/* rijndael - An implementation of the Rijndael cipher. * * Copyright (C) 2000 Rafael R. Sevilla * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the Free * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include "rijndael.h" #include #include #include #include /* These tables combine both the S-boxes and the mixcolumn transformation, so that we can perform a round's encryption or by means of four table lookups and four XOR's per column of state. They were generated by the makertbls.pl script. */ static const UINT32 dtbl[] = { 0xa56363c6, 0x847c7cf8, 0x997777ee, 0x8d7b7bf6, 0x0df2f2ff, 0xbd6b6bd6, 0xb16f6fde, 0x54c5c591, 0x50303060, 0x03010102, 0xa96767ce, 0x7d2b2b56, 0x19fefee7, 0x62d7d7b5, 0xe6abab4d, 0x9a7676ec, 0x45caca8f, 0x9d82821f, 0x40c9c989, 0x877d7dfa, 0x15fafaef, 0xeb5959b2, 0xc947478e, 0x0bf0f0fb, 0xecadad41, 0x67d4d4b3, 0xfda2a25f, 0xeaafaf45, 0xbf9c9c23, 0xf7a4a453, 0x967272e4, 0x5bc0c09b, 0xc2b7b775, 0x1cfdfde1, 0xae93933d, 0x6a26264c, 0x5a36366c, 0x413f3f7e, 0x02f7f7f5, 0x4fcccc83, 0x5c343468, 0xf4a5a551, 0x34e5e5d1, 0x08f1f1f9, 0x937171e2, 0x73d8d8ab, 0x53313162, 0x3f15152a, 0x0c040408, 0x52c7c795, 0x65232346, 0x5ec3c39d, 0x28181830, 0xa1969637, 0x0f05050a, 0xb59a9a2f, 0x0907070e, 0x36121224, 0x9b80801b, 0x3de2e2df, 0x26ebebcd, 0x6927274e, 0xcdb2b27f, 0x9f7575ea, 0x1b090912, 0x9e83831d, 0x742c2c58, 0x2e1a1a34, 0x2d1b1b36, 0xb26e6edc, 0xee5a5ab4, 0xfba0a05b, 0xf65252a4, 0x4d3b3b76, 0x61d6d6b7, 0xceb3b37d, 0x7b292952, 0x3ee3e3dd, 0x712f2f5e, 0x97848413, 0xf55353a6, 0x68d1d1b9, 0x00000000, 0x2cededc1, 0x60202040, 0x1ffcfce3, 0xc8b1b179, 0xed5b5bb6, 0xbe6a6ad4, 0x46cbcb8d, 0xd9bebe67, 0x4b393972, 0xde4a4a94, 0xd44c4c98, 0xe85858b0, 0x4acfcf85, 0x6bd0d0bb, 0x2aefefc5, 0xe5aaaa4f, 0x16fbfbed, 0xc5434386, 0xd74d4d9a, 0x55333366, 0x94858511, 0xcf45458a, 0x10f9f9e9, 0x06020204, 0x817f7ffe, 0xf05050a0, 0x443c3c78, 0xba9f9f25, 0xe3a8a84b, 0xf35151a2, 0xfea3a35d, 0xc0404080, 0x8a8f8f05, 0xad92923f, 0xbc9d9d21, 0x48383870, 0x04f5f5f1, 0xdfbcbc63, 0xc1b6b677, 0x75dadaaf, 0x63212142, 0x30101020, 0x1affffe5, 0x0ef3f3fd, 0x6dd2d2bf, 0x4ccdcd81, 0x140c0c18, 0x35131326, 0x2fececc3, 0xe15f5fbe, 0xa2979735, 0xcc444488, 0x3917172e, 0x57c4c493, 0xf2a7a755, 0x827e7efc, 0x473d3d7a, 0xac6464c8, 0xe75d5dba, 0x2b191932, 0x957373e6, 0xa06060c0, 