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<a href="mersenne_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">// mersenne.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"></span></div><div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment">/// \file mersenne.h</span></div><div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment">/// \brief Class file for Mersenne Twister</span></div><div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment">/// \warning MersenneTwister is suitable for Monte-Carlo simulations, where uniformaly distrubuted</span></div><div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment">/// numbers are required quickly. It should not be used for cryptographic purposes.</span></div><div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment">/// \since Crypto++ 5.6.3</span></div><div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment"></span><span class="preprocessor">#ifndef CRYPTOPP_MERSENNE_TWISTER_H</span></div><div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="preprocessor">#define CRYPTOPP_MERSENNE_TWISTER_H</span></div><div class="line"><a name="l00010"></a><span class="lineno"> 10</span> </div><div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="preprocessor">#include "<a class="code" href="cryptlib_8h.html">cryptlib.h</a>"</span></div><div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="preprocessor">#include "<a class="code" href="secblock_8h.html">secblock.h</a>"</span></div><div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="preprocessor">#include "<a class="code" href="misc_8h.html">misc.h</a>"</span></div><div class="line"><a name="l00014"></a><span class="lineno"> 14</span> </div><div class="line"><a name="l00015"></a><span class="lineno"> 15</span> NAMESPACE_BEGIN(<a class="code" href="namespace_crypto_p_p.html">CryptoPP</a>)</div><div class="line"><a name="l00016"></a><span class="lineno"> 16</span> </div><div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="comment">/// \brief Mersenne Twister class for Monte-Carlo simulations</span></div><div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="comment"></span><span class="comment">/// \tparam K Magic constant</span></div><div class="line"><a name="l00019"></a><span class="lineno"> 19</span> <span class="comment"></span><span class="comment">/// \tparam M Period parameter</span></div><div class="line"><a name="l00020"></a><span class="lineno"> 20</span> <span class="comment"></span><span class="comment">/// \tparam N Size of the state vector</span></div><div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="comment"></span><span class="comment">/// \tparam F Multiplier constant</span></div><div class="line"><a name="l00022"></a><span class="lineno"> 22</span> <span class="comment"></span><span class="comment">/// \tparam S Initial seed</span></div><div class="line"><a name="l00023"></a><span class="lineno"> 23</span> <span class="comment"></span><span class="comment">/// \details Provides the MersenneTwister implementation. The class is a header-only implementation.</span></div><div class="line"><a name="l00024"></a><span class="lineno"> 24</span> <span class="comment"></span><span class="comment">/// \warning MersenneTwister is suitable for simulations, where uniformaly distrubuted numbers are</span></div><div class="line"><a name="l00025"></a><span class="lineno"> 25</span> <span class="comment"></span><span class="comment">/// required quickly. It should not be used for cryptographic purposes.</span></div><div class="line"><a name="l00026"></a><span class="lineno"> 26</span> <span class="comment"></span><span class="comment">/// \sa MT19937, MT19937ar</span></div><div class="line"><a name="l00027"></a><span class="lineno"> 27</span> <span class="comment"></span><span class="comment">/// \since Crypto++ 5.6.3</span></div><div class="line"><a name="l00028"></a><span class="lineno"> 28</span> <span class="comment"></span><span class="keyword">template</span> <<span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> K, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> M, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> N, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> F, word32 S></div><div class="line"><a name="l00029"></a><span class="lineno"><a class="line" href="class_mersenne_twister.html"> 29</a></span> <span class="keyword">class </span><a class="code" href="class_mersenne_twister.html">MersenneTwister</a> : <span class="keyword">public</span> <a class="code" href="class_random_number_generator.html">RandomNumberGenerator</a></div><div class="line"><a name="l00030"></a><span class="lineno"> 30</span> {</div><div class="line"><a name="l00031"></a><span class="lineno"> 31</span> <span class="keyword">public</span>:</div><div class="line"><a name="l00032"></a><span class="lineno"> 32</span>  CRYPTOPP_STATIC_CONSTEXPR <span class="keyword">const</span> <span