using System; using System.IO; using System.Security.Cryptography; namespace TLSharp.Core.MTProto.Crypto { public class AESKeyData { private readonly byte[] key; private readonly byte[] iv; public AESKeyData(byte[] key, byte[] iv) { this.key = key; this.iv = iv; } public byte[] Key { get { return key; } } public byte[] Iv { get { return iv; } } } public class AES { public static byte[] DecryptWithNonces(byte[] data, byte[] serverNonce, byte[] newNonce) { using(SHA1 hash = new SHA1Managed()) { var nonces = new byte[48]; newNonce.CopyTo(nonces, 0); serverNonce.CopyTo(nonces, 32); byte[] hash1 = hash.ComputeHash(nonces); serverNonce.CopyTo(nonces, 0); newNonce.CopyTo(nonces, 16); byte[] hash2 = hash.ComputeHash(nonces); nonces = new byte[64]; newNonce.CopyTo(nonces, 0); newNonce.CopyTo(nonces, 32); byte[] hash3 = hash.ComputeHash(nonces); using(var keyBuffer = new MemoryStream(32)) using(var ivBuffer = new MemoryStream(32)) { keyBuffer.Write(hash1, 0, hash1.Length); keyBuffer.Write(hash2, 0, 12); ivBuffer.Write(hash2, 12, 8); ivBuffer.Write(hash3, 0, hash3.Length); ivBuffer.Write(newNonce, 0, 4); return DecryptIGE(data, keyBuffer.ToArray(), ivBuffer.ToArray()); } } } public static AESKeyData GenerateKeyDataFromNonces(byte[] serverNonce, byte[] newNonce) { using (SHA1 hash = new SHA1Managed()) { var nonces = new byte[48]; newNonce.CopyTo(nonces, 0); serverNonce.CopyTo(nonces, 32); byte[] hash1 = hash.ComputeHash(nonces); serverNonce.CopyTo(nonces, 0); newNonce.CopyTo(nonces, 16); byte[] hash2 = hash.ComputeHash(nonces); nonces = new byte[64]; newNonce.CopyTo(nonces, 0); newNonce.CopyTo(nonces, 32); byte[] hash3 = hash.ComputeHash(nonces); using (var keyBuffer = new MemoryStream(32)) using (var ivBuffer = new MemoryStream(32)) { keyBuffer.Write(hash1, 0, hash1.Length); keyBuffer.Write(hash2, 0, 12); ivBuffer.Write(hash2, 12, 8); ivBuffer.Write(hash3, 0, hash3.Length); ivBuffer.Write(newNonce, 0, 4); return new AESKeyData(keyBuffer.ToArray(), ivBuffer.ToArray()); } } } public static byte[] DecryptAES(AESKeyData key, byte[] ciphertext) { return DecryptIGE(ciphertext, key.Key, key.Iv); } public static byte[] EncryptAES(AESKeyData key, byte[] plaintext) { return EncryptIGE(plaintext, key.Key, key.Iv); } public static byte[] DecryptIGE(byte[] ciphertext, byte[] key, byte[] iv) { var iv1 = new byte[iv.Length/2]; var iv2 = new byte[iv.Length/2]; Array.Copy(iv, 0, iv1, 0, iv1.Length); Array.Copy(iv, iv1.Length, iv2, 0, iv2.Length); AesEngine aes = new AesEngine(); aes.Init(false, key); byte[] plaintext = new byte[ciphertext.Length]; int blocksCount = ciphertext.Length/16; byte[] ciphertextBlock = new byte[16]; byte[] plaintextBlock = new byte[16]; for(int blockIndex = 0; blockIndex < blocksCount; blockIndex++) { for(int i = 0; i < 16; i++) { ciphertextBlock[i] = (byte) (ciphertext[blockIndex*16 + i] ^ iv2[i]); } aes.ProcessBlock(ciphertextBlock, 