug.h"
 
 /* pointers for default router selection */
-static _nib_dr_entry_t *_prime_def_router = NULL;
+_nib_dr_entry_t *_prime_def_router = NULL;
 static clist_node_t _next_removable = { NULL };
 
 static _nib_onl_entry_t _nodes[GNRC_IPV6_NIB_NUMOF];

diff --git a/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.h b/sys/net/gnrc/network_layer/ipv6/nib/_nib-internal.h
@@ -250,6 +250,16 @@ extern mutex_t _nib_mutex;
  */
 extern evtimer_msg_t _nib_evtimer;
 
+/**
+ * @brief   Primary default router.
+ *
+ * This value is returned by @ref @_nib_drl_get_dr() when it is not NULL and it
+ * is reachable. Otherwise it is selected with the [default router selection
+ * algoritm](https://tools.ietf.org/html/rfc4861#section-6.3.6) by that function.
+ * Exposed to be settable by @ref net_gnrc_ipv6_nib_ft.
+ */
+extern _nib_dr_entry_t *_prime_def_router;
+
 /**
  * @brief   Initializes NIB internally
  */

diff --git a/sys/net/gnrc/network_layer/ipv6/nib/nib_ft.c b/sys/net/gnrc/network_layer/ipv6/nib/nib_ft.c
@@ -51,9 +51,12 @@ int gnrc_ipv6_nib_ft_add(const ipv6_addr_t *dst, unsigned dst_len,
         if (ptr == NULL) {
             res = -ENOMEM;
         }
-        else if (ltime > 0) {
-            _evtimer_add(ptr, GNRC_IPV6_NIB_RTR_TIMEOUT,
-                         &ptr->rtr_timeout, ltime * MS_PER_SEC);
+        else {
+            _prime_def_router = ptr;
+            if (ltime > 0) {
+                _evtimer_add(ptr, GNRC_IPV6_NIB_RTR_TIMEOUT,
+                             &ptr->rtr_timeout, ltime * MS_PER_SEC);
+            }
         }
     }
 #if GNRC_IPV6_NIB_CONF_ROUTER

diff --git a/tests/unittests/tests-gnrc_ipv6_nib/tests-gnrc_ipv6_nib-ft.c b/tests/unittests/tests-gnrc_ipv6_nib/tests-gnrc_ipv6_nib-ft.c
@@ -568,6 +568,28 @@ static void test_nib_ft_add__success(void)
     TEST_ASSERT(!gnrc_ipv6_nib_ft_iter(NULL, 0, &iter_state, &fte));
 }
 
+/*
+ * Creates a default route
+ * Expected result: a new entry should exist and contain the given prefix,
+ * interface, and lifetimes and it should be the primary default route
+ */
+static void test_nib_ft_add__success_dr(void)
+{
+    gnrc_ipv6_nib_ft_t fte;
+    void *iter_state = NULL;
+    static const ipv6_addr_t next_hop = { .u64 = { { .u8 = LINK_LOCAL_PREFIX },
+                                                 { .u64 = TEST_UINT64 } } };
+
+    TEST_ASSERT_EQUAL_INT(0, gnrc_ipv6_nib_ft_add(NULL, 0, &next_hop, IFACE, 0));
+    TEST_ASSERT(gnrc_ipv6_nib_ft_iter(NULL, 0, &iter_state, &fte));
+    TEST_ASSERT(ipv6_addr_is_unspecified(&fte.dst));
+    TEST_ASSERT_EQUAL_INT(0, fte.dst_len);
+    TEST_ASSERT(ipv6_addr_equal(&fte.next_hop, &next_hop));
+    TEST_ASSERT_EQUAL_INT(IFACE, fte.iface);
+    TEST_ASSERT_EQUAL_INT(1, fte.primary);
+    TEST_ASSERT(!gnrc_ipv6_nib_ft_iter(NULL, 0, &iter_state, &fte));
+}
+
 /*
  * Creates MAX_NUMOF routes with different destinations of to the different
  * next hops and interfaces and then tries to delete one with yet another
@@ -639,13 +661,19 @@ static void test_nib_ft_iter__empty_def_route_at_beginning(void)
     next_hop.u16[0].u16++;
     TEST_ASSERT_EQUAL_INT(0, gnrc_ipv6_nib_ft_add(NULL, 0,
                                                   &next_hop, IFACE, 0));
+    /* make first added route the primary default route again */
+    next_hop.u16[0].u16 -= 2;
+    TEST_ASSERT_EQUAL_INT(0, gnrc_ipv6_nib_ft_add(NULL, 0,
+                                                  &next_hop, IFACE, 0));
+    /* remove primary default route */
     gnrc_ipv6_nib_ft_del(NULL, 0);
-    next_hop.u16[0].u16--;
+    next_hop.u16[0].u16++;
     while (gnrc_ipv6_nib_ft_iter(NULL, 0, &iter_state, &fte)) {
         TEST_ASSERT(ipv6_addr_is_unspecified(&fte.dst));
         TEST_ASSERT(ipv6_addr_equal(&fte.next_hop, &next_hop));
         TEST_ASSERT_EQUAL_INT(0, fte.dst_len);
         TEST_ASSERT_EQUAL_INT(IFACE, fte.iface);
+        TEST_ASSERT(!fte.primary);
         count++;
         next_hop.u16[0].u16++;
     }
@@ -717,6 +745,7 @@ Test *tests_gnrc_ipv6_nib_ft_tests(void)
         new_TestFixture(test_nib_ft_add__success_duplicate),
         new_TestFixture(test_nib_ft_add__success_overwrite_unspecified),
         new_TestFixture(test_nib_ft_add__success),
+        new_TestFixture(test_nib_ft_add__success_dr),
         new_TestFixture(test_nib_ft_del__unknown),
         new_TestFixture(test_nib_ft_del__success),
         /* most of gnrc_ipv6_nib_ft_iter() is tested during all the tests above */