<!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"/> <meta http-equiv="X-UA-Compatible" content="IE=9"/> <meta name="generator" content="Doxygen 1.8.14"/> <meta name="viewport" content="width=device-width, initial-scale=1"/> <title>Crypto++: scrypt.h Source File</title> <link href="tabs.css" rel="stylesheet" type="text/css"/> <script type="text/javascript" src="jquery.js"></script> <script type="text/javascript" src="dynsections.js"></script> <link href="doxygen.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="top"><!-- do not remove this div, it is closed by doxygen! --> <div id="titlearea"> <table cellspacing="0" cellpadding="0"> <tbody> <tr style="height: 56px;"> <td id="projectalign" style="padding-left: 0.5em;"> <div id="projectname">Crypto++  <span id="projectnumber">7.0</span> </div> <div id="projectbrief">Free C++ class library of cryptographic schemes</div> </td> </tr> </tbody> </table> </div> <!-- end header part --> <!-- Generated by Doxygen 1.8.14 --> <script type="text/javascript" src="menudata.js"></script> <script type="text/javascript" src="menu.js"></script> <script type="text/javascript"> /* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */ $(function() { initMenu('',false,false,'search.php','Search'); }); /* @license-end */</script> <div id="main-nav"></div> </div><!-- top --> <div class="header"> <div class="headertitle"> <div class="title">scrypt.h</div> </div> </div><!--header--> <div class="contents"> <a href="scrypt_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">// scrypt.h - written and placed in public domain by Jeffrey Walton.</span></div><div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment">// Based on reference source code by Colin Percival.</span></div><div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment"></span></div><div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment">/// \file scrypt.h</span></div><div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment">/// \brief Classes for Scrypt from RFC 7914</span></div><div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment">/// \sa <A HREF="https://www.tarsnap.com/scrypt/scrypt.pdf">Stronger Key Derivation via</span></div><div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment">/// Sequential Memory-Hard Functions</a>,</span></div><div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment">/// <A HREF="https://www.tarsnap.com/scrypt.html">The scrypt key derivation function</A></span></div><div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment">/// and <A HREF="https://tools.ietf.org/html/rfc7914">RFC 7914, The scrypt Password-Based</span></div><div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="comment">/// Key Derivation Function</A></span></div><div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="comment">/// \since Crypto++ 6.2</span></div><div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="comment"></span></div><div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="preprocessor">#ifndef CRYPTOPP_SCRYPT_H</span></div><div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="preprocessor">#define CRYPTOPP_SCRYPT_H</span></div><div class="line"><a name="l00015"></a><span class="lineno"> 15</span> </div><div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="preprocessor">#include "<a class="code" href="cryptlib_8h.html">cryptlib.h</a>"</span></div><div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="preprocessor">#include "<a class="code" href="secblock_8h.html">secblock.h</a>"</span></div><div class="line"><a name="l00018"></a><span class="lineno"> 18</span> </div><div class="line"><a name="l00019"></a><span class="lineno"> 19</span> NAMESPACE_BEGIN(<a class="code" href="namespace_crypto_p_p.html">CryptoPP</a>)</div><div class="line"><a name="l00020"></a><span class="lineno"> 20</span> </div><div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="comment">/// \brief Scrypt key derivation function</span></div><div class="line"><a name="l00022"></a><span class="lineno"> 22</span> <span class="comment"></span><span class="comment">/// \details The Crypto++ implementation uses OpenMP to accelerate the derivation when</span></div><div class="line"><a name="l00023"></a><span class="lineno"> 23</span> <span class="comment"></span><span class="comment">/// available.