Feng Hao Sushmita Ruj Sourav Sen Gupta (Eds.) 8 9 8 Progress in Cryptology – 1 1 S C INDOCRYPT 2019 N L 20th International Conference on Cryptology in India Hyderabad, India, December 15–18, 2019 Proceedings Lecture Notes in Computer Science 11898 Founding Editors Gerhard Goos Karlsruhe Institute of Technology, Karlsruhe, Germany Juris Hartmanis Cornell University, Ithaca, NY, USA Editorial Board Members Elisa Bertino Purdue University, West Lafayette, IN, USA Wen Gao Peking University, Beijing, China Bernhard Steffen TU Dortmund University, Dortmund, Germany Gerhard Woeginger RWTH Aachen, Aachen, Germany Moti Yung Columbia University, New York, NY, USA More information about this series at http://www.springer.com/series/7410 Feng Hao Sushmita Ruj (cid:129) (cid:129) Sourav Sen Gupta (Eds.) – Progress in Cryptology INDOCRYPT 2019 20th International Conference on Cryptology in India – Hyderabad, India, December 15 18, 2019 Proceedings 123 Editors FengHao Sushmita Ruj University of Warwick CSIRO Data61 Warwick,UK Marsfield, NSW,Australia SouravSen Gupta Indian Statistical Institute NanyangTechnological University Kolkata, India Singapore, Singapore ISSN 0302-9743 ISSN 1611-3349 (electronic) Lecture Notesin Computer Science ISBN 978-3-030-35422-0 ISBN978-3-030-35423-7 (eBook) https://doi.org/10.1007/978-3-030-35423-7 LNCSSublibrary:SL4–SecurityandCryptology ©SpringerNatureSwitzerlandAG2019 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpartofthe material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilarmethodologynow knownorhereafterdeveloped. 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ThisSpringerimprintispublishedbytheregisteredcompanySpringerNatureSwitzerlandAG Theregisteredcompanyaddressis:Gewerbestrasse11,6330Cham,Switzerland Preface It is our great pleasure to present the proceedings of INDOCRYPT 2019, the 20th International Conference on Cryptology in India, held at the Novotel Hyderabad Convention Centre, Hyderabad, India, during December 15–18, 2019. This year marked two eventful decades of the INDOCRYPT conference series organized under the aegis of the Cryptology Research Society of India (CRSI). The conferencebeganin2000undertheleadershipofProf.BimalRoyofIndianStatistical Institute, Kolkata, and since then, this annual event has gained its place among pres- tigious cryptology conferences in the world. It is considered as the leading Indian venue on the subject. Over the last two decades, the conference took place in various cities of India—Kolkata (2000, 2006, 2012, 2016), Chennai (2001, 2004, 2007, 2011, 2017), Hyderabad (2002, 2010), New Delhi (2003, 2009, 2014, 2018), Bangalore (2005, 2015), Kharagpur (2008), and Mumbai (2013). This was the third time the conference was hosted in Hyderabad. INDOCRYPT 2019 attracted 110 submissions from 20 different countries. Out ofthese,papersthatwerewithdrawnbeforethedeadlineandtheonesthatviolatedthe submissionpolicy,werenotreviewed.Finally,90paperswerereviewednormallyby4 reviewers, with at least 3 reviewers per paper (2 in only 2 cases). The double-blind review phase was followed by a week-long discussion that generated additional commentsfromtheProgramCommitteemembersandtheexternalreviewers.Afterthe discussions,andaftershepherdinginafewcases,28paperswereacceptedforinclusion in the program, with authors from 14 different countries. These 28 papers were pre- sentedduringtheconference,andrevisedversionsofthesepapersareincludedinthese proceedings. In addition to the traditional presentations, the conference hosted a number of interesting short-talks and announcements during the Rump Session. The conference would not have been possible without the hard work of the 60 Program Committee members and the 69 external reviewers, who took part in the processofreviewingandsubsequentdiscussions.Wetakethisopportunitytothankthe Program Committee