If there are lots of SAs to be synced, the default might be too low
and messages and SAs get dropped. The new default is already 8 MiB,
which should work fine for lots of SAs. The code mirrors the one in
the kernel-netlink plugin (but with a guard around SO_RCVBUFFORCE, even
though this plugin is mostly used on Linux as well).
This requires a new protocol version as private extensions would enable
unrelated regular extensions, even when sending the private extension
as second attribute (which would work for conditions as they are
explicitly enabled/disabled).
As described in the previous commit, GCC 15 uses C23 by default and that
changes the meaning of such argument-less function declarations. So
whenever we assign such a function to a pointer that expects a function
with arguments it causes an incompatible pointer type warning. We
could define dedicated functions/callbacks whenever necessary, but this
seems like the simpler approach for now (especially since most uses of
these functions have already been cast).
Besides being clearer, this fixes issues with GCC 15. The latter uses
C23 by default, which changes the meaning of function declarations
without parameters such as
bool return false();
Instead of "this function takes an unknown number of arguments", this
now equals (void), that is, "this function takes no arguments". So we
run into incompatible pointer type warnings all over when using such
functions. They could be cast to (void*) but this seems the cleaner
solution for this use case.
The node that gets activated usually won't be able to complete the
IKE_SA mainly because the IKE keys are now derived delayed, so the key
material required to process a message often won't be available (only
later IKE_AUTH messages and retransmits of earlier messages that the
active node already received and synced the keys for may be decrypted).
A second issue affects IKE_SAs with multiple key exchanges. Because the
IntAuth value(s) are currently not synced, which are necessary to
verify/create the AUTH payloads, the IKE_AUTH exchange couldn't be
completed.
Synchronization for the additional transforms in the IKE and Child SA
proposals is added. Details of the IKE_SA synchronization are changed
to support IKE_INTERMEDIATE exchanges that cause multiple HA_IKE_ADD
messages and key derivations. The cache has been extended to handle
multiple such messages.
Co-authored-by: Thomas Egerer <thomas.egerer@secunet.com>
This is particularly important for higher number of segments, but even
with small numbers there is a significant difference. For instance,
with 4 segments the fourth segment had no IPs assigned with the old
code, no matter how large the pool, because none of the eight bits used
for the segment check hashed/mapped to it.
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.
With IKEv1 we transmit both public DH factors (used to derive the initial
IV) besides the shared secret. So these messages could get significantly
larger than 1024 bytes, depending on the DH group (modp2048 just about
fits into it). The new default of 2048 bytes should be fine up to modp4096
and for larger groups the buffer size may be increased (an error is
logged should this happen).
To handle Phase 2 exchanges on the other HA host we need to sync the last
block of the last Phase 1 message (or the last expected IV). If the
gateway is the initiator of a Main Mode SA the last message is an
inbound message. When handling such messages the expected IV is not
updated until it is successfully decrypted so we can't sync the IV
when processing the still encrypted (!plain) message. However, as responder,
i.e. if the last message is an outbound message, the reverse applies, that
is, we get the next IV after successfully encrypting the message, not
while handling the plain message.
Fixes#1267.
It is required for IKEv1 to determine the DH group of the CHILD SAs
during rekeying. It also fixes the status output for HA SAs, which so
far haven't shown the DH group on the passive side.
Fixes#1267.
Tobias Brunner