The Cryptographic Message Syntax (CMS) is the
IETF
The Internet Engineering Task Force (IETF) is a standards organization for the Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster or requirements and a ...
's standard for
cryptographically
Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adv ...
protected messages. It can be used by cryptographic schemes and protocols to
digitally sign,
digest,
authenticate
Authentication (from ''authentikos'', "real, genuine", from αὐθέντης ''authentes'', "author") is the act of proving an assertion, such as the identity of a computer system user. In contrast with identification, the act of indicatin ...
or
encrypt
In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Ideally, only authorized parties can deci ...
any form of digital data.
CMS is based on the syntax of
PKCS #7, which in turn is based on the
Privacy-Enhanced Mail
Privacy-Enhanced Mail (PEM) is a de facto file format for storing and sending cryptographic keys, certificates, and other data, based on a set of 1993 IETF standards defining "privacy-enhanced mail." While the original standards were never broadl ...
standard. The newest version of CMS () is specified in (but see also for updated ASN.1 modules conforming to ASN.1 2002).
The architecture of CMS is built around
certificate-based key management, such as the profile defined by the
PKIX
In cryptography, X.509 is an International Telecommunication Union (ITU) standard defining the format of public key certificates. X.509 certificates are used in many Internet protocols, including TLS/SSL, which is the basis for HTTPS, the secu ...
working group
A working group, or working party, is a group of experts working together to achieve specified goals. The groups are domain-specific and focus on discussion or activity around a specific subject area. The term can sometimes refer to an interdis ...
.
CMS is used as the key cryptographic component of many other cryptographic standards, such as
S/MIME S/MIME (Secure/Multipurpose Internet Mail Extensions) is a standard for public key encryption and signing of MIME data. S/MIME is on an IETF standards track and defined in a number of documents, most importantly . It was originally developed by R ...
,
PKCS #12 and the
digital timestamping protocol.
OpenSSL is
open source software that can encrypt, decrypt, sign and verify, compress and uncompress CMS documents.
See also
*
CAdES - CMS Advanced Electronic Signatures
*
S/MIME S/MIME (Secure/Multipurpose Internet Mail Extensions) is a standard for public key encryption and signing of MIME data. S/MIME is on an IETF standards track and defined in a number of documents, most importantly . It was originally developed by R ...
*
PKCS #7
External links
* (Update to the Cryptographic Message Syntax (CMS) for Algorithm Identifier Protection)
* (Cryptographic Message Syntax (CMS), in use)
* (Cryptographic Message Syntax (CMS), obsolete)
* (Cryptographic Message Syntax (CMS), obsolete)
* (Cryptographic Message Syntax, obsolete)
* (New ASN.1 Modules for Cryptographic Message Syntax (CMS) and S/MIME, in use)
* (New ASN.1 Modules for Cryptographic Message Syntax (CMS) and S/MIME, updated)
* (Using Elliptic Curve Cryptography with CMS, in use)
* (Use of Elliptic Curve Cryptography (ECC) Algorithms in Cryptographic Message Syntax (CMS), obsolete)
* (Using AES-CCM and AES-GCM Authenticated Encryption in the Cryptographic Message Syntax (CMS), in use)
Cryptographic protocols
Internet Standards
{{Crypto-stub