INTERNATIONAL ISO/IEC STANDARD 18033-6 First edition 2019-05 IT Security techniques Encryption algorithms - Part 6: Homomorphic encryption Techniques de sécurite IT - Algorithmes de chiffrement - Partie 6: Chiffrement homomorphe Reference number IEC ISO/IEC 18033-6:2019(E) os1 @IS0/IEC 2019 IS0/IEC 18033-6:2019(E) COPYRIGHTPROTECTEDDOCUMENT IS0/IEC 2019 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: +4122 749 0111 Fax: +41 22 749 09 47 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0/IEC 2019 - All rights reserved IS0/IEC 18033-6:2019(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. ..1 2 Normative references ..1 3 Terms and definitions 4 Symbols and abbreviations .3 5 General model for homomorphic encryption 5.1 Entities. .4 5.2 Key roles.... ..4 5.3 Algorithms .4 5.4 Functional requirements .4 6 Homomorphic encryption mechanisms .5 6.1 General .5 6.2 Exponential ElGamal encryption .5 6.2.1 General. 5 6.2.2 Key generation algorithm .5 6.2.3 Encryption 5 6.2.4 Decryption. .6 6.3 Paillier encryption .6 6.3.1 General .6 6.3.2 Key generation algorithm .7 6.3.3 Encryption.. .7 6.3.4 Decryption. Annex A (normative) Object identifiers .9 Annex B (informative) Numerical examples .10 Bibliography ..17 @ IS0/IEC 2019 - All rights reserved iii