</span></div><div class="line"><a name="l00024"></a><span class="lineno"> 24</span> <span class="comment"></span><span class="comment">/// \details The Crypto++ implementation of Scrypt is limited by C++ datatypes. For</span></div><div class="line"><a name="l00025"></a><span class="lineno"> 25</span> <span class="comment"></span><span class="comment">/// example, the library is limited to a derived key length of <tt>SIZE_MAX</tt>,</span></div><div class="line"><a name="l00026"></a><span class="lineno"> 26</span> <span class="comment"></span><span class="comment">/// and not <tt>(2^32 - 1) * 32</tt>.</span></div><div class="line"><a name="l00027"></a><span class="lineno"> 27</span> <span class="comment"></span><span class="comment">/// \sa <A HREF="https://www.tarsnap.com/scrypt/scrypt.pdf">Stronger Key Derivation via</span></div><div class="line"><a name="l00028"></a><span class="lineno"> 28</span> <span class="comment"></span><span class="comment">/// Sequential Memory-Hard Functions</a>,</span></div><div class="line"><a name="l00029"></a><span class="lineno"> 29</span> <span class="comment"></span><span class="comment">/// <A HREF="https://www.tarsnap.com/scrypt.html">The scrypt key derivation function</A></span></div><div class="line"><a name="l00030"></a><span class="lineno"> 30</span> <span class="comment"></span><span class="comment">/// and <A HREF="https://tools.ietf.org/html/rfc7914">RFC 7914, The scrypt Password-Based</span></div><div class="line"><a name="l00031"></a><span class="lineno"> 31</span> <span class="comment"></span><span class="comment">/// Key Derivation Function</A></span></div><div class="line"><a name="l00032"></a><span class="lineno"> 32</span> <span class="comment"></span><span class="comment">/// \since Crypto++ 6.2</span></div><div class="line"><a name="l00033"></a><span class="lineno"><a class="line" href="class_scrypt.html"> 33</a></span> <span class="comment"></span>class <a class="code" href="class_scrypt.html">Scrypt</a> : public <a class="code" href="class_key_derivation_function.html">KeyDerivationFunction</a></div><div class="line"><a name="l00034"></a><span class="lineno"> 34</span> {</div><div class="line"><a name="l00035"></a><span class="lineno"> 35</span> <span class="keyword">public</span>:</div><div class="line"><a name="l00036"></a><span class="lineno"> 36</span>  <span class="keyword">virtual</span> ~<a class="code" href="class_scrypt.html">Scrypt</a>() {}</div><div class="line"><a name="l00037"></a><span class="lineno"> 37</span> </div><div class="line"><a name="l00038"></a><span class="lineno"> 38</span>  <span class="keyword">static</span> std::string StaticAlgorithmName () {</div><div class="line"><a name="l00039"></a><span class="lineno"> 39</span>  <span class="keywordflow">return</span> <span class="stringliteral">"scrypt"</span>;</div><div class="line"><a name="l00040"></a><span class="lineno"> 40</span>  }</div><div class="line"><a name="l00041"></a><span class="lineno"> 41</span> </div><div class="line"><a name="l00042"></a><span class="lineno"> 42</span>  <span class="comment">// KeyDerivationFunction interface</span></div><div class="line"><a name="l00043"></a><span class="lineno"><a class="line" href="class_scrypt.html#a102cc305016c030ad04a9ca3fa80bee2"> 43</a></span>  std::string <a class="code" href="class_scrypt.html#a102cc305016c030ad04a9ca3fa80bee2">AlgorithmName</a>()<span class="keyword"> const </span>{</div><div class="line"><a name="l00044"></a><span class="lineno"> 44</span>  <span class="keywordflow">return</span> StaticAlgorithmName();</div><div class="line"><a name="l00045"></a><span class="lineno"> 