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00221                 5, 18, 31, 10,
00222                 2,  8, 24, 14,
00223            32, 27,  3,  9,
00224            19, 13, 30,  6,
00225            22, 11,  4, 25
00226 };
00227 <span class="preprocessor">#endif</span>
00228 <span class="preprocessor"></span>
00229 <span class="comment">/* permuted choice table (key) */</span>
00230 <span class="keyword">static</span> <span class="keyword">const</span> byte pc1[] = {
00231            57, 49, 41, 33, 25, 17,  9,
00232                 1, 58, 50, 42, 34, 26, 18,
00233            10,  2, 59, 51, 43, 35, 27,
00234            19, 11,  3, 60, 52, 44, 36,
00235 
00236            63, 55, 47, 39, 31, 23, 15,
00237                 7, 62, 54, 46, 38, 30, 22,
00238            14,  6, 61, 53, 45, 37, 29,
00239            21, 13,  5, 28, 20, 12,  4
00240 };
00241 
00242 <span class="comment">/* number left rotations of pc1 */</span>
00243 <span class="keyword">static</span> <span class="keyword">const</span> byte totrot[] = {
00244            1,2,4,6,8,10,12,14,15,17,19,21,23,25,27,28
00245 };
00246 
00247 <span class="comment">/* permuted choice key (table) */</span>
00248 <span class="keyword">static</span> <span class="keyword">const</span> byte pc2[] = {
00249            14, 17, 11, 24,  1,  5,
00250                 3, 28, 15,  6, 21, 10,
00251            23, 19, 12,  4, 26,  8,
00252            16,  7, 27, 20, 13,  2,
00253            41, 52, 31, 37, 47, 55,
00254            30, 40, 51, 45, 33, 48,
00255            44, 49, 39, 56, 34, 53,
00256            46, 42, 50, 36, 29, 32
00257 };
00258 
00259 <span class="comment">/* End of DES-defined tables */</span>
00260 
00261 <span class="comment">/* bit 0 is left-most in byte */</span>
00262 <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">int</span> bytebit[] = {
00263            0200,0100,040,020,010,04,02,01
00264 };
00265 
00266 <span class="comment">/* Set key (initialize key schedule array) */</span>
00267 <span class="keywordtype">void</span> RawDES::UncheckedSetKey(CipherDir dir, <span class="keyword">const</span> byte *key, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> length)
00268 {
00269         <a class="code" href="class_sec_block.html">SecByteBlock</a> buffer(56+56+8);
00270         byte *<span class="keyword">const</span> pc1m=buffer;                 <span class="comment">/* place to modify pc1 into */</span>
00271         byte *<span class="keyword">const</span> pcr=pc1m+56;                 <span class="comment">/* place to rotate pc1 into */</span>
00272         byte *<span class="keyword">const</span> ks=pcr+56;
00273         <span class="keyword">register</span> <span class="keywordtype">int</span> i,j,l;
00274         <span class="keywordtype">int</span> m;
00275         
00276         <span class="keywordflow">for</span> (j=0; j&lt;56; j++) {          <span class="comment">/* convert pc1 to bits of key */</span>
00277                 l=pc1[j]-1;             <span class="comment">/* integer bit location  */</span>
00278                 m = l &amp; 07;             <span class="comment">/* find bit              */</span>
00279                 pc1m[j]=(key[l&gt;&gt;3] &amp;    <span class="comment">/* find which key byte l is in */</span>
00280                         bytebit[m])     <span class="comment">/* and which bit of that byte */</span>
00281                         ? 1 : 0;        <span class="comment">/* and store 1-bit result */</span>
00282         }
00283         <span class="keywordflow">for</span> (i=0; i&lt;16; i++) {          <span class="comment">/* key chunk for each iteration */</span>
00284                 memset(ks,0,8);         <span class="comment">/* Clear key schedule */</span>
00285                 <span class="keywordflow">for</span> (j=0; j&lt;56; j++)    <span class="comment">/* rotate pc1 the right amount */</span>
00286                         pcr[j] = pc1m[(l=j+totrot[i])&lt;(j&lt;28? 28 : 56) ? l: l-28];
00287                 <span class="comment">/* rotate left and right halves independently */</span>
00288                 <span class="keywordflow">for</span> (j=0; j&lt;48; j++){   <span class="comment">/* select bits individually */</span>