0, plaintextBlock, 0); for(int i = 0; i < 16; i++) { plaintextBlock[i] ^= iv1[i]; } Array.Copy(ciphertext, blockIndex * 16, iv1, 0, 16); Array.Copy(plaintextBlock, 0, iv2, 0, 16); Array.Copy(plaintextBlock, 0, plaintext, blockIndex * 16, 16); } return plaintext; } public static byte[] EncryptIGE(byte[] originPlaintext, byte[] key, byte[] iv) { byte[] plaintext; using (MemoryStream plaintextBuffer = new MemoryStream(originPlaintext.Length + 40)) { //using(SHA1 hash = new SHA1Managed()) { //byte[] hashsum = hash.ComputeHash(originPlaintext); //plaintextBuffer.Write(hashsum, 0, hashsum.Length); plaintextBuffer.Write(originPlaintext, 0, originPlaintext.Length); while(plaintextBuffer.Position%16 != 0) { plaintextBuffer.WriteByte(0); // TODO: random padding } plaintext = plaintextBuffer.ToArray(); } var iv1 = new byte[iv.Length/2]; var iv2 = new byte[iv.Length/2]; Array.Copy(iv, 0, iv1, 0, iv1.Length); Array.Copy(iv, iv1.Length, iv2, 0, iv2.Length); AesEngine aes = new AesEngine(); aes.Init(true, key); int blocksCount = plaintext.Length/16; byte[] ciphertext = new byte[plaintext.Length]; byte[] ciphertextBlock = new byte[16]; byte[] plaintextBlock = new byte[16]; for(int blockIndex = 0; blockIndex < blocksCount; blockIndex++) { Array.Copy(plaintext, 16*blockIndex, plaintextBlock, 0, 16); //logger.info("plaintext block: {0} xor {1}", BitConverter.ToString(plaintextBlock).Replace("-", ""), BitConverter.ToString(iv1).Replace("-", "")); for(int i = 0; i < 16; i++) { plaintextBlock[i] ^= iv1[i]; } //logger.info("xored plaintext: {0}", BitConverter.ToString(plaintextBlock).Replace("-", "")); aes.ProcessBlock(plaintextBlock, 0, ciphertextBlock, 0); //logger.info("encrypted plaintext: {0} xor {1}", BitConverter.ToString(ciphertextBlock).Replace("-", ""), BitConverter.ToString(iv2).Replace("-", "")); for(int i = 0; i < 16; i++) { ciphertextBlock[i] ^= iv2[i]; } //logger.info("xored ciphertext: {0}", BitConverter.ToString(ciphertextBlock).Replace("-", "")); Array.Copy(ciphertextBlock, 0, iv1, 0, 16); Array.Copy(plaintext, 16*blockIndex, iv2, 0, 16); Array.Copy(ciphertextBlock, 0, ciphertext, blockIndex * 16, 16); } return ciphertext; } public static byte[] XOR(byte[] buffer1, byte[] buffer2) { var result = new byte[buffer1.Length]; for(int i = 0; i < buffer1.Length; i++) result[i] = (byte) (buffer1[i] ^ buffer2[i]); return result; } } // AES engine implementation public class AesEngine { // The S box private const uint m1 = 0x80808080; private const uint m2 = 0x7f7f7f7f; private const uint m3 = 0x0000001b; private const int BLOCK_SIZE = 16; private static readonly byte[] S = { 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 }; // The inverse S-box private static readonly byte[] Si = { 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 }; // vector used in calculating key schedule (powers of x in