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Crypto++是一个非常强大的密码学库,主要是功能全

00169         Decode(dec, length);
00170         dec.<a class="code" href="class_b_e_r_general_decoder.html#_b_e_r_set_decodera9">MessageEnd</a>();
00171 }
00172 
<a name="l00173"></a><a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_2">00173</a> <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_2">PolynomialMod2::WordCount</a>()<span class="keyword"> const</span>
00174 <span class="keyword"></span>{
00175         <span class="keywordflow">return</span> CountWords(reg, reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>());
00176 }
00177 
<a name="l00178"></a><a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_1">00178</a> <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_1">PolynomialMod2::ByteCount</a>()<span class="keyword"> const</span>
00179 <span class="keyword"></span>{
00180         <span class="keywordtype">unsigned</span> wordCount = <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_2">WordCount</a>();
00181         <span class="keywordflow">if</span> (wordCount)
00182                 <span class="keywordflow">return</span> (wordCount-1)*WORD_SIZE + BytePrecision(reg[wordCount-1]);
00183         <span class="keywordflow">else</span>
00184                 <span class="keywordflow">return</span> 0;
00185 }
00186 
<a name="l00187"></a><a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_0">00187</a> <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_0">PolynomialMod2::BitCount</a>()<span class="keyword"> const</span>
00188 <span class="keyword"></span>{
00189         <span class="keywordtype">unsigned</span> wordCount = <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_2">WordCount</a>();
00190         <span class="keywordflow">if</span> (wordCount)
00191                 <span class="keywordflow">return</span> (wordCount-1)*WORD_BITS + BitPrecision(reg[wordCount-1]);
00192         <span class="keywordflow">else</span>
00193                 <span class="keywordflow">return</span> 0;
00194 }
00195 
<a name="l00196"></a><a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z31_0">00196</a> <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z31_0">PolynomialMod2::Parity</a>()<span class="keyword"> const</span>
00197 <span class="keyword"></span>{
00198         <span class="keywordtype">unsigned</span> i;
00199         word temp=0;
00200         <span class="keywordflow">for</span> (i=0; i&lt;reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>(); i++)
00201                 temp ^= reg[i];
00202         <span class="keywordflow">return</span> CryptoPP::Parity(temp);
00203 }
00204 
00205 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a>&amp; PolynomialMod2::operator=(<span class="keyword">const</span> <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a>&amp; t)
00206 {
00207         reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta15">Assign</a>(t.reg);
00208         <span class="keywordflow">return</span> *<span class="keyword">this</span>;
00209 }
00210 
00211 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a>&amp; PolynomialMod2::operator^=(<span class="keyword">const</span> <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a>&amp; t)
00212 {
00213         reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta22">CleanGrow</a>(t.reg.size());
00214         XorWords(reg, t.reg, t.reg.size());
00215         <span class="keywordflow">return</span> *<span class="keyword">this</span>;
00216 }
00217 
00218 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> PolynomialMod2::Xor(<span class="keyword">const</span> <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> &amp;b)<span class="keyword"> const</span>
00219 <span class="keyword"></span>{
00220         <span class="keywordflow">if</span> (b.reg.size() &gt;= reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>())
00221         {
00222                 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> result((word)0, b.reg.size()*WORD_BITS);
00223                 XorWords(result.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>, reg, b.reg, reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>());
00224                 CopyWords(result.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>+reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>(), b.reg+reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>(), b.reg.size()-reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>());
00225                 <span class="keywordflow">return</span> result;
00226         }
00227         <span class="keywordflow">else</span>
00228         {
00229                 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> result((word)0, reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>()*WORD_BITS);
00230                 XorWords(result.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>, reg, b.reg, b.reg.size());
00231                 CopyWords(result.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>+b.reg.size(), reg+b.reg.size(), reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>()-b.reg.size());
00232                 <span class="keywordflow">return</span> result;
00233         }
00234 }
00235 
00236 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> PolynomialMod2::And(<span class="keyword">const</span> <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> &amp;b)<span class="keyword"> const</span>
00237 <span class="keyword"></span>{
00238         <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> result((word)0, WORD_BITS*STDMIN(reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>(), b.reg.size()));
00239         AndWords(result.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>, reg, b.reg, result.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>());
00240         <span class="keywordflow">return</span> result;
00241 }
00242 
00243 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> PolynomialMod2::Times(<span class="keyword">const</span> <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> &amp;b)<span class="keyword"> const</span>
00244 <span class="keyword"></span>{
00245         <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> result((word)0, <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_0">BitCount</a>() + b.BitCount());
00246 
00247         <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i=b.Degree(); i&gt;=0; i--)
00248         {
00249                 result &lt;&lt;= 1;
00250                 <span class="keywordflow">if</span> (b[i])
00251                         XorWords(result.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>, reg, reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>());
