INTERNATIONAL ISO/IEC STANDARD 18370-2 First edition 2016-07-01 Information technology Security techniques - Blind digital signatures - Part 2: Discrete logarithm based mechanisms Technologie de I'information - Techniques de sécurité - Signatures numeriques en aveugle - Partie 2: Mécanismes fondés sur le logarithme discret Reference number IS0/IEC 18370-2:2016(E) IEC International Organization for Standardization G INST OF STANDARDIZATION C1 5956617 @ IS0/IEC 2016 ed without license from IHS IS0/IEC 18370-2:2016(E) COPYRIGHT PROTECTEDDOCUMENT IS0/IEC 2016, Published in Switzerland All rights reserved. Unless otherwise specified, 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 Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 [email protected] www.iso.org Licensee-ZHEJIANG INST OF STANDRJSA/IEC 6 - All rights reserved Not for Resale, 2016/8/16 08:36:25 networking permited without license from IHS IS0/IEC 18370-2:2016(E) Contents Page Foreword ..V Introduction. ...vi 1 Scope. 2 Normative references 3 Terms and definitions 4 Symbols. 5 General requirements ..4 6 Blind signature mechanisms 6.1 General ..4 6.2 Mechanism 1 ..4 6.2.1 Security parameters. .4 6.2.2 Key generation process ..5 6.2.3 Blind signature process. .5 6.2.4 Verification process. .6 1 Blind signature mechanisms with partial disclosure 7.1 General .6 7.2 Mechanism 2 ..6 7.2.1 Security parameters .6 7.2.2 Key generation process ..6 7.2.3 Blind signature process with partial disclosure 7 7.2.4 Verification process. ..8 7.3 .8 Mechanism 3 7.3.1 Symbols. .8 7.3.2 Key generation process ..8 7.3.3 Blind signature process with partial disclosure .9 7.3.4 Verification proces... ..9 8 Blind signature mechanisms with selective disclosure ..10 8.1 General .10 8.2 Mechanism 4 ..10 8.2.1 Security parameters. .10 8.2.2 Key generation process 10 8.2.3 Blind signature process with selective disclosure ..10 8.2.4 Presentation process. ..12 8.2.5 Verification process. ..12 9 Traceable blind signature mechanisms ..13 9.1 General ..13 9.2 Mechanism 5 ..13 9.2.1 Symbols. .13 9.2.2 Key generation process 9.2.3 Traceable blind signature process .14 9.2.4 Verification process... ..16 9.2.5 Requestor tracing process. .16 9.2.6 Signature tracing process. 9.2.7 Requestor tracing evidence evaluation process ..17 9.2.8 Signature tracing evidence evaluation process. ..17 AnnexA(normative)Objectidentifiers ..19 Annex B (normative) Conversion functions. ..20 Annex C (normative) Group description .21 Annex D (informative) Special hash-functions ..22 Inteainal oganzaon @SISGa/LECG, 2016 - All rights reserved iii icensee=ZHEJIANG INST OF STANDARDIZATION C1 5956617 ed without license from IHS IS0/IEC 18370-2:2016(E) Annex E (informative) Security considerations and comparison of blind signature mechanisms .24 Annex F (informative) Numerical examples .26 Bibliography .78 nse-ZHEJIANG INST OF STANDRJSQ/IEC 6 - All rights reserved No reproduction or networking permitted without license from IHS vided by IHS unde IS0/IEC 18370-2:2016(E) Foreword IsO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission)formthespecializedsystemforworldwidestandardization.Nationalbodiesthatare 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 th