Since these are installed overlapping (like during a rekeying) we have to use
the same (unique) marks (and possibly reqid) that were used previously,
otherwise, the policy installation will fail.
Fixes#2610.
The previous code was obviously incorrect and caused strange side effects
depending on the compiler and its optimization flags (infinite looping seen
with GCC 4.8.4, segfault when destroying the private key in build() seen
with clang 4.0.0 on FreeBSD).
Fixes#2579.
If we receive an INVALID_KE_PAYLOAD notify we should not just retry
with the requested DH group without checking first if we actually propose
the group (or any at all).
Reqids for the same traffic selectors are now stable so we don't have to
pass reqids of previously installed CHILD_SAs. Likewise, we don't need
to know the reqid of the newly installed trap policy as we now uninstall
by name.
This is really only needed for other exchanges like DPDs not when we
just updated the addresses. The NAT-D payloads are only used here to
detect whether UDP encapsulation has to be enabled/disabled.
The counter does not tell us what task is actually queued, so we might
ignore the response to an update (with NAT-D payloads) if only an address
update is queued.
Instead of destroying the new task and keeping the existing one we
update any already queued task, so we don't loose any work (e.g. if a
DPD task is active and address update is queued and we'd actually like
to queue a roam task).
This is currently not an issue for CHILD_SA rekeying tests as these only
check rekeyings of the CHILD_SA created with the IKE_SA, i.e. there is
no previous DH group to reuse.
For the CHILD_SA created with the IKE_SA the group won't be set in the
proposal, so we will use the first one configure just as if the SA was
created new with a CREATE_CHILD_SA exchange. I guess we could
theoretically try to use the DH group negotiated for IKE but then this
would get a lot more complicated as we'd have to check if that group is
actually contained in any of the CHILD_SA's configured proposals.
This way we get proper error handling if the DH group the peer requested
is not actually supported for some reason (otherwise we'd just retry to
initiate with the configured group and get back another notify).
We do something similar in reestablish() for break-before-make reauth.
If we don't abort we'd be sending an IKE_AUTH without any TS payloads.
References #2430.
This causes problems e.g. on Android where we handle the alert (and
reestablish the IKE_SA) even though it usually is no problem if the
peer retries with the requested group. We don't consider it as a
failure on the initiator either.
In case we send retransmits for an IKE_SA_INIT where we propose a DH
group the responder will reject we might later receive delayed responses
that either contain INVALID_KE_PAYLOAD notifies with the group we already
use or, if we retransmitted an IKE_SA_INIT with the requested group but
then had to restart again, a KE payload with a group different from the
one we proposed. So far we didn't change the initiator SPI when
restarting the connection, i.e. these delayed responses were processed
and might have caused fatal errors due to a failed DH negotiation or
because of the internal retry counter in the ike-init task. Changing
the initiator SPI avoids that as we won't process the delayed responses
anymore that caused this confusion.
This splits the SA installation also on the initiator, so we can avoid
installing the outbound SA if we lost a rekey collision, which might
have caused traffic loss depending on the timing of the DELETEs that are
sent in both directions.
This way we get the log message in stroke and swanctl as last message
when establishing a connection. It's already like this for the IKE_SA
where IKE_ESTABLISHED is set after the corresponding log message.
Fixes#2364.
After deleting a rekeyed CHILD_SA we uninstall the outbound SA but don't
destroy the CHILD_SA (and the inbound SA) immediately. We delay it
a few seconds or until the SA expires to allow delayed packets to get
processed. The CHILD_SA remains in state CHILD_DELETING until it finally
gets destroyed.
Tobias Brunner