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<h1 class="refname">openssl_verify</h1>
<p class="verinfo">(PHP 4 >= 4.0.4, PHP 5)</p><p class="refpurpose"><span class="refname">openssl_verify</span> — <span class="dc-title">Verify signature</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.openssl-verify-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">int</span> <span class="methodname"><strong>openssl_verify</strong></span>
( <span class="methodparam"><span class="type">string</span> <code class="parameter">$data</code></span>
, <span class="methodparam"><span class="type">string</span> <code class="parameter">$signature</code></span>
, <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <code class="parameter">$pub_key_id</code></span>
[, <span class="methodparam"><span class="type">int</span> <code class="parameter">$signature_alg</code><span class="initializer"> = OPENSSL_ALGO_SHA1</span></span>
] )</div>
<p class="para rdfs-comment">
<span class="function"><strong>openssl_verify()</strong></span> verifies that the
<em><code class="parameter">signature</code></em> is correct for the specified
<em><code class="parameter">data</code></em> using the public key associated with
<em><code class="parameter">pub_key_id</code></em>. This must be the public key
corresponding to the private key used for signing.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.openssl-verify-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">data</code></em></span>
<dd>
<p class="para">
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">signature</code></em></span>
<dd>
<p class="para">
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">pub_key_id</code></em></span>
<dd>
<p class="para">
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">signature_alg</code></em></span>
<dd>
<p class="para">
For more information see the list of <a href="openssl.signature-algos.html" class="link">Signature Algorithms</a>.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.openssl-verify-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns 1 if the signature is correct, 0 if it is incorrect, and
-1 on error.
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.openssl-verify-changelog">
<h3 class="title">Changelog</h3>
<p class="para">
<table class="doctable informaltable">
<thead>
<tr>
<th>Version</th>
<th>Description</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td>5.2.0</td>
<td>
The <em><code class="parameter">signature_alg</code></em> parameter was added.
</td>
</tr>
</tbody>
</table>
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.openssl-verify-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-871">
<p><strong>Example #1 <span class="function"><strong>openssl_verify()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// $data and $signature are assumed to contain the data and the signature<br /><br />// fetch public key from certificate and ready it<br /></span><span style="color: #0000BB">$fp </span><span style="color: #007700">= </span><span style="color: #0000BB">fopen</span><span style="color: #007700">(</span><span style="color: #DD0000">"/src/openssl-0.9.6/demos/sign/cert.pem"</span><span style="color: #007700">, </span><span style="color: #DD0000">"r"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$cert </span><span style="color: #007700">= </span><span style="color: #0000BB">fread</span><span style="color: #007700">(</span><span style="color: #0000BB">$fp</span><span style="color: #007700">, </span><span style="color: #0000BB">8192</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">fclose</span><span style="color: #007700">(</span><span style="color: #0000BB">$fp</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$pubkeyid </span><span style="color: #007700">= </span><span style="color: #0000BB">openssl_get_publickey</span><span style="color: #007700">(</span><span style="color: #0000BB">$cert</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// state whether signature is okay or not<br /></span><span style="color: #0000BB">$ok </span><span style="color: #007700">= </span><span style="color: #0000BB">openssl_verify</span><span style="color: #007700">(</span><span style="color: #0000BB">$data</span><span style="color: #007700">, </span><span style="color: #0000BB">$signature</span><span style="color: #007700">, </span><span style="color: #0000BB">$pubkeyid</span><span style="color: #007700">);<br />if (</span><span style="color: #0000BB">$ok </span><span style="color: #007700">== </span><span style="color: #0000BB">1</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"good"</span><span style="color: #007700">;<br />} elseif (</span><span style="color: #0000BB">$ok </span><span style="color: #007700">== </span><span style="color: #0000BB">0</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"bad"</span><span style="color: #007700">;<br />} else {<br /> echo </span><span style="color: #DD0000">"ugly, error checking signature"</span><span style="color: #007700">;<br />}<br /></span><span style="color: #FF8000">// free the key from memory<br /></span><span style="color: #0000BB">openssl_free_key</span><span style="color: #007700">(</span><span style="color: #0000BB">$pubkeyid</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</p>
</div>
<div class="refsect1 seealso" id="refsect1-function.openssl-verify-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.openssl-sign.html" class="function" rel="rdfs-seeAlso">openssl_sign()</a> - Generate signature</span></li>
</ul>
</p>
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