Hi Ilari, The problem is that we couldn't find out what those use cases are that would benefit from using this structure. Even without this structure, HPKE already utilizes all the relevant information in is key derivation.
Ciao Hannes -----Original Message----- From: COSE <[email protected]> On Behalf Of Ilari Liusvaara Sent: Friday, July 8, 2022 4:57 PM To: cose <[email protected]> Subject: Re: [COSE] COSE-HPKE COSE_KDF_Context On Fri, Jul 08, 2022 at 09:05:44AM +0000, Hannes Tschofenig wrote: > > Hi Ilari, > > At the IETF#113 in Vienna (see slide 9 in > https://datatracker.ietf.org/meeting/113/materials/slides-113-cose-dra > ft-ietf-cose-hpke-00) I suggested to remove Section 3.4 from the draft > for the following > reasons: > > * HPKE itself defines ways to add extra info into the key > derivation function, and > * HPKE incorporates various fields in the key derivation process > already. > > If you are OK with it, I would delete Section 3.4 from the cose-hpke draft. The info structure is exactly what is added as extra info to the HPKE key derivation function. And it is not quite redundant: In some cases, one might want to pull PartyUInfo from enveloping cose_signature0 or cose_mac0. And some applications might do something (non-interoprable) with SuppPubInfo.other/SuppPrivInfo. -Ilari _______________________________________________ COSE mailing list [email protected] https://www.ietf.org/mailman/listinfo/cose IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. _______________________________________________ COSE mailing list [email protected] https://www.ietf.org/mailman/listinfo/cose
