Crypto++
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00001 // cast.cpp - written and placed in the public domain by Wei Dai and Leonard Janke 00002 // based on Steve Reid's public domain cast.c 00003 00004 #include "pch.h" 00005 #include "cast.h" 00006 #include "misc.h" 00007 00008 NAMESPACE_BEGIN(CryptoPP) 00009 00010 /* Macros to access 8-bit bytes out of a 32-bit word */ 00011 #define U8a(x) GETBYTE(x,3) 00012 #define U8b(x) GETBYTE(x,2) 00013 #define U8c(x) GETBYTE(x,1) 00014 #define U8d(x) GETBYTE(x,0) 00015 00016 /* CAST uses three different round functions */ 00017 #define f1(l, r, km, kr) \ 00018 t = rotlVariable(km + r, kr); \ 00019 l ^= ((S[0][U8a(t)] ^ S[1][U8b(t)]) - \ 00020 S[2][U8c(t)]) + S[3][U8d(t)]; 00021 #define f2(l, r, km, kr) \ 00022 t = rotlVariable(km ^ r, kr); \ 00023 l ^= ((S[0][U8a(t)] - S[1][U8b(t)]) + \ 00024 S[2][U8c(t)]) ^ S[3][U8d(t)]; 00025 #define f3(l, r, km, kr) \ 00026 t = rotlVariable(km - r, kr); \ 00027 l ^= ((S[0][U8a(t)] + S[1][U8b(t)]) ^ \ 00028 S[2][U8c(t)]) - S[3][U8d(t)]; 00029 00030 #define F1(l, r, i, j) f1(l, r, K[i], K[i+j]) 00031 #define F2(l, r, i, j) f2(l, r, K[i], K[i+j]) 00032 #define F3(l, r, i, j) f3(l, r, K[i], K[i+j]) 00033 00034 typedef BlockGetAndPut<word32, BigEndian> Block; 00035 00036 void CAST128::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const 00037 { 00038 word32 t, l, r; 00039 00040 /* Get inblock into l,r */ 00041 Block::Get(inBlock)(l)(r); 00042 /* Do the work */ 00043 F1(l, r, 0, 16); 00044 F2(r, l, 1, 16); 00045 F3(l, r, 2, 16); 00046 F1(r, l, 3, 16); 00047 F2(l, r, 4, 16); 00048 F3(r, l, 5, 16); 00049 F1(l, r, 6, 16); 00050 F2(r, l, 7, 16); 00051 F3(l, r, 8, 16); 00052 F1(r, l, 9, 16); 00053 F2(l, r, 10, 16); 00054 F3(r, l, 11, 16); 00055 /* Only do full 16 rounds if key length > 80 bits */ 00056 if (!reduced) { 00057 F1(l, r, 12, 16); 00058 F2(r, l, 13, 16); 00059 F3(l, r, 14, 16); 00060 F1(r, l, 15, 16); 00061 } 00062 /* Put l,r into outblock */ 00063 Block::Put(xorBlock, outBlock)(r)(l); 00064 } 00065 00066 void CAST128::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const 00067 { 00068 word32 t, l, r; 00069 00070 /* Get inblock into l,r */ 00071 Block::Get(inBlock)(r)(l); 00072 /* Only do full 16 rounds if key length > 80 bits */ 00073 if (!reduced) { 00074 F1(r, l, 15, 16); 00075 F3(l, r, 14, 16); 00076 F2(r, l, 13, 16); 00077 F1(l, r, 12, 16); 00078 } 00079 F3(r, l, 11, 16); 00080 F2(l, r, 10, 16); 00081 F1(r, l, 9, 16); 00082 