<!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>Crypto++: square.cpp Source File</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<link href="doxygen.css" rel="stylesheet" type="text/css"/>
</head>
<body>
<!-- Generated by Doxygen 1.7.4 -->
<div id="top">
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 56px;">
<td style="padding-left: 0.5em;">
<div id="projectname">Crypto++</div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="navrow1" class="tabs">
<ul class="tablist">
<li><a href="index.html"><span>Main Page</span></a></li>
<li><a href="namespaces.html"><span>Namespaces</span></a></li>
<li><a href="annotated.html"><span>Classes</span></a></li>
<li class="current"><a href="files.html"><span>Files</span></a></li>
</ul>
</div>
<div id="navrow2" class="tabs2">
<ul class="tablist">
<li><a href="files.html"><span>File List</span></a></li>
<li><a href="globals.html"><span>File Members</span></a></li>
</ul>
</div>
<div class="header">
<div class="headertitle">
<div class="title">square.cpp</div> </div>
</div>
<div class="contents">
<div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">// square.cpp - written and placed in the public domain by Wei Dai</span>
<a name="l00002"></a>00002 <span class="comment">// Based on Paulo S.L.M. Barreto's public domain implementation</span>
<a name="l00003"></a>00003
<a name="l00004"></a>00004 <span class="preprocessor">#include "pch.h"</span>
<a name="l00005"></a>00005 <span class="preprocessor">#include "<a class="code" href="square_8h.html">square.h</a>"</span>
<a name="l00006"></a>00006 <span class="preprocessor">#include "misc.h"</span>
<a name="l00007"></a>00007 <span class="preprocessor">#include "gf256.h"</span>
<a name="l00008"></a>00008
<a name="l00009"></a>00009 NAMESPACE_BEGIN(CryptoPP)
<a name="l00010"></a>00010
<a name="l00011"></a>00011 <span class="comment">// apply theta to a roundkey</span>
<a name="l00012"></a>00012 static <span class="keywordtype">void</span> SquareTransform (word32 in[4], word32 out[4])
<a name="l00013"></a>00013 {
<a name="l00014"></a>00014 <span class="keyword">static</span> <span class="keyword">const</span> byte G[4][4] =
<a name="l00015"></a>00015 {
<a name="l00016"></a>00016 0x02U, 0x01U, 0x01U, 0x03U,
<a name="l00017"></a>00017 0x03U, 0x02U, 0x01U, 0x01U,
<a name="l00018"></a>00018 0x01U, 0x03U, 0x02U, 0x01U,
<a name="l00019"></a>00019 0x01U, 0x01U, 0x03U, 0x02U
<a name="l00020"></a>00020 };
<a name="l00021"></a>00021
<a name="l00022"></a>00022 <a class="code" href="class_g_f256.html" title="GF(256) with polynomial basis.">GF256</a> gf256(0xf5);
<a name="l00023"></a>00023
<a name="l00024"></a>00024 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i < 4; i++)
<a name="l00025"></a>00025 {
<a name="l00026"></a>00026 word32 temp = 0;
<a name="l00027"></a>00027 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> j = 0; j < 4; j++)
<a name="l00028"></a>00028 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> k = 0; k < 4; k++)
<a name="l00029"></a>00029 temp ^= (word32)gf256.Multiply(GETBYTE(in[i], 3-k), G[k][j]) << ((3-j)*8);
<a name="l00030"></a>00030 out[i] = temp;
<a name="l00031"></a>00031 }
<a name="l00032"></a>00032 }
<a name="l00033"></a>00033
<a name="l00034"></a>00034 <span class="preprocessor">#define roundkeys(i, j) m_roundkeys[(i)*4+(j)]</span>
<a name="l00035"></a>00035 <span class="preprocessor"></span><span class="preprocessor">#define roundkeys4(i) (m_roundkeys+(i)*4)</span>
<a name="l00036"></a>00036 <span class="preprocessor"></span>
<a name="l00037"></a>00037 <span class="keywordtype">void</span> Square::Base::UncheckedSetKey(<span class="keyword">const</span> byte *userKey, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> length, <span class="keyword">const</span> <a class="code" href="class_name_value_pairs.html" title="interface for retrieving values given their names">NameValuePairs</a> &)