00252         }
00253         <span class="keywordflow">return</span> result;
00254 }
00255 
00256 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> PolynomialMod2::Squared()<span class="keyword"> const</span>
00257 <span class="keyword"></span>{
00258         <span class="keyword">static</span> <span class="keyword">const</span> word map[16] = {0, 1, 4, 5, 16, 17, 20, 21, 64, 65, 68, 69, 80, 81, 84, 85};
00259 
00260         <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> result((word)0, 2*reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>()*WORD_BITS);
00261 
00262         <span class="keywordflow">for</span> (<span class="keywordtype">unsigned</span> i=0; i&lt;reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>(); i++)
00263         {
00264                 <span class="keywordtype">unsigned</span> j;
00265 
00266                 <span class="keywordflow">for</span> (j=0; j&lt;WORD_BITS; j+=8)
00267                         result.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>[2*i] |= map[(reg[i] &gt;&gt; (j/2)) % 16] &lt;&lt; j;
00268 
00269                 <span class="keywordflow">for</span> (j=0; j&lt;WORD_BITS; j+=8)
00270                         result.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>[2*i+1] |= map[(reg[i] &gt;&gt; (j/2 + WORD_BITS/2)) % 16] &lt;&lt; j;
00271         }
00272 
00273         <span class="keywordflow">return</span> result;
00274 }
00275 
<a name="l00276"></a><a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z31_8">00276</a> <span class="keywordtype">void</span> <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z31_8">PolynomialMod2::Divide</a>(<a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> &amp;remainder, <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> &amp;quotient,
00277                                    <span class="keyword">const</span> <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> &amp;dividend, <span class="keyword">const</span> <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> &amp;divisor)
00278 {
00279         <span class="keywordflow">if</span> (!divisor)
00280                 <span class="keywordflow">throw</span> <a class="code" href="class_polynomial_mod2_1_1_divide_by_zero.html">PolynomialMod2::DivideByZero</a>();
00281 
00282         <span class="keywordtype">int</span> degree = divisor.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_5">Degree</a>();
00283         remainder.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>.<a class="code" href="class_sec_block.html#_sec_block_with_hinta20">CleanNew</a>(BitsToWords(degree+1));
00284         <span class="keywordflow">if</span> (dividend.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_0">BitCount</a>() &gt;= divisor.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_0">BitCount</a>())
00285                 quotient.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>.<a class="code" href="class_sec_block.html#_sec_block_with_hinta20">CleanNew</a>(BitsToWords(dividend.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_0">BitCount</a>() - divisor.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_0">BitCount</a>() + 1));
00286         <span class="keywordflow">else</span>
00287                 quotient.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>.<a class="code" href="class_sec_block.html#_sec_block_with_hinta20">CleanNew</a>(0);
00288 
00289         <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i=dividend.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z23_5">Degree</a>(); i&gt;=0; i--)
00290         {
00291                 remainder &lt;&lt;= 1;
00292                 remainder.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2r0">reg</a>[0] |= dividend[i];
00293                 <span class="keywordflow">if</span> (remainder[degree])
00294                 {
00295                         remainder -= divisor;
00296                         quotient.<a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z25_11">SetBit</a>(i);
00297                 }
00298         }
00299 }
00300 
00301 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> PolynomialMod2::DividedBy(<span class="keyword">const</span> <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> &amp;b)<span class="keyword"> const</span>
00302 <span class="keyword"></span>{
00303         <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> remainder, quotient;
00304         <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z31_8">PolynomialMod2::Divide</a>(remainder, quotient, *<span class="keyword">this</span>, b);
00305         <span class="keywordflow">return</span> quotient;
00306 }
00307 
00308 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> PolynomialMod2::Modulo(<span class="keyword">const</span> <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> &amp;b)<span class="keyword"> const</span>
00309 <span class="keyword"></span>{
00310         <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a> remainder, quotient;
00311         <a class="code" href="class_polynomial_mod2.html#_polynomial_mod2z31_8">PolynomialMod2::Divide</a>(remainder, quotient, *<span class="keyword">this</span>, b);
00312         <span class="keywordflow">return</span> remainder;
00313 }
00314 
00315 <a class="code" href="class_polynomial_mod2.html">PolynomialMod2</a>&amp; PolynomialMod2::operator&lt;&lt;=(<span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> n)
00316 {
00317         <span class="keywordflow">if</span> (!reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>())
00318                 <span class="keywordflow">return</span> *<span class="keyword">this</span>;
00319 
00320         <span class="keywordtype">int</span> i;
00321         word u;
00322         word carry=0;
00323         word *r=reg;
00324 
00325         <span class="keywordflow">if</span> (n==1)       <span class="comment">// special case code for most frequent case</span>
00326         {
00327                 i = reg.<a class="code" href="class_sec_block.html#_sec_block_with_hinta13">size</a>();
00328                 <span class="keywordflow">while</span> (i--)
00329                 {
00330                         u = *r;
00331                         *r = (u &lt;&lt; 1) | carry;
00332                         carry = u &gt;&gt; (WORD_BITS-1);
00333                         r++;
00334                 }
00335 
00336                 <span class="keywordflow">if</span> (carry)
00337                 {
00338                         reg.Grow(reg.size()+1);
00339                         reg[reg.size()-1] = carry;
00340                 }
00341 
00342                 <span class="keywordflow">return</span> *<span class="keyword">this</span>;
00343         }