ISO/IEC 18033-3:2010/DAmd 1

SM4

Standards Content (sample)

DRAFT AMENDMENT
ISO/IEC 18033-3:2010/DAM 1
ISO/IEC JTC 1/SC 27 Secretariat: DIN
Voting begins on: Voting terminates on:
2020-11-30 2021-02-22
Information technology — Security techniques —
Encryption algorithms —
Part 3:
Block ciphers
AMENDMENT 1: SM4

Technologies de l'information — Techniques de sécurité — Algorithmes de chiffrement —

Partie 3: Chiffrement par blocs
AMENDEMENT 1
ICS: 35.030
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
This document is circulated as received from the committee secretariat.
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/IEC 18033-3:2010/DAM 1:2020(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. ISO/IEC 2020
---------------------- Page: 1 ----------------------
ISO/IEC 18033-3:2010/DAM 1:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2020

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO/IEC 2020 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/IEC 18033-3:2010/DAM 1:2020(E)
Foreword

ISO (the International Organization for Standardization) and IEC (the International Electrotechnical

Commission) form the specialized system for worldwide standardization. National bodies that are

members of ISO or IEC participate in the development of International Standards through technical

committees established by the respective organization to deal with particular fields of technical

activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international

organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the

work. In the field of information technology, ISO and IEC have established a joint technical committee,

ISO/IEC JTC 1.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for

the different types of document should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject

of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent

rights. Details of any patent rights identified during the development of the document will be in the

Introduction and/or on the ISO list of patent declarations received (see www .iso .org/ patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment,

as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the

Technical Barriers to Trade (TBT) see the following URL www .iso .org/ iso/ foreword .html.

The committee responsible for this document is ISO/IEC JTC 1, Information technology, Subcommittee

SC 27, Information security, cybersecurity and privacy protection.
© ISO/IEC 2020 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO/IEC 18033-3:2010/DAM 1:2020(E)
Information technology — Security techniques —
Encryption algorithms —
Part 3:
Block ciphers
AMENDMENT 1: SM4
AA: Clause 1:
Change the following sentence of paragraph 1:
A total of seven different block ciphers are defined.
to:
A total of eight different block ciphers are defined.
BB: Clause 1, Table 1:
Replace Table 1 with the following:
Block length Algorithm name (see #) Key length
TDEA (4.2) 128 or 192 bits
MISTY (4.3)
64 bits
CAST-128 (4.4) 128 bits
HIGHT (4.5)
AES (5.2)
128, 192 or 256
bits
Camellia (5.3)
128 bits
SEED (5.4) 128 bits
SM4 (5.5) 128 bits
CC: 5.1:
Change the following sentence of paragraph 1:

In this clause 5, three 128-bit block ciphers are specified; AES in 5.2, Camellia in 5.3, and SEED in 5.4.

to:

In this clause, four 128-bit block ciphers are specified; AES in 5.2, Camellia in 5.3, SEED in 5.4, and

SM4 in 5.5.
DD: After 5.4.5:
Add the following new 5.5 thru 5.5.5 to the end of 5.4.5:
© ISO/IEC 2020 – All rights reserved 1
---------------------- Page: 4 ----------------------
ISO/IEC 18033-3:2010/DAM 1:2020(E)
5.5 SM4
5.5.1 The SM4 algorithm

The SM4 algorithm is a symmetric block cipher that can process data blocks of 128 bits, using a cipher

key with length of 128 bits under 32 rounds.
5.5.2 SM4 encryption

A 128-bit block P is transformed into a 128-bit block C using the following procedure, where for i = 0, 1,

2, 3 the X are 32-bit variables, and for i = 0, 1, …, 31 the rk are 32-bit subkeys:

i i
(1) P = X || X || X || X
0 1 2 3
(2) for i = 0 to 31:
X = F(X , X , X , X , rk )
i+4 i i+1 i+2 i+3 i
(3) C = X || X || X || X
35 34 33 32
5.5.3 SM4 decryption

The decryption operation is identical to the encryption operation, except that the rounds (and therefore

the subkeys) are used in reverse order:
(1) C = X || X || X || X
35 34 33 32
(2) for i = 31 to 0:
X = F(X , X , X , X , rk )
i i+4 i+1 i+2 i+3 i
(3) P = X || X || X || X
0 1 2 3
5.5.4 SM4 functions
5.5.4.1 Function F

The function F is used for both encryption and decryption. The function F is defined as follows:

F(X , X , X , X , rk) = X ⊕T(X ⊕X ⊕X ⊕rk)
0 1 2 3 0 1 2 3

where X (i = 0, 1, 2, 3) and rk are bit strings of length 32, T is a permutation defined in 5.5.4.2.

5.5.4.2 Permutation T and T’
5.5.4.2
...