<a name="l00038"></a>00038 {
<a name="l00039"></a>00039 AssertValidKeyLength(length);
<a name="l00040"></a>00040
<a name="l00041"></a>00041 <span class="keyword">static</span> <span class="keyword">const</span> word32 offset[ROUNDS] = {
<a name="l00042"></a>00042 0x01000000UL, 0x02000000UL, 0x04000000UL, 0x08000000UL,
<a name="l00043"></a>00043 0x10000000UL, 0x20000000UL, 0x40000000UL, 0x80000000UL,
<a name="l00044"></a>00044 };
<a name="l00045"></a>00045
<a name="l00046"></a>00046 GetUserKey(BIG_ENDIAN_ORDER, m_roundkeys.data(), KEYLENGTH/4, userKey, KEYLENGTH);
<a name="l00047"></a>00047
<a name="l00048"></a>00048 <span class="comment">/* apply the key evolution function */</span>
<a name="l00049"></a>00049 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 1; i < ROUNDS+1; i++)
<a name="l00050"></a>00050 {
<a name="l00051"></a>00051 roundkeys(i, 0) = roundkeys(i-1, 0) ^ rotlFixed(roundkeys(i-1, 3), 8U) ^ offset[i-1];
<a name="l00052"></a>00052 roundkeys(i, 1) = roundkeys(i-1, 1) ^ roundkeys(i, 0);
<a name="l00053"></a>00053 roundkeys(i, 2) = roundkeys(i-1, 2) ^ roundkeys(i, 1);
<a name="l00054"></a>00054 roundkeys(i, 3) = roundkeys(i-1, 3) ^ roundkeys(i, 2);
<a name="l00055"></a>00055 }
<a name="l00056"></a>00056
<a name="l00057"></a>00057 <span class="comment">/* produce the round keys */</span>
<a name="l00058"></a>00058 <span class="keywordflow">if</span> (IsForwardTransformation())
<a name="l00059"></a>00059 {
<a name="l00060"></a>00060 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i < ROUNDS; i++)
<a name="l00061"></a>00061 SquareTransform (roundkeys4(i), roundkeys4(i));
<a name="l00062"></a>00062 }
<a name="l00063"></a>00063 <span class="keywordflow">else</span>
<a name="l00064"></a>00064 {
<a name="l00065"></a>00065 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i < ROUNDS/2; i++)
<a name="l00066"></a>00066 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> j = 0; j < 4; j++)
<a name="l00067"></a>00067 std::swap(roundkeys(i, j), roundkeys(ROUNDS-i, j));
<a name="l00068"></a>00068 SquareTransform (roundkeys4(ROUNDS), roundkeys4(ROUNDS));
<a name="l00069"></a>00069 }
<a name="l00070"></a>00070 }
<a name="l00071"></a>00071
<a name="l00072"></a>00072 <span class="preprocessor">#define MSB(x) (((x) >> 24) & 0xffU) </span><span class="comment">/* most significant byte */</span>
<a name="l00073"></a>00073 <span class="preprocessor">#define SSB(x) (((x) >> 16) & 0xffU) </span><span class="comment">/* second in significance */</span>
<a name="l00074"></a>00074 <span class="preprocessor">#define TSB(x) (((x) >> 8) & 0xffU) </span><span class="comment">/* third in significance */</span>
<a name="l00075"></a>00075 <span class="preprocessor">#define LSB(x) (((x) ) & 0xffU) </span><span class="comment">/* least significant byte */</span>
<a name="l00076"></a>00076
<a name="l00077"></a>00077 <span class="preprocessor">#define squareRound(text, temp, T0, T1, T2, T3, roundkey) \</span>
<a name="l00078"></a>00078 <span class="preprocessor">{ \</span>
<a name="l00079"></a>00079 <span class="preprocessor"> temp[0] = T0[MSB (text[0])] \</span>
<a name="l00080"></a>00080 <span class="preprocessor"> ^ T1[MSB (text[1])] \</span>
<a name="l00081"></a>00081 <span class="preprocessor"> ^ T2[MSB (text[2])] \</span>
<a name="l00082"></a>00082 <span class="preprocessor"> ^ T3[MSB (text[3])] \</span>
<a name="l00083"></a>00083 <span class="preprocessor"> ^ roundkey[0]; \</span>
<a name="l00084"></a>00084 <span class="preprocessor"> temp[1] = T0[SSB (text[0])] \</span>
<a name="l00085"></a>00085 <span class="preprocessor"> ^ T1[SSB (text[1])] \</span>
