<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/> <title>Wt: Wt::Auth::BCryptHashFunction Class Reference</title> <link href="tabs.css" rel="stylesheet" type="text/css"/> <link href="doxygen.css" rel="stylesheet" type="text/css" /> <link href="search/search.css" rel="stylesheet" type="text/css"/> <script type="text/javascript" src="jquery.js"></script> <script type="text/javascript" src="search/search.js"></script> <script type="text/javascript"> $(document).ready(function() { searchBox.OnSelectItem(0); }); </script> </head> <body> <div id="top"><!-- do not remove this div! --> <div id="titlearea"> <table cellspacing="0" cellpadding="0"> <tbody> <tr style="height: 56px;"> <td style="padding-left: 0.5em;"> <div id="projectname">Wt  <span id="projectnumber">3.2.3</span> </div> </td> </tr> </tbody> </table> </div> <!-- Generated by Doxygen 1.7.5.1 --> <script type="text/javascript"> var searchBox = new SearchBox("searchBox", "search",false,'Search'); </script> <div id="navrow1" class="tabs"> <ul class="tablist"> <li><a href="index.html"><span>Main Page</span></a></li> <li><a href="pages.html"><span>Related Pages</span></a></li> <li><a href="modules.html"><span>Modules</span></a></li> <li><a href="namespaces.html"><span>Namespaces</span></a></li> <li class="current"><a href="annotated.html"><span>Classes</span></a></li> <li><a href="files.html"><span>Files</span></a></li> <li> <div id="MSearchBox" class="MSearchBoxInactive"> <span class="left"> <img id="MSearchSelect" src="search/mag_sel.png" onmouseover="return searchBox.OnSearchSelectShow()" onmouseout="return searchBox.OnSearchSelectHide()" alt=""/> <input type="text" id="MSearchField" value="Search" accesskey="S" onfocus="searchBox.OnSearchFieldFocus(true)" onblur="searchBox.OnSearchFieldFocus(false)" onkeyup="searchBox.OnSearchFieldChange(event)"/> </span><span class="right"> <a id="MSearchClose" href="javascript:searchBox.CloseResultsWindow()"><img id="MSearchCloseImg" border="0" src="search/close.png" alt=""/></a> </span> </div> </li> </ul> </div> <div id="navrow2" class="tabs2"> <ul class="tablist"> <li><a href="annotated.html"><span>Class List</span></a></li> <li><a href="inherits.html"><span>Class Hierarchy</span></a></li> <li><a href="functions.html"><span>Class Members</span></a></li> </ul> </div> <div id="nav-path" class="navpath"> <ul> <li class="navelem"><a class="el" href="namespaceWt.html">Wt</a> </li> <li class="navelem"><a class="el" href="namespaceWt_1_1Auth.html">Auth</a> </li> <li class="navelem"><a class="el" href="classWt_1_1Auth_1_1BCryptHashFunction.html">BCryptHashFunction</a> </li> </ul> </div> </div> <div class="header"> <div class="summary"> <a href="#pub-methods">Public Member Functions</a> </div> <div class="headertitle"> <div class="title">Wt::Auth::BCryptHashFunction Class Reference<div class="ingroups"><a class="el" href="group__auth.html">Authentication module (Wt::Auth)</a></div></div> </div> </div> <div class="contents"> <!-- doxytag: class="Wt::Auth::BCryptHashFunction" --><!-- doxytag: inherits="Wt::Auth::HashFunction" --> <p>An cryptographic hash function that implements bcrypt. <a href="classWt_1_1Auth_1_1BCryptHashFunction.html#details">More...</a></p> <p><code>#include <Wt/Auth/HashFunction></code></p> <div class="dynheader"> Inheritance diagram for Wt::Auth::BCryptHashFunction:</div> <div class="dyncontent"> <div class="center"><img src="classWt_1_1Auth_1_1BCryptHashFunction__inherit__graph.png" border="0" usemap="#Wt_1_1Auth_1_1BCryptHashFunction_inherit__map" alt="Inheritance graph"/></div> <map name="Wt_1_1Auth_1_1BCryptHashFunction_inherit__map" id="Wt_1_1Auth_1_1BCryptHashFunction_inherit__map"> <area shape="rect" href="classWt_1_1Auth_1_1HashFunction.html" title="An abstract cryptographic hash function interface." alt="" coords="25,5,185,32"/></map> <center><span class="legend">[<a href="graph_legend.html">legend</a>]</span></center></div> <p><a href="classWt_1_1Auth_1_1BCryptHashFunction-members.html">List of all members.