001: package org.bouncycastle.crypto.engines;
002:
003: import org.bouncycastle.crypto.BlockCipher;
004: import org.bouncycastle.crypto.CipherParameters;
005: import org.bouncycastle.crypto.DataLengthException;
006: import org.bouncycastle.crypto.params.KeyParameter;
007:
008: /**
009: * an implementation of the AES (Rijndael), from FIPS-197.
010: * <p>
011: * For further details see: <a href="http://csrc.nist.gov/encryption/aes/">http://csrc.nist.gov/encryption/aes/</a>.
012: *
013: * This implementation is based on optimizations from Dr. Brian Gladman's paper and C code at
014: * <a href="http://fp.gladman.plus.com/cryptography_technology/rijndael/">http://fp.gladman.plus.com/cryptography_technology/rijndael/</a>
015: *
016: * There are three levels of tradeoff of speed vs memory
017: * Because java has no preprocessor, they are written as three separate classes from which to choose
018: *
019: * The fastest uses 8Kbytes of static tables to precompute round calculations, 4 256 word tables for encryption
020: * and 4 for decryption.
021: *
022: * The middle performance version uses only one 256 word table for each, for a total of 2Kbytes,
023: * adding 12 rotate operations per round to compute the values contained in the other tables from
024: * the contents of the first.
025: *
026: * The slowest version uses no static tables at all and computes the values in each round.
027: * <p>
028: * This file contains the middle performance version with 2Kbytes of static tables for round precomputation.
029: *
030: */
031: public class AESEngine implements BlockCipher {
032: // The S box
033: private static final byte[] S = { (byte) 99, (byte) 124,
034: (byte) 119, (byte) 123, (byte) 242, (byte) 107, (byte) 111,
035: (byte) 197, (byte) 48, (byte) 1, (byte) 103, (byte) 43,
036: (byte) 254, (byte) 215, (byte) 171, (byte) 118, (byte) 202,
037: (byte) 130, (byte) 201, (byte) 125, (byte) 250, (byte) 89,
038: (byte) 71, (byte) 240, (byte) 173, (byte) 212, (byte) 162,
039: (byte) 175, (byte) 156, (byte) 164, (byte) 114, (byte) 192,
040: (byte) 183, (byte) 253, (byte) 147, (byte) 38, (byte) 54,
041: (byte) 63, (byte) 247, (byte) 204, (byte) 52, (byte) 165,
042: (byte) 229, (byte) 241, (byte) 113, (byte) 216, (byte) 49,
043: (byte) 21, (byte) 4, (byte) 199, (byte) 35, (byte) 195,
044: (byte) 24, (byte) 150, (byte) 5, (byte) 154, (byte) 7,
045: (byte) 18, (byte) 128, (byte) 226, (byte) 235, (byte) 39,
046: (byte) 178, (byte) 117, (byte) 9, (byte) 131, (byte) 44,
047: (byte) 26, (byte) 27, (byte) 110, (byte) 90, (byte) 160,
048: (byte) 82, (byte) 59, (byte) 214, (byte) 179, (byte) 41,
049: (byte) 227, (byte) 47, (byte) 132, (byte) 83, (byte) 209,
050: (byte) 0, (byte) 237, (byte) 32, (byte) 252, (byte) 177,
051: (byte) 91, (byte) 106, (byte) 203, (byte) 190, (byte) 57,
052: (byte) 74, (byte) 76, (byte) 88, (byte) 207, (byte) 208,
053: (byte) 239, (byte) 170, (byte) 251, (byte) 67, (byte) 77,
054: (byte) 51, (byte) 133, (byte) 69, (byte) 249, (byte) 2,
055: (byte) 127, (byte) 80, (byte) 60, (byte) 159, (byte) 168,
056: (byte) 81, (byte) 163, (byte) 64, (byte) 143, (byte) 146,
057: (byte) 157, (byte) 56, (byte) 245, (byte) 188, (byte) 182,