F3(l, r, 8, 16); 00083 F2(r, l, 7, 16); 00084 F1(l, r, 6, 16); 00085 F3(r, l, 5, 16); 00086 F2(l, r, 4, 16); 00087 F1(r, l, 3, 16); 00088 F3(l, r, 2, 16); 00089 F2(r, l, 1, 16); 00090 F1(l, r, 0, 16); 00091 /* Put l,r into outblock */ 00092 Block::Put(xorBlock, outBlock)(l)(r); 00093 /* Wipe clean */ 00094 t = l = r = 0; 00095 } 00096 00097 void CAST128::Base::UncheckedSetKey(const byte *userKey, unsigned int keylength, const NameValuePairs &) 00098 { 00099 AssertValidKeyLength(keylength); 00100 00101 reduced = (keylength <= 10); 00102 00103 word32 X[4], Z[4]; 00104 GetUserKey(BIG_ENDIAN_ORDER, X, 4, userKey, keylength); 00105 00106 #define x(i) GETBYTE(X[i/4], 3-i%4) 00107 #define z(i) GETBYTE(Z[i/4], 3-i%4) 00108 00109 unsigned int i; 00110 for (i=0; i<=16; i+=16) 00111 { 00112 // this part is copied directly from RFC 2144 (with some search and replace) by Wei Dai 00113 Z[0] = X[0] ^ S[4][x(0xD)] ^ S[5][x(0xF)] ^ S[6][x(0xC)] ^ S[7][x(0xE)] ^ S[6][x(0x8)]; 00114 Z[1] = X[2] ^ S[4][z(0x0)] ^ S[5][z(0x2)] ^ S[6][z(0x1)] ^ S[7][z(0x3)] ^ S[7][x(0xA)]; 00115 Z[2] = X[3] ^ S[4][z(0x7)] ^ S[5][z(0x6)] ^ S[6][z(0x5)] ^ S[7][z(0x4)] ^ S[4][x(0x9)]; 00116 Z[3] = X[1] ^ S[4][z(0xA)] ^ S[5][z(0x9)] ^ S[6][z(0xB)] ^ S[7][z(0x8)] ^ S[5][x(0xB)]; 00117 K[i+0] = S[4][z(0x8)] ^ S[5][z(0x9)] ^ S[6][z(0x7)] ^ S[7][z(0x6)] ^ S[4][z(0x2)]; 00118 K[i+1] = S[4][z(0xA)] ^ S[5][z(0xB)] ^ S[6][z(0x5)] ^ S[7][z(0x4)] ^ S[5][z(0x6)]; 00119 K[i+2] = S[4][z(0xC)] ^ S[5][z(0xD)] ^ S[6][z(0x3)] ^ S[7][z(0x2)] ^ S[6][z(0x9)]; 00120 K[i+3] = S[4][z(0xE)] ^ S[5][z(0xF)] ^ S[6][z(0x1)] ^ S[7][z(0x0)] ^ S[7][z(0xC)]; 00121 X[0] = Z[2] ^ S[4][z(0x5)] ^ S[5][z(0x7)] ^ S[6][z(0x4)] ^ S[7][z(0x6)] ^ S[6][z(0x0)]; 00122 X[1] = Z[0] ^ S[4][x(0x0)] ^ S[5][x(0x2)] ^ S[6][x(0x1)] ^ S[7][x(0x3)] ^ S[7][z(0x2)]; 00123 X[2] = Z[1] ^ S[4][x(0x7)] ^ S[5][x(0x6)] ^ S[6][x(0x5)] ^ S[7][x(0x4)] ^ S[4][z(0x1)]; 00124 X[3] = Z[3] ^ S[4][x(0xA)] ^ S[5][x(0x9)] ^ S[6][x(0xB)] ^ S[7][x(0x8)] ^ S[5][z(0x3)]; 00125 K[i+4] = S[4][x(0x3)] ^ S[5][x(0x2)] ^ S[6][x(0xC)] ^ S[7][x(0xD)] ^ S[4][x(0x8)]; 00126 K[i+5] = S[4][x(0x1)] ^ S[5][x(0x0)] ^ S[6][x(0xE)] ^ S[7][x(0xF)] ^ S[5][x(0xD)]; 00127 K[i+6] = S[4][x(0x7)] ^ S[5][x(0x6)] ^ S[6][x(0x8)] ^ S[7][x(0x9)] ^ S[6][x(0x3)]; 00128 K[i+7] = S[4][x(0x5)] ^ S[5][x(0x4)] ^ S[6][x(0xA)] ^ S[7][x(0xB)] ^ S[7][x(0x7)]; 00129 Z[0] = X[0] ^ S[4][x(0xD)] ^ S[5][x(0xF)] ^ S[6][x(0xC)] ^ S[7][x(0xE)] ^ S[6][x(0x8)]; 00130 Z[1] = X[2] ^ S[4][z(0x0)] ^ S[5][z(0x2)] ^ S[6][z(0x1)] ^ S[7][z(0x3)] ^ S[7][x(0xA)]; 00131 Z[2] = X[3] ^ S[4][z(0x7)] ^ S[5][z(0x6)] ^ S[6][z(0x5)] ^ S[7][z(0x4)] ^ S[4][x(0x9)]; 00132 Z[3] = X[1] ^ S[4][z(0xA)] ^ S[5][z(0x9)] ^ S[6][z(0xB)] ^ S[7][z(0x8)] ^ S[5][x(0xB)]; 00133 K[i+8] = S[4][z(0x3)] ^ S[5][z(0x2)] ^ S[6][z(0xC)] ^ S[7][z(0xD)] ^ S[4][z(0x9)]; 00134 K[i+9] = S[4][z(0x1)] ^ S[5][z(0x0)] ^ S[6][z(0xE)] ^ S[7][z(0xF)] ^ S[5][z(0xC)]; 00135 K[i+10] = S[4][z(0x7)] ^ S[5][z(0x6)] ^ S[6][z(0x8)] ^ S[7][z(0x9)] ^ S[6][z(0x2)]; 00136 K[i+11] = S[4][z(0x5)] ^ S[5][z(0x4)] ^ S[6][z(0xA)] ^ S[7][z(0xB)] ^ S[7][z(0x6)]; 00137 X[0] = Z[2] ^ S[4][z(0x5)] ^ S[5][z(0x7)] ^ S[6][z(0x4)] ^ S[7][z(0x6)] ^ S[6][z(0x0)]; 00138 X[1] = Z[0] ^ S[4][x(0x0)] ^ S[5][x(0x2)] ^ S[6][x(0x1)] ^ S[7][x(0x3)] ^ S[7][z(0x2)]; 00139 X[2] = Z[1] ^ S[4][x(0x7)] ^ S[5][x(0x6)] ^ S[6][x(0x5)] ^ S[7][x(0x4)] ^ S[4][z(0x1)]; 00140 X[3] = Z[3] ^ S[4][x(0xA)] ^ S[5][x(0x9)] ^ S[6][x(0xB)] ^ S[7][x(0x8)] ^ S[5][z(0x3)]; 00141 K[i+12] = S[4][x(0x8)] ^ S[5][x(0x9)] ^ S[6][x(0x7)] ^ S[7][x(0x6)] ^ S[4][x(0x3)]; 00142 K[i+13] = S[4][x(0xA)] ^ S[5][x(0xB)] ^ S[6][x(0x5)] ^ S[7][x(0x4)] ^ S[5][x(0x7)]; 00143 K[i+14] = S[4][x(0xC)] ^ S[5][x(0xD)] ^ S[6][x(0x3)] ^ S[7][x(0x2)] ^ S[6][x(0x8)]; 00144 K[i+15] = S[4][x(0xE)] ^ S[5][x(0xF)] ^ S[6][x(0x1)] ^ S[7][x(0x0)] ^ S[7][x(0xD)]; 00145 } 00146 00147 for (i=16; i<32; i++) 00148 K[i] &= 0x1f; 00149 } 00150 00151 // The following CAST-256 implementation was contributed by Leonard Janke 00152 00153 const word32 CAST256::Base::t_m[8][24]={ 00154 { 0x5a827999, 0xd151d6a1, 0x482133a9, 0xbef090b1, 0x35bfedb9, 0xac8f4ac1, 00155 0x235ea7c9, 0x9a2e04d1, 0x10fd61d9, 0x87ccbee1, 0xfe9c1be9, 0x756b78f1, 00156 0xec3ad5f9, 0x630a3301, 0xd9d99009, 0x50a8ed11, 0xc7784a19, 0x3e47a721, 00157 0xb5170429, 0x2be66131, 0xa2b5be39, 0x19851b41, 0x90547849, 0x0723d551}, 00158 { 0xc95c653a, 0x402bc242, 0xb6fb1f4a, 0x2dca7c52, 0xa499d95a, 0x1b693662, 00159 0x9238936a, 0x0907f072, 0x7fd74d7a, 0xf6a6aa82, 0x6d76078a, 0xe4456492, 00160 0x5b14c19a, 0xd1e41ea2, 0x48b37baa, 0xbf82d8b2, 0x365235ba, 0xad2192c2, 00161 0x23f0efca, 0x9ac04cd2, 0x118fa9da, 0x885f06e2, 0xff2e63ea, 0x75fdc0f2}, 00162 { 0x383650db, 0xaf05ade3, 0x25d50aeb, 0x9ca467f3, 0x1373c4fb, 0x8a432203, 00163 0x01127f0b, 0x77e1dc13, 0xeeb1391b, 0x65809623, 0xdc4ff32b, 0x531f5033, 00164 0xc9eead3b, 0x40be0a43, 0xb78d674b, 0x2e5cc453, 0xa52c215b, 0x1bfb7e63, 00165 0x92cadb6b, 0x099a3873, 0x8069957b, 0xf738f283, 0x6e084f8b, 