SignedData

The signing building block of CMS, behind the pkcs7-signature part of S/MIME.

Definition

SignedData gathers the digest algorithms, the content (present or detached), the X.509 certificates, and a SET of SignerInfo carrying the signature and signed attributes (messageDigest, signingTime). In multipart/signed the content is detached; in smime-type=signed-data it is encapsulated (opaque signature).

Origin

Defined in section 5 of RFC 5652 (Cryptographic Message Syntax, IETF, 2009), descended from PKCS#7 and the basis of the CAdES formats.

Example in context

SignedData ::= SEQUENCE { version, digestAlgorithms, encapContentInfo, certificates, signerInfos }

Related terms

• EnvelopedData — the CMS encryption counterpart.
• XAdES CAdES PAdES — derived advanced signatures.