058: (byte) 218, (byte) 33, (byte) 16, (byte) 255, (byte) 243,
059: (byte) 210, (byte) 205, (byte) 12, (byte) 19, (byte) 236,
060: (byte) 95, (byte) 151, (byte) 68, (byte) 23, (byte) 196,
061: (byte) 167, (byte) 126, (byte) 61, (byte) 100, (byte) 93,
062: (byte) 25, (byte) 115, (byte) 96, (byte) 129, (byte) 79,
063: (byte) 220, (byte) 34, (byte) 42, (byte) 144, (byte) 136,
064: (byte) 70, (byte) 238, (byte) 184, (byte) 20, (byte) 222,
065: (byte) 94, (byte) 11, (byte) 219, (byte) 224, (byte) 50,
066: (byte) 58, (byte) 10, (byte) 73, (byte) 6, (byte) 36,
067: (byte) 92, (byte) 194, (byte) 211, (byte) 172, (byte) 98,
068: (byte) 145, (byte) 149, (byte) 228, (byte) 121, (byte) 231,
069: (byte) 200, (byte) 55, (byte) 109, (byte) 141, (byte) 213,
070: (byte) 78, (byte) 169, (byte) 108, (byte) 86, (byte) 244,
071: (byte) 234, (byte) 101, (byte) 122, (byte) 174, (byte) 8,
072: (byte) 186, (byte) 120, (byte) 37, (byte) 46, (byte) 28,
073: (byte) 166, (byte) 180, (byte) 198, (byte) 232, (byte) 221,
074: (byte) 116, (byte) 31, (byte) 75, (byte) 189, (byte) 139,
075: (byte) 138, (byte) 112, (byte) 62, (byte) 181, (byte) 102,
076: (byte) 72, (byte) 3, (byte) 246, (byte) 14, (byte) 97,
077: (byte) 53, (byte) 87, (byte) 185, (byte) 134, (byte) 193,
078: (byte) 29, (byte) 158, (byte) 225, (byte) 248, (byte) 152,
079: (byte) 17, (byte) 105, (byte) 217, (byte) 142, (byte) 148,
080: (byte) 155, (byte) 30, (byte) 135, (byte) 233, (byte) 206,
081: (byte) 85, (byte) 40, (byte) 223, (byte) 140, (byte) 161,
082: (byte) 137, (byte) 13, (byte) 191, (byte) 230, (byte) 66,
083: (byte) 104, (byte) 65, (byte) 153, (byte) 45, (byte) 15,
084: (byte) 176, (byte) 84, (byte) 187, (byte) 22, };
085:
086: // The inverse S-box
087: private static final byte[] Si = { (byte) 82, (byte) 9, (byte) 106,
088: (byte) 213, (byte) 48, (byte) 54, (byte) 165, (byte) 56,
089: (byte) 191, (byte) 64, (byte) 163, (byte) 158, (byte) 129,
090: (byte) 243, (byte) 215, (byte) 251, (byte) 124, (byte) 227,
091: (byte) 57, (byte) 130, (byte) 155, (byte) 47, (byte) 255,
092: (byte) 135, (byte) 52, (byte) 142, (byte) 67, (byte) 68,
093: (byte) 196, (byte) 222, (byte) 233, (byte) 203, (byte) 84,
094: (byte) 123, (byte) 148, (byte) 50, (byte) 166, (byte) 194,
095: (byte) 35, (byte) 61, (byte) 238, (byte) 76, (byte) 149,
096: (byte) 11, (byte) 66, (byte) 250, (byte) 195, (byte) 78,
097: (byte) 8, (byte) 46, (byte) 161, (byte) 102, (byte) 40,
098: (byte) 217, (byte) 36, (byte) 178, (byte) 118, (byte) 91,
099: (byte) 162, (byte) 73, (byte) 109, (byte) 139, (byte) 209,
100: (byte) 37, (byte) 114, (byte) 248, (byte) 246, (byte) 100,
101: (byte) 134, (byte) 104, (byte) 152, (byte) 22, (byte) 212,
102: (byte) 164, (byte) 92, (byte) 204, (byte) 93, (byte) 101,
103: (byte) 182, (byte) 146, (byte) 108, (byte) 112, (byte) 72,
104: (byte) 80, (byte) 253, (byte) 237, (byte) 185, (byte) 218,
105: (byte) 94, (byte) 21, (byte) 70, (byte) 87, (byte) 167,
106: (byte) 141, (byte) 157, (byte) 132, (byte) 144, (byte) 216,
107: (byte) 171, (byte) 0, (byte) 140, (byte) 188, (byte) 211,
108: (byte) 10, (byte) 247, (byte) 228, (byte) 88, (byte) 5,
109: (byte) 184, (byte) 179, (byte) 69, (byte) 6, (byte) 208,
