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<h1>ec2n.cpp</h1><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">// ec2n.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">#include "pch.h"</span>
<a name="l00004"></a>00004
<a name="l00005"></a>00005 <span class="preprocessor">#ifndef CRYPTOPP_IMPORTS</span>
<a name="l00006"></a>00006 <span class="preprocessor"></span>
<a name="l00007"></a>00007 <span class="preprocessor">#include "ec2n.h"</span>
<a name="l00008"></a>00008 <span class="preprocessor">#include "asn.h"</span>
<a name="l00009"></a>00009
<a name="l00010"></a>00010 <span class="preprocessor">#include "algebra.cpp"</span>
<a name="l00011"></a>00011 <span class="preprocessor">#include "eprecomp.cpp"</span>
<a name="l00012"></a>00012
<a name="l00013"></a>00013 NAMESPACE_BEGIN(CryptoPP)
<a name="l00014"></a>00014
<a name="l00015"></a>00015 <a class="code" href="class_e_c2_n.html" title="Elliptic Curve over GF(2^n).">EC2N</a>::<a class="code" href="class_e_c2_n.html" title="Elliptic Curve over GF(2^n).">EC2N</a>(<a class="code" href="class_buffered_transformation.html" title="interface for buffered transformations">BufferedTransformation</a> &bt)
<a name="l00016"></a>00016 : m_field(BERDecodeGF2NP(bt))
<a name="l00017"></a>00017 {
<a name="l00018"></a>00018 <a class="code" href="class_b_e_r_sequence_decoder.html" title="BER Sequence Decoder.">BERSequenceDecoder</a> seq(bt);
<a name="l00019"></a>00019 m_field->BERDecodeElement(seq, m_a);
<a name="l00020"></a>00020 m_field->BERDecodeElement(seq, m_b);
<a name="l00021"></a>00021 <span class="comment">// skip optional seed</span>
<a name="l00022"></a>00022 <span class="keywordflow">if</span> (!seq.EndReached())
<a name="l00023"></a>00023 {
<a name="l00024"></a>00024 <a class="code" href="class_sec_block.html" title="a block of memory allocated using A">SecByteBlock</a> seed;
<a name="l00025"></a>00025 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> unused;
<a name="l00026"></a>00026 BERDecodeBitString(seq, seed, unused);
<a name="l00027"></a>00027 }
<a name="l00028"></a>00028 seq.MessageEnd();
<a name="l00029"></a>00029 }
<a name="l00030"></a>00030
<a name="l00031"></a>00031 <span class="keywordtype">void</span> EC2N::DEREncode(<a class="code" href="class_buffered_transformation.html" title="interface for buffered transformations">BufferedTransformation</a> &bt)<span class="keyword"> const</span>
<a name="l00032"></a>00032 <span class="keyword"></span>{
<a name="l00033"></a>00033 m_field->DEREncode(bt);
<a name="l00034"></a>00034 <a class="code" href="class_d_e_r_sequence_encoder.html" title="DER Sequence Encoder.">DERSequenceEncoder</a> seq(bt);
<a name="l00035"></a>00035 m_field->DEREncodeElement(seq, m_a);
<a name="l00036"></a>00036 m_field->DEREncodeElement(seq, m_b);
<a name="l00037"></a>00037 seq.MessageEnd();
<a name="l00038"></a>00038 }
<a name="l00039"></a>00039
<a name="l00040"></a>00040 <span class="keywordtype">bool</span> EC2N::DecodePoint(<a class="code" href="struct_e_c2_n_point.html" title="Elliptic Curve Point.">EC2N::Point</a> &P, <span class="keyword">const</span> byte *encodedPoint, <span class="keywordtype">size_t</span> encodedPointLen)<span class="keyword"> const</span>
<a name="l00041"></a>00041 <span class="keyword"></span>{
<a name="l00042"></a>00042 <a class="code" href="class_string_store.html" title="string-based implementation of Store interface">StringStore</a> store(encodedPoint, encodedPointLen);