</a></p> <table class="memberdecls"> <tr><td colspan="2"><h2><a name="pub-methods"></a> Public Member Functions</h2></td></tr> <tr><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="classWt_1_1Auth_1_1BCryptHashFunction.html#aefb9597277b162b10c0b61e9b5e0114f">BCryptHashFunction</a> (int count=0)</td></tr> <tr><td class="mdescLeft"> </td><td class="mdescRight">Constructor. <a href="#aefb9597277b162b10c0b61e9b5e0114f"></a><br/></td></tr> <tr><td class="memItemLeft" align="right" valign="top">virtual std::string </td><td class="memItemRight" valign="bottom"><a class="el" href="classWt_1_1Auth_1_1BCryptHashFunction.html#a50497e9ac2c50477a6374006a153a9cf">name</a> () const </td></tr> <tr><td class="mdescLeft"> </td><td class="mdescRight">Returns the name for this hash function. <a href="#a50497e9ac2c50477a6374006a153a9cf"></a><br/></td></tr> <tr><td class="memItemLeft" align="right" valign="top">virtual std::string </td><td class="memItemRight" valign="bottom"><a class="el" href="classWt_1_1Auth_1_1BCryptHashFunction.html#a5df3892cc0472122243d8e9a83e4cebc">compute</a> (const std::string &msg, const std::string &salt) const </td></tr> <tr><td class="mdescLeft"> </td><td class="mdescRight">Computes the hash of a message + salt. <a href="#a5df3892cc0472122243d8e9a83e4cebc"></a><br/></td></tr> <tr><td class="memItemLeft" align="right" valign="top">virtual bool </td><td class="memItemRight" valign="bottom"><a class="el" href="classWt_1_1Auth_1_1BCryptHashFunction.html#a201bf34057eb6f4e3cd9dd72b1702cc4">verify</a> (const std::string &msg, const std::string &hash, const std::string &salt) const </td></tr> <tr><td class="mdescLeft"> </td><td class="mdescRight">Verifies a message with the salted hash. <a href="#a201bf34057eb6f4e3cd9dd72b1702cc4"></a><br/></td></tr> </table> <hr/><a name="details" id="details"></a><h2>Detailed Description</h2> <div class="textblock"><p>An cryptographic hash function that implements bcrypt. </p> <p>This hashing function is intended for password hashes. In addition to be collision-resistant, the bcrypt algorithm has a parameter which makes the computation more computationally intensive. In this way, a dictionary-based attack on a compromised hash is also less feasible. </p> </div><hr/><h2>Constructor & Destructor Documentation</h2> <a class="anchor" id="aefb9597277b162b10c0b61e9b5e0114f"></a><!-- doxytag: member="Wt::Auth::BCryptHashFunction::BCryptHashFunction" ref="aefb9597277b162b10c0b61e9b5e0114f" args="(int count=0)" --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">Wt::Auth::BCryptHashFunction::BCryptHashFunction </td> <td>(</td> <td class="paramtype">int </td> <td class="paramname"><em>count</em> = <code>0</code></td><td>)</td> <td></td> </tr> </table> </div> <div class="memdoc"> <p>Constructor. </p> <p>The <code>count</code> parameter controls the number of iterations, and thus the computational complexity. With a value of 0, a small default is chosen. The computational complexity increases exponentionally with increasing values f <code>count</code>. The parameter only affects new hashes computed with <a class="el" href="classWt_1_1Auth_1_1BCryptHashFunction.html#a5df3892cc0472122243d8e9a83e4cebc" title="Computes the hash of a message + salt.">compute()</a>, and its value is stored in the computed hash.</p> <p>The value of <code>count</code> needs to be 0, or in the range 4-31. </p> </div> </div> <hr/><h2>Member Function Documentation</h2> <a class="anchor" id="a5df3892cc0472122243d8e9a83e4cebc"></a><!-- doxytag: member="Wt::Auth::BCryptHashFunction::compute" ref="a5df3892cc0472122243d8e9a83e4cebc" args="(const std::string &msg, const std::string &salt) const " --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">std::string Wt::Auth::BCryptHashFunction::compute </td> <td>(</td> <td class="paramtype">const std::string & </td> <td class="paramname"><em>msg</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const std::string & </td> <td class="paramname"><em>salt</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td> const<code> [virtual]</code></td> </tr> </table> </div> <div class="memdoc"> <p>Computes the hash of a message + salt. </p> <p>The message is usually an ASCII or UTF-8 string.