0x98818119, 0xd14f4f9e, 0x7fdcdca3, 0x66222244, 0x7e2a2a54, 0xab90903b, 0x8388880b, 0xca46468c, 0x29eeeec7, 0xd3b8b86b, 0x3c141428, 0x79dedea7, 0xe25e5ebc, 0x1d0b0b16, 0x76dbdbad, 0x3be0e0db, 0x56323264, 0x4e3a3a74, 0x1e0a0a14, 0xdb494992, 0x0a06060c, 0x6c242448, 0xe45c5cb8, 0x5dc2c29f, 0x6ed3d3bd, 0xefacac43, 0xa66262c4, 0xa8919139, 0xa4959531, 0x37e4e4d3, 0x8b7979f2, 0x32e7e7d5, 0x43c8c88b, 0x5937376e, 0xb76d6dda, 0x8c8d8d01, 0x64d5d5b1, 0xd24e4e9c, 0xe0a9a949, 0xb46c6cd8, 0xfa5656ac, 0x07f4f4f3, 0x25eaeacf, 0xaf6565ca, 0x8e7a7af4, 0xe9aeae47, 0x18080810, 0xd5baba6f, 0x887878f0, 0x6f25254a, 0x722e2e5c, 0x241c1c38, 0xf1a6a657, 0xc7b4b473, 0x51c6c697, 0x23e8e8cb, 0x7cdddda1, 0x9c7474e8, 0x211f1f3e, 0xdd4b4b96, 0xdcbdbd61, 0x868b8b0d, 0x858a8a0f, 0x907070e0, 0x423e3e7c, 0xc4b5b571, 0xaa6666cc, 0xd8484890, 0x05030306, 0x01f6f6f7, 0x120e0e1c, 0xa36161c2, 0x5f35356a, 0xf95757ae, 0xd0b9b969, 0x91868617, 0x58c1c199, 0x271d1d3a, 0xb99e9e27, 0x38e1e1d9, 0x13f8f8eb, 0xb398982b, 0x33111122, 0xbb6969d2, 0x70d9d9a9, 0x898e8e07, 0xa7949433, 0xb69b9b2d, 0x221e1e3c, 0x92878715, 0x20e9e9c9, 0x49cece87, 0xff5555aa, 0x78282850, 0x7adfdfa5, 0x8f8c8c03, 0xf8a1a159, 0x80898909, 0x170d0d1a, 0xdabfbf65, 0x31e6e6d7, 0xc6424284, 0xb86868d0, 0xc3414182, 0xb0999929, 0x772d2d5a, 0x110f0f1e, 0xcbb0b07b, 0xfc5454a8, 0xd6bbbb6d, 0x3a16162c, }; static const UINT32 itbl[] = { 0x50a7f451, 0x5365417e, 0xc3a4171a, 0x965e273a, 0xcb6bab3b, 0xf1459d1f, 0xab58faac, 0x9303e34b, 0x55fa3020, 0xf66d76ad, 0x9176cc88, 0x254c02f5, 0xfcd7e54f, 0xd7cb2ac5, 0x80443526, 0x8fa362b5, 0x495ab1de, 0x671bba25, 0x980eea45, 0xe1c0fe5d, 0x02752fc3, 0x12f04c81, 0xa397468d, 0xc6f9d36b, 0xe75f8f03, 0x959c9215, 0xeb7a6dbf, 0xda595295, 0x2d83bed4, 0xd3217458, 0x2969e049, 0x44c8c98e, 0x6a89c275, 0x78798ef4, 0x6b3e5899, 0xdd71b927, 0xb64fe1be, 0x17ad88f0, 0x66ac20c9, 0xb43ace7d, 0x184adf63, 0x82311ae5, 0x60335197, 0x457f5362, 0xe07764b1, 0x84ae6bbb, 0x1ca081fe, 0x942b08f9, 0x58684870, 0x19fd458f, 0x876cde94, 0xb7f87b52, 0x23d373ab, 0xe2024b72, 0x578f1fe3, 0x2aab5566, 0x0728ebb2, 0x03c2b52f, 0x9a7bc586, 0xa50837d3, 0xf2872830, 0xb2a5bf23, 0xba6a0302, 0x5c8216ed, 0x2b1ccf8a, 0x92b479a7, 0xf0f207f3, 0xa1e2694e, 0xcdf4da65, 0xd5be0506, 0x1f6234d1, 0x8afea6c4, 0x9d532e34, 0xa055f3a2, 0x32e18a05, 0x75ebf6a4, 0x39ec830b, 