<a name="l00043"></a>00043 <span class="keywordflow">return</span> DecodePoint(P, store, encodedPointLen);
<a name="l00044"></a>00044 }
<a name="l00045"></a>00045
<a name="l00046"></a>00046 <span class="keywordtype">bool</span> EC2N::DecodePoint(<a class="code" href="struct_e_c2_n_point.html" title="Elliptic Curve Point.">EC2N::Point</a> &P, <a class="code" href="class_buffered_transformation.html" title="interface for buffered transformations">BufferedTransformation</a> &bt, <span class="keywordtype">size_t</span> encodedPointLen)<span class="keyword"> const</span>
<a name="l00047"></a>00047 <span class="keyword"></span>{
<a name="l00048"></a>00048 byte type;
<a name="l00049"></a>00049 <span class="keywordflow">if</span> (encodedPointLen < 1 || !bt.<a class="code" href="class_buffered_transformation.html#a9e1ad913c8fe697d269f408a7d5928fc" title="try to retrieve a single byte">Get</a>(type))
<a name="l00050"></a>00050 <span class="keywordflow">return</span> <span class="keyword">false</span>;
<a name="l00051"></a>00051
<a name="l00052"></a>00052 <span class="keywordflow">switch</span> (type)
<a name="l00053"></a>00053 {
<a name="l00054"></a>00054 <span class="keywordflow">case</span> 0:
<a name="l00055"></a>00055 P.identity = <span class="keyword">true</span>;
<a name="l00056"></a>00056 <span class="keywordflow">return</span> <span class="keyword">true</span>;
<a name="l00057"></a>00057 <span class="keywordflow">case</span> 2:
<a name="l00058"></a>00058 <span class="keywordflow">case</span> 3:
<a name="l00059"></a>00059 {
<a name="l00060"></a>00060 <span class="keywordflow">if</span> (encodedPointLen != EncodedPointSize(<span class="keyword">true</span>))
<a name="l00061"></a>00061 <span class="keywordflow">return</span> <span class="keyword">false</span>;
<a name="l00062"></a>00062
<a name="l00063"></a>00063 P.identity = <span class="keyword">false</span>;
<a name="l00064"></a>00064 P.x.Decode(bt, m_field->MaxElementByteLength());
<a name="l00065"></a>00065
<a name="l00066"></a>00066 <span class="keywordflow">if</span> (P.x.IsZero())
<a name="l00067"></a>00067 {
<a name="l00068"></a>00068 P.y = m_field->SquareRoot(m_b);
<a name="l00069"></a>00069 <span class="keywordflow">return</span> <span class="keyword">true</span>;
<a name="l00070"></a>00070 }
<a name="l00071"></a>00071
<a name="l00072"></a>00072 FieldElement z = m_field->Square(P.x);
<a name="l00073"></a>00073 assert(P.x == m_field->SquareRoot(z));
<a name="l00074"></a>00074 P.y = m_field->Divide(m_field->Add(m_field->Multiply(z, m_field->Add(P.x, m_a)), m_b), z);
<a name="l00075"></a>00075 assert(P.x == m_field->Subtract(m_field->Divide(m_field->Subtract(m_field->Multiply(P.y, z), m_b), z), m_a));
<a name="l00076"></a>00076 z = m_field->SolveQuadraticEquation(P.y);
<a name="l00077"></a>00077 assert(m_field->Add(m_field->Square(z), z) == P.y);
<a name="l00078"></a>00078 z.SetCoefficient(0, type & 1);
<a name="l00079"></a>00079
<a name="l00080"></a>00080 P.y = m_field->Multiply(z, P.x);
<a name="l00081"></a>00081 <span class="keywordflow">return</span> <span class="keyword">true</span>;
<a name="l00082"></a>00082 }
<a name="l00083"></a>00083 <span class="keywordflow">case</span> 4:
<a name="l00084"></a>00084 {
<a name="l00085"></a>00085 <span class="keywordflow">if</span> (encodedPointLen != EncodedPointSize(<span class="keyword">false</span>))
