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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">mais</journal-id><journal-title-group><journal-title xml:lang="ru">Моделирование и анализ информационных систем</journal-title><trans-title-group xml:lang="en"><trans-title>Modeling and Analysis of Information Systems</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1818-1015</issn><issn pub-type="epub">2313-5417</issn><publisher><publisher-name>Yaroslavl State University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.18255/1818-1015-2018-6-589-606</article-id><article-id custom-type="elpub" pub-id-type="custom">mais-761</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>Оригинальные статьи</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>Articles</subject></subj-group></article-categories><title-group><article-title>Даже простые процессы π-исчисления трудны для анализа</article-title><trans-title-group xml:lang="en"><trans-title>Even Simple Processes of π-calculus are Hard for Analysis</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-8019-7090</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Аббас</surname><given-names>Марат Мазен</given-names></name><name name-style="western" xml:lang="en"><surname>Abbas</surname><given-names>Marat M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>студент</p><p>Ленинские горы, 1, г. Москва, 119991</p></bio><bio xml:lang="en"><p>student</p><p>GSP-1, Leninskie Gory, Moscow, 119991</p></bio><email xlink:type="simple">unlock96@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3794-9565</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Захаров</surname><given-names>Владимир Анатольевич</given-names></name><name name-style="western" xml:lang="en"><surname>Zakharov</surname><given-names>Vladimir A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>доктор физ.-мат. наук, профессор</p><p>ул. Мясницкая, 20, г. Москва, 101000</p><p>ул. А. Солженицына, 25, 109004, г. Москва</p></bio><bio xml:lang="en"><p>Dr. of Science, professor</p><p>20 Myasnitskaya st., Moscow, 101000</p><p>25 Alexander Solzhenitsyn st., Moscow, 109004</p></bio><email xlink:type="simple">zakh@cs.msu.ru</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Московский государственный университет им. М.В. Ломоносова</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Lomonosov Moscow State University</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Национальный исследовательский университет «Высшая школа экономики»;&#13;
Институт системного программирования им. В.П. Иванникова РАН</institution><country>Россия</country></aff><aff xml:lang="en"><institution>National Research University Higher School of Economics (HSE);&#13;
Institute for system programming of the Russian Academy of Science (ISP RAS)</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2018</year></pub-date><pub-date pub-type="epub"><day>19</day><month>12</month><year>2018</year></pub-date><volume>25</volume><issue>6</issue><fpage>589</fpage><lpage>606</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Аббас М.М., Захаров В.А., 2018</copyright-statement><copyright-year>2018</copyright-year><copyright-holder xml:lang="ru">Аббас М.М., Захаров В.А.</copyright-holder><copyright-holder xml:lang="en">Abbas M.M., Zakharov V.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.mais-journal.ru/jour/article/view/761">https://www.mais-journal.ru/jour/article/view/761</self-uri><abstract><p>Математические модели распределенных вычислений, построенные на основе исчисления мобильных процессов (\(π\)-исчисления), широко используются для проверки свойств информационной безопасности криптографических протоколов. Поскольку \(π\)-исчисление является полной по Тьюрингу моделью вычислений, эта задача в общем случае алгоритмически неразрешима. Поэтому ее исследование проводится лишь для некоторых специальных классов процессов \(π\)-исчисления с ограниченными вычислительными возможностями, например, для нерекурсивных процессов, в которых все вычисления имеют ограниченную длину, для процессов с ограниченным числом параллельных компонентов и др. Однако и в этих случаях предложенные разрешающие алгоритмы оказываются весьма трудоемкими. Мы полагаем, что это обусловлено самой природой процессов \(π\)-исчисления. Цель данной работы — показать, что даже для наиболее слабой модели пассивного противника и для сравнительно простых протоколов, в которых используются лишь базовые операции \(π\)-исчисления, задача проверки свойств информационной безопасности этих протоколов является co-NP-полной.