GF(256)) private static readonly byte[] rcon = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91 }; // precomputation tables of calculations for rounds private static readonly uint[] T0 = { 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 }; private static readonly uint[] Tinv0 = { 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 }; private uint C0, C1, C2, C3; private int ROUNDS; private uint[,] WorkingKey; private bool forEncryption; public string AlgorithmName { get { return "AES"; } } public bool IsPartialBlockOkay { get { return false; } } private uint Shift( uint r, int shift) { return (r >> shift) | (r << (32 - shift)); } private uint FFmulX( uint x) { return ((x & m2) << 1) ^ (((x & m1) >> 7)*m3); } /* The following defines provide alternative definitions of FFmulX that might give improved performance if a fast 32-bit multiply is not available. private int FFmulX(int x) { int u = x & m1; u |= (u >> 1); return ((x & m2) << 1) ^ ((u >>> 3) | (u >>> 6)); } private static final int m4 = 0x1b1b1b1b; private int FFmulX(int x) { int u = x & m1; return ((x & m2) << 1) ^ ((u - (u >>> 7)) & m4); } */ private uint Inv_Mcol( uint x) { uint f2 = FFmulX(x); uint f4 = FFmulX(f2); uint f8 = FFmulX(f4); uint f9 = x ^ f8; return f2 ^ f4 ^ f8 ^ Shift(f2 ^ f9, 8) ^ Shift(f4 ^ f9, 16) ^ Shift(f9, 24); } private uint SubWord( uint x) { return S[x & 255] | (((uint) S[(x >> 8) & 255]) << 8) | (((uint) S[(x >> 16) & 255]) << 16) | (((uint) S[(x >> 24) & 255]) << 24); } /** * Calculate the necessary round keys * The number of calculations depends on key size and block size * AES specified a fixed block size of 128 bits and key sizes 128/192/256 bits * This code is written assuming those are the only possible values */ private uint[,] GenerateWorkingKey( byte[] key, bool forEncryption) { int KC = key.Length/4; // key length in words int t; if((KC != 4) && (KC != 6) && (KC != 8)) throw new ArgumentException("Key length not 128/192/256 bits."); ROUNDS = KC + 6; // This is not always true for the generalized Rijndael that allows larger block sizes var W = new uint[ROUNDS + 1, 4]; // 4 words in a block // // copy the key into the round key array // t = 0; for(int i = 0; i < key.Length; t++) { W[t >> 2, t & 3] = Pack.LE_To_UInt32(key, i); i += 4; } // // while not enough round key material calculated // calculate new values // int k = (ROUNDS + 1) << 2; for(int i = KC; (i < k); i++) { uint temp = W[(i - 1) >> 2, (i - 1) & 3]; if((i%KC) == 0) { temp = SubWord(Shift(temp, 8)) ^ rcon[(i/KC) - 1]; } else if((KC > 6) && ((i%KC) == 4)) { temp = SubWord(temp); } W[i >> 2, i & 3] = W[(i - KC) >> 2, (i - KC) & 3] ^ temp; } if(!forEncryption) { for(int j = 1; j < ROUNDS; j++) { for(int i = 0; i < 4; i++) { W[j, i] = Inv_Mcol(W[j, i]); } } } return W; } public void Init(bool forEncryption, byte[] key) { WorkingKey = GenerateWorkingKey(key, forEncryption); this.forEncryption = forEncryption; } public int GetBlockSize() { return BLOCK_SIZE; } public int ProcessBlock(byte[] input, int inOff, byte[] output, int outOff) { if(WorkingKey == null) { throw new InvalidOperationException("AES engine not initialised"); } if((inOff + (32/2)) > input.Length) { throw new InvalidOperationException("input buffer too short"); } if((outOff + (32/2)) > output.Length) { throw new InvalidOperationException("output buffer too short"); } UnPackBlock(input, inOff); if(forEncryption) { EncryptBlock(WorkingKey); } else { DecryptBlock(WorkingKey); } PackBlock(output, outOff); return BLOCK_SIZE; } public void Reset() { } private void UnPackBlock( byte[] bytes, int off) { C0 = Pack.LE_To_UInt32(bytes, off); C1 = Pack.LE_To_UInt32(bytes, off + 4); C2 = Pack.LE_To_UInt32(bytes, off + 8); C3 = Pack.LE_To_UInt32(bytes, off + 12); } private void PackBlock( byte[] bytes, int off) { Pack.UInt32_To_LE(C0, bytes, off); Pack.UInt32_To_LE(C1, bytes, off + 4); Pack.UInt32_To_LE(C2, bytes, off + 8); Pack.UInt32_To_LE(C3, bytes, off + 12); } private void EncryptBlock( uint[,] KW) { uint r, r0, r1, r2, r3; C0 ^= KW[0, 0]; C1 ^= KW[0, 1]; C2 ^= KW[0, 2]; C3 ^= KW[0, 3]; for(r = 1; r < ROUNDS - 1;) { r0 = T0[C0 & 255] ^ Shift(T0[(C1 >> 8) & 255], 24) ^ Shift(T0[(C2 >> 16) & 255], 16) ^ Shift(T0[(C3 >> 24) & 255], 8) ^ KW[r, 0]; r1 = T0[C1 & 255] ^ Shift(T0[(C2 >> 8) & 255], 24) ^ Shift(T0[(C3 >> 16) & 255], 16) ^ Shift(T0[(C0 >> 24) & 255], 8) ^ KW[r, 1]; r2 = T0[C2 & 255] ^ Shift(T0[(C3 >> 8) & 255], 24) ^ Shift(T0[(C0 >> 16) & 255], 16) ^ Shift(T0[(C1 >> 24) & 255], 8) ^ KW[r, 2]; r3 = T0[C3 & 255] ^ Shift(T0[(C0 >> 8) & 255], 24) ^ Shift(T0[(C1 >> 16) & 255], 16) ^ Shift(T0[(C2 >> 24) & 255], 8) ^ KW[r++, 3]; C0 = T0[r0 & 255] ^ Shift(T0[(r1 >> 8) & 255], 24) ^ Shift(T0[(r2 >> 16) & 255], 16) ^ Shift(T0[(r3 >> 24) & 255], 8) ^ KW[r, 0]; C1 = T0[r1 & 255] ^ Shift(T0[(r2 >> 8) & 255], 24) ^ Shift(T0[(r3 >> 16) & 255], 16) ^ Shift(T0[(r0 >> 24) & 255], 8) ^ KW[r, 1]; C2 = T0[r2 & 255] ^ Shift(T0[(r3 >> 8) & 255], 24) ^ Shift(T0[(r0 >> 16) & 255], 16) ^ Shift(T0[(r1 >> 24) & 255], 8) ^ KW[r, 2]; C3 = T0[r3 & 255] ^ Shift(T0[(r0 >> 8) & 255], 24) ^ Shift(T0[(r1 >> 16) & 255], 16) ^ Shift(T0[(r2 >> 24) & 255], 8) ^ KW[r++, 3]; } r0 = T0[C0 & 255] ^ Shift(T0[(C1 >> 8) & 255], 24) ^ Shift(T0[(C2 >> 16) & 255], 16) ^ Shift(T0[(C3 >> 24) & 255], 8) ^ KW[r, 0]; r1 = T0[C1 & 255] ^ Shift(T0[(C2 >> 8) & 255], 24) ^ Shift(T0[(C3 >> 16) & 255], 16) ^ Shift(T0[(C0 >> 24) & 255], 8) ^ KW[r, 1]; r2 = T0[C2 & 255] ^ Shift(T0[(C3 >> 8) & 255], 24) ^ Shift(T0[(C0 >> 16) & 255], 16) ^ Shift(T0[(C1 >> 24) & 255], 8) ^ KW[r, 2]; r3 = T0[C3 & 255] ^ Shift(T0[(C0 >> 8) & 255], 24) ^ Shift(T0[(C1 >> 16) & 255], 16) ^ Shift(T0[(C2 >> 24) & 255], 8) ^ KW[r++, 3]; // the final round's table is a simple function of