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<a name="l00105"></a>00105 <span class="keywordflow">if</span> (encodedPointLen != <a class="code" href="class_e_c_p.html#4273ed51110725435ddeefcac166c29d">EncodedPointSize</a>(<span class="keyword">false</span>))<a name="l00106"></a>00106 <span class="keywordflow">return</span> <span class="keyword">false</span>;<a name="l00107"></a>00107 <a name="l00108"></a>00108 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> len = <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_modular_arithmetic.html#5897aea2ee78595979f8f261130c93ee">MaxElementByteLength</a>();<a name="l00109"></a>00109 P.<a class="code" href="struct_e_c_p_point.html#806dedcf077e22de7904ccfd7987bcf9">identity</a> = <span class="keyword">false</span>;<a name="l00110"></a>00110 P.<a class="code" href="struct_e_c_p_point.html#24bbcc7eb375ebe2b46d2ac9ee6bb0a8">x</a>.<a class="code" href="class_integer.html#e91fee9e9873f3412f47e6d647545099">Decode</a>(bt, len);<a name="l00111"></a>00111 P.<a class="code" href="struct_e_c_p_point.html#b47b82046f543e809bd90d78bf2c85bf">y</a>.<a class="code" href="class_integer.html#e91fee9e9873f3412f47e6d647545099">Decode</a>(bt, len);<a name="l00112"></a>00112 <span class="keywordflow">return</span> <span class="keyword">true</span>;<a name="l00113"></a>00113 }<a name="l00114"></a>00114 <span class="keywordflow">default</span>:<a name="l00115"></a>00115 <span class="keywordflow">return</span> <span class="keyword">false</span>;<a name="l00116"></a>00116 }<a name="l00117"></a>00117 }<a name="l00118"></a>00118 <a name="l00119"></a>00119 <span class="keywordtype">void</span> ECP::EncodePoint(<a class="code" href="class_buffered_transformation.html" title="interface for buffered transformations">BufferedTransformation</a> &bt, <span class="keyword">const</span> <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> &P, <span class="keywordtype">bool</span> compressed)<span class="keyword"> const</span><a name="l00120"></a>00120 <span class="keyword"></span>{<a name="l00121"></a>00121 <span class="keywordflow">if</span> (P.identity)<a name="l00122"></a>00122 <a class="code" href="class_null_store.html" title="empty store">NullStore</a>().TransferTo(bt, <a class="code" href="class_e_c_p.html#4273ed51110725435ddeefcac166c29d">EncodedPointSize</a>(compressed));<a name="l00123"></a>00123 <span class="keywordflow">else</span> <span class="keywordflow">if</span> (compressed)<a name="l00124"></a>00124 {<a name="l00125"></a>00125 bt.<a class="code" href="class_buffered_transformation.html#e70658b0d271f8e114ac6c3cc9774ede" title="input a byte for processing">Put</a>(2 + P.y.GetBit(0));<a name="l00126"></a>00126 P.x.Encode(bt, <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().MaxElementByteLength());<a name="l00127"></a>00127 }<a name="l00128"></a>00128 <span class="keywordflow">else</span><a name="l00129"></a>00129 {<a name="l00130"></a>00130 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> len = <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_modular_arithmetic.html#5897aea2ee78595979f8f261130c93ee">MaxElementByteLength</a>();<a name="l00131"></a>00131 bt.