110: (byte) 44, (byte) 30, (byte) 143, (byte) 202, (byte) 63,
111: (byte) 15, (byte) 2, (byte) 193, (byte) 175, (byte) 189,
112: (byte) 3, (byte) 1, (byte) 19, (byte) 138, (byte) 107,
113: (byte) 58, (byte) 145, (byte) 17, (byte) 65, (byte) 79,
114: (byte) 103, (byte) 220, (byte) 234, (byte) 151, (byte) 242,
115: (byte) 207, (byte) 206, (byte) 240, (byte) 180, (byte) 230,
116: (byte) 115, (byte) 150, (byte) 172, (byte) 116, (byte) 34,
117: (byte) 231, (byte) 173, (byte) 53, (byte) 133, (byte) 226,
118: (byte) 249, (byte) 55, (byte) 232, (byte) 28, (byte) 117,
119: (byte) 223, (byte) 110, (byte) 71, (byte) 241, (byte) 26,
120: (byte) 113, (byte) 29, (byte) 41, (byte) 197, (byte) 137,
121: (byte) 111, (byte) 183, (byte) 98, (byte) 14, (byte) 170,
122: (byte) 24, (byte) 190, (byte) 27, (byte) 252, (byte) 86,
123: (byte) 62, (byte) 75, (byte) 198, (byte) 210, (byte) 121,
124: (byte) 32, (byte) 154, (byte) 219, (byte) 192, (byte) 254,
125: (byte) 120, (byte) 205, (byte) 90, (byte) 244, (byte) 31,
126: (byte) 221, (byte) 168, (byte) 51, (byte) 136, (byte) 7,
127: (byte) 199, (byte) 49, (byte) 177, (byte) 18, (byte) 16,
128: (byte) 89, (byte) 39, (byte) 128, (byte) 236, (byte) 95,
129: (byte) 96, (byte) 81, (byte) 127, (byte) 169, (byte) 25,
130: (byte) 181, (byte) 74, (byte) 13, (byte) 45, (byte) 229,
131: (byte) 122, (byte) 159, (byte) 147, (byte) 201, (byte) 156,
132: (byte) 239, (byte) 160, (byte) 224, (byte) 59, (byte) 77,
133: (byte) 174, (byte) 42, (byte) 245, (byte) 176, (byte) 200,
134: (byte) 235, (byte) 187, (byte) 60, (byte) 131, (byte) 83,
135: (byte) 153, (byte) 97, (byte) 23, (byte) 43, (byte) 4,
136: (byte) 126, (byte) 186, (byte) 119, (byte) 214, (byte) 38,
137: (byte) 225, (byte) 105, (byte) 20, (byte) 99, (byte) 85,
138: (byte) 33, (byte) 12, (byte) 125, };
139:
140: // vector used in calculating key schedule (powers of x in GF(256))
141: private static final int[] rcon = { 0x01, 0x02, 0x04, 0x08, 0x10,
142: 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a,
143: 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3,
144: 0x7d, 0xfa, 0xef, 0xc5, 0x91 };
145:
146: // precomputation tables of calculations for rounds
147: private static final int[] T0 = { 0xa56363c6, 0x847c7cf8,
148: 0x997777ee, 0x8d7b7bf6, 0x0df2f2ff, 0xbd6b6bd6, 0xb16f6fde,
149: 0x54c5c591, 0x50303060, 0x03010102, 0xa96767ce, 0x7d2b2b56,
150: 0x19fefee7, 0x62d7d7b5, 0xe6abab4d, 0x9a7676ec, 0x45caca8f,
151: 0x9d82821f, 0x40c9c989, 0x877d7dfa, 0x15fafaef, 0xeb5959b2,
152: 0xc947478e, 0x0bf0f0fb, 0xecadad41, 0x67d4d4b3, 0xfda2a25f,
153: 0xeaafaf45, 0xbf9c9c23, 0xf7a4a453, 0x967272e4, 0x5bc0c09b,
154: 0xc2b7b775, 0x1cfdfde1, 0xae93933d, 0x6a26264c, 0x5a36366c,
155: 0x413f3f7e, 0x02f7f7f5, 0x4fcccc83, 0x5c343468, 0xf4a5a551,
156: 0x34e5e5d1, 0x08f1f1f9, 0x937171e2, 0x73d8d8ab, 0x53313162,
157: 0x3f15152a, 0x0c040408, 0x52c7c795, 0x65232346, 0x5ec3c39d,
158: 0x28181830, 0xa1969637, 0x0f05050a, 0xb59a9a2f, 0x0907070e,
159: 0x36121224, 0x9b80801b, 0x3de2e2df, 0x26ebebcd, 0x6927274e,
160: 0xcdb2b27f, 0x9f7575ea, 0x1b090912, 0x9e83831d, 0x742c2c58,
161: 0x2e1a1a34, 0x2d1b1b36, 0xb26e6edc, 0xee5a5ab4, 0xfba0a05b,