45</span>  }</div><div class="line"><a name="l00046"></a><span class="lineno"> 46</span> </div><div class="line"><a name="l00047"></a><span class="lineno"> 47</span>  <span class="comment">// KeyDerivationFunction interface</span></div><div class="line"><a name="l00048"></a><span class="lineno"><a class="line" href="class_scrypt.html#ab3b23597d8bcb9af8d55bc8aa57bf709"> 48</a></span>  <span class="keywordtype">size_t</span> <a class="code" href="class_scrypt.html#ab3b23597d8bcb9af8d55bc8aa57bf709">MaxDerivedLength</a>()<span class="keyword"> const </span>{</div><div class="line"><a name="l00049"></a><span class="lineno"> 49</span>  <span class="keywordflow">return</span> <span class="keyword">static_cast<</span><span class="keywordtype">size_t</span><span class="keyword">></span>(-1);</div><div class="line"><a name="l00050"></a><span class="lineno"> 50</span>  }</div><div class="line"><a name="l00051"></a><span class="lineno"> 51</span> </div><div class="line"><a name="l00052"></a><span class="lineno"> 52</span>  <span class="comment">// KeyDerivationFunction interface</span></div><div class="line"><a name="l00053"></a><span class="lineno"> 53</span>  <span class="keywordtype">size_t</span> GetValidDerivedLength(<span class="keywordtype">size_t</span> keylength) <span class="keyword">const</span>;</div><div class="line"><a name="l00054"></a><span class="lineno"> 54</span> </div><div class="line"><a name="l00055"></a><span class="lineno"> 55</span>  <span class="comment">// KeyDerivationFunction interface</span></div><div class="line"><a name="l00056"></a><span class="lineno"> 56</span>  <span class="keywordtype">size_t</span> DeriveKey(byte *derived, <span class="keywordtype">size_t</span> derivedLen, <span class="keyword">const</span> byte *secret, <span class="keywordtype">size_t</span> secretLen,</div><div class="line"><a name="l00057"></a><span class="lineno"> 57</span>  <span class="keyword">const</span> <a class="code" href="class_name_value_pairs.html">NameValuePairs</a>& params) <span class="keyword">const</span>;</div><div class="line"><a name="l00058"></a><span class="lineno"> 58</span> <span class="comment"></span></div><div class="line"><a name="l00059"></a><span class="lineno"> 59</span> <span class="comment"> /// \brief Derive a key from a seed</span></div><div class="line"><a name="l00060"></a><span class="lineno"> 60</span> <span class="comment"> /// \param derived the derived output buffer</span></div><div class="line"><a name="l00061"></a><span class="lineno"> 61</span> <span class="comment"> /// \param derivedLen the size of the derived buffer, in bytes</span></div><div class="line"><a name="l00062"></a><span class="lineno"> 62</span> <span class="comment"> /// \param secret the seed input buffer</span></div><div class="line"><a name="l00063"></a><span class="lineno"> 63</span> <span class="comment"> /// \param secretLen the size of the secret buffer, in bytes</span></div><div class="line"><a name="l00064"></a><span class="lineno"> 64</span> <span class="comment"> /// \param salt the salt input buffer</span></div><div class="line"><a name="l00065"></a><span class="lineno"> 65</span> <span class="comment"> /// \param saltLen the size of the salt buffer, in bytes</span></div><div class="line"><a name="l00066"></a><span class="lineno"> 66</span> <span class="comment"> /// \param cost the CPU/memory cost factor</span></div><div class="line"><a name="l00067"></a><span class="lineno"> 67</span> <span class="comment"> /// \param blockSize the block size</span></div><div class="line"><a name="l00068"></a><span class="lineno"> 68</span> <span class="comment"> /// \param parallelization the parallelization factor</span></div><div class="line"><a name="l00069"></a><span class="lineno"> 69</span> <span class="comment"> /// \returns the number of iterations performed</span></div><div class="line"><a name="l00070"></a><span class="lineno"> 70</span> <span class="comment"> /// \throws InvalidDerivedLength if <tt>derivedLen</tt> is invalid for the scheme</span></div><div class="line"><a name="l00071"></a><span class="lineno"> 71</span> <span class="comment"> /// \details DeriveKey() provides a standard interface to derive a key from</span></div><div class="line"><a name="l00072"></a><span class="lineno"> 72</span> <span class="comment"> /// a seed and other parameters. Each class that derives from KeyDerivationFunction</span></div><div class="line"><a name="l00073"></a><span class="lineno"> 73</span> <span class="comment"> /// provides an overload that accepts most parameters used by the derivation function.</span></div><div class="line"><a name="l00074"></a><span class="lineno"> 74</span> <span class="comment"> /// \details The CPU/Memory <tt>cost</tt> parameter ("N" in the documents) must be</span></div><div class="line"><a name="l00075"></a><span class="lineno"> 75</span> <span class="comment"> /// larger than 1, a power of 2, and less than <tt>2^(128 * r / 8)</tt>.</span></div><div class="line"><a name="l00076"></a><span class="lineno"> 76</span> <span class="comment"> /// \details The parameter <tt>blockSize</tt> ("r" in the documents) specifies the block</span></div><div class="line"><a name="l00077"></a><span class="lineno"> 77</span> <span class="comment"> /// size.</span></div><div class="line"><a name="l00078"></a><span class="lineno"> 78</span> <span class="comment"> /// \details The <tt>parallelization</tt> parameter ("p" in the documents) is a positive</span></div><div class="line"><a name="l00079"></a><span class="lineno"> 79</span> <span class="comment"> /// integer less than or equal to <tt>((2^32-1) * 32) / (128 * r)</tt>.</span></div><div class="line"><a name="l00080"></a><span class="lineno"> 80</span> <span class="comment"> /// \details Scrypt always returns 1 because it only performs 1 iteration. Other</span></div><div class="line"><a name="l00081"></a><span class="lineno"> 81</span> <span class="comment"> /// derivation functions, like PBKDF's, will return more interesting values.</span></div><div class="line"><a name="l00082"></a><span class="lineno"> 82</span> <span class="comment"> /// \details The Crypto++ implementation of Scrypt is limited by C++ datatypes. For</span></div><div class="line"><a name="l00083"></a><span class="lineno"> 83</span> <span class="comment"> /// example, the library is limited to a derived key length of <tt>SIZE_MAX</tt>,</span></div><div class="line"><a name="l00084"></a><span class="lineno"> 84</span> <span class="comment"> /// and not <tt>(2^32 - 1) * 32</tt>.</span></div><div class="line"><a name="l00085"></a><span class="lineno"> 85</span> <span class="comment"></span> <span class="keywordtype">size_t</span> DeriveKey(byte *derived, <span class="keywordtype">size_t</span> derivedLen, <span class="keyword">const</span> byte *secret, <span class="keywordtype">size_t</span> secretLen,</div><div class="line"><a name="l00086"></a><span class="lineno"> 86</span>  <span class="keyword">const</span> byte *salt, <span class="keywordtype">size_t</span> saltLen, word64 cost=2, word64 blockSize=8, word64 parallelization=1) <span class="keyword">const</span>;</div><div class="line"><a name="l00087"></a><span class="lineno"> 87</span> </div><div class="line"><a name="l00088"></a><span class="lineno"> 88</span> <span class="keyword">protected</span>:</div><div class="line"><a name="l00089"></a><span class="lineno"> 89</span>  <span class="keyword">enum</span> {defaultCost=2, defaultBlockSize=8, defaultParallelization=1};</div><div class="line"><a name="l00090"></a><span class="lineno"> 90</span> </div><div class="line"><a name="l00091"></a><span class="lineno"> 91</span>  <span class="comment">// KeyDerivationFunction interface</span></div><div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  <span class="keyword">const</span> <a class="code" href="class_algorithm.html">Algorithm</a> & GetAlgorithm()<span class="keyword"> const </span>{</div><div class="line"><a