class="keywordtype">char</span>* StaticAlgorithmName() { <span class="keywordflow">return</span> (S==5489 ? <span class="stringliteral">"MT19937ar"</span> : (S==4537 ? <span class="stringliteral">"MT19937"</span> : <span class="stringliteral">"MT19937x"</span>)); }</div><div class="line"><a name="l00033"></a><span class="lineno"> 33</span> </div><div class="line"><a name="l00034"></a><span class="lineno"> 34</span>  ~<a class="code" href="class_mersenne_twister.html">MersenneTwister</a>() {}</div><div class="line"><a name="l00035"></a><span class="lineno"> 35</span> <span class="comment"></span></div><div class="line"><a name="l00036"></a><span class="lineno"> 36</span> <span class="comment"> /// \brief Construct a Mersenne Twister</span></div><div class="line"><a name="l00037"></a><span class="lineno"> 37</span> <span class="comment"> /// \param seed 32-bit seed</span></div><div class="line"><a name="l00038"></a><span class="lineno"> 38</span> <span class="comment"> /// \details Defaults to template parameter S due to changing algorithm</span></div><div class="line"><a name="l00039"></a><span class="lineno"> 39</span> <span class="comment"> /// parameters over time</span></div><div class="line"><a name="l00040"></a><span class="lineno"><a class="line" href="class_mersenne_twister.html#aa85c73bd3d3fd3c5a8bf8ad6353cc866"> 40</a></span> <span class="comment"></span> <a class="code" href="class_mersenne_twister.html#aa85c73bd3d3fd3c5a8bf8ad6353cc866">MersenneTwister</a>(word32 seed = S) : m_seed(seed), m_idx(N)</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>  Reset(seed);</div><div class="line"><a name="l00043"></a><span class="lineno"> 43</span>  }</div><div class="line"><a name="l00044"></a><span class="lineno"> 44</span> </div><div class="line"><a name="l00045"></a><span class="lineno"><a class="line" href="class_mersenne_twister.html#a9f09a181e0e4785ab95028a8ec6a53d8"> 45</a></span>  <span class="keywordtype">bool</span> <a class="code" href="class_mersenne_twister.html#a9f09a181e0e4785ab95028a8ec6a53d8">CanIncorporateEntropy</a>()<span class="keyword"> const </span>{<span class="keywordflow">return</span> <span class="keyword">true</span>;}</div><div class="line"><a name="l00046"></a><span class="lineno"> 46</span> <span class="comment"></span></div><div class="line"><a name="l00047"></a><span class="lineno"> 47</span> <span class="comment"> /// \brief Update RNG state with additional unpredictable values</span></div><div class="line"><a name="l00048"></a><span class="lineno"> 48</span> <span class="comment"> /// \param input the entropy to add to the generator</span></div><div class="line"><a name="l00049"></a><span class="lineno"> 49</span> <span class="comment"> /// \param length the size of the input buffer</span></div><div class="line"><a name="l00050"></a><span class="lineno"> 50</span> <span class="comment"> /// \details MersenneTwister uses the first 32-bits of <tt>input</tt> to reseed the</span></div><div class="line"><a name="l00051"></a><span class="lineno"> 51</span> <span class="comment"> /// generator. If fewer bytes are provided, then the seed is padded with 0's.</span></div><div class="line"><a name="l00052"></a><span class="lineno"><a class="line" href="class_mersenne_twister.html#a1d2ce0dc810e53a47b0c066f9229ec07"> 52</a></span> <span class="comment"></span> <span class="keywordtype">void</span> <a class="code" href="class_mersenne_twister.html#a1d2ce0dc810e53a47b0c066f9229ec07">IncorporateEntropy</a>(<span class="keyword">const</span> byte *input, <span class="keywordtype">size_t</span> length)</div><div class="line"><a name="l00053"></a><span class="lineno"> 53</span>  {</div><div class="line"><a name="l00054"></a><span class="lineno"> 54</span>  word32 temp = 0;</div><div class="line"><a name="l00055"></a><span class="lineno"> 55</span>  ::memcpy(&temp, input, <a class="code" href="misc_8h.html#abe412b0409249cb54899e97bc7d86424">STDMIN</a>(<span class="keyword">sizeof</span>(temp), length));</div><div class="line"><a name="l00056"></a><span class="lineno"> 56</span>  Reset(temp);</div><div class="line"><a name="l00057"></a><span class="lineno"> 57</span> </div><div class="line"><a name="l00058"></a><span class="lineno"> 58</span>  <span class="comment">// Wipe temp</span></div><div class="line"><a name="l00059"></a><span class="lineno"> 59</span>  <a class="code" href="misc_8h.html#a4994f3480634e5f1435fd71f9b652c38">SecureWipeArray</a>(&temp, 1);</div><div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  }</div><div class="line"><a name="l00061"></a><span class="lineno"> 61</span> <span class="comment"></span></div><div class="line"><a name="l00062"></a><span class="lineno"> 62</span> <span class="comment"> /// \brief Generate random array of bytes</span></div><div class="line"><a name="l00063"></a><span class="lineno"> 63</span> <span class="comment"> /// \param output byte buffer</span></div><div