162: 0xf65252a4, 0x4d3b3b76, 0x61d6d6b7, 0xceb3b37d, 0x7b292952,
163: 0x3ee3e3dd, 0x712f2f5e, 0x97848413, 0xf55353a6, 0x68d1d1b9,
164: 0x00000000, 0x2cededc1, 0x60202040, 0x1ffcfce3, 0xc8b1b179,
165: 0xed5b5bb6, 0xbe6a6ad4, 0x46cbcb8d, 0xd9bebe67, 0x4b393972,
166: 0xde4a4a94, 0xd44c4c98, 0xe85858b0, 0x4acfcf85, 0x6bd0d0bb,
167: 0x2aefefc5, 0xe5aaaa4f, 0x16fbfbed, 0xc5434386, 0xd74d4d9a,
168: 0x55333366, 0x94858511, 0xcf45458a, 0x10f9f9e9, 0x06020204,
169: 0x817f7ffe, 0xf05050a0, 0x443c3c78, 0xba9f9f25, 0xe3a8a84b,
170: 0xf35151a2, 0xfea3a35d, 0xc0404080, 0x8a8f8f05, 0xad92923f,
171: 0xbc9d9d21, 0x48383870, 0x04f5f5f1, 0xdfbcbc63, 0xc1b6b677,
172: 0x75dadaaf, 0x63212142, 0x30101020, 0x1affffe5, 0x0ef3f3fd,
173: 0x6dd2d2bf, 0x4ccdcd81, 0x140c0c18, 0x35131326, 0x2fececc3,
174: 0xe15f5fbe, 0xa2979735, 0xcc444488, 0x3917172e, 0x57c4c493,
175: 0xf2a7a755, 0x827e7efc, 0x473d3d7a, 0xac6464c8, 0xe75d5dba,
176: 0x2b191932, 0x957373e6, 0xa06060c0, 0x98818119, 0xd14f4f9e,
177: 0x7fdcdca3, 0x66222244, 0x7e2a2a54, 0xab90903b, 0x8388880b,
178: 0xca46468c, 0x29eeeec7, 0xd3b8b86b, 0x3c141428, 0x79dedea7,
179: 0xe25e5ebc, 0x1d0b0b16, 0x76dbdbad, 0x3be0e0db, 0x56323264,
180: 0x4e3a3a74, 0x1e0a0a14, 0xdb494992, 0x0a06060c, 0x6c242448,
181: 0xe45c5cb8, 0x5dc2c29f, 0x6ed3d3bd, 0xefacac43, 0xa66262c4,
182: 0xa8919139, 0xa4959531, 0x37e4e4d3, 0x8b7979f2, 0x32e7e7d5,
183: 0x43c8c88b, 0x5937376e, 0xb76d6dda, 0x8c8d8d01, 0x64d5d5b1,
184: 0xd24e4e9c, 0xe0a9a949, 0xb46c6cd8, 0xfa5656ac, 0x07f4f4f3,
185: 0x25eaeacf, 0xaf6565ca, 0x8e7a7af4, 0xe9aeae47, 0x18080810,
186: 0xd5baba6f, 0x887878f0, 0x6f25254a, 0x722e2e5c, 0x241c1c38,
187: 0xf1a6a657, 0xc7b4b473, 0x51c6c697, 0x23e8e8cb, 0x7cdddda1,
188: 0x9c7474e8, 0x211f1f3e, 0xdd4b4b96, 0xdcbdbd61, 0x868b8b0d,
189: 0x858a8a0f, 0x907070e0, 0x423e3e7c, 0xc4b5b571, 0xaa6666cc,
190: 0xd8484890, 0x05030306, 0x01f6f6f7, 0x120e0e1c, 0xa36161c2,
191: 0x5f35356a, 0xf95757ae, 0xd0b9b969, 0x91868617, 0x58c1c199,
192: 0x271d1d3a, 0xb99e9e27, 0x38e1e1d9, 0x13f8f8eb, 0xb398982b,
193: 0x33111122, 0xbb6969d2, 0x70d9d9a9, 0x898e8e07, 0xa7949433,
194: 0xb69b9b2d, 0x221e1e3c, 0x92878715, 0x20e9e9c9, 0x49cece87,
195: 0xff5555aa, 0x78282850, 0x7adfdfa5, 0x8f8c8c03, 0xf8a1a159,
196: 0x80898909, 0x170d0d1a, 0xdabfbf65, 0x31e6e6d7, 0xc6424284,
197: 0xb86868d0, 0xc3414182, 0xb0999929, 0x772d2d5a, 0x110f0f1e,
198: 0xcbb0b07b, 0xfc5454a8, 0xd6bbbb6d, 0x3a16162c };
199:
200: private static final int[] Tinv0 = { 0x50a7f451, 0x5365417e,
201: 0xc3a4171a, 0x965e273a, 0xcb6bab3b, 0xf1459d1f, 0xab58faac,
202: 0x9303e34b, 0x55fa3020, 0xf66d76ad, 0x9176cc88, 0x254c02f5,
203: 0xfcd7e54f, 0xd7cb2ac5, 0x80443526, 0x8fa362b5, 0x495ab1de,
204: 0x671bba25, 0x980eea45, 0xe1c0fe5d, 0x02752fc3, 0x12f04c81,
205: 0xa397468d, 0xc6f9d36b, 0xe75f8f03, 0x959c9215, 0xeb7a6dbf,
206: 0xda595295, 0x2d83bed4, 0xd3217458, 0x2969e049, 0x44c8c98e,
207: 0x6a89c275, 0x78798ef4, 0x6b3e5899, 0xdd71b927, 0xb64fe1be,
208: 0x17ad88f0, 0x66ac20c9, 0xb43ace7d, 0x184adf63, 0x82311ae5,
209: 0x60335197, 0x457f5362, 0xe07764b1, 0x84ae6bbb, 0x1ca081fe,
210: 0x942b08f9, 0x58684870, 0x19fd458f, 0x876cde94, 0xb7f87b52,
211: 0x23d373ab, 0xe2024b72, 0x578f1fe3, 0x2aab5566, 0x0728ebb2,