members and the external reviewers for their tremendous job in selecting the current program. It was an honor to work with them. The submissions, reviews, discussions, and proceedings were effectively managed using the EasyChair conference management system. We would also like to express our appreciation to Springer for their active cooperation and timely production of these conference proceedings. In addition to the contributed talks and the Rump Session, the program included three invited talks and two tutorials. Elaine Shi from Cornell University, USA, intro- duced“StreamlinedBlockchains:ASimpleandElegantApproach,”BartPreneelfrom KU Leuven, Belgium, discussed “Blockchain and Distributed Consensus: Hype or Science,” and Manoj Prabhakaran from IIT Bombay, India, spoke on “Extending the Foundations of Differential Privacy.” Tutorials by Satya Lokam, Microsoft Research, India, and Feng Hao, University of Warwick, UK, introduced the attendees to “Zero vi Preface KnowledgeProofsforFunandProfit”and“MorePracticalMulti-PartyComputation,” respectively. The abstracts of the invited talks and tutorials are also included in these proceedings. INDOCRYPT 2019 was conducted by C. R. Rao Advanced Institute of Mathe- matics, Statistics, and Computer Science (AIMSCS), jointly with University of Hyderabad (UoH), National Technical Research Organisation (NTRO), and Defence Research and Development Organization (DRDO). We are indebted to the general chairs, Anand Achuthan (ARCC), Siddani Bhaskara Rao (C. R. Rao AIMSCS), and DaggulaNarasimhaReddy(C.R.RaoAIMSCS),forsmoothlycoordinatingallmatters relatedtolocalorganizationoftheevent.Wewouldalsoliketothankthechiefpatrons, the organizing chairs, the organizing secretary, the treasurer, the convenors and co-convenors, and all members of the Organizing Committee, for their support in successfully hosting the conference in Hyderabad. We would also like to thank the teamatIndianStatisticalInstitute,Kolkata,formaintainingtheconferencewebsite,and the local organizing team at Hyderabad for their hard work to make the conference a success. We are especially grateful to our sponsors Department of Science and Technology (DST), Google, Microsoft Research India, Ministry of Electronics and Information Technology(MEITY),NationalBoardofHigherMathematics(NBHM),ReserveBank of India (RBI), and Robert Bosch Engineering and Business Solutions Pvt. Ltd, for their generous support towards the conference. Finally, we would like to thank each one of the 240 authors who submitted their work to INDOCRYPT 2019, and all the cryptology practitioners and enthusiasts who attendedtheevent. Without theirspirited participation,theconferencewouldnothave been a success. We hope you enjoy these proceedings of INDOCRYPT 2019. December 2019 Feng Hao Sushmita Ruj Sourav Sen Gupta Organization General Chairs Anand Achuthan Applied Research Centre for Cryptology, India Siddani Bhaskara Rao C. R. Rao AIMSCS, India Daggula Narasimha Reddy C. R. Rao AIMSCS, India Program Committee Chairs Feng Hao University of Warwick, UK Sushmita Ruj CSIRO Data61, Marsfield, NSW, Australia, and Indian Statistical Institute, Kolkata, India Sourav Sen Gupta Nanyang Technological University, Singapore Chief Patrons C. R. Rao (Founder) C. R. Rao AIMSCS, India C. Rangarajan RBI, India (Former Governor) V. K. Saraswat (Member) NITI Aayog, India Appa Rao P. (Vice-chancellor) University of Hyderabad, India Organizing Chairs C. E. Veni Madhavan C. R. Rao AIMSCS, India K. Narayana Murthy University of Hyderabad, India Web Chairs Prabal Banerjee Indian Statistical Institute, Kolkata, India Laltu Sardar Indian Statistical Institute, Kolkata, India Program Committee Anand Achuthan Applied Research Centre for Cryptology, India Divesh Aggarwal National University of Singapore, Singapore Diego F. Aranha Aarhus University, Denmark, and University of