<a name="l00086"></a>00086 <span class="keywordflow">return</span> <span class="keyword">false</span>;
<a name="l00087"></a>00087
<a name="l00088"></a>00088 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> len = m_field->MaxElementByteLength();
<a name="l00089"></a>00089 P.identity = <span class="keyword">false</span>;
<a name="l00090"></a>00090 P.x.Decode(bt, len);
<a name="l00091"></a>00091 P.y.Decode(bt, len);
<a name="l00092"></a>00092 <span class="keywordflow">return</span> <span class="keyword">true</span>;
<a name="l00093"></a>00093 }
<a name="l00094"></a>00094 <span class="keywordflow">default</span>:
<a name="l00095"></a>00095 <span class="keywordflow">return</span> <span class="keyword">false</span>;
<a name="l00096"></a>00096 }
<a name="l00097"></a>00097 }
<a name="l00098"></a>00098
<a name="l00099"></a>00099 <span class="keywordtype">void</span> EC2N::EncodePoint(<a class="code" href="class_buffered_transformation.html" title="interface for buffered transformations">BufferedTransformation</a> &bt, <span class="keyword">const</span> Point &P, <span class="keywordtype">bool</span> compressed)<span class="keyword"> const</span>
<a name="l00100"></a>00100 <span class="keyword"></span>{
<a name="l00101"></a>00101 <span class="keywordflow">if</span> (P.identity)
<a name="l00102"></a>00102 <a class="code" href="class_null_store.html" title="empty store">NullStore</a>().TransferTo(bt, EncodedPointSize(compressed));
<a name="l00103"></a>00103 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (compressed)
<a name="l00104"></a>00104 {
<a name="l00105"></a>00105 bt.<a class="code" href="class_buffered_transformation.html#ae70658b0d271f8e114ac6c3cc9774ede" title="input a byte for processing">Put</a>(2 + (!P.x ? 0 : m_field->Divide(P.y, P.x).GetBit(0)));
<a name="l00106"></a>00106 P.x.Encode(bt, m_field->MaxElementByteLength());
<a name="l00107"></a>00107 }
<a name="l00108"></a>00108 <span class="keywordflow">else</span>
<a name="l00109"></a>00109 {
<a name="l00110"></a>00110 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> len = m_field->MaxElementByteLength();
<a name="l00111"></a>00111 bt.<a class="code" href="class_buffered_transformation.html#ae70658b0d271f8e114ac6c3cc9774ede" title="input a byte for processing">Put</a>(4); <span class="comment">// uncompressed</span>
<a name="l00112"></a>00112 P.x.Encode(bt, len);
<a name="l00113"></a>00113 P.y.Encode(bt, len);
<a name="l00114"></a>00114 }
<a name="l00115"></a>00115 }
<a name="l00116"></a>00116
<a name="l00117"></a>00117 <span class="keywordtype">void</span> EC2N::EncodePoint(byte *encodedPoint, <span class="keyword">const</span> Point &P, <span class="keywordtype">bool</span> compressed)<span class="keyword"> const</span>
<a name="l00118"></a>00118 <span class="keyword"></span>{
<a name="l00119"></a>00119 <a class="code" href="class_array_sink.html" title="Copy input to a memory buffer.">ArraySink</a> sink(encodedPoint, EncodedPointSize(compressed));
<a name="l00120"></a>00120 EncodePoint(sink, P, compressed);
<a name="l00121"></a>00121 assert(sink.TotalPutLength() == EncodedPointSize(compressed));
<a name="l00122"></a>00122 }
<a name="l00123"></a>00123
<a name="l00124"></a>00124 <a class="code" href="struct_e_c2_n_point.html" title="Elliptic Curve Point.">EC2N::Point</a> EC2N::BERDecodePoint(<a class="code" href="class_buffered_transformation.html" title="interface for buffered transformations">BufferedTransformation</a> &bt)<span class="keyword"> const</span>
