Retransmission jobs for old requests for which we already received a
response previously left the impression that messages were sent more
recently than was actually the case.
task_manager_t always defined INVALID_STATE as possible return value if
no retransmit was sent, this just was never actually returned.
I guess we could further differentiate between actual invalid states
(e.g. if we already received the response) and when we don't send a
retransmit for other reasons e.g. because the IKE_SA became stale.
This is useful on Android where the app might not be able to send
keep-alives if the device is asleep for a while. If the NAT mapping
has been deleted in the mean time, the NAT-D payloads allow detecting
this and connectivity can be restored by doing a MOBIKE update or
recreating the SA if the peer already deleted it because the client
wasn't reachable.
If we fail connecting to the host we got redirected to, we should restart
with the original host where we might get redirected to a different host.
We must not reset this when retrying due to INVALID_KE_PAYLOAD or COOKIE
notifies. Since we keep the initiator SPI in those cases, we use that
flag as indicator.
Since we don't store the original remote_host value, we can't restore
that. So there is a potential conflict with MIPv6.
Closesstrongswan/strongswan#171.
Due to the exponential backoff a high number of retransmits only
makes sense if retransmit_limit is set. However, even with that there
was a problem.
We first calculated the timeout for the next retransmit and only then
compared that to the configured limit. Depending on the configured
base and timeout the calculation overflowed the range of uint32_t after
a relatively low number of retransmits (with the default values after 23)
causing the timeout to first get lower (on a high level) before constantly
resulting in 0 (with the default settings after 60 retransmits).
Since that's obviously lower than any configured limit, all remaining
retransmits were then sent without any delay, causing a lot of concurrent
messages if the number of retransmits was high.
This change determines the maximum number of retransmits until an
overflow occurs based on the configuration and defaults to UINT32_MAX
if that value is exceeded. Note that since the timeout is in milliseconds
UINT32_MAX equals nearly 50 days.
The calculation in task_manager_total_retransmit_timeout() uses a double
variable and the result is in seconds so the maximum number would be higher
there (with the default settings 1205). However, we want its result to
be based on the actual IKE retransmission behavior.
Some peers apparently don't send the notify and still expect to
authenticate with EAP-only authentication. This option allows forcing
the configured use of EAP-only authentication in that scenario.
If such a task was active while reestablishing it will get queued on the
new IKE_SA. If the DH group is already set, the DH groups won't be
stripped from the proposals and a KE payload will be sent, which is invalid
during IKE_AUTH. We don't want to reset the group if the task is part of a
child-rekey task.
Charon refuses to make use of algorithms IDs from the private space
for unknown peer implementations [1]. If you chose to ignore and violate
that section of the RFC since you *know* your peers *must* support those
private IDs, there's no way to disable that behavior.
With this commit a strongswan.conf option is introduced which allows to
deliberately ignore parts of section 3.12 from the standard.
[1] http://tools.ietf.org/html/rfc7296#section-3.12
Signed-off-by: Thomas Egerer <[email protected]>
Previously, we simply used the lifetimes of the first
proposal/transform, which is not correct if the initiator uses different
lifetimes in its proposals/transforms.
If an IKE_SA is terminated while a task is active, the delete task is
simply queued (unless the deletion is forced). If the active task times
out before any optional timeout associated with the termination hits, the
IKE_SA previously was reestablished without considering the termination
request.
Fixes#3335.
RFC 7296, section 2.21.3:
If a peer parsing a request notices that it is badly formatted (after
it has passed the message authentication code checks and window
checks) and it returns an INVALID_SYNTAX notification, then this
error notification is considered fatal in both peers, meaning that
the IKE SA is deleted without needing an explicit Delete payload.
RFC 7296, section 2.21.3:
If a peer parsing a request notices that it is badly formatted (after
it has passed the message authentication code checks and window
checks) and it returns an INVALID_SYNTAX notification, then this
error notification is considered fatal in both peers, meaning that
the IKE SA is deleted without needing an explicit Delete payload.
This avoids having to register certificates with authority/ca backends
beforehand, which is tricky for intermediate CA certificates loaded
themselves via authority/ca sections. On the other hand, the form of
these URLs can't be determined by config backends anymore (not an issue
for the two current implementations, no idea if custom implementations
ever made use of that possibility). If that became necessary, we could
perhaps pass the certificate to the CDP enumerator or add a new method
to the credential_set_t interface.
This avoids having to call strip_dh() in child_cfg_t::get_proposals().
It also inverts the ALLOW_PRIVATE flag (i.e. makes it SKIP_PRIVATE) so
nothing has to be supplied to clone complete proposals.
During proposal selection with ike/child_cfgs a couple of boolean
variables can be set (e.g. private, prefer_self, strip_dh). To simplify
the addition of new parameters, these functions now use a set of flags
instead of indiviual boolean values.
Signed-off-by: Thomas Egerer <[email protected]>
There seem to be servers around that, upon receiving a delete from the
client, instead of responding with an empty INFORMATIONAL, send a delete
themselves.
If CHILD_SAs are created while waiting for the third QM message we'd not
notice the redundancy and updown events would be triggered unevenly.
This is consistent with the behavior on the initiator, which already does
this check right before installation. Moving the existing check is not
possible due to the narrow hook and moving the installation changes which
peer installs the SAs first and could have other side-effects (e.g. in
error or conflict cases). Still, this might result in CHILD_SA state
discrepancies between the two peers.
Fixes#3060.
Previously, the initiator would install the SA in transport mode if the
peer sent back the USE_TRANSPORT_MODE notify, even if that was not
requested originally.
Might be useful for users of other daemons too. Note that compared to the
previous implementation in charon-tkm, the mask/label are applied in
network order.
Closesstrongswan/strongswan#134.
Previously, attributes in an incorrectly sent CFG_REPLY would still be passed
to attribute handlers. This does not prevent handlers from receiving
unrequested attributes if they requested at least one other.
There was a race condition between install() and uninstall()
where one thread was in the process of installing a trap
entry, and had destroyed the child_sa, while the other
thread was uninstalling the same trap entry and ended up
trying to destroy the already destroyed child_sa, resulting
in a segmentation fault in the destroy_entry() function.
The uninstall() function needs to wait until all the threads
are done with the installing before proceeding to uninstall
a trap entry.
Closesstrongswan/strongswan#131.
A temporary DROP policy is added to avoid traffic leak
while the SA is being updated. It is added with
manual_prio set but when the temporary policy is removed
it is removed with manual_prio parameter set to 0.
The call to del_policies_outbound does not match the original
policy and we end up with an ever increasing refcount.
If we try to manually remove the policy, it is not removed
due to the positive refcount. Then new SA requests fail with
"unable to install policy out for reqid 1618,
the same policy for reqid 1528 exists"
Fixes: 35ef1b032d ("child-sa: Install drop policies while updating IPsec SAs and policies")
Closesstrongswan/strongswan#129.
Tobias Brunner