<a class="code" href="class_buffered_transformation.html#e70658b0d271f8e114ac6c3cc9774ede" title="input a byte for processing">Put</a>(4); <span class="comment">// uncompressed</span><a name="l00132"></a>00132 P.x.Encode(bt, len);<a name="l00133"></a>00133 P.y.Encode(bt, len);<a name="l00134"></a>00134 }<a name="l00135"></a>00135 }<a name="l00136"></a>00136 <a name="l00137"></a>00137 <span class="keywordtype">void</span> ECP::EncodePoint(byte *encodedPoint, <span class="keyword">const</span> <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> &P, <span class="keywordtype">bool</span> compressed)<span class="keyword"> const</span><a name="l00138"></a>00138 <span class="keyword"></span>{<a name="l00139"></a>00139 <a class="code" href="class_array_sink.html" title="Copy input to a memory buffer.">ArraySink</a> sink(encodedPoint, <a class="code" href="class_e_c_p.html#4273ed51110725435ddeefcac166c29d">EncodedPointSize</a>(compressed));<a name="l00140"></a>00140 EncodePoint(sink, P, compressed);<a name="l00141"></a>00141 assert(sink.TotalPutLength() == <a class="code" href="class_e_c_p.html#4273ed51110725435ddeefcac166c29d">EncodedPointSize</a>(compressed));<a name="l00142"></a>00142 }<a name="l00143"></a>00143 <a name="l00144"></a>00144 <a class="code" href="struct_e_c_p_point.html" title="Elliptical Curve Point.">ECP::Point</a> ECP::BERDecodePoint(<a class="code" href="class_buffered_transformation.html" title="interface for buffered transformations">BufferedTransformation</a> &bt)<span class="keyword"> const</span><a name="l00145"></a>00145 <span class="keyword"></span>{<a name="l00146"></a>00146 <a class="code" href="class_sec_block.html" title="a block of memory allocated using A">SecByteBlock</a> str;<a name="l00147"></a>00147 BERDecodeOctetString(bt, str);<a name="l00148"></a>00148 <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> P;<a name="l00149"></a>00149 <span class="keywordflow">if</span> (!DecodePoint(P, str, str.<a class="code" href="class_sec_block.html#f5999bffe3193e62719cc0792b0282a7">size</a>()))<a name="l00150"></a>00150 BERDecodeError();<a name="l00151"></a>00151 <span class="keywordflow">return</span> P;<a name="l00152"></a>00152 }<a name="l00153"></a>00153 <a name="l00154"></a>00154 <span class="keywordtype">void</span> ECP::DEREncodePoint(<a class="code" href="class_buffered_transformation.html" title="interface for buffered transformations">BufferedTransformation</a> &bt, <span class="keyword">const</span> <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> &P, <span class="keywordtype">bool</span> compressed)<span class="keyword"> const</span><a name="l00155"></a>00155 <span class="keyword"></span>{<a name="l00156"></a>00156 <a class="code" href="class_sec_block.html" title="a block of memory allocated using A">SecByteBlock</a> str(<a class="code" href="class_e_c_p.html#4273ed51110725435ddeefcac166c29d">EncodedPointSize</a>(compressed));<a name="l00157"></a>00157 EncodePoint(str, P, compressed);<a name="l00158"></a>00158 DEREncodeOctetString(bt, str);<a name="l00159"></a>00159 }<a name="l00160"></a>00160 <a name="l00161"></a>00161 <span class="keywordtype">bool</span> ECP::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="l00162"></a>00162 <span class="keyword"></span>{<a name="l00163"></a>00163 <a class="code" href="class_integer.html" title="multiple precision integer and basic arithmetics">Integer</a> p = <a class="code" href="class_e_c_p.html#b0c01cf1ebf788ba647fb8a076c6dcee">FieldSize</a>();<a name="l00164"></a>00164 <a name="l00165"></a>00165 <span class="keywordtype">bool</span> pass = p.<a class="code" href="class_integer.html#ed4bb7208a18b986ef3e1a7d92e06d1d">IsOdd</a>();<a name="l00166"></a>00166 pass = pass && !m_a.<a class="code" href="class_integer.html#d767ae81c89be3804da8785e132d2d1f">IsNegative</a>() && m_a<p && !m_b.<a class="code" href="class_integer.html#d767ae81c89be3804da8785e132d2d1f">IsNegative</a>() && m_b<p;<a name="l00167"></a>00167 <a name="l00168"></a>00168 <span class="keywordflow">if</span> (level >= 1)<a name="l00169"></a>00169 pass = pass && ((4*m_a*m_a*m_a+27*m_b*m_b)%p).