00289                         <span class="comment">/* check bit that goes to ks[j] */</span>
00290                         <span class="keywordflow">if</span> (pcr[pc2[j]-1]){
00291                                 <span class="comment">/* mask it in if it's there */</span>
00292                                 l= j % 6;
00293                                 ks[j/6] |= bytebit[l] &gt;&gt; 2;
00294                         }
00295                 }
00296                 <span class="comment">/* Now convert to odd/even interleaved form for use in F */</span>
00297                 k[2*i] = ((word32)ks[0] &lt;&lt; 24)
00298                         | ((word32)ks[2] &lt;&lt; 16)
00299                         | ((word32)ks[4] &lt;&lt; 8)
00300                         | ((word32)ks[6]);
00301                 k[2*i+1] = ((word32)ks[1] &lt;&lt; 24)
00302                         | ((word32)ks[3] &lt;&lt; 16)
00303                         | ((word32)ks[5] &lt;&lt; 8)
00304                         | ((word32)ks[7]);
00305         }
00306         
00307         <span class="keywordflow">if</span> (dir==DECRYPTION)     <span class="comment">// reverse key schedule order</span>
00308                 <span class="keywordflow">for</span> (i=0; i&lt;16; i+=2)
00309                 {
00310                         std::swap(k[i], k[32-2-i]);
00311                         std::swap(k[i+1], k[32-1-i]);
00312                 }
00313 }
00314 
00315 <span class="keywordtype">void</span> RawDES::RawProcessBlock(word32 &amp;l_, word32 &amp;r_)<span class="keyword"> const</span>
00316 <span class="keyword"></span>{
00317         word32 l = l_, r = r_;
00318         <span class="keyword">const</span> word32 *kptr=k;
00319 
00320         <span class="keywordflow">for</span> (<span class="keywordtype">unsigned</span> i=0; i&lt;8; i++)
00321         {
00322                 word32 work = rotrFixed(r, 4U) ^ kptr[4*i+0];
00323                 l ^= Spbox[6][(work) &amp; 0x3f]
00324                   ^  Spbox[4][(work &gt;&gt; 8) &amp; 0x3f]
00325                   ^  Spbox[2][(work &gt;&gt; 16) &amp; 0x3f]
00326                   ^  Spbox[0][(work &gt;&gt; 24) &amp; 0x3f];
00327                 work = r ^ kptr[4*i+1];
00328                 l ^= Spbox[7][(work) &amp; 0x3f]
00329                   ^  Spbox[5][(work &gt;&gt; 8) &amp; 0x3f]
00330                   ^  Spbox[3][(work &gt;&gt; 16) &amp; 0x3f]
00331                   ^  Spbox[1][(work &gt;&gt; 24) &amp; 0x3f];
00332 
00333                 work = rotrFixed(l, 4U) ^ kptr[4*i+2];
00334                 r ^= Spbox[6][(work) &amp; 0x3f]
00335                   ^  Spbox[4][(work &gt;&gt; 8) &amp; 0x3f]
00336                   ^  Spbox[2][(work &gt;&gt; 16) &amp; 0x3f]
00337                   ^  Spbox[0][(work &gt;&gt; 24) &amp; 0x3f];
00338                 work = l ^ kptr[4*i+3];
00339                 r ^= Spbox[7][(work) &amp; 0x3f]
00340                   ^  Spbox[5][(work &gt;&gt; 8) &amp; 0x3f]
00341                   ^  Spbox[3][(work &gt;&gt; 16) &amp; 0x3f]
00342                   ^  Spbox[1][(work &gt;&gt; 24) &amp; 0x3f];
00343         }
00344 
00345         l_ = l; r_ = r;
00346 }
00347 
00348 <span class="keywordtype">void</span> DES_EDE2::Base::UncheckedSetKey(CipherDir dir, <span class="keyword">const</span> byte *key, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> length)
00349 {
00350         AssertValidKeyLength(length);
00351 
00352         m_des1.UncheckedSetKey(dir, key);
00353         m_des2.UncheckedSetKey(ReverseCipherDir(dir), key+8);
00354 }
00355 
00356 <span class="keywordtype">void</span> DES_EDE2::Base::ProcessAndXorBlock(<span class="keyword">const</span> byte *inBlock, <span class="keyword">const</span> byte *xorBlock, byte *outBlock)<span class="keyword"> const</span>
00357 <span class="keyword"></span>{
00358         word32 l,r;
00359         Block::Get(inBlock)(l)(r);
00360         IPERM(l,r);
00361         m_des1.RawProcessBlock(l, r);
00362         m_des2.RawProcessBlock(r, l);
00363         m_des1.RawProcessBlock(l, r);
00364         FPERM(l,r);
00365         Block::Put(xorBlock, outBlock)(r)(l);
00366 }
00367 
