IACR News item: 21 March 2025

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Hit enter to search with Google.</p> <form action="/search" method="GET"> <input id="searchboxMobile" name="q" type="search" class="form-control border searchBoxes" placeholder="Search IACR"/> </form> </div> </div> </nav> </div>  </div> <main id="iacrMain-contentBox" class="container px-md-4 py-3"> <section class="row"> <div class="col-12"> <h2> IACR News item: 21 March 2025 </h2> </div> </section> <div class="card newsItemBox" id="item-25339"> <div class="card-header pb-1"> <a id="item-url-25339" href="https://eprint.iacr.org/2025/523"> <h5 id="item-headline-25339"> Assembly optimised Curve25519 and Curve448 implementations for ARM Cortex-M4 and Cortex-M33 </h5> </a> </div> <div class="card-body"> <div class="d-flex"> <h6 class="card-title newsCardSubtitle mt-1 mr-auto" id="item-subheadline-25339"> Emil Lenngren </h6> <img id="item-icon-25339" src="/img/icons/news/channel_10.svg" class="pl-1 newsCategoryIcon d-none d-md-block" title="ePrint Report channel" alt="ePrint Report" /> <span id="item-priority-25339" class="badge badge-dark priority5" title="ePrint Report channel">ePrint Report</span> </div> <div id="item-body-25339" class="card-text item-body"> Since the introduction of TLS 1.3, which includes X25519 and X448 as key exchange algorithms, one could expect that high efficient implementations for these two algorithms become important as the need for power efficient and secure IoT devices increases. Assembly optimised X25519 implementations for low end processors such as Cortex-M4 have existed for some time but there has only been scarce progress on optimised X448 implementations for low end ARM processors such as Cortex-M4 and Cortex-M33. This work attempts to fill this gap by demonstrating how to design a constant time X448 implementation that runs in 2 273 479 cycles on Cortex-M4 and 2 170 710 cycles on Cortex-M33 with DSP. An X25519 implementation is also presented that runs in 441 116 cycles on Cortex-M4 and 411 061 cycles on Cortex-M33 with DSP. </div><span class="btn-link text-right expand-button body-expand">Expand</span> </div> </div> <div class="mt-4"> <p> Additional news items may be found on the <a href="/news/">IACR news page</a>. </p> </div> </main> <div id="pageFooter"> <footer class="container-fluid iacrMain-footer pt-4"> <div class="row px-4"> <div class="col-12 col-md-6 col-lg-3 mb-md-3"> <a href="/about/" class="h6 d-none d-md-block"> <strong>About</strong> </a> <p class="d-none d-md-block mt-2"> The <a href="/">International Association for Cryptologic Research (IACR)</a> is a non-profit scientific organization whose purpose is to further research in cryptology and related fields. <a href="/about/">Learn more...</a> </p> <div class="text-center"> <a href="//twitter.com/IACR_News" class="social" title="Twitter Feed"> <img src="/img/icons/twitter.svg" class="socialBtn" alt="Twitter logo"> </a> <a href="//youtube.com/TheIACR" class="social" title="YouTube Channel"> <img src="/img/icons/youtube.svg" class="socialBtn" alt="YouTube logo"> </a> <a href="//www.facebook.com/theiacr/" class="social" title="Facebook Page"> <img src="/img/icons/facebook.svg" class="socialBtn" alt="Facebook logo"> </a> <a href="https://weibo.com/iacr" class="social" title="Weibo"> <img src="/img/icons/weibo.svg" class="socialBtn" alt="Weibo logo"> </a> </div> </div> <div class="col-12 col-md-6 col-lg-3"> <a href="/meetings/" class="h6"> <strong>Events</strong> </a> <ul class="list-unstyled"> <li> <a href="/meetings/asiacrypt/">Asiacrypt</a>  •  <a href="/meetings/crypto/">Crypto</a>  •  <a href="/meetings/eurocrypt/">Eurocrypt</a> </li> <li> <a href="/meetings/ches/" title="Cryptographic Hardware and Embedded Systems">CHES</a>  •  <a href="/meetings/fse/" title="Fast Software Encryption">FSE</a>  •  <a href="/meetings/pkc/" title="Public Key Cryptography">PKC</a>  •  <a href="/meetings/tcc/" title="Theory of Cryptography Conference">TCC</a> </li> <li> <a href="//rwc.iacr.org/"> Real World Crypto </a> </li> <li> <a href="/schools/"> Schools </a> </li> <li> <a href="/events/"> Calendar of events </a> </li> </ul> </div> <div class="col-12 col-md-6 col-lg-3"> <a href="/publications/" class="h6"> <strong>Publications</strong> </a> <ul class="list-unstyled"> <li> <a href="/publications/access.php"> Access to Publications </a> </li> <li> <a href="/jofc/"> Journal of Cryptology </a> </li> <li> <a href="/transactions/tosc/"> Trans. on Symmetric Cryptology </a> </li> <li> <a href="https://tches.iacr.org/"> Trans. on CHES </a> </li> <li> <a href="https://cic.iacr.org/"> Communications in Cryptology </a> </li> <li> <a href="//eprint.iacr.org/"> Cryptology ePrint Archive </a> </li> <li> <a href="/cryptodb/"> Publication database </a> </li> </ul> </div> <div class="col-12 col-md-6 col-lg-3"> <a href="/services/" class="h6"> <strong>Services</strong> </a> <ul class="list-unstyled"> <li> <a href="/news"> News </a> </li> <li> <a href="/awards/"> Awards </a> </li> <li> <a href="/jobs/"> Jobs </a> </li> <li> <a href="https://register.iacr.org/membership/members/">Update your information</a> </li> <li> <a href="/membership.php">How to join</a> </li> <li class="d-block d-md-none"> <a href="/about/"> About the IACR </a> </li> </ul> </div> </div> <div class="row"> <div class="col-12 iacrMain-bottomOfFooter text-center py-2 mt-3"> <span class="align-middle"> <a href="/copyright.html">Copyright © <span id="thisYear"></span> <script>document.getElementById("thisYear").innerHTML = new Date().getFullYear();</script> <span class="d-none d-md-inline">by the </span><span class="d-md-none">IACR</span><span class="d-none d-md-inline">International Association for Cryptologic Research</span></a> <span class="d-none d-md-inline">• </span><br class="d-md-none"> <a href="/privacy.html">Privacy Policy</a> </span> </div> </div> </footer>  </div> <script src="https://iacr.org/libs/js/jquery/3.3.1/jquery.min.js"></script> <script src="https://iacr.org/libs/css/bootstrap/dist/js/bootstrap.bundle.min.js"></script> <script src="https://iacr.org/libs/js/easy-autocomplete/jquery.easy-autocomplete.js"></script>  <script src="/js/search.js"></script> </body> </html>

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IACR News item: 21 March 2025