GB/T 36624-2018Information technology -- Security techniques -- Authenticated encryption (English PDF)

Foreword

This Standard was drafted in accordance with the rules in GB/T 1.1-2009.

This Standard adopts the re-drafting law to modify the adoption of ISO/IEC 19772.2009

Information Technology - Security Techniques - Authenticated Encryption.

In comparison with ISO/IEC 19772.2009, the technical differences and the causes for

these differences are as follows.

---In regard to normative references, this Standard makes adjustments with

technical differences, so as to adapt to the technical conditions of China. The

adjustments are concentratedly reflected in Chapter 2 "Normative References".

The specific adjustments are as follows.

 GB/T 15852.1-2008, which equivalently adopts the international standard,

is used to replace ISO/IEC 9797-1 (see 8.4);

 GB/T 17964-2008 is used to replace ISO/IEC 10116 (see 9.3);

 GB/T 32907-2016 is used to replace ISO/IEC 18033-3 (see Chapter 5);

 GB/T 25069-2010 is added to the references (see Chapter 3);

---In Chapter 3, terms and definitions that have already been defined in the current

national standards are directly adopted; some common definitions are deleted.

In comparison with ISO/IEC 19772.2009, there are relatively significant adjustments in

structure. See the details below.

---The content of Scope in ISO/IEC 19772.2009 is modified; some content is

transferred to Chapter 5 Overview;

---In consideration of the practical application scope of China's national conditions

technology, this Standard adopts the five authenticated encryption mechanisms

specified in Chapter 7 ~ Chapter 11 in ISO/IEC 19772.2009; deletes the

authenticated encryption mechanism specified in Chapter 6 in ISO/IEC

19772.2009;

---Normative Appendix C in ISO/IEC 19772.2009 is adjusted to Appendix A,

correspondingly, Informative Appendix A and Appendix B in ISO/IEC

1 Scope

This Standard specifies five authenticated encryption mechanisms, which achieve the

following security objectives by defining the methods of processing a data string.

2 Normative References

The following documents are indispensable to the application of this document. In

terms of references with a specified date, only versions with a specified date are

applicable to this document. In terms of references without a specified date, the latest

version (including all the modifications) is applicable to this document.

GB/T 15852.1-2008 Information Technology - Security Techniques - Message

Authentication Codes (MACs) - Part 1.Mechanisms Using a Block Cipher (ISO/IEC

9797-1.1999, IDT)

3 Terms and Definitions

What is defined in GB/T 15852.1-2008, GB/T 17964-2008 and GB/T 25069-2010, and

the following terms and definitions are applicable to this document.

4 Symbols

The following symbols are applicable to this document.

5 Overview

The five authenticated encryption mechanisms specified in this Standard are all based

on the block cipher algorithm. Meanwhile, the data originator and data recipient are

required to share keys.

6 Authenticated Encryption Mechanism 1

The block cipher algorithm used in this mechanism shall be a 128-bit block cipher

algorithm, namely, n = 128.This mechanism requires that the protected data D shall

at least contain 128 bits, and the data length shall be an integer multiple of 64 bits

[namely, len(D) = 64m, m > 1].

7 Authenticated Encryption Mechanism 2

Before using this authenticated encryption mechanism, the data originator and data

recipient shall firstly negotiate and determine the following matters.

8 Authenticated Encryption Mechanism 3

Before using this authenticated encryption mechanism, the data originator and

recipient shall firstly determine the standard length t, in which, 0 < t <= n.

The recipient shall execute the following steps to decrypt and verify the authenticated

encrypted data C.

9 Authenticated Encryption Mechanism 4

Before using this authenticated encryption mechanism, the data originator and data

recipient shall firstly negotiate and determine the following matters.

10 Authenticated Encryption Mechanism 5

Before using this authenticated encryption mechanism, the data originator and

recipient shall firstly negotiate and determine the tag length t. The value of t shall be

an integer multiple of 8 and satisfy 96 <= t <= 128 (under specific circumstances, the

value of t may also be 32 or 64).

Appendix A

(normative)

ASN.1 Module

The five authenticated encryption mechanisms specified in this Standard are

respectively corresponding to ae-mechanism2, ae-mechanism3, ae-mechanism4, ae-

mechanism5 and ae-mechanism6 in the above ASN.1 definition.

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