{"id":2889,"date":"2026-09-08T06:57:12","date_gmt":"2026-09-08T13:57:12","guid":{"rendered":"https:\/\/self-issued.info\/?p=2889"},"modified":"2026-09-08T06:57:12","modified_gmt":"2026-09-08T13:57:12","slug":"openid-connect-token-hash-algorithm-implementers-guide-published","status":"publish","type":"post","link":"https:\/\/self-issued.info\/?p=2889","title":{"rendered":"OpenID Connect Token Hash Algorithm Implementer&#8217;s Guide Published"},"content":{"rendered":"<p><span class=\"plain\"><img decoding=\"async\" align=\"right\" alt=\"OpenID logo\" src=\"http:\/\/self-issued.info\/images\/openid-logo.png\"><\/span>The <a href=\"https:\/\/openid.net\/wg\/connect\/\">OpenID Connect working group<\/a> has published the initial version of the <a href=\"https:\/\/openid.net\/specs\/openid-connect-token-hash-algorithms-1_0.html\">OpenID Connect Token Hash Algorithm Implementer&#8217;s Guide 1.0<\/a>.  Thanks to <a href=\"https:\/\/www.linkedin.com\/in\/filipskokan\/\">Filip Skokan<\/a> for writing this.  Quoting from the Abstract:<\/p>\n<blockquote><p>\nThis OpenID Connect Token Hash Algorithm Implementer&#8217;s Guide 1.0 identifies the hash algorithms to use when calculating OpenID Connect ID Token hash claims, such as <code>at_hash<\/code> and <code>c_hash<\/code>, Financial-grade API <code>s_hash<\/code>, and profile-defined token hash claims, for JWS algorithms whose hash function is not completely determined by the algorithm identifier in JSON Web Algorithms (JWA) [JWA].<\/p>\n<p>This guide records implementation guidance for existing and registered JWS algorithm identifiers. It is intended to remain open for maintenance and is not intended to advance to Final Specification status.\n<\/p><\/blockquote>\n<p>For instance, it specifies that SHA-512 is to be used with <code>Ed25519<\/code> and SHAKE256 is to be used with the ML-DSA algorithms.  Note that decisions remain to be made for the SLH-DSA algorithms.<\/p>\n<p>The spec is listed in the set of <a href=\"https:\/\/openid.net\/wg\/connect\/specifications\/\">OpenID Connect Implementer\u2019s Guides<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The OpenID Connect working group has published the initial version of the OpenID Connect Token Hash Algorithm Implementer&#8217;s Guide 1.0. Thanks to Filip Skokan for writing this. Quoting from the Abstract: This OpenID Connect Token Hash Algorithm Implementer&#8217;s Guide 1.0 identifies the hash algorithms to use when calculating OpenID Connect ID Token hash claims, such [&hellip;]<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,27,14,25],"tags":[],"class_list":["post-2889","post","type-post","status-publish","format-standard","hentry","category-claims","category-json","category-openid","category-specifications"],"_links":{"self":[{"href":"https:\/\/self-issued.info\/index.php?rest_route=\/wp\/v2\/posts\/2889","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/self-issued.info\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/self-issued.info\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/self-issued.info\/index.php?rest_route=\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/self-issued.info\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2889"}],"version-history":[{"count":1,"href":"https:\/\/self-issued.info\/index.php?rest_route=\/wp\/v2\/posts\/2889\/revisions"}],"predecessor-version":[{"id":2890,"href":"https:\/\/self-issued.info\/index.php?rest_route=\/wp\/v2\/posts\/2889\/revisions\/2890"}],"wp:attachment":[{"href":"https:\/\/self-issued.info\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2889"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/self-issued.info\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2889"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/self-issued.info\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2889"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}