class="line"><a name="l00064"></a><span class="lineno"> 64</span> <span class="comment"> /// \param size length of the buffer, in bytes</span></div><div class="line"><a name="l00065"></a><span class="lineno"> 65</span> <span class="comment"> /// \details Bytes are written to output in big endian order. If output length</span></div><div class="line"><a name="l00066"></a><span class="lineno"> 66</span> <span class="comment"> /// is not a multiple of word32, then unused bytes are not accumulated for subsequent</span></div><div class="line"><a name="l00067"></a><span class="lineno"> 67</span> <span class="comment"> /// calls to GenerateBlock. Rather, the unused tail bytes are discarded, and the</span></div><div class="line"><a name="l00068"></a><span class="lineno"> 68</span> <span class="comment"> /// stream is continued at the next word32 boundary from the state array.</span></div><div class="line"><a name="l00069"></a><span class="lineno"><a class="line" href="class_mersenne_twister.html#a2cc6a68d00adaca7f72cdbf72b19699d"> 69</a></span> <span class="comment"></span> <span class="keywordtype">void</span> <a class="code" href="class_mersenne_twister.html#a2cc6a68d00adaca7f72cdbf72b19699d">GenerateBlock</a>(byte *output, <span class="keywordtype">size_t</span> size)</div><div class="line"><a name="l00070"></a><span class="lineno"> 70</span>  {</div><div class="line"><a name="l00071"></a><span class="lineno"> 71</span>  <span class="comment">// Handle word32 size blocks</span></div><div class="line"><a name="l00072"></a><span class="lineno"> 72</span>  word32 temp;</div><div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  <span class="keywordflow">for</span> (<span class="keywordtype">size_t</span> i=0; i < size/4; i++, output += 4)</div><div class="line"><a name="l00074"></a><span class="lineno"> 74</span>  {</div><div class="line"><a name="l00075"></a><span class="lineno"> 75</span>  temp = NextMersenneWord();</div><div class="line"><a name="l00076"></a><span class="lineno"> 76</span>  memcpy(output, &temp, 4);</div><div class="line"><a name="l00077"></a><span class="lineno"> 77</span>  }</div><div class="line"><a name="l00078"></a><span class="lineno"> 78</span> </div><div class="line"><a name="l00079"></a><span class="lineno"> 79</span>  <span class="comment">// No tail bytes</span></div><div class="line"><a name="l00080"></a><span class="lineno"> 80</span>  <span class="keywordflow">if</span> (size%4 == 0)</div><div class="line"><a name="l00081"></a><span class="lineno"> 81</span>  {</div><div class="line"><a name="l00082"></a><span class="lineno"> 82</span>  <span class="comment">// Wipe temp</span></div><div class="line"><a name="l00083"></a><span class="lineno"> 83</span>  <a class="code" href="misc_8h.html#a4994f3480634e5f1435fd71f9b652c38">SecureWipeArray</a>(&temp, 1);</div><div class="line"><a name="l00084"></a><span class="lineno"> 84</span>  <span class="keywordflow">return</span>;</div><div class="line"><a name="l00085"></a><span class="lineno"> 85</span>  }</div><div class="line"><a name="l00086"></a><span class="lineno"> 86</span> </div><div class="line"><a name="l00087"></a><span class="lineno"> 87</span>  <span class="comment">// Handle tail bytes</span></div><div class="line"><a name="l00088"></a><span class="lineno"> 88</span>  temp = NextMersenneWord();</div><div class="line"><a name="l00089"></a><span class="lineno"> 89</span>  <span class="keywordflow">switch</span> (size%4)</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="keywordflow">case</span> 3: output[2] = CRYPTOPP_GET_BYTE_AS_BYTE(temp, 1); <span class="comment">/* fall through */</span></div><div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  <span class="keywordflow">case</span> 2: output[1] = CRYPTOPP_GET_BYTE_AS_BYTE(temp, 2); <span class="comment">/* fall through */</span></div><div class="line"><a name="l00093"></a><span class="lineno"> 93</span>  <span class="keywordflow">case</span> 1: output[0] = CRYPTOPP_GET_BYTE_AS_BYTE(temp, 3); <span class="keywordflow">break</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>  <span class="keywordflow">default</span>: <a class="code" href="trap_8h.html#adf3b392588bc94cbeae9f415a78c7b95">CRYPTOPP_ASSERT</a>(0); ;;</div><div class="line"><a name="l00096"></a><span class="lineno"> 96</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>  <span class="comment">// Wipe temp</span></div><div class="line"><a name="l00099"></a><span class="lineno"> 99</span>  <a class="code" href="misc_8h.html#a4994f3480634e5f1435fd71f9b652c38">SecureWipeArray</a>(&temp, 1);</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="comment"></span></div><div class="line"><a name="l00102"></a><span class="lineno"> 102</span> <span class="comment"> /// \brief Generate a random 32-bit word in the range min to max, inclusive</span></div><div class="line"><a name="l00103"></a><span class="lineno"> 103</span> <span class="comment"> /// \returns random 32-bit word in the range min to max, inclusive</span></div><div class="line"><a name="l00104"></a><span class="lineno"> 104</span> <span class="comment"> /// \details If the 32-bit candidate is not within the range, then it is discarded</span></div><div class="line"><a name="l00105"></a><span class="lineno"> 105</span> <span class="comment"> /// and a new candidate is used.