<a name="l00125"></a>00125 <span class="keyword"></span>{
<a name="l00126"></a>00126 <a class="code" href="class_sec_block.html" title="a block of memory allocated using A">SecByteBlock</a> str;
<a name="l00127"></a>00127 BERDecodeOctetString(bt, str);
<a name="l00128"></a>00128 Point P;
<a name="l00129"></a>00129 <span class="keywordflow">if</span> (!DecodePoint(P, str, str.size()))
<a name="l00130"></a>00130 BERDecodeError();
<a name="l00131"></a>00131 <span class="keywordflow">return</span> P;
<a name="l00132"></a>00132 }
<a name="l00133"></a>00133
<a name="l00134"></a>00134 <span class="keywordtype">void</span> EC2N::DEREncodePoint(<a class="code" href="class_buffered_transformation.html" title="interface for buffered transformations">BufferedTransformation</a> &bt, <span class="keyword">const</span> Point &P, <span class="keywordtype">bool</span> compressed)<span class="keyword"> const</span>
<a name="l00135"></a>00135 <span class="keyword"></span>{
<a name="l00136"></a>00136 <a class="code" href="class_sec_block.html" title="a block of memory allocated using A">SecByteBlock</a> str(EncodedPointSize(compressed));
<a name="l00137"></a>00137 EncodePoint(str, P, compressed);
<a name="l00138"></a>00138 DEREncodeOctetString(bt, str);
<a name="l00139"></a>00139 }
<a name="l00140"></a>00140
<a name="l00141"></a>00141 <span class="keywordtype">bool</span> EC2N::ValidateParameters(<a class="code" href="class_random_number_generator.html" title="interface for random number generators">RandomNumberGenerator</a> &rng, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> level)<span class="keyword"> const</span>
<a name="l00142"></a>00142 <span class="keyword"></span>{
<a name="l00143"></a>00143 <span class="keywordtype">bool</span> pass = !!m_b;
<a name="l00144"></a>00144 pass = pass && m_a.CoefficientCount() <= m_field->MaxElementBitLength();
<a name="l00145"></a>00145 pass = pass && m_b.CoefficientCount() <= m_field->MaxElementBitLength();
<a name="l00146"></a>00146
<a name="l00147"></a>00147 <span class="keywordflow">if</span> (level >= 1)
<a name="l00148"></a>00148 pass = pass && m_field->GetModulus().IsIrreducible();
<a name="l00149"></a>00149
<a name="l00150"></a>00150 <span class="keywordflow">return</span> pass;
<a name="l00151"></a>00151 }
<a name="l00152"></a>00152
<a name="l00153"></a>00153 <span class="keywordtype">bool</span> EC2N::VerifyPoint(<span class="keyword">const</span> Point &P)<span class="keyword"> const</span>
<a name="l00154"></a>00154 <span class="keyword"></span>{
<a name="l00155"></a>00155 <span class="keyword">const</span> FieldElement &x = P.x, &y = P.y;
<a name="l00156"></a>00156 <span class="keywordflow">return</span> P.identity ||
<a name="l00157"></a>00157 (x.CoefficientCount() <= m_field->MaxElementBitLength()
<a name="l00158"></a>00158 && y.CoefficientCount() <= m_field->MaxElementBitLength()
<a name="l00159"></a>00159 && !(((x+m_a)*x*x+m_b-(x+y)*y)%m_field->GetModulus()));
<a name="l00160"></a>00160 }
<a name="l00161"></a>00161
<a name="l00162"></a>00162 <span class="keywordtype">bool</span> EC2N::Equal(<span class="keyword">const</span> Point &P, <span class="keyword">const</span> Point &Q)<span class="keyword"> const</span>
<a name="l00163"></a>00163 <span class="keyword"></span>{
