ike-rekey: Properly handle situation if the peer did not notice the rekey collision

We conclude the rekeying before deleting the IKE_SA.  Waiting for the
potential TEMPORARY_FAILURE notify is no good because if that response
does not reach us the peer will not retransmit it upon our retransmits
of the rekey request if it already deleted the IKE_SA after receiving
our response to the delete.

diff --git a/src/libcharon/sa/ikev2/tasks/ike_rekey.c b/src/libcharon/sa/ikev2/tasks/ike_rekey.c
index 2d0b8f2940fe5fd9312e2c6f15af0bc2b57dc36f..e99536e2d317fb26ce5a4b80294217da27038617 100644 (file)
--- a/src/libcharon/sa/ikev2/tasks/ike_rekey.c
+++ b/src/libcharon/sa/ikev2/tasks/ike_rekey.c
@@ -392,6 +392,17 @@ METHOD(ike_rekey_t, collide, void,
 {
        DBG1(DBG_IKE, "detected %N collision with %N", task_type_names,
                 TASK_IKE_REKEY, task_type_names, other->get_type(other));
+       if (other->get_type(other) == TASK_IKE_DELETE)
+       {
+               if (this->collision &&
+                       this->collision->get_type(this->collision) == TASK_IKE_REKEY)
+               {
+                       DBG1(DBG_IKE, "peer did not notice IKE_SA rekey collision");
+                       other->destroy(other);
+                       establish_new((private_ike_rekey_t*)this->collision);
+                       return;
+               }
+       }
        DESTROY_IF(this->collision);
        this->collision = other;
 }