</span></div><div class="line"><a name="l00106"></a><span class="lineno"><a class="line" href="class_mersenne_twister.html#adf08e5d038201e24b423c0563fdedbb0"> 106</a></span> <span class="comment"></span> word32 <a class="code" href="class_mersenne_twister.html#adf08e5d038201e24b423c0563fdedbb0">GenerateWord32</a>(word32 min=0, word32 max=0xffffffffL)</div><div class="line"><a name="l00107"></a><span class="lineno"> 107</span>  {</div><div class="line"><a name="l00108"></a><span class="lineno"> 108</span>  <span class="keyword">const</span> word32 range = max-min;</div><div class="line"><a name="l00109"></a><span class="lineno"> 109</span>  <span class="keywordflow">if</span> (range == 0xffffffffL)</div><div class="line"><a name="l00110"></a><span class="lineno"> 110</span>  <span class="keywordflow">return</span> NextMersenneWord();</div><div class="line"><a name="l00111"></a><span class="lineno"> 111</span> </div><div class="line"><a name="l00112"></a><span class="lineno"> 112</span>  <span class="keyword">const</span> <span class="keywordtype">int</span> maxBits = <a class="code" href="misc_8h.html#a3c5964768bc94670ad2bc3f218d9367f">BitPrecision</a>(range);</div><div class="line"><a name="l00113"></a><span class="lineno"> 113</span>  word32 value;</div><div class="line"><a name="l00114"></a><span class="lineno"> 114</span> </div><div class="line"><a name="l00115"></a><span class="lineno"> 115</span>  <span class="keywordflow">do</span>{</div><div class="line"><a name="l00116"></a><span class="lineno"> 116</span>  value = <a class="code" href="misc_8h.html#a616a7f0365c4947b0c8a44606c525a62">Crop</a>(NextMersenneWord(), maxBits);</div><div class="line"><a name="l00117"></a><span class="lineno"> 117</span>  } <span class="keywordflow">while</span> (value > range);</div><div class="line"><a name="l00118"></a><span class="lineno"> 118</span> </div><div class="line"><a name="l00119"></a><span class="lineno"> 119</span>  <span class="keywordflow">return</span> value+min;</div><div class="line"><a name="l00120"></a><span class="lineno"> 120</span>  }</div><div class="line"><a name="l00121"></a><span class="lineno"> 121</span> <span class="comment"></span></div><div class="line"><a name="l00122"></a><span class="lineno"> 122</span> <span class="comment"> /// \brief Generate and discard n bytes</span></div><div class="line"><a name="l00123"></a><span class="lineno"> 123</span> <span class="comment"> /// \param n the number of bytes to discard, rounded up to a <tt>word32</tt> size</span></div><div class="line"><a name="l00124"></a><span class="lineno"> 124</span> <span class="comment"> /// \details If n is not a multiple of <tt>word32</tt>, then unused bytes are</span></div><div class="line"><a name="l00125"></a><span class="lineno"> 125</span> <span class="comment"> /// not accumulated for subsequent calls to GenerateBlock. Rather, the unused</span></div><div class="line"><a name="l00126"></a><span class="lineno"> 126</span> <span class="comment"> /// tail bytes are discarded, and the stream is continued at the next</span></div><div class="line"><a name="l00127"></a><span class="lineno"> 127</span> <span class="comment"> /// <tt>word32</tt> boundary from the state array.</span></div><div class="line"><a name="l00128"></a><span class="lineno"><a class="line" href="class_mersenne_twister.html#a9ea210a209dea0f0a2719538d6dae0a4"> 128</a></span> <span class="comment"></span> <span class="keywordtype">void</span> <a class="code" href="class_mersenne_twister.html#a9ea210a209dea0f0a2719538d6dae0a4">DiscardBytes</a>(<span class="keywordtype">size_t</span> n)</div><div class="line"><a name="l00129"></a><span class="lineno"> 129</span>  {</div><div class="line"><a name="l00130"></a><span class="lineno"> 130</span>  <span class="keywordflow">for</span>(<span class="keywordtype">size_t</span> i=0; i < <a class="code" href="misc_8h.html#a57a219d44f45272a1f3b3f17a656000a">RoundUpToMultipleOf</a>(n, 4U); i++)</div><div class="line"><a name="l00131"></a><span class="lineno"> 131</span>  NextMersenneWord();</div><div class="line"><a name="l00132"></a><span class="lineno"> 132</span>  }</div><div class="line"><a name="l00133"></a><span class="lineno"> 133</span> </div><div class="line"><a name="l00134"></a><span class="lineno"> 134</span> <span class="keyword">protected</span>:</div><div class="line"><a name="l00135"></a><span class="lineno"> 135</span> </div><div class="line"><a name="l00136"></a><span class="lineno"> 136</span>  <span class="keywordtype">void</span> Reset(word32 