fix: use SHA256 as default signing algorithm instead of SHA1#104
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OpenSSL 3.x (shipped with Ubuntu 22.04+, Debian 12+) disables SHA1 by default, causing a cryptic "no start line" error when attempting to sign SAML requests with the library defaults. Change the default algorithm from RSA_SHA1 to RSA_SHA256 in KeyHelper::createPrivateKey() and SignatureWriter, so that signing works out of the box on modern systems without requiring the OPENSSL_ENABLE_SHA1_SIGNATURES workaround. Fixes #90
This was referenced Jun 26, 2026
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Summary
RSA_SHA1toRSA_SHA256inKeyHelper::createPrivateKey()SHA1toSHA256inSignatureWriterContext
OpenSSL 3.x (shipped with Ubuntu 22.04+, Debian 12+) disables SHA1 by default. When using the library defaults, signing an
AuthnRequestwould fail with a cryptic error:The workaround found by users was to set
putenv('OPENSSL_ENABLE_SHA1_SIGNATURES=1'), which re-enables the deprecated SHA1 algorithm — a poor security practice.This fix makes SHA256 the default so signing works out of the box on modern systems.
Closes #90