0xaaef6040, 0x069f715e, 0x51106ebd, 0xf98a213e, 0x3d06dd96, 0xae053edd, 0x46bde64d, 0xb58d5491, 0x055dc471, 0x6fd40604, 0xff155060, 0x24fb9819, 0x97e9bdd6, 0xcc434089, 0x779ed967, 0xbd42e8b0, 0x888b8907, 0x385b19e7, 0xdbeec879, 0x470a7ca1, 0xe90f427c, 0xc91e84f8, 0x00000000, 0x83868009, 0x48ed2b32, 0xac70111e, 0x4e725a6c, 0xfbff0efd, 0x5638850f, 0x1ed5ae3d, 0x27392d36, 0x64d90f0a, 0x21a65c68, 0xd1545b9b, 0x3a2e3624, 0xb1670a0c, 0x0fe75793, 0xd296eeb4, 0x9e919b1b, 0x4fc5c080, 0xa220dc61, 0x694b775a, 0x161a121c, 0x0aba93e2, 0xe52aa0c0, 0x43e0223c, 0x1d171b12, 0x0b0d090e, 0xadc78bf2, 0xb9a8b62d, 0xc8a91e14, 0x8519f157, 0x4c0775af, 0xbbdd99ee, 0xfd607fa3, 0x9f2601f7, 0xbcf5725c, 0xc53b6644, 0x347efb5b, 0x7629438b, 0xdcc623cb, 0x68fcedb6, 0x63f1e4b8, 0xcadc31d7, 0x10856342, 0x40229713, 0x2011c684, 0x7d244a85, 0xf83dbbd2, 0x1132f9ae, 0x6da129c7, 0x4b2f9e1d, 0xf330b2dc, 0xec52860d, 0xd0e3c177, 0x6c16b32b, 0x99b970a9, 0xfa489411, 0x2264e947, 0xc48cfca8, 0x1a3ff0a0, 0xd82c7d56, 0xef903322, 0xc74e4987, 0xc1d138d9, 0xfea2ca8c, 0x360bd498, 0xcf81f5a6, 0x28de7aa5, 0x268eb7da, 0xa4bfad3f, 0xe49d3a2c, 0x0d927850, 0x9bcc5f6a, 0x62467e54, 0xc2138df6, 0xe8b8d890, 0x5ef7392e, 0xf5afc382, 0xbe805d9f, 0x7c93d069, 0xa92dd56f, 0xb31225cf, 0x3b99acc8, 0xa77d1810, 0x6e639ce8, 0x7bbb3bdb, 0x097826cd, 0xf418596e, 0x01b79aec, 0xa89a4f83, 0x656e95e6, 0x7ee6ffaa, 0x08cfbc21, 0xe6e815ef, 0xd99be7ba, 0xce366f4a, 0xd4099fea, 0xd67cb029, 0xafb2a431, 0x31233f2a, 0x3094a5c6, 0xc066a235, 0x37bc4e74, 0xa6ca82fc, 0xb0d090e0, 0x15d8a733, 0x4a9804f1, 0xf7daec41, 0x0e50cd7f, 0x2ff69117, 0x8dd64d76, 0x4db0ef43, 0x544daacc, 0xdf0496e4, 0xe3b5d19e, 0x1b886a4c, 0xb81f2cc1, 0x7f516546, 0x04ea5e9d, 0x5d358c01, 0x737487fa, 0x2e410bfb, 0x5a1d67b3, 0x52d2db92, 0x335610e9, 0x1347d66d, 0x8c61d79a, 0x7a0ca137, 0x8e14f859, 0x893c13eb, 0xee27a9ce, 0x35c961b7, 0xede51ce1, 0x3cb1477a, 0x59dfd29c, 0x3f73f255, 0x79ce1418, 0xbf37c773, 0xeacdf753, 0x5baafd5f, 0x146f3ddf, 0x86db4478, 0x81f3afca, 0x3ec468b9, 0x2c342438, 0x5f40a3c2, 0x72c31d16, 0x0c25e2bc, 0x8b493c28, 0x41950dff, 0x7101a839, 0xdeb30c08, 0x9ce4b4d8, 0x90c15664, 0x6184cb7b, 0x70b632d5, 0x745c6c48, 0x4257b8d0, }; /* Needed only for the key schedule and for final rounds */ static const UINT8 sbox[256] = { 99, 124, 119, 123, 242, 107, 111, 197, 48, 1, 