<a name="l00164"></a>00164 <span class="keywordflow">if</span> (P.identity && Q.identity)
<a name="l00165"></a>00165 <span class="keywordflow">return</span> <span class="keyword">true</span>;
<a name="l00166"></a>00166
<a name="l00167"></a>00167 <span class="keywordflow">if</span> (P.identity && !Q.identity)
<a name="l00168"></a>00168 <span class="keywordflow">return</span> <span class="keyword">false</span>;
<a name="l00169"></a>00169
<a name="l00170"></a>00170 <span class="keywordflow">if</span> (!P.identity && Q.identity)
<a name="l00171"></a>00171 <span class="keywordflow">return</span> <span class="keyword">false</span>;
<a name="l00172"></a>00172
<a name="l00173"></a>00173 <span class="keywordflow">return</span> (m_field->Equal(P.x,Q.x) && m_field->Equal(P.y,Q.y));
<a name="l00174"></a>00174 }
<a name="l00175"></a>00175
<a name="l00176"></a>00176 <span class="keyword">const</span> <a class="code" href="struct_e_c2_n_point.html" title="Elliptic Curve Point.">EC2N::Point</a>& EC2N::Identity()<span class="keyword"> const</span>
<a name="l00177"></a>00177 <span class="keyword"></span>{
<a name="l00178"></a>00178 <span class="keywordflow">return</span> <a class="code" href="class_singleton.html">Singleton<Point></a>().Ref();
<a name="l00179"></a>00179 }
<a name="l00180"></a>00180
<a name="l00181"></a>00181 <span class="keyword">const</span> <a class="code" href="struct_e_c2_n_point.html" title="Elliptic Curve Point.">EC2N::Point</a>& EC2N::Inverse(<span class="keyword">const</span> Point &P)<span class="keyword"> const</span>
<a name="l00182"></a>00182 <span class="keyword"></span>{
<a name="l00183"></a>00183 <span class="keywordflow">if</span> (P.identity)
<a name="l00184"></a>00184 <span class="keywordflow">return</span> P;
<a name="l00185"></a>00185 <span class="keywordflow">else</span>
<a name="l00186"></a>00186 {
<a name="l00187"></a>00187 m_R.identity = <span class="keyword">false</span>;
<a name="l00188"></a>00188 m_R.y = m_field->Add(P.x, P.y);
<a name="l00189"></a>00189 m_R.x = P.x;
<a name="l00190"></a>00190 <span class="keywordflow">return</span> m_R;
<a name="l00191"></a>00191 }
<a name="l00192"></a>00192 }
<a name="l00193"></a>00193
<a name="l00194"></a>00194 <span class="keyword">const</span> <a class="code" href="struct_e_c2_n_point.html" title="Elliptic Curve Point.">EC2N::Point</a>& EC2N::Add(<span class="keyword">const</span> Point &P, <span class="keyword">const</span> Point &Q)<span class="keyword"> const</span>
<a name="l00195"></a>00195 <span class="keyword"></span>{
<a name="l00196"></a>00196 <span class="keywordflow">if</span> (P.identity) <span class="keywordflow">return</span> Q;
<a name="l00197"></a>00197 <span class="keywordflow">if</span> (Q.identity) <span class="keywordflow">return</span> P;
<a name="l00198"></a>00198 <span class="keywordflow">if</span> (Equal(P, Q)) <span class="keywordflow">return</span> Double(P);
<a name="l00199"></a>00199 <span class="keywordflow">if</span> (m_field->Equal(P.x, Q.x) && m_field->Equal(P.y, m_field->Add(Q.x, Q.y))) <span class="keywordflow">return</span> Identity();
<a name="l00200"></a>00200
<a name="l00201"></a>00201 FieldElement t = m_field->Add(P.y, Q.y);
<a name="l00202"></a>00202 t = m_field->Divide(t, m_field->Add(P.x, Q.x));
<a name="l00203"></a>00203 FieldElement x = m_field->Square(t);
<a name="l00204"></a>00204 m_field->Accumulate(x, t);
