<!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++: iterhash.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 1.6.1 --> <div class="navigation" id="top"> <div class="tabs"> <ul> <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 class="tabs"> <ul> <li><a href="files.html"><span>File List</span></a></li> <li><a href="globals.html"><span>File Members</span></a></li> </ul> </div> <h1>iterhash.cpp</h1><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">// iterhash.cpp - written and placed in the public domain by Wei Dai</span> <a name="l00002"></a>00002 <a name="l00003"></a>00003 <span class="preprocessor">#ifndef __GNUC__</span> <a name="l00004"></a>00004 <span class="preprocessor"></span><span class="preprocessor">#define CRYPTOPP_MANUALLY_INSTANTIATE_TEMPLATES</span> <a name="l00005"></a>00005 <span class="preprocessor"></span><span class="preprocessor">#endif</span> <a name="l00006"></a>00006 <span class="preprocessor"></span> <a name="l00007"></a>00007 <span class="preprocessor">#include "iterhash.h"</span> <a name="l00008"></a>00008 <span class="preprocessor">#include "misc.h"</span> <a name="l00009"></a>00009 <a name="l00010"></a>00010 NAMESPACE_BEGIN(CryptoPP) <a name="l00011"></a>00011 <a name="l00012"></a>00012 template <class T, class <a class="code" href="class_b_a_s_e.html">BASE</a>> <span class="keywordtype">void</span> <a class="code" href="class_iterated_hash_base.html" title="_">IteratedHashBase</a><T, <a class="code" href="class_b_a_s_e.html">BASE</a>>::Update(const byte *input, <span class="keywordtype">size_t</span> len) <a name="l00013"></a>00013 { <a name="l00014"></a>00014 HashWordType oldCountLo = m_countLo, oldCountHi = m_countHi; <a name="l00015"></a>00015 <span class="keywordflow">if</span> ((m_countLo = oldCountLo + HashWordType(len)) < oldCountLo) <a name="l00016"></a>00016 m_countHi++; <span class="comment">// carry from low to high</span> <a name="l00017"></a>00017 m_countHi += (HashWordType)SafeRightShift<8*<span class="keyword">sizeof</span>(HashWordType)>(len); <a name="l00018"></a>00018 <span class="keywordflow">if</span> (m_countHi < oldCountHi || SafeRightShift<2*8*<span class="keyword">sizeof</span>(HashWordType)>(len) != 0) <a name="l00019"></a>00019 <span class="keywordflow">throw</span> <a class="code" href="class_hash_input_too_long.html" title="exception thrown when trying to hash more data than is allowed by a hash function...">HashInputTooLong</a>(this->AlgorithmName()); <a name="l00020"></a>00020 <a name="l00021"></a>00021 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> blockSize = this->BlockSize(); <a name="l00022"></a>00022 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> num = ModPowerOf2(oldCountLo, blockSize); <a name="l00023"></a>00023 T* dataBuf = this->DataBuf(); <a name="l00024"></a>00024 byte* data = (byte *)dataBuf; <a name="l00025"></a>00025 <a name="l00026"></a>00026 <span class="keywordflow">if</span> (num != 0) <span class="comment">// process left over data</span> <a name="l00027"></a>00027 { <a name="l00028"></a>00028 <span class="keywordflow">if</span> (num+len >= blockSize) <a name="l00029"></a>00029 { <a name="l00030"></a>00030 memcpy(data+num, input, blockSize-num); <a name="l00031"></a>00031 HashBlock(dataBuf); <a name="l00032"></a>00032 input += (blockSize-num); <a name="l00033"></a>00033 len -= (blockSize-num); <a name="l00034"></a>00034 num = 0; <a name="l00035"></a>00035 <span class="comment">// drop through and do the rest</span> <a name="l00036"></a>00036 } <a name="l00037"></a>00037 <span class="keywordflow">else</span> <a name="l00038"></a>00038 { <a name="l00039"></a>00039 memcpy(data+num, input, len); <a name="l00040"></a>00040 <span class="keywordflow">return</span>; <a name="l00041"></a>00041 } <a name="l00042"></a>00042 } <a name="l00043"></a>00043 <a name="l00044"></a>00044 <span class="comment">// now process the input data in blocks of blockSize bytes and save the leftovers to m_data</span> <a name="l00045"></a>00045 <span class="keywordflow">if</span> (len >= blockSize) <a name="l00046"></a>00046 { <a name="l00047"></a>00047 <span class="keywordflow">if</span> (input == data) <a name="l00048"></a>00048 { <a name="l00049"></a>00049 assert(len == blockSize); <a name="l00050"></a>00050 HashBlock(dataBuf); <a name="l00051"></a>00051 <span class="keywordflow">return</span>; <a