00368 <span class="keywordtype">void</span> DES_EDE3::Base::UncheckedSetKey(CipherDir dir, <span class="keyword">const</span> byte *key, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> length)
00369 {
00370         AssertValidKeyLength(length);
00371 
00372         m_des1.UncheckedSetKey(dir, key+(dir==ENCRYPTION?0:2*8));
00373         m_des2.UncheckedSetKey(ReverseCipherDir(dir), key+8);
00374         m_des3.UncheckedSetKey(dir, key+(dir==DECRYPTION?0:2*8));
00375 }
00376 
00377 <span class="keywordtype">void</span> DES_EDE3::Base::ProcessAndXorBlock(<span class="keyword">const</span> byte *inBlock, <span class="keyword">const</span> byte *xorBlock, byte *outBlock)<span class="keyword"> const</span>
00378 <span class="keyword"></span>{
00379         word32 l,r;
00380         Block::Get(inBlock)(l)(r);
00381         IPERM(l,r);
00382         m_des1.RawProcessBlock(l, r);
00383         m_des2.RawProcessBlock(r, l);
00384         m_des3.RawProcessBlock(l, r);
00385         FPERM(l,r);
00386         Block::Put(xorBlock, outBlock)(r)(l);
00387 }
00388 
00389 <span class="preprocessor">#endif  // #ifndef CRYPTOPP_IMPORTS</span>
00390 <span class="preprocessor"></span>
00391 <span class="keyword">static</span> <span class="keyword">inline</span> <span class="keywordtype">bool</span> CheckParity(byte b)
00392 {
00393         <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> a = b ^ (b &gt;&gt; 4);
00394         <span class="keywordflow">return</span> ((a ^ (a&gt;&gt;1) ^ (a&gt;&gt;2) ^ (a&gt;&gt;3)) &amp; 1) == 1;
00395 }
00396 
<a name="l00397"></a><a class="code" href="class_d_e_s.html#_d_e_se0">00397</a> <span class="keywordtype">bool</span> <a class="code" href="class_d_e_s.html#_d_e_se0">DES::CheckKeyParityBits</a>(<span class="keyword">const</span> byte *key)
00398 {
00399         <span class="keywordflow">for</span> (<span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i=0; i&lt;8; i++)
00400                 <span class="keywordflow">if</span> (!CheckParity(key[i]))
00401                         <span class="keywordflow">return</span> <span class="keyword">false</span>;
00402         <span class="keywordflow">return</span> <span class="keyword">true</span>;
00403 }
00404 
<a name="l00405"></a><a class="code" href="class_d_e_s.html#_d_e_se1">00405</a> <span class="keywordtype">void</span> <a class="code" href="class_d_e_s.html#_d_e_se1">DES::CorrectKeyParityBits</a>(byte *key)
00406 {
00407         <span class="keywordflow">for</span> (<span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i=0; i&lt;8; i++)
00408                 <span class="keywordflow">if</span> (!CheckParity(key[i]))
00409                         key[i] ^= 1;
00410 }
00411 
00412 <span class="comment">// Encrypt or decrypt a block of data in ECB mode</span>
00413 <span class="keywordtype">void</span> DES::Base::ProcessAndXorBlock(<span class="keyword">const</span> byte *inBlock, <span class="keyword">const</span> byte *xorBlock, byte *outBlock)<span class="keyword"> const</span>
00414 <span class="keyword"></span>{
00415         word32 l,r;
00416         Block::Get(inBlock)(l)(r);
00417         IPERM(l,r);
00418         RawProcessBlock(l, r);
00419         FPERM(l,r);
00420         Block::Put(xorBlock, outBlock)(r)(l);
00421 }
00422 
00423 <span class="keywordtype">void</span> DES_XEX3::Base::UncheckedSetKey(CipherDir dir, <span class="keyword">const</span> byte *key, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> length)
00424 {
00425         AssertValidKeyLength(length);
00426 
00427         memcpy(m_x1, key+(dir==ENCRYPTION?0:2*8), BLOCKSIZE);
00428         m_des.UncheckedSetKey(dir, key+8);
00429         memcpy(m_x3, key+(dir==DECRYPTION?0:2*8), BLOCKSIZE);
00430 }
00431 
00432 <span class="keywordtype">void</span> DES_XEX3::Base::ProcessAndXorBlock(<span class="keyword">const</span> byte *inBlock, <span class="keyword">const</span> byte *xorBlock, byte *outBlock)<span class="keyword"> const</span>
00433 <span class="keyword"></span>{
00434         xorbuf(outBlock, inBlock, m_x1, BLOCKSIZE);
00435         m_des.ProcessAndXorBlock(outBlock, xorBlock, outBlock);
00436         xorbuf(outBlock, m_x3, BLOCKSIZE);
00437 }
00438 
00439 NAMESPACE_END
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