</p></abstract><trans-abstract xml:lang="en"><p>Mathematical models of distributed computations, based on the calculus of mobile processes (π-calculus) are widely used for checking the information security properties of cryptographic protocols. Since π-calculus is Turing-complete, this problem is undecidable in general case. Therefore, the study is carried out only for some special classes of π-calculus processes with restricted computational capabilities, for example, for non-recursive processes, in which all runs have a bounded length, for processes with a bounded number of parallel components, etc. However, even in these cases, the proposed checking procedures are time consuming. We assume that this is due to the very nature of the π -calculus processes. The goal of this paper is to show that even for the weakest model of passive adversary and for relatively simple protocols that use only the basic π-calculus operations, the task of checking the information security properties of these protocols is co-NP-complete.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>π-исчисление</kwd><kwd>протокол</kwd><kwd>безопасность</kwd><kwd>пассивный противник</kwd><kwd>верификация</kwd><kwd>сложность</kwd><kwd>NP-полнота</kwd></kwd-group><kwd-group xml:lang="en"><kwd>π-calculus</kwd><kwd>protocol</kwd><kwd>security</kwd><kwd>passive adversary</kwd><kwd>verification</kwd><kwd>complexity</kwd><kwd>NP-completeness</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">РФФИ N 18-01-00854, РФФИ N 16-01-00714</funding-statement><funding-statement xml:lang="en">Grant N 18-01-00854, Grant N 16-01-00714</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Abadi M., Gordon A.D., “A Calculus for Cryptographic Protocols: The Spi Calculus”, Information and Computation, 148:1 (1999), 1–70.</mixed-citation><mixed-citation xml:lang="en">Abadi M., Gordon A.D., “A Calculus for Cryptographic Protocols: The Spi Calculus”, Information and Computation, 148:1 (1999), 1–70.</mixed-citation></citation-alternatives></ref><ref id="cit2"><label>2</label><citation-alternatives><mixed-citation xml:lang="ru">Abadi M., Fournet C., “Mobile Values, New Names, and Secure Communication”, Proceedings of the 28-th ACM Symposium on Principles of Programming Languages, 2001, 104–115.</mixed-citation><mixed-citation xml:lang="en">Abadi M., Fournet C., “Mobile Values, New Names, and Secure Communication”, Proceedings of the 28-th ACM Symposium on Principles of Programming Languages, 2001, 104–115.</mixed-citation></citation-alternatives></ref><ref id="cit3"><label>3</label><citation-alternatives><mixed-citation xml:lang="ru">Amadio M.R., Lugiez D., “On the Reachability Problem for Cryptographic Protocols”, Proceedings of the 11-th International Conference on Concurrency Theory, 2000, 380–394.</mixed-citation><mixed-citation xml:lang="en">Amadio M.R., Lugiez D., “On the Reachability Problem for Cryptographic Protocols”, Proceedings of the 11-th International Conference on Concurrency Theory, 2000, 380–394.</mixed-citation></citation-alternatives></ref><ref id="cit4"><label>4</label><citation-alternatives><mixed-citation xml:lang="ru">Amadio M.R., Lugiez D., Vanackere V., “On the symbolic reduction of processes with cryptographic functions”, Theoretical Computer Science, 290:1 (2003), 695–740.</mixed-citation><mixed-citation xml:lang="en">Amadio M.R., Lugiez D., Vanackere V., “On the symbolic reduction of processes with cryptographic functions”, Theoretical Computer Science, 290:1 (2003), 695–740.</mixed-citation></citation-alternatives></ref><ref id="cit5"><label>5</label><citation-alternatives><mixed-citation xml:lang="ru">Arapinis M., Liu J., Ritter E., Ryan M., “Stateful Applied Pi Calculus”, Proceedings of the Principles of Security and Trust—Third International Conference, 2014, 22–41.</mixed-citation><mixed-citation xml:lang="en">Arapinis M., Liu J., Ritter E., Ryan M., “Stateful Applied Pi Calculus”, Proceedings of the Principles of Security and Trust—Third International Conference, 2014, 22–41.</mixed-citation></citation-alternatives></ref><ref id="cit6"><label>6</label><citation-alternatives><mixed-citation xml:lang="ru">Blanchet B., Smith B., “Automated reasoning for equivalences in the applied pi calculus with barriers”, Proceedings of the 29-th IEEE Computer Security Foundations Symposium, 2014, 310–324.</mixed-citation><mixed-citation xml:lang="en">Blanchet B., Smith B., “Automated reasoning for equivalences in the applied pi calculus with barriers”, Proceedings of the 29-th IEEE Computer Security Foundations Symposium, 2014, 310–324.</mixed-citation></citation-alternatives></ref><ref id="cit7"><label>7</label><citation-alternatives><mixed-citation xml:lang="ru">Bodei C., Degano P., Nielson F., Nielson H. 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