103, 43, 254, 215, 171, 118, 202, 130, 201, 125, 250, 89, 71, 240, 173, 212, 162, 175, 156, 164, 114, 192, 183, 253, 147, 38, 54, 63, 247, 204, 52, 165, 229, 241, 113, 216, 49, 21, 4, 199, 35, 195, 24, 150, 5, 154, 7, 18, 128, 226, 235, 39, 178, 117, 9, 131, 44, 26, 27, 110, 90, 160, 82, 59, 214, 179, 41, 227, 47, 132, 83, 209, 0, 237, 32, 252, 177, 91, 106, 203, 190, 57, 74, 76, 88, 207, 208, 239, 170, 251, 67, 77, 51, 133, 69, 249, 2, 127, 80, 60, 159, 168, 81, 163, 64, 143, 146, 157, 56, 245, 188, 182, 218, 33, 16, 255, 243, 210, 205, 12, 19, 236, 95, 151, 68, 23, 196, 167, 126, 61, 100, 93, 25, 115, 96, 129, 79, 220, 34, 42, 144, 136, 70, 238, 184, 20, 222, 94, 11, 219, 224, 50, 58, 10, 73, 6, 36, 92, 194, 211, 172, 98, 145, 149, 228, 121, 231, 200, 55, 109, 141, 213, 78, 169, 108, 86, 244, 234, 101, 122, 174, 8, 186, 120, 37, 46, 28, 166, 180, 198, 232, 221, 116, 31, 75, 189, 139, 138, 112, 62, 181, 102, 72, 3, 246, 14, 97, 53, 87, 185, 134, 193, 29, 158, 225, 248, 152, 17, 105, 217, 142, 148, 155, 30, 135, 233, 206, 85, 40, 223, 140, 161, 137, 13, 191, 230, 66, 104, 65, 153, 45, 15, 176, 84, 187, 22, }; static const UINT8 isbox[256] = { 82, 9, 106, 213, 48, 54, 165, 56, 191, 64, 163, 158, 129, 243, 215, 251, 124, 227, 57, 130, 155, 47, 255, 135, 52, 142, 67, 68, 196, 222, 233, 203, 84, 123, 148, 50, 166, 194, 35, 61, 238, 76, 149, 11, 66, 250, 195, 78, 8, 46, 161, 102, 40, 217, 36, 178, 118, 91, 162, 73, 109, 139, 209, 37, 114, 248, 246, 100, 134, 104, 152, 22, 212, 164, 92, 204, 93, 101, 182, 146, 108, 112, 72, 80, 253, 237, 185, 218, 94, 21, 70, 87, 167, 141, 157, 132, 144, 216, 171, 0, 140, 188, 211, 10, 247, 228, 88, 5, 184, 179, 69, 6, 208, 44, 30, 143, 202, 63, 15, 2, 193, 175, 189, 3, 1, 19, 138, 107, 58, 145, 17, 65, 79, 103, 220, 234, 151, 242, 207, 206, 240, 180, 230, 115, 150, 172, 116, 34, 231, 173, 53, 133, 226, 249, 55, 232, 28, 117, 223, 110, 71, 241, 26, 113, 29, 41, 197, 137, 111, 183, 98, 14, 170, 24, 190, 27, 252, 86, 62, 75, 198, 210, 121, 32, 154, 219, 192, 254, 120, 205, 90, 244, 31, 221, 168, 51, 136, 7, 199, 49, 177, 18, 16, 89, 39, 128, 236, 95, 96, 81, 127, 169, 25, 181, 74, 13, 45, 229, 122, 159, 147, 201, 156, 239, 160, 224, 59, 77, 174, 42, 245, 176, 200, 235, 187, 60, 131, 83, 153, 97, 23, 43, 4, 126, 186, 119, 