scope:

Introduction

This document specifies the algorithm identifiers and specifies parameters for the message digest algorithms SHA-224, SHA-256, SHA-384, and SHA-512 for use with the Cryptographic Message Syntax (CMS) [RFC5652]. The message digest algorithms are defined in [SHS] and reference code is provided in [RFC4634].

This document also specifies the algorithm identifiers and parameters for use of SHA-224, SHA-256, SHA-384, and SHA-512 with DSA [DSS], RSA (RSASSA-PKCS1-v1_5) [RFC3447], and ECDSA [DSS].

This document does not define new identifiers; they are taken from [RFC3874], [RFC4055], and [RFC5758]. Additionally, the parameters follow the conventions specified therein. Therefore, there is no Abstract Syntax Notation One (ASN.1) module included in this document.

Note that [RFC4231] specifies the conventions for the message authentication code (MAC) algorithms: Hashed MAC (HMAC) with SHA-224, HMAC with SHA-256, HMAC with SHA-384, and HMAC with SHA-512.

In the CMS, the various algorithm identifiers use the AlgorithmIdentifier syntax, which is included here for convenience:

AlgorithmIdentifier ::= SEQUENCE { algorithm OBJECT IDENTIFIER, parameters ANY DEFINED BY algorithm OPTIONAL }

This document also specifies the SMIMECapabilities attribute values [RFC5751] for each algorithm. The values provided are for the SMIMECapability field, which is included here for convenience:

SMIMECapability ::= SEQUENCE { capabilityID OBJECT IDENTIFIER, parameters ANY DEFINED BY capabilityID OPTIONAL }