212: 0x03c2b52f, 0x9a7bc586, 0xa50837d3, 0xf2872830, 0xb2a5bf23,
213: 0xba6a0302, 0x5c8216ed, 0x2b1ccf8a, 0x92b479a7, 0xf0f207f3,
214: 0xa1e2694e, 0xcdf4da65, 0xd5be0506, 0x1f6234d1, 0x8afea6c4,
215: 0x9d532e34, 0xa055f3a2, 0x32e18a05, 0x75ebf6a4, 0x39ec830b,
216: 0xaaef6040, 0x069f715e, 0x51106ebd, 0xf98a213e, 0x3d06dd96,
217: 0xae053edd, 0x46bde64d, 0xb58d5491, 0x055dc471, 0x6fd40604,
218: 0xff155060, 0x24fb9819, 0x97e9bdd6, 0xcc434089, 0x779ed967,
219: 0xbd42e8b0, 0x888b8907, 0x385b19e7, 0xdbeec879, 0x470a7ca1,
220: 0xe90f427c, 0xc91e84f8, 0x00000000, 0x83868009, 0x48ed2b32,
221: 0xac70111e, 0x4e725a6c, 0xfbff0efd, 0x5638850f, 0x1ed5ae3d,
222: 0x27392d36, 0x64d90f0a, 0x21a65c68, 0xd1545b9b, 0x3a2e3624,
223: 0xb1670a0c, 0x0fe75793, 0xd296eeb4, 0x9e919b1b, 0x4fc5c080,
224: 0xa220dc61, 0x694b775a, 0x161a121c, 0x0aba93e2, 0xe52aa0c0,
225: 0x43e0223c, 0x1d171b12, 0x0b0d090e, 0xadc78bf2, 0xb9a8b62d,
226: 0xc8a91e14, 0x8519f157, 0x4c0775af, 0xbbdd99ee, 0xfd607fa3,
227: 0x9f2601f7, 0xbcf5725c, 0xc53b6644, 0x347efb5b, 0x7629438b,
228: 0xdcc623cb, 0x68fcedb6, 0x63f1e4b8, 0xcadc31d7, 0x10856342,
229: 0x40229713, 0x2011c684, 0x7d244a85, 0xf83dbbd2, 0x1132f9ae,
230: 0x6da129c7, 0x4b2f9e1d, 0xf330b2dc, 0xec52860d, 0xd0e3c177,
231: 0x6c16b32b, 0x99b970a9, 0xfa489411, 0x2264e947, 0xc48cfca8,
232: 0x1a3ff0a0, 0xd82c7d56, 0xef903322, 0xc74e4987, 0xc1d138d9,
233: 0xfea2ca8c, 0x360bd498, 0xcf81f5a6, 0x28de7aa5, 0x268eb7da,
234: 0xa4bfad3f, 0xe49d3a2c, 0x0d927850, 0x9bcc5f6a, 0x62467e54,
235: 0xc2138df6, 0xe8b8d890, 0x5ef7392e, 0xf5afc382, 0xbe805d9f,
236: 0x7c93d069, 0xa92dd56f, 0xb31225cf, 0x3b99acc8, 0xa77d1810,
237: 0x6e639ce8, 0x7bbb3bdb, 0x097826cd, 0xf418596e, 0x01b79aec,
238: 0xa89a4f83, 0x656e95e6, 0x7ee6ffaa, 0x08cfbc21, 0xe6e815ef,
239: 0xd99be7ba, 0xce366f4a, 0xd4099fea, 0xd67cb029, 0xafb2a431,
240: 0x31233f2a, 0x3094a5c6, 0xc066a235, 0x37bc4e74, 0xa6ca82fc,
241: 0xb0d090e0, 0x15d8a733, 0x4a9804f1, 0xf7daec41, 0x0e50cd7f,
242: 0x2ff69117, 0x8dd64d76, 0x4db0ef43, 0x544daacc, 0xdf0496e4,
243: 0xe3b5d19e, 0x1b886a4c, 0xb81f2cc1, 0x7f516546, 0x04ea5e9d,
244: 0x5d358c01, 0x737487fa, 0x2e410bfb, 0x5a1d67b3, 0x52d2db92,
245: 0x335610e9, 0x1347d66d, 0x8c61d79a, 0x7a0ca137, 0x8e14f859,
246: 0x893c13eb, 0xee27a9ce, 0x35c961b7, 0xede51ce1, 0x3cb1477a,
247: 0x59dfd29c, 0x3f73f255, 0x79ce1418, 0xbf37c773, 0xeacdf753,
248: 0x5baafd5f, 0x146f3ddf, 0x86db4478, 0x81f3afca, 0x3ec468b9,
249: 0x2c342438, 0x5f40a3c2, 0x72c31d16, 0x0c25e2bc, 0x8b493c28,
250: 0x41950dff, 0x7101a839, 0xdeb30c08, 0x9ce4b4d8, 0x90c15664,
251: 0x6184cb7b, 0x70b632d5, 0x745c6c48, 0x4257b8d0 };
252:
253: private int shift(int r, int shift) {
254: return (r >>> shift) | (r << -shift);
255: }
256:
257: /* multiply four bytes in GF(2^8) by 'x' {02} in parallel */
258:
259: private static final int m1 = 0x80808080;
260: private static final int m2 = 0x7f7f7f7f;
261: private static final int m3 = 0x0000001b;
262:
263: private int FFmulX(int x) {
264: return (((x & m2) << 1) ^ (((x & m1) >>> 7) * m3));
265: }
266:
267: /*
268: The following defines provide alternative definitions of FFmulX that might
269: give improved performance if a fast 32-bit multiply is not available.
