Added support for IKEv2 make-before-break reauthentication. By using a global CHILD_SA reqid allocation mechanism, charon supports overlapping CHILD_SAs. This allows the use of make-before-break instead of the previously supported break-before-make reauthentication, avoiding connectivity gaps during that procedure. As the new mechanism may fail with peers not supporting it (such as any previous strongSwan release) it must be explicitly enabled using the charon.make_before_breakstrongswan.conf option.
Support for Signature Authentication in IKEv2 (RFC 7427) has been added. This allows the use of stronger hash algorithms for public key authentication. By default, signature schemes are chosen based on the strength of the signature key, but specific hash algorithms may be configured in leftauth.
Key types and hash algorithms specified in rightauth are now also checked against IKEv2 signature schemes. If such constraints are used for certificate chain validation in existing configurations, in particular with peers that don't support RFC 7427, it may be necessary to disable this feature with the charon.signature_authentication_constraints setting, because the signature scheme used in classic IKEv2 public key authentication may not be strong enough.
The new connmark plugin allows a host to bind conntrack flows to a specific CHILD_SA by applying and restoring the SA mark to conntrack entries. This allows a peer to handle multiple transport mode connections coming over the same NAT device for client-initiated flows (a common use case is to protect L2TP/IPsec). See ikev2/host2host-transport-connmark for an example.
The forecast plugin can forward broadcast and multicast messages between connected clients and a LAN. For CHILD_SA using unique marks, it sets up the required Netfilter rules and uses a multicast/broadcast listener that forwards such messages to all connected clients. This plugin is designed for Windows 7 IKEv2 clients, which announce their services over the tunnel if the negotiated IPsec policy allows it. See ikev2/forecast for an example.
For the vici plugin a Python Egg has been added to allow Python applications to control or monitor the IKE daemon using the VICI interface, similar to the existing ruby gem. The Python library has been contributed by Björn Schuberg.
EAP server methods now can fulfill public key constraints, such as rightcert or rightca. Additionally, public key and signature constraints can be specified for EAP methods in the rightauth keyword. Currently the EAP-TLS and EAP-TTLS methods provide verification details to constraints checking.
Upgrade of the BLISS post-quantum signature algorithm to the improved BLISS-B variant. Can be used in conjunction with the SHA256, SHA384 and SHA512 hash algorithms with SHA512 being the default.
The IF-IMV 1.4 interface now makes the IP address of the TNC access requestor as seen by the TNC server available to all IMVs. This information can be forwarded to policy enforcement points (e.g. firewalls or routers).
The new mutual tnccs-20 plugin parameter activates mutual TNC measurements in PB-TNC half-duplex mode between two endpoints over either a PT-EAP or PT-TLS transport medium.
SPIs in IKEv1 DELETE payloads are now compared to those of the current IKE SA. This is required for interoperability with OpenBSD's isakmpd, which always uses the latest IKE SA to delete other expired SAs.
The files plugin provides a simple fetcher for file:// URIs (1735d80f38).
Fixed CRL verification for PKIs that don't use SHA-1 hashes of the public key as subjectKeyIdentifier or authorityKeyIdentifier (6133770db4).
Route priorities are now considered when doing manual route lookups (6b57790270).
Policies are now removed from the kernel before IPsec SAs, to avoid acquires for untrapped policies (46188b0eb0).