0xe4d7ac93}, 00166 { 0xa7103c7c, 0x1ddf9984, 0x94aef68c, 0x0b7e5394, 0x824db09c, 0xf91d0da4, 00167 0x6fec6aac, 0xe6bbc7b4, 0x5d8b24bc, 0xd45a81c4, 0x4b29decc, 0xc1f93bd4, 00168 0x38c898dc, 0xaf97f5e4, 0x266752ec, 0x9d36aff4, 0x14060cfc, 0x8ad56a04, 00169 0x01a4c70c, 0x78742414, 0xef43811c, 0x6612de24, 0xdce23b2c, 0x53b19834}, 00170 { 0x15ea281d, 0x8cb98525, 0x0388e22d, 0x7a583f35, 0xf1279c3d, 0x67f6f945, 00171 0xdec6564d, 0x5595b355, 0xcc65105d, 0x43346d65, 0xba03ca6d, 0x30d32775, 00172 0xa7a2847d, 0x1e71e185, 0x95413e8d, 0x0c109b95, 0x82dff89d, 0xf9af55a5, 00173 0x707eb2ad, 0xe74e0fb5, 0x5e1d6cbd, 0xd4ecc9c5, 0x4bbc26cd, 0xc28b83d5}, 00174 { 0x84c413be, 0xfb9370c6, 0x7262cdce, 0xe9322ad6, 0x600187de, 0xd6d0e4e6, 00175 0x4da041ee, 0xc46f9ef6, 0x3b3efbfe, 0xb20e5906, 0x28ddb60e, 0x9fad1316, 00176 0x167c701e, 0x8d4bcd26, 0x041b2a2e, 0x7aea8736, 0xf1b9e43e, 0x68894146, 00177 0xdf589e4e, 0x5627fb56, 0xccf7585e, 0x43c6b566, 0xba96126e, 0x31656f76}, 00178 { 0xf39dff5f, 0x6a6d5c67, 0xe13cb96f, 0x580c1677, 0xcedb737f, 0x45aad087, 00179 0xbc7a2d8f, 0x33498a97, 0xaa18e79f, 0x20e844a7, 0x97b7a1af, 0x0e86feb7, 00180 0x85565bbf, 0xfc25b8c7, 0x72f515cf, 0xe9c472d7, 0x6093cfdf, 0xd7632ce7, 00181 0x4e3289ef, 0xc501e6f7, 0x3bd143ff, 0xb2a0a107, 0x296ffe0f, 0xa03f5b17}, 00182 { 0x6277eb00, 0xd9474808, 0x5016a510, 0xc6e60218, 0x3db55f20, 0xb484bc28, 00183 0x2b541930, 0xa2237638, 0x18f2d340, 0x8fc23048, 0x06918d50, 0x7d60ea58, 00184 0xf4304760, 0x6affa468, 0xe1cf0170, 0x589e5e78, 0xcf6dbb80, 0x463d1888, 00185 0xbd0c7590, 0x33dbd298, 0xaaab2fa0, 0x217a8ca8, 0x9849e9b0, 0x0f1946b8} 00186 }; 00187 00188 const unsigned int CAST256::Base::t_r[8][24]={ 00189 {19, 27, 3, 11, 19, 27, 3, 11, 19, 27, 3, 11, 19, 27, 3, 11, 19, 27, 3, 11, 19, 27, 3, 11}, 00190 {4, 12, 20, 28, 4, 12, 20, 28, 4, 12, 20, 28, 4, 12, 20, 28, 4, 12, 20, 28, 4, 12, 20, 28}, 00191 {21, 29, 5, 13, 21, 29, 5, 13, 21, 29, 5, 13, 21, 29, 5, 13, 21, 29, 5, 13, 21, 29, 5, 13}, 00192 {6, 14, 22, 30, 6, 14, 22, 30, 6, 14, 22, 30, 6, 14, 22, 30, 6, 14, 22, 30, 6, 14, 22, 30}, 00193 {23, 31, 7, 15, 23, 31, 7, 15, 23, 31, 7, 15, 23, 31, 7, 15, 23, 31, 7, 15, 23, 31, 7, 15}, 00194 {8, 16, 24, 0, 8, 16, 24, 0, 8, 16, 24, 0, 8, 16, 24, 0, 8, 16, 24, 0, 8, 16, 24, 0}, 00195 {25, 1, 9, 17, 25, 1, 9, 17, 25, 1, 9, 17, 25, 1, 9, 17, 25, 1, 9, 17, 25, 1, 9, 17}, 00196 {10, 18, 26, 2, 10, 18, 26, 2, 10, 18, 26, 2, 10, 18, 26, 2, 10, 18, 26, 2, 10, 18, 26, 2} 00197 }; 00198 00199 #define Q(i) \ 00200 