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<title>GnuTLS 3.5.4: Verifying a certificate using DANE</title>
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<a name="Verifying-a-certificate-using-DANE"></a>
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Previous: <a href="Verifying-a-certificate-using-trust-on-first-use-authentication.html#Verifying-a-certificate-using-trust-on-first-use-authentication" accesskey="p" rel="prev">Verifying a certificate using trust on first use authentication</a>, Up: <a href="Advanced-certificate-verification.html#Advanced-certificate-verification" accesskey="u" rel="up">Advanced certificate verification</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Function-and-Data-Index.html#Function-and-Data-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
<a name="Verifying-a-certificate-using-DANE-_0028DNSSEC_0029"></a>
<h4 class="subsubsection">4.1.3.2 Verifying a certificate using DANE (DNSSEC)</h4>
<a name="index-verifying-certificate-paths-3"></a>
<a name="index-DANE"></a>
<a name="index-DNSSEC"></a>
<p>The DANE protocol is a protocol that can be used to verify TLS certificates
using the DNS (or better DNSSEC) protocols. The DNS security extensions (DNSSEC)
provide an alternative public key infrastructure to the commercial CAs that
are typically used to sign TLS certificates. The DANE protocol takes advantage
of the DNSSEC infrastructure to verify TLS certificates. This can be
in addition to the verification by CA infrastructure or
may even replace it where DNSSEC is fully deployed. Note however, that DNSSEC deployment is
fairly new and it would be better to use it as an additional verification
method rather than the only one.
</p>
<p>The DANE functionality is provided by the <code>libgnutls-dane</code> library that is shipped
with GnuTLS and the function prototypes are in <code>gnutls/dane.h</code>.
See <a href="Certificate-verification.html#Certificate-verification">Certificate verification</a> for information on how to use the library.
</p>
<p>Note however, that the DANE RFC mandates the verification methods
one should use in addition to the validation via DNSSEC TLSA entries.
GnuTLS doesn’t follow that RFC requirement, and the term DANE verification
in this manual refers to the TLSA entry verification. In GnuTLS any
other verification methods can be used (e.g., PKIX or TOFU) on top of
DANE.
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