While combining the actions could cause duplicates (while the SA is
initiated, traffic might trigger the trap and the initiation of another
CHILD_SA), the previous commit should avoid most duplicates. If reuse_ikesa
is disabled, duplicates can't be prevented, though.
These are set via methods, which are not called again after migration
(e.g. when retrying due to INVALID_KE or when moving queued tasks), so we
don't want to clear these values.
Currently the length of vendor ID Cisco VPN Concentrator is 16
bytes but the string has only 13+1 bytes. The actual vendor
ID has 16 bytes with a prefix length of 14 bytes and two version
bytes.
Fixes: 6c49ddfbca ("ike: Add additional Vendor IDs for third-party implementations")
Before commit 6c49ddfbca ("ike: Add additional Vendor IDs for
third-party implementations") the prefix length of vendor ID
Cisco Unity was hardcoded to 14. Since we need to know the actual
length of this VID to send it, the length can't be overloaded
with a prefix length. Revert part of commit 6c49ddfbca to
fix this problem.
Fixes: 6c49ddfbca ("ike: Add additional Vendor IDs for third-party implementations")
Before commit 6c49ddfbca ("ike: Add additional Vendor IDs for
third-party implementations") the prefix length of vendor ID
MS NT5 ISAKMPOAKLEY was hardcoded to 16. Change the prefix length
accordingly.
Fixes: 6c49ddfbca ("ike: Add additional Vendor IDs for third-party implementations")
This now includes all key material derived for IKE_SAs in the order
defined in the RFC:
{SK_d | SK_ai | SK_ar | SK_ei | SK_er | SK_pi | SK_pr}
= prf+ (SKEYSEED, Ni | Nr | SPIi | SPIr)
Signed-off-by: Thomas Egerer <thomas.egerer@secunet.com>
For some that are followed by unknown data (e.g. detailed version
information) we only do a prefix match.
Co-authored-by: Tobias Brunner <tobias@strongswan.org>
Closesstrongswan/strongswan#393.
We don't actually check that SA out (i.e. it's not registered with the
manager). That was originally different but had to be changed with
86993d6b90 to avoid that SAs created for rekeying don't block other
threads on the manager.
This allows more fine grained control over what's updated and does not
require multiple calls of the method. Plus we'll be able to use it in
the ike-mobike task.
We usually have a local IP already via ike_sa_t::resolve_hosts() before
build_i() is called but if that's not the case, it's more likely we have
one after we processed the first response (it might also have changed).
There is a potential chance we still don't have one if the socket API
doesn't provide us with the destination address of received messages,
but that seems not very likely nowadays.
We need the PSK/identity already when deriving the keys in process_i().
Fixes: 1665a4e050 ("ikev1: Use actual local identity as initiator or aggressive mode responder")
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.
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.
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 <thomas.egerer@secunet.com>
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.
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 <thomas.egerer@secunet.com>
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.
If a lot of QUICK_MODE tasks are queued and the other side
sends a DPD request, there is a good chance for timeouts.
Observed this in cases where other side is quite slow in responding
QUICK_MODE requests (e.g. Cisco ASA v8.x) and about 100 CHILD_SAs
are to be spawned.
Closesstrongswan/strongswan#115.
The task manager for IKEv1 issues a retransmit send alert in the
retransmit_packet() function. The corresponding retransmit cleared alert
however is only issued for exchanges we initiated after processing the
response in process_response().
For quick mode exchanges we may retransmit the second packet if the peer
(the initiator) does not send the third message in a timely manner. In
this case the retransmit send alert may never be cleared.
With this patch the retransmit cleared alert is issued for packets that
were retransmitted also when we are the responding party when we receive
the outstanding response.
Signed-off-by: Thomas Egerer <thomas.egerer@secunet.com>
We don't retransmit DPD requests like we do requests for proper exchanges,
so increasing the number with each sent DPD could result in the peer's state
getting out of sync if DPDs are lost. Because according to RFC 3706, DPDs
with an unexpected sequence number SHOULD be rejected (it does mention the
possibility of maintaining a window of acceptable numbers, but we currently
don't implement that). We partially ignore such messages (i.e. we don't
update the expected sequence number and the inbound message stats, so we
might send a DPD when none is required). However, we always send a response,
so a peer won't really notice this (it also ensures a reply for "retransmits"
caused by this change, i.e. multiple DPDs with the same number - hopefully,
other implementations behave similarly when receiving such messages).
Fixes#2714.
This is mainly for HA where a passive SA was already created when the
IKE keys were derived. If e.g. an authentication error occurs later that
SA wouldn't get cleaned up.
Tobias Brunner