214, 38, 225, 105, 20, 99, 85, 33, 12, 125, }; /* Used only by the key schedule */ static const UINT8 Logtable[256] = { 0, 0, 25, 1, 50, 2, 26, 198, 75, 199, 27, 104, 51, 238, 223, 3, 100, 4, 224, 14, 52, 141, 129, 239, 76, 113, 8, 200, 248, 105, 28, 193, 125, 194, 29, 181, 249, 185, 39, 106, 77, 228, 166, 114, 154, 201, 9, 120, 101, 47, 138, 5, 33, 15, 225, 36, 18, 240, 130, 69, 53, 147, 218, 142, 150, 143, 219, 189, 54, 208, 206, 148, 19, 92, 210, 241, 64, 70, 131, 56, 102, 221, 253, 48, 191, 6, 139, 98, 179, 37, 226, 152, 34, 136, 145, 16, 126, 110, 72, 195, 163, 182, 30, 66, 58, 107, 40, 84, 250, 133, 61, 186, 43, 121, 10, 21, 155, 159, 94, 202, 78, 212, 172, 229, 243, 115, 167, 87, 175, 88, 168, 80, 244, 234, 214, 116, 79, 174, 233, 213, 231, 230, 173, 232, 44, 215, 117, 122, 235, 22, 11, 245, 89, 203, 95, 176, 156, 169, 81, 160, 127, 12, 246, 111, 23, 196, 73, 236, 216, 67, 31, 45, 164, 118, 123, 183, 204, 187, 62, 90, 251, 96, 177, 134, 59, 82, 161, 108, 170, 85, 41, 157, 151, 178, 135, 144, 97, 190, 220, 252, 188, 149, 207, 205, 55, 63, 91, 209, 83, 57, 132, 60, 65, 162, 109, 71, 20, 42, 158, 93, 86, 242, 211, 171, 68, 17, 146, 217, 35, 32, 46, 137, 180, 124, 184, 38, 119, 153, 227, 165, 103, 74, 237, 222, 197, 49, 254, 24, 13, 99, 140, 128, 192, 247, 112, 7, }; static const UINT8 Alogtable[256] = { 1, 3, 5, 15, 17, 51, 85, 255, 26, 46, 114, 150, 161, 248, 19, 53, 95, 225, 56, 72, 216, 115, 149, 164, 247, 2, 6, 10, 30, 34, 102, 170, 229, 52, 92, 228, 55, 89, 235, 38, 106, 190, 217, 112, 144, 171, 230, 49, 83, 245, 4, 12, 20, 60, 68, 204, 79, 209, 104, 184, 211, 110, 178, 205, 76, 212, 103, 169, 224, 59, 77, 215, 98, 166, 241, 8, 24, 40, 120, 136, 131, 158, 185, 208, 107, 189, 220, 127, 129, 152, 179, 206, 73, 219, 118, 154, 181, 196, 87, 249, 16, 48, 80, 240, 11, 29, 39, 105, 187, 214, 97, 163, 254, 25, 43, 125, 135, 146, 173, 236, 47, 113, 147, 174, 233, 32, 96, 160, 251, 22, 58, 78, 210, 109, 183, 194, 93, 231, 50, 86, 250, 21, 63, 65, 195, 94, 226, 61, 71, 201, 64, 192, 91, 237, 44, 116, 156, 191, 218, 117, 159, 186, 213, 100, 172, 239, 42, 126, 130, 157, 188, 223, 122, 142, 137, 128, 155, 182, 193, 88, 232, 35, 101, 175, 234, 37, 111, 177, 200, 67, 197, 84, 252, 31, 33, 99, 165, 244, 7, 9, 27, 45, 119, 153, 176, 203, 70, 202, 69, 207, 74, 