ISO INTERNATIONAL STANDARD 20038 First edition 2017-11 Banking and related financial services - Key wrap using AES Banque et autres services financiers Enveloppe de cle utilisant AEs Reference number IS0 20038:2017(E) osi @IS02017 IS0 20038:2017(E) COPYRIGHT PROTECTED DOCUMENT @ IS0 2017, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form writtenpermission.Permission canberequestedfromeitherIsOattheaddressbelow orIso'smemberbodyinthecountryof the requester. ISO copyrightoffice 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 ii @ IS0 2017 - All rights reserved IS0 20038:2017(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. ..1 2 Normative references 3 Terms and definitions 4 Symbols and abbreviated terms 5 Key wrap method characteristics ..3 6 Key Block Binding key wrap method ..3 6.1 General ..3 6.2 Key block binding and encryption .4 6.3 Key derivation.. .5 6.4 Key Block Decryption and MAC Validation Annex A (normative) Key Block with Optional Block ..8 Annex B (informative) Numerical example .19 Bibliography .22 @ IS0 2017 - All rights reserved iii