seed)</div><div class="line"><a name="l00137"></a><span class="lineno"> 137</span>  {</div><div class="line"><a name="l00138"></a><span class="lineno"> 138</span>  m_seed = seed;</div><div class="line"><a name="l00139"></a><span class="lineno"> 139</span>  m_idx = N;</div><div class="line"><a name="l00140"></a><span class="lineno"> 140</span> </div><div class="line"><a name="l00141"></a><span class="lineno"> 141</span>  m_state[0] = seed;</div><div class="line"><a name="l00142"></a><span class="lineno"> 142</span>  <span class="keywordflow">for</span> (<span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i = 1; i < N+1; i++)</div><div class="line"><a name="l00143"></a><span class="lineno"> 143</span>  m_state[i] = word32(F * (m_state[i-1] ^ (m_state[i-1] >> 30)) + i);</div><div class="line"><a name="l00144"></a><span class="lineno"> 144</span>  }</div><div class="line"><a name="l00145"></a><span class="lineno"> 145</span> <span class="comment"></span></div><div class="line"><a name="l00146"></a><span class="lineno"> 146</span> <span class="comment"> /// \brief Returns the next 32-bit word from the state array</span></div><div class="line"><a name="l00147"></a><span class="lineno"> 147</span> <span class="comment"> /// \returns the next 32-bit word from the state array</span></div><div class="line"><a name="l00148"></a><span class="lineno"> 148</span> <span class="comment"> /// \details fetches the next word frm the state array, performs bit operations on</span></div><div class="line"><a name="l00149"></a><span class="lineno"> 149</span> <span class="comment"> /// it, and then returns the value to the caller.</span></div><div class="line"><a name="l00150"></a><span class="lineno"> 150</span> <span class="comment"></span> word32 NextMersenneWord()</div><div class="line"><a name="l00151"></a><span class="lineno"> 151</span>  {</div><div class="line"><a name="l00152"></a><span class="lineno"> 152</span>  <span class="keywordflow">if</span> (m_idx >= N) { Twist(); }</div><div class="line"><a name="l00153"></a><span class="lineno"> 153</span> </div><div class="line"><a name="l00154"></a><span class="lineno"> 154</span>  word32 temp = m_state[m_idx++];</div><div class="line"><a name="l00155"></a><span class="lineno"> 155</span> </div><div class="line"><a name="l00156"></a><span class="lineno"> 156</span>  temp ^= (temp >> 11);</div><div class="line"><a name="l00157"></a><span class="lineno"> 157</span>  temp ^= (temp << 7) & 0x9D2C5680; <span class="comment">// 0x9D2C5680 (2636928640)</span></div><div class="line"><a name="l00158"></a><span class="lineno"> 158</span>  temp ^= (temp << 15) & 0xEFC60000; <span class="comment">// 0xEFC60000 (4022730752)</span></div><div class="line"><a name="l00159"></a><span class="lineno"> 159</span> </div><div class="line"><a name="l00160"></a><span class="lineno"> 160</span>  <span class="keywordflow">return</span> temp ^ (temp >> 18);</div><div class="line"><a name="l00161"></a><span class="lineno"> 161</span>  }</div><div class="line"><a name="l00162"></a><span class="lineno"> 162</span> <span class="comment"></span></div><div class="line"><a name="l00163"></a><span class="lineno"> 163</span> <span class="comment"> /// \brief Performs the twist operaton on the state array</span></div><div class="line"><a name="l00164"></a><span class="lineno"> 164</span> <span class="comment"></span> <span class="keywordtype">void</span> Twist()</div><div class="line"><a name="l00165"></a><span class="lineno"> 165</span>  {</div><div class="line"><a name="l00166"></a><span class="lineno"> 166</span>  <span class="keyword">static</span> <span class="keyword">const</span> word32 magic[2]={0x0UL, K};</div><div class="line"><a name="l00167"></a><span class="lineno"> 167</span>  word32 kk, temp;</div><div class="line"><a name="l00168"></a><span class="lineno"> 168</span> </div><div class="line"><a name="l00169"></a><span class="lineno"> 169</span>  <a class="code" href="trap_8h.html#adf3b392588bc94cbeae9f415a78c7b95">CRYPTOPP_ASSERT</a>(N >= M);</div><div class="line"><a name="l00170"></a><span class="lineno"> 170</span>  <span class="keywordflow">for</span> (kk=0;kk<N-M;kk++)</div><div class="line"><a name="l00171"></a><span class="lineno"> 171</span>  {</div><div class="line"><a name="l00172"></a><span class="lineno"> 172</span>  temp = (m_state[kk] & 0x80000000)|(m_state[kk+1] & 0x7FFFFFFF);</div><div class="line"><a name="l00173"></a><span class="lineno"> 173</span>  m_state[kk] = m_state[kk+M] ^ (temp >> 1) ^ magic[temp & 0x1UL];</div><div class="line"><a name="l00174"></a><span class="lineno"> 174</span>  }</div><div class="line"><a name="l00175"></a><span class="lineno"> 175</span> </div><div class="line"><a name="l00176"></a><span class="lineno"> 176</span>  <span class="keywordflow">for</span> (;kk<N-1;kk++)</div><div class="line"><a name="l00177"></a><span class="lineno"> 177</span>  {</div><div class="line"><a