<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- qmessageauthenticationcode.cpp --> <title>QMessageAuthenticationCode Class | Qt Core 5.12.6</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtcore-index.html">Qt Core</a></td><td ><a href="qtcore-module.html">C++ Classes</a></td><td >QMessageAuthenticationCode</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtcore-index.html">Qt 5.12.6 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"> <div class="toc"> <h3><a name="toc">Contents</a></h3> <ul> <li class="level1"><a href="#public-functions">Public Functions</a></li> <li class="level1"><a href="#static-public-members">Static Public Members</a></li> <li class="level1"><a href="#details">Detailed Description</a></li> </ul> </div> <div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">QMessageAuthenticationCode Class</h1> <!-- $$$QMessageAuthenticationCode-brief --> <p>The <a href="qmessageauthenticationcode.html">QMessageAuthenticationCode</a> class provides a way to generate hash-based message authentication codes. <a href="#details">More...</a></p> <!-- @@@QMessageAuthenticationCode --> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QMessageAuthenticationCode></span> </td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += core</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> Qt 5.1</td></tr></table></div><ul> <li><a href="qmessageauthenticationcode-members.html">List of all members, including inherited members</a></li> </ul> <p><b>Note:</b> All functions in this class are reentrant.</p> <a name="public-functions"></a> <h2 id="public-functions">Public Functions</h2> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qmessageauthenticationcode.html#QMessageAuthenticationCode">QMessageAuthenticationCode</a></b>(QCryptographicHash::Algorithm <i>method</i>, const QByteArray &<i>key</i> = QByteArray())</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qmessageauthenticationcode.html#dtor.QMessageAuthenticationCode">~QMessageAuthenticationCode</a></b>()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qmessageauthenticationcode.html#addData">addData</a></b>(const char *<i>data</i>, int <i>length</i>)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qmessageauthenticationcode.html#addData-1">addData</a></b>(const QByteArray &<i>data</i>)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmessageauthenticationcode.html#addData-2">addData</a></b>(QIODevice *<i>device</i>)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qmessageauthenticationcode.html#reset">reset</a></b>()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QByteArray </td><td class="memItemRight bottomAlign"><b><a href="qmessageauthenticationcode.html#result">result</a></b>() const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qmessageauthenticationcode.html#setKey">setKey</a></b>(const QByteArray &<i>key</i>)</td></tr> </table></div> <a name="static-public-members"></a> <h2 id="static-public-members">Static Public Members</h2> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> QByteArray </td><td class="memItemRight bottomAlign"><b><a href="qmessageauthenticationcode.html#hash">hash</a></b>(const QByteArray &<i>message</i>, const QByteArray &<i>key</i>, QCryptographicHash::Algorithm <i>method</i>)</td></tr> </table></div> <a name="details"></a> <!-- $$$QMessageAuthenticationCode-description --> <div class="descr"> <h2 id="details">Detailed Description</h2> <p>The <a href="qmessageauthenticationcode.html">QMessageAuthenticationCode</a> class provides a way to generate hash-based message authentication codes.</p> <p><a href="qmessageauthenticationcode.html">QMessageAuthenticationCode</a> supports all cryptographic hashes which are supported by <a href="qcryptographichash.html">QCryptographicHash</a>.</p> <p>To generate message authentication code, pass hash algorithm <a href="qcryptographichash.html#Algorithm-enum">QCryptographicHash::Algorithm</a> to constructor, then set key and message by <a href="qmessageauthenticationcode.html#setKey">setKey</a>() and <a href="qmessageauthenticationcode.html#addData">addData</a>() functions. Result can be acquired by <a href="qmessageauthenticationcode.html#result">result</a>() function.</p> <pre class="cpp"> <span class="type"><a href="qbytearray.html">QByteArray</a></span> key <span class="operator">=</span> <span class="string">"key"</span>; <span class="type"><a href="qbytearray.html">QByteArray</a></span> message <span class="operator">=</span> <span class="string">"The quick brown fox jumps over the lazy dog"</span>; ... <span class="type"><a href="qmessageauthenticationcode.html#QMessageAuthenticationCode">QMessageAuthenticationCode</a></span> code(<span class="type"><a href="qcryptographichash.html">QCryptographicHash</a></span><span class="operator">::</span>Sha1); code<span class="operator">.</span>setKey(key); code<span class="operator">.</span>addData(message); code<span class="operator">.</span>result()<span class="operator">.