270:
271: private int FFmulX(int x) { int u = x & m1; u |= (u >> 1); return ((x & m2) << 1) ^ ((u >>> 3) | (u >>> 6)); }
272: private static final int m4 = 0x1b1b1b1b;
273: private int FFmulX(int x) { int u = x & m1; return ((x & m2) << 1) ^ ((u - (u >>> 7)) & m4); }
274:
275: */
276:
277: private int inv_mcol(int x) {
278: int f2 = FFmulX(x);
279: int f4 = FFmulX(f2);
280: int f8 = FFmulX(f4);
281: int f9 = x ^ f8;
282:
283: return f2 ^ f4 ^ f8 ^ shift(f2 ^ f9, 8) ^ shift(f4 ^ f9, 16)
284: ^ shift(f9, 24);
285: }
286:
287: private int subWord(int x) {
288: return (S[x & 255] & 255 | ((S[(x >> 8) & 255] & 255) << 8)
289: | ((S[(x >> 16) & 255] & 255) << 16) | S[(x >> 24) & 255] << 24);
290: }
291:
292: /**
293: * Calculate the necessary round keys
294: * The number of calculations depends on key size and block size
295: * AES specified a fixed block size of 128 bits and key sizes 128/192/256 bits
296: * This code is written assuming those are the only possible values
297: */
298: private int[][] generateWorkingKey(byte[] key, boolean forEncryption) {
299: int KC = key.length / 4; // key length in words
300: int t;
301:
302: if (((KC != 4) && (KC != 6) && (KC != 8))
303: || ((KC * 4) != key.length)) {
304: throw new IllegalArgumentException(
305: "Key length not 128/192/256 bits.");
306: }
307:
308: ROUNDS = KC + 6; // This is not always true for the generalized Rijndael that allows larger block sizes
309: int[][] W = new int[ROUNDS + 1][4]; // 4 words in a block
310:
311: //
312: // copy the key into the round key array
313: //
314:
315: t = 0;
316: int i = 0;
317: while (i < key.length) {
318: W[t >> 2][t & 3] = (key[i] & 0xff)
319: | ((key[i + 1] & 0xff) << 8)
320: | ((key[i + 2] & 0xff) << 16) | (key[i + 3] << 24);
321: i += 4;
322: t++;
323: }
324:
325: //
326: // while not enough round key material calculated
327: // calculate new values
328: //
329: int k = (ROUNDS + 1) << 2;
330: for (i = KC; (i < k); i++) {
331: int temp = W[(i - 1) >> 2][(i - 1) & 3];
332: if ((i % KC) == 0) {
333: temp = subWord(shift(temp, 8)) ^ rcon[(i / KC) - 1];
334: } else if ((KC > 6) && ((i % KC) == 4)) {
335: temp = subWord(temp);
336: }
337:
338: W[i >> 2][i & 3] = W[(i - KC) >> 2][(i - KC) & 3] ^ temp;
339: }
340:
341: if (!forEncryption) {
342: for (int j = 1; j < ROUNDS; j++) {
343: for (i = 0; i < 4; i++) {
344: W[j][i] = inv_mcol(W[j][i]);
345: }
346: }
347: }
348:
349: return W;
350: }
351:
352: private int ROUNDS;
353: private int[][] WorkingKey = null;
354: private int C0, C1, C2, C3;
355: private boolean forEncryption;
356:
357: private static final int BLOCK_SIZE = 16;
358:
359: /**
360: * default constructor - 128 bit block size.
361: */
362: public AESEngine() {
363: }
364:
365: /**
366: * initialise an AES cipher.
367: *
368: * @param forEncryption whether or not we are for encryption.
369: * @param params the parameters required to set up the cipher.
370: * @exception IllegalArgumentException if the params argument is
371: * inappropriate.
372: */
373: public void init(boolean forEncryption, CipherParameters params) {
374: if (params instanceof KeyParameter) {
375: WorkingKey = generateWorkingKey(((KeyParameter) params)
376: .getKey(), forEncryption);
377: this .forEncryption = forEncryption;
378: return;
379: }
380:
381: throw new IllegalArgumentException(
382: "invalid parameter passed to AES init - "
383: + params.getClass().getName());
384: }
385:
386: public String getAlgorithmName() {
387: return "AES";
388: }
389:
390: public int getBlockSize() {
391: return BLOCK_SIZE;
392: }
393:
394: public int processBlock(byte[] in, int inOff, byte[] out, int outOff) {
395: if (WorkingKey == null) {
396: throw new IllegalStateException(
397: "AES engine not initialised");
398: }
399:
400: if ((inOff + (32 / 2)) > in.length) {