S so we don't use a whole other four tables for it C0 = S[r0 & 255] ^ (((uint) S[(r1 >> 8) & 255]) << 8) ^ (((uint) S[(r2 >> 16) & 255]) << 16) ^ (((uint) S[(r3 >> 24) & 255]) << 24) ^ KW[r, 0]; C1 = S[r1 & 255] ^ (((uint) S[(r2 >> 8) & 255]) << 8) ^ (((uint) S[(r3 >> 16) & 255]) << 16) ^ (((uint) S[(r0 >> 24) & 255]) << 24) ^ KW[r, 1]; C2 = S[r2 & 255] ^ (((uint) S[(r3 >> 8) & 255]) << 8) ^ (((uint) S[(r0 >> 16) & 255]) << 16) ^ (((uint) S[(r1 >> 24) & 255]) << 24) ^ KW[r, 2]; C3 = S[r3 & 255] ^ (((uint) S[(r0 >> 8) & 255]) << 8) ^ (((uint) S[(r1 >> 16) & 255]) << 16) ^ (((uint) S[(r2 >> 24) & 255]) << 24) ^ KW[r, 3]; } private void DecryptBlock( uint[,] KW) { int r; uint r0, r1, r2, r3; C0 ^= KW[ROUNDS, 0]; C1 ^= KW[ROUNDS, 1]; C2 ^= KW[ROUNDS, 2]; C3 ^= KW[ROUNDS, 3]; for(r = ROUNDS - 1; r > 1;) { r0 = Tinv0[C0 & 255] ^ Shift(Tinv0[(C3 >> 8) & 255], 24) ^ Shift(Tinv0[(C2 >> 16) & 255], 16) ^ Shift(Tinv0[(C1 >> 24) & 255], 8) ^ KW[r, 0]; r1 = Tinv0[C1 & 255] ^ Shift(Tinv0[(C0 >> 8) & 255], 24) ^ Shift(Tinv0[(C3 >> 16) & 255], 16) ^ Shift(Tinv0[(C2 >> 24) & 255], 8) ^ KW[r, 1]; r2 = Tinv0[C2 & 255] ^ Shift(Tinv0[(C1 >> 8) & 255], 24) ^ Shift(Tinv0[(C0 >> 16) & 255], 16) ^ Shift(Tinv0[(C3 >> 24) & 255], 8) ^ KW[r, 2]; r3 = Tinv0[C3 & 255] ^ Shift(Tinv0[(C2 >> 8) & 255], 24) ^ Shift(Tinv0[(C1 >> 16) & 255], 16) ^ Shift(Tinv0[(C0 >> 24) & 255], 8) ^ KW[r--, 3]; C0 = Tinv0[r0 & 255] ^ Shift(Tinv0[(r3 >> 8) & 255], 24) ^ Shift(Tinv0[(r2 >> 16) & 255], 16) ^ Shift(Tinv0[(r1 >> 24) & 255], 8) ^ KW[r, 0]; C1 = Tinv0[r1 & 255] ^ Shift(Tinv0[(r0 >> 8) & 255], 24) ^ Shift(Tinv0[(r3 >> 16) & 255], 16) ^ Shift(Tinv0[(r2 >> 24) & 255], 8) ^ KW[r, 1]; C2 = Tinv0[r2 & 255] ^ Shift(Tinv0[(r1 >> 8) & 255], 24) ^ Shift(Tinv0[(r0 >> 16) & 255], 16) ^ Shift(Tinv0[(r3 >> 24) & 255], 8) ^ KW[r, 2]; C3 = Tinv0[r3 & 255] ^ Shift(Tinv0[(r2 >> 8) & 255], 24) ^ Shift(Tinv0[(r1 >> 16) & 255], 16) ^ Shift(Tinv0[(r0 >> 24) & 255], 8) ^ KW[r--, 3]; } r0 = Tinv0[C0 & 255] ^ Shift(Tinv0[(C3 >> 8) & 255], 24) ^ Shift(Tinv0[(C2 >> 16) & 255], 16) ^ Shift(Tinv0[(C1 >> 24) & 255], 8) ^ KW[r, 0]; r1 = Tinv0[C1 & 255] ^ Shift(Tinv0[(C0 >> 8) & 255], 24) ^ Shift(Tinv0[(C3 >> 16) & 255], 16) ^ Shift(Tinv0[(C2 >> 24) & 255], 8) ^ KW[r, 1]; r2 = Tinv0[C2 & 255] ^ Shift(Tinv0[(C1 >> 8) & 255], 24) ^ Shift(Tinv0[(C0 >> 16) & 255], 16) ^ Shift(Tinv0[(C3 >> 24) & 255], 8) ^ KW[r, 2]; r3 = Tinv0[C3 & 255] ^ Shift(Tinv0[(C2 >> 8) & 255], 24) ^ Shift(Tinv0[(C1 >> 16) & 255], 16) ^ Shift(Tinv0[(C0 >> 24) & 255], 8) ^ KW[r, 3]; // the final round's table is a simple function of Si so we don't use a whole other four tables for it C0 = Si[r0 & 255] ^ (((uint) Si[(r3 >> 8) & 255]) << 8) ^ (((uint) Si[(r2 >> 16) & 255]) << 16) ^ (((uint) Si[(r1 >> 24) & 255]) << 24) ^ KW[0, 0]; C1 = Si[r1 & 255] ^ (((uint) Si[(r0 >> 8) & 255]) << 8) ^ (((uint) Si[(r3 >> 16) & 255]) << 