222, 121, 139, 134, 145, 168, 227, 62, 66, 198, 81, 243, 14, 18, 54, 90, 238, 41, 123, 141, 140, 143, 138, 133, 148, 167, 242, 13, 23, 57, 75, 221, 124, 132, 151, 162, 253, 28, 36, 108, 180, 199, 82, 246, 1, }; #define ROTBYTE(x) (((x) >> 8) | (((x) & 0xff) << 24)) #define ROTRBYTE(x) (((x) << 8) | (((x) >> 24) & 0xff)) #define SUBBYTE(x, box) (((box)[((x) & 0xff)]) | \ ((box)[(((x) >> 8) & 0xff)] << 8) | \ ((box)[(((x) >> 16) & 0xff)] << 16) | \ ((box)[(((x) >> 24) & 0xff)] << 24)) static UINT8 xtime(UINT8 a) { UINT8 b; b = (a & 0x80) ? 0x1b : 0; a<<=1; a^=b; return(a); } static UINT8 mul(UINT8 a, UINT8 b) { if (a && b) return Alogtable[(Logtable[a] + Logtable[b])%255]; else return 0; } static void inv_mix_column(UINT32 *a, UINT32 *b) { UINT8 c[4][4]; int i, j; for(j = 0; j < 4; j++) { for(i = 0; i < 4; i++) { c[j][i] = mul(0xe, (a[j] >> i*8) & 0xff) ^ mul(0xb, (a[j] >> ((i+1)%4)*8) & 0xff) ^ mul(0xd, (a[j] >> ((i+2)%4)*8) & 0xff) ^ mul(0x9, (a[j] >> ((i+3)%4)*8) & 0xff); } } for(i = 0; i < 4; i++) { b[i] = 0; for(j = 0; j < 4; j++) b[i] |= c[i][j] << (j*8); } } void rijndael_setup(RIJNDAEL_context *ctx, size_t keysize, const UINT8 *key) { int nk, nr, i, lastkey; UINT32 temp, rcon; /* Truncate keysizes to the valid key sizes provided by Rijndael */ if (keysize >= 32) { nk = 8; nr = 14; } else if (keysize >= 24) { nk = 6; nr = 12; } else { /* must be 16 or more */ assert(keysize >= 16); nk = 4; nr = 10; } lastkey = (RIJNDAEL_BLOCKSIZE/4) * (nr + 1); ctx->nrounds = nr; rcon = 1; for (i=0; ikeys[i] = key[i*4] + (key[i*4+1]<<8) + (key[i*4+2]<<16) + (key[i*4+3]<<24); } for (i=nk; ikeys[i-1]; if (i % nk == 0) { temp = SUBBYTE(ROTBYTE(temp), sbox) ^ rcon; rcon = (UINT32)xtime((UINT8)rcon&0xff); } else if (nk > 6 && (i%nk) == 4) { temp = SUBBYTE(temp, sbox); } ctx->keys[i] = ctx->keys[i-nk] ^ temp; } /* Generate the inverse keys */ for (i=0; i<4; i++) { ctx->ikeys[i] = ctx->keys[i]; ctx->ikeys[lastkey-4 + i] = ctx->keys[lastkey-4 + i]; } for (i=4; ikeys[i]), &(ctx->ikeys[i])); } /* Key addition that also packs every byte in the key to a word rep. */ static void key_addition_8to32(const UINT8 *txt, UINT32 *keys, UINT32 *out) { const UINT8 *ptr; int i, j; UINT32 val; ptr = txt; for (i=0; i<4; i++) { val = 0; for (j=0; j<4; j++) val |= (*ptr++ << 