ikev2: Delay online revocation checks during make-before-break reauthentication

We do these checks after the SA is fully established.

When establishing an SA the responder is always able to install the
CHILD_SA created with the IKE_SA before the initiator can do so.
During make-before-break reauthentication this could cause traffic sent
by the responder to get dropped if the installation of the SA on the
initiator is delayed e.g. by OCSP/CRL checks.

In particular, if the OCSP/CRL URIs are reachable via IPsec tunnel (e.g.
with rightsubnet=0.0.0.0/0) the initiator is unable to reach them during
make-before-break reauthentication as it wouldn't be able to decrypt the
response that the responder sends using the new CHILD_SA.

By delaying the revocation checks until the make-before-break
reauthentication is completed we avoid the problems described above.
Since this only affects reauthentication, not the original IKE_SA, and the
delay until the checks are performed is usually not that long this
doesn't impose much of a reduction in the overall security.

diff --git a/src/libcharon/sa/ikev2/task_manager_v2.c b/src/libcharon/sa/ikev2/task_manager_v2.c
index c573c23c85a7c609085edd74d2e594a37d2cb619..c2f972ab16327f7f7a9c0b3ac208bfcf0b2987fb 100644 (file)
--- a/src/libcharon/sa/ikev2/task_manager_v2.c
+++ b/src/libcharon/sa/ikev2/task_manager_v2.c
@@ -35,6 +35,7 @@
 #include <sa/ikev2/tasks/ike_config.h>
 #include <sa/ikev2/tasks/ike_dpd.h>
 #include <sa/ikev2/tasks/ike_vendor.h>
+#include <sa/ikev2/tasks/ike_verify_peer_cert.h>
 #include <sa/ikev2/tasks/child_create.h>
 #include <sa/ikev2/tasks/child_rekey.h>
 #include <sa/ikev2/tasks/child_delete.h>
@@ -1655,8 +1656,12 @@ static void trigger_mbb_reauth(private_task_manager_t *this)
        }
        enumerator->destroy(enumerator);
 
+       /* suspend online revocation checking until the SA is established */
+       new->set_condition(new, COND_ONLINE_VALIDATION_SUSPENDED, TRUE);
+
        if (new->initiate(new, NULL, 0, NULL, NULL) != DESTROY_ME)
        {
+               new->queue_task(new, (task_t*)ike_verify_peer_cert_create(new));
                new->queue_task(new, (task_t*)ike_reauth_complete_create(new,
                                                                                this->ike_sa->get_id(this->ike_sa)));
                charon->ike_sa_manager->checkin(charon->ike_sa_manager, new);