child-rekey: Add method to check for the redundant SA created in a collision

diff --git a/src/libcharon/sa/ikev2/tasks/child_rekey.c b/src/libcharon/sa/ikev2/tasks/child_rekey.c
index 3ce683440244fc072936ef6dafb16ebc49a9a446..5873a84af76e0fcb3aeef3f194369115f2acca4a 100644 (file)
--- a/src/libcharon/sa/ikev2/tasks/child_rekey.c
+++ b/src/libcharon/sa/ikev2/tasks/child_rekey.c
@@ -1,7 +1,8 @@
 /*
+ * Copyright (C) 2009-2016 Tobias Brunner
  * Copyright (C) 2005-2007 Martin Willi
  * Copyright (C) 2005 Jan Hutter
- * Hochschule fuer Technik Rapperswil
+ * HSR Hochschule fuer Technik Rapperswil
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
@@ -434,6 +435,18 @@ METHOD(task_t, get_type, task_type_t,
        return TASK_CHILD_REKEY;
 }
 
+METHOD(child_rekey_t, is_redundant, bool,
+       private_child_rekey_t *this, child_sa_t *child)
+{
+       if (this->collision &&
+               this->collision->get_type(this->collision) == TASK_CHILD_REKEY)
+       {
+               private_child_rekey_t *rekey = (private_child_rekey_t*)this->collision;
+               return child == rekey->child_create->get_child(rekey->child_create);
+       }
+       return FALSE;
+}
+
 METHOD(child_rekey_t, collide, void,
        private_child_rekey_t *this, task_t *other)
 {
@@ -452,19 +465,11 @@ METHOD(child_rekey_t, collide, void,
        else if (other->get_type(other) == TASK_CHILD_DELETE)
        {
                child_delete_t *del = (child_delete_t*)other;
-               if (this->collision &&
-                       this->collision->get_type(this->collision) == TASK_CHILD_REKEY)
+               if (is_redundant(this, del->get_child(del)))
                {
-                       private_child_rekey_t *rekey;
-
-                       rekey = (private_child_rekey_t*)this->collision;
-                       if (del->get_child(del) == rekey->child_create->get_child(rekey->child_create))
-                       {
-                               /* peer deletes redundant child created in collision */
-                               this->other_child_destroyed = TRUE;
-                               other->destroy(other);
-                               return;
-                       }
+                       this->other_child_destroyed = TRUE;
+                       other->destroy(other);
+                       return;
                }
                if (del->get_child(del) != this->child_sa)
                {
@@ -475,7 +480,7 @@ METHOD(child_rekey_t, collide, void,
        }
        else
        {
-               /* any other task is not critical for collisisions, ignore */
+               /* any other task is not critical for collisions, ignore */
                other->destroy(other);
                return;
        }
@@ -532,6 +537,7 @@ child_rekey_t *child_rekey_create(ike_sa_t *ike_sa, protocol_id_t protocol,
                                .migrate = _migrate,
                                .destroy = _destroy,
                        },
+                       .is_redundant = _is_redundant,
                        .collide = _collide,
                },
                .ike_sa = ike_sa,

diff --git a/src/libcharon/sa/ikev2/tasks/child_rekey.h b/src/libcharon/sa/ikev2/tasks/child_rekey.h
index cc041b953b5148ba94fee959c52d675c410b103a..0ad1a062d4d1286c66dde32beb8576e1e3528fa4 100644 (file)
--- a/src/libcharon/sa/ikev2/tasks/child_rekey.h
+++ b/src/libcharon/sa/ikev2/tasks/child_rekey.h
@@ -1,6 +1,7 @@
 /*
+ * Copyright (C) 2016 Tobias Brunner
  * Copyright (C) 2007 Martin Willi
- * Hochschule fuer Technik Rapperswil
+ * HSR Hochschule fuer Technik Rapperswil
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
@@ -39,13 +40,25 @@ struct child_rekey_t {
        task_t task;
 
        /**
-        * Register a rekeying task which collides with this one
+        * Check if the given SA is the redundant CHILD_SA created during a rekey
+        * collision.
+        *
+        * This is called if the other peer deletes the redundant SA before we were
+        * able to handle the CREATE_CHILD_SA response.
+        *
+        * @param child         CHILD_SA to check
+        * @return                      TRUE if the SA is the redundant CHILD_SA
+        */
+       bool (*is_redundant)(child_rekey_t *this, child_sa_t *child);
+
+       /**
+        * Register a rekeying/delete task which collides with this one
         *
         * If two peers initiate rekeying at the same time, the collision must
         * be handled gracefully. The task manager is aware of what exchanges
-        * are going on and notifies the outgoing task by passing the incoming.
+        * are going on and notifies the active task by passing the passive.
         *
-        * @param other         incoming task
+        * @param other         passive task (adopted)
         */
        void (*collide)(child_rekey_t* this, task_t *other);
 };