<a class="code" href="class_integer.html#13ddbfd8e9729932c2a99b0dff530978">IsPositive</a>();<a name="l00170"></a>00170 <a name="l00171"></a>00171 <span class="keywordflow">if</span> (level >= 2)<a name="l00172"></a>00172 pass = pass && VerifyPrime(rng, p);<a name="l00173"></a>00173 <a name="l00174"></a>00174 <span class="keywordflow">return</span> pass;<a name="l00175"></a>00175 }<a name="l00176"></a>00176 <a name="l00177"></a>00177 <span class="keywordtype">bool</span> ECP::VerifyPoint(<span class="keyword">const</span> <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> &P)<span class="keyword"> const</span><a name="l00178"></a>00178 <span class="keyword"></span>{<a name="l00179"></a>00179 <span class="keyword">const</span> <a class="code" href="class_e_c_p.html#337e68ddf10edab098c55474d52c4d04">FieldElement</a> &x = P.x, &y = P.y;<a name="l00180"></a>00180 <a class="code" href="class_integer.html" title="multiple precision integer and basic arithmetics">Integer</a> p = <a class="code" href="class_e_c_p.html#b0c01cf1ebf788ba647fb8a076c6dcee">FieldSize</a>();<a name="l00181"></a>00181 <span class="keywordflow">return</span> P.identity ||<a name="l00182"></a>00182 (!x.IsNegative() && x<p && !y.<a class="code" href="class_integer.html#d767ae81c89be3804da8785e132d2d1f">IsNegative</a>() && y<p<a name="l00183"></a>00183 && !(((x*x+m_a)*x+m_b-y*y)%p));<a name="l00184"></a>00184 }<a name="l00185"></a>00185 <a name="l00186"></a>00186 <span class="keywordtype">bool</span> ECP::Equal(<span class="keyword">const</span> <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> &P, <span class="keyword">const</span> <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> &Q)<span class="keyword"> const</span><a name="l00187"></a>00187 <span class="keyword"></span>{<a name="l00188"></a>00188 <span class="keywordflow">if</span> (P.identity && Q.identity)<a name="l00189"></a>00189 <span class="keywordflow">return</span> <span class="keyword">true</span>;<a name="l00190"></a>00190 <a name="l00191"></a>00191 <span class="keywordflow">if</span> (P.identity && !Q.identity)<a name="l00192"></a>00192 <span class="keywordflow">return</span> <span class="keyword">false</span>;<a name="l00193"></a>00193 <a name="l00194"></a>00194 <span class="keywordflow">if</span> (!P.identity && Q.identity)<a name="l00195"></a>00195 <span class="keywordflow">return</span> <span class="keyword">false</span>;<a name="l00196"></a>00196 <a name="l00197"></a>00197 <span class="keywordflow">return</span> (<a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().Equal(P.x,Q.x) && <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().Equal(P.y,Q.y));<a name="l00198"></a>00198 }<a name="l00199"></a>00199 <a name="l00200"></a>00200 <span class="keyword">const</span> <a class="code" href="struct_e_c_p_point.html" title="Elliptical Curve Point.">ECP::Point</a>& ECP::Identity()<span class="keyword"> const</span><a name="l00201"></a>00201 <span class="keyword"></span>{<a name="l00202"></a>00202 <span class="keywordflow">return</span> <a class="code" href="class_singleton.html">Singleton<Point></a>().Ref();<a name="l00203"></a>00203 }<a name="l00204"></a>00204 <a name="l00205"></a>00205 <span class="keyword">const</span> <a class="code" href="struct_e_c_p_point.html" title="Elliptical Curve Point.">ECP::Point</a>& ECP::Inverse(<span class="keyword">const</span> <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> &P)<span class="keyword"> const</span><a name="l00206"></a>00206 <span class="keyword"></span>{<a name="l00207"></a>00207 <span class="keywordflow">if</span> (P.identity)<a name="l00208"></a>00208 <span class="keywordflow">return</span> P;<a name="l00209"></a>00209 <span class="keywordflow">else</span><a name="l00210"></a>00210 {<a name="l00211"></a>00211 m_R.