name="l00178"></a><span class="lineno"> 178</span>  temp = (m_state[kk] & 0x80000000)|(m_state[kk+1] & 0x7FFFFFFF);</div><div class="line"><a name="l00179"></a><span class="lineno"> 179</span>  m_state[kk] = m_state[kk+(M-N)] ^ (temp >> 1) ^ magic[temp & 0x1UL];</div><div class="line"><a name="l00180"></a><span class="lineno"> 180</span>  }</div><div class="line"><a name="l00181"></a><span class="lineno"> 181</span> </div><div class="line"><a name="l00182"></a><span class="lineno"> 182</span>  temp = (m_state[N-1] & 0x80000000)|(m_state[0] & 0x7FFFFFFF);</div><div class="line"><a name="l00183"></a><span class="lineno"> 183</span>  m_state[N-1] = m_state[M-1] ^ (temp >> 1) ^ magic[temp & 0x1UL];</div><div class="line"><a name="l00184"></a><span class="lineno"> 184</span> </div><div class="line"><a name="l00185"></a><span class="lineno"> 185</span>  <span class="comment">// Reset index</span></div><div class="line"><a name="l00186"></a><span class="lineno"> 186</span>  m_idx = 0;</div><div class="line"><a name="l00187"></a><span class="lineno"> 187</span> </div><div class="line"><a name="l00188"></a><span class="lineno"> 188</span>  <span class="comment">// Wipe temp</span></div><div class="line"><a name="l00189"></a><span class="lineno"> 189</span>  <a class="code" href="misc_8h.html#a4994f3480634e5f1435fd71f9b652c38">SecureWipeArray</a>(&temp, 1);</div><div class="line"><a name="l00190"></a><span class="lineno"> 190</span>  }</div><div class="line"><a name="l00191"></a><span class="lineno"> 191</span> </div><div class="line"><a name="l00192"></a><span class="lineno"> 192</span> <span class="keyword">private</span>:</div><div class="line"><a name="l00193"></a><span class="lineno"> 193</span> <span class="comment"></span></div><div class="line"><a name="l00194"></a><span class="lineno"> 194</span> <span class="comment"> /// \brief 32-bit word state array of size N</span></div><div class="line"><a name="l00195"></a><span class="lineno"> 195</span> <span class="comment"></span> <a class="code" href="class_fixed_size_sec_block.html">FixedSizeSecBlock<word32, N+1></a> m_state;<span class="comment"></span></div><div class="line"><a name="l00196"></a><span class="lineno"> 196</span> <span class="comment"> /// \brief the value used to seed the generator</span></div><div class="line"><a name="l00197"></a><span class="lineno"> 197</span> <span class="comment"></span> word32 m_seed;<span class="comment"></span></div><div class="line"><a name="l00198"></a><span class="lineno"> 198</span> <span class="comment"> /// \brief the current index into the state array</span></div><div class="line"><a name="l00199"></a><span class="lineno"> 199</span> <span class="comment"></span> word32 m_idx;</div><div class="line"><a name="l00200"></a><span class="lineno"> 200</span> };</div><div class="line"><a name="l00201"></a><span class="lineno"> 201</span> <span class="comment"></span></div><div class="line"><a name="l00202"></a><span class="lineno"> 202</span> <span class="comment">/// \brief Original MT19937 generator provided in the ACM paper.</span></div><div class="line"><a name="l00203"></a><span class="lineno"> 203</span> <span class="comment">/// \details MT19937 uses 4537 as default initial seed.</span></div><div class="line"><a name="l00204"></a><span class="lineno"> 204</span> <span class="comment">/// \sa MT19937ar, <A HREF="http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/ARTICLES/mt.pdf">Mersenne twister:</span></div><div class="line"><a name="l00205"></a><span class="lineno"> 205</span> <span class="comment">/// a 623-dimensionally equidistributed uniform pseudo-random number generator</A></span></div><div class="line"><a name="l00206"></a><span class="lineno"> 206</span> <span class="comment">/// \since Crypto++ 5.6.3</span></div><div class="line"><a name="l00207"></a><span class="lineno"> 207</span> <span class="comment"></span><span class="preprocessor">#if CRYPTOPP_DOXYGEN_PROCESSING</span></div><div class="line"><a name="l00208"></a><span class="lineno"><a class="line" href="class_m_t19937.html"> 208</a></span> <span class="keyword">class </span><a class="code" href="class_m_t19937.html">MT19937</a> : <span class="keyword">public</span> <a class="code" href="class_mersenne_twister.html">MersenneTwister</a><0x9908B0DF <span class="comment">/*2567483615*/</span>, 397, 624, 0x10DCD <span class="comment">/*69069*/</span>, 4537> {};</div><div class="line"><a name="l00209"></a><span class="lineno"> 209</span> <span class="preprocessor">#else</span></div><div class="line"><a name="l00210"></a><span class="lineno"> 210</span> <span class="keyword">typedef</span> <a class="code" href="class_mersenne_twister.html">MersenneTwister</a><0x9908B0DF <span class="comment">/*2567483615*/</span>, 397, 624, 0x10DCD <span class="comment">/*69069*/</span>, 4537> <a class="code" href="class_m_t19937.html">MT19937</a>;</div><div class="line"><a name="l00211"></a><span class="lineno"> 211</span> <span class="preprocessor">#endif</span></div><div class="line"><a name="l00212"></a><span class="lineno"> 212</span> <span class="comment"></span></div><div class="line"><a name="l00213"></a><span class="lineno"> 213</span> <span class="comment">/// \brief Updated MT19937 generator adapted to provide an array for initialization.