<a name="l00086"></a>00086 <span class="preprocessor"> ^ T2[SSB (text[2])] \</span>
<a name="l00087"></a>00087 <span class="preprocessor"> ^ T3[SSB (text[3])] \</span>
<a name="l00088"></a>00088 <span class="preprocessor"> ^ roundkey[1]; \</span>
<a name="l00089"></a>00089 <span class="preprocessor"> temp[2] = T0[TSB (text[0])] \</span>
<a name="l00090"></a>00090 <span class="preprocessor"> ^ T1[TSB (text[1])] \</span>
<a name="l00091"></a>00091 <span class="preprocessor"> ^ T2[TSB (text[2])] \</span>
<a name="l00092"></a>00092 <span class="preprocessor"> ^ T3[TSB (text[3])] \</span>
<a name="l00093"></a>00093 <span class="preprocessor"> ^ roundkey[2]; \</span>
<a name="l00094"></a>00094 <span class="preprocessor"> temp[3] = T0[LSB (text[0])] \</span>
<a name="l00095"></a>00095 <span class="preprocessor"> ^ T1[LSB (text[1])] \</span>
<a name="l00096"></a>00096 <span class="preprocessor"> ^ T2[LSB (text[2])] \</span>
<a name="l00097"></a>00097 <span class="preprocessor"> ^ T3[LSB (text[3])] \</span>
<a name="l00098"></a>00098 <span class="preprocessor"> ^ roundkey[3]; \</span>
<a name="l00099"></a>00099 <span class="preprocessor">} </span><span class="comment">/* squareRound */</span>
<a name="l00100"></a>00100
<a name="l00101"></a>00101 <span class="preprocessor">#define squareFinal(text, temp, S, roundkey) \</span>
<a name="l00102"></a>00102 <span class="preprocessor">{ \</span>
<a name="l00103"></a>00103 <span class="preprocessor"> text[0] = ((word32) (S[MSB (temp[0])]) << 24) \</span>
<a name="l00104"></a>00104 <span class="preprocessor"> ^ ((word32) (S[MSB (temp[1])]) << 16) \</span>
<a name="l00105"></a>00105 <span class="preprocessor"> ^ ((word32) (S[MSB (temp[2])]) << 8) \</span>
<a name="l00106"></a>00106 <span class="preprocessor"> ^ (word32) (S[MSB (temp[3])]) \</span>
<a name="l00107"></a>00107 <span class="preprocessor"> ^ roundkey[0]; \</span>
<a name="l00108"></a>00108 <span class="preprocessor"> text[1] = ((word32) (S[SSB (temp[0])]) << 24) \</span>
<a name="l00109"></a>00109 <span class="preprocessor"> ^ ((word32) (S[SSB (temp[1])]) << 16) \</span>
<a name="l00110"></a>00110 <span class="preprocessor"> ^ ((word32) (S[SSB (temp[2])]) << 8) \</span>
<a name="l00111"></a>00111 <span class="preprocessor"> ^ (word32) (S[SSB (temp[3])]) \</span>
<a name="l00112"></a>00112 <span class="preprocessor"> ^ roundkey[1]; \</span>
<a name="l00113"></a>00113 <span class="preprocessor"> text[2] = ((word32) (S[TSB (temp[0])]) << 24) \</span>
<a name="l00114"></a>00114 <span class="preprocessor"> ^ ((word32) (S[TSB (temp[1])]) << 16) \</span>
<a name="l00115"></a>00115 <span class="preprocessor"> ^ ((word32) (S[TSB (temp[2])]) << 8) \</span>
<a name="l00116"></a>00116 <span class="preprocessor"> ^ (word32) (S[TSB (temp[3])]) \</span>
<a name="l00117"></a>00117 <span class="preprocessor"> ^ roundkey[2]; \</span>
<a name="l00118"></a>00118 <span class="preprocessor"> text[3] = ((word32) (S[LSB (temp[0])]) << 24) \</span>
<a name="l00119"></a>00119 <span class="preprocessor"> ^ ((word32) (S[LSB (temp[1])]) << 16) \</span>
<a name="l00120"></a>00120 <span class="preprocessor"> ^ ((word32) (S[LSB (temp[2])]) << 8) \</span>
<a name="l00121"></a>00121 <span class="preprocessor"> ^ (word32) (S[LSB (temp[3])]) \</span>
<a name="l00122"></a>00122 <span class="preprocessor"> ^ roundkey[3]; \</span>
<a name="l00123"></a>00123 <span class="preprocessor">} </span><span class="comment">/* squareFinal */</span>
<a name="l00124"></a>00124
<a name="l00125"></a>00125 <span class="keyword">typedef</span> <a class="code" href="struct_block_get_and_put.html">BlockGetAndPut<word32, BigEndian></a> <a class="code" href="struct_block_get_and_put.html">Block</a>;
<a name="l00126"></a>00126
