On Tue, 25 Aug 2026, Andrew Cagney wrote:
3. Authentication Payload
This document specifies a new "Digital Signature" authentication
method. This method can be used with any type of signature. As the
authentication methods are not negotiated in IKEv2, the peer is only
allowed to use this authentication method if the Notify payload of
type SIGNATURE_HASH_ALGORITHMS has been sent and received by each
peer.
i.e., digital signature can only be used when both ends have sent a
signature_hash_algorithm notification.
However, consider asymmetric authentication.
You have to read it as a SUPPPORTED style notify. Not as in a "allowed
for this connection" notify.
The supported hash algorithms that can be used for the signature
algorithms are indicated with a Notify payload of type
SIGNATURE_HASH_ALGORITHMS sent inside the IKE_SA_INIT exchange.
Since PSK would like its peer, DIGSIG, to use the digital signature in
the AUTH payload it sends a list of allowed hash algorithms.
Not "allowed" but "supported".
However, I wonder if instead, DIGSIG should be allowed to skip sending
a SIGNATURE_HASH_ALGORITHM notification to PSK.
You can't because in IKE_SA_INIT you don't know yet which configuration
might be picked and you might have PSK and DigSig peers defined.
Paul
_______________________________________________
IPsec mailing list -- [email protected]
To unsubscribe send an email to [email protected]