</span>toHex(); <span class="comment">// returns "de7c9b85b8b78aa6bc8a7a36f70a90701c9db4d9"</span> </pre> <p>Alternatively, this effect can be achieved by providing message, key and method to <a href="qmessageauthenticationcode.html#hash">hash</a>() method.</p> <pre class="cpp"> <span class="type"><a href="qmessageauthenticationcode.html#QMessageAuthenticationCode">QMessageAuthenticationCode</a></span><span class="operator">::</span>hash(message<span class="operator">,</span> key<span class="operator">,</span> <span class="type"><a href="qcryptographichash.html">QCryptographicHash</a></span><span class="operator">::</span>Sha1)<span class="operator">.</span>toHex(); </pre> </div> <p><b>See also </b><a href="qcryptographichash.html">QCryptographicHash</a>.</p> <!-- @@@QMessageAuthenticationCode --> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$QMessageAuthenticationCode[overload1]$$$QMessageAuthenticationCodeQCryptographicHash::AlgorithmconstQByteArray& --> <h3 class="fn" id="QMessageAuthenticationCode"><a name="QMessageAuthenticationCode"></a>QMessageAuthenticationCode::<span class="name">QMessageAuthenticationCode</span>(<span class="type"><a href="qcryptographichash.html#Algorithm-enum">QCryptographicHash::Algorithm</a></span> <i>method</i>, const <span class="type"><a href="qbytearray.html">QByteArray</a></span> &<i>key</i> = QByteArray())</h3> <p>Constructs an object that can be used to create a cryptographic hash from data using method <i>method</i> and key <i>key</i>.</p> <!-- @@@QMessageAuthenticationCode --> <!-- $$$~QMessageAuthenticationCode[overload1]$$$~QMessageAuthenticationCode --> <h3 class="fn" id="dtor.QMessageAuthenticationCode"><a name="dtor.QMessageAuthenticationCode"></a>QMessageAuthenticationCode::<span class="name">~QMessageAuthenticationCode</span>()</h3> <p>Destroys the object.</p> <!-- @@@~QMessageAuthenticationCode --> <!-- $$$addData[overload1]$$$addDataconstchar*int --> <h3 class="fn" id="addData"><a name="addData"></a><span class="type">void</span> QMessageAuthenticationCode::<span class="name">addData</span>(const <span class="type">char</span> *<i>data</i>, <span class="type">int</span> <i>length</i>)</h3> <p>Adds the first <i>length</i> chars of <i>data</i> to the message.</p> <!-- @@@addData --> <!-- $$$addData$$$addDataconstQByteArray& --> <h3 class="fn" id="addData-1"><a name="addData-1"></a><span class="type">void</span> QMessageAuthenticationCode::<span class="name">addData</span>(const <span class="type"><a href="qbytearray.html">QByteArray</a></span> &<i>data</i>)</h3> <p>This function overloads <a href="qmessageauthenticationcode.html#addData">addData</a>().</p> <!-- @@@addData --> <!-- $$$addData$$$addDataQIODevice* --> <h3 class="fn" id="addData-2"><a name="addData-2"></a><span class="type">bool</span> QMessageAuthenticationCode::<span class="name">addData</span>(<span class="type"><a href="qiodevice.html">QIODevice</a></span> *<i>device</i>)</h3> <p>Reads the data from the open <a href="qiodevice.html">QIODevice</a> <i>device</i> until it ends and adds it to message. Returns <code>true</code> if reading was successful.</p> <p><b>Note: </b><i>device</i> must be already opened.</p><!-- @@@addData --> <!-- $$$hash[overload1]$$$hashconstQByteArray&constQByteArray&QCryptographicHash::Algorithm --> <h3 class="fn" id="hash"><a name="hash"></a><code>[static] </code><span class="type"><a href="qbytearray.html">QByteArray</a></span> QMessageAuthenticationCode::<span class="name">hash</span>(const <span class="type"><a href="qbytearray.html">QByteArray</a></span> &<i>message</i>, const <span class="type"><a href="qbytearray.html">QByteArray</a></span> &<i>key</i>, <span class="type"><a href="qcryptographichash.html#Algorithm-enum">QCryptographicHash::Algorithm</a></span> <i>method</i>)</h3> <p>Returns the authentication code for the message <i>message</i> using the key <i>key</i> and the method <i>method</i>.</p> <!-- @@@hash --> <!-- $$$reset[overload1]$$$reset --> <h3 class="fn" id="reset"><a name="reset"></a><span class="type">void</span> QMessageAuthenticationCode::<span class="name">reset</span>()</h3> <p>Resets message data. Calling this method doesn't affect the key.</p> <!-- @@@reset --> <!-- $$$result[overload1]$$$result --> <h3 class="fn" id="result"><a name="result"></a><span class="type"><a href="qbytearray.html">QByteArray</a></span> QMessageAuthenticationCode::<span class="name">result</span>() const</h3> <p>Returns the final authentication code.</p> <p><b>See also </b><a href="qbytearray.html#toHex">QByteArray::toHex</a>().</p> <!-- @@@result --> <!-- $$$setKey[overload1]$$$setKeyconstQByteArray& --> <h3 class="fn" id="setKey"><a name="setKey"></a><span class="type">void</span> QMessageAuthenticationCode::<span class="name">setKey</span>(const <span class="type"><a href="qbytearray.html">QByteArray</a></span> &<i>key</i>)</h3> <p>Sets secret <i>key</i>. Calling this method automatically resets the object state.</p> <!-- @@@setKey --> </div> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>