<a name="l00127"></a>00127 <span class="keywordtype">void</span> Square::Enc::ProcessAndXorBlock(<span class="keyword">const</span> byte *inBlock, <span class="keyword">const</span> byte *xorBlock, byte *outBlock)<span class="keyword"> const</span>
<a name="l00128"></a>00128 <span class="keyword"></span>{
<a name="l00129"></a>00129 word32 text[4], temp[4];
<a name="l00130"></a>00130 Block::Get(inBlock)(text[0])(text[1])(text[2])(text[3]);
<a name="l00131"></a>00131
<a name="l00132"></a>00132 <span class="comment">/* initial key addition */</span>
<a name="l00133"></a>00133 text[0] ^= roundkeys(0, 0);
<a name="l00134"></a>00134 text[1] ^= roundkeys(0, 1);
<a name="l00135"></a>00135 text[2] ^= roundkeys(0, 2);
<a name="l00136"></a>00136 text[3] ^= roundkeys(0, 3);
<a name="l00137"></a>00137
<a name="l00138"></a>00138 <span class="comment">/* ROUNDS - 1 full rounds */</span>
<a name="l00139"></a>00139 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i=1; i+1<ROUNDS; i+=2)
<a name="l00140"></a>00140 {
<a name="l00141"></a>00141 squareRound (text, temp, Te[0], Te[1], Te[2], Te[3], roundkeys4(i));
<a name="l00142"></a>00142 squareRound (temp, text, Te[0], Te[1], Te[2], Te[3], roundkeys4(i+1));
<a name="l00143"></a>00143 }
<a name="l00144"></a>00144 squareRound (text, temp, Te[0], Te[1], Te[2], Te[3], roundkeys4(ROUNDS-1));
<a name="l00145"></a>00145
<a name="l00146"></a>00146 <span class="comment">/* last round (diffusion becomes only transposition) */</span>
<a name="l00147"></a>00147 squareFinal (text, temp, Se, roundkeys4(ROUNDS));
<a name="l00148"></a>00148
<a name="l00149"></a>00149 <a class="code" href="class_put_block.html">Block::Put</a>(xorBlock, outBlock)(text[0])(text[1])(text[2])(text[3]);
<a name="l00150"></a>00150 }
<a name="l00151"></a>00151
<a name="l00152"></a>00152 <span class="keywordtype">void</span> Square::Dec::ProcessAndXorBlock(<span class="keyword">const</span> byte *inBlock, <span class="keyword">const</span> byte *xorBlock, byte *outBlock)<span class="keyword"> const</span>
<a name="l00153"></a>00153 <span class="keyword"></span>{
<a name="l00154"></a>00154 word32 text[4], temp[4];
<a name="l00155"></a>00155 Block::Get(inBlock)(text[0])(text[1])(text[2])(text[3]);
<a name="l00156"></a>00156
<a name="l00157"></a>00157 <span class="comment">/* initial key addition */</span>
<a name="l00158"></a>00158 text[0] ^= roundkeys(0, 0);
<a name="l00159"></a>00159 text[1] ^= roundkeys(0, 1);
<a name="l00160"></a>00160 text[2] ^= roundkeys(0, 2);
<a name="l00161"></a>00161 text[3] ^= roundkeys(0, 3);
<a name="l00162"></a>00162
<a name="l00163"></a>00163 <span class="comment">/* ROUNDS - 1 full rounds */</span>
<a name="l00164"></a>00164 <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i=1; i+1<ROUNDS; i+=2)
<a name="l00165"></a>00165 {
<a name="l00166"></a>00166 squareRound (text, temp, Td[0], Td[1], Td[2], Td[3], roundkeys4(i));
<a name="l00167"></a>00167 squareRound (temp, text, Td[0], Td[1], Td[2], Td[3], roundkeys4(i+1));
<a name="l00168"></a>00168 }
<a name="l00169"></a>00169 squareRound (text, temp, Td[0], Td[1], Td[2], Td[3], roundkeys4(ROUNDS-1));
<a name="l00170"></a>00170
<a name="l00171"></a>00171 <span class="comment">/* last round (diffusion becomes only transposition) */</span>
<a name="l00172"></a>00172 squareFinal (text, temp, Sd, roundkeys4(ROUNDS));
<a name="l00173"></a>00173
<a name="l00174"></a>00174 <a class="code" href="class_put_block.html">Block::Put</a>(xorBlock, outBlock)(text[0])(text[1])(text[2])(text[3]);
<a name="l00175"></a>00175 }
<a name="l00176"></a>00176
<a name="l00177"></a>00177 NAMESPACE_END
</pre></div></div>
</div>
<hr class="footer"/><address class="footer"><small>Generated on Sun Oct 16 2011 for Crypto++ by 
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.7.4 </small></address>
</body>
</html>