401: throw new DataLengthException("input buffer too short");
402: }
403:
404: if ((outOff + (32 / 2)) > out.length) {
405: throw new DataLengthException("output buffer too short");
406: }
407:
408: if (forEncryption) {
409: unpackBlock(in, inOff);
410: encryptBlock(WorkingKey);
411: packBlock(out, outOff);
412: } else {
413: unpackBlock(in, inOff);
414: decryptBlock(WorkingKey);
415: packBlock(out, outOff);
416: }
417:
418: return BLOCK_SIZE;
419: }
420:
421: public void reset() {
422: }
423:
424: private final void unpackBlock(byte[] bytes, int off) {
425: int index = off;
426:
427: C0 = (bytes[index++] & 0xff);
428: C0 |= (bytes[index++] & 0xff) << 8;
429: C0 |= (bytes[index++] & 0xff) << 16;
430: C0 |= bytes[index++] << 24;
431:
432: C1 = (bytes[index++] & 0xff);
433: C1 |= (bytes[index++] & 0xff) << 8;
434: C1 |= (bytes[index++] & 0xff) << 16;
435: C1 |= bytes[index++] << 24;
436:
437: C2 = (bytes[index++] & 0xff);
438: C2 |= (bytes[index++] & 0xff) << 8;
439: C2 |= (bytes[index++] & 0xff) << 16;
440: C2 |= bytes[index++] << 24;
441:
442: C3 = (bytes[index++] & 0xff);
443: C3 |= (bytes[index++] & 0xff) << 8;
444: C3 |= (bytes[index++] & 0xff) << 16;
445: C3 |= bytes[index++] << 24;
446: }
447:
448: private final void packBlock(byte[] bytes, int off) {
449: int index = off;
450:
451: bytes[index++] = (byte) C0;
452: bytes[index++] = (byte) (C0 >> 8);
453: bytes[index++] = (byte) (C0 >> 16);
454: bytes[index++] = (byte) (C0 >> 24);
455:
456: bytes[index++] = (byte) C1;
457: bytes[index++] = (byte) (C1 >> 8);
458: bytes[index++] = (byte) (C1 >> 16);
459: bytes[index++] = (byte) (C1 >> 24);
460:
461: bytes[index++] = (byte) C2;
462: bytes[index++] = (byte) (C2 >> 8);
463: bytes[index++] = (byte) (C2 >> 16);
464: bytes[index++] = (byte) (C2 >> 24);
465:
466: bytes[index++] = (byte) C3;
467: bytes[index++] = (byte) (C3 >> 8);
468: bytes[index++] = (byte) (C3 >> 16);
469: bytes[index++] = (byte) (C3 >> 24);
470: }
471:
472: private final void encryptBlock(int[][] KW) {
473: int r, r0, r1, r2, r3;
474:
475: C0 ^= KW[0][0];
476: C1 ^= KW[0][1];
477: C2 ^= KW[0][2];
478: C3 ^= KW[0][3];
479:
480: r = 1;
481:
482: while (r < ROUNDS - 1) {
483: r0 = T0[C0 & 255] ^ shift(T0[(C1 >> 8) & 255], 24)
484: ^ shift(T0[(C2 >> 16) & 255], 16)
485: ^ shift(T0[(C3 >> 24) & 255], 8) ^ KW[r][0];
486: r1 = T0[C1 & 255] ^ shift(T0[(C2 >> 8) & 255], 24)
487: ^ shift(T0[(C3 >> 16) & 255], 16)
488: ^ shift(T0[(C0 >> 24) & 255], 8) ^ KW[r][1];
489: r2 = T0[C2 & 255] ^ shift(T0[(C3 >> 8) & 255], 24)
490: ^ shift(T0[(C0 >> 16) & 255], 16)
491: ^ shift(T0[(C1 >> 24) & 255], 8) ^ KW[r][2];
492: r3 = T0[C3 & 255] ^ shift(T0[(C0 >> 8) & 255], 24)
493: ^ shift(T0[(C1 >> 16) & 255], 16)
494: ^ shift(T0[(C2 >> 24) & 255], 8) ^ KW[r++][3];
495: C0 = T0[r0 & 255] ^ shift(T0[(r1 >> 8) & 255], 24)
496: ^ shift(T0[(r2 >> 16) & 255], 16)
497: ^ shift(T0[(r3 >> 24) & 255], 8) ^ KW[r][0];
498: C1 = T0[r1 & 255] ^ shift(T0[(r2 >> 8) & 255], 24)
499: ^ shift(T0[(r3 >> 16) & 255], 16)
500: ^ shift(T0[(r0 >> 24) & 255], 8) ^ KW[r][1];
501: C2 = T0[r2 & 255] ^ shift(T0[(r3 >> 8) & 255], 24)
502: ^ shift(T0[(r0 >> 16) & 255], 16)
503: ^ shift(T0[(r1 >> 24) & 255], 8) ^ KW[r][2];
504: C3 = T0[r3 & 255] ^ shift(T0[(r0 >> 8) & 255], 24)
505: ^ shift(T0[(r1 >> 16) & 255], 16)
506: ^ shift(T0[(r2 >> 24) & 255], 8) ^ KW[r++][3];
507: }
508:
509: r0 = T0[C0 & 255] ^ shift(T0[(C1 >> 8) & 255], 24)
510: ^ shift(T0[(C2 >> 16) & 255], 16)
511: ^ shift(T0[(C3 >> 24) & 255], 8) ^ KW[r][0];
512: r1 = T0[C1 & 255] ^ shift(T0[(C2 >> 8) & 255], 24)
513: ^ shift(T0[(C3 >> 16) & 255], 16)
514: ^ shift(T0[(C0 >> 24) & 255], 8) ^ KW[r][1];
515: r2 = T0[C2 & 255] ^ shift(T0[(C3 >> 8) & 255], 24)
516: ^ shift(T0[(C0 >> 16) & 255], 16)
517: ^ shift(T0[(C1 >> 24) & 255], 8) ^ KW[r][2];
518: r3 = T0[C3 & 255] ^ shift(T0[(C0 >> 8) & 255], 24)
