Previously, we failed without recovery if a private key did not support
a selected signature scheme (based on key strength and the other peer's
supported hash algorithms).
If this is disabled the schemes configured in `rightauth` are only
checked against signature schemes used in the certificate chain and
signature schemes used during IKEv2 are ignored.
Disabling this could be helpful if existing connections with peers that
don't support RFC 7427 use signature schemes in `rightauth` to verify
certificate chains.
This enables late connection switching based on the signature scheme used
for IKEv2 and allows to enforce stronger signature schemes.
This may break existing connections with peers that don't support RFC 7427
if signature schemes are currently used in `rightauth` for certificate chain
validation and if the configured schemes are stronger than the default used
for IKE (e.g. SHA-1 for RSA).
We use the new signature authentication instead for this. This is not
backward compatible but we only released one version with BLISS support,
and the key format will change anyway with the next release.
The previous code allowed an attacker to slip in an IKE_SA_INIT with
both SPIs and MID 1 set when an IKE_AUTH would be expected instead.
References #816.
This reverts 8f727d8007 ("Clean up IKE_SA state if IKE_SA_INIT request
does not have message ID 0") because it allowed to close any IKE_SA by
sending an IKE_SA_INIT with an unexpected MID and both SPIs set to those
of that SA.
The next commit will prevent SAs from getting created for IKE_SA_INIT messages
with invalid MID.
Fixes#816.
Under some conditions it can happen that the CREATE_CHILD_SA exchange for
rekeying the IKE_SA initiated by the peer is successful, but the delete message
does not follow. For example if processing takes just too long locally, the
peer might consider us dead, but we won't notice that.
As this leaves the old IKE_SA in IKE_REKEYING state, we currently avoid actively
initiating any tasks, such as rekeying or scheduled DPD. This leaves the IKE_SA
in a dead and unusable state. To avoid that situation, we schedule a timeout
to wait for the DELETE message to follow the CREATE_CHILD_SA, before we
actively start to delete the IKE_SA.
Alternatively we could start a liveness check on the SA after a timeout to see
if the peer still has that state and we can expect the delete to follow. But
it is unclear if all peers can handle such messages in this very special state,
so we currently don't go for that approach.
While we could calculate the timeout based on the local retransmission timeout,
the peer might use a different scheme, so a fixed timeout works as well.
Fixes#742.
As we now use the same reqid for multiple CHILD_SAs with the same selectors,
having marks based on the reqid makes not that much sense anymore. Instead we
use unique marks that use a custom identifier. This identifier is reused during
rekeying, keeping the marks constant for any rule relying on it (for example
installed by updown).
This also simplifies handling of reqid allocation, as we do not have to query
the marks that is not yet assigned for an unknown reqid.
For instance, if a DPD exchange is initiated by the gateway when a
mobile client is roaming and it then gets a new IP address and sends
an address update via MOBIKE, the DPD retransmits would still be sent
to the old address and the SA would eventually get closed.
This reverts commit 3293d14628.
The position of tasks in the queue does not actually determine the order
in which they are activated. Instead this is determined by the
statements in task_manager_v2_t.initiate().
This might not be the case if e.g. an address appeared but the old one
is still available but not actually usable. Without this the MOBIKE
task would eventually time out even though we might be able to switch
to a working address.
Tobias Brunner