GB/T 35275-2026Cybersecurity technology — SM2 cryptographic algorithm encryption and signature message format (English PDF)

1 Scope

This document specifies the message format for the SM2 cryptographic algorithm in cryptographic signatures.

This document is applicable to encapsulating the results of cryptographic signature operations using the SM2 cryptographic algorithm.

4 Abbreviations

The following abbreviations apply to this document. OID. Object Identifier

5 Overview

The ContentInfo type is used to represent the general syntax structure for content exchange, and its definition is as follows. contentType ContentType, content [0]EXPLICITANYDEFINEDBYcontentTypeOPTIONAL ContentType::=OBJECTIDENTIFIER in. contentType indicates the type of content.

The content is optional, and its content type is indicated by contentType.

The ContentInfo object is used to represent the eight data types involved in the SM2 cryptographic algorithm's encrypted signature. Data, SignedData,... EnvelopedData,SignedAndEnvelopedData,EncryptedData,KeyAgreementInfo,DigestedData and The identifier for AuthEnvelopedData is defined. Its object identifier is shown in Table 1. Chapter 6 of this document specifies the above eight types. The basic type definitions used.

6 Basic Type Definitions

7 Data Types

The Data data structure is defined as follows. Data. OCTETSTRING Data represents any string of bytes.

The `signedData` data type consists of data of any type and a signature value from at least one signer. Data of any type can be simultaneously... It can be signed by any number of signers. See Appendix A, section A.1 for examples of signature data types.

The envelopedData data type of a digital envelope consists of encrypted data and ciphertext containing the encryption key of at least one recipient.

In this context, encrypted data is encrypted using a data encryption key, which in turn is encrypted using the recipient's public key.

See A.2 for an example of a digital envelope data type.

The DigestedData data type consists of data of any type and a message digest of it. See A.3 for an example of the DigestedData data type.

The EncryptedData data type consists of encrypted data of any type; this data type has neither a receiver nor encryption capability.

Data encryption key. See A.4 for an example of encrypted data types.

The AuthEnvelopedData data type consists of ciphertext containing authentication digital envelope data and at least one recipient's authentication digital envelope key.

Composition. The authEnvelopedData data type provides both confidentiality and integrity; see A.5 for an example of identifying the digital envelope data type.

8 SignedData data type

9 Digital Envelope Data Type (EnvelopedData)

10 DigestedData Data Type

11 Encrypted Data Type

12 Identify the data type of the digital envelope