</p> <p>The <code>salt</code> and the computed hash are encoded in printable characters. This is usually ASCII-encoded(as for the UNIX crypt() functions)or could be Base64-encoded. </p> <p>Implements <a class="el" href="classWt_1_1Auth_1_1HashFunction.html#a7a79f2aae54b390ba8a3b451d590ac92">Wt::Auth::HashFunction</a>.</p> </div> </div> <a class="anchor" id="a50497e9ac2c50477a6374006a153a9cf"></a><!-- doxytag: member="Wt::Auth::BCryptHashFunction::name" ref="a50497e9ac2c50477a6374006a153a9cf" args="() const " --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">std::string Wt::Auth::BCryptHashFunction::name </td> <td>(</td> <td class="paramname"></td><td>)</td> <td> const<code> [virtual]</code></td> </tr> </table> </div> <div class="memdoc"> <p>Returns the name for this hash function. </p> <p>Returns <code>"bcrypt"</code>. </p> <p>Implements <a class="el" href="classWt_1_1Auth_1_1HashFunction.html#aaa3f4d60d558577c118c3d8684f72ed4">Wt::Auth::HashFunction</a>.</p> </div> </div> <a class="anchor" id="a201bf34057eb6f4e3cd9dd72b1702cc4"></a><!-- doxytag: member="Wt::Auth::BCryptHashFunction::verify" ref="a201bf34057eb6f4e3cd9dd72b1702cc4" args="(const std::string &msg, const std::string &hash, const std::string &salt) const " --> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">bool Wt::Auth::BCryptHashFunction::verify </td> <td>(</td> <td class="paramtype">const std::string & </td> <td class="paramname"><em>msg</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const std::string & </td> <td class="paramname"><em>salt</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const std::string & </td> <td class="paramname"><em>hash</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td> const<code> [virtual]</code></td> </tr> </table> </div> <div class="memdoc"> <p>Verifies a message with the salted hash. </p> <p>The base implementation will recompute the hash of the message with the given salt, and compare it to the <code>hash</code>.</p> <p>Some methods however store the salt and additional settings in the <code>hash</code>, and this information is thus needed to verify the message hash. </p> <p>Reimplemented from <a class="el" href="classWt_1_1Auth_1_1HashFunction.html#a4599fe0518fb61e33f5bf192531d7585">Wt::Auth::HashFunction</a>.</p> </div> </div> </div> <!-- window showing the filter options --> <div id="MSearchSelectWindow" onmouseover="return searchBox.OnSearchSelectShow()" onmouseout="return searchBox.OnSearchSelectHide()" onkeydown="return searchBox.OnSearchSelectKey(event)"> <a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(0)"><span class="SelectionMark"> </span>All</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(1)"><span class="SelectionMark"> </span>Classes</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(2)"><span class="SelectionMark"> </span>Namespaces</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(3)"><span class="SelectionMark"> </span>Files</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(4)"><span class="SelectionMark"> </span>Functions</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(5)"><span class="SelectionMark"> </span>Variables</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(6)"><span class="SelectionMark"> </span>Typedefs</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(7)"><span class="SelectionMark"> </span>Enumerations</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(8)"><span class="SelectionMark"> </span>Enumerator</a></div> <!-- iframe showing the search results (closed by default) --> <div id="MSearchResultsWindow"> <iframe src="javascript:void(0)" frameborder="0" name="MSearchResults" id="MSearchResults"> </iframe> </div> <hr size="1"><address style="text-align: right; margin: 3px"><small> Generated on Thu Nov 1 2012 for <a href="http://www.webtoolkit.eu/wt">the C++ Web Toolkit (Wt)</a> by <a href="http://www.doxygen.org/index.html"><img src="doxygen.png" alt="doxygen" border="0" style="vertical-align: middle; display: inline-block; height: 2em"></a> 1.7.5.1</small></address> </body> </html>