<a class="code" href="struct_e_c_p_point.html#806dedcf077e22de7904ccfd7987bcf9">identity</a> = <span class="keyword">false</span>;<a name="l00212"></a>00212 m_R.<a class="code" href="struct_e_c_p_point.html#24bbcc7eb375ebe2b46d2ac9ee6bb0a8">x</a> = P.x;<a name="l00213"></a>00213 m_R.<a class="code" href="struct_e_c_p_point.html#b47b82046f543e809bd90d78bf2c85bf">y</a> = <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_modular_arithmetic.html#7e3a9d9ae5e151fdd75f00f7c22bdda3">Inverse</a>(P.y);<a name="l00214"></a>00214 <span class="keywordflow">return</span> m_R;<a name="l00215"></a>00215 }<a name="l00216"></a>00216 }<a name="l00217"></a>00217 <a name="l00218"></a>00218 <span class="keyword">const</span> <a class="code" href="struct_e_c_p_point.html" title="Elliptical Curve Point.">ECP::Point</a>& ECP::Add(<span class="keyword">const</span> <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> &P, <span class="keyword">const</span> <a class="code" href="class_e_c_p.html#99c34a437007f32af4e6c4ae275358ea">Point</a> &Q)<span class="keyword"> const</span><a name="l00219"></a>00219 <span class="keyword"></span>{<a name="l00220"></a>00220 <span class="keywordflow">if</span> (P.identity) <span class="keywordflow">return</span> Q;<a name="l00221"></a>00221 <span class="keywordflow">if</span> (Q.identity) <span class="keywordflow">return</span> P;<a name="l00222"></a>00222 <span class="keywordflow">if</span> (<a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().Equal(P.x, Q.x))<a name="l00223"></a>00223 <span class="keywordflow">return</span> <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_modular_arithmetic.html#89c5edea6e87341761c35ab03a46bcc0">Equal</a>(P.y, Q.y) ? Double(P) : Identity();<a name="l00224"></a>00224 <a name="l00225"></a>00225 <a class="code" href="class_e_c_p.html#337e68ddf10edab098c55474d52c4d04">FieldElement</a> t = <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_modular_arithmetic.html#e4705633e8ca4308894f9a26c6f2881c">Subtract</a>(Q.y, P.y);<a name="l00226"></a>00226 t = <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_modular_arithmetic.html#584d214676856d1463e14c6407d1cd31">Divide</a>(t, <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_abstract_group.html#a19e1bef00198fb30eb01df3f7076717">Subtract</a>(Q.x, P.x));<a name="l00227"></a>00227 <a class="code" href="class_e_c_p.html#337e68ddf10edab098c55474d52c4d04">FieldElement</a> x = <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_modular_arithmetic.html#e4705633e8ca4308894f9a26c6f2881c">Subtract</a>(<a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_abstract_group.html#a19e1bef00198fb30eb01df3f7076717">Subtract</a>(<a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_square.html" title="Square">Square</a>(t), P.x), Q.<a class="code" href="struct_e_c_p_point.html#24bbcc7eb375ebe2b46d2ac9ee6bb0a8">x</a>);<a name="l00228"></a>00228 m_R.<a class="code" href="struct_e_c_p_point.html#b47b82046f543e809bd90d78bf2c85bf">y</a> = <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_modular_arithmetic.html#e4705633e8ca4308894f9a26c6f2881c">Subtract</a>(<a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_e_c_p.html#81862b8619979835884f0239012e2ce9">Multiply</a>(t, <a class="code" href="class_e_c_p.html#e996fce212244df79b83a587317f7423">GetField</a>().<a class="code" href="class_abstract_group.html#a19e1bef00198fb30eb01df3f7076717">Subtract</a>(P.x, x)), P.<a class="code" href="struct_e_c_p_point.html#b47b82046f543e809bd90d78bf2c85bf">y</a>);<a name="l00229"></a>00229 ⌨️ 快捷键说明
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