Subject: Revisiting SHA-512/t HMAC_GENERAL
While following the example text from SHA1 and SHA512 in the previous version specification, my proposal for SHA-512/t variants included these 3 mechanisms: CKM_SHA512_224_HMAC_GENERAL CKM_SHA512_256_HMAC_GENERAL CKM_SHA512_T_HMAC_GENERAL The question raised in our group now is whether the *_GENERAL variants are needed at all, in the case of SHA-512/t. If one needs a shorter hash, selecting a smaller "t" should accomplish the same thing. Should these HMAC_GENERALs stay or be removed (via errata perhaps)? An ancillary question is about these existing mechanisms: CKM_SHA1_HMAC_GENERAL CKM_SHA224_HMAC_GENERAL CKM_SHA256_HMAC_GENERAL CKM_SHA384_HMAC_GENERAL CKM_SHA512_HMAC_GENERAL Does anyone have background on why were these were originally added to the specification? Are they still necessary to keep? It seems like I remember someone on-list brought up questions in this area, but it wasn't clear if he was talking about SHA-512/t itself, or the HMAC_GENERAL variants of all digest mechanisms. Any comments? Thanks, D.