</span></div><div class="line"><a name="l00214"></a><span class="lineno"> 214</span> <span class="comment">/// \details MT19937 uses 5489 as default initial seed. Use this generator when interoperating with C++11's</span></div><div class="line"><a name="l00215"></a><span class="lineno"> 215</span> <span class="comment">/// mt19937 class.</span></div><div class="line"><a name="l00216"></a><span class="lineno"> 216</span> <span class="comment">/// \sa MT19937, <A HREF="http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/emt19937ar.html">Mersenne Twister</span></div><div class="line"><a name="l00217"></a><span class="lineno"> 217</span> <span class="comment">/// with improved initialization</A></span></div><div class="line"><a name="l00218"></a><span class="lineno"> 218</span> <span class="comment">/// \since Crypto++ 5.6.3</span></div><div class="line"><a name="l00219"></a><span class="lineno"> 219</span> <span class="comment"></span><span class="preprocessor">#if CRYPTOPP_DOXYGEN_PROCESSING</span></div><div class="line"><a name="l00220"></a><span class="lineno"><a class="line" href="class_m_t19937ar.html"> 220</a></span> <span class="keyword">class </span><a class="code" href="class_m_t19937ar.html">MT19937ar</a> : <span class="keyword">public</span> <a class="code" href="class_mersenne_twister.html">MersenneTwister</a><0x9908B0DF <span class="comment">/*2567483615*/</span>, 397, 624, 0x6C078965 <span class="comment">/*1812433253*/</span>, 5489> {};</div><div class="line"><a name="l00221"></a><span class="lineno"> 221</span> <span class="preprocessor">#else</span></div><div class="line"><a name="l00222"></a><span class="lineno"> 222</span> <span class="keyword">typedef</span> <a class="code" href="class_mersenne_twister.html">MersenneTwister</a><0x9908B0DF <span class="comment">/*2567483615*/</span>, 397, 624, 0x6C078965 <span class="comment">/*1812433253*/</span>, 5489> <a class="code" href="class_m_t19937ar.html">MT19937ar</a>;</div><div class="line"><a name="l00223"></a><span class="lineno"> 223</span> <span class="preprocessor">#endif</span></div><div class="line"><a name="l00224"></a><span class="lineno"> 224</span> </div><div class="line"><a name="l00225"></a><span class="lineno"> 225</span> NAMESPACE_END</div><div class="line"><a name="l00226"></a><span class="lineno"> 226</span> </div><div class="line"><a name="l00227"></a><span class="lineno"> 227</span> <span class="preprocessor">#endif // CRYPTOPP_MERSENNE_TWISTER_H</span></div><div class="line"><a name="l00228"></a><span class="lineno"> 228</span> </div><div class="ttc" id="misc_8h_html"><div class="ttname"><a href="misc_8h.html">misc.h</a></div><div class="ttdoc">Utility functions for the Crypto++ library. </div></div>
<div class="ttc" id="class_mersenne_twister_html"><div class="ttname"><a href="class_mersenne_twister.html">MersenneTwister</a></div><div class="ttdoc">Mersenne Twister class for Monte-Carlo simulations. </div><div class="ttdef"><b>Definition:</b> <a href="mersenne_8h_source.html#l00029">mersenne.h:29</a></div></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_random_number_generator_html"><div class="ttname"><a href="class_random_number_generator.html">RandomNumberGenerator</a></div><div class="ttdoc">Interface for random number generators. </div><div class="ttdef"><b>Definition:</b> <a href="cryptlib_8h_source.html#l01330">cryptlib.h:1330</a></div></div>
<div class="ttc" id="class_mersenne_twister_html_aa85c73bd3d3fd3c5a8bf8ad6353cc866"><div class="ttname"><a href="class_mersenne_twister.html#aa85c73bd3d3fd3c5a8bf8ad6353cc866">MersenneTwister::MersenneTwister</a></div><div class="ttdeci">MersenneTwister(word32 seed=S)</div><div class="ttdoc">Construct a Mersenne Twister. </div><div class="ttdef"><b>Definition:</b> <a href="mersenne_8h_source.html#l00040">mersenne.h:40</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="misc_8h_html_a4994f3480634e5f1435fd71f9b652c38"><div class="ttname"><a href="misc_8h.html#a4994f3480634e5f1435fd71f9b652c38">SecureWipeArray</a></div><div class="ttdeci">void SecureWipeArray(T *buf, size_t n)</div><div class="ttdoc">Sets each element of an array to 0. </div><div class="ttdef"><b>Definition:</b> <a href="misc_8h_source.html#l01275">misc.h:1275</a></div></div>
<div class="ttc" id="class_mersenne_twister_html_a9f09a181e0e4785ab95028a8ec6a53d8"><div class="ttname"><a href="class_mersenne_twister.html#a9f09a181e0e4785ab95028a8ec6a53d8">MersenneTwister::CanIncorporateEntropy</a></div><div class="ttdeci">bool CanIncorporateEntropy() const</div><div class="ttdoc">Determines if a generator can accept additional entropy. </div><div class="ttdef"><b>Definition:</b> <a href="mersenne_8h_source.html#l00045">mersenne.h:45</a></div></div>