<a name="l00205"></a>00205 m_field->Accumulate(x, Q.x);
<a name="l00206"></a>00206 m_field->Accumulate(x, m_a);
<a name="l00207"></a>00207 m_R.y = m_field->Add(P.y, m_field->Multiply(t, x));
<a name="l00208"></a>00208 m_field->Accumulate(x, P.x);
<a name="l00209"></a>00209 m_field->Accumulate(m_R.y, x);
<a name="l00210"></a>00210
<a name="l00211"></a>00211 m_R.x.swap(x);
<a name="l00212"></a>00212 m_R.identity = <span class="keyword">false</span>;
<a name="l00213"></a>00213 <span class="keywordflow">return</span> m_R;
<a name="l00214"></a>00214 }
<a name="l00215"></a>00215
<a name="l00216"></a>00216 <span class="keyword">const</span> <a class="code" href="struct_e_c2_n_point.html" title="Elliptic Curve Point.">EC2N::Point</a>& EC2N::Double(<span class="keyword">const</span> Point &P)<span class="keyword"> const</span>
<a name="l00217"></a>00217 <span class="keyword"></span>{
<a name="l00218"></a>00218 <span class="keywordflow">if</span> (P.identity) <span class="keywordflow">return</span> P;
<a name="l00219"></a>00219 <span class="keywordflow">if</span> (!m_field->IsUnit(P.x)) <span class="keywordflow">return</span> Identity();
<a name="l00220"></a>00220
<a name="l00221"></a>00221 FieldElement t = m_field->Divide(P.y, P.x);
<a name="l00222"></a>00222 m_field->Accumulate(t, P.x);
<a name="l00223"></a>00223 m_R.y = m_field->Square(P.x);
<a name="l00224"></a>00224 m_R.x = m_field->Square(t);
<a name="l00225"></a>00225 m_field->Accumulate(m_R.x, t);
<a name="l00226"></a>00226 m_field->Accumulate(m_R.x, m_a);
<a name="l00227"></a>00227 m_field->Accumulate(m_R.y, m_field->Multiply(t, m_R.x));
<a name="l00228"></a>00228 m_field->Accumulate(m_R.y, m_R.x);
<a name="l00229"></a>00229
<a name="l00230"></a>00230 m_R.identity = <span class="keyword">false</span>;
<a name="l00231"></a>00231 <span class="keywordflow">return</span> m_R;
<a name="l00232"></a>00232 }
<a name="l00233"></a>00233
<a name="l00234"></a>00234 <span class="comment">// ********************************************************</span>
<a name="l00235"></a>00235
<a name="l00236"></a>00236 <span class="comment">/*</span>
<a name="l00237"></a>00237 <span class="comment">EcPrecomputation<EC2N>& EcPrecomputation<EC2N>::operator=(const EcPrecomputation<EC2N> &rhs)</span>
<a name="l00238"></a>00238 <span class="comment">{</span>
<a name="l00239"></a>00239 <span class="comment"> m_ec = rhs.m_ec;</span>
<a name="l00240"></a>00240 <span class="comment"> m_ep = rhs.m_ep;</span>
<a name="l00241"></a>00241 <span class="comment"> m_ep.m_group = m_ec.get();</span>
<a name="l00242"></a>00242 <span class="comment"> return *this;</span>
<a name="l00243"></a>00243 <span class="comment">}</span>
<a name="l00244"></a>00244 <span class="comment"></span>
<a name="l00245"></a>00245 <span class="comment">void EcPrecomputation<EC2N>::SetCurveAndBase(const EC2N &ec, const EC2N::Point &base)</span>
<a name="l00246"></a>00246 <span class="comment">{</span>
<a name="l00247"></a>00247 <span class="comment"> m_ec.reset(new EC2N(ec));</span>
<a name="l00248"></a>00248 <span class="comment"> m_ep.SetGroupAndBase(*m_ec, base);</span>
<a name="l00249"></a>00249 <span class="comment">}</span>
<a name="l00250"></a>00250 <span class="comment"></span>
<a name="l00251"></a>00251 <span class="comment">void EcPrecomputation<EC2N>::Precompute(unsigned int maxExpBits, unsigned int storage)</span>
