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<a href="https://gitlab.com/dwmw2">David Woodhouse</a> created an issue: <a href="https://gitlab.com/gnutls/gnutls/-/issues/1258">#1258</a>
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<p dir="auto">RFC8446 §4.2.3 says for the RSASSA-PSS algorithms:</p>
<pre class="code highlight js-syntax-highlight language-plaintext" lang="plaintext" v-pre="true"><code><span id="LC1" class="line" lang="plaintext"> The length of the Salt MUST be equal to the length of the output</span>
<span id="LC2" class="line" lang="plaintext"> of the digest algorithm. </span></code></pre>
<p dir="auto">However, in the case of a 1024-bit RSA key using RSA-PSS+SHA512, the maximum possible salt length is only 62 bytes.</p>
<p dir="auto">I originally filed an OpenSSL issue for this <em>not</em> working in OpenSSL: <a href="https://github.com/openssl/openssl/issues/16167" rel="nofollow noreferrer noopener" target="_blank">https://github.com/openssl/openssl/issues/16167</a></p>
<p dir="auto">But now after referring to RFC8446 I think the bug is that it <em>does</em> work in GnuTLS, and it shouldn't.</p>
<p dir="auto">And I should fix my PSS padding code in OpenConnect too, to fail when there isn't enough room for <code>salt_len == hash_len</code> instead of truncating the salt.</p>
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