name="l00052"></a>00052 } <a name="l00053"></a>00053 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (IsAligned<T>(input)) <a name="l00054"></a>00054 { <a name="l00055"></a>00055 <span class="keywordtype">size_t</span> leftOver = HashMultipleBlocks((T *)input, len); <a name="l00056"></a>00056 input += (len - leftOver); <a name="l00057"></a>00057 len = leftOver; <a name="l00058"></a>00058 } <a name="l00059"></a>00059 <span class="keywordflow">else</span> <a name="l00060"></a>00060 <span class="keywordflow">do</span> <a name="l00061"></a>00061 { <span class="comment">// copy input first if it's not aligned correctly</span> <a name="l00062"></a>00062 memcpy(data, input, blockSize); <a name="l00063"></a>00063 HashBlock(dataBuf); <a name="l00064"></a>00064 input+=blockSize; <a name="l00065"></a>00065 len-=blockSize; <a name="l00066"></a>00066 } <span class="keywordflow">while</span> (len >= blockSize); <a name="l00067"></a>00067 } <a name="l00068"></a>00068 <a name="l00069"></a>00069 memcpy(data, input, len); <a name="l00070"></a>00070 } <a name="l00071"></a>00071 <a name="l00072"></a>00072 <span class="keyword">template</span> <<span class="keyword">class</span> T, <span class="keyword">class</span> BASE> byte * <a class="code" href="class_iterated_hash_base.html" title="_">IteratedHashBase<T, BASE>::CreateUpdateSpace</a>(<span class="keywordtype">size_t</span> &size) <a name="l00073"></a>00073 { <a name="l00074"></a>00074 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> blockSize = this->BlockSize(); <a name="l00075"></a>00075 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> num = ModPowerOf2(m_countLo, blockSize); <a name="l00076"></a>00076 size = blockSize - num; <a name="l00077"></a>00077 <span class="keywordflow">return</span> (byte *)DataBuf() + num; <a name="l00078"></a>00078 } <a name="l00079"></a>00079 <a name="l00080"></a>00080 <span class="keyword">template</span> <<span class="keyword">class</span> T, <span class="keyword">class</span> BASE> <span class="keywordtype">size_t</span> <a class="code" href="class_iterated_hash_base.html" title="_">IteratedHashBase<T, BASE>::HashMultipleBlocks</a>(<span class="keyword">const</span> T *input, <span class="keywordtype">size_t</span> length) <a name="l00081"></a>00081 { <a name="l00082"></a>00082 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> blockSize = this->BlockSize(); <a name="l00083"></a>00083 <span class="keywordtype">bool</span> noReverse = NativeByteOrderIs(this->GetByteOrder()); <a name="l00084"></a>00084 T* dataBuf = this->DataBuf(); <a name="l00085"></a>00085 <span class="keywordflow">do</span> <a name="l00086"></a>00086 { <a name="l00087"></a>00087 <span class="keywordflow">if</span> (noReverse) <a name="l00088"></a>00088 this->HashEndianCorrectedBlock(input); <a name="l00089"></a>00089 <span class="keywordflow">else</span> <a name="l00090"></a>00090 { <a name="l00091"></a>00091 ByteReverse(dataBuf, input, this->BlockSize()); <a name="l00092"></a>00092 this->HashEndianCorrectedBlock(dataBuf); <a name="l00093"></a>00093 } <a name="l00094"></a>00094 <a name="l00095"></a>00095 input += blockSize/<span class="keyword">sizeof</span>(T); <a name="l00096"></a>00096 length -= blockSize; <a name="l00097"></a>00097 } <a name="l00098"></a>00098 <span class="keywordflow">while</span> (length >= blockSize); <a name="l00099"></a>00099 <span class="keywordflow">return</span> length; <a name="l00100"></a>00100 } <a name="l00101"></a>00101 <a name="l00102"></a>00102 <span class="keyword">template</span> <<span class="keyword">class</span> T, <span class="keyword">class</span> BASE> <span class="keywordtype">void</span> <a class="code" href="class_iterated_hash_base.html" title="_">IteratedHashBase<T, BASE>::PadLastBlock</a>(<span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> lastBlockSize, byte padFirst) <a name="l00103"></a>00103 { <a name="l00104"></a>00104 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> blockSize = this->BlockSize(); <a name="l00105"></a>00105 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> num = ModPowerOf2(m_countLo, blockSize); <a name="l00106"></a>00106 T* dataBuf = this->DataBuf(); <a name="l00107"></a>00107 byte* data = (byte *)dataBuf; <a name="l00108"></a>00108 data[num++] = padFirst; <a name="l00109"></a>00109 <span class="keywordflow">if</span> (num <= lastBlockSize) <a name="l00110"></a>00110 memset(data+num, 0, lastBlockSize-num); <a name="l00111"></a>00111 <span class="keywordflow">else</span> <a name="l00112"></a>00112 { <a name="l00113"></a>00113 memset(data+num, 0, blockSize-num); <a name="l00114"></a>00114 HashBlock(dataBuf); <a name="l00115"></a>00115 memset(data, 0, lastBlockSize); <a name="l00116"></a>00116 } <a name="l00117"></a>00117 } <a name="l00118"></a>00118 <a name="l00119"></a>00119 <span class="keyword">template</span> <<span class="keyword">class</span> T, <span class="keyword">class</span> BASE> <span class="keywordtype">void</span> <a class="code" href="class_iterated_hash_base.html" title="_">IteratedHashBase<T, BASE>::Restart</a>() <a name="l00120"></a>00120 { <a name="l00121"></a>00121 m_countLo = m_countHi = 0; <a name="l00122"></a>00122 Init(); <a name="l00123"></a>00123 } <a name="l00124"></a>00124 <a name="l00125"></a>00125 <span class="keyword">template</span> <<span class="keyword">class</span> T, <span class="keyword">class</span> BASE> <span class="keywordtype">void</span> <a class="code" href="class_iterated_hash_base.html" title="_">IteratedHashBase<T, BASE>::TruncatedFinal</a>(byte *digest, <span class="keywordtype">size_t</span> size) <a name="l00126"></a>00126 { <a name="l00127"></a>00127 this->ThrowIfInvalidTruncatedSize(size); <a name="l00128"></a>00128 <a name="l00129"></a>00129 T* dataBuf = this->DataBuf(); <a name="l00130"></a>00130 T* stateBuf = this->StateBuf(); <a name="l00131"></a>00131 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> blockSize = this->BlockSize(); <a name="l00132"></a>00132 ByteOrder order = this->GetByteOrder(); <a name="l00133"></a>00133 <a name="l00134"></a>00134 PadLastBlock(blockSize - 2*<span class="keyword">sizeof</span>(HashWordType)); <a name="l00135"></a>00135 dataBuf[blockSize/<span class="keyword">sizeof</span>(T)-2+order] = ConditionalByteReverse(order, this->GetBitCountLo()); <a name="l00136"></a>00136 dataBuf[blockSize/<span class="keyword">sizeof</span>(T)-1-order] = ConditionalByteReverse(order, this->GetBitCountHi()); <a name="l00137"></a>00137 <a name="l00138"></a>00138 HashBlock(dataBuf); <a name="l00139"></a>00139 <a name="l00140"></a>00140 <span class="keywordflow">if</span> (IsAligned<HashWordType>(digest) && size%<span class="keyword">sizeof</span>(HashWordType)==0) <a name="l00141"></a>00141 ConditionalByteReverse<HashWordType>(order, (HashWordType *)digest, stateBuf, size); <a name="l00142"></a>00142 <span class="keywordflow">else</span> <a name="l00143"></a>00143 { <a name="l00144"></a>00144 ConditionalByteReverse<HashWordType>(order, stateBuf, stateBuf, this->DigestSize()); <a name="l00145"></a>00145 memcpy(digest, stateBuf, size); <a name="l00146"></a>00146 } <a name="l00147"></a>00147 <a name="l00148"></a>00148 this->Restart(); <span class="comment">// reinit for next use</span> <a name="l00149"></a>00149 } <a name="l00150"></a>00150 <a name="l00151"></a>00151 <span class="preprocessor">#ifdef __GNUC__</span> <a name="l00152"></a>00152 <span class="preprocessor"></span> <span class="keyword">template</span> <span class="keyword">class </span><a class="code" href="class_iterated_hash_base.html">IteratedHashBase<word64, HashTransformation></a>; <a name="l00153"></a>00153 <span class="keyword">template</span> <span class="keyword">class </span><a class="code" href="class_iterated_hash_base.html">IteratedHashBase<word64, MessageAuthenticationCode></a>; <a name="l00154"></a>00154 <a name="l00155"></a>00155 <span class="keyword">template</span> <span class="keyword">class </span><a class="code" href="class_iterated_hash_base.html">IteratedHashBase<word32, HashTransformation></a>; <a name="l00156"></a>00156 <span class="keyword">template</span> <span class="keyword">class </span><a class="code" href="class_iterated_hash_base.html">IteratedHashBase<word32, MessageAuthenticationCode></a>; <a name="l00157"></a>00157 <span class="preprocessor">#endif</span> <a name="l00158"></a>00158 <span class="preprocessor"></span> <a name="l00159"></a>00159 NAMESPACE_END </pre></div></div> <hr size="1"/><address style="text-align: right;"><small>Generated on 9 Dec 2009 for Crypto++ by <a href="http://www.doxygen.org/index.html"> <img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.6.1 </small></address> </body> </html>