16) ^ (((uint) Si[(r2 >> 24) & 255]) << 24) ^ KW[0, 1]; C2 = Si[r2 & 255] ^ (((uint) Si[(r1 >> 8) & 255]) << 8) ^ (((uint) Si[(r0 >> 16) & 255]) << 16) ^ (((uint) Si[(r3 >> 24) & 255]) << 24) ^ KW[0, 2]; C3 = Si[r3 & 255] ^ (((uint) Si[(r2 >> 8) & 255]) << 8) ^ (((uint) Si[(r1 >> 16) & 255]) << 16) ^ (((uint) Si[(r0 >> 24) & 255]) << 24) ^ KW[0, 3]; } } internal sealed class Pack { private Pack() { } internal static void UInt32_To_BE(uint n, byte[] bs) { bs[0] = (byte) (n >> 24); bs[1] = (byte) (n >> 16); bs[2] = (byte) (n >> 8); bs[3] = (byte) (n); } internal static void UInt32_To_BE(uint n, byte[] bs, int off) { bs[off] = (byte) (n >> 24); bs[++off] = (byte) (n >> 16); bs[++off] = (byte) (n >> 8); bs[++off] = (byte) (n); } internal static uint BE_To_UInt32(byte[] bs) { uint n = (uint) bs[0] << 24; n |= (uint) bs[1] << 16; n |= (uint) bs[2] << 8; n |= bs[3]; return n; } internal static uint BE_To_UInt32(byte[] bs, int off) { uint n = (uint) bs[off] << 24; n |= (uint) bs[++off] << 16; n |= (uint) bs[++off] << 8; n |= bs[++off]; return n; } internal static ulong BE_To_UInt64(byte[] bs) { uint hi = BE_To_UInt32(bs); uint lo = BE_To_UInt32(bs, 4); return ((ulong) hi << 32) | lo; } internal static ulong BE_To_UInt64(byte[] bs, int off) { uint hi = BE_To_UInt32(bs, off); uint lo = BE_To_UInt32(bs, off + 4); return ((ulong) hi << 32) | lo; } internal static void UInt64_To_BE(ulong n, byte[] bs) { UInt32_To_BE((uint) (n >> 32), bs); UInt32_To_BE((uint) (n), bs, 4); } internal static void UInt64_To_BE(ulong n, byte[] bs, int off) { UInt32_To_BE((uint) (n >> 32), bs, off); UInt32_To_BE((uint) (n), bs, off + 4); } internal static void UInt32_To_LE(uint n, byte[] bs) { bs[0] = (byte) (n); bs[1] = (byte) (n >> 8); bs[2] = (byte) (n >> 16); bs[3] = (byte) (n >> 24); } internal static void UInt32_To_LE(uint n, byte[] bs, int off) { bs[off] = (byte) (n); bs[++off] = (byte) (n >> 8); bs[++off] = (byte) (n >> 16); bs[++off] = (byte) (n >> 24); } internal static uint LE_To_UInt32(byte[] bs) { uint n = bs[0]; n |= (uint) bs[1] << 8; n |= (uint) bs[2] << 16; n |= (uint) bs[3] << 24; return n; } internal static uint LE_To_UInt32(byte[] bs, int off) { uint n = bs[off]; n |= (uint) bs[++off] << 8; n |= (uint) bs[++off] << 16; n |= (uint) bs[++off] << 24; return n; } internal static ulong LE_To_UInt64(byte[] bs) { uint lo = LE_To_UInt32(bs); uint hi = LE_To_UInt32(bs, 4); return ((ulong) hi << 32) | lo; } internal static ulong LE_To_UInt64(byte[] bs, int off) { uint lo = LE_To_UInt32(bs, off); uint hi = LE_To_UInt32(bs, off + 4); return ((ulong) hi << 32) | lo; } internal static void UInt64_To_LE(ulong n, byte[] bs) { UInt32_To_LE((uint) (n), bs); UInt32_To_LE((uint) (n >> 32), bs, 4); } internal static void UInt64_To_LE(ulong n, byte[] bs, int off) { UInt32_To_LE((uint) (n), bs, off); UInt32_To_LE((uint) (n >> 32), bs, off + 4); } } }