F1(block[2],block[3],8*i+4,-4); \ 00201 F2(block[1],block[2],8*i+5,-4); \ 00202 F3(block[0],block[1],8*i+6,-4); \ 00203 F1(block[3],block[0],8*i+7,-4); 00204 00205 #define QBar(i) \ 00206 F1(block[3],block[0],8*i+7,-4); \ 00207 F3(block[0],block[1],8*i+6,-4); \ 00208 F2(block[1],block[2],8*i+5,-4); \ 00209 F1(block[2],block[3],8*i+4,-4); 00210 00211 /* CAST256's encrypt/decrypt functions are identical except for the order that 00212 the keys are used */ 00213 00214 void CAST256::Base::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const 00215 { 00216 word32 t, block[4]; 00217 Block::Get(inBlock)(block[0])(block[1])(block[2])(block[3]); 00218 00219 // Perform 6 forward quad rounds 00220 Q(0); 00221 Q(1); 00222 Q(2); 00223 Q(3); 00224 Q(4); 00225 Q(5); 00226 00227 // Perform 6 reverse quad rounds 00228 QBar(6); 00229 QBar(7); 00230 QBar(8); 00231 QBar(9); 00232 QBar(10); 00233 QBar(11); 00234 00235 Block::Put(xorBlock, outBlock)(block[0])(block[1])(block[2])(block[3]); 00236 } 00237 00238 /* Set up a CAST-256 key */ 00239 00240 void CAST256::Base::Omega(int i, word32 kappa[8]) 00241 { 00242 word32 t; 00243 00244 f1(kappa[6],kappa[7],t_m[0][i],t_r[0][i]); 00245 f2(kappa[5],kappa[6],t_m[1][i],t_r[1][i]); 00246 f3(kappa[4],kappa[5],t_m[2][i],t_r[2][i]); 00247 f1(kappa[3],kappa[4],t_m[3][i],t_r[3][i]); 00248 f2(kappa[2],kappa[3],t_m[4][i],t_r[4][i]); 00249 f3(kappa[1],kappa[2],t_m[5][i],t_r[5][i]); 00250 f1(kappa[0],kappa[1],t_m[6][i],t_r[6][i]); 00251 f2(kappa[7],kappa[0],t_m[7][i],t_r[7][i]); 00252 } 00253 00254 void CAST256::Base::UncheckedSetKey(const byte *userKey, unsigned int keylength, const NameValuePairs &) 00255 { 00256 AssertValidKeyLength(keylength); 00257 00258 word32 kappa[8]; 00259 GetUserKey(BIG_ENDIAN_ORDER, kappa, 8, userKey, keylength); 00260 00261 for(int i=0; i<12; ++i) 00262 { 00263 Omega(2*i,kappa); 00264 Omega(2*i+1,kappa); 00265 00266 K[8*i]=kappa[0] & 31; 00267 K[8*i+1]=kappa[2] & 31; 00268 K[8*i+2]=kappa[4] & 31; 00269 K[8*i+3]=kappa[6] & 31; 00270 K[8*i+4]=kappa[7]; 00271 K[8*i+5]=kappa[5]; 00272 K[8*i+6]=kappa[3]; 00273 K[8*i+7]=kappa[1]; 00274 } 00275 00276 if (!IsForwardTransformation()) 00277 { 00278 for(int j=0; j<6; ++j) 00279 { 00280 for(int i=0; i<4; ++i) 00281 { 00282 int i1=8*j+i; 00283 int i2=8*(11-j)+i; 00284 00285 assert(i1<i2); 00286 00287 std::swap(K[i1],K[i2]); 00288 std::swap(K[i1+4],K[i2+4]); 00289 } 00290 } 00291 } 00292 00293 memset(kappa, 0, sizeof(kappa)); 00294 } 00295 00296 NAMESPACE_END