<a name="l00252"></a>00252 <span class="comment">{</span>
<a name="l00253"></a>00253 <span class="comment"> m_ep.Precompute(maxExpBits, storage);</span>
<a name="l00254"></a>00254 <span class="comment">}</span>
<a name="l00255"></a>00255 <span class="comment"></span>
<a name="l00256"></a>00256 <span class="comment">void EcPrecomputation<EC2N>::Load(BufferedTransformation &bt)</span>
<a name="l00257"></a>00257 <span class="comment">{</span>
<a name="l00258"></a>00258 <span class="comment"> BERSequenceDecoder seq(bt);</span>
<a name="l00259"></a>00259 <span class="comment"> word32 version;</span>
<a name="l00260"></a>00260 <span class="comment"> BERDecodeUnsigned<word32>(seq, version, INTEGER, 1, 1);</span>
<a name="l00261"></a>00261 <span class="comment"> m_ep.m_exponentBase.BERDecode(seq);</span>
<a name="l00262"></a>00262 <span class="comment"> m_ep.m_windowSize = m_ep.m_exponentBase.BitCount() - 1;</span>
<a name="l00263"></a>00263 <span class="comment"> m_ep.m_bases.clear();</span>
<a name="l00264"></a>00264 <span class="comment"> while (!seq.EndReached())</span>
<a name="l00265"></a>00265 <span class="comment"> m_ep.m_bases.push_back(m_ec->BERDecodePoint(seq));</span>
<a name="l00266"></a>00266 <span class="comment"> seq.MessageEnd();</span>
<a name="l00267"></a>00267 <span class="comment">}</span>
<a name="l00268"></a>00268 <span class="comment"></span>
<a name="l00269"></a>00269 <span class="comment">void EcPrecomputation<EC2N>::Save(BufferedTransformation &bt) const</span>
<a name="l00270"></a>00270 <span class="comment">{</span>
<a name="l00271"></a>00271 <span class="comment"> DERSequenceEncoder seq(bt);</span>
<a name="l00272"></a>00272 <span class="comment"> DEREncodeUnsigned<word32>(seq, 1); // version</span>
<a name="l00273"></a>00273 <span class="comment"> m_ep.m_exponentBase.DEREncode(seq);</span>
<a name="l00274"></a>00274 <span class="comment"> for (unsigned i=0; i<m_ep.m_bases.size(); i++)</span>
<a name="l00275"></a>00275 <span class="comment"> m_ec->DEREncodePoint(seq, m_ep.m_bases[i]);</span>
<a name="l00276"></a>00276 <span class="comment"> seq.MessageEnd();</span>
<a name="l00277"></a>00277 <span class="comment">}</span>
<a name="l00278"></a>00278 <span class="comment"></span>
<a name="l00279"></a>00279 <span class="comment">EC2N::Point EcPrecomputation<EC2N>::Exponentiate(const Integer &exponent) const</span>
<a name="l00280"></a>00280 <span class="comment">{</span>
<a name="l00281"></a>00281 <span class="comment"> return m_ep.Exponentiate(exponent);</span>
<a name="l00282"></a>00282 <span class="comment">}</span>
<a name="l00283"></a>00283 <span class="comment"></span>
<a name="l00284"></a>00284 <span class="comment">EC2N::Point EcPrecomputation<EC2N>::CascadeExponentiate(const Integer &exponent, const DL_FixedBasePrecomputation<Element> &pc2, const Integer &exponent2) const</span>
<a name="l00285"></a>00285 <span class="comment">{</span>
<a name="l00286"></a>00286 <span class="comment"> return m_ep.CascadeExponentiate(exponent, static_cast<const EcPrecomputation<EC2N> &>(pc2).m_ep, exponent2);</span>
<a name="l00287"></a>00287 <span class="comment">}</span>
<a name="l00288"></a>00288 <span class="comment">*/</span>
<a name="l00289"></a>00289
<a name="l00290"></a>00290 NAMESPACE_END
<a name="l00291"></a>00291
<a name="l00292"></a>00292 <span class="preprocessor">#endif</span>
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