<div class="ttc" id="misc_8h_html_a616a7f0365c4947b0c8a44606c525a62"><div class="ttname"><a href="misc_8h.html#a616a7f0365c4947b0c8a44606c525a62">Crop</a></div><div class="ttdeci">T Crop(T value, size_t bits)</div><div class="ttdoc">Truncates the value to the specified number of bits. </div><div class="ttdef"><b>Definition:</b> <a href="misc_8h_source.html#l00778">misc.h:778</a></div></div>
<div class="ttc" id="class_mersenne_twister_html_a9ea210a209dea0f0a2719538d6dae0a4"><div class="ttname"><a href="class_mersenne_twister.html#a9ea210a209dea0f0a2719538d6dae0a4">MersenneTwister::DiscardBytes</a></div><div class="ttdeci">void DiscardBytes(size_t n)</div><div class="ttdoc">Generate and discard n bytes. </div><div class="ttdef"><b>Definition:</b> <a href="mersenne_8h_source.html#l00128">mersenne.h:128</a></div></div>
<div class="ttc" id="class_fixed_size_sec_block_html"><div class="ttname"><a href="class_fixed_size_sec_block.html">FixedSizeSecBlock< word32, N+1 ></a></div></div>
<div class="ttc" id="class_m_t19937_html"><div class="ttname"><a href="class_m_t19937.html">MT19937</a></div><div class="ttdoc">Original MT19937 generator provided in the ACM paper. </div><div class="ttdef"><b>Definition:</b> <a href="mersenne_8h_source.html#l00208">mersenne.h:208</a></div></div>
<div class="ttc" id="class_mersenne_twister_html_a2cc6a68d00adaca7f72cdbf72b19699d"><div class="ttname"><a href="class_mersenne_twister.html#a2cc6a68d00adaca7f72cdbf72b19699d">MersenneTwister::GenerateBlock</a></div><div class="ttdeci">void GenerateBlock(byte *output, size_t size)</div><div class="ttdoc">Generate random array of bytes. </div><div class="ttdef"><b>Definition:</b> <a href="mersenne_8h_source.html#l00069">mersenne.h:69</a></div></div>
<div class="ttc" id="misc_8h_html_abe412b0409249cb54899e97bc7d86424"><div class="ttname"><a href="misc_8h.html#abe412b0409249cb54899e97bc7d86424">STDMIN</a></div><div class="ttdeci">const T & STDMIN(const T &a, const T &b)</div><div class="ttdoc">Replacement function for std::min. </div><div class="ttdef"><b>Definition:</b> <a href="misc_8h_source.html#l00507">misc.h:507</a></div></div>
<div class="ttc" id="trap_8h_html_adf3b392588bc94cbeae9f415a78c7b95"><div class="ttname"><a href="trap_8h.html#adf3b392588bc94cbeae9f415a78c7b95">CRYPTOPP_ASSERT</a></div><div class="ttdeci">#define CRYPTOPP_ASSERT(exp)</div><div class="ttdoc">Debugging and diagnostic assertion. </div><div class="ttdef"><b>Definition:</b> <a href="trap_8h_source.html#l00060">trap.h:60</a></div></div>
<div class="ttc" id="class_m_t19937ar_html"><div class="ttname"><a href="class_m_t19937ar.html">MT19937ar</a></div><div class="ttdoc">Updated MT19937 generator adapted to provide an array for initialization. </div><div class="ttdef"><b>Definition:</b> <a href="mersenne_8h_source.html#l00220">mersenne.h:220</a></div></div>
<div class="ttc" id="misc_8h_html_a57a219d44f45272a1f3b3f17a656000a"><div class="ttname"><a href="misc_8h.html#a57a219d44f45272a1f3b3f17a656000a">RoundUpToMultipleOf</a></div><div class="ttdeci">T1 RoundUpToMultipleOf(const T1 &n, const T2 &m)</div><div class="ttdoc">Rounds a value up to a multiple of a second value. </div><div class="ttdef"><b>Definition:</b> <a href="misc_8h_source.html#l00971">misc.h:971</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_mersenne_twister_html_adf08e5d038201e24b423c0563fdedbb0"><div class="ttname"><a href="class_mersenne_twister.html#adf08e5d038201e24b423c0563fdedbb0">MersenneTwister::GenerateWord32</a></div><div class="ttdeci">word32 GenerateWord32(word32 min=0, word32 max=0xffffffffL)</div><div class="ttdoc">Generate a random 32-bit word in the range min to max, inclusive. </div><div class="ttdef"><b>Definition:</b> <a href="mersenne_8h_source.html#l00106">mersenne.h:106</a></div></div>
<div class="ttc" id="class_mersenne_twister_html_a1d2ce0dc810e53a47b0c066f9229ec07"><div class="ttname"><a href="class_mersenne_twister.html#a1d2ce0dc810e53a47b0c066f9229ec07">MersenneTwister::IncorporateEntropy</a></div><div class="ttdeci">void IncorporateEntropy(const byte *input, size_t length)</div><div class="ttdoc">Update RNG state with additional unpredictable values. </div><div class="ttdef"><b>Definition:</b> <a href="mersenne_8h_source.html#l00052">mersenne.h:52</a></div></div>
<div class="ttc" id="misc_8h_html_a3c5964768bc94670ad2bc3f218d9367f"><div class="ttname"><a href="misc_8h.html#a3c5964768bc94670ad2bc3f218d9367f">BitPrecision</a></div><div class="ttdeci">unsigned int BitPrecision(const T &value)</div><div class="ttdoc">Returns the number of bits required for a value. </div><div class="ttdef"><b>Definition:</b> <a href="misc_8h_source.html#l00694">misc.h:694</a></div></div>
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0a67b807a02637f2cae68649d519a89d
>
files
>
2437