519: ^ shift(T0[(C1 >> 16) & 255], 16)
520: ^ shift(T0[(C2 >> 24) & 255], 8) ^ KW[r++][3];
521:
522: // the final round's table is a simple function of S so we don't use a whole other four tables for it
523:
524: C0 = (S[r0 & 255] & 255) ^ ((S[(r1 >> 8) & 255] & 255) << 8)
525: ^ ((S[(r2 >> 16) & 255] & 255) << 16)
526: ^ (S[(r3 >> 24) & 255] << 24) ^ KW[r][0];
527: C1 = (S[r1 & 255] & 255) ^ ((S[(r2 >> 8) & 255] & 255) << 8)
528: ^ ((S[(r3 >> 16) & 255] & 255) << 16)
529: ^ (S[(r0 >> 24) & 255] << 24) ^ KW[r][1];
530: C2 = (S[r2 & 255] & 255) ^ ((S[(r3 >> 8) & 255] & 255) << 8)
531: ^ ((S[(r0 >> 16) & 255] & 255) << 16)
532: ^ (S[(r1 >> 24) & 255] << 24) ^ KW[r][2];
533: C3 = (S[r3 & 255] & 255) ^ ((S[(r0 >> 8) & 255] & 255) << 8)
534: ^ ((S[(r1 >> 16) & 255] & 255) << 16)
535: ^ (S[(r2 >> 24) & 255] << 24) ^ KW[r][3];
536:
537: }
538:
539: private final void decryptBlock(int[][] KW) {
540: int r, r0, r1, r2, r3;
541:
542: C0 ^= KW[ROUNDS][0];
543: C1 ^= KW[ROUNDS][1];
544: C2 ^= KW[ROUNDS][2];
545: C3 ^= KW[ROUNDS][3];
546:
547: r = ROUNDS - 1;
548:
549: while (r > 1) {
550: r0 = Tinv0[C0 & 255] ^ shift(Tinv0[(C3 >> 8) & 255], 24)
551: ^ shift(Tinv0[(C2 >> 16) & 255], 16)
552: ^ shift(Tinv0[(C1 >> 24) & 255], 8) ^ KW[r][0];
553: r1 = Tinv0[C1 & 255] ^ shift(Tinv0[(C0 >> 8) & 255], 24)
554: ^ shift(Tinv0[(C3 >> 16) & 255], 16)
555: ^ shift(Tinv0[(C2 >> 24) & 255], 8) ^ KW[r][1];
556: r2 = Tinv0[C2 & 255] ^ shift(Tinv0[(C1 >> 8) & 255], 24)
557: ^ shift(Tinv0[(C0 >> 16) & 255], 16)
558: ^ shift(Tinv0[(C3 >> 24) & 255], 8) ^ KW[r][2];
559: r3 = Tinv0[C3 & 255] ^ shift(Tinv0[(C2 >> 8) & 255], 24)
560: ^ shift(Tinv0[(C1 >> 16) & 255], 16)
561: ^ shift(Tinv0[(C0 >> 24) & 255], 8) ^ KW[r--][3];
562: C0 = Tinv0[r0 & 255] ^ shift(Tinv0[(r3 >> 8) & 255], 24)
563: ^ shift(Tinv0[(r2 >> 16) & 255], 16)
564: ^ shift(Tinv0[(r1 >> 24) & 255], 8) ^ KW[r][0];
565: C1 = Tinv0[r1 & 255] ^ shift(Tinv0[(r0 >> 8) & 255], 24)
566: ^ shift(Tinv0[(r3 >> 16) & 255], 16)
567: ^ shift(Tinv0[(r2 >> 24) & 255], 8) ^ KW[r][1];
568: C2 = Tinv0[r2 & 255] ^ shift(Tinv0[(r1 >> 8) & 255], 24)
569: ^ shift(Tinv0[(r0 >> 16) & 255], 16)
570: ^ shift(Tinv0[(r3 >> 24) & 255], 8) ^ KW[r][2];
571: C3 = Tinv0[r3 & 255] ^ shift(Tinv0[(r2 >> 8) & 255], 24)
572: ^ shift(Tinv0[(r1 >> 16) & 255], 16)
573: ^ shift(Tinv0[(r0 >> 24) & 255], 8) ^ KW[r--][3];
574: }
575:
576: r0 = Tinv0[C0 & 255] ^ shift(Tinv0[(C3 >> 8) & 255], 24)
577: ^ shift(Tinv0[(C2 >> 16) & 255], 16)
578: ^ shift(Tinv0[(C1 >> 24) & 255], 8) ^ KW[r][0];
579: r1 = Tinv0[C1 & 255] ^ shift(Tinv0[(C0 >> 8) & 255], 24)
580: ^ shift(Tinv0[(C3 >> 16) & 255], 16)
581: ^ shift(Tinv0[(C2 >> 24) & 255], 8) ^ KW[r][1];
582: r2 = Tinv0[C2 & 255] ^ shift(Tinv0[(C1 >> 8) & 255], 24)
583: ^ shift(Tinv0[(C0 >> 16) & 255], 16)
584: ^ shift(Tinv0[(C3 >> 24) & 255], 8) ^ KW[r][2];
585: r3 = Tinv0[C3 & 255] ^ shift(Tinv0[(C2 >> 8) & 255], 24)
586: ^ shift(Tinv0[(C1 >> 16) & 255], 16)
587: ^ shift(Tinv0[(C0 >> 24) & 255], 8) ^ KW[r][3];
588:
589: // the final round's table is a simple function of Si so we don't use a whole other four tables for it
590:
591: C0 = (Si[r0 & 255] & 255) ^ ((Si[(r3 >> 8) & 255] & 255) << 8)
592: ^ ((Si[(r2 >> 16) & 255] & 255) << 16)
593: ^ (Si[(r1 >> 24) & 255] << 24) ^ KW[0][0];
594: C1 = (Si[r1 & 255] & 255) ^ ((Si[(r0 >> 8) & 255] & 255) << 8)
595: ^ ((Si[(r3 >> 16) & 255] & 255) << 16)
596: ^ (Si[(r2 >> 24) & 255] << 24) ^ KW[0][1];
597: C2 = (Si[r2 & 255] & 255) ^ ((Si[(r1 >> 8) & 255] & 255) << 8)
598: ^ ((Si[(r0 >> 16) & 255] & 255) << 16)
599: ^ (Si[(r3 >> 24) & 255] << 24) ^ KW[0][2];
600: C3 = (Si[r3 & 255] & 255) ^ ((Si[(r2 >> 8) & 255] & 255) << 8)
601: ^ ((Si[(r1 >> 16) & 255] & 255) << 16)
602: ^ (Si[(r0 >> 24) & 255] << 24) ^ KW[0][3];
603: }
604: }
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