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<a href="https://gitlab.com/CendioOssman">Pierre Ossman (Work account)</a> created an issue:
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<h2 dir="auto">
<a id="user-content-description-of-problem" class="anchor" href="#description-of-problem" aria-hidden="true"></a>Description of problem:</h2>
<p dir="auto">Current versions of GnuTLS no longer advertise HMAC-SHA256 support unless very explicitly told to do so. This change was introduced in <a href="https://gitlab.com/gnutls/gnutls/commit/62248b6adf0c11d469b04b4bf58aa97deff5a813" data-original="62248b6adf0c11d469b04b4bf58aa97deff5a813" data-link="false" data-link-reference="false" data-project="179611" data-commit="62248b6adf0c11d469b04b4bf58aa97deff5a813" data-reference-type="commit" data-container="body" data-placement="bottom" title="priorities: hmac-sha256 ciphersuites were removed from defaults" class="gfm gfm-commit has-tooltip">62248b6a</a>, but the rationale doesn't match what's actually out there.</p>
<p dir="auto">Two issues:</p>
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<p>Currently still supported versions of Windows has disabled HMAC-SHA1, but never got support for AEAD. This means that GnuTLS cannot connect to the RDP server on Windows 2012 R2.</p>
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<li>
<p>The documentation states that <code>NORMAL</code> (and derived values such as <code>MAC-ALL</code>) should enable all currently secure ciphersuites. This is quite obviously not the case, and very confusing when trying to debug this issue.</p>
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<a id="user-content-version-of-gnutls-used" class="anchor" href="#version-of-gnutls-used" aria-hidden="true"></a>Version of gnutls used:</h2>
<p dir="auto">3.6.8</p>
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<a id="user-content-distributor-of-gnutls-eg-ubuntu-fedora-rhel" class="anchor" href="#distributor-of-gnutls-eg-ubuntu-fedora-rhel" aria-hidden="true"></a>Distributor of gnutls (e.g., Ubuntu, Fedora, RHEL)</h2>
<p dir="auto">Tested on Fedora, but the cause is upstream.</p>
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<a id="user-content-how-reproducible" class="anchor" href="#how-reproducible" aria-hidden="true"></a>How reproducible:</h2>
<p dir="auto">100%</p>
<p dir="auto">Steps to Reproduce:</p>
<pre class="code highlight js-syntax-highlight plaintext" lang="plaintext" v-pre="true"><code><span id="LC1" class="line" lang="plaintext">$ gnutls rds2012r2.example.com -p 3389</span></code></pre>
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<a id="user-content-actual-results" class="anchor" href="#actual-results" aria-hidden="true"></a>Actual results:</h2>
<p dir="auto">Server drops the connection and logs that it could not find a supported ciphersuite.</p>
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<a id="user-content-expected-results" class="anchor" href="#expected-results" aria-hidden="true"></a>Expected results:</h2>
<p dir="auto">TLS handshake succeeds.</p>
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