Some tasks might get removed immediately once the IKE_SA_INIT response has
been handled even if there were notifies that require a restart of the
IKE_SA (e.g. COOKIE or INVALID_KE_PAYLOAD). Such a task is ike_vendor,
which caused vendor IDs not to get sent in a retry. This change ensures
all required tasks are queued after the reset, which some callers did
already anyway.
These seem to indicate the major and minor version of the protocol, like
e.g. for the DPD vendor ID. Some implementations seem to send versions
other than 1.0 so we just ignore these for now when checking for known
vendor IDs.
Fixes#2088.
By aborting the active task we don't have to wait for potential
retransmits if the other peer does not respond to the current task.
Since IKEv1 has no sequential message IDs and INFORMATIONALs are no real
exchanges this should not be a problem.
Fixes#1537
References #429, #1410Closesstrongswan/strongswan#48
Depending on the lifetimes a CHILD_SA we rekeyed as responder might
expire shortly afterwards. We don't want to rekey it again.
When retrying due to an INVALID_KE_PAYLOAD notify the expected state
is CHILD_REKEYING if it is anything else (e.g. due to a collision) we
ignore it.
We also abort the exchange properly if we don't find the CHILD_SA, no
need for an empty INFORMATIONAL exchange anymore.
If a passive rekeying fails due to an INVALID_KE_PAYLOAD we don't want
to consider this task later when resolving collisions. This previously
might have caused the wrong SA to get deleted/installed based on the nonces
in the unsuccessful exchange.
Such a task is not initiated unless a certain time has passed. This
allows delaying certain tasks but avoids problems if we'd do this
via a scheduled job (e.g. if the IKE_SA is rekeyed in the meantime).
If the IKE_SA is rekeyed the delay of such tasks is reset when the
tasks are adopted i.e. they get executed immediately on the new IKE_SA.
This hasn't been implemented for IKEv1 yet.
If the peer does not detect the rekey collision and deletes the old
IKE_SA and then receives the colliding rekey request it will respond with
TEMPORARY_FAILURE. That notify may arrive before the DELETE does, in
which case we may just conclude the rekeying initiated by the peer.
Also, since the IKE_SA is destroyed in any case when we receive a delete
there is no point in storing the delete task in collide() as process_i()
in the ike-rekey task will never be called.
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.
This makes handling such IKE_SAs more specifically compared to keeping them
in state IKE_CONNECTING or IKE_ESTABLISHED (which we did when we lost a
collision - even triggering the ike_updown event), or using IKE_REKEYING for
them, which would also be ambiguous.
For instance, we can now reject anything but DELETES for such SAs.
Tobias Brunner