name="l00093"></a><span class="lineno"> 93</span>  <span class="keywordflow">return</span> *<span class="keyword">this</span>;</div><div class="line"><a name="l00094"></a><span class="lineno"> 94</span>  }</div><div class="line"><a name="l00095"></a><span class="lineno"> 95</span> </div><div class="line"><a name="l00096"></a><span class="lineno"> 96</span>  <span class="keyword">inline</span> <span class="keywordtype">void</span> ValidateParameters(<span class="keywordtype">size_t</span> derivedlen, word64 cost, word64 blockSize, word64 parallelization) <span class="keyword">const</span>;</div><div class="line"><a name="l00097"></a><span class="lineno"> 97</span> };</div><div class="line"><a name="l00098"></a><span class="lineno"> 98</span> </div><div class="line"><a name="l00099"></a><span class="lineno"> 99</span> NAMESPACE_END</div><div class="line"><a name="l00100"></a><span class="lineno"> 100</span> </div><div class="line"><a name="l00101"></a><span class="lineno"> 101</span> <span class="preprocessor">#endif // CRYPTOPP_SCRYPT_H</span></div><div class="ttc" id="cryptlib_8h_html"><div class="ttname"><a href="cryptlib_8h.html">cryptlib.h</a></div><div class="ttdoc">Abstract base classes that provide a uniform interface to this library. </div></div> <div class="ttc" id="class_scrypt_html_ab3b23597d8bcb9af8d55bc8aa57bf709"><div class="ttname"><a href="class_scrypt.html#ab3b23597d8bcb9af8d55bc8aa57bf709">Scrypt::MaxDerivedLength</a></div><div class="ttdeci">size_t MaxDerivedLength() const</div><div class="ttdoc">Determine maximum number of bytes. </div><div class="ttdef"><b>Definition:</b> <a href="scrypt_8h_source.html#l00048">scrypt.h:48</a></div></div> <div class="ttc" id="class_scrypt_html_a102cc305016c030ad04a9ca3fa80bee2"><div class="ttname"><a href="class_scrypt.html#a102cc305016c030ad04a9ca3fa80bee2">Scrypt::AlgorithmName</a></div><div class="ttdeci">std::string AlgorithmName() const</div><div class="ttdoc">Provides the name of this algorithm. </div><div class="ttdef"><b>Definition:</b> <a href="scrypt_8h_source.html#l00043">scrypt.h:43</a></div></div> <div class="ttc" id="secblock_8h_html"><div class="ttname"><a href="secblock_8h.html">secblock.h</a></div><div class="ttdoc">Classes and functions for secure memory allocations. </div></div> <div class="ttc" id="class_algorithm_html"><div class="ttname"><a href="class_algorithm.html">Algorithm</a></div><div class="ttdoc">Interface for all crypto algorithms. </div><div class="ttdef"><b>Definition:</b> <a href="cryptlib_8h_source.html#l00573">cryptlib.h:573</a></div></div> <div class="ttc" id="namespace_crypto_p_p_html"><div class="ttname"><a href="namespace_crypto_p_p.html">CryptoPP</a></div><div class="ttdoc">Crypto++ library namespace. </div></div> <div class="ttc" id="class_scrypt_html"><div class="ttname"><a href="class_scrypt.html">Scrypt</a></div><div class="ttdoc">Scrypt key derivation function. </div><div class="ttdef"><b>Definition:</b> <a href="scrypt_8h_source.html#l00033">scrypt.h:33</a></div></div> <div class="ttc" id="class_key_derivation_function_html"><div class="ttname"><a href="class_key_derivation_function.html">KeyDerivationFunction</a></div><div class="ttdoc">Interface for key derivation functions. </div><div class="ttdef"><b>Definition:</b> <a href="cryptlib_8h_source.html#l01416">cryptlib.h:1416</a></div></div> <div class="ttc" id="class_name_value_pairs_html"><div class="ttname"><a href="class_name_value_pairs.html">NameValuePairs</a></div><div class="ttdoc">Interface for retrieving values given their names. </div><div class="ttdef"><b>Definition:</b> <a href="cryptlib_8h_source.html#l00290">cryptlib.h:290</a></div></div> </div><!-- fragment --></div><!-- contents --> <!-- start footer part --> <hr class="footer"/><address class="footer"><small> Generated on Sun Sep 16 2018 07:58:02 for Crypto++ by  <a href="http://www.doxygen.org/index.html"> <img class="footer" src="doxygen.png" alt="doxygen"/> </a> 1.8.14 </small></address> </body> </html>