Campinas, Brazil Frederik Armknecht Universität Mannheim, Germany Man Ho Au The Hong Kong Polytechnic University, Hong Kong, China Daniel Augot Inria and École polytechnique, France viii Organization Samiran Bag The University of Warwick, UK Subhadeep Banik École Polytechnique Fédérale de Lausanne, Switzerland Rishiraj Bhattacharyya NISER Bhubaneswar, India Avik Chakraborti NTT, Japan Debrup Chakraborty Indian Statistical Institute, Kolkata, India Anupam Chattopadhyay Nanyang Technological University, Singapore Liqun Chen University of Surrey, UK Sherman S. M. Chow The Chinese University of Hong Kong, Hong Kong, China Michele Ciampi The University of Edinburgh, UK Mauro Conti University of Padua, Italy Nilanjan Datta Indian Statistical Institute, Kolkata, India Keita Emura National Institute of Information and Communications Technology, Japan Chaya Ganesh Aarhus University, Denmark Esha Ghosh Microsoft Research, Redmond, USA Feng Hao The University of Warwick, UK Martin Hell Lund University, Sweden Xinyi Huang Fujian Normal University, China Takanori Isobe University of Hyogo, Japan Bhavana Kanukurthi Indian Institute of Science, Bengaluru, India Aniket Kate Purdue University, USA Ayesha Khalid Queen’s University Belfast, UK Kaoru Kurosawa Ibaraki University, Japan Alptekin Küpçü Koç University, Turkey Kwok Yan Lam Nanyang Technological University, Singapore Kaitai Liang University of Surrey, UK Joseph Liu Monash University, Australia Zhe Liu Nanjing University of Aeronautics and Astronautics, China Subhamoy Maitra Indian Statistical Institute, Kolkata, India Mary Maller University College London, UK Giorgia Azzurra Marson NEC Laboratories Europe, Germany Tarik Moataz Brown University, USA Pratyay Mukherjee Visa Research, Palo Alto, USA Shishir Nagaraja University of Strathclyde, UK Seetharam Narasimhan Intel Corporation, USA Rajesh Pillai DRDO, India Shashwat Raizada Robert Bosch Engineering and Business Solutions Private Limited, India Somindu Chaya Ramanna Indian Institute of Technology, Kharagpur, India Chester Rebeiro Indian Institute of Technology, Madras, India Mike Rosulek Oregon State University, USA Sushmita Ruj CSIRO Data61, Marsfield, NSW, Australia, and Indian Statistical Institute, Kolkata, India Organization ix Reihaneh Safavi-Naini University of Calgary, Canada Kouichi Sakurai Kyushu University, Japan Santanu Sarkar Indian Institute of Technology, Madras, India Sumanta Sarkar TCS Innovation Labs, India Peter Schwabe Radboud University, The Netherlands Sourav Sen Gupta Nanyang Technological University, Singapore Binanda Sengupta Singapore Management University, Singapore Siamak Shahandashti University of York, UK Maliheh Shirvanian Visa Research, Palo Alto, USA Sujoy Sinha Roy University of Birmingham, UK Willy Susilo University of Wollongong, Australia Alwen Tiu The Australian National University, Australia Qingju Wang University of Luxembourg, Luxembourg Kan Yasuda NTT, Japan Jiangshan Yu Monash University, Australia Bin Zhang Chinese Academy of Sciences, China Bingsheng Zhang Lancaster University, UK Additional Reviewers Aghili, Seyed Farhad Gupta, Indivar Agrawal, Shashank Han, Runchao Anada, Hiroaki Hubáček, Pavel Anshu, Anurag Huguenin-Dumittan, Loïs Baksi, Anubhab Inoue, Akiko Balli, Fatih İşler, Devriş Bao, Zhenzhen Jana, Amit Barooti, Khashayar Karati, Sabyasachi Biçer, Osman Khairallah, Mustafa Chakraborty, Kaushik Kumar Singh, Nikhilesh Charpin, Pascale Kumar, Nishant Chatterjee, Sanjit Kumar, Satyam Cheng, Chen-Mou Kumar, Yogesh Choi, Gwangbae Kundu, Samir Costa Massolino, Pedro Maat Larangeira, Mario Daemen, Joan Li, Wei Dalai, Deepak Lin, Chao Dey, Chandan Lin, Fuchun Dobraunig, Christoph Liu, Fukang Dutta, Avijit Livsey, Lee Dutta, Sabyasachi Ma, Jack P. K. Fauzi, Prastudy Ma, Jinhua Ferradi, Houda Mancillas-López, Cuauhtemoc Ge, Chunpeng Matsuda, Takahiro Ghosh, Satrajit Meier, Willi