8*j); out[i] = keys[i]^val; } } static void key_addition32(const UINT32 *txt, UINT32 *keys, UINT32 *out) { int i; for (i=0; i<4; i++) out[i] = keys[i] ^ txt[i]; } static void key_addition32to8(const UINT32 *txt, UINT32 *keys, UINT8 *out) { UINT8 *ptr; int i, j; UINT32 val; ptr = out; for (i=0; i<4; i++) { val = txt[i] ^ keys[i]; for (j=0; j<4; j++) *ptr++ = (val >> 8*j) & 0xff; } } static const int idx[4][4] = { { 0, 1, 2, 3 }, { 1, 2, 3, 0 }, { 2, 3, 0, 1 }, { 3, 0, 1, 2 } }; void rijndael_encrypt(RIJNDAEL_context *ctx, const UINT8 *plaintext, UINT8 *ciphertext) { int r, j; UINT32 wtxt[4], t[4]; /* working ciphertext */ UINT32 e; key_addition_8to32(plaintext, &(ctx->keys[0]), wtxt); for (r=1; rnrounds; r++) { for (j=0; j<4; j++) { t[j] = dtbl[wtxt[j] & 0xff] ^ ROTRBYTE(dtbl[(wtxt[idx[1][j]] >> 8) & 0xff]^ ROTRBYTE(dtbl[(wtxt[idx[2][j]] >> 16) & 0xff] ^ ROTRBYTE(dtbl[(wtxt[idx[3][j]] >> 24) & 0xff]))); } key_addition32(t, &(ctx->keys[r*4]), wtxt); } /* last round is special: there is no mixcolumn, so we can't use the big tables. */ for (j=0; j<4; j++) { e = wtxt[j] & 0xff; e |= (wtxt[idx[1][j]]) & (0xff << 8); e |= (wtxt[idx[2][j]]) & (0xff << 16); e |= (wtxt[idx[3][j]]) & (0xff << 24); t[j] = e; } for (j=0; j<4; j++) t[j] = SUBBYTE(t[j], sbox); key_addition32to8(t, &(ctx->keys[4*ctx->nrounds]), ciphertext); } static const int iidx[4][4] = { { 0, 1, 2, 3 }, { 3, 0, 1, 2 }, { 2, 3, 0, 1 }, { 1, 2, 3, 0 } }; void rijndael_decrypt(RIJNDAEL_context *ctx, const UINT8 *ciphertext, UINT8 *plaintext) { int r, j; UINT32 wtxt[4], t[4]; /* working ciphertext */ UINT32 e; key_addition_8to32(ciphertext, &(ctx->ikeys[4*ctx->nrounds]), wtxt); for (r=ctx->nrounds-1; r> 0; r--) { for (j=0; j<4; j++) { t[j] = itbl[wtxt[j] & 0xff] ^ ROTRBYTE(itbl[(wtxt[iidx[1][j]] >> 8) & 0xff]^ ROTRBYTE(itbl[(wtxt[iidx[2][j]] >> 16) & 0xff] ^ ROTRBYTE(itbl[(wtxt[iidx[3][j]] >> 24) & 0xff]))); } key_addition32(t, &(ctx->ikeys[r*4]), wtxt); } /* last round is special: there is no mixcolumn, so we can't use the big tables. */ for (j=0; j<4; j++) { e = wtxt[j] & 0xff; e |= (wtxt[iidx[1][j]]) & (0xff << 8); e |= (wtxt[iidx[2][j]]) & (0xff << 16); e |= (wtxt[iidx[3][j]]) & (0xff << 24); t[j] = e; } for (j=0; j<4; j++) t[j] = SUBBYTE(t[j], isbox); key_addition32to8(t, &(ctx->ikeys[0]), plaintext); }